WO2021085283A1 - Polyamideimide resin - Google Patents

Polyamideimide resin Download PDF

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Publication number
WO2021085283A1
WO2021085283A1 PCT/JP2020/039650 JP2020039650W WO2021085283A1 WO 2021085283 A1 WO2021085283 A1 WO 2021085283A1 JP 2020039650 W JP2020039650 W JP 2020039650W WO 2021085283 A1 WO2021085283 A1 WO 2021085283A1
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Prior art keywords
group
formula
halogen atom
optical film
polyamide
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PCT/JP2020/039650
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French (fr)
Japanese (ja)
Inventor
皓史 宮本
貴将 江川
Original Assignee
住友化学株式会社
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Priority claimed from JP2020171456A external-priority patent/JP2021075700A/en
Application filed by 住友化学株式会社 filed Critical 住友化学株式会社
Priority to KR1020227018173A priority Critical patent/KR20220095208A/en
Priority to CN202080074802.0A priority patent/CN114599708A/en
Publication of WO2021085283A1 publication Critical patent/WO2021085283A1/en

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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
    • C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
    • C08G73/10—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
    • C08G73/14—Polyamide-imides
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
    • C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
    • C08G73/10—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
    • C08G73/16—Polyester-imides
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
    • G09F9/00—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements

Definitions

  • the present invention relates to a polyamide-imide resin and an optical film containing the polyamide-imide resin.
  • Display devices such as liquid crystal display devices and organic EL display devices are widely used in various applications such as mobile phones and smart watches.
  • Glass has been used as the front plate of such a display device, but it is difficult to use it as a front plate material of a flexible display device because the glass is very rigid and easily broken. Therefore, the use of polymer materials as an alternative material to glass is being studied. Since the front plate made of a polymer material easily exhibits flexible properties, it can be expected to be used for various purposes.
  • Various types of flexible resins can be mentioned, and one of them is a polyimide resin.
  • Patent Document 1 and Patent Document 2 describe an optical film formed of a polyimide resin or a polyamide-imide resin.
  • Optical films used as materials for flexible display devices are required to have features such as folding resistance.
  • the present inventors have conducted studies in order to enhance these required performances of the optical film, and have found that an optical film having excellent folding resistance and the like can be obtained by increasing the proof stress of the optical film.
  • an object of the present invention is to provide a polyamide-imide resin capable of providing an optical film having a high yield strength, and the optical film.
  • Equation (1) and Equation (2) [1] Equation (1) and Equation (2):
  • R 1 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group which may have a halogen atom or a halogen atom independently of each other
  • R 2 to R 5 are Independently of each other, they represent a monovalent hydrocarbon group which may have a hydrogen atom or a halogen atom
  • m represents an integer of 0 to 3 independently of each other
  • n represents an integer of 1 to 4.
  • * represents a bonding hand, provided that at least one benzene ring having R 2 ⁇ R 5, at least one 1 may have a halogen atom monovalent hydrocarbon group R 2 ⁇ R 5
  • A is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-,-.
  • R A1 and R A2 are, independently of one another, may have a hydrogen atom, or a halogen atom
  • R 6 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, which may have a halogen atom or a halogen atom independently of each other, and s represents 0 to independently of each other.
  • * represents a bond
  • B is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-,-. It represents COO-, -PO-, -PO 2- , -N ( RB1 )-or-Si ( RB2 ) 2- , and RB1 and RB2 have hydrogen atoms or halogen atoms independently of each other.
  • R 7 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group which may have a halogen atom and a halogen atom independently of each other
  • t represents an alkyl group which may have a halogen atom and a halogen atom.
  • * represents a bond
  • W independently of one another, a single bond, -O-, diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2 -, - S - , - It represents CO-, -PO-, -PO 2- , -N ( RC1 )-or-Si ( RC2 ) 2- , and RC1 and RC2 have hydrogen atom or halogen atom independently of each other.
  • R 8 represents an alkyl group which may have a halogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, and p is independent of each other.
  • the polyamide-imide resin according to any one of [1] to [4] above which comprises the structure represented by.
  • [6] The polyamide-imide resin according to any one of [1] to [5] above, wherein the weight average molecular weight is 100,000 or more.
  • [8] The optical film according to the above [7], which has a yellowness of less than 3.0.
  • the optical film according to any one of [7] to [9] above which has an elastic modulus of 5.0 GPa or more.
  • the optical film according to any one of [7] to [10] above which is a film for a front plate of a flexible display device.
  • the flexible display device according to the above [12] further comprising a touch sensor.
  • the polyamide-imide resin of the present invention has the formulas (1) and (2):
  • Y represents a tetravalent organic group independently of each other, preferably a tetravalent organic group having 4 to 80 carbon atoms, and more preferably a tetravalent organic group having a cyclic structure and having 4 to 60 carbon atoms.
  • the cyclic structure include an alicyclic ring, an aromatic ring, and a heterocyclic structure.
  • the organic group is an organic group which may have a substituent, and the substituent may preferably have a halogen atom or a halogen atom, and is a monovalent hydrocarbon group (for example, an alkyl group or an aryl group). Etc.), alkoxy group or aryloxy group.
  • the polyamide-imide resin according to the embodiment of the present invention may contain a plurality of types of Y, and the plurality of types of Y may be the same as or different from each other.
  • polyamide-imide resin of the present invention has a formula (3): as Y in the formula (1).
  • R 1 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group which may have a halogen atom or a halogen atom independently of each other
  • R 2 to R 5 are Independently of each other, they represent a monovalent hydrocarbon group which may have a hydrogen atom or a halogen atom
  • m represents an integer of 0 to 3 independently of each other
  • n represents an integer of 1 to 4.
  • * represents a bonding hand, provided that at least one benzene ring having R 2 ⁇ R 5, at least one 1 may have a halogen atom monovalent hydrocarbon group R 2 ⁇ R 5] Including at least the structure represented by.
  • the present inventors consider that Y in the formula (1) contains at least the structure represented by the formula (3). It has been found that the proof stress of the optical film containing the polyamide-imide resin is improved. Although it is not clear why the polyamide-imide resin is likely to increase the proof stress of the optical film by including the structure represented by the formula (3) as Y in the formula (1), it is represented by the formula (3). Since the structure is rigid but has side chains, it is a structure that hinders intermolecular packing. By including such a structure, the polyamide-imide resin has a high elastic modulus and high toughness, and the stress until yielding is further increased. It is thought that this is to improve. Further, since the polyamide-imide resin of the present invention contains such a structure, it has excellent optical properties, and can achieve both high yield strength and excellent optical properties.
  • R 1 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, which may have a halogen atom or a halogen atom independently of each other.
  • the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
  • the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, 2-methyl-butyl group and 3-methylbutyl group.
  • Groups, 2-ethyl-propyl groups, n-hexyl groups and the like can be mentioned.
  • the alkoxy group include a methoxy group, an ethoxy group, a propyloxy group, an isopropyloxy group, a butoxy group, an isobutoxy group, a tert-butoxy group, a pentyloxy group, a hexyloxy group, a cyclohexyloxy group and the like.
  • Examples of the aryl group include a phenyl group, a tolyl group, a xsilyl group, a naphthyl group, a biphenyl group and the like.
  • aryloxy group examples include a phenoxy group, a naphthyloxy group, a biphenyloxy group and the like.
  • R 1 is independent of each other, preferably having a halogen atom or a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, and the like. Alternatively, it represents an aryloxy group having 6 to 12 carbon atoms.
  • m is independent of each other from the viewpoint of easily improving the elasticity and transparency of the optical film containing the polyamide-imide resin (hereinafter, may be simply referred to as the optical film) and improving the resistance.
  • it represents an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 0.
  • R 2 , R 3 , R 4 and R 5 represent monovalent hydrocarbon groups that may have hydrogen or halogen atoms independently of each other.
  • the monovalent hydrocarbon group include an aromatic hydrocarbon group, an alicyclic hydrocarbon group, and an aliphatic hydrocarbon group.
  • the aromatic hydrocarbon group include an aryl group such as a phenyl group, a tolyl group, a xsilyl group, a naphthyl group and a biphenyl group.
  • the alicyclic hydrocarbon group include a cycloalkyl group such as a cyclopentyl group and a cyclohexyl group.
  • Examples of the aliphatic hydrocarbon group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group and a 2-methyl-butyl group.
  • Examples thereof include alkyl groups such as 3-methylbutyl group, 2-ethyl-propyl group, n-hexyl, n-heptyl group, n-octyl group, tert-octyl group, n-nonyl group and n-decyl group.
  • Examples of the halogen atom include those described above.
  • R 2 - R 5 are, independently of one another, preferably a hydrogen atom, or a halogen atom may have an aryl group having 6 to 12 carbon atoms, a cycloalkyl group having 4 to 8 carbon atoms, or C 1 -C Represents an alkyl group of 6.
  • R 2 ⁇ R 5 independently of one another, preferably a hydrogen atom, Alternatively, it may have an alkyl group which may have a halogen atom, more preferably a hydrogen atom, or 1 to 6 alkyl groups which may have a halogen atom, and more preferably a hydrogen atom or a halogen atom1. Represents ⁇ 3 alkyl groups.
  • At least one benzene ring having R 2 ⁇ R 5, at least one 1 may have a halogen atom monovalent hydrocarbon group R 2 ⁇ R 5.
  • R 2 ⁇ R 5 in all of the benzene ring having R 2 ⁇ R 5 in formula (3), of the R 2 ⁇ R 5, when the monovalent hydrocarbon group which may have a halogen atom is fewer than one optical It is difficult to sufficiently improve the yield strength of the film, and the optical characteristics are likely to deteriorate.
  • preferably 2 of R 2 to R 5 is used in at least one benzene ring having R 2 to R 5.
  • ⁇ 4, more preferably 3 or 4, still more preferably 3 are monovalent hydrocarbon groups which may have halogen atoms.
  • n 2 or more, at least two benzene rings having R 2 ⁇ R 5, more preferably at least one of R 2 ⁇ R 5 is a monovalent hydrocarbon group which may have a halogen atom, in all the benzene ring having R 2 ⁇ R 5, at least R 2 ⁇ R 5 It is more preferable that one is a monovalent hydrocarbon group which may have a halogen atom.
  • n represents an integer of 1 to 4, and n is preferably an integer of 1 to 3, more preferably 2 or 3, from the viewpoint of easily improving the strength, elastic modulus and transparency of the optical film. More preferably, it is 2.
  • the structural unit represented by the formula (1) may include one or more types of structures (or groups) represented by the formula (3) as Y.
  • the formula (3) is the formula (3'):
  • the polyamide-imide resin contains a structure represented by the formula (3') as Y in the formula (1). With such a form, it is easy to improve the proof stress, elastic modulus and transparency of the optical film.
  • the proportion of the structural units having a structure in which Y is represented by the formula (3) is the structural unit represented by the formula (1). 30 mol% or more, more preferably 35 mol% or more, still more preferably 40 mol% or more, preferably 100 mol% or less, more preferably 90 mol, based on the total molar amount (100 mol%) of % Or less, more preferably 80 mol% or less, and particularly preferably 70 mol% or less.
  • the proportion of the structural unit in which Y is represented by the formula (3) is at least the above lower limit value, the proof stress and elastic modulus of the optical film can be easily improved.
  • the ratio of the structural unit in which Y is represented by the formula (3) can be measured using, for example, 1 1 H-NMR, or can be calculated from the charging ratio of raw materials.
  • the polyamide-imide resin of the present invention has the formula (20), the formula (21), the formula (22), the formula (23), the formula (24), the formula (25), and the formula (25) as Y in the formula (1). 26), Eq. (27), Eq. (28) and Eq. (29):
  • * represents a bond
  • W 1 is a single bond, —O—, a diphenylmethylene group, and a divalent hydrocarbon group (eg, ⁇ ” which may have a halogen atom.
  • Ar represents an arylene group having 6 to 20 carbon atoms which may have a fluorine atom, and specific examples thereof include a phenylene group.
  • RW1 and RW2 represent alkyl groups which may have a hydrogen atom or a halogen atom independently of each other.
  • the hydrogen atom in the group represented by the formulas (20) to (29) is a group substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; and a tetravalent group having 6 or less carbon atoms. It may be a chain hydrocarbon group.
  • the hydrogen atom on the ring in the formulas (20) to (29) is substituted with an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms. May be good.
  • alkyl group having 1 to 6 carbon atoms, the alkoxy group having 1 to 6 carbon atoms, and the aryl group having 6 to 12 carbon atoms include those exemplified as R 1 of the formula (3), respectively.
  • W 1 is yield strength of the optical film, fracture strain, from the viewpoint of easily improving the elastic modulus and transparency, preferably a single bond, -O -, - CH 2 - , - CH 2 -CH 2 -, - CH (CH 3 )-, -C (CH 3 ) 2 -or-C (CF 3 ) 2- , more preferably single bond, -O-, -CH 2- , -CH (CH 3 )-, -C ( CH 3 ) 2- or -C (CF 3 ) 2- , more preferably single bond, -C (CH 3 ) 2- or -C (CF 3 ) 2- , even more preferably single bond or -C (CF) 3) 2 -, particularly preferably -C (CF 3) 2 - represents a.
  • the formula (26) is the formula (5) :.
  • B is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-,-. It represents COO-, -PO-, -PO 2- , -N ( RB1 )-or-Si ( RB2 ) 2- , and RB1 and RB2 have hydrogen atoms or halogen atoms independently of each other.
  • R 7 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group which may have a halogen atom and a halogen atom independently of each other
  • t represents an alkyl group which may have a halogen atom and a halogen atom.
  • * represents a bond] It is represented by.
  • R 7 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, which may have a halogen atom or a halogen atom independently of each other.
  • Halogen atom may have a halogen atom, an alkyl group, an alkoxy group, the aryl group and aryloxy group, exemplified above are mentioned as R 1 in each formula (3).
  • R 7 is an alkyl group having 1 to 6 carbon atoms which may have a halogen atom independently of each other, and more preferably. It is an alkyl group having 1 to 3 carbon atoms which may have a halogen atom.
  • t represents an integer of 0 to 3 independently of each other, and preferably represents an integer of 0 to 2 from the viewpoint of easily improving the breaking strain, elastic modulus and transparency of the optical film. It preferably represents 0 or 1, and more preferably 0.
  • B is a divalent hydrocarbon group which may have a single bond, —O—, a diphenylmethylene group, and a halogen atom independently of each other, —SO 2-, —S—, —CO. -, -COO-, -PO-, -PO 2- , -N ( RB1 )-or-Si ( RB2 ) 2- represents, and RB1 and RB2 are independent of each other, hydrogen atom or halogen.
  • Examples of the divalent hydrocarbon group which may have a halogen atom, the formula (3) in the R 2 ⁇ of monovalent hydrocarbon group which may have a halogen atom in R 5, further hydrogen atom A divalent group excluding one can be mentioned.
  • a divalent hydrocarbon group, which may have a halogen atom forms a ring in place of two hydrogen atoms among the hydrogen atoms contained in the group, that is, the two hydrogen atoms are replaced by a bonder.
  • the two bonds may be connected to form a ring, and examples of the ring include a cycloalcan ring having 3 to 12 carbon atoms.
  • -N contained B in formula (5) (R B1) - and -Si (R B2) 2 - Examples of the alkyl group which may have a halogen atom in R B1 and R B2 medium, wherein Examples of the alkyl group which may have a halogen atom in R 1 in (3) are mentioned above.
  • B is a divalent hydrocarbon group preferably having a single bond or a halogen atom from the viewpoint of easily improving the transparency, elasticity and bending resistance of the optical film. More preferably a single bond, -CH 2 -, - CH 2 -CH 2 -, - CH (CH 3) -, - C (CH 3) 2 - or -C (CF 3) 2 -, more preferably a single bond , -C (CH 3 ) 2- or -C (CF 3 ) 2- , even more preferably a single bond or -C (CF 3 ) 2- , and particularly preferably -C (CF 3 ) 2- .
  • the formula (5) is the formula (5'):
  • the polyamide-imide resin preferably contains a structure represented by the formula (5') as Y in the formula (1). With such a form, the transparency, elastic modulus and bending resistance of the optical film can be easily improved.
  • the Y in the formula (1) is the structural unit represented by the formula (1).
  • the ratio of the structural units having the structure represented by 5) is preferably 30 mol% or more, more preferably 35 mol, with respect to the total molar amount (100 mol%) of the structural units represented by the formula (1).
  • the proportion of the structural unit in which Y is represented by the formula (5) is at least the above lower limit value, the solubility of the resin in the solvent and the transparency of the optical film can be easily improved.
  • the ratio of the structural units in which Y in the formula (1) is represented by the formula (5) can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
  • Y in the formula (1) when Y in the formula (1) includes a structural unit represented by the formula (5), Y is the structural unit represented by the formula (3) and Y is the structural unit represented by the formula (5).
  • the total ratio with the structural unit represented is preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 90 mol%, based on the total molar amount of the structural unit represented by the formula (1).
  • the above is preferably 100 mol% or less.
  • the total ratio can be measured using, for example, 1 H-NMR, or can be calculated from the raw material charging ratio.
  • X represents a divalent organic group, preferably a divalent organic group having 4 to 40 carbon atoms.
  • X is preferably a divalent aromatic group and a divalent fat. It contains at least one of a cyclic group and a divalent aliphatic group, more preferably a divalent aromatic group.
  • divalent aromatic group for example, one hydrogen atom among the hydrogen atoms in the monovalent aromatic hydrocarbon group exemplified above as R 2 to R 5 in the formula (3) is replaced with a bond.
  • divalent aromatic hydrocarbon groups; one of the divalent aromatic hydrocarbon group, at least one or more linking groups include, for example, groups obtained by binding the linking group such as V 1 of the later.
  • Examples of the divalent alicyclic group such as those of the formula (3) of the hydrogen atoms in the monovalent alicyclic hydrocarbon group exemplified above as R 2 ⁇ R 5 in, one hydrogen atom is bond include one of the divalent alicyclic hydrocarbon group, at least one or more linking groups, for example bound by a linking group such as V 1 of the later group; divalent alicyclic hydrocarbon group replaced with Be done.
  • Examples of the divalent aliphatic groups such as the formula (3) of the hydrogen atoms in the monovalent aliphatic hydrocarbon group exemplified above as R 2 ⁇ R 5 in, replacing one of the hydrogen atoms have bond divalent aliphatic hydrocarbon groups; among the divalent aliphatic hydrocarbon group, at least one or more linking groups include, for example, groups obtained by binding the linking group such as V 1 of the later.
  • X is preferably a divalent organic group having 4 to 40 carbon atoms having a cyclic structure (ali ring, aromatic ring, heterocyclic structure, etc.), and more preferably divalent group having 4 to 40 carbon atoms.
  • the hydrogen atom in the organic group may be substituted with a hydrocarbon group or a hydrocarbon group substituted with fluorine, in which case the number of carbon atoms of the hydrocarbon group and the hydrocarbon group substituted with fluorine is preferable. Is 1-8.
  • the polyamide-imide resin of the present invention may contain a plurality of types of X, and the plurality of types of X may be the same as or different from each other.
  • X is represented by the formula (10), the formula (11), the formula (12), the formula (13), the formula (14), the formula (15), the formula (16), the formula (17) and the formula (18).
  • the hydrogen atom on the ring in the formulas (10) to (18) is substituted with an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms. May be good.
  • An alkyl group having 1 to 6 carbon atoms, the aryl group an alkoxy group and 6 to 12 carbon atoms having 1 to 6 carbon atoms, respectively, exemplified above are mentioned as R 1 of formula (3).
  • V 1 , V 2 and V 3 are independent of each other, single bond, -O-, -S-, -CH 2- , -CH.
  • Q represents a monovalent hydrocarbon group having 1 to 12 carbon atoms which may have a halogen atom.
  • V 1 and V 3 are single bonds, -O- or -S-, and V 2 is -CH 2- , -C (CH 3 ) 2- , -C (CF 3 ) 2. -Or-SO 2- .
  • the bonding positions of V 1 and V 2 with respect to each ring and the bonding positions of V 2 and V 3 with respect to each ring are independent of each other, preferably in the meta position or para position with respect to each ring, and more preferably in the para position. It is a place.
  • the polyamide-imide resin of the present invention is represented by the formula (4): X in the formula (1).
  • A is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-,-.
  • R A1 and R A2 are, independently of one another, may have a hydrogen atom, or a halogen atom
  • R 6 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group independently of each other, which may have a halogen atom or a halogen atom
  • s represents 0 to 4 independently of each other.
  • the structural unit represented by the formula (1) may contain one or more groups represented by the formula (4) as X.
  • R 6 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, which may have a halogen atom or a halogen atom independently of each other.
  • Halogen atom may have a halogen atom, an alkyl group, an alkoxy group, the aryl group, and aryloxy group, respectively, exemplified above are mentioned as R 1 of formula (3).
  • R 6 is preferably an alkyl group having 1 to 6 carbon atoms or a halogen having 1 to 6 carbon atoms from the viewpoint of easily improving the strength, breaking strain, elasticity and transparency of the optical film independently of each other.
  • An alkyl group is more preferably an alkyl group having 1 to 6 carbon atoms or a fluoroalkyl group having 1 to 6 carbon atoms (preferably a perfluoroalkyl group), and more preferably a methyl group, a chloro group or a trifluoromethyl group.
  • s represents an integer of 0 to 4 independently of each other, and is preferably an integer of 1 to 3, more preferably 1 or 2, from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film. More preferably, it is 1.
  • R 6 is substituted at the ortho position relative to —A—, and R 6 is a methyl group, a fluoro group, a chloro group or a tri. It can be a fluoromethyl group.
  • the positions of the joints are preferably the meta-position or the para-position based on -A- from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film independently of each other. , More preferably the para position.
  • A is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-, -PO. -, -PO 2- , -N ( RA1 )-or-Si ( RA2 ) 2- represents, RA1 and RA2 may have a hydrogen atom or a halogen atom independently of each other. Represents a group.
  • divalent hydrocarbon group which may have a halogen atom
  • R 2 ⁇ R monovalent that may have a halogen atom in the 5 hydrocarbon radical of the formula (3)
  • a hydrogen atom 1 Excluded divalent groups can be mentioned.
  • a divalent hydrocarbon group, which may have a halogen atom forms a ring in place of two hydrogen atoms among the hydrogen atoms contained in the group, that is, the two hydrogen atoms are replaced by a bonder.
  • the two bonds may be connected to form a ring, and examples of the ring include a cycloalcan ring having 3 to 12 carbon atoms.
  • equation (4) -N contained A in (R A1) - and -Si (R A2) 2 - Examples of the alkyl group which may have a halogen atom in R A1 and R A2 of the formula ( Examples of the alkyl group which may have a halogen atom in R 1 in 3) are mentioned above.
  • A is yield strength of the optical film, fracture strain, from the viewpoint of easily improving the elastic modulus and transparency, preferably a single bond, -CH 2 -, - CH 2 -CH 2 -, - CH ( CH 3 )-, -C (CH 3 ) 2 -or-C (CF 3 ) 2- , more preferably single bond, -C (CH 3 ) 2- or -C (CF 3 ) 2- , even more preferably.
  • R 6 is a halogen having 1 to 6 carbon atoms independently of each other. Represents an alkyl group, s is 1 or 2, A is a single bond, -C (CH 3 ) 2- or -C (CF 3 ) 2-.
  • the formula (4) is the formula (4') :.
  • the polyamide-imide resin may include a structure represented by the formula (4') as X in the formula (1) from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film. preferable.
  • the ratio of the structural units in which X in the formula (1) is the structure represented by the formula (4) is the total of the structural units represented by the formula (1). With respect to the molar amount (100 mol%), it is preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 80 mol% or more, and preferably 100 mol% or less.
  • the ratio of the structural unit in which X is represented by the formula (4) is at least the above lower limit value, the transparency of the optical film can be easily improved. Further, when it is not more than the above upper limit value, the proof stress of the optical film is likely to be improved.
  • the ratio of the structural units in which X in the formula (1) is represented by the formula (4) can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
  • Z represents a divalent organic group, preferably having a hydrocarbon group having 1 to 8 carbon atoms or a fluorine-substituted hydrocarbon group having 1 to 8 carbon atoms.
  • Examples of the cyclic structure include an alicyclic ring, an aromatic ring, and a heterocyclic structure.
  • divalent organic group having an alicyclic ring and an aromatic ring examples include the formula (20), the formula (21), the formula (22), the formula (23), the formula (24), the formula (25), and the formula (26). Equation (27), Equation (28) and Equation (29):
  • W 1 is a divalent hydrocarbon group (for example, -CH 2- , -CH) which may have a single bond, -O-, a diphenylmethylene group, or a halogen atom.
  • RW1 and RW2 represent an alkyl group that may have a hydrogen atom or a halogen atom independently of each other, and * represents a bond.
  • group bonds represented by examples thereof include a group in which two non-adjacent groups are replaced with hydrogen atoms and a divalent chain hydrocarbon group having 6 or less carbon atoms.
  • divalent organic group having a heterocyclic structure examples include a group having a thiophene ring skeleton.
  • two non-adjacent group bonds represented by the formulas (20) to (29) are hydrogen atoms.
  • a group replaced with and a group having a thiophene ring skeleton are preferable.
  • the Z in the formula (2) includes the formula (20'), the formula (21'), the formula (22'), the formula (23'), the formula (24'), the formula (25'), and the formula (26'). ), Equation (27'), Equation (28') and Equation (29'):
  • W 1 and * are as defined in formula (20) to (29)]
  • the divalent organic group represented by is more preferable.
  • the hydrogen atom on the ring in the formulas (20) to (29) and the formulas (20') to (29') is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. It may be substituted with an aryl group having 6 to 12 carbon atoms.
  • An alkyl group having 1 to 6 carbon atoms, the aryl group an alkoxy group and 6 to 12 carbon atoms having 1 to 6 carbon atoms, respectively, exemplified above are mentioned as R 1 of formula (3).
  • the polyamide-imide resin of the present invention has Z in the formula (2) as the formula (6):
  • W independently of one another, a single bond, -O-, diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2 -, - S - , - It represents CO-, -PO-, -PO 2- , -N ( RC1 )-or-Si ( RC2 ) 2- , and RC1 and RC2 have hydrogen atom or halogen atom independently of each other.
  • R 8 represents an alkyl group which may have a halogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, and p is independent of each other.
  • 0 to 4 represents an integer
  • q represents an integer from 0 to 4
  • * represents a bond.
  • It may include a structure represented by. With such a form, it is easy to improve the proof stress, breaking strain, elastic modulus and transparency of the optical film.
  • the structural unit represented by the formula (2) may contain one or more groups represented by the formula (6) as Z.
  • the bonding position of W is the meta position or the para position with respect to the bonding hand from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film independently of each other. Is preferable, and the para position is more preferable.
  • the formula (6) is the formula (6'):
  • the polyamide-imide resin of the present invention preferably contains a structure represented by the formula (6') as Z in the formula (2). With such a form, it is easy to improve the proof stress, breaking strain, elastic modulus and transparency of the optical film.
  • R 8 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, which may have a halogen atom or a halogen atom independently of each other.
  • Halogen atom may have a halogen atom, an alkyl group, an alkoxy group, the aryl group, and aryloxy group, respectively, exemplified above are mentioned as R 1 of formula (3).
  • R 8 is an alkyl having 1 to 6 carbon atoms, which may preferably have a halogen atom from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film independently of each other. It represents a group or an alkoxy group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms.
  • p represents an integer of 0 to 4 independently of each other, and is preferably an integer of 0 to 2, more preferably 0 or 1, from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film. More preferably, it is 0.
  • W independently of one another, a single bond, -O-, diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2 -, Represents -S-, -CO-, -PO-, -PO 2- , -N ( RC1 )-or -Si ( RC2 ) 2-, and indicates the yield strength, breaking strain, elastic modulus and transparency of the optical film. From the viewpoint of easy improvement, it preferably represents —O— or —S—, and more preferably —O—.
  • RC1 and RC2 represent monovalent hydrocarbon groups having 1 to 12 carbon atoms which may have hydrogen atoms or halogen atoms independently of each other.
  • q is an integer in the range of 0 to 4, and when q is in this range, the proof stress, breaking strain, elastic modulus and transparency of the optical film are improved.
  • Q in the formula (6) and the formula (6') is preferably an integer in the range of 0 to 3, and more preferably an integer in the range of 0 to 2.
  • the structure represented by the formula (6) or the formula (6') in which q is 0 is, for example, a structure derived from terephthalic acid or isophthalic acid, and the structure is, among others, the formula (6) or the formula (6').
  • q is 0
  • p is 1 or 2 (preferably R 8 is an alkyl group having 1 to 3 carbon atoms or a fluorinated alkyl group or an alkoxy group having 1 to 3 carbon atoms). It is preferable that the structure is.
  • the polyamide-imide resin preferably contains a structural unit represented by the formula (2), which includes a structure derived from terephthalic acid.
  • the polyamide-imide resin may contain one or more structural units represented by the formula (6) or the formula (6') as Z in the formula (2).
  • Z in the formula (2) includes a structure represented by the formula (6)
  • X is the formula (6).
  • the ratio of the constituent units represented is preferably 30 mol% or more, more preferably 50 mol% or more, still more preferably 70 mol% or more, based on the total molar amount of the constituent units represented by the formula (2). Yes, preferably 100 mol% or less.
  • the ratio of the structural unit in which Z in the formula (2) is represented by the formula (6) is not more than the above lower limit value, the proof stress, breaking strain, elastic modulus and transparency of the optical film are likely to be improved.
  • the ratio of the structural units in which Z in the formula (2) is represented by the formula (6) can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
  • Z in the formula (2) includes a structure represented by the formula (6)
  • X is the formula (6).
  • the ratio of the constituent units represented is preferably 5 mol% or more, more preferably 15 with respect to the total molar amount of the constituent units represented by the formula (1) and the constituent units represented by the formula (2). It is mol% or more, more preferably 30 mol% or more, particularly preferably 50 mol% or more, and preferably 100 mol% or less.
  • the ratio of the structural unit in which Z in the formula (2) is represented by the formula (6) is not more than the above lower limit value, the proof stress, breaking strain, elastic modulus and transparency of the optical film are likely to be improved.
  • the ratio of the structural units in which Z in the formula (2) is represented by the formula (6) can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
  • the polyamide-imide resin has a structural unit in which Z in the formula (2) is represented by any of the above formulas (20') to (29'), Z in the formula (2) is particularly in the formula (2).
  • the polyamide-imide resin has the following structural unit (d1): in addition to the structural unit represented by the formula (1) and the formula (2).
  • R 24 the alkyl group having 1 to 6 carbon atoms, the alkoxy group having 1 to 6 carbon atoms, and the aryl group having 6 to 12 carbon atoms are exemplified above as R 1 of the formula (3), respectively. Be done.
  • the ratio of the structural unit represented by the formula (d1) is represented by the structural unit represented by the formula (1) and the structural unit represented by the formula (2). It is preferably 0.01 mol% or more, more preferably 0.1 mol% or more, still more preferably 1 mol% or more, and preferably 30 mol% or less, based on the total molar amount of the constituent units. It is preferably 20 mol% or less, more preferably 10 mol% or less.
  • the ratio can be measured using, for example, 1 H-NMR, or can be calculated from the raw material charging ratio.
  • Examples of the X in the formula (2) include those exemplified above as the X in the formula (1), and the preferred form is also the same. Further, X in the formula (1) and X in the formula (2) may be the same or different.
  • the structural unit represented by the formula (1) and / or the structural unit represented by the formula (2) has a structure (or group) represented by the formula (4) as X. It may contain a species or a plurality of species.
  • the ratio of the structural units in which X is represented by the formula (4) is ,
  • the structural unit represented by the formula (1) and the total molar amount of the structural unit represented by the formula (2) are preferably 30 mol% or more, more preferably 50 mol% or more, still more preferably 70. It is mol% or more, preferably 100 mol% or less.
  • the ratio of the structural unit in which X is represented by the formula (4) can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
  • the structural units represented by the formulas (1) and (2) in addition to the structural units represented by the formulas (1) and (2), the structural units represented by the formula (30) and / or the structural units represented by the formula (31). May include.
  • Y 1 represents a tetravalent organic group, and preferably represents an organic group in which the hydrogen atom in the organic group may be substituted with a hydrocarbon group or a hydrocarbon group substituted with fluorine.
  • Examples of Y 1 include formula (20), formula (21), formula (22), formula (23), formula (24), formula (25), formula (26), formula (27), formula (28) and A group represented by the formula (29), a group in which the hydrogen atom in the groups represented by the formulas (20) to (29) is substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group, and a group.
  • a chain hydrocarbon group having 4 or less tetravalent carbon atoms is exemplified.
  • the structural unit represented by the formula (30) may include a structure represented by a plurality of kinds of Y 1, Y 1 of the plurality of species, they being the same or different May be good.
  • Y 2 is a trivalent organic group, preferably an organic group in which the hydrogen atom in the organic group may be substituted with a hydrocarbon group or a hydrocarbon group substituted with fluorine.
  • Examples of Y 2 include the above equations (20), (21), (22), (23), (24), (25), (26), (27), and (28). ) And a group in which any one of the bonds of the group represented by the formula (29) is replaced with a hydrogen atom, and a chain hydrocarbon group having a trivalent carbon number of 6 or less are exemplified.
  • the structural unit represented by the formula (31) may include a structure represented by a plurality of kinds of Y 2, Y 2 a plurality of species, they being the same or different May be good.
  • X 1 and X 2 are divalent organic groups independently of each other, and preferably a hydrocarbon group in which a hydrogen atom in the organic group is substituted with a hydrocarbon group or fluorine. It is an organic group that may be substituted with.
  • Examples of X 1 and X 2 include the above equations (10), (11), (12), (13), (14), (15), (16), (17) and A group represented by the formula (18); a group in which the hydrogen atom in the groups represented by the formulas (10) to (18) is substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; A chain hydrocarbon group having 6 or less carbon atoms is exemplified.
  • the polyamideimide resin contains a structural unit represented by the formula (30) and / or a structural unit represented by the formula (31), the structural unit represented by the formula (30) and the structural unit represented by the formula (31) are represented.
  • the total ratio of the structural units to be formed is preferably 0.01 mol% or more, more preferably 0.01 mol% or more, based on the total molar amount of the structural units represented by the formula (1) and the structural units represented by the formula (2). Is 0.1 mol% or more, more preferably 1 mol% or more, preferably 30 mol% or less, more preferably 20 mol% or less, still more preferably 10 mol% or less.
  • the ratio can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
  • the ratio of the structural units represented by the formula (1) is the total molar amount (100 mol%) of the structural units represented by the formula (1) and the structural units represented by the formula (2).
  • it is preferably 10 mol% or more, more preferably 15 mol% or more, further preferably 20 mol% or more, still more preferably 25 mol% or more, particularly preferably 30 mol% or more, and preferably 90 mol% or more.
  • it is more preferably 70 mol% or less, further preferably 60 mol% or less, and particularly preferably 50 mol% or less.
  • the ratio of the constituent units represented by the formula (1) when the ratio of the constituent units represented by the formula (1) is equal to or higher than the above lower limit value, the thickening due to hydrogen bonds between the amide bonds in the formula (2) is suppressed, and the viscosity of the polyamide-imide varnish Can be reduced, and the manufacture of optical members is easy.
  • the optical film containing the polyamide-imide resin when the ratio of the structural unit represented by the formula (1) is not more than the above upper limit value, the optical film containing the polyamide-imide resin exhibits high surface hardness. Further, when the ratio of the structural unit represented by the formula (1) is not more than the above upper limit value, the ratio of the structural unit represented by the formula (2) increases relatively, so that the polyamide-imide resin is contained. It is easy to improve the yield strength of the optical film made of.
  • the above ratio can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
  • the ratio of the total amount of the structural unit represented by the formula (1) and the structural unit represented by the formula (2) is preferably relative to all the structural units contained in the polyamide-imide resin. It is 50 mol% or more, more preferably 70 mol% or more, further preferably 80 mol% or more, particularly preferably 90 mol% or more, and preferably 100 mol% or less. When the ratio is at least the above lower limit value, the proof stress and transparency of the optical film are likely to be improved.
  • the weight average molecular weight of the polyamide-imide resin of the present invention (hereinafter, may be referred to as Mw) is preferably 100,000 or more, more preferably 150,000 or more, still more preferably 200,000 or more, still more preferably. 300,000 or more, particularly preferably 400,000 or more, particularly more preferably 500,000 or more, particularly preferably 600,000 or more, preferably 1,500,000 or less, more preferably 1,200,000 or less. , More preferably 1,000,000 or less, and particularly preferably 800,000 or less.
  • Mw of the polyamide-imide resin is at least the above lower limit value, it is easy to improve the breaking strain and elastic modulus of the obtained optical film.
  • the polyamide-imide resin of the present invention contains a structure represented by the formula (3) as Y in the formula (1), the viscosity of the solution of the polyamide-imide resin having the structure tends to be high. I understood. Since the viscosity of the resin solution tends to increase as the Mw of the polyamide-imide resin increases, it is very difficult to increase the molecular weight of the polyamide-imide resin containing such a structure.
  • Mw can be increased by producing a polyamide-imide resin under the production conditions described later.
  • Mw can be determined, for example, by performing gel permeation chromatography (hereinafter, may be referred to as GPC) measurement and converting to standard polystyrene, and can be determined, for example, by the method described in Examples.
  • GPC gel permeation chromatography
  • the polyamide-imide resin of the present invention may contain a halogen atom such as a fluorine atom which can be introduced by, for example, the above-mentioned fluorine-containing substituent or the like.
  • a halogen atom such as a fluorine atom which can be introduced by, for example, the above-mentioned fluorine-containing substituent or the like.
  • the halogen atom is preferably a fluorine atom.
  • Preferred fluorine-containing substituents for containing a fluorine atom in the polyamide-imide resin include, for example, a fluoro group and a trifluoromethyl group.
  • the content of halogen atoms in the polyamide-imide resin is preferably 1 to 40% by mass, more preferably 5 to 40% by mass, still more preferably 5 to 30% by mass, based on the mass of the polyamide-imide resin.
  • the halogen atom content is at least the above lower limit value, the YI value of the optical film can be easily reduced, and the breaking strain and elastic modulus can be easily increased.
  • the halogen atom content is less than or equal to the above upper limit, synthesis becomes easier.
  • the imidization ratio of the polyamide-imide resin is preferably 90% or more, more preferably 93% or more, further preferably 96% or more, and usually 100% or less. From the viewpoint of easily improving the optical characteristics of the optical film, the imidization ratio is preferably at least the above lower limit value.
  • the imidization ratio indicates the ratio of the molar amount of imide bond in the polyamide-imide resin to the value twice the molar amount of the structural unit derived from the tetracarboxylic acid compound in the polyamide-imide resin.
  • the value is twice the molar amount of the structural unit derived from the tetracarboxylic acid compound in the polyamide-imide resin, and the molar amount of the structural unit derived from the tricarboxylic acid compound.
  • the ratio of the molar amount of the imide bond in the polyamide-imide resin to the total of the above is shown.
  • the imidization rate can be determined by an IR method, an NMR method, or the like.
  • the method for producing the polyamide-imide resin of the present invention is not particularly limited.
  • a tetracarboxylic acid compound, a dicarboxylic acid compound and a diamine compound which will be described later, can be used as main raw materials. More specifically, a step of reacting a diamine compound with a tetracarboxylic acid compound to obtain a polyamic acid, a step of reacting the polyamic acid with a dicarboxylic acid to obtain a polyamide-imide resin precursor, and a step of obtaining the polyamide-imide resin precursor. It can be produced by a method including a step of imidizing the body. In addition to the tetracarboxylic acid compound and the dicarboxylic acid compound, a tricarboxylic acid compound may be reacted.
  • the structural units represented by the formulas (1) and (30) are usually derived from a diamine compound and a tetracarboxylic acid compound.
  • the structural unit represented by the formula (2) is usually derived from a diamine compound and a dicarboxylic acid compound.
  • the structural unit represented by the formula (31) is usually derived from a diamine compound and a tricarboxylic acid compound.
  • the tetracarboxylic acid compound used in the production of the polyamide-imide resin has at least the formula (X):
  • R 1 to R 5 , m and n are the same as R 1 to R 5 , m and n in formula (3), respectively]. It is preferable to contain the compound represented by.
  • the compound represented by the formula (X) may be obtained by a conventional method, for example, by reacting trimellitic anhydride or a derivative thereof with an aromatic diol, or a commercially available product may be used.
  • the tetracarboxylic acid compound used in the production of the polyamide-imide resin is, in addition to the compound represented by the formula (X), further the formula (Y) :.
  • Examples of the tetracarboxylic acid compound used in the production (or synthesis) of the polyamideimide resin include an aromatic tetracarboxylic acid compound such as an aromatic tetracarboxylic dianhydride; and an aliphatic tetra such as an aliphatic tetracarboxylic dianhydride. Examples include carboxylic acid compounds.
  • the tetracarboxylic acid compound may be used alone or in combination of two or more.
  • the tetracarboxylic dian compound may be a tetracarboxylic dian compound analog such as an acid chloride compound in addition to the dianhydride.
  • aromatic tetracarboxylic dianhydride examples include a non-condensed polycyclic aromatic tetracarboxylic dianhydride, a monocyclic aromatic tetracarboxylic dianhydride, and a condensed polycyclic aromatic tetra.
  • examples include carboxylic dianhydride.
  • examples of the non-condensed polycyclic aromatic tetracarboxylic dianhydride include an ester of trimellitic anhydride and 2,2', 3,3', 5,5'-hexamethyl-4,4'-biphenol.
  • TAHMBP trimellitic anhydride
  • TA23X-BP 2,2', 3,3'-tetramethyl-4,4'-biphenol
  • the monocyclic aromatic tetracarboxylic dianhydride for example, 1,2,4,5-benzenetetracarboxylic dianhydride [also referred to as pyromellitic dianhydride (hereinafter, referred to as PMDA). There is)]
  • examples of the fused polycyclic aromatic tetracarboxylic dianhydride include 2,3,6,7-naphthalenetetracarboxylic dianhydride.
  • TAHMBP TA23X-BP
  • an esterified product of trimellitic anhydride and 3,3', 5,5'-tetramethyl-4,4'-biphenol, PMDA, 4,4'-oxydiphthalic acid preferably TAHMBP, TA23X-BP, an esterified product of trimellitic anhydride and 3,3', 5,5'-tetramethyl-4,4'-biphenol, PMDA, 4,4'-oxydiphthalic acid.
  • Examples of the aliphatic tetracarboxylic dianhydride include cyclic or acyclic aliphatic tetracarboxylic dianhydride.
  • the cyclic aliphatic tetracarboxylic dianhydride is a tetracarboxylic dianhydride having an alicyclic hydrocarbon structure, and specific examples thereof include 1,2,4,5-cyclohexanetetracarboxylic dianhydride.
  • Cycloalkanetetracarboxylic dianhydride such as 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, bicyclo [2.2] .2] Oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, dicyclohexyl-3,3', 4,4'-tetracarboxylic dianhydride and their positional isomers are listed. Be done. These can be used alone or in combination of two or more.
  • acyclic aliphatic tetracarboxylic dianhydride examples include 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-pentanetetracarboxylic dianhydride and the like. These can be used alone or in combination of two or more. Further, a cyclic aliphatic tetracarboxylic dianhydride and an acyclic aliphatic tetracarboxylic dianhydride may be used in combination.
  • trimellitic anhydride and 2,2', 3,3', 5,5'-hexamethyl-4,4' from the viewpoint of easily improving the strength and transparency of the optical film.
  • Esteride with -4,4'-biphenol esterified with trimellitic anhydride and 2,2', 3,3'-tetramethyl-4,4'-biphenol, trimellitic anhydride and 3,3' , 5,5'-Tetramethyl-4,4'-esteride with biphenol, 6FDA and mixtures thereof are more preferred.
  • dicarboxylic acid compound used in the synthesis of the polyamide-imide resin examples include aromatic dicarboxylic acids, aliphatic dicarboxylic acids and their related acid chloride compounds, acid anhydrides, and the like, and two or more of them may be used in combination. Specific examples include terephthalic acid; 2,5-bis (trifluoromethyl) terephthalic acid; isophthalic acid; 2,5-dimethylterephthalic acid; 2,5-dimethoxyterephthalic acid; naphthalenedicarboxylic acid; 4,4'-biphenyl.
  • dicarboxylic acid compounds 4,4'-oxybis benzoic acid, terephthalic acid, isophthalic acid, 2-methoxyterephthalic acid chloride, 2,5-dimethylterephthalic acid, from the viewpoint of easily improving the strength and transparency of the optical film.
  • Acids, 2,5-dimethoxyterephthalic acid, 2,5-bis (trifluoromethyl) terephthalic acid, 2,2'-bis (trifluoromethyl) -4,4'-biphenyldicarboxylic acid and their acid chlorides are preferred.
  • TPC Terephthaloyl chloride
  • isophthaloyl chloride are more preferable, TPC, 2-methoxyterephthalic acid chloride, 2,5-dimethylterephthalic acid chloride, 2,5-dimethoxyterephthalic acid. Chloride is more preferred.
  • the above-mentioned polyamide-imide resin includes other tetracarboxylic acids and tricarboxylic acids, their anhydrides, and their anhydrides, as long as the various physical properties of the optical film are not impaired.
  • the derivative may be further reacted.
  • Examples of other tetracarboxylic acids include water adducts of the anhydrides of the above tetracarboxylic acid compounds.
  • tricarboxylic acid compound examples include aromatic tricarboxylic acids, aliphatic tricarboxylic acids, acid chloride compounds related thereto, acid anhydrides, and the like, and two or more of them may be used in combination.
  • Specific examples include an anhydride of 1,2,4-benzenetricarboxylic acid; 2,3,6-naphthalenetricarboxylic acid-2,3-anhydride; a single bond of phthalic anhydride and benzoic acid, -O- , -CH 2- , -C (CH 3 ) 2- , -C (CF 3 ) 2- , -SO 2- or compounds linked by a phenylene group.
  • diamine compound used for the synthesis of the polyamide-imide resin examples include aliphatic diamines, aromatic diamines and mixtures thereof.
  • aromatic diamine represents a diamine in which an amino group is directly bonded to an aromatic ring, and an aliphatic group or other substituent may be contained in a part of the structure.
  • the aromatic ring may be a monocyclic ring or a condensed ring, and examples thereof include, but are not limited to, a benzene ring, a naphthalene ring, an anthracene ring, and a fluorene ring. Among these, a benzene ring is preferable.
  • the "aliphatic diamine” represents a diamine in which an amino group is directly bonded to an aliphatic group, and an aromatic ring or other substituent may be contained as a part of the structure thereof.
  • aliphatic diamine examples include acyclic aliphatic diamines such as hexamethylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, norbornanediamine and 4,4'.
  • -Cyral aliphatic diamines such as diaminodicyclohexylmethane can be mentioned. These can be used alone or in combination of two or more.
  • aromatic diamine examples include p-phenylenediamine, m-phenylenediamine, 2,4-toluenediamine, m-xylylene diamine, p-xylylene diamine, 1,5-diaminonaphthalene, 2,6-diaminonaphthalene and the like.
  • Aromatic diamine having one aromatic ring 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,3'- Diaminodiphenyl ether, 4,4'-diaminodiphenylsulfone, 3,4′-diaminodiphenylsulfone, 3,3′-diaminodiphenylsulfone, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4) -Aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] Propane, 2,2-bis [4-
  • aromatic diamine preferably 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenylsulfone, 3,3'-Diaminodiphenyl sulfone, 1,4-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2'-dimethylbenzidine, TFMB, 4,4' -Bis (4-aminophenoxy) biphenyl, more preferably 4,4'-di
  • diamine compounds 2,2'-dimethylbenzidine, TFMB, 4,4'-bis (4-aminophenoxy) biphenyl, 6FDAM and 4,4'from the viewpoint of easily improving the proof stress and transparency of the optical film. It is more preferable to use one or more selected from the group consisting of -diaminodiphenyl ether, and it is further preferable to use TFMB and / or 6FDAM.
  • the amount of the diamine compound, the tetracarboxylic acid compound and the dicarboxylic acid compound used can be appropriately selected according to the ratio of each structural unit of the desired resin.
  • the amount of the diamine compound used is preferably 0.94 mol or more, more preferably 0.96 mol or more, with the total molar amount of the tetracarboxylic acid compound and the dicarboxylic acid compound being 1 mol. It is more preferably 0.98 mol or more, particularly preferably 0.99 mol or more, preferably 1.20 mol or less, more preferably 1.10 mol or less, still more preferably 1.05 mol or less, and particularly preferably 1 It is 0.02 mol or less.
  • the amount of the diamine compound used with respect to the tetracarboxylic acid compound and the dicarboxylic acid compound is within the above range, it is easy to obtain a high molecular weight polyamide-imide resin, and it is easy to improve the strength and transparency of the optical film.
  • the reaction temperature of the diamine compound and the tetracarboxylic acid compound is not particularly limited and may be, for example, 5 to 200 ° C., and the reaction time is also not particularly limited and may be, for example, about 30 minutes to 72 hours.
  • the reaction temperature is preferably 5 to 50 ° C., more preferably 5 to 40 ° C., still more preferably 5 to 25 ° C. from the viewpoint of easily obtaining a high molecular weight polyamide-imide resin.
  • the reaction time is preferably 3 to 24 hours, more preferably 5 to 20 hours.
  • the reaction between the diamine compound and the tetracarboxylic acid compound is preferably carried out in a solvent.
  • the solvent is not particularly limited as long as it does not affect the reaction, and is, for example, water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, 1-methoxy-2-propanol, and the like.
  • Alcohol-based solvents such as 2-butoxyethanol and propylene glycol monomethyl ether; ester-based solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, ⁇ -butyrolactone, ⁇ -valerolactone, propylene glycol methyl ether acetate and ethyl lactate; Ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; alicyclic hydrocarbon solvents such as ethyl cyclohexane; toluene and xylene Aromatic hydrocarbon solvents such as; nitrile solvents such as acetonitrile; ether solvents such as tetrahydrofuran and dimethoxye
  • N, N-dimethylformamide (hereinafter, may be referred to as DMF) and other amide solvents; sulfur-containing solvents such as dimethyl sulfone, dimethyl sulfoxide and sulfolane; carbonate solvents such as ethylene carbonate and propylene carbonate; And combinations thereof.
  • an amide-based solvent can be preferably used from the viewpoint of solubility.
  • the solvent used in the reaction is preferably a solvent that has been strictly dehydrated to a water content of 700 ppm or less from the viewpoint of easily obtaining a high molecular weight polyamide-imide resin.
  • the reaction between the diamine compound and the tetracarboxylic acid compound may be carried out under an inert atmosphere such as nitrogen or argon or under reduced pressure, if necessary, and from the viewpoint of easily obtaining a high-molecular-weight polyamide-imide resin, the above-mentioned reaction is carried out. It is preferably carried out with stirring in a tightly controlled dehydration solvent under the same inert atmosphere.
  • the production conditions of the polyamic acid and the dicarboxylic acid may be appropriately selected from the production conditions in the reaction of the diamine compound and the tetracarboxylic acid compound.
  • imidization catalyst used in the imidization step examples include aliphatic amines such as tripropylamine, dibutylpropylamine and ethyldibutylamine; N-ethylpiperidin, N-propylpiperidin, N-butylpyrrolidin, N-butylpiperidine, etc.
  • alicyclic amines such as N-propylhexahydroazepine (monocyclic); azabicyclo [2.2.1] heptane, azabicyclo [3.2.1] octane, azabicyclo [2.2.2] octane, and Alicyclic amines (polycyclic) such as azabicyclo [3.2.2] nonane; and pyridine, 2-methylpyridine (2-picolin), 3-methylpyridine (3-picolin), 4-methylpyridine (4).
  • an acid anhydride together with the imidization catalyst.
  • the acid anhydride include conventional acid anhydrides used in the imidization reaction, and specific examples thereof include acetic anhydride, propionic anhydride, butyric anhydride and other aliphatic acid anhydrides, and phthalic acid and other aromatics. Acid anhydride and the like can be mentioned.
  • the imidization step it is preferable to carry out the imidization step stepwise and raise the temperature to the optimum reaction temperature.
  • stepwise imidizing decomposition of the resin is suppressed, and a high molecular weight polyamide-imide resin can be easily obtained.
  • the reaction temperature for raising the temperature in the stepwise imidization step is preferably 40 to 85 ° C, more preferably 45 to 80 ° C. When the reaction temperature is in the above range, the imidization reaction tends to proceed sufficiently, and Mw tends to rise sufficiently.
  • the reaction time is preferably 30 minutes to 10 hours, more preferably 30 minutes to 5 hours.
  • reaction time When the reaction time is within the above range, it is easy to suppress the decomposition of the resin and the decrease in Mw, and it is easy to suppress the decrease in the imidization rate and the reduction in the molecular weight in the subsequent steps.
  • the imidization step By controlling the imidization step in addition to the above-mentioned synthesis conditions in this way, a high molecular weight resin can be obtained.
  • the polyamide-imide resin may be isolated by separating and purifying it by a conventional method, for example, a separation means such as filtration, concentration, extraction, crystallization, recrystallization, or column chromatography, or a separation means combining these.
  • a separation means such as filtration, concentration, extraction, crystallization, recrystallization, or column chromatography, or a separation means combining these.
  • the resin can be isolated by adding a large amount of alcohol such as methanol to the reaction solution containing the resin, precipitating the resin, and performing concentration, filtration, drying, and the like.
  • the present invention includes an optical film containing the polyamide-imide resin of the present invention.
  • the optical film of the present invention contains a polyamide-imide resin.
  • the optical film of the present invention may contain one kind of polyamide-imide resin, or may contain two or more kinds of polyamide-imide resins.
  • the content of the polyamide-imide resin in the optical film of the present invention is preferably 10 parts by mass or more, more preferably 30 parts by mass or more, still more preferably 50 parts by mass or more, and preferably 50 parts by mass or more, based on 100 parts by mass of the optical film. Is 99.5 parts by mass or less, more preferably 95 parts by mass or less.
  • the optical film of the present invention contains the polyamide-imide resin, both high yield strength and high transparency can be achieved at the same time. Therefore, the polyamide-imide resin and the optical film of the present invention can be suitably used as materials for flexible display devices.
  • transparency can be evaluated by total light transmittance and haze, and when transparency is increased or improved, total light transmittance is high and / or haze is low. That and / or means that the YI value is low.
  • the optical film of the present invention can exhibit high yield strength.
  • the proof stress of the optical film is preferably 90 MPa or more, more preferably 95 MPa or more, further preferably 100 MPa or more, particularly preferably 105 MPa or more, and usually 200 MPa or less.
  • the proof stress is at least the above lower limit value, it is easy to improve the bending resistance, particularly the folding resistance of the optical film.
  • Various physical property values such as elastic modulus have been studied as physical property values that can affect the resistance to bending of the optical film, but according to the studies by the present inventors, it is sufficient to simply improve the elastic modulus. It has been found that folding resistance may not be achieved.
  • the fold resistance can be sufficiently increased by increasing the proof stress of the optical film.
  • the proof stress can be measured with a tensile tester, for example, by the method described in Examples.
  • the total light transmittance of the optical film of the present invention preferably the total light transmittance at a thickness of 40 ⁇ m, is preferably 85% or more, more preferably 88% or more, still more preferably 88%. More than, even more preferably 90% or more, and particularly preferably 91% or more.
  • the upper limit of the total light transmittance is usually 100% or less.
  • the optical film of the present invention usually exhibits a high total light transmittance, the emission intensity of a display element or the like required to obtain a constant brightness is suppressed as compared with the case where a film having a low transmittance is used, for example. It becomes possible. Therefore, power consumption can be reduced.
  • the optical film of the present invention when the optical film of the present invention is incorporated into a display device, a bright display tends to be obtained even if the amount of light from the backlight is reduced, which can contribute to energy saving.
  • the total light transmittance can be measured by using a haze computer in accordance with JIS K 7105: 1981, and can be measured by, for example, the method described in Examples.
  • the total light transmittance may be the total light transmittance in the range of the thickness of the optical film of the present invention.
  • the total light transmittance may be the total light transmittance in the range of the thickness of the optical film described later.
  • the optical film when the optical film is excellent in optical characteristics, it means that the total light transmittance is high and / or the haze is low and / or the YI value is low, and the transparency is high. May be used interchangeably as it increases or improves.
  • the haze of the optical film of the present invention is preferably 2.0% or less, more preferably 1.5% or less, still more preferably 1.0%. Below, it is even more preferably 0.8% or less, particularly preferably 0.5% or less, particularly more preferably 0.3% or less, and usually 0% or more.
  • the haze of the optical film is not more than the above upper limit value, the transparency of the optical film can be improved, and high visibility can be exhibited when used for, for example, the front plate of a display device.
  • the haze can be measured using a haze computer or the like in accordance with JIS K 7136: 2000, and can be measured by, for example, the method described in Examples. Further, in the present specification, the haze may be in the range of the thickness of the optical film described later.
  • the YI value of the optical film of the present invention is preferably less than 3.0, more preferably 2.8 or less, still more preferably 2.5 or less.
  • the YI value of the optical film is not more than the above upper limit value, the transparency of the optical film can be improved, and high visibility can be exhibited when used for the front plate of a display device or the like.
  • the yellowness is usually ⁇ 5 or higher, preferably ⁇ 2 or higher.
  • the elastic modulus of the optical film of the present invention is preferably 5.0 GPa or more, more preferably 5.5 GPa or more, still more preferably 6.0 GPa or more, and usually 15 GPa or less.
  • the elastic modulus is at least the above lower limit value, it is easy to suppress the deformation of the optical film and it is easy to improve the durability.
  • the elastic modulus can be measured using a tensile tester, for example, by the method described in Examples.
  • the elastic modulus is a value at 25 ° C.
  • the number of times of folding of the optical film of the present invention in the MIT folding fatigue test conforming to ASTM standard D2176-16 is preferably 80,000 times or more, more preferably 100,000 times or more. More preferably 200,000 times or more, and particularly preferably 250,000 times or more.
  • the MIT fold resistance fatigue test can be measured using a MIT fold resistance fatigue tester, for example, by the method described in Examples.
  • the optical film of the present invention has a high level of transparency and thus can exhibit high total light transmittance and low haze even if the thickness is relatively large.
  • the thickness of the optical film of the present invention is preferably 10 ⁇ m or more, more preferably 15 ⁇ m or more, still more preferably 20 ⁇ m or more, still more preferably 30 ⁇ m or more, particularly preferably 35 ⁇ m or more, and particularly preferably 40 ⁇ m or more. It is preferably 100 ⁇ m or less, more preferably 80 ⁇ m or less, and further preferably 60 ⁇ m or less.
  • the thickness of the optical film can be measured with a thickness gauge or the like, for example, by the method described in Examples.
  • the optical film of the present invention may contain at least one filler in addition to the polyamide-imide resin.
  • the filler include organic particles and inorganic particles, and preferably inorganic particles.
  • the inorganic particles include metal oxide particles such as silica, zirconia, alumina, titania, zinc oxide, germanium oxide, indium oxide, tin oxide, indium tin oxide (ITO), antimony oxide, and cerium oxide, magnesium fluoride, and fluoride.
  • metal fluoride particles such as sodium chemicals, and among these, silica particles, zirconia particles, and alumina particles are preferable from the viewpoint of easily improving the strength, elasticity, and transparency of the optical film, and more preferably.
  • Examples include silica particles. These fillers can be used alone or in combination of two or more.
  • the average primary particle size of the filler preferably silica particles
  • the average primary particle size of the filler is usually 1 nm or more, preferably 5 nm or more, more preferably 10 nm or more, still more preferably 15 nm or more, particularly preferably 20 nm or more, preferably 100 nm or less, more preferably. It is 90 nm or less, more preferably 80 nm or less, even more preferably 70 nm or less, particularly preferably 60 nm or less, particularly more preferably 50 nm or less, and particularly preferably 40 nm or less.
  • the average primary particle size of the silica particles is within the above range, the strength, elastic modulus and transparency of the optical film can be easily improved.
  • the average primary particle size of the filler can be measured by the BET method.
  • the average primary particle size may be measured by image analysis of a transmission electron microscope or a scanning electron microscope.
  • the content of the filler is usually 0.1% by mass or more, preferably 1% by mass or more, more preferably 5 with respect to the mass of the optical film. It is mass% or more, more preferably 10% by mass or more, even more preferably 20% by mass or more, particularly preferably 30% by mass or more, and preferably 60% by mass or less.
  • the filler content is at least the above lower limit value, the proof stress, elastic modulus and transparency of the optical film are likely to be improved. Further, when the content of the filler is not more than the above upper limit value, the optical characteristics of the optical film can be easily improved.
  • the optical film of the present invention may further contain an ultraviolet absorber.
  • the ultraviolet absorber can be appropriately selected from those usually used as an ultraviolet absorber in the field of resin materials.
  • the ultraviolet absorber may contain a compound that absorbs light having a wavelength of 400 nm or less.
  • Examples of the ultraviolet absorber include at least one compound selected from the group consisting of benzophenone compounds, salicylate compounds, benzotriazole compounds, and triazine compounds.
  • the UV absorber can be used alone or in combination of two or more. Since the optical film contains an ultraviolet absorber, deterioration of the resin is suppressed, so that visibility can be improved when the optical film is applied to an image display device or the like.
  • system compound refers to a derivative of a compound to which the "system compound” is attached.
  • the "benzophenone-based compound” refers to a compound having benzophenone as a maternal skeleton and a substituent attached to benzophenone.
  • the content of the ultraviolet absorber is preferably 1% by mass or more, more preferably 2% by mass or more, still more preferably 3% by mass or more, based on the mass of the optical film. Yes, preferably 10% by mass or less, more preferably 8% by mass or less, still more preferably 6% by mass or less.
  • the suitable content varies depending on the UV absorber used, but if the content of the UV absorber is adjusted so that the light transmittance at 400 nm is about 20 to 60%, the light resistance of the optical film is enhanced and the transparency is improved. Easy to increase.
  • the optical film of the present invention may further contain additives other than the filler and the ultraviolet absorber.
  • additives include, for example, antioxidants, mold release agents, stabilizers, bluing agents, flame retardants, pH regulators, silica dispersants, lubricants, thickeners, leveling agents and the like.
  • the content thereof is preferably 0.001 to 20% by mass, more preferably 0.01 to 15% by mass, still more preferably 0.1 to 100% by mass, based on the mass of the optical film. It may be 10% by mass.
  • the use of the optical film of the present invention is not particularly limited, and it may be used for various purposes.
  • the optical film of the present invention may be a single layer or a laminated body, the optical film of the present invention may be used as it is, or may be used as a laminated body with another film. ..
  • the optical film is a laminated body, it is referred to as an optical film including all the layers laminated on one side or both sides of the optical film.
  • the optical film of the present invention is a laminated body, it is preferable to have one or more functional layers on at least one surface of the optical film.
  • the functional layer include a hard coat layer, a primer layer, a gas barrier layer, an ultraviolet absorbing layer, an adhesive layer, a hue adjusting layer, and a refractive index adjusting layer.
  • the functional layer can be used alone or in combination of two or more.
  • the thickness of the hard coat layer is not particularly limited, and may be, for example, 2 to 100 ⁇ m. When the thickness of the hard coat layer is within the above range, the impact resistance can be enhanced, the bending resistance is less likely to decrease, and the problem of curl generation due to curing shrinkage tends to be less likely to occur.
  • the hard coat layer can be formed by curing a hard coat composition containing a reactive material capable of forming a crosslinked structure by irradiation with active energy rays or by applying thermal energy, and is preferably formed by irradiation with active energy rays.
  • Active energy rays are defined as energy rays that can generate active species by decomposing compounds that generate active species, and are visible light, ultraviolet rays, infrared rays, X-rays, ⁇ rays, ⁇ rays, ⁇ rays, and electron beams. And the like, preferably ultraviolet rays.
  • the hard coat composition contains at least one polymer of a radically polymerizable compound and a cationically polymerizable compound.
  • the radically polymerizable compound is a compound having a radically polymerizable group.
  • the radically polymerizable group contained in the radically polymerizable compound may be a functional group capable of causing a radical polymerization reaction, and examples thereof include a group containing a carbon-carbon unsaturated double bond, and specifically, a vinyl group. , (Meta) acryloyl group and the like.
  • the radically polymerizable compound has two or more radically polymerizable groups, these radically polymerizable groups may be the same or different from each other.
  • the number of radically polymerizable groups contained in one molecule of the radically polymerizable compound is preferably 2 or more from the viewpoint of improving the hardness of the hard coat layer.
  • Examples of the radically polymerizable compound include compounds having a (meth) acryloyl group from the viewpoint of high reactivity, and specifically, 2 to 6 (meth) acryloyl groups in one molecule.
  • Compounds called polyfunctional acrylate monomers and epoxy (meth) acrylates, urethane (meth) acrylates, and polyester (meth) acrylates have a molecular weight of several hundreds of (meth) acryloyl groups in the molecule.
  • Thousands of oligomers are mentioned, preferably one or more selected from epoxy (meth) acrylates, urethane (meth) acrylates and polyester (meth) acrylates.
  • the cationically polymerizable compound is a compound having a cationically polymerizable group such as an epoxy group, an oxetanyl group, and a vinyl ether group.
  • the number of cationically polymerizable groups contained in one molecule of the cationically polymerizable compound is preferably 2 or more, and more preferably 3 or more, from the viewpoint of improving the hardness of the hard coat layer.
  • a compound having at least one epoxy group and an oxetanyl group as the cationically polymerizable group is preferable.
  • a cyclic ether group such as an epoxy group or an oxetanyl group is preferable because the shrinkage associated with the polymerization reaction is small. Further, among the cyclic ether groups, compounds having an epoxy group are easily available, compounds having various structures are easily available, the durability of the obtained hard coat layer is not adversely affected, and compatibility with radically polymerizable compounds is easily controlled. There is an advantage. Further, among the cyclic ether groups, the oxetanyl group tends to have a higher degree of polymerization than the epoxy group, accelerates the network formation rate obtained from the cationically polymerizable compound of the obtained hard coat layer, and is mixed with the radically polymerizable compound.
  • the cationically polymerizable compound having an epoxy group examples include polyglycidyl ether of a polyhydric alcohol having an alicyclic ring, or a cyclohexene ring or cyclopentene ring-containing compound with an appropriate oxidizing agent such as hydrogen peroxide or peracid.
  • Alicyclic epoxy resin obtained by epoxidation polyglycidyl ether of aliphatic polyhydric alcohol or its alkylene oxide adduct, polyglycidyl ester of aliphatic long chain polybasic acid, homopolymer of glycidyl (meth) acrylate, An aliphatic epoxy resin such as a copolymer; a glycidyl ether produced by reacting bisphenols such as bisphenol A, bisphenol F and hydrogenated bisphenol A, or derivatives such as their alkylene oxide adducts and caprolactone adducts with epichlorohydrin. And glycidyl ether type epoxy resin which is a novolak epoxy resin and is derived from bisphenols and the like.
  • the hard coat composition may further contain a polymerization initiator.
  • the polymerization initiator include a radical polymerization initiator, a cationic polymerization initiator, a radical and a cationic polymerization initiator, and the like, which are appropriately selected and used. These polymerization initiators are decomposed by at least one of active energy ray irradiation and heating to generate radicals or cations to promote radical polymerization and cation polymerization.
  • the radical polymerization initiator may be any as long as it can release a substance that initiates radical polymerization by at least one of irradiation with active energy rays and heating.
  • thermal radical polymerization initiator examples include organic peroxides such as hydrogen peroxide and perbenzoic acid, and azo compounds such as azobisbutyronitrile.
  • Active energy ray radical polymerization initiators include Type 1 radical polymerization initiators, which generate radicals by decomposition of molecules, and Type 2 radical polymerization initiators, which coexist with tertiary amines and generate radicals by hydrogen abstraction type reactions. Yes, they are used alone or in combination.
  • the cationic polymerization initiator may be any one as long as it can release a substance that initiates cationic polymerization by at least one of activation energy ray irradiation and heating.
  • an aromatic iodonium salt an aromatic sulfonium salt, a cyclopentadienyl iron (II) complex and the like can be used. These can initiate cationic polymerization by either irradiation with active energy rays or heating, depending on the difference in structure.
  • the polymerization initiator can preferably contain 0.1 to 10% by mass with respect to 100% by mass of the entire hard coat composition.
  • the content of the polymerization initiator is in the above range, curing can proceed sufficiently, and the mechanical properties and adhesive strength of the finally obtained coating film can be in a good range. Poor adhesive strength due to curing shrinkage, cracking phenomenon, and curling phenomenon tend to be less likely to occur.
  • the hard coat composition may further comprise one or more selected from the group consisting of solvents and additives.
  • the solvent can dissolve or disperse the polymerizable compound and the polymerization initiator, and any solvent known as a solvent for hard coat compositions in the present art does not impair the effects of the present invention. In the range, it can be used.
  • the additive may further contain inorganic particles, a leveling agent, a stabilizer, a surfactant, an antistatic agent, a lubricant, an antifouling agent and the like.
  • the ultraviolet absorbing layer is a layer having an ultraviolet absorbing function.
  • a main material selected from an ultraviolet curable transparent resin, an electron beam curable transparent resin, and a thermosetting transparent resin, and the main material thereof. It is composed of a dispersed ultraviolet absorber.
  • the adhesive layer is a layer having an adhesive function, and has a function of adhering an optical film to another member.
  • a material for forming the adhesive layer a commonly known material can be used.
  • a thermosetting resin composition or a photocurable resin composition can be used.
  • the thermosetting resin composition or the photocurable resin composition can be polymerized and cured by supplying energy after the fact.
  • the adhesive layer may be a layer called a pressure-sensitive adhesive (Pressure Sensitive Adhesive, PSA), which is attached to an object by pressing.
  • PSA Pressure Sensitive Adhesive
  • the pressure-sensitive adhesive may be an adhesive that is "a substance that has adhesiveness at room temperature and adheres to an adherend with a light pressure" (JIS K 6800), and “protects a specific component (microcapsules). ), And an adhesive that can maintain stability until the film is destroyed by an appropriate means (pressure, heat, etc.) ”(JIS K 6800).
  • the hue adjustment layer is a layer having a hue adjustment function, and is a layer capable of adjusting the optical film to a desired hue.
  • the hue adjusting layer is, for example, a layer containing a resin and a colorant.
  • this colorant include inorganic pigments such as titanium oxide, zinc oxide, petals, titanium oxide-based calcined pigments, ultramarine, cobalt aluminate, and carbon black; azo compounds, quinacridone compounds, anthracinone compounds, and the like.
  • Organic pigments such as perylene compounds, isoindolinone compounds, phthalocyanine compounds, quinophthalone compounds, slene compounds, and diketopyrrolopyrrole compounds; extender pigments such as barium sulfate and calcium carbonate; and basic dyes, Examples thereof include dyes such as acidic dyes and medium dyes.
  • the refractive index adjusting layer is a layer having a function of adjusting the refractive index, for example, a layer having a refractive index different from that of a single-layer optical film and capable of imparting a predetermined refractive index to the optical film.
  • the refractive index adjusting layer may be, for example, a resin layer appropriately selected and, in some cases, a resin layer further containing a pigment, or a thin film of metal.
  • the pigment for adjusting the refractive index include silicon oxide, aluminum oxide, antimony oxide, tin oxide, titanium oxide, zirconium oxide and tantalum oxide.
  • the average primary particle size of the pigment may be 0.1 ⁇ m or less.
  • the metal used for the refractive index adjusting layer include metals such as titanium oxide, tantalum oxide, zirconium oxide, zinc oxide, tin oxide, silicon oxide, indium oxide, titanium oxynitride, titanium nitride, silicon oxynitride, and silicon nitride. Oxides or metal nitrides can be mentioned.
  • the optical film may have a protective film on at least one side (one side or both sides).
  • the protective film may be laminated on the surface on the optical film side or the surface on the functional layer side, and is laminated on both the optical film side and the functional layer side. You may.
  • the protective film may be laminated on the surface on one functional layer side or on the surfaces on both functional layer sides.
  • the protective film is a film for temporarily protecting the surface of the optical film or the functional layer, and is not particularly limited as long as it is a peelable film capable of protecting the surface of the optical film or the functional layer.
  • the protective film examples include polyester resin films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefin resin films such as polyethylene and polypropylene films, acrylic resin films, and the like, and polyolefin resin films and polyethylene. It is preferable to select from the group consisting of a terephthalate resin film and an acrylic resin film. When the optical film has two protective films, each protective film may be the same or different.
  • the thickness of the protective film is not particularly limited, but is usually 10 to 120 ⁇ m, preferably 15 to 110 ⁇ m, and more preferably 20 to 100 ⁇ m. When the optical film has two protective films, the thickness of each protective film may be the same or different.
  • the optical film of the present invention is not particularly limited, but for example, the following steps: (A) A step of preparing a liquid containing the polyamide-imide resin (sometimes referred to as a resin varnish) (varnish preparation step), (B) A step of applying a resin varnish to a base material to form a coating film (coating step), and (c) a step of drying the applied liquid (coating film) to form an optical film (optical film formation).
  • a step of preparing a liquid containing the polyamide-imide resin sometimes referred to as a resin varnish
  • varnish preparation step A step of applying a resin varnish to a base material to form a coating film
  • coating step a coating film
  • It can be manufactured by a method including.
  • the polyamide-imide resin is dissolved in a solvent, and if necessary, the additive is added and stirred and mixed to prepare a resin varnish.
  • the solvent used for preparing the resin varnish is not particularly limited as long as the resin can be dissolved.
  • a solvent include amide solvents such as DMAc and DMF; lactone solvents such as ⁇ -butyrolactone and ⁇ -valerolactone; sulfur-containing solvents such as dimethyl sulfoxide, dimethyl sulfoxide and sulfolane; ethylene carbonate, propylene carbonate and the like. Carbonated solvents; and combinations thereof.
  • an amide solvent or a lactone solvent is preferable.
  • These solvents can be used alone or in combination of two or more.
  • the resin varnish may contain water, an alcohol solvent, a ketone solvent, an acyclic ester solvent, an ether solvent and the like.
  • the solid content concentration of the varnish is preferably 1 to 25% by mass, more preferably 5 to 15% by mass. In the present specification, the solid content of the varnish indicates the total amount of the components of the varnish excluding the solvent.
  • a varnish is applied onto the substrate by a known coating method to form a coating film.
  • Known coating methods include, for example, wire bar coating method, reverse coating, roll coating method such as gravure coating, die coating method, comma coating method, lip coating method, spin coating method, screen coating method, fountain coating method, dipping method, and the like. Examples include a spray method and a salivation molding method.
  • the optical film can be formed by drying the coating film and peeling it from the substrate. After the peeling, a drying step of further drying the optical film may be performed. Drying of the coating film is usually 50 ⁇ 350 ° C., the good Mashiku can be carried out at a temperature of 50 ⁇ 230 ° C.. In a preferred embodiment of the present invention, it is preferable to carry out drying step by step.
  • a varnish containing a high molecular weight resin tends to have a high viscosity, and it is generally difficult to obtain a uniform film, and it is difficult to obtain a film having excellent transparency. Therefore, the varnish containing the high molecular weight resin can be uniformly dried by performing the drying step by step.
  • the coating film may be dried under an inert atmosphere or under reduced pressure conditions. Further, when the optical film is dried under vacuum conditions, minute bubbles may be generated and remain in the film, which causes deterioration of optical characteristics. Therefore, it is preferable to perform the drying under atmospheric pressure.
  • Examples of the base material include PET film, PEN film, other polyimide-based resin, polyamide-based resin film, and the like.
  • PET film, PEN film and the like are preferable from the viewpoint of excellent heat resistance, and PET film is more preferable from the viewpoint of adhesion to the optical film and cost.
  • the optical film of the present invention can be suitably used as a front plate of a display device, particularly a flexible display device (sometimes referred to as a window film), particularly a front plate of a rollable display or a foldable display. That is, the optical film of the present invention is preferably a film for the front plate of a flexible display device.
  • the front plate has a function of protecting the display element of the flexible display device.
  • the flexible display device is a display device that is used with operations such as repeatedly bending and repeatedly winding the image display device.
  • the front plate of a flexible display device used with such repeated bending operations is required to have high bending resistance, particularly folding resistance.
  • the front plate is also required to have high visibility.
  • the front plate of the image display device is required to have high visibility and high visibility.
  • High bending resistance is required.
  • the film of the present invention preferably has the total light transmittance, haze and / or YI value as described above from the viewpoint of easily enhancing visibility when used for the front plate of a flexible display device. Further, from the viewpoint of easily improving the bending resistance, particularly the folding resistance when used as the front plate of the flexible display device, it is preferable to satisfy the number of folding resistances in the MIT folding resistance test as described above.
  • Examples of display devices include wearable devices such as televisions, smartphones, mobile phones, car navigation systems, tablet PCs, portable game machines, electronic papers, indicators, bulletin boards, watches, and smart watches.
  • Examples of the flexible display include display devices having flexible characteristics, such as televisions, smartphones, mobile phones, and smart watches.
  • Examples of the flexible display device include all image display devices having flexible characteristics, and examples thereof include the rollable display and the foldable display as described above.
  • the rollable display is an image display device in which an image display portion including a front plate is wound in a roll shape, and the image display portion is pulled out to form a flat surface or a curved surface, and is wound in a roll shape. It is an image display device in which operations such as taking are performed each time it is used.
  • a foldable display is an image display device in which an image display portion including a front plate is bent and is used in a state where the image display portion is opened and made into a flat surface or a curved surface, and an operation such as folding is used. It is an image display device that is performed every time. An image display device in which such operations such as winding and bending are repeatedly performed is referred to as a flexible display device.
  • the present invention includes a flexible display device comprising the optical film of the present invention.
  • the optical film of the present invention is preferably used as a front plate in a flexible display device, and the front plate may be referred to as a window film.
  • the flexible display device includes a laminate for a flexible display device and an organic EL display panel, and the laminate for the flexible display device is arranged on the visual side with respect to the organic EL display panel and is configured to be bendable.
  • the laminated body for the flexible display device may further contain a polarizing plate and a touch sensor, and the stacking order thereof is arbitrary, but from the visual side, a window film, a polarizing plate, a touch sensor or a window film, and a touch sensor.
  • the polarizing plates are laminated in this order. If a polarizing plate is present on the visual side of the touch sensor, the pattern of the touch sensor is less likely to be visually recognized and the visibility of the displayed image is improved, which is preferable.
  • Each member can be laminated using an adhesive, an adhesive, or the like. Further, a light-shielding pattern formed on at least one surface of any layer of the window film, the polarizing plate, and the touch sensor can be provided.
  • the flexible display device of the present invention preferably further includes a polarizing plate, particularly a circular polarizing plate.
  • the circular polarizing plate is a functional layer having a function of transmitting only a right circularly polarized light component or a left circularly polarized light component by laminating a ⁇ / 4 retardation plate on a linear polarizing plate.
  • the external light is converted to right-handed circularly polarized light, reflected by the organic EL panel to block the left-handed circularly polarized light, and only the light emitting component of the organic EL is transmitted to suppress the influence of the reflected light. It is used to make it easier to see.
  • the absorption axis of the linear polarizing plate and the slow axis of the ⁇ / 4 retardation plate must theoretically be 45 °, but practically, they are 45 ⁇ 10 °.
  • the linear polarizing plate and the ⁇ / 4 retardation plate do not necessarily have to be laminated adjacent to each other, and the relationship between the absorption axis and the slow phase axis may satisfy the above range. It is preferable to achieve perfect circularly polarized light at all wavelengths, but it is not always necessary in practical use. Therefore, the circularly polarizing plate in the present invention also includes an elliptical polarizing plate. It is also preferable to further laminate a ⁇ / 4 retardation film on the visible side of the linear polarizing plate to convert the emitted light into circularly polarized light to improve the visibility when wearing polarized sunglasses.
  • the linear polarizing plate is a functional layer that allows light vibrating in the transmission axis direction to pass through, but has the function of blocking the polarization of vibration components perpendicular to it.
  • the linear polarizing plate may be configured to include a linear polarizing element alone or a linear polarizing element and a protective film attached to at least one surface thereof.
  • the thickness of the linear polarizing plate may be 200 ⁇ m or less, preferably 0.5 to 100 ⁇ m. When the thickness of the linear polarizing plate is within the above range, the flexibility of the linear polarizing plate tends to be difficult to decrease.
  • the linear polarizer may be a film-type polarizer produced by dyeing and stretching a polyvinyl alcohol (hereinafter, may be abbreviated as PVA) -based film.
  • a dichroic dye such as iodine is adsorbed on the PVA-based film oriented by stretching, or the dichroic dye is oriented in a state of being adsorbed on the PVA to exhibit polarization performance.
  • other steps such as swelling, cross-linking with boric acid, washing with an aqueous solution, and drying may be included.
  • the stretching and dyeing steps may be performed on the PVA-based film alone, or may be performed in a state of being laminated with another film such as polyethylene terephthalate.
  • the thickness of the PVA-based film used is preferably 10 to 100 ⁇ m, and the draw ratio is preferably 2 to 10 times.
  • a liquid crystal coating type polarizer formed by coating a liquid crystal polarizing composition.
  • the liquid crystal polarizing composition may contain a liquid crystal compound and a dichroic dye compound.
  • the liquid crystal compound may have a property of exhibiting a liquid crystal state, and is particularly preferable when it has a higher-order orientation state such as a smectic phase because it can exhibit high polarization performance.
  • the liquid crystal compound preferably has a polymerizable functional group.
  • the dichroic dye compound is a dye that is oriented together with the liquid crystal compound to exhibit dichroism, and may have a polymerizable functional group, and the dichroic dye itself has a liquid crystal property. May be. Any of the compounds contained in the liquid crystal polarizing composition has a polymerizable functional group.
  • the liquid crystal polarizing composition can further contain an initiator, a solvent, a dispersant, a leveling agent, a stabilizer, a surfactant, a cross-linking agent, a silane coupling agent and the like.
  • the liquid crystal polarizing layer is manufactured by applying a liquid crystal polarizing composition on an alignment film to form a liquid crystal polarizing layer.
  • the liquid crystal polarizing layer can be formed to be thinner than the film-type polarizing element, and the thickness is preferably 0.5 to 10 ⁇ m, more preferably 1 to 5 ⁇ m.
  • the alignment film is produced, for example, by applying an alignment film forming composition on a base material and imparting orientation by rubbing, polarized light irradiation, or the like.
  • the alignment film forming composition contains an alignment agent, and may further contain a solvent, a cross-linking agent, an initiator, a dispersant, a leveling agent, a silane coupling agent, and the like.
  • the alignment agent include polyvinyl alcohols, polyacrylates, polyamic acids, and polyimides.
  • an orientation agent that imparts orientation by polarization irradiation it is preferable to use an orientation agent containing a synnamate group.
  • the Mw of the polymer used as the alignment agent is, for example, about 10,000 to 1,000,000.
  • the thickness of the alignment film is preferably 5 to 10,000 nm, and more preferably 10 to 500 nm in that the alignment regulating force is sufficiently exhibited.
  • the liquid crystal polarizing layer can be peeled off from the base material, transferred and laminated, or the base material can be laminated as it is. It is also preferable that the base material serves as a transparent base material for a protective film, a retardation plate, and a window film.
  • any transparent polymer film may be used, and the same materials and additives used for the transparent base material of the window film can be used. Further, it may be a coating type protective film obtained by applying a cationic curing composition such as an epoxy resin or a radical curing composition such as acrylate and curing the film.
  • the protective film may be a plasticizer, an ultraviolet absorber, an infrared absorber, a colorant such as a pigment or a dye, a fluorescent whitening agent, a dispersant, a heat stabilizer, a light stabilizer, an antioxidant, an antioxidant, if necessary. , Lubricants, solvents and the like may be contained.
  • the thickness of the protective film is preferably 200 ⁇ m or less, more preferably 1 to 100 ⁇ m. When the thickness of the protective film is in the above range, the flexibility of the film tends to be difficult to decrease.
  • the ⁇ / 4 retardation plate is a film that gives a retardation of ⁇ / 4 in a direction orthogonal to the traveling direction of incident light (in-plane direction of the film).
  • the ⁇ / 4 retardation plate may be a stretch-type retardation plate manufactured by stretching a polymer film such as a cellulose-based film, an olefin-based film, or a polycarbonate-based film.
  • the ⁇ / 4 retardation plate may be used as a retardation adjuster, a plastic agent, an ultraviolet absorber, an infrared absorber, a colorant such as a pigment or a dye, a fluorescent whitening agent, a dispersant, a heat stabilizer, and a light stabilizer.
  • the thickness of the stretched retardation plate is preferably 200 ⁇ m or less, more preferably 1 to 100 ⁇ m.
  • the thickness of the stretchable retardation plate is within the above range, the flexibility of the stretchable retardation plate tends to be difficult to decrease.
  • the ⁇ / 4 retardation plate there is a liquid crystal coating type retardation plate formed by coating a liquid crystal composition.
  • the liquid crystal composition contains a liquid crystal compound exhibiting a liquid crystal state such as nematic, cholesteric, and smectic.
  • the liquid crystal compound has a polymerizable functional group.
  • the liquid crystal composition can further contain an initiator, a solvent, a dispersant, a leveling agent, a stabilizer, a surfactant, a cross-linking agent, a silane coupling agent, and the like.
  • the liquid crystal coating type retardation plate can be manufactured by applying a liquid crystal composition on a substrate and curing the liquid crystal composition to form a liquid crystal retardation layer, similarly to the liquid crystal polarizing layer.
  • the liquid crystal coating type retardation plate can be formed to be thinner than the stretch type retardation plate.
  • the thickness of the liquid crystal polarizing layer is preferably 0.5 to 10 ⁇ m, more preferably 1 to 5 ⁇ m.
  • the liquid crystal coating type retardation plate can be peeled off from the base material, transferred and laminated, or the base material can be laminated as it is. It is also preferable that the base material serves as a transparent base material for a protective film, a retardation plate, and a window film.
  • the in-plane phase difference is preferably 100 to 4 so that it becomes ⁇ / 4 with respect to the vicinity of 560 nm, which has high visual sensitivity. It is designed to be 180 nm, more preferably 130-150 nm.
  • a reverse dispersion ⁇ / 4 retardation plate using a material having a birefringence wavelength dispersion characteristic opposite to the usual one is preferable in that visibility is improved.
  • a stretchable retardation plate can be used as described in JP-A-2007-232873, and a liquid crystal-coated retardation plate can be used as described in JP-A-2010-30979. ..
  • a technique for obtaining a wideband ⁇ / 4 retardation plate by combining with a ⁇ / 2 retardation plate is also known (for example, Japanese Patent Application Laid-Open No. 10-90521).
  • the ⁇ / 2 retardation plate is also manufactured by the same material method as the ⁇ / 4 retardation plate.
  • the combination of the stretchable retardation plate and the liquid crystal coating type retardation plate is arbitrary, but the thickness can be reduced by using the liquid crystal coating type retardation plate in both cases.
  • a method of laminating a positive C plate on the circularly polarizing plate in order to improve visibility in an oblique direction is known (for example, Japanese Patent Application Laid-Open No. 2014-224738).
  • the positive C plate may be a liquid crystal coating type retardation plate or a stretched retardation plate.
  • the phase difference in the thickness direction of the retardation plate is preferably ⁇ 200 to ⁇ 20 nm, more preferably ⁇ 140 to ⁇ 40 nm.
  • the flexible display device of the present invention preferably further includes a touch sensor.
  • the touch sensor is used as an input means.
  • Examples of the touch sensor include various types such as a resistive film method, a surface acoustic wave method, an infrared method, an electromagnetic induction method, and a capacitance method, and a capacitance method is preferable.
  • the capacitive touch sensor is divided into an active region and an inactive region located outside the active region.
  • the active area is an area corresponding to the area where the screen is displayed on the display panel (display unit), the area where the user's touch is detected, and the inactive area is the area where the screen is not displayed on the display device (non-active area). This is the area corresponding to the display unit).
  • the touch sensor is formed in a substrate having flexible characteristics, a sensing pattern formed in an active region of the substrate, and an inactive region of the substrate, and is connected to an external drive circuit via the sensing pattern and a pad portion.
  • Each sensing line for can be included.
  • the substrate having flexible characteristics the same material as the transparent substrate of the window film can be used.
  • the sensing pattern can include a first pattern formed in the first direction and a second pattern formed in the second direction.
  • the first pattern and the second pattern are arranged in different directions from each other.
  • the first pattern and the second pattern are formed in the same layer, and the respective patterns must be electrically connected in order to sense the touched point.
  • the first pattern is a form in which a plurality of unit patterns are connected to each other via a joint, but the second pattern has a structure in which a plurality of unit patterns are separated from each other in an island form, so that the second pattern is electrically operated.
  • a separate bridge electrode is required for the connection.
  • a well-known transparent electrode can be applied to the electrode for connecting the second pattern.
  • Examples of the material of the transparent electrode include indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc oxide (IZTO), and indium gallium zinc oxide (IGZO). , Cadmium tin oxide (CTO), PEDOT (poly (3,4-ethylenedioxythiophene)), carbon nanotubes (CNT), graphene, metal wire and the like, preferably ITO. These can be used alone or in combination of two or more.
  • the metal used for the metal wire is not particularly limited, and examples thereof include silver, gold, aluminum, copper, iron, nickel, titanium, selenium, and chromium, and these may be used alone or in combination of two or more. Can be done.
  • the bridge electrode can be formed on the upper part of the insulating layer via the insulating layer on the upper part of the sensing pattern, the bridge electrode is formed on the substrate, and the insulating layer and the sensing pattern can be formed on the bridge electrode.
  • the bridge electrode may be formed of the same material as the sensing pattern, or may be formed of molybdenum, silver, aluminum, copper, palladium, gold, platinum, zinc, tin, titanium or two or more alloys thereof. it can. Since the first pattern and the second pattern must be electrically insulated, an insulating layer is formed between the sensing pattern and the bridge electrode.
  • the insulating layer may be formed only between the joint of the first pattern and the bridge electrode, or may be formed as a layer covering the entire sensing pattern. In the case of a layer covering the entire sensing pattern, the bridge electrode can connect the second pattern through a contact hole formed in the insulating layer.
  • the touch sensor is induced by a difference in transmittance between a pattern region in which a sensing pattern is formed and a non-pattern region in which a sensing pattern is not formed, specifically, a difference in refractive index in these regions.
  • An optical adjustment layer may be further included between the substrate and the electrode as a means for appropriately compensating for the difference in light transmittance.
  • the optical control layer may contain an inorganic insulating material or an organic insulating material.
  • the optical control layer can be formed by coating a photocurable composition containing a photocurable organic binder and a solvent on a substrate.
  • the photocurable composition may further contain inorganic particles.
  • the refractive index of the optical control layer can be increased by the inorganic particles.
  • the photocurable organic binder contains a copolymer of each monomer such as an acrylate-based monomer, a styrene-based monomer, and a carboxylic acid-based monomer, as long as the effects of the present invention are not impaired. be able to.
  • the photocurable organic binder may be, for example, a copolymer containing different repeating units such as an epoxy group-containing repeating unit, an acrylate repeating unit, and a carboxylic acid repeating unit. Examples of the inorganic particles include zirconia particles, titania particles, alumina particles and the like.
  • the photocuring composition may further contain additives such as a photopolymerization initiator, a polymerizable monomer, and a curing aid.
  • Adhesive layer Each layer of the window film, circularly polarizing plate, touch sensor, etc., which forms the laminated body for the flexible display device, and the film members such as the linear polarizing plate, ⁇ / 4 retardation plate, etc., which form each layer, are joined by an adhesive. Can be done.
  • the adhesive include water-based adhesives, organic solvent-based adhesives, solvent-free adhesives, solid adhesives, solvent volatilization adhesives, water-based solvent volatilization adhesives, moisture-curable adhesives, heat-curable adhesives, and anaerobic adhesives.
  • the thickness of the adhesive layer can be appropriately adjusted according to the required adhesive force and the like, and is preferably 0.01 to 500 ⁇ m, more preferably 0.1 to 300 ⁇ m.
  • the laminated body for a flexible display device has a plurality of adhesive layers, and the thickness and type of each may be the same or different.
  • a polyvinyl alcohol-based polymer a water-soluble polymer such as starch, an ethylene-vinyl acetate-based emulsion, a styrene-butadiene-based emulsion, or the like in an aqueous-dispersed state can be used as the main polymer.
  • a cross-linking agent a silane compound, an ionic compound, a cross-linking catalyst, an antioxidant, a dye, a pigment, an inorganic filler, an organic solvent and the like may be blended.
  • the water-based solvent volatilization type adhesive When adhering with the water-based solvent volatilization type adhesive, the water-based solvent volatilization type adhesive can be injected between the layers to be adhered, the adherend layers are bonded, and then dried to impart adhesiveness.
  • the thickness of the adhesive layer is preferably 0.01 to 10 ⁇ m, more preferably 0.1 to 1 ⁇ m.
  • the thickness and type of each layer may be the same or different.
  • the active energy ray-curable adhesive can be formed by curing an active energy ray-curable composition containing a reactive material that is irradiated with active energy rays to form an adhesive layer.
  • the active energy ray-curable composition can contain at least one polymer of a radical-polymerizable compound and a cationically polymerizable compound similar to those contained in the hard coat composition.
  • the radically polymerizable compound the same compound as the radically polymerizable compound in the hard coat composition can be used.
  • the cationically polymerizable compound the same compound as the cationically polymerizable compound in the hard coat composition can be used.
  • an epoxy compound is preferable. It is also preferable to include a monofunctional compound as a reactive diluent in order to reduce the viscosity of the adhesive composition.
  • the active energy ray composition can contain a monofunctional compound in order to reduce the viscosity.
  • the monofunctional compound include an acrylate-based monomer having one (meth) acryloyl group in one molecule, and a compound having one epoxy group or oxetanyl group in one molecule, for example, glycidyl (meth). ) Examples include acrylate.
  • the active energy ray composition can further contain a polymerization initiator. Examples of the polymerization initiator include radical polymerization initiators, cationic polymerization initiators, radicals and cationic polymerization initiators, and these are appropriately selected and used.
  • These polymerization initiators are decomposed by at least one of active energy ray irradiation and heating to generate radicals or cations to promote radical polymerization and cation polymerization.
  • an initiator that can initiate at least one of radical polymerization or cationic polymerization by irradiation with active energy rays can be used.
  • the active energy ray-curing composition further comprises an ion trapping agent, an antioxidant, a chain transfer agent, an adhesion imparting agent, a thermoplastic resin, a filler, a fluid viscosity modifier, a plasticizer, a defoaming agent solvent, an additive, and a solvent. Can be included.
  • the active energy ray-curable composition is applied to either or both of the layers to be adhered, and then bonded to each layer. Alternatively, both layers to be adhered can be adhered by irradiating them with active energy rays and curing them.
  • the thickness of the adhesive layer is preferably 0.01 to 20 ⁇ m, more preferably 0.1 to 10 ⁇ m.
  • the thickness and type of the respective layers may be the same or different.
  • the pressure-sensitive adhesive is classified into an acrylic pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, a silicone-based pressure-sensitive adhesive, and the like according to the main polymer, and any of them can be used.
  • the pressure-sensitive adhesive may contain a cross-linking agent, a silane compound, an ionic compound, a cross-linking catalyst, an antioxidant, a tackifier, a plasticizing agent, a dye, a pigment, an inorganic filler and the like.
  • a pressure-sensitive adhesive layer is formed by dissolving and dispersing each component constituting the pressure-sensitive adhesive in a solvent to obtain a pressure-sensitive adhesive composition, applying the pressure-sensitive adhesive composition onto a substrate, and then drying the mixture.
  • the adhesive layer may be directly formed, or a separately formed base material may be transferred. It is also preferable to use a release film to cover the adhesive surface before bonding.
  • the thickness of the adhesive layer is preferably 0.1 to 500 ⁇ m, more preferably 1 to 300 ⁇ m.
  • the thickness and type of the respective layers may be the same or different.
  • the shading pattern can be applied as at least part of the bezel or housing of the flexible display device.
  • the light-shielding pattern hides the wiring arranged at the edge of the flexible display device to make it difficult to see, thereby improving the visibility of the image.
  • the shading pattern may be in the form of a single layer or multiple layers.
  • the color of the light-shielding pattern is not particularly limited, and may be various colors such as black, white, and metallic.
  • the light-shielding pattern can be formed of a pigment for embodying color and a polymer such as an acrylic resin, an ester resin, an epoxy resin, polyurethane, or silicone. They can also be used alone or in mixtures of two or more.
  • the shading pattern can be formed by various methods such as printing, lithography, and inkjet.
  • the thickness of the shading pattern is preferably 1 to 100 ⁇ m, more preferably 2 to 50 ⁇ m. It is also preferable to give a shape such as an inclination in the thickness direction of the light-shielding pattern.
  • Total light transmittance In accordance with JIS K 7105: 1981, the total light transmittance (Tt) of the optical films obtained in Examples and Comparative Examples was measured by a fully automatic direct reading haze computer HGM-2DP manufactured by Suga Test Instruments Co., Ltd. ..
  • ⁇ Elastic modulus> The elastic modulus of the optical film obtained in Examples and Comparative Examples was measured using "Autograph AG-IS" manufactured by Shimadzu Corporation. A film having a width of 10 mm in length and width was produced, a stress-strain curve (SS curve) was measured under the conditions of a distance between chucks of 50 mm and a tensile speed of 10 mm / min, and the elastic modulus was calculated from the inclination.
  • SS curve stress-strain curve
  • ⁇ Thickness of optical film> The thickness of the optical film obtained in Examples and Comparative Examples was measured using an ABS digital indicator (“ID-C112BS” manufactured by Mitutoyo Co., Ltd.).
  • Example 1 Preparation of Polyamide-imide Resin (1)
  • TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.13% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc.
  • 6FDA and TAHMBP were added to the flask in an amount of 20.20 mol% each based on TFMB, and the mixture was stirred at room temperature for 16 hours.
  • TPC was added to 27.27 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added to 27.27 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.06 mol% with respect to TFMB, and the mixture was stirred for 2 hours.
  • diisopropylethylamine, 4-picoline, and acetic anhydride were added to the flask so as to be 60.61 mol%, 60.61 mol%, and 282.83 mol%, respectively, with respect to TFMB, and the mixture was stirred for 30 minutes, and then the internal temperature was adjusted. The temperature was raised to 70 ° C., and the mixture was further stirred for 3 hours to obtain a reaction solution.
  • the obtained reaction solution was cooled to room temperature, the reaction solution was poured into a large amount of methanol in the form of filaments, the precipitated precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 60 ° C. to obtain a polyamide-imide resin (1).
  • the Mw of the obtained polyamide-imide resin (1) was 748,000.
  • DMAc was added to the obtained polyamide-imide resin (1) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (1).
  • the obtained polyamide-imide resin varnish (1) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 45 ⁇ m. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film.
  • the free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (1) having a thickness of 40 ⁇ m.
  • Example 2 [Preparation of Polyamide-imide Resin (2)]
  • TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.08% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc.
  • 6FDA and TAHMBP were added to the flask in an amount of 20.62 mol% each based on TFMB, and the mixture was stirred at room temperature for 16 hours.
  • TPC was added to 27.84 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added to 27.84 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.19 mol% with respect to TFMB, and the mixture was stirred for 2 hours.
  • DMAc was added to the obtained polyamide-imide resin (2) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (2).
  • the obtained polyamide-imide resin varnish (2) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 45 ⁇ m. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film.
  • the free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (2) having a thickness of 40 ⁇ m.
  • Example 3 [Preparation of Polyamide-imide Resin (3)]
  • TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.08% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc.
  • 6FDA and TAHMBP were added to the flask in an amount of 20.62 mol% each based on TFMB, and the mixture was stirred at room temperature for 16 hours.
  • TPC was added to 27.84 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added to 27.84 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.19 mol% with respect to TFMB, and the mixture was stirred for 2 hours.
  • DMAc was added to the obtained polyamide-imide resin (3) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (3).
  • the obtained polyamide-imide resin varnish (3) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 45 ⁇ m. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film.
  • the free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (3) having a thickness of 40 ⁇ m.
  • Example 4 [Preparation of Polyamide-imide Resin (4)]
  • TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.16% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc.
  • TAHMBP was added to the flask so as to be 30.61 mol% with respect to TFMB, and the mixture was stirred at room temperature for 16 hours.
  • TPC was added so as to be 32.14 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added so as to be 32.14 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 7.14 mol% with respect to TFMB, and the mixture was stirred for 2 hours.
  • DMAc was added to the obtained polyamide-imide resin (4) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (4).
  • the obtained polyamide-imide resin varnish (4) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 45 ⁇ m. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film.
  • the free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (4) having a thickness of 40 ⁇ m.
  • Example 5 [Preparation of Polyamide-imide Resin (5)]
  • TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 4.86% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc.
  • TAHMBP was added to the flask so as to be 40.82 mol% with respect to TFMB, and the mixture was stirred at room temperature for 16 hours.
  • TPC was added so as to be 27.55 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added so as to be 27.55 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.12 mol% with respect to TFMB, and the mixture was stirred for 2 hours.
  • DMAc was added to the obtained polyamide-imide resin (5) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (5).
  • the obtained polyamide-imide resin varnish (5) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 45 ⁇ m. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film.
  • the free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (5) having a thickness of 40 ⁇ m.
  • Example 6 [Preparation of Polyamide-imide Resin (6)]
  • TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.29% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc.
  • 6FDA and TAHMBP were added to the flask so as to be 10.20 mol% and 20.41 mol%, respectively, based on TFMB, and the mixture was stirred at room temperature for 16 hours.
  • TPC was added so as to be 32.14 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added so as to be 32.14 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 7.14 mol% with respect to TFMB, and the mixture was stirred for 2 hours.
  • DMAc was added to the obtained polyamide-imide resin (6) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (6).
  • the obtained polyamide-imide resin varnish (6) was coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film was 45 ⁇ m. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film.
  • the free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (6) having a thickness of 40 ⁇ m.
  • TPC was added to 27.14 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added to 27.14 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.03 mol% with respect to TFMB, and the mixture was stirred for 2 hours.
  • DMAc was added to the obtained polyamide-imide resin (7) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (7).
  • the obtained polyamide-imide resin varnish (7) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 55 ⁇ m. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film.
  • the free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (7) having a thickness of 50 ⁇ m.
  • TPC was added to 27.84 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added to 27.84 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.19 mol% with respect to TFMB, and the mixture was stirred for 2 hours.
  • DMAc was added to the obtained polyamide-imide resin (8) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (8).
  • the obtained polyamide-imide resin varnish (8) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 55 ⁇ m. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film.
  • the free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (8) having a thickness of 50 ⁇ m.
  • Table 1 shows the results of measuring the proof stress, total light transmittance, haze, YI value and elastic modulus, and evaluating the folding resistance of the optical films obtained in Examples 1 to 6 and Comparative Examples 1 and 2. It was. In Comparative Example 3, the polyamide-imide resin could not be synthesized because it became insoluble during the synthesis, so that the measurement and evaluation could not be performed.

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Abstract

Provided are: a polyamideimide resin which can provide an optical film having high strength; and said optical film. The polyamideimide resin according to the present invention includes structural units represented by formula (1) and formula (2), and includes a structure, represented by formula (3), as Y in formula (1).

Description

ポリアミドイミド樹脂Polyamide-imide resin
　本発明は、ポリアミドイミド樹脂、及び該ポリアミドイミド樹脂を含む光学フィルムに関する。 The present invention relates to a polyamide-imide resin and an optical film containing the polyamide-imide resin.
　液晶表示装置や有機ＥＬ表示装置等の表示装置は、携帯電話やスマートウォッチといった種々の用途に広く活用されている。このような表示装置の前面板としてガラスが用いられてきたが、ガラスは非常に剛直であり、割れやすいため、フレキシブル表示装置の前面板材料としての利用は難しい。そのため、ガラスに代わる材料として高分子材料の活用が検討されている。高分子材料からなる前面板はフレキシブル特性を発現し易いため、種々の用途に用いることが期待できる。柔軟性を有する樹脂としては種々のものが挙げられるが、その一つにポリイミド系樹脂がある。例えば、特許文献１及び特許文献２には、ポリイミド樹脂やポリアミドイミド樹脂から形成された光学フィルムが記載されている。 Display devices such as liquid crystal display devices and organic EL display devices are widely used in various applications such as mobile phones and smart watches. Glass has been used as the front plate of such a display device, but it is difficult to use it as a front plate material of a flexible display device because the glass is very rigid and easily broken. Therefore, the use of polymer materials as an alternative material to glass is being studied. Since the front plate made of a polymer material easily exhibits flexible properties, it can be expected to be used for various purposes. Various types of flexible resins can be mentioned, and one of them is a polyimide resin. For example, Patent Document 1 and Patent Document 2 describe an optical film formed of a polyimide resin or a polyamide-imide resin.
国際公開第２０１４／０４６１８０号International Publication No. 2014/046180 国際公開第２０１６／１５２４５９号International Publication No. 2016/152459
　フレキシブル表示装置の材料などに使用される光学フィルムには、耐折性等の特徴が要求される。本発明者らは、光学フィルムのこれらの要求性能を高めるために検討を進めたところ、光学フィルムの耐力を高めることによって、耐折性等に優れた光学フィルムが得られることを見出した。 Optical films used as materials for flexible display devices are required to have features such as folding resistance. The present inventors have conducted studies in order to enhance these required performances of the optical film, and have found that an optical film having excellent folding resistance and the like can be obtained by increasing the proof stress of the optical film.
　したがって、本発明は、高耐力を有する光学フィルムを提供し得るポリアミドイミド樹脂、及び該光学フィルムを提供することを目的とする。 Therefore, an object of the present invention is to provide a polyamide-imide resin capable of providing an optical film having a high yield strength, and the optical film.
　本発明者らは、上記課題を解決するために鋭意検討した結果、本発明に到達した。すなわち本発明は、以下の好適な形態を提供するものである。
　［１］式（１）及び式（２）： The present inventors have arrived at the present invention as a result of diligent studies to solve the above problems. That is, the present invention provides the following suitable forms.
[1] Equation (1) and Equation (2):
Figure JPOXMLDOC01-appb-C000006
 ［式（１）及び式（２）中、Ｘ及びＺは、互いに独立に、２価の有機基を表し、Ｙは４価の有機基を表し、＊は結合手を表す］
で表される構成単位を含み、式（１）中のＹとして、式（３）：
Figure JPOXMLDOC01-appb-C000006
 [In formulas (1) and (2), X and Z represent divalent organic groups independently of each other, Y represents a tetravalent organic group, and * represents a bond.]
Including the structural unit represented by, as Y in the formula (1), the formula (3):
Figure JPOXMLDOC01-appb-C000007
 ［式（３）中、Ｒ１は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、Ｒ２～Ｒ５は、互いに独立に、水素原子、又はハロゲン原子を有してもよい１価の炭化水素基を表し、ｍは、互いに独立に、０～３の整数を表し、ｎは１～４の整数を表し、＊は結合手を表し、ただし、Ｒ２～Ｒ５を有する少なくとも１つのベンゼン環において、Ｒ２～Ｒ５の少なくとも１つがハロゲン原子を有してもよい１価の炭化水素基である］
で表される構造を含む、ポリアミドイミド樹脂。
　［２］式（１）及び式（２）中のＸとして、２価の芳香族基、２価の脂環族基、及び２価の脂肪族基の少なくとも１種を含む、前記［１］に記載のポリアミドイミド樹脂。
　［３］式（１）及び式（２）中のＸとして、式（４）：
Figure JPOXMLDOC01-appb-C000007
 [In the formula (3), R 1 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group which may have a halogen atom or a halogen atom independently of each other, and R 2 to R 5 are Independently of each other, they represent a monovalent hydrocarbon group which may have a hydrogen atom or a halogen atom, m represents an integer of 0 to 3 independently of each other, and n represents an integer of 1 to 4. * represents a bonding hand, provided that at least one benzene ring having R 2 ~ R 5, at least one 1 may have a halogen atom monovalent hydrocarbon group R 2 ~ R 5]
Polyamide-imide resin containing the structure represented by.
[2] The above-mentioned [1], wherein X in the formulas (1) and (2) contains at least one of a divalent aromatic group, a divalent alicyclic group, and a divalent aliphatic group. The polyamide-imide resin described in 1.
[3] As X in the equations (1) and (2), the equation (4):
Figure JPOXMLDOC01-appb-C000008
 ［式（４）中、Ａは、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＡ１）－又は－Ｓｉ（ＲＡ２）２－を表し、ＲＡ１及びＲＡ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表し、Ｒ６は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、ｓは、互いに独立に、０～４の整数を表し、＊は結合手を表す］
で表される構造を含む、前記［１］又は［２］に記載のポリアミドイミド樹脂。
　［４］式（１）中のＹとして、式（５）：
Figure JPOXMLDOC01-appb-C000008
 [In formula (4), A is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-,-. PO -, - PO 2 -, - N (R A1) - , or -Si (R A2) 2 - represents, R A1 and R A2 are, independently of one another, may have a hydrogen atom, or a halogen atom Representing an alkyl group, R 6 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, which may have a halogen atom or a halogen atom independently of each other, and s represents 0 to independently of each other. Represents an integer of 4, * represents a bond]
The polyamide-imide resin according to the above [1] or [2], which comprises the structure represented by.
[4] As Y in the equation (1), the equation (5):
Figure JPOXMLDOC01-appb-C000009
 ［式（５）中、Ｂは、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＣＯＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＢ１）－又は－Ｓｉ（ＲＢ２）２－を表し、ＲＢ１及びＲＢ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表し、Ｒ７は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、ｔは、互いに独立に、０～３の整数を表し、＊は結合手を表す］
で表される構造をさらに含む、前記［１］～［３］のいずれかに記載のポリアミドイミド樹脂。
　［５］式（２）中のＺとして、式（６）：
Figure JPOXMLDOC01-appb-C000009
 [In formula (5), B is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-,-. It represents COO-, -PO-, -PO 2- , -N ( RB1 )-or-Si ( RB2 ) 2- , and RB1 and RB2 have hydrogen atoms or halogen atoms independently of each other. Represents an alkyl group which may have an alkyl group, R 7 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group which may have a halogen atom and a halogen atom independently of each other, and t represents an alkyl group which may have a halogen atom and a halogen atom. Represents an integer from 0 to 3, and * represents a bond]
The polyamide-imide resin according to any one of [1] to [3] above, further comprising the structure represented by.
[5] As Z in the equation (2), the equation (6):
Figure JPOXMLDOC01-appb-C000010
 ［式（６）中、Ｗは、互いに独立に、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＣ１）－又は－Ｓｉ（ＲＣ２）２－を表し、ＲＣ１及びＲＣ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表し、Ｒ８は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、ｐは、互いに独立に、０～４の整数を表し、ｑは０～４の整数を表し、＊は結合手を表す］
で表される構造を含む、前記［１］～［４］のいずれかに記載のポリアミドイミド樹脂。
　［６］重量平均分子量は１００，０００以上である、前記［１］～［５］のいずれかに記載のポリアミドイミド樹脂。
　［７］前記［１］～［６］のいずれかに記載のポリアミドイミド樹脂を含む、光学フィルム。
　［８］黄色度は３．０未満である、前記［７］に記載の光学フィルム。
　［９］全光線透過率は９０％以上である、前記［７］又は［８］に記載の光学フィルム。
　［１０］弾性率は５．０ＧＰａ以上である、前記［７］～［９］のいずれかに記載の光学フィルム。
　［１１］フレキシブル表示装置の前面板用フィルムである、前記［７］～［１０］のいずれかに記載の光学フィルム。
　［１２］前記［７］～［１１］のいずれかに記載の光学フィルムを備える、フレキシブル表示装置。
　［１３］タッチセンサをさらに備える、前記［１２］に記載のフレキシブル表示装置。
　［１４］偏光板をさらに備える、前記［１２］又は［１３］に記載のフレキシブル表示装置。
Figure JPOXMLDOC01-appb-C000010
 Wherein (6), W, independently of one another, a single bond, -O-, diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2 -, - S - , - It represents CO-, -PO-, -PO 2- , -N ( RC1 )-or-Si ( RC2 ) 2- , and RC1 and RC2 have hydrogen atom or halogen atom independently of each other. R 8 represents an alkyl group which may have a halogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, and p is independent of each other. , 0 to 4 represents an integer, q represents an integer from 0 to 4, and * represents a bond.]
The polyamide-imide resin according to any one of [1] to [4] above, which comprises the structure represented by.
[6] The polyamide-imide resin according to any one of [1] to [5] above, wherein the weight average molecular weight is 100,000 or more.
[7] An optical film containing the polyamide-imide resin according to any one of the above [1] to [6].
[8] The optical film according to the above [7], which has a yellowness of less than 3.0.
[9] The optical film according to the above [7] or [8], wherein the total light transmittance is 90% or more.
[10] The optical film according to any one of [7] to [9] above, which has an elastic modulus of 5.0 GPa or more.
[11] The optical film according to any one of [7] to [10] above, which is a film for a front plate of a flexible display device.
[12] A flexible display device including the optical film according to any one of the above [7] to [11].
[13] The flexible display device according to the above [12], further comprising a touch sensor.
[14] The flexible display device according to the above [12] or [13], further comprising a polarizing plate.
　本発明によれば、高耐力を有する光学フィルムを提供し得るポリアミドイミド樹脂、及び該光学フィルムを提供できる。 According to the present invention, it is possible to provide a polyamide-imide resin that can provide an optical film having high yield strength, and the optical film.
　〔ポリアミドイミド樹脂〕
　本発明のポリアミドイミド樹脂は、式（１）及び式（２）： [Polyamide-imide resin]
The polyamide-imide resin of the present invention has the formulas (1) and (2):
Figure JPOXMLDOC01-appb-C000011
 ［式（１）及び式（２）中、Ｘ及びＺは、互いに独立に、２価の有機基を表し、Ｙは４価の有機基を表し、＊は結合手を表す］
で表される構成単位を含む。
Figure JPOXMLDOC01-appb-C000011
 [In formulas (1) and (2), X and Z represent divalent organic groups independently of each other, Y represents a tetravalent organic group, and * represents a bond.]
Includes the building blocks represented by.
　式（１）中、Ｙは、互いに独立に、４価の有機基を表し、好ましくは炭素数４～８０の４価の有機基、より好ましくは環状構造を有する炭素数４～６０の４価の有機基を表す。環状構造としては、脂環、芳香環、ヘテロ環構造が挙げられる。前記有機基は、置換基を有してもよい有機基であり、該置換基は、好ましくはハロゲン原子、ハロゲン原子を有してもよい、１価の炭化水素基（例えばアルキル基、アリール基等）、アルコキシ基又はアリールオキシ基である。本発明の一実施形態であるポリアミドイミド樹脂は、複数種のＹを含み得、複数種のＹは、互いに同一であっても異なっていてもよい。 In the formula (1), Y represents a tetravalent organic group independently of each other, preferably a tetravalent organic group having 4 to 80 carbon atoms, and more preferably a tetravalent organic group having a cyclic structure and having 4 to 60 carbon atoms. Represents an organic group of. Examples of the cyclic structure include an alicyclic ring, an aromatic ring, and a heterocyclic structure. The organic group is an organic group which may have a substituent, and the substituent may preferably have a halogen atom or a halogen atom, and is a monovalent hydrocarbon group (for example, an alkyl group or an aryl group). Etc.), alkoxy group or aryloxy group. The polyamide-imide resin according to the embodiment of the present invention may contain a plurality of types of Y, and the plurality of types of Y may be the same as or different from each other.
　また、本発明のポリアミドイミド樹脂は、式（１）中のＹとして、式（３）： Further, the polyamide-imide resin of the present invention has a formula (3): as Y in the formula (1).
Figure JPOXMLDOC01-appb-C000012
 ［式（３）中、Ｒ１は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、Ｒ２～Ｒ５は、互いに独立に、水素原子、又はハロゲン原子を有してもよい１価の炭化水素基を表し、ｍは、互いに独立に、０～３の整数を表し、ｎは１～４の整数を表し、＊は結合手を表し、ただし、Ｒ２～Ｒ５を有する少なくとも１つのベンゼン環において、Ｒ２～Ｒ５の少なくとも１つがハロゲン原子を有してもよい１価の炭化水素基である］
で表される構造を少なくとも含む。
Figure JPOXMLDOC01-appb-C000012
 [In the formula (3), R 1 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group which may have a halogen atom or a halogen atom independently of each other, and R 2 to R 5 are Independently of each other, they represent a monovalent hydrocarbon group which may have a hydrogen atom or a halogen atom, m represents an integer of 0 to 3 independently of each other, and n represents an integer of 1 to 4. * represents a bonding hand, provided that at least one benzene ring having R 2 ~ R 5, at least one 1 may have a halogen atom monovalent hydrocarbon group R 2 ~ R 5]
Including at least the structure represented by.
　本発明者らは、式（１）及び式（２）で表される構造単位を含むポリアミドイミド樹脂において、式（１）中のＹが式（３）で表される構造を少なくとも含む場合、該ポリアミドイミド樹脂を含む光学フィルムの耐力が向上することを見出した。ポリアミドイミド樹脂が式（１）中のＹとして、式（３）で表される構造を含むことにより、該光学フィルムの耐力を高めやすい理由は明らかではないが、式（３）で表される構造は剛直でありながら側鎖を有するため、分子間パッキングを阻害する構造であり、かかる構造を含むことにより、ポリアミドイミド樹脂が高弾性率となりながら高靭性となり、より降伏に至るまでの応力が向上するためであると考えられる。また、このような構造を含むため、本発明のポリアミドイミド樹脂は、光学特性にも優れており、高耐力及び優れた光学特性を両立できる。 In the polyamide-imide resin containing the structural units represented by the formulas (1) and (2), the present inventors consider that Y in the formula (1) contains at least the structure represented by the formula (3). It has been found that the proof stress of the optical film containing the polyamide-imide resin is improved. Although it is not clear why the polyamide-imide resin is likely to increase the proof stress of the optical film by including the structure represented by the formula (3) as Y in the formula (1), it is represented by the formula (3). Since the structure is rigid but has side chains, it is a structure that hinders intermolecular packing. By including such a structure, the polyamide-imide resin has a high elastic modulus and high toughness, and the stress until yielding is further increased. It is thought that this is to improve. Further, since the polyamide-imide resin of the present invention contains such a structure, it has excellent optical properties, and can achieve both high yield strength and excellent optical properties.
　式（３）中、Ｒ１は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表す。ハロゲン原子としては、例えばフッ素原子、塩素原子、臭素原子、ヨウ素原子が挙げられる。アルキル基としては、例えばメチル基、エチル基、ｎ－プロピル基、イソプロピル基、ｎ－ブチル基、ｓｅｃ－ブチル基、ｔｅｒｔ－ブチル基、ｎ－ペンチル基、２－メチル－ブチル基、３－メチルブチル基、２－エチル－プロピル基、ｎ－ヘキシル基などが挙げられる。アルコキシ基としては、例えばメトキシ基、エトキシ基、プロピルオキシ基、イソプロピルオキシ基、ブトキシ基、イソブトキシ基、ｔｅｒｔ－ブトキシ基、ペンチルオキシ基、ヘキシルオキシ基、シクロヘキシルオキシ基などが挙げられる。アリール基としては、例えばフェニル基、トリル基、キシリル基、ナフチル基、ビフェニル基などが挙げられる。アリールオキシ基としては、例えばフェノキシ基、ナフチルオキシ基、ビフェニルオキシ基などが挙げられる。Ｒ１は、互いに独立に、好ましくは、ハロゲン原子、ハロゲン原子を有してもよい、炭素数１～６のアルキル基、炭素数１～６のアルコキシ基、炭素数６～１２のアリール基、又は炭素数６～１２のアリールオキシ基を表す。 In formula (3), R 1 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, which may have a halogen atom or a halogen atom independently of each other. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, 2-methyl-butyl group and 3-methylbutyl group. Groups, 2-ethyl-propyl groups, n-hexyl groups and the like can be mentioned. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propyloxy group, an isopropyloxy group, a butoxy group, an isobutoxy group, a tert-butoxy group, a pentyloxy group, a hexyloxy group, a cyclohexyloxy group and the like. Examples of the aryl group include a phenyl group, a tolyl group, a xsilyl group, a naphthyl group, a biphenyl group and the like. Examples of the aryloxy group include a phenoxy group, a naphthyloxy group, a biphenyloxy group and the like. R 1 is independent of each other, preferably having a halogen atom or a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, and the like. Alternatively, it represents an aryloxy group having 6 to 12 carbon atoms.
　式（３）中、ポリアミドイミド樹脂を含む光学フィルム（以下、単に光学フィルムという場合がある）の弾性率及び透明性を向上しやすく、かつ、耐力を向上しやすい観点から、ｍは、互いに独立に、０～３の整数を表し、好ましくは０～２の整数、より好ましくは０又は１、さらに好ましくは０を表す。 In the formula (3), m is independent of each other from the viewpoint of easily improving the elasticity and transparency of the optical film containing the polyamide-imide resin (hereinafter, may be simply referred to as the optical film) and improving the resistance. In addition, it represents an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 0.
　式（３）中、Ｒ２、Ｒ３、Ｒ４及びＲ５は、互いに独立に、水素原子、又はハロゲン原子を有してもよい１価の炭化水素基を表す。１価の炭化水素基としては、芳香族炭化水素基、脂環族炭化水素基、脂肪族炭化水素基が挙げられる。芳香族炭化水素基としては、例えばフェニル基、トリル基、キシリル基、ナフチル基、ビフェニル基などのアリール基などが挙げられる。脂環族炭化水素基としては、シクロペンチル基、シクロヘキシル基等のシクロアルキル基などが挙げられる。脂肪族炭化水素基としては、例えばメチル基、エチル基、ｎ－プロピル基、イソプロピル基、ｎ－ブチル基、ｓｅｃ－ブチル基、ｔｅｒｔ－ブチル基、ｎ－ペンチル基、２－メチル－ブチル基、３－メチルブチル基、２－エチル－プロピル基、ｎ－ヘキシル、ｎ－ヘプチル基、ｎ－オクチル基、ｔｅｒｔ－オクチル基、ｎ－ノニル基、ｎ－デシル基等のアルキル基などが挙げられる。ハロゲン原子としては、上記に記載のものが挙げられる。Ｒ２～Ｒ５は、互いに独立に、好ましくは水素原子、又はハロゲン原子を有してもよい、炭素数６～１２のアリール基、炭素数４～８のシクロアルキル基、又は炭素数１～６のアルキル基を表す。樹脂の溶媒への溶解性並びに光学フィルムの弾性率及び透明性を向上しやすく、かつ、光学フィルムの耐力を向上しやすい観点から、Ｒ２～Ｒ５は、互いに独立に、好ましくは水素原子、又はハロゲン原子を有してもよいアルキル基、より好ましくは水素原子、又はハロゲン原子を有してもよい１～６のアルキル基、さらに好ましくは水素原子、又はハロゲン原子を有してもよい１～３のアルキル基を表す。 In formula (3), R 2 , R 3 , R 4 and R 5 represent monovalent hydrocarbon groups that may have hydrogen or halogen atoms independently of each other. Examples of the monovalent hydrocarbon group include an aromatic hydrocarbon group, an alicyclic hydrocarbon group, and an aliphatic hydrocarbon group. Examples of the aromatic hydrocarbon group include an aryl group such as a phenyl group, a tolyl group, a xsilyl group, a naphthyl group and a biphenyl group. Examples of the alicyclic hydrocarbon group include a cycloalkyl group such as a cyclopentyl group and a cyclohexyl group. Examples of the aliphatic hydrocarbon group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group and a 2-methyl-butyl group. Examples thereof include alkyl groups such as 3-methylbutyl group, 2-ethyl-propyl group, n-hexyl, n-heptyl group, n-octyl group, tert-octyl group, n-nonyl group and n-decyl group. Examples of the halogen atom include those described above. R 2 - R 5 are, independently of one another, preferably a hydrogen atom, or a halogen atom may have an aryl group having 6 to 12 carbon atoms, a cycloalkyl group having 4 to 8 carbon atoms, or C 1 -C Represents an alkyl group of 6. Easily improved elastic modulus and transparency of the solubility and the optical film of the resin to the solvent and yield strength from the viewpoint of easily improving the optical film, R 2 ~ R 5 independently of one another, preferably a hydrogen atom, Alternatively, it may have an alkyl group which may have a halogen atom, more preferably a hydrogen atom, or 1 to 6 alkyl groups which may have a halogen atom, and more preferably a hydrogen atom or a halogen atom1. Represents ~ 3 alkyl groups.
　式（３）中、Ｒ２～Ｒ５を有する少なくとも１つのベンゼン環において、Ｒ２～Ｒ５の少なくとも１つがハロゲン原子を有してもよい１価の炭化水素基である。式（３）中のＲ２～Ｒ５を有する全てのベンゼン環において、Ｒ２～Ｒ５のうち、ハロゲン原子を有してもよい１価の炭化水素基が１つ未満であると、光学フィルムの耐力を十分に向上しにくく、光学特性も低下しやすい。式（３）において、光学フィルムの耐力を向上しやすく、かつ、光学特性を高めやすい観点から、Ｒ２～Ｒ５を有する少なくとも１つのベンゼン環において、Ｒ２～Ｒ５のうちの好ましくは２～４つ、より好ましくは３又は４つ、さらに好ましくは３つが、ハロゲン原子を有してもよい１価の炭化水素基である。 In the formula (3), at least one benzene ring having R 2 ~ R 5, at least one 1 may have a halogen atom monovalent hydrocarbon group R 2 ~ R 5. In all of the benzene ring having R 2 ~ R 5 in formula (3), of the R 2 ~ R 5, when the monovalent hydrocarbon group which may have a halogen atom is fewer than one optical It is difficult to sufficiently improve the yield strength of the film, and the optical characteristics are likely to deteriorate. In the formula (3), from the viewpoint of easily improving the proof stress of the optical film and easily improving the optical characteristics, preferably 2 of R 2 to R 5 is used in at least one benzene ring having R 2 to R 5. ~ 4, more preferably 3 or 4, still more preferably 3 are monovalent hydrocarbon groups which may have halogen atoms.
　樹脂の溶媒への溶解性並びに光学フィルムの耐力、破断歪、弾性率及び透明性をより向上しやすい観点から、ｎが２以上の場合、Ｒ２～Ｒ５を有する少なくとも２つのベンゼン環において、Ｒ２～Ｒ５の少なくとも１つがハロゲン原子を有してもよい１価の炭化水素基であることがより好ましく、Ｒ２～Ｒ５を有する全てのベンゼン環において、Ｒ２～Ｒ５の少なくとも１つがハロゲン原子を有してもよい１価の炭化水素基であることがさらに好ましい。 Strength of solubility and optical film of the resin to the solvent, fracture strain, from a more easily improved in view of elasticity and transparency, when n is 2 or more, at least two benzene rings having R 2 ~ R 5, more preferably at least one of R 2 ~ R 5 is a monovalent hydrocarbon group which may have a halogen atom, in all the benzene ring having R 2 ~ R 5, at least R 2 ~ R 5 It is more preferable that one is a monovalent hydrocarbon group which may have a halogen atom.
　式（３）中、ｎは１～４の整数を表し、光学フィルムの耐力、弾性率及び透明性を向上しやすい観点から、ｎは好ましくは１～３の整数、より好ましくは２又は３、さらに好ましくは２である。なお、式（１）で表される構成単位は、Ｙとして、式（３）で表される構造（又は基）を１種又は複数種含んでいてよい。 In the formula (3), n represents an integer of 1 to 4, and n is preferably an integer of 1 to 3, more preferably 2 or 3, from the viewpoint of easily improving the strength, elastic modulus and transparency of the optical film. More preferably, it is 2. The structural unit represented by the formula (1) may include one or more types of structures (or groups) represented by the formula (3) as Y.
　本発明の好適な実施形態においては、式（３）は、式（３’）： In a preferred embodiment of the present invention, the formula (3) is the formula (3'):
Figure JPOXMLDOC01-appb-C000013
 ［式（３’）中、＊は結合手を表す］
で表される。すなわち、本発明の好適な実施形態において、ポリアミドイミド樹脂は、式（１）中のＹとして、式（３’）で表される構造を含む。このような形態であると、光学フィルムの耐力、弾性率及び透明性を向上しやすい。
Figure JPOXMLDOC01-appb-C000013
 [In equation (3'), * represents a bond]
It is represented by. That is, in a preferred embodiment of the present invention, the polyamide-imide resin contains a structure represented by the formula (3') as Y in the formula (1). With such a form, it is easy to improve the proof stress, elastic modulus and transparency of the optical film.
　本発明の一実施形態では、式（１）で表される構成単位のうち、Ｙが式（３）で表される構造である構成単位の割合は、式（１）で表される構成単位の総モル量（１００モル％）に対して、好ましくは３０モル％以上、より好ましくは３５モル％以上、さらに好ましくは４０モル％以上であり、好ましくは１００モル％以下、より好ましくは９０モル％以下、さらに好ましくは８０モル％以下、とりわけ好ましくは７０モル％以下である。Ｙが式（３）で表される構成単位の割合が上記の下限値以上であると、光学フィルムの耐力及び弾性率を向上しやすい。また、上記の上限値以下であると、光学フィルムの破断歪及び透明性を高めやすい。Ｙが式（３）で表される構成単位の割合は、例えば１Ｈ－ＮＭＲを用いて測定することができ、又は原料の仕込み比から算出することもできる。 In one embodiment of the present invention, among the structural units represented by the formula (1), the proportion of the structural units having a structure in which Y is represented by the formula (3) is the structural unit represented by the formula (1). 30 mol% or more, more preferably 35 mol% or more, still more preferably 40 mol% or more, preferably 100 mol% or less, more preferably 90 mol, based on the total molar amount (100 mol%) of % Or less, more preferably 80 mol% or less, and particularly preferably 70 mol% or less. When the proportion of the structural unit in which Y is represented by the formula (3) is at least the above lower limit value, the proof stress and elastic modulus of the optical film can be easily improved. Further, when it is not more than the above upper limit value, it is easy to increase the breaking strain and transparency of the optical film. The ratio of the structural unit in which Y is represented by the formula (3) can be measured using, for example, 1 1 H-NMR, or can be calculated from the charging ratio of raw materials.
　本発明のポリアミドイミド樹脂は、式（１）中のＹとして、さらに式（２０）、式（２１）、式（２２）、式（２３）、式（２４）、式（２５）、式（２６）、式（２７）、式（２８）及び式（２９）： The polyamide-imide resin of the present invention has the formula (20), the formula (21), the formula (22), the formula (23), the formula (24), the formula (25), and the formula (25) as Y in the formula (1). 26), Eq. (27), Eq. (28) and Eq. (29):
Figure JPOXMLDOC01-appb-C000014
 で表される構造を含んでもよい。
Figure JPOXMLDOC01-appb-C000014
 It may include the structure represented by.
　式（２０）～式（２９）中、＊は結合手を表し、Ｗ１は、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基（例えば－ＣＨ２－、－ＣＨ２－ＣＨ２－、－ＣＨ（ＣＨ３）－、－Ｃ（ＣＨ３）２－、－Ｃ（ＣＦ３）２－）、－Ａｒ－、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＷ１）－又は－Ｓｉ（ＲＷ２）２－、－Ｏ－Ａｒ－Ｏ－、－Ａｒ－Ｏ－Ａｒ－、－Ａｒ－ＣＨ２－Ａｒ－、－Ａｒ－Ｃ（ＣＨ３）２－Ａｒ－又は－Ａｒ－ＳＯ２－Ａｒ－を表す。Ａｒは、フッ素原子を有してもよい炭素数６～２０のアリーレン基を表し、具体例としてはフェニレン基が挙げられる。ＲＷ１及びＲＷ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表す。なお、式（２０）～式（２９）で表される基中の水素原子は、メチル基、フルオロ基、クロロ基又はトリフルオロメチル基で置換された基；並びに４価の炭素数６以下の鎖式炭化水素基であってよい。なお、式（２０）～式（２９）における環上の水素原子は、炭素数１～６のアルキル基、炭素数１～６のアルコキシ基又は炭素数６～１２のアリール基で置換されていてもよい。炭素数１～６のアルキル基、炭素数１～６のアルコキシ基及び炭素数６～１２のアリール基としては、それぞれ、式（３）のＲ１として例示されたものが挙げられる。 In formulas (20) to (29), * represents a bond, W 1 is a single bond, —O—, a diphenylmethylene group, and a divalent hydrocarbon group (eg, −” which may have a halogen atom. CH 2- , -CH 2- CH 2-, -CH (CH 3 )-, -C (CH 3 ) 2- , -C (CF 3 ) 2- ), -Ar-, -SO 2- , -S -, -CO-, -PO-, -PO 2- , -N ( RW1 )-or-Si ( RW2 ) 2- , -O-Ar-O-, -Ar-O-Ar-, -Ar Represents -CH 2 -Ar-, -Ar-C (CH 3 ) 2- Ar- or -Ar-SO 2- Ar-. Ar represents an arylene group having 6 to 20 carbon atoms which may have a fluorine atom, and specific examples thereof include a phenylene group. RW1 and RW2 represent alkyl groups which may have a hydrogen atom or a halogen atom independently of each other. The hydrogen atom in the group represented by the formulas (20) to (29) is a group substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; and a tetravalent group having 6 or less carbon atoms. It may be a chain hydrocarbon group. The hydrogen atom on the ring in the formulas (20) to (29) is substituted with an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms. May be good. Examples of the alkyl group having 1 to 6 carbon atoms, the alkoxy group having 1 to 6 carbon atoms, and the aryl group having 6 to 12 carbon atoms include those exemplified as R 1 of the formula (3), respectively.
　式（２０）～式（２９）で表される基の中でも、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、式（２６）、式（２８）又は式（２９）で表される基が好ましく、式（２６）で表される基がより好ましい。また、Ｗ１は、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、好ましくは単結合、－Ｏ－、－ＣＨ２－、－ＣＨ２－ＣＨ２－、－ＣＨ（ＣＨ３）－、－Ｃ（ＣＨ３）２－又は－Ｃ（ＣＦ３）２－、より好ましくは単結合、－Ｏ－、－ＣＨ２－、－ＣＨ（ＣＨ３）－、－Ｃ（ＣＨ３）２－又は－Ｃ（ＣＦ３）２－、さらに好ましくは単結合、－Ｃ（ＣＨ３）２－又は－Ｃ（ＣＦ３）２－、さらにより好ましくは単結合又は－Ｃ（ＣＦ３）２－、とりわけ好ましくは－Ｃ（ＣＦ３）２－を表す。 Among the groups represented by the formulas (20) to (29), the formula (26), the formula (28) or the formula (29) from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film. ) Is preferable, and the group represented by the formula (26) is more preferable. Further, W 1 is yield strength of the optical film, fracture strain, from the viewpoint of easily improving the elastic modulus and transparency, preferably a single bond, -O -, - CH 2 - , - CH 2 -CH 2 -, - CH (CH 3 )-, -C (CH 3 ) 2 -or-C (CF 3 ) 2- , more preferably single bond, -O-, -CH 2- , -CH (CH 3 )-, -C ( CH 3 ) 2- or -C (CF 3 ) 2- , more preferably single bond, -C (CH 3 ) 2- or -C (CF 3 ) 2- , even more preferably single bond or -C (CF) 3) 2 -, particularly preferably -C (CF 3) 2 - represents a.
　本発明の好適な実施形態において、式（２６）は、式（５）： In a preferred embodiment of the present invention, the formula (26) is the formula (5) :.
Figure JPOXMLDOC01-appb-C000015
 ［式（５）中、Ｂは、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＣＯＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＢ１）－又は－Ｓｉ（ＲＢ２）２－を表し、ＲＢ１及びＲＢ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表し、Ｒ７は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、ｔは、互いに独立に、０～３の整数を表し、＊は結合手を表す］
で表される。ポリアミドイミド樹脂が、式（１）中のＹとして、式（５）で表される構造をさらに含むと、樹脂の溶媒への溶解性、並びに光学フィルムの耐力及び透明性を向上しやすい。
Figure JPOXMLDOC01-appb-C000015
 [In formula (5), B is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-,-. It represents COO-, -PO-, -PO 2- , -N ( RB1 )-or-Si ( RB2 ) 2- , and RB1 and RB2 have hydrogen atoms or halogen atoms independently of each other. Represents an alkyl group which may have an alkyl group, R 7 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group which may have a halogen atom and a halogen atom independently of each other, and t represents an alkyl group which may have a halogen atom and a halogen atom. Represents an integer from 0 to 3, and * represents a bond]
It is represented by. When the polyamide-imide resin further contains the structure represented by the formula (5) as Y in the formula (1), the solubility of the resin in the solvent and the strength and transparency of the optical film are likely to be improved.
　式（５）中、Ｒ７は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表す。ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基及びアリールオキシ基としては、それぞれ式（３）のＲ１として上記に例示のものが挙げられる。光学フィルムの破断歪、弾性率及び透明性を向上しやすい観点から、Ｒ７は、互いに独立に、好ましくはハロゲン原子を有してもよい炭素数１～６のアルキル基であり、より好ましくはハロゲン原子を有してもよい炭素数１～３のアルキル基である。 In formula (5), R 7 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, which may have a halogen atom or a halogen atom independently of each other. Halogen atom, may have a halogen atom, an alkyl group, an alkoxy group, the aryl group and aryloxy group, exemplified above are mentioned as R 1 in each formula (3). From the viewpoint of easily improving the breaking strain, elastic modulus and transparency of the optical film, R 7 is an alkyl group having 1 to 6 carbon atoms which may have a halogen atom independently of each other, and more preferably. It is an alkyl group having 1 to 3 carbon atoms which may have a halogen atom.
　式（５）中、ｔは、互いに独立に、０～３の整数を表し、光学フィルムの破断歪、弾性率及び透明性を向上しやすい観点から、好ましくは０～２の整数を表し、より好ましくは０又は１を表し、さらに好ましくは０である。 In the formula (5), t represents an integer of 0 to 3 independently of each other, and preferably represents an integer of 0 to 2 from the viewpoint of easily improving the breaking strain, elastic modulus and transparency of the optical film. It preferably represents 0 or 1, and more preferably 0.
　式（５）中、Ｂは、互いに独立に、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＣＯＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＢ１）－又は－Ｓｉ（ＲＢ２）２－を表し、ＲＢ１及びＲＢ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表す。 In formula (5), B is a divalent hydrocarbon group which may have a single bond, —O—, a diphenylmethylene group, and a halogen atom independently of each other, —SO 2-, —S—, —CO. -, -COO-, -PO-, -PO 2- , -N ( RB1 )-or-Si ( RB2 ) 2- represents, and RB1 and RB2 are independent of each other, hydrogen atom or halogen. Represents an alkyl group that may have an atom.
　ハロゲン原子を有してもよい２価の炭化水素基としては、式（３）中のＲ２～Ｒ５におけるハロゲン原子を有してもよい１価の炭化水素基のうち、水素原子をさらに１つ除いた２価の基が挙げられる。ハロゲン原子を有してもよい２価の炭化水素基は、その基に含まれる水素原子のうち、２つの水素原子に代わって環を形成、すなわち、該２つの水素原子を結合手に代え、その２つの結合手を連結させて環を形成してもよく、該環としては、例えば炭素数３～１２のシクロアルカン環などが挙げられる。また、式（５）中のＢに含まれる－Ｎ（ＲＢ１）－及び－Ｓｉ（ＲＢ２）２－中のＲＢ１及びＲＢ２におけるハロゲン原子を有してもよいアルキル基としては、式（３）中のＲ１におけるハロゲン原子を有してもよいアルキル基として上記に例示のものが挙げられる。 Examples of the divalent hydrocarbon group which may have a halogen atom, the formula (3) in the R 2 ~ of monovalent hydrocarbon group which may have a halogen atom in R 5, further hydrogen atom A divalent group excluding one can be mentioned. A divalent hydrocarbon group, which may have a halogen atom, forms a ring in place of two hydrogen atoms among the hydrogen atoms contained in the group, that is, the two hydrogen atoms are replaced by a bonder. The two bonds may be connected to form a ring, and examples of the ring include a cycloalcan ring having 3 to 12 carbon atoms. Also, -N contained B in formula (5) (R B1) - and -Si (R B2) 2 - Examples of the alkyl group which may have a halogen atom in R B1 and R B2 medium, wherein Examples of the alkyl group which may have a halogen atom in R 1 in (3) are mentioned above.
　式（５）中、Ｂは、光学フィルムの透明性、弾性率及び耐屈曲性を向上しやすい観点から、好ましくは単結合、又は、ハロゲン原子を有してもよい２価の炭化水素基、より好ましくは単結合、－ＣＨ２－、－ＣＨ２－ＣＨ２－、－ＣＨ（ＣＨ３）－、－Ｃ（ＣＨ３）２－又は－Ｃ（ＣＦ３）２－、さらに好ましくは単結合、－Ｃ（ＣＨ３）２－又は－Ｃ（ＣＦ３）２－、さらにより好ましくは単結合又は－Ｃ（ＣＦ３）２－、とりわけ好ましくは－Ｃ（ＣＦ３）２－を表す。 In the formula (5), B is a divalent hydrocarbon group preferably having a single bond or a halogen atom from the viewpoint of easily improving the transparency, elasticity and bending resistance of the optical film. more preferably a single bond, -CH 2 -, - CH 2 -CH 2 -, - CH (CH 3) -, - C (CH 3) 2 - or -C (CF 3) 2 -, more preferably a single bond , -C (CH 3 ) 2- or -C (CF 3 ) 2- , even more preferably a single bond or -C (CF 3 ) 2- , and particularly preferably -C (CF 3 ) 2- .
　本発明の好適な実施形態においては、式（５）は、式（５’）： In a preferred embodiment of the present invention, the formula (5) is the formula (5'):
Figure JPOXMLDOC01-appb-C000016
 ［式（５’）中、＊は結合手を表す］
で表される。すなわち、ポリアミドイミド樹脂は、式（１）中のＹとして、式（５’）で表される構造を含むことが好ましい。このような形態であると、光学フィルムの透明性、弾性率及び耐屈曲性を向上しやすい。
Figure JPOXMLDOC01-appb-C000016
 [In equation (5'), * represents a bond]
It is represented by. That is, the polyamide-imide resin preferably contains a structure represented by the formula (5') as Y in the formula (1). With such a form, the transparency, elastic modulus and bending resistance of the optical film can be easily improved.
　ポリアミドイミド樹脂が、式（１）中のＹが式（５）で表される構成単位を含む場合、式（１）で表される構成単位のうち、式（１）中のＹが式（５）で表される構造である構成単位の割合は、式（１）で表される構成単位の総モル量（１００モル％）に対して、好ましくは３０モル％以上、より好ましくは３５モル％以上、さらに好ましくは４０モル％以上であり、好ましくは９０モル％以下、より好ましくは８０モル％以下、さらに好ましくは７０モル％以下である。Ｙが式（５）で表される構成単位の割合が上記の下限値以上であると、樹脂の溶媒への溶解性、及び光学フィルムの透明性を向上しやすい。また、上記の上限値以下であると、光学フィルムの弾性率を高めやすく、かつ光学フィルムの耐力を向上しやすい。なお、式（１）中のＹが式（５）で表される構成単位の割合は、例えば１Ｈ－ＮＭＲを用いて測定することができ、又は原料の仕込み比から算出することもできる。 When the polyamideimide resin contains the structural unit represented by the formula (5) in Y in the formula (1), the Y in the formula (1) is the structural unit represented by the formula (1). The ratio of the structural units having the structure represented by 5) is preferably 30 mol% or more, more preferably 35 mol, with respect to the total molar amount (100 mol%) of the structural units represented by the formula (1). % Or more, more preferably 40 mol% or more, preferably 90 mol% or less, more preferably 80 mol% or less, still more preferably 70 mol% or less. When the proportion of the structural unit in which Y is represented by the formula (5) is at least the above lower limit value, the solubility of the resin in the solvent and the transparency of the optical film can be easily improved. Further, when it is not more than the above upper limit value, it is easy to increase the elastic modulus of the optical film and to improve the proof stress of the optical film. The ratio of the structural units in which Y in the formula (1) is represented by the formula (5) can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
　本発明の一実施形態において、式（１）中のＹが式（５）で表される構成単位を含む場合、Ｙが式（３）で表される構成単位及びＹが式（５）で表される構成単位との合計割合は、式（１）で表される構成単位の総モル量に対して、好ましくは５０モル％以上、より好ましくは７０モル％以上、さらに好ましくは９０モル％以上であり、好ましくは１００モル％以下である。該合計割合が上記範囲であると、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい。なお、該合計割合は、例えば１Ｈ－ＮＭＲを用いて測定することができ、又は原料の仕込み比から算出することもできる。 In one embodiment of the present invention, when Y in the formula (1) includes a structural unit represented by the formula (5), Y is the structural unit represented by the formula (3) and Y is the structural unit represented by the formula (5). The total ratio with the structural unit represented is preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 90 mol%, based on the total molar amount of the structural unit represented by the formula (1). The above is preferably 100 mol% or less. When the total ratio is within the above range, the proof stress, breaking strain, elastic modulus and transparency of the optical film can be easily improved. The total ratio can be measured using, for example, 1 H-NMR, or can be calculated from the raw material charging ratio.
　式（１）中、Ｘは、２価の有機基を表し、好ましくは炭素数４～４０の２価の有機基を表す。 In the formula (1), X represents a divalent organic group, preferably a divalent organic group having 4 to 40 carbon atoms.
　本発明のポリアミドイミド樹脂は、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、式（１）中、Ｘは、好ましくは２価の芳香族基、２価の脂環族基、及び２価の脂肪族基の少なくとも１種、より好ましくは２価の芳香族基を含む。２価の芳香族基としては、例えば式（３）中のＲ２～Ｒ５として上記に例示の１価の芳香族炭化水素基中の水素原子のうち、１つの水素原子が結合手に置き換わった２価の芳香族炭化水素基；該２価の芳香族炭化水素基のうち、少なくとも１つ以上を連結基、例えば後述のＶ１などの連結基により結合させた基が挙げられる。２価の脂環族基としては、例えば式（３）中のＲ２～Ｒ５として上記に例示の１価の脂環族炭化水素基中の水素原子のうち、１つの水素原子が結合手に置き換わった２価の脂環族炭化水素基；該２価の脂環族炭化水素基のうち、少なくとも１つ以上を連結基、例えば後述のＶ１等の連結基により結合させた基が挙げられる。２価の脂肪族基としては、例えば式（３）中のＲ２～Ｒ５として上記に例示の１価の脂肪族炭化水素基中の水素原子のうち、１つの水素原子が結合手に置き換わった２価の脂肪族炭化水素基；該２価の脂肪族炭化水素基のうち、少なくとも１つ以上を連結基、例えば後述のＶ１等の連結基により結合させた基が挙げられる。 From the viewpoint that the polyamideimide resin of the present invention can easily improve the strength, breaking strain, elasticity and transparency of the optical film, in the formula (1), X is preferably a divalent aromatic group and a divalent fat. It contains at least one of a cyclic group and a divalent aliphatic group, more preferably a divalent aromatic group. As the divalent aromatic group, for example, one hydrogen atom among the hydrogen atoms in the monovalent aromatic hydrocarbon group exemplified above as R 2 to R 5 in the formula (3) is replaced with a bond. divalent aromatic hydrocarbon groups; one of the divalent aromatic hydrocarbon group, at least one or more linking groups include, for example, groups obtained by binding the linking group such as V 1 of the later. Examples of the divalent alicyclic group, such as those of the formula (3) of the hydrogen atoms in the monovalent alicyclic hydrocarbon group exemplified above as R 2 ~ R 5 in, one hydrogen atom is bond include one of the divalent alicyclic hydrocarbon group, at least one or more linking groups, for example bound by a linking group such as V 1 of the later group; divalent alicyclic hydrocarbon group replaced with Be done. Examples of the divalent aliphatic groups, such as the formula (3) of the hydrogen atoms in the monovalent aliphatic hydrocarbon group exemplified above as R 2 ~ R 5 in, replacing one of the hydrogen atoms have bond divalent aliphatic hydrocarbon groups; among the divalent aliphatic hydrocarbon group, at least one or more linking groups include, for example, groups obtained by binding the linking group such as V 1 of the later.
　式（１）中、Ｘは、好ましくは環状構造（脂環、芳香環、ヘテロ環構造など）を有する炭素数４～４０の２価の有機基、より好ましくは炭素数４～４０の２価の芳香族基及び炭素数４～４０の２価の脂環族基、さらに好ましくは炭素数４～４０の２価の芳香族基を表す。該有機基は、有機基中の水素原子が炭化水素基又はフッ素置換された炭化水素基で置換されていてもよく、その場合、炭化水素基及びフッ素置換された炭化水素基の炭素数は好ましくは１～８である。本発明の一実施形態において、本発明のポリアミドイミド樹脂は、複数種のＸを含み得、複数種のＸは、互いに同一であっても異なっていてもよい。Ｘとしては、式（１０）、式（１１）、式（１２）、式（１３）、式（１４）、式（１５）、式（１６）、式（１７）及び式（１８）で表される基；それらの式（１０）～式（１８）で表される基中の水素原子がメチル基、フルオロ基、クロロ基又はトリフルオロメチル基で置換された基が例示される。 In the formula (1), X is preferably a divalent organic group having 4 to 40 carbon atoms having a cyclic structure (ali ring, aromatic ring, heterocyclic structure, etc.), and more preferably divalent group having 4 to 40 carbon atoms. Represents an aromatic group and a divalent alicyclic group having 4 to 40 carbon atoms, more preferably a divalent aromatic group having 4 to 40 carbon atoms. In the organic group, the hydrogen atom in the organic group may be substituted with a hydrocarbon group or a hydrocarbon group substituted with fluorine, in which case the number of carbon atoms of the hydrocarbon group and the hydrocarbon group substituted with fluorine is preferable. Is 1-8. In one embodiment of the present invention, the polyamide-imide resin of the present invention may contain a plurality of types of X, and the plurality of types of X may be the same as or different from each other. X is represented by the formula (10), the formula (11), the formula (12), the formula (13), the formula (14), the formula (15), the formula (16), the formula (17) and the formula (18). Groups to be; Examples thereof include groups in which the hydrogen atom in the groups represented by the formulas (10) to (18) is replaced with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group.
Figure JPOXMLDOC01-appb-C000017
 なお、式（１０）～式（１８）における環上の水素原子は、炭素数１～６のアルキル基、炭素数１～６のアルコキシ基又は炭素数６～１２のアリール基で置換されていてもよい。炭素数１～６のアルキル基、炭素数１～６のアルコキシ基及び炭素数６～１２のアリール基としては、それぞれ、式（３）のＲ１として上記に例示のものが挙げられる。
Figure JPOXMLDOC01-appb-C000017
 The hydrogen atom on the ring in the formulas (10) to (18) is substituted with an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms. May be good. An alkyl group having 1 to 6 carbon atoms, the aryl group an alkoxy group and 6 to 12 carbon atoms having 1 to 6 carbon atoms, respectively, exemplified above are mentioned as R 1 of formula (3).
　式（１０）～式（１８）中、＊は結合手を表し、Ｖ１、Ｖ２及びＶ３は、互いに独立に、単結合、－Ｏ－、－Ｓ－、－ＣＨ２－、－ＣＨ２－ＣＨ２－、－ＣＨ（ＣＨ３）－、－Ｃ（ＣＨ３）２－、－Ｃ（ＣＦ３）２－、－ＳＯ２－、－ＣＯ－又は－Ｎ（Ｑ）－を表す。ここで、Ｑはハロゲン原子を有してもよい炭素数１～１２の１価の炭化水素基を表す。
　ハロゲン原子を有してもよい炭素数１～１２の１価の炭化水素基としては、式（３）のＲ２～Ｒ５におけるハロゲン原子を有してもよい１価の炭化水素基として上記に例示のものが挙げられる。
　１つの例は、Ｖ１及びＶ３が単結合、－Ｏ－又は－Ｓ－であり、かつ、Ｖ２が－ＣＨ２－、－Ｃ（ＣＨ３）２－、－Ｃ（ＣＦ３）２－又は－ＳＯ２－である。Ｖ１とＶ２との各環に対する結合位置、及び、Ｖ２とＶ３との各環に対する結合位置は、互いに独立に、各環に対して好ましくはメタ位又はパラ位、より好ましくはパラ位である。 In equations (10) to (18), * represents a bond, and V 1 , V 2 and V 3 are independent of each other, single bond, -O-, -S-, -CH 2- , -CH. 2- CH 2- , -CH (CH 3 )-, -C (CH 3 ) 2- , -C (CF 3 ) 2- , -SO 2- , -CO- or -N (Q)-represented. Here, Q represents a monovalent hydrocarbon group having 1 to 12 carbon atoms which may have a halogen atom.
Examples of the monovalent hydrocarbon group which may having 1 to 12 carbon atoms which may have a halogen atom, said as R 2 1 which may have a halogen atom in ~ R 5 divalent hydrocarbon group of the formula (3) Examples are given in.
In one example, V 1 and V 3 are single bonds, -O- or -S-, and V 2 is -CH 2- , -C (CH 3 ) 2- , -C (CF 3 ) 2. -Or-SO 2- . The bonding positions of V 1 and V 2 with respect to each ring and the bonding positions of V 2 and V 3 with respect to each ring are independent of each other, preferably in the meta position or para position with respect to each ring, and more preferably in the para position. It is a place.
　本発明の好適な実施形態では、本発明のポリアミドイミド樹脂は、式（１）中のＸとして、式（４）： In a preferred embodiment of the present invention, the polyamide-imide resin of the present invention is represented by the formula (4): X in the formula (1).
Figure JPOXMLDOC01-appb-C000018
 ［式（４）中、Ａは、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＡ１）－又は－Ｓｉ（ＲＡ２）２－を表し、ＲＡ１及びＲＡ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表し、Ｒ６は互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、ｓは、互いに独立に、０～４の整数を表し、＊は結合手を表す］
で表される構造を含み得る。このような形態であると、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい。また、式（１）で表される構成単位は、Ｘとして式（４）で表される基を１種又は複数種含んでいてもよい。
Figure JPOXMLDOC01-appb-C000018
 [In formula (4), A is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-,-. PO -, - PO 2 -, - N (R A1) - , or -Si (R A2) 2 - represents, R A1 and R A2 are, independently of one another, may have a hydrogen atom, or a halogen atom Representing an alkyl group, R 6 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group independently of each other, which may have a halogen atom or a halogen atom, and s represents 0 to 4 independently of each other. Represents an integer of, * represents a bond]
It may include a structure represented by. With such a form, it is easy to improve the proof stress, breaking strain, elastic modulus and transparency of the optical film. Further, the structural unit represented by the formula (1) may contain one or more groups represented by the formula (4) as X.
　式（４）中、Ｒ６は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表す。ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、及びアリールオキシ基としては、それぞれ、式（３）のＲ１として上記に例示のものが挙げられる。 In formula (4), R 6 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, which may have a halogen atom or a halogen atom independently of each other. Halogen atom, may have a halogen atom, an alkyl group, an alkoxy group, the aryl group, and aryloxy group, respectively, exemplified above are mentioned as R 1 of formula (3).
　これらの中でも、Ｒ６は、互いに独立に、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、好ましくは炭素数１～６のアルキル基又は炭素数１～６のハロゲン化アルキル基、より好ましくは炭素数１～６のアルキル基又は炭素数１～６のフルオロアルキル基（好ましくはパーフルオロアルキル基）、より好ましくはメチル基、クロロ基又はトリフルオロメチル基である。ｓは、互いに独立に、０～４の整数を表し、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、好ましくは１～３の整数、より好ましくは１又は２、さらに好ましくは１である。
　本発明の好適な実施形態では、各ベンゼン環において、ｓが１であり、－Ａ－を基準とするオルト位にＲ６が置換し、かつＲ６がメチル基、フルオロ基、クロロ基又はトリフルオロメチル基であり得る。 Among these, R 6 is preferably an alkyl group having 1 to 6 carbon atoms or a halogen having 1 to 6 carbon atoms from the viewpoint of easily improving the strength, breaking strain, elasticity and transparency of the optical film independently of each other. An alkyl group is more preferably an alkyl group having 1 to 6 carbon atoms or a fluoroalkyl group having 1 to 6 carbon atoms (preferably a perfluoroalkyl group), and more preferably a methyl group, a chloro group or a trifluoromethyl group. s represents an integer of 0 to 4 independently of each other, and is preferably an integer of 1 to 3, more preferably 1 or 2, from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film. More preferably, it is 1.
In a preferred embodiment of the present invention, in each benzene ring, s is 1, R 6 is substituted at the ortho position relative to —A—, and R 6 is a methyl group, a fluoro group, a chloro group or a tri. It can be a fluoromethyl group.
　式（４）中、結合手の位置は、互いに独立に、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、－Ａ－を基準に、好ましくはメタ位又はパラ位、より好ましくはパラ位である。 In the formula (4), the positions of the joints are preferably the meta-position or the para-position based on -A- from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film independently of each other. , More preferably the para position.
　式（４）中、Ａは、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＡ１）－又は－Ｓｉ（ＲＡ２）２－を表し、ＲＡ１及びＲＡ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表す。 In formula (4), A is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-, -PO. -, -PO 2- , -N ( RA1 )-or-Si ( RA2 ) 2- represents, RA1 and RA2 may have a hydrogen atom or a halogen atom independently of each other. Represents a group.
　ハロゲン原子を有してもよい２価の炭化水素基としては、式（３）のＲ２～Ｒ５におけるハロゲン原子を有してもよい１価の炭化水素基のうち、水素原子をさらに１つ除いた２価の基が挙げられる。ハロゲン原子を有してもよい２価の炭化水素基は、その基に含まれる水素原子のうち、２つの水素原子に代わって環を形成、すなわち、該２つの水素原子を結合手に代え、その２つの結合手を連結させて環を形成してもよく、該環としては、例えば炭素数３～１２のシクロアルカン環等が挙げられる。また、式（４）中のＡに含まれる－Ｎ（ＲＡ１）－及び－Ｓｉ（ＲＡ２）２－のＲＡ１及びＲＡ２におけるハロゲン原子を有してもよいアルキル基としては、式（３）中のＲ１におけるハロゲン原子を有してもよいアルキル基として上記に例示のものが挙げられる。 Examples of the divalent hydrocarbon group which may have a halogen atom, of the R 2 ~ R monovalent that may have a halogen atom in the 5 hydrocarbon radical of the formula (3), further a hydrogen atom 1 Excluded divalent groups can be mentioned. A divalent hydrocarbon group, which may have a halogen atom, forms a ring in place of two hydrogen atoms among the hydrogen atoms contained in the group, that is, the two hydrogen atoms are replaced by a bonder. The two bonds may be connected to form a ring, and examples of the ring include a cycloalcan ring having 3 to 12 carbon atoms. Further, equation (4) -N contained A in (R A1) - and -Si (R A2) 2 - Examples of the alkyl group which may have a halogen atom in R A1 and R A2 of the formula ( Examples of the alkyl group which may have a halogen atom in R 1 in 3) are mentioned above.
　式（４）中、Ａは、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、好ましくは単結合、－ＣＨ２－、－ＣＨ２－ＣＨ２－、－ＣＨ（ＣＨ３）－、－Ｃ（ＣＨ３）２－又は－Ｃ（ＣＦ３）２－、より好ましくは単結合、－Ｃ（ＣＨ３）２－又は－Ｃ（ＣＦ３）２－、さらに好ましくは単結合又は－Ｃ（ＣＦ３）２－、とりわけ好ましくは単結合を表す。 Wherein (4), A is yield strength of the optical film, fracture strain, from the viewpoint of easily improving the elastic modulus and transparency, preferably a single bond, -CH 2 -, - CH 2 -CH 2 -, - CH ( CH 3 )-, -C (CH 3 ) 2 -or-C (CF 3 ) 2- , more preferably single bond, -C (CH 3 ) 2- or -C (CF 3 ) 2- , even more preferably. Represents a single bond or -C (CF 3 ) 2- , particularly preferably a single bond.
　本発明の好適な実施形態では、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、式（４）中、Ｒ６は、互いに独立に、炭素数１～６のハロゲン化アルキル基を表し、ｓは１又は２、Ａは単結合、－Ｃ（ＣＨ３）２－又は－Ｃ（ＣＦ３）２－を表す。 In a preferred embodiment of the present invention, from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film, in the formula (4), R 6 is a halogen having 1 to 6 carbon atoms independently of each other. Represents an alkyl group, s is 1 or 2, A is a single bond, -C (CH 3 ) 2- or -C (CF 3 ) 2-.
　本発明の好適な形態においては、式（４）は、式（４’）： In a preferred embodiment of the present invention, the formula (4) is the formula (4') :.
Figure JPOXMLDOC01-appb-C000019
 で表される。すなわち、ポリアミドイミド樹脂は、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、式（１）中のＸとして、式（４’）で表される構造を含むことが好ましい。
Figure JPOXMLDOC01-appb-C000019
 It is represented by. That is, the polyamide-imide resin may include a structure represented by the formula (4') as X in the formula (1) from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film. preferable.
　式（１）で表される構成単位のうち、式（１）中のＸが式（４）で表される構造である構成単位の割合は、式（１）で表される構成単位の総モル量（１００モル％）に対して、好ましくは５０モル％以上、より好ましくは７０モル％以上、さらに好ましくは８０モル％以上であり、好ましくは１００モル％以下である。Ｘが式（４）で表される構成単位の割合が上記の下限値以上であると、光学フィルムの透明性を向上しやすい。また、上記の上限値以下であると、光学フィルムの耐力を向上しやすい。なお、式（１）中のＸが式（４）で表される構成単位の割合は、例えば１Ｈ－ＮＭＲを用いて測定することができ、又は原料の仕込み比から算出することもできる。 Of the structural units represented by the formula (1), the ratio of the structural units in which X in the formula (1) is the structure represented by the formula (4) is the total of the structural units represented by the formula (1). With respect to the molar amount (100 mol%), it is preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 80 mol% or more, and preferably 100 mol% or less. When the ratio of the structural unit in which X is represented by the formula (4) is at least the above lower limit value, the transparency of the optical film can be easily improved. Further, when it is not more than the above upper limit value, the proof stress of the optical film is likely to be improved. The ratio of the structural units in which X in the formula (1) is represented by the formula (4) can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
　式（２）中、Ｚは２価の有機基を表し、好ましくは炭素数１～８の炭化水素基又はフッ素置換された炭素数１～８の炭化水素基を有してもよい、炭素数４～４０の２価の有機基を表し、より好ましくは炭素数１～８の炭化水素基又はフッ素置換された炭素数１～８の炭化水素基を有してもよい、環状構造を有する炭素数４～４０の２価の有機基を表す。環状構造としては、脂環、芳香環、ヘテロ環構造が挙げられる。脂環及び芳香環を有する２価の有機基としては、式（２０）、式（２１）、式（２２）、式（２３）、式（２４）、式（２５）、式（２６）、式（２７）、式（２８）及び式（２９）： In the formula (2), Z represents a divalent organic group, preferably having a hydrocarbon group having 1 to 8 carbon atoms or a fluorine-substituted hydrocarbon group having 1 to 8 carbon atoms. A carbon having a cyclic structure representing a divalent organic group of 4 to 40, more preferably having a hydrocarbon group having 1 to 8 carbon atoms or a fluorine-substituted hydrocarbon group having 1 to 8 carbon atoms. Represents a divalent organic group of numbers 4-40. Examples of the cyclic structure include an alicyclic ring, an aromatic ring, and a heterocyclic structure. Examples of the divalent organic group having an alicyclic ring and an aromatic ring include the formula (20), the formula (21), the formula (22), the formula (23), the formula (24), the formula (25), and the formula (26). Equation (27), Equation (28) and Equation (29):
Figure JPOXMLDOC01-appb-C000020
 ［式（２０）～式（２９）中、Ｗ１は、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基（例えば－ＣＨ２－、－ＣＨ２－ＣＨ２－、－ＣＨ（ＣＨ３）－、－Ｃ（ＣＨ３）２－、－Ｃ（ＣＦ３）２－）、－Ａｒ－、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＷ１）－又は－Ｓｉ（ＲＷ２）２－、－Ｏ－Ａｒ－Ｏ－、－Ａｒ－Ｏ－Ａｒ－、－Ａｒ－ＣＨ２－Ａｒ－、－Ａｒ－Ｃ（ＣＨ３）２－Ａｒ－又は－Ａｒ－ＳＯ２－Ａｒ－を表し、ここで、Ａｒは、互いに独立に、フッ素原子を有してもよい炭素数６～２０のアリーレン基（例えばフェニレン基）を表し、ＲＷ１及びＲＷ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表し、＊は結合手を表す］
で表される基の結合手のうち、隣接しない２つが水素原子に置き換わった基及び炭素数６以下の２価の鎖式炭化水素基が挙げられる。ヘテロ環構造を有する２価の有機基としてはチオフェン環骨格を有する基が挙げられる。光学フィルムの黄色度（以下、ＹＩ値と記載することがある）を抑制しやすい観点から、式（２０）～式（２９）で表される基の結合手のうち、隣接しない２つが水素原子に置き換わった基、及び、チオフェン環骨格を有する基が好ましい。
Figure JPOXMLDOC01-appb-C000020
 [In formulas (20) to (29), W 1 is a divalent hydrocarbon group (for example, -CH 2- , -CH) which may have a single bond, -O-, a diphenylmethylene group, or a halogen atom. 2- CH 2- , -CH (CH 3 )-, -C (CH 3 ) 2- , -C (CF 3 ) 2- ), -Ar-, -SO 2- , -S-, -CO-, -PO -, - PO 2 -, - N (R W1) - , or -Si (R W2) 2 -, - O-Ar-O -, - Ar-O-Ar -, - Ar-CH 2 -Ar- , -Ar-C (CH 3 ) 2- Ar- or -Ar-SO 2- Ar-, where Ar is an arylene having 6 to 20 carbon atoms which may have a fluorine atom independently of each other. Represents a group (eg, a phenylene group), RW1 and RW2 represent an alkyl group that may have a hydrogen atom or a halogen atom independently of each other, and * represents a bond.]
Among the group bonds represented by, examples thereof include a group in which two non-adjacent groups are replaced with hydrogen atoms and a divalent chain hydrocarbon group having 6 or less carbon atoms. Examples of the divalent organic group having a heterocyclic structure include a group having a thiophene ring skeleton. From the viewpoint of easily suppressing the yellowness of the optical film (hereinafter, may be referred to as YI value), two non-adjacent group bonds represented by the formulas (20) to (29) are hydrogen atoms. A group replaced with and a group having a thiophene ring skeleton are preferable.
　式（２）中のＺとしては、式（２０’）、式（２１’）、式（２２’）、式（２３’）、式（２４’）、式（２５’）、式（２６’）、式（２７’）、式（２８’）及び式（２９’）： The Z in the formula (2) includes the formula (20'), the formula (21'), the formula (22'), the formula (23'), the formula (24'), the formula (25'), and the formula (26'). ), Equation (27'), Equation (28') and Equation (29'):
Figure JPOXMLDOC01-appb-C000021
 ［式（２０’）～式（２９’）中、Ｗ１及び＊は、式（２０）～式（２９）において定義した通りである］
で表される２価の有機基がより好ましい。なお、式（２０）～式（２９）及び式（２０’）～式（２９’）における環上の水素原子は、炭素数１～６のアルキル基、炭素数１～６のアルコキシ基、又は炭素数６～１２のアリール基で置換されていてもよい。炭素数１～６のアルキル基、炭素数１～６のアルコキシ基及び炭素数６～１２のアリール基としては、それぞれ、式（３）のＲ１として上記に例示のものが挙げられる。
Figure JPOXMLDOC01-appb-C000021
 In formula (20 ') to formula (29'), W 1 and * are as defined in formula (20) to (29)]
The divalent organic group represented by is more preferable. The hydrogen atom on the ring in the formulas (20) to (29) and the formulas (20') to (29') is an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. It may be substituted with an aryl group having 6 to 12 carbon atoms. An alkyl group having 1 to 6 carbon atoms, the aryl group an alkoxy group and 6 to 12 carbon atoms having 1 to 6 carbon atoms, respectively, exemplified above are mentioned as R 1 of formula (3).
　本発明の好適な実施形態では、本発明のポリアミドイミド樹脂は、式（２）中のＺとして、式（６）： In a preferred embodiment of the present invention, the polyamide-imide resin of the present invention has Z in the formula (2) as the formula (6):
Figure JPOXMLDOC01-appb-C000022
 ［式（６）中、Ｗは、互いに独立に、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＣ１）－又は－Ｓｉ（ＲＣ２）２－を表し、ＲＣ１及びＲＣ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表し、Ｒ８は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、ｐは、互いに独立に、０～４の整数を表し、ｑは０～４の整数を表し、＊は結合手を表す］
で表される構造を含み得る。このような形態であると、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい。また、式（２）で表される構成単位は、Ｚとして式（６）で表される基を１種又は複数種含んでいてもよい。
Figure JPOXMLDOC01-appb-C000022
 Wherein (6), W, independently of one another, a single bond, -O-, diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2 -, - S - , - It represents CO-, -PO-, -PO 2- , -N ( RC1 )-or-Si ( RC2 ) 2- , and RC1 and RC2 have hydrogen atom or halogen atom independently of each other. R 8 represents an alkyl group which may have a halogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, and p is independent of each other. , 0 to 4 represents an integer, q represents an integer from 0 to 4, and * represents a bond.]
It may include a structure represented by. With such a form, it is easy to improve the proof stress, breaking strain, elastic modulus and transparency of the optical film. Further, the structural unit represented by the formula (2) may contain one or more groups represented by the formula (6) as Z.
　式（６）において、Ｗの結合位置は、互いに独立に、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、結合手を基準に、メタ位又はパラ位であることが好ましく、パラ位であることがより好ましい。 In the formula (6), the bonding position of W is the meta position or the para position with respect to the bonding hand from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film independently of each other. Is preferable, and the para position is more preferable.
　本発明の好適な形態においては、式（６）は、式（６’）： In a preferred embodiment of the present invention, the formula (6) is the formula (6'):
Figure JPOXMLDOC01-appb-C000023
 ［式（６’）中、Ｗ、Ｒ８、ｐ及びｑは式（６）において定義した通りである］
で表される。すなわち、本発明のポリアミドイミド樹脂は、式（２）中のＺとして式（６’）で表される構造を含むことが好ましい。このような形態であると、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい。
Figure JPOXMLDOC01-appb-C000023
 [In equation (6'), W, R 8 , p and q are as defined in equation (6)]
It is represented by. That is, the polyamide-imide resin of the present invention preferably contains a structure represented by the formula (6') as Z in the formula (2). With such a form, it is easy to improve the proof stress, breaking strain, elastic modulus and transparency of the optical film.
　式（６）及び式（６’）中、Ｒ８は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表す。ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、及びアリールオキシ基としては、それぞれ、式（３）のＲ１として上記に例示のものが挙げられる。 In formulas (6) and (6'), R 8 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, which may have a halogen atom or a halogen atom independently of each other. Halogen atom, may have a halogen atom, an alkyl group, an alkoxy group, the aryl group, and aryloxy group, respectively, exemplified above are mentioned as R 1 of formula (3).
　これらの中でも、Ｒ８は、互いに独立に、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、好ましくはハロゲン原子を有してもよい、炭素数１～６のアルキル基又は炭素数１～６のアルコキシ基、より好ましくは炭素数１～３のアルキル基又は炭素数１～３のアルコキシ基を表す。ｐは、互いに独立に、０～４の整数を表し、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、好ましくは０～２の整数、より好ましくは０又は１、さらに好ましくは０である。 Among these, R 8 is an alkyl having 1 to 6 carbon atoms, which may preferably have a halogen atom from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film independently of each other. It represents a group or an alkoxy group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms. p represents an integer of 0 to 4 independently of each other, and is preferably an integer of 0 to 2, more preferably 0 or 1, from the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film. More preferably, it is 0.
　式（６）及び式（６’）中、Ｗは、互いに独立に、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＣ１）－又は－Ｓｉ（ＲＣ２）２－を表し、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、好ましくは－Ｏ－又は－Ｓ－、より好ましくは－Ｏ－を表す。ＲＣ１及びＲＣ２は、互いに独立に、水素原子又はハロゲン原子を有してもよい炭素数１～１２の１価の炭化水素基を表す。ハロゲン原子を有してもよい炭素数１～１２の１価の炭化水素基としては、式（３）のＲ２～Ｒ５におけるハロゲン原子を有してもよい１価の炭化水素基として上記に例示のものが挙げられる。 In the formula (6) and (6 '), W, independently of one another, a single bond, -O-, diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2 -, Represents -S-, -CO-, -PO-, -PO 2- , -N ( RC1 )-or -Si ( RC2 ) 2-, and indicates the yield strength, breaking strain, elastic modulus and transparency of the optical film. From the viewpoint of easy improvement, it preferably represents —O— or —S—, and more preferably —O—. RC1 and RC2 represent monovalent hydrocarbon groups having 1 to 12 carbon atoms which may have hydrogen atoms or halogen atoms independently of each other. Examples of the monovalent hydrocarbon group which may having 1 to 12 carbon atoms which may have a halogen atom, said as R 2 1 which may have a halogen atom in ~ R 5 divalent hydrocarbon group of the formula (3) Examples are given in.
　式（６）及び式（６’）中、ｑは、０～４の範囲の整数であり、ｑがこの範囲内であると、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい。式（６）及び式（６’）中のｑは、好ましくは０～３の範囲の整数、より好ましくは０～２の範囲の整数である。 In the formulas (6) and (6'), q is an integer in the range of 0 to 4, and when q is in this range, the proof stress, breaking strain, elastic modulus and transparency of the optical film are improved. Cheap. Q in the formula (6) and the formula (6') is preferably an integer in the range of 0 to 3, and more preferably an integer in the range of 0 to 2.
　ｑが０である式（６）又は式（６’）で表される構造は、例えばテレフタル酸又はイソフタル酸に由来する構造であり、該構造は、中でも、式（６）又は式（６’）中のｐ及びｑがそれぞれ０、又は、ｑが０及びｐが１若しくは２（好ましくはＲ８が炭素数１～３のアルキル基又はフッ素化アルキル基又は炭素数１～３のアルコキシ基）である構造であることが好ましい。光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい観点から、ポリアミドイミド樹脂は、テレフタル酸に由来する構造を含む、式（２）で表される構成単位を含むことが好ましい。ポリアミドイミド樹脂は式（２）中のＺとして、式（６）又は式（６’）で表される構成単位を１種又は２種類以上含んでいてもよい。 The structure represented by the formula (6) or the formula (6') in which q is 0 is, for example, a structure derived from terephthalic acid or isophthalic acid, and the structure is, among others, the formula (6) or the formula (6'). ) Are 0, or q is 0 and p is 1 or 2 (preferably R 8 is an alkyl group having 1 to 3 carbon atoms or a fluorinated alkyl group or an alkoxy group having 1 to 3 carbon atoms). It is preferable that the structure is. From the viewpoint of easily improving the proof stress, breaking strain, elastic modulus and transparency of the optical film, the polyamide-imide resin preferably contains a structural unit represented by the formula (2), which includes a structure derived from terephthalic acid. The polyamide-imide resin may contain one or more structural units represented by the formula (6) or the formula (6') as Z in the formula (2).
　本発明の一実施形態において、式（２）中のＺとして、式（６）で表される構造を含む場合、式（２）で表される構成単位のうち、Ｘが式（６）で表される構成単位の割合は、式（２）で表される構成単位の総モル量に対して、好ましくは３０モル％以上、より好ましくは５０モル％以上、さらに好ましくは７０モル％以上であり、好ましくは１００モル％以下である。式（２）中のＺが式（６）で表される構成単位の割合が上記の下限値以上であると、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい。該割合が上記の上限値以下であると、式（６）由来のアミド結合間水素結合による樹脂ワニスの粘度上昇を抑制し、フィルムの加工性を向上しやすい。なお、式（２）中のＺが式（６）で表される構成単位の割合は、例えば１Ｈ－ＮＭＲを用いて測定することができ、又は原料の仕込み比から算出することもできる。 In one embodiment of the present invention, when Z in the formula (2) includes a structure represented by the formula (6), among the structural units represented by the formula (2), X is the formula (6). The ratio of the constituent units represented is preferably 30 mol% or more, more preferably 50 mol% or more, still more preferably 70 mol% or more, based on the total molar amount of the constituent units represented by the formula (2). Yes, preferably 100 mol% or less. When the ratio of the structural unit in which Z in the formula (2) is represented by the formula (6) is not more than the above lower limit value, the proof stress, breaking strain, elastic modulus and transparency of the optical film are likely to be improved. When the ratio is not more than the above upper limit value, the increase in viscosity of the resin varnish due to the hydrogen bond between the amide bonds derived from the formula (6) is suppressed, and the processability of the film is easily improved. The ratio of the structural units in which Z in the formula (2) is represented by the formula (6) can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
　本発明の一実施形態において、式（２）中のＺとして、式（６）で表される構造を含む場合、式（２）で表される構成単位のうち、Ｘが式（６）で表される構成単位の割合は、式（１）で表される構成単位と式（２）で表される構成単位との総モル量に対して、好ましくは５モル％以上、より好ましくは１５モル％以上、さらに好ましくは３０モル％以上、とりわけ好ましくは５０モル％以上であり、好ましくは１００モル％以下である。式（２）中のＺが式（６）で表される構成単位の割合が上記の下限値以上であると、光学フィルムの耐力、破断歪、弾性率及び透明性を向上しやすい。該割合が上記の上限値以下であると、式（６）由来のアミド結合間水素結合による樹脂ワニスの粘度上昇を抑制し、フィルムの加工性を向上しやすい。なお、式（２）中のＺが式（６）で表される構成単位の割合は、例えば１Ｈ－ＮＭＲを用いて測定することができ、又は原料の仕込み比から算出することもできる。 In one embodiment of the present invention, when Z in the formula (2) includes a structure represented by the formula (6), among the structural units represented by the formula (2), X is the formula (6). The ratio of the constituent units represented is preferably 5 mol% or more, more preferably 15 with respect to the total molar amount of the constituent units represented by the formula (1) and the constituent units represented by the formula (2). It is mol% or more, more preferably 30 mol% or more, particularly preferably 50 mol% or more, and preferably 100 mol% or less. When the ratio of the structural unit in which Z in the formula (2) is represented by the formula (6) is not more than the above lower limit value, the proof stress, breaking strain, elastic modulus and transparency of the optical film are likely to be improved. When the ratio is not more than the above upper limit value, the increase in viscosity of the resin varnish due to the hydrogen bond between the amide bonds derived from the formula (6) is suppressed, and the processability of the film is easily improved. The ratio of the structural units in which Z in the formula (2) is represented by the formula (6) can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
　ポリアミドイミド樹脂が、式（２）中のＺが上記の式（２０’）～式（２９’）のいずれかで表される構成単位を有する場合、特に式（２）中のＺが式（６’）で表される構成単位を有する場合、ポリアミドイミド樹脂は、式（１）及び式（２）で表される構成単位に加えて、次の式（ｄ１）： When the polyamide-imide resin has a structural unit in which Z in the formula (2) is represented by any of the above formulas (20') to (29'), Z in the formula (2) is particularly in the formula (2). When having the structural unit represented by 6'), the polyamide-imide resin has the following structural unit (d1): in addition to the structural unit represented by the formula (1) and the formula (2).
Figure JPOXMLDOC01-appb-C000024
 ［式（ｄ１）中、Ｒ２４は、互いに独立に、水素原子、炭素数１～６のアルキル基、炭素数１～６のアルコキシ基又は炭素数６～１２のアリール基を表し、Ｒ２５は、Ｒ２４又は－Ｃ（＝Ｏ）－＊を表し、＊は結合手を表す］
で表されるカルボン酸由来の構成単位をさらに有することが、樹脂の溶解性を向上しやすくして、樹脂の加工性を高める観点から好ましい。
Figure JPOXMLDOC01-appb-C000024
 [In the formula (d1), R 24 represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and R 25 is an independent group. , R 24 or -C (= O)-*, * represents a bond]
It is preferable to further have a carboxylic acid-derived structural unit represented by (1) from the viewpoint of facilitating the improvement of the solubility of the resin and enhancing the processability of the resin.
　Ｒ２４において、炭素数１～６のアルキル基、炭素数１～６のアルコキシ基及び炭素数６～１２のアリール基としては、それぞれ、式（３）のＲ１として上記に例示のものが挙げられる。構成単位（ｄ１）としては、具体的には、Ｒ２４及びＲ２５がいずれも水素原子である構成単位（ジカルボン酸化合物に由来する構成単位）、Ｒ２４がいずれも水素原子であり、Ｒ２５が－Ｃ（＝Ｏ）－＊を表す構成単位（トリカルボン酸化合物に由来する構成単位）などが挙げられる。 In R 24 , the alkyl group having 1 to 6 carbon atoms, the alkoxy group having 1 to 6 carbon atoms, and the aryl group having 6 to 12 carbon atoms are exemplified above as R 1 of the formula (3), respectively. Be done. Specifically, as the structural unit (d1), R 24 and R 25 are both hydrogen atoms (constituent units derived from a dicarboxylic acid compound), and R 24 is a hydrogen atom and R 25. Examples thereof include a structural unit (a structural unit derived from a tricarboxylic acid compound) representing -C (= O)-*.
　ポリアミドイミド樹脂が、式（ｄ１）で表される構成単位を含む場合、式（ｄ１）で表される構成単位の割合は、式（１）で表される構成単位と式（２）で表される構成単位との総モル量に対して、好ましくは０．０１モル％以上、より好ましくは０．１モル％以上、さらに好ましくは１モル％以上であり、好ましくは３０モル％以下、より好ましくは２０モル％以下、さらに好ましくは１０モル％以下である。該割合が上記範囲内であると、光学フィルムの弾性率を維持しつつ樹脂の溶解性を改善しやすい。なお、該割合は、例えば１Ｈ－ＮＭＲを用いて測定することができ、又は原料の仕込み比から算出することもできる。 When the polyamideimide resin contains a structural unit represented by the formula (d1), the ratio of the structural unit represented by the formula (d1) is represented by the structural unit represented by the formula (1) and the structural unit represented by the formula (2). It is preferably 0.01 mol% or more, more preferably 0.1 mol% or more, still more preferably 1 mol% or more, and preferably 30 mol% or less, based on the total molar amount of the constituent units. It is preferably 20 mol% or less, more preferably 10 mol% or less. When the ratio is within the above range, the solubility of the resin can be easily improved while maintaining the elastic modulus of the optical film. The ratio can be measured using, for example, 1 H-NMR, or can be calculated from the raw material charging ratio.
　式（２）中のＸとしては、式（１）中のＸとして上記に例示したものが挙げられ、好ましい形態も同じである。また、式（１）中のＸと式（２）中のＸは、同一であっても異なっていてもよい。本発明の一実施形態では、式（１）で表される構成単位及び／又は式（２）で表される構成単位は、Ｘとして式（４）で表される構造（又は基）を１種又は複数種含んでいてもよい。 Examples of the X in the formula (2) include those exemplified above as the X in the formula (1), and the preferred form is also the same. Further, X in the formula (1) and X in the formula (2) may be the same or different. In one embodiment of the present invention, the structural unit represented by the formula (1) and / or the structural unit represented by the formula (2) has a structure (or group) represented by the formula (4) as X. It may contain a species or a plurality of species.
　本発明の一実施形態において、式（１）及び式（２）中のＸとして、式（４）で表される構造を含む場合、Ｘが式（４）で表される構成単位の割合は、式（１）で表される構成単位及びは式（２）で表される構成単位の総モル量に対して、好ましくは３０モル％以上、より好ましくは５０モル％以上、さらに好ましくは７０モル％以上であり、好ましくは１００モル％以下である。Ｘが式（４）で表される構成単位の割合が上記の範囲内であると、光学フィルムの破断歪、弾性率及び透明性を向上しやすく、かつ、光学フィルムの耐力を向上しやすい。なお、Ｘが式（４）で表される構成単位の割合は、例えば１Ｈ－ＮＭＲを用いて測定することができ、又は原料の仕込み比から算出することもできる。 In one embodiment of the present invention, when X in the formulas (1) and (2) includes a structure represented by the formula (4), the ratio of the structural units in which X is represented by the formula (4) is , The structural unit represented by the formula (1) and the total molar amount of the structural unit represented by the formula (2) are preferably 30 mol% or more, more preferably 50 mol% or more, still more preferably 70. It is mol% or more, preferably 100 mol% or less. When the ratio of the structural unit in which X is represented by the formula (4) is within the above range, it is easy to improve the breaking strain, elastic modulus and transparency of the optical film, and it is easy to improve the proof stress of the optical film. The ratio of the structural unit in which X is represented by the formula (4) can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
　本発明のポリアミドイミド樹脂は、式（１）及び式（２）で表される構成単位に加えて、式（３０）で表される構成単位及び／又は式（３１）で表される構成単位を含んでいてもよい。 In the polyamide-imide resin of the present invention, in addition to the structural units represented by the formulas (1) and (2), the structural units represented by the formula (30) and / or the structural units represented by the formula (31). May include.
Figure JPOXMLDOC01-appb-C000025
Figure JPOXMLDOC01-appb-C000025
　式（３０）中、Ｙ１は４価の有機基を表し、好ましくは有機基中の水素原子が炭化水素基又はフッ素置換された炭化水素基で置換されていてもよい有機基を表す。Ｙ１としては、式（２０）、式（２１）、式（２２）、式（２３）、式（２４）、式（２５）、式（２６）、式（２７）、式（２８）及び式（２９）で表される基、該式（２０）～式（２９）で表される基中の水素原子がメチル基、フルオロ基、クロロ基又はトリフルオロメチル基で置換された基、並びに４価の炭素数６以下の鎖式炭化水素基が例示される。本発明の一実施形態において、式（３０）で表される構成単位は、複数種のＹ１で表される構造を含み得、複数種のＹ１は、互いに同一であっても異なっていてもよい。 In the formula (30), Y 1 represents a tetravalent organic group, and preferably represents an organic group in which the hydrogen atom in the organic group may be substituted with a hydrocarbon group or a hydrocarbon group substituted with fluorine. Examples of Y 1 include formula (20), formula (21), formula (22), formula (23), formula (24), formula (25), formula (26), formula (27), formula (28) and A group represented by the formula (29), a group in which the hydrogen atom in the groups represented by the formulas (20) to (29) is substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group, and a group. A chain hydrocarbon group having 4 or less tetravalent carbon atoms is exemplified. In one embodiment of the present invention, the structural unit represented by the formula (30) may include a structure represented by a plurality of kinds of Y 1, Y 1 of the plurality of species, they being the same or different May be good.
　式（３１）において、Ｙ２は３価の有機基であり、好ましくは有機基中の水素原子が炭化水素基又はフッ素置換された炭化水素基で置換されていてもよい有機基である。Ｙ２としては、上記の式（２０）、式（２１）、式（２２）、式（２３）、式（２４）、式（２５）、式（２６）、式（２７）、式（２８）及び式（２９）で表される基の結合手のいずれか１つが水素原子に置き換わった基、及び３価の炭素数６以下の鎖式炭化水素基が例示される。本発明の一実施形態において、式（３１）で表される構成単位は、複数種のＹ２で表される構造を含み得、複数種のＹ２は、互いに同一であっても異なっていてもよい。 In the formula (31), Y 2 is a trivalent organic group, preferably an organic group in which the hydrogen atom in the organic group may be substituted with a hydrocarbon group or a hydrocarbon group substituted with fluorine. Examples of Y 2 include the above equations (20), (21), (22), (23), (24), (25), (26), (27), and (28). ) And a group in which any one of the bonds of the group represented by the formula (29) is replaced with a hydrogen atom, and a chain hydrocarbon group having a trivalent carbon number of 6 or less are exemplified. In one embodiment of the present invention, the structural unit represented by the formula (31) may include a structure represented by a plurality of kinds of Y 2, Y 2 a plurality of species, they being the same or different May be good.
　式（３０）及び式（３１）において、Ｘ１及びＸ２は、互いに独立に、２価の有機基であり、好ましくは有機基中の水素原子が炭化水素基又はフッ素置換された炭化水素基で置換されていてもよい有機基である。Ｘ１及びＸ２としては、上記の式（１０）、式（１１）、式（１２）、式（１３）、式（１４）、式（１５）、式（１６）、式（１７）及び式（１８）で表される基；該式（１０）～式（１８）で表される基中の水素原子がメチル基、フルオロ基、クロロ基又はトリフルオロメチル基で置換された基；並びに炭素数６以下の鎖式炭化水素基が例示される。 In formulas (30) and (31), X 1 and X 2 are divalent organic groups independently of each other, and preferably a hydrocarbon group in which a hydrogen atom in the organic group is substituted with a hydrocarbon group or fluorine. It is an organic group that may be substituted with. Examples of X 1 and X 2 include the above equations (10), (11), (12), (13), (14), (15), (16), (17) and A group represented by the formula (18); a group in which the hydrogen atom in the groups represented by the formulas (10) to (18) is substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; A chain hydrocarbon group having 6 or less carbon atoms is exemplified.
　ポリアミドイミド樹脂が、式（３０）で表される構成単位、及び／又は式（３１）で表される構成単位を含む場合、式（３０）で表される構成単位及び式（３１）で表される構成単位の合計割合は、式（１）で表される構成単位と式（２）で表される構成単位との総モル量に対して、好ましくは０．０１モル％以上、より好ましくは０．１モル％以上、さらに好ましくは１モル％以上であり、好ましくは３０モル％以下、より好ましくは２０モル％以下、さらに好ましくは１０モル％以下である。該合計割合が上記範囲内であると、高弾性率の光学フィルムを得やすい。なお、該割合は、例えば、１Ｈ－ＮＭＲを用いて測定することができ、又は原料の仕込み比から算出することもできる。 When the polyamideimide resin contains a structural unit represented by the formula (30) and / or a structural unit represented by the formula (31), the structural unit represented by the formula (30) and the structural unit represented by the formula (31) are represented. The total ratio of the structural units to be formed is preferably 0.01 mol% or more, more preferably 0.01 mol% or more, based on the total molar amount of the structural units represented by the formula (1) and the structural units represented by the formula (2). Is 0.1 mol% or more, more preferably 1 mol% or more, preferably 30 mol% or less, more preferably 20 mol% or less, still more preferably 10 mol% or less. When the total ratio is within the above range, it is easy to obtain an optical film having a high elastic modulus. The ratio can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
　ポリアミドイミド樹脂において、式（１）で表される構成単位の割合は、式（１）で表される構成単位及び式（２）で表される構成単位の総モル量（１００モル％）に対して、好ましくは１０モル％以上、より好ましくは１５モル％以上、さらに好ましくは２０モル％以上、さらにより好ましくは２５モル％以上、とりわけ好ましくは３０モル％以上であり、好ましくは９０モル％以下、より好ましくは７０モル％以下、さらに好ましくは６０モル％以下、とりわけ好ましくは５０モル％以下である。ポリアミドイミド樹脂において、式（１）で表される構成単位の割合が上記下限値以上であると、式（２）中のアミド結合間の水素結合による増粘を抑制し、ポリアミドイミドワニスの粘度を低減することができ、光学部材の製造が容易である。ポリアミドイミド樹脂において、式（１）で表される構成単位の割合が上記上限値以下であると、該ポリアミドイミド樹脂を含んでなる光学フィルムは、高い表面硬度を発揮する。また、式（１）で表される構成単位の割合が上記上限値以下であると、相対的に式（２）で表される構成単位の割合が増加することにより、該ポリアミドイミド樹脂を含んでなる光学フィルムの耐力を向上しやすい。なお、上記割合は、例えば、１Ｈ－ＮＭＲを用いて測定することができ、又は原料の仕込み比から算出することもできる。 In the polyamideimide resin, the ratio of the structural units represented by the formula (1) is the total molar amount (100 mol%) of the structural units represented by the formula (1) and the structural units represented by the formula (2). On the other hand, it is preferably 10 mol% or more, more preferably 15 mol% or more, further preferably 20 mol% or more, still more preferably 25 mol% or more, particularly preferably 30 mol% or more, and preferably 90 mol% or more. Below, it is more preferably 70 mol% or less, further preferably 60 mol% or less, and particularly preferably 50 mol% or less. In the polyamide-imide resin, when the ratio of the constituent units represented by the formula (1) is equal to or higher than the above lower limit value, the thickening due to hydrogen bonds between the amide bonds in the formula (2) is suppressed, and the viscosity of the polyamide-imide varnish Can be reduced, and the manufacture of optical members is easy. In the polyamide-imide resin, when the ratio of the structural unit represented by the formula (1) is not more than the above upper limit value, the optical film containing the polyamide-imide resin exhibits high surface hardness. Further, when the ratio of the structural unit represented by the formula (1) is not more than the above upper limit value, the ratio of the structural unit represented by the formula (2) increases relatively, so that the polyamide-imide resin is contained. It is easy to improve the yield strength of the optical film made of. The above ratio can be measured using, for example, 1 1 H-NMR, or can be calculated from the raw material charging ratio.
　本発明の一実施形態では、式（１）で表される構成単位及び式（２）で表される構成単位の総量の割合は、ポリアミドイミド樹脂に含まれる全構成単位に対して、好ましくは５０モル％以上、より好ましくは７０モル％以上、さらに好ましくは８０モル％以上、とりわけ好ましくは９０モル％以上であり、好ましくは１００モル％以下である。該割合が上記下限値以上であると、光学フィルムの耐力及び透明性を向上しやすい。 In one embodiment of the present invention, the ratio of the total amount of the structural unit represented by the formula (1) and the structural unit represented by the formula (2) is preferably relative to all the structural units contained in the polyamide-imide resin. It is 50 mol% or more, more preferably 70 mol% or more, further preferably 80 mol% or more, particularly preferably 90 mol% or more, and preferably 100 mol% or less. When the ratio is at least the above lower limit value, the proof stress and transparency of the optical film are likely to be improved.
　本発明のポリアミドイミド樹脂の重量平均分子量（以下、Ｍｗと記載することがある）は、好ましくは１００，０００以上、より好ましくは１５０，０００以上、さらに好ましくは２００，０００以上、さらにより好ましくは３００，０００以上、とりわけ好ましくは４００，０００以上、とりわけより好ましくは５００，０００以上、ことさら好ましくは６００，０００以上であり、好ましくは１，５００，０００以下、より好ましくは１，２００，０００以下、さらに好ましくは１，０００，０００以下、とりわけ好ましくは８００，０００以下である。ポリアミドイミド樹脂のＭｗが上記の下限値以上であると、得られる光学フィルムの破断歪及び弾性率を向上しやすい。また、Ｍｗが上記の上限値以下であると、樹脂ワニスのゲル化を抑制しやすく、得られる光学フィルムの光学特性を向上しやすく、かつ、光学フィルムの耐力を向上しやすい。ここで、本発明のポリアミドイミド樹脂が、式（１）中のＹとして式（３）で表される構造を含む場合、該構造を有するポリアミドイミド樹脂の溶液の粘度は高くなる傾向があることがわかった。ポリアミドイミド樹脂のＭｗが大きくなることによっても樹脂溶液の粘度は高くなる傾向があるため、このような構造を含むポリアミドイミド樹脂を高分子量化することは非常に困難であった。本発明者らは種々の検討を行った結果、後述する製造条件でポリアミドイミド樹脂を製造することにより、Ｍｗを高めることができることを見出した。Ｍｗは、例えばゲル浸透クロマトグラフィー（以下、ＧＰＣと記載することがある）測定を行い、標準ポリスチレン換算によって求めることができ、例えば実施例に記載の方法により求めることができる。 The weight average molecular weight of the polyamide-imide resin of the present invention (hereinafter, may be referred to as Mw) is preferably 100,000 or more, more preferably 150,000 or more, still more preferably 200,000 or more, still more preferably. 300,000 or more, particularly preferably 400,000 or more, particularly more preferably 500,000 or more, particularly preferably 600,000 or more, preferably 1,500,000 or less, more preferably 1,200,000 or less. , More preferably 1,000,000 or less, and particularly preferably 800,000 or less. When the Mw of the polyamide-imide resin is at least the above lower limit value, it is easy to improve the breaking strain and elastic modulus of the obtained optical film. Further, when Mw is not more than the above upper limit value, gelation of the resin varnish is easily suppressed, the optical characteristics of the obtained optical film are easily improved, and the proof stress of the optical film is easily improved. Here, when the polyamide-imide resin of the present invention contains a structure represented by the formula (3) as Y in the formula (1), the viscosity of the solution of the polyamide-imide resin having the structure tends to be high. I understood. Since the viscosity of the resin solution tends to increase as the Mw of the polyamide-imide resin increases, it is very difficult to increase the molecular weight of the polyamide-imide resin containing such a structure. As a result of various studies, the present inventors have found that Mw can be increased by producing a polyamide-imide resin under the production conditions described later. Mw can be determined, for example, by performing gel permeation chromatography (hereinafter, may be referred to as GPC) measurement and converting to standard polystyrene, and can be determined, for example, by the method described in Examples.
　本発明の好適な一実施形態において、本発明のポリアミドイミド樹脂は、例えば上記の含フッ素置換基等によって導入することができる、フッ素原子等のハロゲン原子を含んでよい。ポリアミドイミド樹脂がハロゲン原子を含む場合、光学フィルムのＹＩ値を低減しやすく、かつ破断歪及び弾性率を高めやすい。また、光学フィルムの弾性率が高いと、傷及びシワ等の発生を抑制しやすい。また、光学フィルムのＹＩ値が低いと、該フィルムの透明性及び視認性を向上させやすくなる。ハロゲン原子は、好ましくはフッ素原子である。ポリアミドイミド樹脂にフッ素原子を含有させるために好ましい含フッ素置換基としては、例えばフルオロ基及びトリフルオロメチル基が挙げられる。 In a preferred embodiment of the present invention, the polyamide-imide resin of the present invention may contain a halogen atom such as a fluorine atom which can be introduced by, for example, the above-mentioned fluorine-containing substituent or the like. When the polyamide-imide resin contains halogen atoms, it is easy to reduce the YI value of the optical film, and it is easy to increase the breaking strain and elastic modulus. Further, when the elastic modulus of the optical film is high, it is easy to suppress the occurrence of scratches and wrinkles. Further, when the YI value of the optical film is low, it becomes easy to improve the transparency and visibility of the film. The halogen atom is preferably a fluorine atom. Preferred fluorine-containing substituents for containing a fluorine atom in the polyamide-imide resin include, for example, a fluoro group and a trifluoromethyl group.
　ポリアミドイミド樹脂におけるハロゲン原子の含有量は、それぞれ、ポリアミドイミド樹脂の質量を基準として、好ましくは１～４０質量％、より好ましくは５～４０質量％、さらに好ましくは５～３０質量％である。ハロゲン原子の含有量が上記の下限値以上であると、光学フィルムのＹＩ値を低減しやすく、かつ破断歪及び弾性率を高めやすい。ハロゲン原子の含有量が上記の上限値以下であると、合成がしやすくなる The content of halogen atoms in the polyamide-imide resin is preferably 1 to 40% by mass, more preferably 5 to 40% by mass, still more preferably 5 to 30% by mass, based on the mass of the polyamide-imide resin. When the halogen atom content is at least the above lower limit value, the YI value of the optical film can be easily reduced, and the breaking strain and elastic modulus can be easily increased. When the halogen atom content is less than or equal to the above upper limit, synthesis becomes easier.
　ポリアミドイミド樹脂のイミド化率は、好ましくは９０％以上、より好ましくは９３％以上、さらに好ましくは９６％以上であり、通常１００％以下である。光学フィルムの光学特性を高めやすい観点から、イミド化率が上記の下限値以上であることが好ましい。イミド化率は、ポリアミドイミド樹脂中のテトラカルボン酸化合物に由来する構成単位のモル量の２倍の値に対する、ポリアミドイミド樹脂中のイミド結合のモル量の割合を示す。なお、ポリアミドイミド樹脂がトリカルボン酸化合物を含む場合には、ポリアミドイミド樹脂中のテトラカルボン酸化合物に由来する構成単位のモル量の２倍の値と、トリカルボン酸化合物に由来する構成単位のモル量との合計に対する、ポリアミドイミド樹脂中のイミド結合のモル量の割合を示す。また、イミド化率は、ＩＲ法、ＮＭＲ法などにより求めることができる。 The imidization ratio of the polyamide-imide resin is preferably 90% or more, more preferably 93% or more, further preferably 96% or more, and usually 100% or less. From the viewpoint of easily improving the optical characteristics of the optical film, the imidization ratio is preferably at least the above lower limit value. The imidization ratio indicates the ratio of the molar amount of imide bond in the polyamide-imide resin to the value twice the molar amount of the structural unit derived from the tetracarboxylic acid compound in the polyamide-imide resin. When the polyamide-imide resin contains a tricarboxylic acid compound, the value is twice the molar amount of the structural unit derived from the tetracarboxylic acid compound in the polyamide-imide resin, and the molar amount of the structural unit derived from the tricarboxylic acid compound. The ratio of the molar amount of the imide bond in the polyamide-imide resin to the total of the above is shown. The imidization rate can be determined by an IR method, an NMR method, or the like.
　＜ポリアミドイミド樹脂の製造方法＞
　本発明のポリアミドイミド樹脂の製造方法は特に限定されない。本発明の一実施形態においては、後述するテトラカルボン酸化合物、ジカルボン酸化合物及びジアミン化合物を主な原料として製造することができる。より具体的には、ジアミン化合物とテトラカルボン酸化合物とを反応させてポリアミック酸を得る工程、該ポリアミック酸とジカルボン酸とを反応させてポリアミドイミド樹脂前駆体を得る工程、及び該ポリアミドイミド樹脂前駆体をイミド化する工程を含む方法により製造できる。なお、テトラカルボン酸化合物やジカルボン酸化合物の他に、トリカルボン酸化合物を反応させてもよい。 <Manufacturing method of polyamide-imide resin>
The method for producing the polyamide-imide resin of the present invention is not particularly limited. In one embodiment of the present invention, a tetracarboxylic acid compound, a dicarboxylic acid compound and a diamine compound, which will be described later, can be used as main raw materials. More specifically, a step of reacting a diamine compound with a tetracarboxylic acid compound to obtain a polyamic acid, a step of reacting the polyamic acid with a dicarboxylic acid to obtain a polyamide-imide resin precursor, and a step of obtaining the polyamide-imide resin precursor. It can be produced by a method including a step of imidizing the body. In addition to the tetracarboxylic acid compound and the dicarboxylic acid compound, a tricarboxylic acid compound may be reacted.
　式（１）及び式（３０）で表される構成単位は、通常、ジアミン化合物とテトラカルボン酸化合物とから誘導される。式（２）で表される構成単位は、通常、ジアミン化合物とジカルボン酸化合物とから誘導される。式（３１）で表される構成単位は、通常、ジアミン化合物とトリカルボン酸化合物とから誘導される。 The structural units represented by the formulas (1) and (30) are usually derived from a diamine compound and a tetracarboxylic acid compound. The structural unit represented by the formula (2) is usually derived from a diamine compound and a dicarboxylic acid compound. The structural unit represented by the formula (31) is usually derived from a diamine compound and a tricarboxylic acid compound.
　ポリアミドイミド樹脂の製造に用いられるテトラカルボン酸化合物は、少なくとも式（Ｘ）： The tetracarboxylic acid compound used in the production of the polyamide-imide resin has at least the formula (X):
Figure JPOXMLDOC01-appb-C000026
 ［式（Ｘ）中、Ｒ１～Ｒ５、ｍ及びｎは、それぞれ、式（３）中のＲ１～Ｒ５、ｍ及びｎと同じである］
で表される化合物を含むことが好ましい。
Figure JPOXMLDOC01-appb-C000026
 [In formula (X), R 1 to R 5 , m and n are the same as R 1 to R 5 , m and n in formula (3), respectively].
It is preferable to contain the compound represented by.
　式（Ｘ）で表される化合物は、慣用の方法、例えば無水トリメリット酸又はその誘導体と芳香族ジオールとを反応させることにより得てもよいし、市販品を使用してもよい。 The compound represented by the formula (X) may be obtained by a conventional method, for example, by reacting trimellitic anhydride or a derivative thereof with an aromatic diol, or a commercially available product may be used.
　本発明の一実施形態では、ポリアミドイミド樹脂の製造に用いられるテトラカルボン酸化合物は、式（Ｘ）で表される化合物に加えて、さらに式（Ｙ）： In one embodiment of the present invention, the tetracarboxylic acid compound used in the production of the polyamide-imide resin is, in addition to the compound represented by the formula (X), further the formula (Y) :.
Figure JPOXMLDOC01-appb-C000027
 ［式（Ｙ）中、Ｂ、Ｒ７及びｔは、それぞれ、式（５）中のＢ、Ｒ７及びｔと同じである］
で表される化合物を含むことが好ましい。
Figure JPOXMLDOC01-appb-C000027
 [In equation (Y), B, R 7 and t are the same as B, R 7 and t in equation (5), respectively]
It is preferable to contain the compound represented by.
　ポリアミドイミド樹脂の製造（又は合成）に用いられるテトラカルボン酸化合物としては、芳香族テトラカルボン酸二無水物等の芳香族テトラカルボン酸化合物；及び脂肪族テトラカルボン酸二無水物等の脂肪族テトラカルボン酸化合物等が挙げられる。テトラカルボン酸化合物は、単独で用いてもよいし、２種以上を組合せて用いてもよい。テトラカルボン酸化合物は、二無水物の他、酸クロリド化合物等のテトラカルボン酸化合物類縁体であってもよい。 Examples of the tetracarboxylic acid compound used in the production (or synthesis) of the polyamideimide resin include an aromatic tetracarboxylic acid compound such as an aromatic tetracarboxylic dianhydride; and an aliphatic tetra such as an aliphatic tetracarboxylic dianhydride. Examples include carboxylic acid compounds. The tetracarboxylic acid compound may be used alone or in combination of two or more. The tetracarboxylic dian compound may be a tetracarboxylic dian compound analog such as an acid chloride compound in addition to the dianhydride.
　芳香族テトラカルボン酸二無水物の具体例としては、非縮合多環式の芳香族テトラカルボン酸二無水物、単環式の芳香族テトラカルボン酸二無水物及び縮合多環式の芳香族テトラカルボン酸二無水物が挙げられる。非縮合多環式の芳香族テトラカルボン酸二無水物としては、例えば、無水トリメリット酸と２，２’，３，３’，５，５’－ヘキサメチル－４，４’－ビフェノールとのエステル化物（以下、ＴＡＨＭＢＰと記載することがある）、無水トリメリット酸と２，２’，３，３’－テトラメチル－４，４’－ビフェノールとのエステル化物（以下、ＴＡ２３Ｘ－ＢＰと記載することがある）、無水トリメリット酸と３，３’，５，５’－テトラメチル－４，４’－ビフェノールとのエステル化物、４，４’－オキシジフタル酸二無水物、３，３’，４，４’－ベンゾフェノンテトラカルボン酸二無水物、２，２’，３，３’－ベンゾフェノンテトラカルボン酸二無水物、３，３’，４，４’－ビフェニルテトラカルボン酸二無水物、２，２’，３，３’－ビフェニルテトラカルボン酸二無水物、３，３’，４，４’－ジフェニルスルホンテトラカルボン酸二無水物、２，２－ビス（３，４－ジカルボキシフェニル）プロパン二無水物、２，２－ビス（２，３－ジカルボキシフェニル）プロパン二無水物、２，２－ビス（３，４－ジカルボキシフェノキシフェニル）プロパン二無水物、４，４’－（ヘキサフルオロイソプロピリデン）ジフタル酸二無水物（以下、６ＦＤＡと記載することがある）、１，２－ビス（２，３－ジカルボキシフェニル）エタン二無水物、１，１－ビス（２，３－ジカルボキシフェニル）エタン二無水物、１，２－ビス（３，４－ジカルボキシフェニル）エタン二無水物、１，１－ビス（３，４－ジカルボキシフェニル）エタン二無水物、ビス（３，４－ジカルボキシフェニル）メタン二無水物、ビス（２，３－ジカルボキシフェニル）メタン二無水物、４，４’－（ｐ－フェニレンジオキシ）ジフタル酸二無水物、４，４’－（ｍ－フェニレンジオキシ）ジフタル酸二無水物が挙げられる。また、単環式の芳香族テトラカルボン酸二無水物としては、例えば１，２，４，５－ベンゼンテトラカルボン酸二無水物［ピロメリット酸二無水物ともいう（以下、ＰＭＤＡと記載することがある）］が挙げられ、縮合多環式の芳香族テトラカルボン酸二無水物としては、例えば２，３，６，７－ナフタレンテトラカルボン酸二無水物が挙げられる。 Specific examples of the aromatic tetracarboxylic dianhydride include a non-condensed polycyclic aromatic tetracarboxylic dianhydride, a monocyclic aromatic tetracarboxylic dianhydride, and a condensed polycyclic aromatic tetra. Examples include carboxylic dianhydride. Examples of the non-condensed polycyclic aromatic tetracarboxylic dianhydride include an ester of trimellitic anhydride and 2,2', 3,3', 5,5'-hexamethyl-4,4'-biphenol. A product (hereinafter sometimes referred to as TAHMBP), an esterified product of trimellitic anhydride and 2,2', 3,3'-tetramethyl-4,4'-biphenol (hereinafter referred to as TA23X-BP). , 3', 5,5'-tetramethyl-4,4'-biphenol esteride, 4,4'-oxydiphthalic hydride, 3,3', 4,4'-benzophenone tetracarboxylic acid dianhydride, 2,2', 3,3'-benzophenone tetracarboxylic acid dianhydride, 3,3', 4,4'-biphenyltetracarboxylic acid dianhydride, 2 , 2', 3,3'-biphenyltetracarboxylic acid dianhydride, 3,3', 4,4'-diphenylsulfonetetracarboxylic acid dianhydride, 2,2-bis (3,4-dicarboxyphenyl) Propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, 2,2-bis (3,4-dicarboxyphenoxyphenyl) propane dianhydride, 4,4'-( Hexafluoroisopropylidene) diphthalate dianhydride (hereinafter sometimes referred to as 6FDA), 1,2-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (2,3) -Dicarboxyphenyl) ethane dianhydride, 1,2-bis (3,4-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis ( 3,4-dicarboxyphenyl) methane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, 4,4'-(p-phenylenedioxy) diphthalic acid dianhydride, 4,4' -(M-Phenylenedoxy) diphthalate dianhydride can be mentioned. Further, as the monocyclic aromatic tetracarboxylic dianhydride, for example, 1,2,4,5-benzenetetracarboxylic dianhydride [also referred to as pyromellitic dianhydride (hereinafter, referred to as PMDA). There is)], and examples of the fused polycyclic aromatic tetracarboxylic dianhydride include 2,3,6,7-naphthalenetetracarboxylic dianhydride.
　これらの中でも、好ましくはＴＡＨＭＢＰ、ＴＡ２３Ｘ－ＢＰ、無水トリメリット酸と３，３’，５，５’－テトラメチル－４，４’－ビフェノールとのエステル化物、ＰＭＤＡ、４，４’－オキシジフタル酸二無水物、３，３’，４，４’－ベンゾフェノンテトラカルボン酸二無水物、２，２’，３，３’－ベンゾフェノンテトラカルボン酸二無水物、３，３’，４，４’－ビフェニルテトラカルボン酸二無水物、２，２’，３，３’－ビフェニルテトラカルボン酸二無水物、３，３’，４，４’－ジフェニルスルホンテトラカルボン酸二無水物、２，２－ビス（３，４－ジカルボキシフェニル）プロパン二無水物、２，２－ビス（２，３－ジカルボキシフェニル）プロパン二無水物、２，２－ビス（３，４－ジカルボキシフェノキシフェニル）プロパン二無水物、６ＦＤＡ、１，２－ビス（２，３－ジカルボキシフェニル）エタン二無水物、１，１－ビス（２，３－ジカルボキシフェニル）エタン二無水物、１，２－ビス（３，４－ジカルボキシフェニル）エタン二無水物、１，１－ビス（３，４－ジカルボキシフェニル）エタン二無水物、ビス（３，４－ジカルボキシフェニル）メタン二無水物、ビス（２，３－ジカルボキシフェニル）メタン二無水物、４，４’－（ｐ－フェニレンジオキシ）ジフタル酸二無水物、及び４，４’－（ｍ－フェニレンジオキシ）ジフタル酸二無水物が挙げられ、より好ましくは無水トリメリット酸と２，２’，３，３’，５，５’－ヘキサメチル－４，４’－ビフェノールとのエステル化物、無水トリメリット酸と２，２’，３，３’－テトラメチル－４，４’－ビフェノールとのエステル化物、無水トリメリット酸と３，３’，５，５’－テトラメチル－４，４’－ビフェノールとのエステル化物、４，４’－オキシジフタル酸二無水物、３，３’，４，４’－ビフェニルテトラカルボン酸二無水物、２，２’，３，３’－ビフェニルテトラカルボン酸二無水物、６ＦＤＡ、ビス（３，４－ジカルボキシフェニル）メタン二無水物、及び４，４’－（ｐ－フェニレンジオキシ）ジフタル酸二無水物が挙げられる。これらは単独又は２種以上を組合せて使用できる。 Among these, preferably TAHMBP, TA23X-BP, an esterified product of trimellitic anhydride and 3,3', 5,5'-tetramethyl-4,4'-biphenol, PMDA, 4,4'-oxydiphthalic acid. Dianhydride, 3,3', 4,4'-benzophenone tetracarboxylic acid dianhydride, 2,2', 3,3'-benzophenone tetracarboxylic acid dianhydride, 3,3', 4,4'- Biphenyltetracarboxylic acid dianhydride, 2,2', 3,3'-biphenyltetracarboxylic acid dianhydride, 3,3', 4,4'-diphenylsulfonetetracarboxylic acid dianhydride, 2,2-bis (3,4-Dicarboxyphenyl) Propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) Propane dianhydride, 2,2-bis (3,4-dicarboxyphenoxyphenyl) propanedi. Anhydride, 6FDA, 1,2-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,2-bis (3) , 4-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, bis (2, Examples thereof include 3-dicarboxyphenyl) methane dianhydride, 4,4'-(p-phenylenedioxy) diphthalic acid dianhydride, and 4,4'-(m-phenylenedioxy) diphthalic acid dianhydride. , More preferably an esterified product of trimellitic anhydride and 2,2', 3,3', 5,5'-hexamethyl-4,4'-biphenol, trimellitic anhydride and 2,2', 3,3. '-Tetramethyl-4,4'-esterified with biphenol, trimellitic anhydride and 3,3', 5,5'-tetramethyl-4,4'-esterified with biphenol, 4,4'- Oxydiphthalic acid dianhydride, 3,3', 4,4'-biphenyltetracarboxylic acid dianhydride, 2,2', 3,3'-biphenyltetracarboxylic acid dianhydride, 6FDA, bis (3,4- Dicarboxyphenyl) methane dianhydride and 4,4'-(p-phenylenedioxy) diphthalic acid dianhydride. These can be used alone or in combination of two or more.
　脂肪族テトラカルボン酸二無水物としては、環式又は非環式の脂肪族テトラカルボン酸二無水物が挙げられる。環式脂肪族テトラカルボン酸二無水物とは、脂環式炭化水素構造を有するテトラカルボン酸二無水物であり、その具体例としては、１，２，４，５－シクロヘキサンテトラカルボン酸二無水物、１，２，３，４－シクロブタンテトラカルボン酸二無水物、１，２，３，４－シクロペンタンテトラカルボン酸二無水物等のシクロアルカンテトラカルボン酸二無水物、ビシクロ［２．２．２］オクト－７－エン－２，３，５，６－テトラカルボン酸二無水物、ジシクロヘキシル－３，３’，４，４’－テトラカルボン酸二無水物及びこれらの位置異性体が挙げられる。これらは単独で又は２種以上を組合せて用いることができる。非環式脂肪族テトラカルボン酸二無水物の具体例としては、１，２，３，４－ブタンテトラカルボン酸二無水物、及び１，２，３，４－ペンタンテトラカルボン酸二無水物等が挙げられ、これらは単独で又は２種以上を組合せて用いることができる。また、環式脂肪族テトラカルボン酸二無水物及び非環式脂肪族テトラカルボン酸二無水物を組合せて用いてもよい。 Examples of the aliphatic tetracarboxylic dianhydride include cyclic or acyclic aliphatic tetracarboxylic dianhydride. The cyclic aliphatic tetracarboxylic dianhydride is a tetracarboxylic dianhydride having an alicyclic hydrocarbon structure, and specific examples thereof include 1,2,4,5-cyclohexanetetracarboxylic dianhydride. Cycloalkanetetracarboxylic dianhydride such as 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, bicyclo [2.2] .2] Oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, dicyclohexyl-3,3', 4,4'-tetracarboxylic dianhydride and their positional isomers are listed. Be done. These can be used alone or in combination of two or more. Specific examples of the acyclic aliphatic tetracarboxylic dianhydride include 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-pentanetetracarboxylic dianhydride and the like. These can be used alone or in combination of two or more. Further, a cyclic aliphatic tetracarboxylic dianhydride and an acyclic aliphatic tetracarboxylic dianhydride may be used in combination.
　上記テトラカルボン酸二無水物の中でも、光学フィルムの耐力及び透明性を向上しやすい観点から、無水トリメリット酸と２，２’，３，３’，５，５’－ヘキサメチル－４，４’－ビフェノールとのエステル化物、無水トリメリット酸と２，２’，３，３’－テトラメチル－４，４’－ビフェノールとのエステル化物、無水トリメリット酸と３，３’，５，５’－テトラメチル－４，４’－ビフェノールとのエステル化物、ＰＭＤＡ、４，４’－オキシジフタル酸二無水物、３，３’，４，４’－ベンゾフェノンテトラカルボン酸二無水物、３，３’，４，４’－ビフェニルテトラカルボン酸二無水物、２，２’，３，３’－ビフェニルテトラカルボン酸二無水物、３，３’，４，４’－ジフェニルスルホンテトラカルボン酸二無水物、２，２－ビス（３，４－ジカルボキシフェニル）プロパン二無水物、６ＦＤＡ、並びにこれらの混合物が好ましく、無水トリメリット酸と２，２’，３，３’，５，５’－ヘキサメチル－４，４’－ビフェノールとのエステル化物、無水トリメリット酸と２，２’，３，３’－テトラメチル－４，４’－ビフェノールとのエステル化物、無水トリメリット酸と３，３’，５，５’－テトラメチル－４，４’－ビフェノールとのエステル化物、６ＦＤＡ並びにこれらの混合物がより好ましい。 Among the above tetracarboxylic dianhydrides, trimellitic anhydride and 2,2', 3,3', 5,5'-hexamethyl-4,4'from the viewpoint of easily improving the strength and transparency of the optical film. -Esteride with biphenol, trimellitic anhydride and 2,2', 3,3'-tetramethyl-4,4'-esteride with biphenol, trimellitic anhydride and 3,3', 5,5' -Tetramethyl-4,4'-esterified with biphenol, PMDA, 4,4'-oxydiphthalic acid dianhydride, 3,3', 4,4'-benzophenone tetracarboxylic acid dianhydride, 3,3' , 4,4'-biphenyltetracarboxylic acid dianhydride, 2,2', 3,3'-biphenyltetracarboxylic acid dianhydride, 3,3', 4,4'-diphenylsulfonetetracarboxylic acid dianhydride , 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 6FDA, and mixtures thereof are preferred, with trimellitic anhydride and 2,2', 3,3', 5,5'-hexamethyl. Esteride with -4,4'-biphenol, esterified with trimellitic anhydride and 2,2', 3,3'-tetramethyl-4,4'-biphenol, trimellitic anhydride and 3,3' , 5,5'-Tetramethyl-4,4'-esteride with biphenol, 6FDA and mixtures thereof are more preferred.
　ポリアミドイミド樹脂の合成に用いられるジカルボン酸化合物としては、芳香族ジカルボン酸、脂肪族ジカルボン酸及びそれらの類縁の酸クロライド化合物、酸無水物等が挙げられ、２種以上を併用してもよい。具体例としては、テレフタル酸；２，５－ビス（トリフルオロメチル）テレフタル酸；イソフタル酸；２，５－ジメチルテレフタル酸；２，５－ジメトキシテレフタル酸；ナフタレンジカルボン酸；４，４’－ビフェニルジカルボン酸；３，３’－ビフェニルジカルボン酸；２，２’－ビス（トリフルオロメチル）－４，４’－ビフェニルジカルボン酸；炭素数８以下である鎖式炭化水素、のジカルボン酸化合物及び２つの安息香酸が単結合、－ＣＨ２－、－Ｃ（ＣＨ３）２－、－Ｃ（ＣＦ３）２－、－ＳＯ２－又はフェニレン基で連結された化合物並びに、それらの酸クロライド化合物が挙げられる。これらのジカルボン酸化合物の中でも、光学フィルムの耐力及び透明性を向上しやすい観点から、４，４’－オキシビス安息香酸、テレフタル酸、イソフタル酸、２－メトキシテレフタル酸クロライド、２，５－ジメチルテレフタル酸、２，５－ジメトキシテレフタル酸、２，５－ビス（トリフルオロメチル）テレフタル酸、２，２’－ビス（トリフルオロメチル）－４，４’－ビフェニルジカルボン酸及びそれらの酸クロリドが好ましく、２－メトキシテレフタル酸クロライド、４，４’－オキシビス（ベンゾイルクロリド）、２，５－ジメチルテレフタル酸クロライド、２，５－ジメトキシテレフタル酸クロライド、２，５－ビス（トリフルオロメチル）テレフタル酸クロライド、テレフタロイルクロリド（以下、ＴＰＣと記載することがある）、イソフタロイルクロリドがより好ましく、ＴＰＣ、２－メトキシテレフタル酸クロライド、２，５－ジメチルテレフタル酸クロライド、２，５－ジメトキシテレフタル酸クロリドがさらに好ましい。 Examples of the dicarboxylic acid compound used in the synthesis of the polyamide-imide resin include aromatic dicarboxylic acids, aliphatic dicarboxylic acids and their related acid chloride compounds, acid anhydrides, and the like, and two or more of them may be used in combination. Specific examples include terephthalic acid; 2,5-bis (trifluoromethyl) terephthalic acid; isophthalic acid; 2,5-dimethylterephthalic acid; 2,5-dimethoxyterephthalic acid; naphthalenedicarboxylic acid; 4,4'-biphenyl. Dicarboxylic acid; 3,3'-biphenyldicarboxylic acid; 2,2'-bis (trifluoromethyl) -4,4'-biphenyldicarboxylic acid; chain hydrocarbon having 8 or less carbon atoms, a dicarboxylic acid compound and 2 Compounds in which one benzoic acid is single-bonded, -CH 2- , -C (CH 3 ) 2- , -C (CF 3 ) 2- , -SO 2- or a phenylene group, and their acid chloride compounds Can be mentioned. Among these dicarboxylic acid compounds, 4,4'-oxybis benzoic acid, terephthalic acid, isophthalic acid, 2-methoxyterephthalic acid chloride, 2,5-dimethylterephthalic acid, from the viewpoint of easily improving the strength and transparency of the optical film. Acids, 2,5-dimethoxyterephthalic acid, 2,5-bis (trifluoromethyl) terephthalic acid, 2,2'-bis (trifluoromethyl) -4,4'-biphenyldicarboxylic acid and their acid chlorides are preferred. , 2-methoxyterephthalic acid chloride, 4,4'-oxybis (benzoyl chloride), 2,5-dimethylterephthalic acid chloride, 2,5-dimethoxyterephthalic acid chloride, 2,5-bis (trifluoromethyl) terephthalic acid chloride , Terephthaloyl chloride (hereinafter sometimes referred to as TPC), isophthaloyl chloride are more preferable, TPC, 2-methoxyterephthalic acid chloride, 2,5-dimethylterephthalic acid chloride, 2,5-dimethoxyterephthalic acid. Chloride is more preferred.
　なお、上記ポリアミドイミド樹脂は、光学フィルムの各種物性を損なわない範囲で、上記のポリアミドイミド樹脂合成に用いられるテトラカルボン酸化合物に加えて、他のテトラカルボン酸及びトリカルボン酸並びにそれらの無水物及び誘導体を更に反応させたものであってもよい。 In addition to the tetracarboxylic acid compounds used in the synthesis of the polyamide-imide resin, the above-mentioned polyamide-imide resin includes other tetracarboxylic acids and tricarboxylic acids, their anhydrides, and their anhydrides, as long as the various physical properties of the optical film are not impaired. The derivative may be further reacted.
　他のテトラカルボン酸としては、上記テトラカルボン酸化合物の無水物の水付加体が挙げられる。 Examples of other tetracarboxylic acids include water adducts of the anhydrides of the above tetracarboxylic acid compounds.
　トリカルボン酸化合物としては、芳香族トリカルボン酸、脂肪族トリカルボン酸及びそれらの類縁の酸クロリド化合物、酸無水物等が挙げられ、２種以上を組合せて用いてもよい。具体例としては、１，２，４－ベンゼントリカルボン酸の無水物；２，３，６－ナフタレントリカルボン酸－２，３－無水物；フタル酸無水物と安息香酸とが単結合、－Ｏ－、－ＣＨ２－、－Ｃ（ＣＨ３）２－、－Ｃ（ＣＦ３）２－、－ＳＯ２－又はフェニレン基で連結された化合物が挙げられる。 Examples of the tricarboxylic acid compound include aromatic tricarboxylic acids, aliphatic tricarboxylic acids, acid chloride compounds related thereto, acid anhydrides, and the like, and two or more of them may be used in combination. Specific examples include an anhydride of 1,2,4-benzenetricarboxylic acid; 2,3,6-naphthalenetricarboxylic acid-2,3-anhydride; a single bond of phthalic anhydride and benzoic acid, -O- , -CH 2- , -C (CH 3 ) 2- , -C (CF 3 ) 2- , -SO 2- or compounds linked by a phenylene group.
　ポリアミドイミド樹脂の合成に用いられるジアミン化合物としては、例えば、脂肪族ジアミン、芳香族ジアミン及びこれらの混合物が挙げられる。なお、本実施形態において「芳香族ジアミン」とは、アミノ基が芳香環に直接結合しているジアミンを表し、その構造の一部に脂肪族基又はその他の置換基を含んでいてもよい。この芳香環は単環でも縮合環でもよく、ベンゼン環、ナフタレン環、アントラセン環及びフルオレン環等が例示されるが、これらに限定されるわけではない。これらの中でも、好ましくはベンゼン環である。また「脂肪族ジアミン」とは、アミノ基が脂肪族基に直接結合しているジアミンを表し、その構造の一部に芳香環やその他の置換基を含んでいてもよい。 Examples of the diamine compound used for the synthesis of the polyamide-imide resin include aliphatic diamines, aromatic diamines and mixtures thereof. In addition, in this embodiment, "aromatic diamine" represents a diamine in which an amino group is directly bonded to an aromatic ring, and an aliphatic group or other substituent may be contained in a part of the structure. The aromatic ring may be a monocyclic ring or a condensed ring, and examples thereof include, but are not limited to, a benzene ring, a naphthalene ring, an anthracene ring, and a fluorene ring. Among these, a benzene ring is preferable. Further, the "aliphatic diamine" represents a diamine in which an amino group is directly bonded to an aliphatic group, and an aromatic ring or other substituent may be contained as a part of the structure thereof.
　脂肪族ジアミンとしては、例えば、ヘキサメチレンジアミン等の非環式脂肪族ジアミン、並びに１，３－ビス（アミノメチル）シクロヘキサン、１，４－ビス（アミノメチル）シクロヘキサン、ノルボルナンジアミン及び４，４’－ジアミノジシクロヘキシルメタン等の環式脂肪族ジアミン等が挙げられる。これらは単独で又は２種以上を組合せて用いることができる。 Examples of the aliphatic diamine include acyclic aliphatic diamines such as hexamethylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, norbornanediamine and 4,4'. -Cyral aliphatic diamines such as diaminodicyclohexylmethane can be mentioned. These can be used alone or in combination of two or more.
　芳香族ジアミンとしては、例えばｐ－フェニレンジアミン、ｍ－フェニレンジアミン、２，４－トルエンジアミン、ｍ－キシリレンジアミン、ｐ－キシリレンジアミン、１，５－ジアミノナフタレン、２，６－ジアミノナフタレン等の、芳香環を１つ有する芳香族ジアミン、４，４’－ジアミノジフェニルメタン、４，４’－ジアミノジフェニルプロパン、４，４’－ジアミノジフェニルエーテル、３，４’－ジアミノジフェニルエーテル、３，３’－ジアミノジフェニルエーテル、４，４’－ジアミノジフェニルスルホン、３，４’－ジアミノジフェニルスルホン、３，３’－ジアミノジフェニルスルホン、１，４－ビス（４－アミノフェノキシ）ベンゼン、１，３－ビス（４－アミノフェノキシ）ベンゼン、ビス〔４－（４－アミノフェノキシ）フェニル〕スルホン、ビス〔４－（３－アミノフェノキシ）フェニル〕スルホン、２，２－ビス［４－（４－アミノフェノキシ）フェニル］プロパン、２，２－ビス［４－（３－アミノフェノキシ）フェニル］プロパン、２，２’－ジメチルベンジジン、２，２’－ビス（トリフルオロメチル）－４，４’－ジアミノジフェニル（以下、ＴＦＭＢと記載することがある）、４，４’－（ヘキサフルオロプロピリデン）ジアニリン（以下、６ＦＤＡＭと記載することがある）、４，４’－ビス（４－アミノフェノキシ）ビフェニル、９，９－ビス（４－アミノフェニル）フルオレン、９，９－ビス（４－アミノ－３－メチルフェニル）フルオレン、９，９－ビス（４－アミノ－３－クロロフェニル）フルオレン、９，９－ビス（４－アミノ－３－フルオロフェニル）フルオレン等の、芳香環を２つ以上有する芳香族ジアミンが挙げられる。これらは単独又は２種以上を組合せて使用できる。 Examples of the aromatic diamine include p-phenylenediamine, m-phenylenediamine, 2,4-toluenediamine, m-xylylene diamine, p-xylylene diamine, 1,5-diaminonaphthalene, 2,6-diaminonaphthalene and the like. , Aromatic diamine having one aromatic ring, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,3'- Diaminodiphenyl ether, 4,4'-diaminodiphenylsulfone, 3,4′-diaminodiphenylsulfone, 3,3′-diaminodiphenylsulfone, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4) -Aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] Propane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2'-dimethylbenzidine, 2,2'-bis (trifluoromethyl) -4,4'-diaminodiphenyl (hereinafter, TFMB), 4,4'-(hexafluoropropyridene) dianiline (hereinafter sometimes referred to as 6FDAM), 4,4'-bis (4-aminophenoxy) biphenyl, 9,9 -Bis (4-aminophenyl) fluorene, 9,9-bis (4-amino-3-methylphenyl) fluorene, 9,9-bis (4-amino-3-chlorophenyl) fluorene, 9,9-bis (4) Examples thereof include aromatic diamines having two or more aromatic rings, such as -amino-3-fluorophenyl) fluorene. These can be used alone or in combination of two or more.
　芳香族ジアミンとしては、好ましくは４，４’－ジアミノジフェニルメタン、４，４’－ジアミノジフェニルプロパン、４，４’－ジアミノジフェニルエーテル、３，３’－ジアミノジフェニルエーテル、４，４’－ジアミノジフェニルスルホン、３，３’－ジアミノジフェニルスルホン、１，４－ビス（４－アミノフェノキシ）ベンゼン、ビス〔４－（４－アミノフェノキシ）フェニル〕スルホン、ビス〔４－（３－アミノフェノキシ）フェニル〕スルホン、２，２－ビス［４－（４－アミノフェノキシ）フェニル］プロパン、２，２－ビス［４－（３－アミノフェノキシ）フェニル］プロパン、２，２’－ジメチルベンジジン、ＴＦＭＢ、４，４’－ビス（４－アミノフェノキシ）ビフェニルであり、より好ましくは４，４’－ジアミノジフェニルメタン、４，４’－ジアミノジフェニルプロパン、４，４’－ジアミノジフェニルエーテル、４，４’－ジアミノジフェニルスルホン、１，４－ビス（４－アミノフェノキシ）ベンゼン、ビス〔４－（４－アミノフェノキシ）フェニル〕スルホン、２，２－ビス［４－（４－アミノフェノキシ）フェニル］プロパン、２，２’－ジメチルベンジジン、ＴＦＭＢ、６ＦＤＡＭ、４，４’－ビス（４－アミノフェノキシ）ビフェニルである。これらは単独又は２種以上を組合せて使用できる。 As the aromatic diamine, preferably 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenylsulfone, 3,3'-Diaminodiphenyl sulfone, 1,4-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2'-dimethylbenzidine, TFMB, 4,4' -Bis (4-aminophenoxy) biphenyl, more preferably 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylsulfone, 1 , 4-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2'-dimethyl Benzidine, TFMB, 6FDAM, 4,4'-bis (4-aminophenoxy) biphenyl. These can be used alone or in combination of two or more.
　上記ジアミン化合物の中でも、光学フィルムの耐力及び透明性を向上しやすい観点から、２，２’－ジメチルベンジジン、ＴＦＭＢ、４，４’－ビス（４－アミノフェノキシ）ビフェニル、６ＦＤＡＭ及び４，４’－ジアミノジフェニルエーテルからなる群から選ばれる１種以上を用いることがより好ましく、ＴＦＭＢ及び／又は６ＦＤＡＭを用いることがさらに好ましい。 Among the above diamine compounds, 2,2'-dimethylbenzidine, TFMB, 4,4'-bis (4-aminophenoxy) biphenyl, 6FDAM and 4,4'from the viewpoint of easily improving the proof stress and transparency of the optical film. It is more preferable to use one or more selected from the group consisting of -diaminodiphenyl ether, and it is further preferable to use TFMB and / or 6FDAM.
　ポリアミドイミド樹脂の製造において、ジアミン化合物、テトラカルボン酸化合物及びジカルボン酸化合物の使用量は、所望とする樹脂の各構成単位の比率に応じて適宜選択できる。 In the production of the polyamide-imide resin, the amount of the diamine compound, the tetracarboxylic acid compound and the dicarboxylic acid compound used can be appropriately selected according to the ratio of each structural unit of the desired resin.
　本発明の好適な実施形態では、ジアミン化合物の使用量は、テトラカルボン酸化合物及びジカルボン酸化合物の総モル量を１モルとして、好ましくは０．９４モル以上、より好ましくは０．９６モル以上、さらに好ましくは０．９８モル以上、とりわけ好ましくは０．９９モル以上であり、好ましくは１．２０モル以下、より好ましくは１．１０モル以下、さらに好ましくは１．０５モル以下、とりわけ好ましくは１．０２モル以下である。テトラカルボン酸化合物及びジカルボン酸化合物に対するジアミン化合物の使用量が上記の範囲内であると、高分子量のポリアミドイミド樹脂を得やすく、光学フィルムの耐力及び透明性を向上しやすい。 In a preferred embodiment of the present invention, the amount of the diamine compound used is preferably 0.94 mol or more, more preferably 0.96 mol or more, with the total molar amount of the tetracarboxylic acid compound and the dicarboxylic acid compound being 1 mol. It is more preferably 0.98 mol or more, particularly preferably 0.99 mol or more, preferably 1.20 mol or less, more preferably 1.10 mol or less, still more preferably 1.05 mol or less, and particularly preferably 1 It is 0.02 mol or less. When the amount of the diamine compound used with respect to the tetracarboxylic acid compound and the dicarboxylic acid compound is within the above range, it is easy to obtain a high molecular weight polyamide-imide resin, and it is easy to improve the strength and transparency of the optical film.
　ジアミン化合物とテトラカルボン酸化合物との反応温度は、特に限定されず、例えば５～２００℃であってもよく、反応時間も特に限定されず、例えば３０分～７２時間程度であってもよい。本発明の好適な実施形態においては、高分子量のポリアミドイミド樹脂を得やすい観点から、反応温度は、好ましくは５～５０℃、より好ましくは５～４０℃、さらに好ましくは５～２５℃であり、反応時間は、好ましくは３～２４時間、より好ましくは５～２０時間である。 The reaction temperature of the diamine compound and the tetracarboxylic acid compound is not particularly limited and may be, for example, 5 to 200 ° C., and the reaction time is also not particularly limited and may be, for example, about 30 minutes to 72 hours. In a preferred embodiment of the present invention, the reaction temperature is preferably 5 to 50 ° C., more preferably 5 to 40 ° C., still more preferably 5 to 25 ° C. from the viewpoint of easily obtaining a high molecular weight polyamide-imide resin. The reaction time is preferably 3 to 24 hours, more preferably 5 to 20 hours.
　ジアミン化合物とテトラカルボン酸化合物との反応は、溶媒中で行うことが好ましい。溶媒としては、反応に影響を与えない限り特に限定されないが、例えば、水、メタノール、エタノール、エチレングリコール、イソプロピルアルコール、プロピレングリコール、エチレングリコールメチルエーテル、エチレングリコールブチルエーテル、１－メトキシ－２－プロパノール、２－ブトキシエタノール、プロピレングリコールモノメチルエーテル等のアルコール系溶媒；酢酸エチル、酢酸ブチル、エチレングリコールメチルエーテルアセテート、γ－ブチロラクトン、γ－バレロラクトン、プロピレングリコールメチルエーテルアセテート、乳酸エチル等のエステル系溶媒；アセトン、メチルエチルケトン、シクロペンタノン、シクロヘキサノン、２－ヘプタノン、メチルイソブチルケトン等のケトン系溶媒；ペンタン、ヘキサン、ヘプタン等の脂肪族炭化水素溶媒；エチルシクロヘキサン等の脂環式炭化水素溶媒；トルエン、キシレン等の芳香族炭化水素溶媒；アセトニトリル等のニトリル系溶媒；テトラヒドロフラン及びジメトキシエタン等のエーテル系溶媒；クロロホルム及びクロロベンゼン等の塩素含有溶媒；Ｎ，Ｎ－ジメチルアセトアミド（以下、ＤＭＡｃと記載することがある）、Ｎ，Ｎ－ジメチルホルムアミド（以下、ＤＭＦと記載することがある）等のアミド系溶媒；ジメチルスルホン、ジメチルスルホキシド、スルホラン等の含硫黄系溶媒；エチレンカーボネート、プロピレンカーボネート等のカーボネート系溶媒；及びそれらの組合せなどが挙げられる。これらの中でも、溶解性の観点から、アミド系溶媒を好適に使用できる。 The reaction between the diamine compound and the tetracarboxylic acid compound is preferably carried out in a solvent. The solvent is not particularly limited as long as it does not affect the reaction, and is, for example, water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, 1-methoxy-2-propanol, and the like. Alcohol-based solvents such as 2-butoxyethanol and propylene glycol monomethyl ether; ester-based solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, γ-valerolactone, propylene glycol methyl ether acetate and ethyl lactate; Ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; alicyclic hydrocarbon solvents such as ethyl cyclohexane; toluene and xylene Aromatic hydrocarbon solvents such as; nitrile solvents such as acetonitrile; ether solvents such as tetrahydrofuran and dimethoxyethane; chlorine-containing solvents such as chloroform and chlorobenzene; N, N-dimethylacetamide (hereinafter, may be referred to as DMAc). ), N, N-dimethylformamide (hereinafter, may be referred to as DMF) and other amide solvents; sulfur-containing solvents such as dimethyl sulfone, dimethyl sulfoxide and sulfolane; carbonate solvents such as ethylene carbonate and propylene carbonate; And combinations thereof. Among these, an amide-based solvent can be preferably used from the viewpoint of solubility.
　本発明の好適な実施形態においては、反応に使用する溶媒は、高分子量のポリアミドイミド樹脂を得やすい観点から、水分量７００ｐｐｍ以下まで厳密に脱水した溶媒であることが好ましい。 In a preferred embodiment of the present invention, the solvent used in the reaction is preferably a solvent that has been strictly dehydrated to a water content of 700 ppm or less from the viewpoint of easily obtaining a high molecular weight polyamide-imide resin.
　ジアミン化合物とテトラカルボン酸化合物との反応は、必要に応じて、窒素やアルゴンなどの不活性雰囲気又は減圧の条件下において行ってもよく、高分子量のポリアミドイミド樹脂を得やすい観点から、前記と同じ不活性雰囲気下、厳密に制御された脱水溶媒中で撹拌しながら行うことが好ましい。 The reaction between the diamine compound and the tetracarboxylic acid compound may be carried out under an inert atmosphere such as nitrogen or argon or under reduced pressure, if necessary, and from the viewpoint of easily obtaining a high-molecular-weight polyamide-imide resin, the above-mentioned reaction is carried out. It is preferably carried out with stirring in a tightly controlled dehydration solvent under the same inert atmosphere.
　ポリアミック酸とジカルボン酸との製造条件は、ジアミン化合物とテトラカルボン酸化合物との反応における製造条件から適宜選択すればよい。 The production conditions of the polyamic acid and the dicarboxylic acid may be appropriately selected from the production conditions in the reaction of the diamine compound and the tetracarboxylic acid compound.
　イミド化工程で使用するイミド化触媒としては、例えばトリプロピルアミン、ジブチルプロピルアミン、エチルジブチルアミン等の脂肪族アミン；Ｎ－エチルピペリジン、Ｎ－プロピルピペリジン、Ｎ－ブチルピロリジン、Ｎ－ブチルピペリジン、及びＮ－プロピルヘキサヒドロアゼピン等の脂環式アミン（単環式）；アザビシクロ［２．２．１］ヘプタン、アザビシクロ［３．２．１］オクタン、アザビシクロ［２．２．２］オクタン、及びアザビシクロ［３．２．２］ノナン等の脂環式アミン（多環式）；並びにピリジン、２－メチルピリジン（２－ピコリン）、３－メチルピリジン（３－ピコリン）、４－メチルピリジン（４－ピコリン）、２－エチルピリジン、３－エチルピリジン、４－エチルピリジン、２，４－ジメチルピリジン、２，４，６－トリメチルピリジン、３，４－シクロペンテノピリジン、５，６，７，８－テトラヒドロイソキノリン、及びイソキノリン等の芳香族アミンが挙げられる。また、イミド化反応を促進しやすい観点から、イミド化触媒とともに、酸無水物を用いることが好ましい。酸無水物は、イミド化反応に用いられる慣用の酸無水物等が挙げられ、その具体例としては、無水酢酸、無水プロピオン酸、無水酪酸等の脂肪族酸無水物、フタル酸等の芳香族酸無水物などが挙げられる。 Examples of the imidization catalyst used in the imidization step include aliphatic amines such as tripropylamine, dibutylpropylamine and ethyldibutylamine; N-ethylpiperidin, N-propylpiperidin, N-butylpyrrolidin, N-butylpiperidine, etc. And alicyclic amines such as N-propylhexahydroazepine (monocyclic); azabicyclo [2.2.1] heptane, azabicyclo [3.2.1] octane, azabicyclo [2.2.2] octane, and Alicyclic amines (polycyclic) such as azabicyclo [3.2.2] nonane; and pyridine, 2-methylpyridine (2-picolin), 3-methylpyridine (3-picolin), 4-methylpyridine (4). -Picolin), 2-ethylpyridine, 3-ethylpyridine, 4-ethylpyridine, 2,4-dimethylpyridine, 2,4,6-trimethylpyridine, 3,4-cyclopentenopyridine, 5,6,7, Examples include 8-tetrahydroisoquinoline and aromatic amines such as isoquinolin. Further, from the viewpoint of easily promoting the imidization reaction, it is preferable to use an acid anhydride together with the imidization catalyst. Examples of the acid anhydride include conventional acid anhydrides used in the imidization reaction, and specific examples thereof include acetic anhydride, propionic anhydride, butyric anhydride and other aliphatic acid anhydrides, and phthalic acid and other aromatics. Acid anhydride and the like can be mentioned.
　本発明の好適な実施形態では、イミド化工程を段階的に行い、最適な反応温度まで、昇温することが好ましい。段階的にイミド化することにより、樹脂の分解を抑制し、高分子量のポリアミドイミド樹脂を得やすい。段階的に行うイミド化工程の昇温させる反応温度は、好ましくは４０～８５℃であり、より好ましくは４５～８０℃である。反応温度が前記の範囲にあると、十分にイミド化反応が進行する傾向があり、またＭｗが十分に上がる傾向がある。その反応時間は、好ましくは３０分～１０時間、より好ましくは３０分～５時間である。反応時間が前記の範囲内にあると、樹脂の分解が生じてＭｗが低下することを抑制しやすく、また、イミド化率が低下してその後の工程で低分子量化することを抑制しやすい。このように既述の合成条件に加えて、イミド化工程を制御することで、高分子量の樹脂を得ることができる。 In a preferred embodiment of the present invention, it is preferable to carry out the imidization step stepwise and raise the temperature to the optimum reaction temperature. By stepwise imidizing, decomposition of the resin is suppressed, and a high molecular weight polyamide-imide resin can be easily obtained. The reaction temperature for raising the temperature in the stepwise imidization step is preferably 40 to 85 ° C, more preferably 45 to 80 ° C. When the reaction temperature is in the above range, the imidization reaction tends to proceed sufficiently, and Mw tends to rise sufficiently. The reaction time is preferably 30 minutes to 10 hours, more preferably 30 minutes to 5 hours. When the reaction time is within the above range, it is easy to suppress the decomposition of the resin and the decrease in Mw, and it is easy to suppress the decrease in the imidization rate and the reduction in the molecular weight in the subsequent steps. By controlling the imidization step in addition to the above-mentioned synthesis conditions in this way, a high molecular weight resin can be obtained.
　ポリアミドイミド樹脂は、慣用の方法、例えば、濾過、濃縮、抽出、晶析、再結晶、カラムクロマトグラフィーなどの分離手段や、これらを組合せた分離手段により分離精製して、単離してもよく、好ましい形態では、樹脂を含む反応液に、多量のメタノール等のアルコールを加え、樹脂を析出させ、濃縮、濾過、乾燥等を行うことにより単離することができる。 The polyamide-imide resin may be isolated by separating and purifying it by a conventional method, for example, a separation means such as filtration, concentration, extraction, crystallization, recrystallization, or column chromatography, or a separation means combining these. In a preferred form, the resin can be isolated by adding a large amount of alcohol such as methanol to the reaction solution containing the resin, precipitating the resin, and performing concentration, filtration, drying, and the like.
　本発明は、本発明のポリアミドイミド樹脂を含む光学フィルムを包含する。本発明の光学フィルムは、ポリアミドイミド樹脂を含む。本発明の光学フィルムは、１種類のポリアミドイミド樹脂を含んでいてもよいし、２種以上のポリアミドイミド樹脂を含んでいてもよい。本発明の光学フィルム中におけるポリアミドイミド樹脂の含有量は、光学フィルム１００質量部に対して、好ましくは１０質量部以上、より好ましくは３０質量部以上、さらに好ましくは５０質量部以上であり、好ましくは９９．５質量部以下、より好ましくは９５質量部以下である。ポリアミドイミド樹脂の含有量が上記範囲内であると、光学フィルムの光学特性、耐衝撃性及び弾性率、並びに耐力を向上させやすい。 The present invention includes an optical film containing the polyamide-imide resin of the present invention. The optical film of the present invention contains a polyamide-imide resin. The optical film of the present invention may contain one kind of polyamide-imide resin, or may contain two or more kinds of polyamide-imide resins. The content of the polyamide-imide resin in the optical film of the present invention is preferably 10 parts by mass or more, more preferably 30 parts by mass or more, still more preferably 50 parts by mass or more, and preferably 50 parts by mass or more, based on 100 parts by mass of the optical film. Is 99.5 parts by mass or less, more preferably 95 parts by mass or less. When the content of the polyamide-imide resin is within the above range, the optical properties, impact resistance, elastic modulus, and proof stress of the optical film can be easily improved.
　本発明の光学フィルムは、前記ポリアミドイミド樹脂を含むため、高耐力と高い透明性とを両立できる。そのため、本発明のポリアミドイミド樹脂及び光学フィルムはフレキシブル表示装置の材料等に好適に利用できる。なお、本明細書において、透明性は、全光線透過率及びヘーズなどで評価することができ、透明性が高まる又は向上するとは、全光線透過率が高いこと、及び／又は、へーズが低いこと、及び／又は、ＹＩ値が低いことを意味する。 Since the optical film of the present invention contains the polyamide-imide resin, both high yield strength and high transparency can be achieved at the same time. Therefore, the polyamide-imide resin and the optical film of the present invention can be suitably used as materials for flexible display devices. In addition, in this specification, transparency can be evaluated by total light transmittance and haze, and when transparency is increased or improved, total light transmittance is high and / or haze is low. That and / or means that the YI value is low.
　本発明の光学フィルムは、高い耐力を示すことができる。該光学フィルムの耐力は、好ましくは９０ＭＰａ以上、より好ましくは９５Ｍｐａ以上、さらに好ましくは１００ＭＰａ以上、とりわけ好ましくは１０５ＭＰａ以上であり、通常、２００ＭＰａ以下である。耐力が上記下限値以上であると、光学フィルムの耐屈曲性、特に耐折性を向上しやすい。光学フィルムの屈曲に対する耐性に影響し得る物性値として、弾性率等の種々の物性値が検討されてはいるが、本発明者らの検討によれば、単に弾性率を向上させるのみでは十分な耐折性は達成できない場合があることがわかった。そこで、耐折性のさらなる向上を目指し、本発明者らが種々の物性値について検討した結果、光学フィルムの耐力を高めることによって、耐折性を十分に高めることができることがわかった。なお、耐力は引張試験機で測定でき、例えば、実施例に記載の方法により測定できる。 The optical film of the present invention can exhibit high yield strength. The proof stress of the optical film is preferably 90 MPa or more, more preferably 95 MPa or more, further preferably 100 MPa or more, particularly preferably 105 MPa or more, and usually 200 MPa or less. When the proof stress is at least the above lower limit value, it is easy to improve the bending resistance, particularly the folding resistance of the optical film. Various physical property values such as elastic modulus have been studied as physical property values that can affect the resistance to bending of the optical film, but according to the studies by the present inventors, it is sufficient to simply improve the elastic modulus. It has been found that folding resistance may not be achieved. Therefore, as a result of examining various physical property values with the aim of further improving the fold resistance, it was found that the fold resistance can be sufficiently increased by increasing the proof stress of the optical film. The proof stress can be measured with a tensile tester, for example, by the method described in Examples.
　本発明の好適な実施形態において、本発明の光学フィルムの全光線透過率、好ましくは厚さ４０μｍにおける全光線透過率は、好ましくは８５％以上、より好ましくは８８％以上、さらに好ましくは８８％を超える、さらにより好ましくは９０％以上、とりわけ好ましくは９１％以上である。全光線透過率が上記の下限値以上であると、光学フィルムの透明性を向上でき、例えば表示装置の前面板等に使用した場合に、高い視認性を発現できる。全光線透過率の上限は通常１００％以下である。本発明の光学フィルムは通常、高い全光線透過率を示すので、例えば、透過率の低いフィルムを用いた場合と比べて、一定の明るさを得るために必要な表示素子等の発光強度を抑えることが可能となる。このため、消費電力を削減することができる。例えば、本発明の光学フィルムを表示装置に組みこむ場合、バックライトの光量を減らしても明るい表示を得られる傾向があり、エネルギーの節約に貢献できる。また、全光線透過率は、ＪＩＳ　Ｋ　７１０５：１９８１に準拠してヘーズコンピュータを用いて測定でき、例えば実施例に記載の方法により測定できる。また、本明細書において、全光線透過率は、本発明の光学フィルムの厚さの範囲における全光線透過率とすることもできる。全光線透過率は、後述する光学フィルムの厚さの範囲における全光線透過率であってよい。なお、本明細書において、光学フィルムが光学特性に優れるとは、全光線透過率が高いこと、及び／又は、へーズが低いこと、及び／又は、ＹＩ値が低いことを意味し、透明性が高まる又は向上すると同じ意味で使用することがある。 In a preferred embodiment of the present invention, the total light transmittance of the optical film of the present invention, preferably the total light transmittance at a thickness of 40 μm, is preferably 85% or more, more preferably 88% or more, still more preferably 88%. More than, even more preferably 90% or more, and particularly preferably 91% or more. When the total light transmittance is at least the above lower limit value, the transparency of the optical film can be improved, and high visibility can be exhibited when used for, for example, the front plate of a display device. The upper limit of the total light transmittance is usually 100% or less. Since the optical film of the present invention usually exhibits a high total light transmittance, the emission intensity of a display element or the like required to obtain a constant brightness is suppressed as compared with the case where a film having a low transmittance is used, for example. It becomes possible. Therefore, power consumption can be reduced. For example, when the optical film of the present invention is incorporated into a display device, a bright display tends to be obtained even if the amount of light from the backlight is reduced, which can contribute to energy saving. Further, the total light transmittance can be measured by using a haze computer in accordance with JIS K 7105: 1981, and can be measured by, for example, the method described in Examples. Further, in the present specification, the total light transmittance may be the total light transmittance in the range of the thickness of the optical film of the present invention. The total light transmittance may be the total light transmittance in the range of the thickness of the optical film described later. In the present specification, when the optical film is excellent in optical characteristics, it means that the total light transmittance is high and / or the haze is low and / or the YI value is low, and the transparency is high. May be used interchangeably as it increases or improves.
　本発明の好適な実施形態において、本発明の光学フィルムのヘーズ、好ましくは厚さ４０μｍにおけるヘーズは、好ましくは２．０％以下、より好ましくは１．５％以下、さらに好ましくは１．０％以下、さらにより好ましくは０．８％以下、とりわけ好ましくは０．５％以下、とりわけより好ましくは０．３％以下であり、通常、０％以上である。光学フィルムのヘーズが上記の上限値以下であると、光学フィルムの透明性を向上でき、例えば表示装置の前面板等に使用した場合に、高い視認性を発現できる。なお、ヘーズは、ＪＩＳ　Ｋ　７１３６：２０００に準拠して、ヘーズコンピュータ等を用いて測定でき、例えば実施例に記載の方法により測定できる。また、本明細書において、ヘーズは、後述する光学フィルムの厚さの範囲におけるであってよい。 In a preferred embodiment of the present invention, the haze of the optical film of the present invention, preferably at a thickness of 40 μm, is preferably 2.0% or less, more preferably 1.5% or less, still more preferably 1.0%. Below, it is even more preferably 0.8% or less, particularly preferably 0.5% or less, particularly more preferably 0.3% or less, and usually 0% or more. When the haze of the optical film is not more than the above upper limit value, the transparency of the optical film can be improved, and high visibility can be exhibited when used for, for example, the front plate of a display device. The haze can be measured using a haze computer or the like in accordance with JIS K 7136: 2000, and can be measured by, for example, the method described in Examples. Further, in the present specification, the haze may be in the range of the thickness of the optical film described later.
　本発明の好適な実施形態において、本発明の光学フィルムのＹＩ値は、好ましくは３．０未満、より好ましくは２．８以下、さらに好ましくは２．５以下である。光学フィルムのＹＩ値が上記の上限値以下であると、光学フィルムの透明性を向上でき、表示装置の前面板等に使用した場合に、高い視認性を発現できる。また黄色度は通常－５以上であり、好ましくは－２以上である。なお、ＹＩ値は紫外可視近赤外分光光度計を用いて３００～８００ｎｍの光に対する透過率測定を行い、３刺激値（Ｘ、Ｙ、Ｚ）を求め、ＹＩ＝１００×（１．２７６９Ｘ－１．０５９２Ｚ）／Ｙの式に基づいて算出できる。例えば実施例に記載の方法により算出できる。 In a preferred embodiment of the present invention, the YI value of the optical film of the present invention is preferably less than 3.0, more preferably 2.8 or less, still more preferably 2.5 or less. When the YI value of the optical film is not more than the above upper limit value, the transparency of the optical film can be improved, and high visibility can be exhibited when used for the front plate of a display device or the like. The yellowness is usually −5 or higher, preferably −2 or higher. The YI value was measured by measuring the transmittance of light at 300 to 800 nm using an ultraviolet-visible near-infrared spectrophotometer, and the tristimulus values (X, Y, Z) were obtained, and YI = 100 × (1.2769X-). It can be calculated based on the formula of 1.0592Z) / Y. For example, it can be calculated by the method described in Examples.
　本発明の好適な実施形態において、本発明の光学フィルムの弾性率は、好ましくは５．０ＧＰａ以上、より好ましくは５．５ＧＰａ以上、さらに好ましくは６．０ＧＰａ以上であり、通常１５ＧＰａ以下である。弾性率が上記の下限値以上であると、光学フィルムの変形を抑制しやすく、かつ耐久性を向上しやすい。弾性率は、引張試験機を用いて測定でき、例えば実施例に記載の方法により測定できる。なお、弾性率は２５℃における値である。 In a preferred embodiment of the present invention, the elastic modulus of the optical film of the present invention is preferably 5.0 GPa or more, more preferably 5.5 GPa or more, still more preferably 6.0 GPa or more, and usually 15 GPa or less. When the elastic modulus is at least the above lower limit value, it is easy to suppress the deformation of the optical film and it is easy to improve the durability. The elastic modulus can be measured using a tensile tester, for example, by the method described in Examples. The elastic modulus is a value at 25 ° C.
　本発明の好適な実施形態において、本発明の光学フィルムのＡＳＴＭ規格Ｄ２１７６－１６に準拠したＭＩＴ耐折疲労試験における耐折回数は、好ましくは８０，０００回以上、より好ましくは１００，０００回以上、さらに好ましくは２００，０００回以上、とりわけ好ましくは２５０，０００回以上である。耐折回数が上記の下限値以上であると、繰り返し折り曲げてもクラックや割れ等の発生を有効に抑制できる。なお、ＭＩＴ耐折疲労試験は、ＭＩＴ耐折疲労試験機を用いて測定でき、例えば実施例に記載の方法により測定できる。 In a preferred embodiment of the present invention, the number of times of folding of the optical film of the present invention in the MIT folding fatigue test conforming to ASTM standard D2176-16 is preferably 80,000 times or more, more preferably 100,000 times or more. More preferably 200,000 times or more, and particularly preferably 250,000 times or more. When the number of times of folding resistance is equal to or more than the above lower limit value, the occurrence of cracks and cracks can be effectively suppressed even when repeatedly bent. The MIT fold resistance fatigue test can be measured using a MIT fold resistance fatigue tester, for example, by the method described in Examples.
　全光線透過率及びヘーズは、光学フィルムの厚さに応じて変化し、厚さが大きくなるほど、全光線透過率は低下し、ヘーズは高くなる。すなわち、厚さが大きいフィルムにおいて、全光線透過率が高く、かつヘーズが低い光学フィルムを作製することは困難である。
　一方、本発明の好適な実施形態において、本発明の光学フィルムは、高水準の透明性を有するため、厚さが比較的大きくても、高い全光線透過率及び低いヘーズを示すことができる。そのため、本発明の光学フィルムの厚さは、好ましくは１０μｍ以上、より好ましくは１５μｍ以上、さらに好ましくは２０μｍ以上、さらにより好ましくは３０μｍ以上、とりわけ好ましくは３５μｍ以上、とりわけより好ましくは４０μｍ以上であり、好ましくは１００μｍ以下、より好ましくは８０μｍ以下、さらに好ましくは６０μｍ以下である。光学フィルムの厚さは、厚さ計などで測定でき、例えば実施例に記載の方法により測定できる。 The total light transmittance and the haze change according to the thickness of the optical film, and the larger the thickness, the lower the total light transmittance and the higher the haze. That is, it is difficult to produce an optical film having a high total light transmittance and a low haze in a film having a large thickness.
On the other hand, in a preferred embodiment of the present invention, the optical film of the present invention has a high level of transparency and thus can exhibit high total light transmittance and low haze even if the thickness is relatively large. Therefore, the thickness of the optical film of the present invention is preferably 10 μm or more, more preferably 15 μm or more, still more preferably 20 μm or more, still more preferably 30 μm or more, particularly preferably 35 μm or more, and particularly preferably 40 μm or more. It is preferably 100 μm or less, more preferably 80 μm or less, and further preferably 60 μm or less. The thickness of the optical film can be measured with a thickness gauge or the like, for example, by the method described in Examples.
　＜添加剤＞
　本発明の光学フィルムは、ポリアミドイミド樹脂に加えて、少なくとも１種のフィラーを含んでよい。フィラーとしては、例えば有機粒子、無機粒子などが挙げられ、好ましくは無機粒子が挙げられる。無機粒子としては、シリカ、ジルコニア、アルミナ、チタニア、酸化亜鉛、酸化ゲルマニウム、酸化インジウム、酸化スズ、インジウムスズ酸化物（ＩＴＯ）、酸化アンチモン、酸化セリウム等の金属酸化物粒子、フッ化マグネシウム、フッ化ナトリウム等の金属フッ化物粒子などが挙げられ、これらの中でも、光学フィルムの耐力、弾性率及び透明性を向上しやすい観点から、好ましくはシリカ粒子、ジルコニア粒子、アルミナ粒子が挙げられ、より好ましくはシリカ粒子が挙げられる。これらのフィラーは単独又は２種以上を組合せて使用できる。 <Additives>
The optical film of the present invention may contain at least one filler in addition to the polyamide-imide resin. Examples of the filler include organic particles and inorganic particles, and preferably inorganic particles. Examples of the inorganic particles include metal oxide particles such as silica, zirconia, alumina, titania, zinc oxide, germanium oxide, indium oxide, tin oxide, indium tin oxide (ITO), antimony oxide, and cerium oxide, magnesium fluoride, and fluoride. Examples thereof include metal fluoride particles such as sodium chemicals, and among these, silica particles, zirconia particles, and alumina particles are preferable from the viewpoint of easily improving the strength, elasticity, and transparency of the optical film, and more preferably. Examples include silica particles. These fillers can be used alone or in combination of two or more.
　フィラー、好ましくはシリカ粒子の平均一次粒子径は、通常１ｎｍ以上、好ましくは５ｎｍ以上、より好ましくは１０ｎｍ以上、さらに好ましくは１５ｎｍ以上、とりわけ好ましくは２０ｎｍ以上であり、好ましくは１００ｎｍ以下、より好ましくは９０ｎｍ以下、さらに好ましくは８０ｎｍ以下、さらにより好ましくは７０ｎｍ以下、とりわけ好ましくは６０ｎｍ以下、とりわけより好ましくは５０ｎｍ以下、とりわけさらに好ましくは４０ｎｍ以下である。シリカ粒子の平均一次粒子径が上記範囲内であると、光学フィルムの耐力、弾性率及び透明性を向上しやすい。また、シリカ粒子の凝集を抑制し、得られる光学フィルムの透明性を向上しやすい。フィラーの平均一次粒子径は、ＢＥＴ法により測定できる。なお、透過型電子顕微鏡や走査型電子顕微鏡の画像解析により、平均一次粒子径を測定してもよい。 The average primary particle size of the filler, preferably silica particles, is usually 1 nm or more, preferably 5 nm or more, more preferably 10 nm or more, still more preferably 15 nm or more, particularly preferably 20 nm or more, preferably 100 nm or less, more preferably. It is 90 nm or less, more preferably 80 nm or less, even more preferably 70 nm or less, particularly preferably 60 nm or less, particularly more preferably 50 nm or less, and particularly preferably 40 nm or less. When the average primary particle size of the silica particles is within the above range, the strength, elastic modulus and transparency of the optical film can be easily improved. In addition, it is easy to suppress the aggregation of silica particles and improve the transparency of the obtained optical film. The average primary particle size of the filler can be measured by the BET method. The average primary particle size may be measured by image analysis of a transmission electron microscope or a scanning electron microscope.
　本発明の光学フィルムがフィラー、好ましくはシリカ粒子を含有する場合、フィラーの含有量は、光学フィルムの質量に対して、通常０．１質量％以上、好ましくは１質量％以上、より好ましくは５質量％以上、さらに好ましくは１０質量％以上、さらによりに好ましくは２０質量％以上、とりわけ好ましくは３０質量％以上であり、好ましくは６０質量％以下である。フィラーの含有量が上記の下限値以上であると、光学フィルムの耐力、弾性率及び透明性を向上しやすい。また、フィラーの含有量が上記の上限値以下であると、光学フィルムの光学特性を向上しやすい。 When the optical film of the present invention contains a filler, preferably silica particles, the content of the filler is usually 0.1% by mass or more, preferably 1% by mass or more, more preferably 5 with respect to the mass of the optical film. It is mass% or more, more preferably 10% by mass or more, even more preferably 20% by mass or more, particularly preferably 30% by mass or more, and preferably 60% by mass or less. When the filler content is at least the above lower limit value, the proof stress, elastic modulus and transparency of the optical film are likely to be improved. Further, when the content of the filler is not more than the above upper limit value, the optical characteristics of the optical film can be easily improved.
　本発明の光学フィルムは、紫外線吸収剤をさらに含有してもよい。紫外線吸収剤は、樹脂材料の分野で紫外線吸収剤として通常用いられているものから、適宜選択することができる。紫外線吸収剤は、４００ｎｍ以下の波長の光を吸収する化合物を含んでいてもよい。紫外線吸収剤としては、例えば、ベンゾフェノン系化合物、サリシレート系化合物、ベンゾトリアゾール系化合物、及びトリアジン系化合物からなる群より選ばれる少なくとも１種の化合物が挙げられる。紫外線吸収剤は単独又は二種以上を組合せて使用できる。光学フィルムが紫外線吸収剤を含有することにより、樹脂の劣化が抑制されるため、光学フィルムを画像表示装置等に適用した場合に視認性を高めることができる。本明細書において、「系化合物」とは、当該「系化合物」が付される化合物の誘導体を指す。例えば、「ベンゾフェノン系化合物」とは、母体骨格としてのベンゾフェノンと、ベンゾフェノンに結合している置換基とを有する化合物を指す。 The optical film of the present invention may further contain an ultraviolet absorber. The ultraviolet absorber can be appropriately selected from those usually used as an ultraviolet absorber in the field of resin materials. The ultraviolet absorber may contain a compound that absorbs light having a wavelength of 400 nm or less. Examples of the ultraviolet absorber include at least one compound selected from the group consisting of benzophenone compounds, salicylate compounds, benzotriazole compounds, and triazine compounds. The UV absorber can be used alone or in combination of two or more. Since the optical film contains an ultraviolet absorber, deterioration of the resin is suppressed, so that visibility can be improved when the optical film is applied to an image display device or the like. As used herein, the term "system compound" refers to a derivative of a compound to which the "system compound" is attached. For example, the "benzophenone-based compound" refers to a compound having benzophenone as a maternal skeleton and a substituent attached to benzophenone.
　光学フィルムが紫外線吸収剤を含有する場合、紫外線吸収剤の含有量は、光学フィルムの質量に対して、好ましくは１質量％以上、より好ましくは２質量％以上、さらに好ましくは３質量％以上であり、好ましくは１０質量％以下、より好ましくは８質量％以下、さらに好ましくは６質量％以下である。好適な含有量は用いる紫外線吸収剤により異なるが、４００ｎｍの光線透過率が２０～６０％程度になるように紫外線吸収剤の含有量を調節すると、光学フィルムの耐光性が高められるとともに、透明性を高めやすい。 When the optical film contains an ultraviolet absorber, the content of the ultraviolet absorber is preferably 1% by mass or more, more preferably 2% by mass or more, still more preferably 3% by mass or more, based on the mass of the optical film. Yes, preferably 10% by mass or less, more preferably 8% by mass or less, still more preferably 6% by mass or less. The suitable content varies depending on the UV absorber used, but if the content of the UV absorber is adjusted so that the light transmittance at 400 nm is about 20 to 60%, the light resistance of the optical film is enhanced and the transparency is improved. Easy to increase.
　本発明の光学フィルムは、フィラー及び紫外線吸収剤以外の他の添加剤をさらに含有していてもよい。他の添加剤としては、例えば、酸化防止剤、離型剤、安定剤、ブルーイング剤、難燃剤、ｐＨ調整剤、シリカ分散剤、滑剤、増粘剤、及びレベリング剤等が挙げられる。他の添加剤を含有する場合、その含有量は、光学フィルムの質量に対して、好ましくは０．００１～２０質量％、より好ましくは０．０１～１５質量％、さらに好ましくは０．１～１０質量％であってよい。 The optical film of the present invention may further contain additives other than the filler and the ultraviolet absorber. Other additives include, for example, antioxidants, mold release agents, stabilizers, bluing agents, flame retardants, pH regulators, silica dispersants, lubricants, thickeners, leveling agents and the like. When other additives are contained, the content thereof is preferably 0.001 to 20% by mass, more preferably 0.01 to 15% by mass, still more preferably 0.1 to 100% by mass, based on the mass of the optical film. It may be 10% by mass.
　本発明の光学フィルムの用途は特に限定されず、種々の用途に使用してよい。本発明の光学フィルムは、単層であっても、積層体であってもよく、本発明の光学フィルムをそのまま使用してもよいし、さらに他のフィルムとの積層体として使用してもよい。なお、光学フィルムが積層体である場合、光学フィルムの片面又は両面に積層された全ての層を含めて光学フィルムと称する。 The use of the optical film of the present invention is not particularly limited, and it may be used for various purposes. The optical film of the present invention may be a single layer or a laminated body, the optical film of the present invention may be used as it is, or may be used as a laminated body with another film. .. When the optical film is a laminated body, it is referred to as an optical film including all the layers laminated on one side or both sides of the optical film.
　本発明の光学フィルムが積層体である場合、光学フィルムの少なくとも一方の面に１以上の機能層を有することが好ましい。機能層としては、例えばハードコート層、プライマー層、ガスバリア層、紫外線吸収層、粘着層、色相調整層、屈折率調整層などが挙げられる。機能層は単独又は二種以上組合せて使用できる。 When the optical film of the present invention is a laminated body, it is preferable to have one or more functional layers on at least one surface of the optical film. Examples of the functional layer include a hard coat layer, a primer layer, a gas barrier layer, an ultraviolet absorbing layer, an adhesive layer, a hue adjusting layer, and a refractive index adjusting layer. The functional layer can be used alone or in combination of two or more.
　ハードコート層の厚さは特に限定されず、例えば、２～１００μｍであってもよい。前記ハードコート層の厚さが前記の範囲にあると、耐衝撃性を高めることができると共に、耐屈曲性が低下しにくく、硬化収縮によるカール発生の問題が発生し難い傾向がある。ハードコート層は、活性エネルギー線照射、或いは熱エネルギー付与により架橋構造を形成し得る反応性材料を含むハードコート組成物を硬化させて形成することができ、活性エネルギー線照射によるものが好ましい。活性エネルギー線は、活性種を発生する化合物を分解して活性種を発生させることができるエネルギー線と定義され、可視光、紫外線、赤外線、Ｘ線、α線、β線、γ線及び電子線などが挙げられ、好ましくは紫外線が挙げられる。前記ハードコート組成物は、ラジカル重合性化合物及びカチオン重合性化合物の少なくとも１種の重合物を含有する。 The thickness of the hard coat layer is not particularly limited, and may be, for example, 2 to 100 μm. When the thickness of the hard coat layer is within the above range, the impact resistance can be enhanced, the bending resistance is less likely to decrease, and the problem of curl generation due to curing shrinkage tends to be less likely to occur. The hard coat layer can be formed by curing a hard coat composition containing a reactive material capable of forming a crosslinked structure by irradiation with active energy rays or by applying thermal energy, and is preferably formed by irradiation with active energy rays. Active energy rays are defined as energy rays that can generate active species by decomposing compounds that generate active species, and are visible light, ultraviolet rays, infrared rays, X-rays, α rays, β rays, γ rays, and electron beams. And the like, preferably ultraviolet rays. The hard coat composition contains at least one polymer of a radically polymerizable compound and a cationically polymerizable compound.
　前記ラジカル重合性化合物は、ラジカル重合性基を有する化合物である。前記ラジカル重合性化合物が有するラジカル重合性基としては、ラジカル重合反応を生じ得る官能基であればよく、炭素‐炭素不飽和二重結合を含む基などが挙げられ、具体的には、ビニル基、（メタ）アクリロイル基などが挙げられる。なお、前記ラジカル重合性化合物が２個以上のラジカル重合性基を有する場合、これらのラジカル重合性基はそれぞれ同一であっても異なっていてもよい。前記ラジカル重合性化合物が１分子中に有するラジカル重合性基の数は、ハードコート層の硬度を向上する点から、好ましくは２以上である。前記ラジカル重合性化合物としては、反応性の高さの点から、好ましくは（メタ）アクリロイル基を有する化合物が挙げられ、具体的には１分子中に２～６個の（メタ）アクリロイル基を有する多官能アクリレートモノマーと称される化合物やエポキシ（メタ）アクリレート、ウレタン（メタ）アクリレート、ポリエステル（メタ）アクリレートと称される分子内に数個の（メタ）アクリロイル基を有する分子量が数百から数千のオリゴマーが挙げられ、好ましくはエポキシ（メタ）アクリレート、ウレタン（メタ）アクリレート及びポリエステル（メタ）アクリレートから選択された１種以上が挙げられる。 The radically polymerizable compound is a compound having a radically polymerizable group. The radically polymerizable group contained in the radically polymerizable compound may be a functional group capable of causing a radical polymerization reaction, and examples thereof include a group containing a carbon-carbon unsaturated double bond, and specifically, a vinyl group. , (Meta) acryloyl group and the like. When the radically polymerizable compound has two or more radically polymerizable groups, these radically polymerizable groups may be the same or different from each other. The number of radically polymerizable groups contained in one molecule of the radically polymerizable compound is preferably 2 or more from the viewpoint of improving the hardness of the hard coat layer. Examples of the radically polymerizable compound include compounds having a (meth) acryloyl group from the viewpoint of high reactivity, and specifically, 2 to 6 (meth) acryloyl groups in one molecule. Compounds called polyfunctional acrylate monomers and epoxy (meth) acrylates, urethane (meth) acrylates, and polyester (meth) acrylates have a molecular weight of several hundreds of (meth) acryloyl groups in the molecule. Thousands of oligomers are mentioned, preferably one or more selected from epoxy (meth) acrylates, urethane (meth) acrylates and polyester (meth) acrylates.
前記カチオン重合性化合物は、エポキシ基、オキセタニル基、ビニルエーテル基等のカチオン重合性基を有する化合物である。前記カチオン重合性化合物が１分子中に有するカチオン重合性基の数は、ハードコート層の硬度を向上する点から、好ましくは２以上であり、より好ましくは３以上である。
　また、前記カチオン重合性化合物としては、中でも、カチオン重合性基としてエポキシ基及びオキセタニル基の少なくとも１種を有する化合物が好ましい。エポキシ基、オキセタニル基等の環状エーテル基は、重合反応に伴う収縮が小さいという点から好ましい。また、環状エーテル基のうちエポキシ基を有する化合物は多様な構造の化合物が入手し易く、得られたハードコート層の耐久性に悪影響を与えず、ラジカル重合性化合物との相溶性もコントロールし易いという利点がある。また、環状エーテル基のうちオキセタニル基は、エポキシ基と比較して重合度が高くなりやすく、得られたハードコート層のカチオン重合性化合物から得られるネットワーク形成速度を早め、ラジカル重合性化合物と混在する領域でも未反応のモノマーを膜中に残さずに独立したネットワークを形成する等の利点がある。
　エポキシ基を有するカチオン重合性化合物としては、例えば、脂環族環を有する多価アルコールのポリグリシジルエーテル又は、シクロヘキセン環、シクロペンテン環含有化合物を、過酸化水素、過酸等の適当な酸化剤でエポキシ化する事によって得られる脂環族エポキシ樹脂；脂肪族多価アルコール、又はそのアルキレンオキサイド付加物のポリグリシジルエーテル、脂肪族長鎖多塩基酸のポリグリシジルエステル、グリシジル（メタ）アクリレートのホモポリマー、コポリマーなどの脂肪族エポキシ樹脂；ビスフェノールＡ、ビスフェノールＦや水添ビスフェノールＡ等のビスフェノール類、又はそれらのアルキレンオキサイド付加体、カプロラクトン付加体等の誘導体と、エピクロルヒドリンとの反応によって製造されるグリシジルエーテル、及びノボラックエポキシ樹脂等でありビスフェノール類から誘導されるグリシジルエーテル型エポキシ樹脂等が挙げられる。 The cationically polymerizable compound is a compound having a cationically polymerizable group such as an epoxy group, an oxetanyl group, and a vinyl ether group. The number of cationically polymerizable groups contained in one molecule of the cationically polymerizable compound is preferably 2 or more, and more preferably 3 or more, from the viewpoint of improving the hardness of the hard coat layer.
Further, as the cationically polymerizable compound, a compound having at least one epoxy group and an oxetanyl group as the cationically polymerizable group is preferable. A cyclic ether group such as an epoxy group or an oxetanyl group is preferable because the shrinkage associated with the polymerization reaction is small. Further, among the cyclic ether groups, compounds having an epoxy group are easily available, compounds having various structures are easily available, the durability of the obtained hard coat layer is not adversely affected, and compatibility with radically polymerizable compounds is easily controlled. There is an advantage. Further, among the cyclic ether groups, the oxetanyl group tends to have a higher degree of polymerization than the epoxy group, accelerates the network formation rate obtained from the cationically polymerizable compound of the obtained hard coat layer, and is mixed with the radically polymerizable compound. There are advantages such as forming an independent network without leaving unreacted monomers in the film even in the region where the polymer is formed.
Examples of the cationically polymerizable compound having an epoxy group include polyglycidyl ether of a polyhydric alcohol having an alicyclic ring, or a cyclohexene ring or cyclopentene ring-containing compound with an appropriate oxidizing agent such as hydrogen peroxide or peracid. Alicyclic epoxy resin obtained by epoxidation; polyglycidyl ether of aliphatic polyhydric alcohol or its alkylene oxide adduct, polyglycidyl ester of aliphatic long chain polybasic acid, homopolymer of glycidyl (meth) acrylate, An aliphatic epoxy resin such as a copolymer; a glycidyl ether produced by reacting bisphenols such as bisphenol A, bisphenol F and hydrogenated bisphenol A, or derivatives such as their alkylene oxide adducts and caprolactone adducts with epichlorohydrin. And glycidyl ether type epoxy resin which is a novolak epoxy resin and is derived from bisphenols and the like.
　前記ハードコート組成物は重合開始剤をさらに含むことができる。重合開始剤としては、ラジカル重合開始剤、カチオン重合開始剤、ラジカル及びカチオン重合開始剤等が挙げられ、適宜選択して用いられる。これらの重合開始剤は、活性エネルギー線照射及び加熱の少なくとも一種により分解されて、ラジカル又はカチオンを発生してラジカル重合とカチオン重合を進行させるものである。
　ラジカル重合開始剤は、活性エネルギー線照射及び加熱の少なくともいずれかによりラジカル重合を開始させる物質を放出することが可能であればよい。例えば、熱ラジカル重合開始剤としては、過酸化水素、過安息香酸等の有機過酸化物、アゾビスブチロニトリル等のアゾ化合物等があげられる。
　活性エネルギー線ラジカル重合開始剤としては、分子の分解でラジカルが生成されるＴｙｐｅ１型ラジカル重合開始剤と、３級アミンと共存して水素引き抜き型反応でラジカルを生成するＴｙｐｅ２型ラジカル重合開始剤があり、それらは単独で又は併用して使用される。
　カチオン重合開始剤は、活性エネルギー線照射及び加熱の少なくともいずれかによりカチオン重合を開始させる物質を放出することが可能であればよい。カチオン重合開始剤としては、芳香族ヨードニウム塩、芳香族スルホニウム塩、シクロペンタジエニル鉄（ＩＩ）錯体等が使用できる。これらは、構造の違いによって活性エネルギー線照射又は加熱のいずれかあるいはいずれでもカチオン重合を開始することができる。 The hard coat composition may further contain a polymerization initiator. Examples of the polymerization initiator include a radical polymerization initiator, a cationic polymerization initiator, a radical and a cationic polymerization initiator, and the like, which are appropriately selected and used. These polymerization initiators are decomposed by at least one of active energy ray irradiation and heating to generate radicals or cations to promote radical polymerization and cation polymerization.
The radical polymerization initiator may be any as long as it can release a substance that initiates radical polymerization by at least one of irradiation with active energy rays and heating. For example, examples of the thermal radical polymerization initiator include organic peroxides such as hydrogen peroxide and perbenzoic acid, and azo compounds such as azobisbutyronitrile.
Active energy ray radical polymerization initiators include Type 1 radical polymerization initiators, which generate radicals by decomposition of molecules, and Type 2 radical polymerization initiators, which coexist with tertiary amines and generate radicals by hydrogen abstraction type reactions. Yes, they are used alone or in combination.
The cationic polymerization initiator may be any one as long as it can release a substance that initiates cationic polymerization by at least one of activation energy ray irradiation and heating. As the cationic polymerization initiator, an aromatic iodonium salt, an aromatic sulfonium salt, a cyclopentadienyl iron (II) complex and the like can be used. These can initiate cationic polymerization by either irradiation with active energy rays or heating, depending on the difference in structure.
　前記重合開始剤は、前記ハードコート組成物全体１００質量％に対して好ましくは０．１～１０質量％を含むことができる。前記重合開始剤の含量が前記の範囲にあると、硬化を十分に進行させることができ、最終的に得られる塗膜の機械的物性や密着力を良好な範囲とすることができ、また、硬化収縮による接着力不良や割れ現象及びカール現象が発生し難くなる傾向がある。 The polymerization initiator can preferably contain 0.1 to 10% by mass with respect to 100% by mass of the entire hard coat composition. When the content of the polymerization initiator is in the above range, curing can proceed sufficiently, and the mechanical properties and adhesive strength of the finally obtained coating film can be in a good range. Poor adhesive strength due to curing shrinkage, cracking phenomenon, and curling phenomenon tend to be less likely to occur.
　前記ハードコート組成物は、溶剤及び添加剤からなる群から選択される一つ以上をさらに含むことができる。
　前記溶剤は、前記重合性化合物及び重合開始剤を溶解又は分散させることができるもので、本技術分野のハードコート組成物の溶剤として知られている溶剤であれば、本発明の効果を阻害しない範囲で、使用することができる。
　前記添加剤は、無機粒子、レベリング剤、安定剤、界面活性剤、帯電防止剤、潤滑剤、防汚剤などをさらに含むことができる。 The hard coat composition may further comprise one or more selected from the group consisting of solvents and additives.
The solvent can dissolve or disperse the polymerizable compound and the polymerization initiator, and any solvent known as a solvent for hard coat compositions in the present art does not impair the effects of the present invention. In the range, it can be used.
The additive may further contain inorganic particles, a leveling agent, a stabilizer, a surfactant, an antistatic agent, a lubricant, an antifouling agent and the like.
　紫外線吸収層は、紫外線吸収の機能を有する層であり、例えば、紫外線硬化型の透明樹脂、電子線硬化型の透明樹脂、及び熱硬化型の透明樹脂から選ばれる主材と、この主材に分散した紫外線吸収剤とから構成される。 The ultraviolet absorbing layer is a layer having an ultraviolet absorbing function. For example, a main material selected from an ultraviolet curable transparent resin, an electron beam curable transparent resin, and a thermosetting transparent resin, and the main material thereof. It is composed of a dispersed ultraviolet absorber.
　粘着層は、粘着性の機能を有する層であり、光学フィルムを他の部材に接着させる機能を有する。粘着層の形成材料としては、通常知られたものを用いることができる。例えば、熱硬化性樹脂組成物又は光硬化性樹脂組成物を用いることができる。この場合、事後的にエネルギーを供給することで熱硬化性樹脂組成物又は光硬化性樹脂組成物を高分子化し硬化させることができる。 The adhesive layer is a layer having an adhesive function, and has a function of adhering an optical film to another member. As a material for forming the adhesive layer, a commonly known material can be used. For example, a thermosetting resin composition or a photocurable resin composition can be used. In this case, the thermosetting resin composition or the photocurable resin composition can be polymerized and cured by supplying energy after the fact.
　粘着層は、感圧型接着剤（Ｐｒｅｓｓｕｒｅ　Ｓｅｎｓｉｔｉｖｅ　Ａｄｈｅｓｉｖｅ、ＰＳＡ）と呼ばれる、押圧により対象物に貼着される層であってもよい。感圧型接着剤は、「常温で粘着性を有し、軽い圧力で被着材に接着する物質」（ＪＩＳ　Ｋ　６８００）である粘着剤であってもよく、「特定成分を保護被膜（マイクロカプセル）に内容し、適当な手段（圧力、熱等）によって被膜を破壊するまでは安定性を保持できる接着剤」（ＪＩＳ　Ｋ　６８００）であるカプセル型接着剤であってもよい。 The adhesive layer may be a layer called a pressure-sensitive adhesive (Pressure Sensitive Adhesive, PSA), which is attached to an object by pressing. The pressure-sensitive adhesive may be an adhesive that is "a substance that has adhesiveness at room temperature and adheres to an adherend with a light pressure" (JIS K 6800), and "protects a specific component (microcapsules). ), And an adhesive that can maintain stability until the film is destroyed by an appropriate means (pressure, heat, etc.) ”(JIS K 6800).
　色相調整層は、色相調整の機能を有する層であり、光学フィルムを目的の色相に調整することができる層である。色相調整層は、例えば、樹脂及び着色剤を含有する層である。この着色剤としては、例えば、酸化チタン、酸化亜鉛、弁柄、チタニウムオキサイド系焼成顔料、群青、アルミン酸コバルト、及びカーボンブラック等の無機顔料；アゾ系化合物、キナクリドン系化合物、アンスラキノン系化合物、ペリレン系化合物、イソインドリノン系化合物、フタロシアニン系化合物、キノフタロン系化合物、スレン系化合物、及びジケトピロロピロール系化合物等の有機顔料；硫酸バリウム、及び炭酸カルシウム等の体質顔料；並びに塩基性染料、酸性染料、及び媒染染料等の染料を挙げることができる。 The hue adjustment layer is a layer having a hue adjustment function, and is a layer capable of adjusting the optical film to a desired hue. The hue adjusting layer is, for example, a layer containing a resin and a colorant. Examples of this colorant include inorganic pigments such as titanium oxide, zinc oxide, petals, titanium oxide-based calcined pigments, ultramarine, cobalt aluminate, and carbon black; azo compounds, quinacridone compounds, anthracinone compounds, and the like. Organic pigments such as perylene compounds, isoindolinone compounds, phthalocyanine compounds, quinophthalone compounds, slene compounds, and diketopyrrolopyrrole compounds; extender pigments such as barium sulfate and calcium carbonate; and basic dyes, Examples thereof include dyes such as acidic dyes and medium dyes.
　屈折率調整層は、屈折率調整の機能を有する層であり、例えば単層の光学フィルムとは異なる屈折率を有し、光学フィルムに所定の屈折率を付与することができる層である。屈折率調整層は、例えば、適宜選択された樹脂、及び場合によりさらに顔料を含有する樹脂層であってもよいし、金属の薄膜であってもよい。屈折率を調整する顔料としては、例えば、酸化珪素、酸化アルミニウム、酸化アンチモン、酸化錫、酸化チタン、酸化ジルコニウム及び酸化タンタルが挙げられる。該顔料の平均一次粒子径は、０．１μｍ以下であってもよい。顔料の平均一次粒子径を０．１μｍ以下とすることにより、屈折率調整層を透過する光の乱反射を防止し、透明度の低下を防止することができる。屈折率調整層に用いられる金属としては、例えば、酸化チタン、酸化タンタル、酸化ジルコニウム、酸化亜鉛、酸化錫、酸化ケイ素、酸化インジウム、酸窒化チタン、窒化チタン、酸窒化ケイ素、窒化ケイ素等の金属酸化物又は金属窒化物が挙げられる。 The refractive index adjusting layer is a layer having a function of adjusting the refractive index, for example, a layer having a refractive index different from that of a single-layer optical film and capable of imparting a predetermined refractive index to the optical film. The refractive index adjusting layer may be, for example, a resin layer appropriately selected and, in some cases, a resin layer further containing a pigment, or a thin film of metal. Examples of the pigment for adjusting the refractive index include silicon oxide, aluminum oxide, antimony oxide, tin oxide, titanium oxide, zirconium oxide and tantalum oxide. The average primary particle size of the pigment may be 0.1 μm or less. By setting the average primary particle size of the pigment to 0.1 μm or less, diffuse reflection of light transmitted through the refractive index adjusting layer can be prevented, and deterioration of transparency can be prevented. Examples of the metal used for the refractive index adjusting layer include metals such as titanium oxide, tantalum oxide, zirconium oxide, zinc oxide, tin oxide, silicon oxide, indium oxide, titanium oxynitride, titanium nitride, silicon oxynitride, and silicon nitride. Oxides or metal nitrides can be mentioned.
　本発明の一実施形態において、光学フィルムは、少なくとも一方の面（片面又は両面）に保護フィルムを有していてもよい。例えば光学フィルムの片面に機能層を有する場合には、保護フィルムは、光学フィルム側の表面又は機能層側の表面に積層されていてもよく、光学フィルム側と機能層側の両方に積層されていてもよい。光学フィルムの両面に機能層を有する場合には、保護フィルムは、片方の機能層側の表面に積層されていてもよく、両方の機能層側の表面に積層されていてもよい。保護フィルムは、光学フィルム又は機能層の表面を一時的に保護するためのフィルムであり、光学フィルム又は機能層の表面を保護できる剥離可能なフィルムである限り特に限定されない。保護フィルムとしては、例えば、ポリエチレンテレフタレート、ポリブチレンテレフタレート、ポリエチレンナフタレート等のポリエステル系樹脂フィルム；ポリエチレン、ポリプロピレンフィルムなどのポリオレフィン系樹脂フィルム、アクリル系樹脂フィルム等が挙げられ、ポリオレフィン系樹脂フィルム、ポリエチレンテレフタレート系樹脂フィルム及びアクリル系樹脂フィルムからなる群から選択されることが好ましい。光学フィルムが保護フィルムを２つ有する場合、各保護フィルムは同一であっても異なっていてもよい。 In one embodiment of the present invention, the optical film may have a protective film on at least one side (one side or both sides). For example, when the functional layer is provided on one side of the optical film, the protective film may be laminated on the surface on the optical film side or the surface on the functional layer side, and is laminated on both the optical film side and the functional layer side. You may. When the optical film has functional layers on both sides, the protective film may be laminated on the surface on one functional layer side or on the surfaces on both functional layer sides. The protective film is a film for temporarily protecting the surface of the optical film or the functional layer, and is not particularly limited as long as it is a peelable film capable of protecting the surface of the optical film or the functional layer. Examples of the protective film include polyester resin films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefin resin films such as polyethylene and polypropylene films, acrylic resin films, and the like, and polyolefin resin films and polyethylene. It is preferable to select from the group consisting of a terephthalate resin film and an acrylic resin film. When the optical film has two protective films, each protective film may be the same or different.
　保護フィルムの厚さは、特に限定されるものではないが、通常、１０～１２０μｍ、好ましくは１５～１１０μｍ、より好ましくは２０～１００μｍである。光学フィルムが保護フィルムを２つ有する場合、各保護フィルムの厚さは同一であっても異なっていてもよい。 The thickness of the protective film is not particularly limited, but is usually 10 to 120 μm, preferably 15 to 110 μm, and more preferably 20 to 100 μm. When the optical film has two protective films, the thickness of each protective film may be the same or different.
　〔光学フィルムの製造方法〕
　本発明の光学フィルムは、特に限定されないが、例えば以下の工程：
（ａ）前記ポリアミドイミド樹脂を含む液（樹脂ワニスと称する場合がある）を調製する工程（ワニス調製工程）、
（ｂ）樹脂ワニスを基材に塗布して塗膜を形成する工程（塗布工程）、及び
（ｃ）塗布された液（塗膜）を乾燥させて、光学フィルムを形成する工程（光学フィルム形成工程）
を含む方法によって製造することができる。 [Manufacturing method of optical film]
The optical film of the present invention is not particularly limited, but for example, the following steps:
(A) A step of preparing a liquid containing the polyamide-imide resin (sometimes referred to as a resin varnish) (varnish preparation step),
(B) A step of applying a resin varnish to a base material to form a coating film (coating step), and (c) a step of drying the applied liquid (coating film) to form an optical film (optical film formation). Process)
It can be manufactured by a method including.
　ワニス調製工程において、前記ポリアミドイミド樹脂を溶媒に溶解し、必要に応じて前記添加剤を添加して撹拌混合することにより樹脂ワニスを調製する。 In the varnish preparation step, the polyamide-imide resin is dissolved in a solvent, and if necessary, the additive is added and stirred and mixed to prepare a resin varnish.
　樹脂ワニスの調製に用いられる溶媒は、前記樹脂を溶解可能であれば特に限定されない。かかる溶媒としては、例えばＤＭＡｃ、ＤＭＦ等のアミド系溶媒；γ－ブチロラクトン、γ－バレロラクトン等のラクトン系溶媒；ジメチルスルホン、ジメチルスルホキシド、スルホラン等の含硫黄系溶媒；エチレンカーボネート、プロピレンカーボネート等のカーボネート系溶媒；及びそれらの組合せが挙げられる。これらの中でも、アミド系溶媒又はラクトン系溶媒が好ましい。これらの溶媒は単独又は二種以上組合せて使用できる。また、樹脂ワニスには水、アルコール系溶媒、ケトン系溶媒、非環状エステル系溶媒、エーテル系溶媒などが含まれてもよい。ワニスの固形分濃度は、好ましくは１～２５質量％、より好ましくは５～１５質量％である。なお、本明細書において、ワニスの固形分とは、ワニスから溶媒を除いた成分の合計量を示す。 The solvent used for preparing the resin varnish is not particularly limited as long as the resin can be dissolved. Examples of such a solvent include amide solvents such as DMAc and DMF; lactone solvents such as γ-butyrolactone and γ-valerolactone; sulfur-containing solvents such as dimethyl sulfoxide, dimethyl sulfoxide and sulfolane; ethylene carbonate, propylene carbonate and the like. Carbonated solvents; and combinations thereof. Among these, an amide solvent or a lactone solvent is preferable. These solvents can be used alone or in combination of two or more. Further, the resin varnish may contain water, an alcohol solvent, a ketone solvent, an acyclic ester solvent, an ether solvent and the like. The solid content concentration of the varnish is preferably 1 to 25% by mass, more preferably 5 to 15% by mass. In the present specification, the solid content of the varnish indicates the total amount of the components of the varnish excluding the solvent.
　塗布工程において、公知の塗布方法により、基材上にワニスを塗布して塗膜を形成する。公知の塗布方法としては、例えばワイヤーバーコーティング法、リバースコーティング、グラビアコーティング等のロールコーティング法、ダイコート法、カンマコート法、リップコート法、スピンコーティング法、スクリーンコーティング法、ファウンテンコーティング法、ディッピング法、スプレー法、流涎成形法等が挙げられる。 In the coating process, a varnish is applied onto the substrate by a known coating method to form a coating film. Known coating methods include, for example, wire bar coating method, reverse coating, roll coating method such as gravure coating, die coating method, comma coating method, lip coating method, spin coating method, screen coating method, fountain coating method, dipping method, and the like. Examples include a spray method and a salivation molding method.
　光学フィルム形成工程において、塗膜を乾燥し、基材から剥離することによって、光学フィルムを形成することができる。剥離後にさらに光学フィルムを乾燥する乾燥工程を行ってもよい。塗膜の乾燥は、通常５０～３５０℃、好ましくは５０～２３０℃の温度にて行うことができる。本発明の好適な実施形態において、段階的に乾燥を行うことが好ましい。高分子量樹脂を含むワニスは高粘度になりやすく、一般的に均一なフィルムを得ることが困難となり、透明性に優れるフィルムを得にくくなる。そこで、段階的に乾燥を行うことにより、高分子量樹脂を含むワニスを均一に乾燥することができる。必要に応じて、不活性雰囲気又は減圧の条件下において塗膜の乾燥を行ってよい。また、光学フィルムの乾燥を真空条件下で行うと、フィルム中に微小な気泡が発生、残存することがあり、光学特性が低下する要因となるため大気圧下で行うことが好ましい。 In the optical film forming step, the optical film can be formed by drying the coating film and peeling it from the substrate. After the peeling, a drying step of further drying the optical film may be performed. Drying of the coating film is usually 50 ~ 350 ° C., the good Mashiku can be carried out at a temperature of 50 ~ 230 ° C.. In a preferred embodiment of the present invention, it is preferable to carry out drying step by step. A varnish containing a high molecular weight resin tends to have a high viscosity, and it is generally difficult to obtain a uniform film, and it is difficult to obtain a film having excellent transparency. Therefore, the varnish containing the high molecular weight resin can be uniformly dried by performing the drying step by step. If necessary, the coating film may be dried under an inert atmosphere or under reduced pressure conditions. Further, when the optical film is dried under vacuum conditions, minute bubbles may be generated and remain in the film, which causes deterioration of optical characteristics. Therefore, it is preferable to perform the drying under atmospheric pressure.
　基材の例としては、ＰＥＴフィルム、ＰＥＮフィルム、他のポリイミド系樹脂又はポリアミド系樹脂フィルム等が挙げられる。中でも、耐熱性に優れる観点から、ＰＥＴフィルム、ＰＥＮフィルム等が好ましく、さらに光学フィルムとの密着性及びコストの観点から、ＰＥＴフィルムがより好ましい。 Examples of the base material include PET film, PEN film, other polyimide-based resin, polyamide-based resin film, and the like. Among them, PET film, PEN film and the like are preferable from the viewpoint of excellent heat resistance, and PET film is more preferable from the viewpoint of adhesion to the optical film and cost.
　本発明の光学フィルムは、表示装置、中でもフレキシブル表示装置の前面板（ウインドウフィルムということがある）、特にローラブルディスプレイやフォルダブルディスプレイの前面板として好適に使用できる。すなわち、本発明の光学フィルムは、フレキシブル表示装置の前面板用フィルムであることが好ましい。該前面板は、フレキシブル表示装置の表示素子を保護する機能を有する。なお、フレキシブル表示装置とは、画像表示装置を繰り返し折り曲げる、繰り返し巻く等の操作を伴い使用される表示装置である。このような繰り返しの折り曲げ操作等を伴い使用されるフレキシブル表示装置の前面板には高い耐屈曲性、特に耐折性が求められる。また、前面板には、高い視認性も求められる。画像表示装置の内部で使用される画像表示装置の基板用のフィルムと比較して、画像表示装置の前面板、特にフレキシブル表示装置の前面板用のフィルムには、高い視認性が求められると共に、高い耐屈曲性が求められる。例えば、本発明のフィルムは、フレキシブル表示装置の前面板用に用いる場合の視認性を高めやすい観点から、上記に記載したような全光線透過率、ヘーズ及び／又はＹＩ値を有することが好ましく、また、フレキシブル表示装置の前面板として用いる場合の耐屈曲性、特に耐折性を高めやすい観点から、上記に記載したようなＭＩＴ耐折疲労試験における耐折回数を満たすことが好ましい。表示装置としては、テレビ、スマートフォン、携帯電話、カーナビゲーション、タブレットＰＣ、携帯ゲーム機、電子ペーパー、インジケーター、掲示板、時計、及びスマートウォッチ等のウェアラブルデバイス等が挙げられる。フレキシブルディスプレイとしては、フレキシブル特性を有する表示装置、例えばテレビ、スマートフォン、携帯電話、スマートウォッチ等が挙げられる。フレキシブル表示装置としては、フレキシブル特性を有する全ての画像表示装置が挙げられ、例えば上記のようなローラブルディスプレイやフォルダブルディスプレイが挙げられる。ローラブルディスプレイとは、前面板を含む画像表示部分がロール状に巻き取られており、該画像表示部分を引き出して平面又は曲面にした状態で使用される画像表示装置であり、ロール状に巻き取る等の操作が使用の度に行われるような画像表示装置である。また、フォルダブルディスプレイとは、前面板を含む画像表示部分が折り曲げられており、該画像表示部分を開いて平面又は曲面にした状態で使用される画像表示装置であり、折り曲げる等の操作が使用の度に行われるような画像表示装置である。このような巻取り、折り曲げ等の操作が繰り返し行われる画像表示装置をフレキシブル表示装置と称する。 The optical film of the present invention can be suitably used as a front plate of a display device, particularly a flexible display device (sometimes referred to as a window film), particularly a front plate of a rollable display or a foldable display. That is, the optical film of the present invention is preferably a film for the front plate of a flexible display device. The front plate has a function of protecting the display element of the flexible display device. The flexible display device is a display device that is used with operations such as repeatedly bending and repeatedly winding the image display device. The front plate of a flexible display device used with such repeated bending operations is required to have high bending resistance, particularly folding resistance. The front plate is also required to have high visibility. Compared with the film for the substrate of the image display device used inside the image display device, the front plate of the image display device, particularly the film for the front plate of the flexible display device, is required to have high visibility and high visibility. High bending resistance is required. For example, the film of the present invention preferably has the total light transmittance, haze and / or YI value as described above from the viewpoint of easily enhancing visibility when used for the front plate of a flexible display device. Further, from the viewpoint of easily improving the bending resistance, particularly the folding resistance when used as the front plate of the flexible display device, it is preferable to satisfy the number of folding resistances in the MIT folding resistance test as described above. Examples of display devices include wearable devices such as televisions, smartphones, mobile phones, car navigation systems, tablet PCs, portable game machines, electronic papers, indicators, bulletin boards, watches, and smart watches. Examples of the flexible display include display devices having flexible characteristics, such as televisions, smartphones, mobile phones, and smart watches. Examples of the flexible display device include all image display devices having flexible characteristics, and examples thereof include the rollable display and the foldable display as described above. The rollable display is an image display device in which an image display portion including a front plate is wound in a roll shape, and the image display portion is pulled out to form a flat surface or a curved surface, and is wound in a roll shape. It is an image display device in which operations such as taking are performed each time it is used. A foldable display is an image display device in which an image display portion including a front plate is bent and is used in a state where the image display portion is opened and made into a flat surface or a curved surface, and an operation such as folding is used. It is an image display device that is performed every time. An image display device in which such operations such as winding and bending are repeatedly performed is referred to as a flexible display device.
　〔フレキシブル表示装置〕
　本発明は、本発明の光学フィルムを備える、フレキシブル表示装置を包含する。本発明の光学フィルムは、好ましくはフレキシブル表示装置において前面板として用いられ、該前面板はウインドウフィルムと称されることがある。該フレキシブル表示装置は、フレキシブル表示装置用積層体と、有機ＥＬ表示パネルとからなり、有機ＥＬ表示パネルに対して視認側にフレキシブル表示装置用積層体が配置され、折り曲げ可能に構成されている。フレキシブル表示装置用積層体としては、さらに偏光板、タッチセンサを含有していてもよく、それらの積層順は任意であるが、視認側からウインドウフィルム、偏光板、タッチセンサ又はウインドウフィルム、タッチセンサ、偏光板の順に積層されていることが好ましい。タッチセンサよりも視認側に偏光板が存在すると、タッチセンサのパターンが視認されにくくなり表示画像の視認性が良くなるので好ましい。それぞれの部材は接着剤、粘着剤等を用いて積層することができる。また、前記ウインドウフィルム、偏光板、タッチセンサのいずれかの層の少なくとも一面に形成された遮光パターンを具備することができる。 [Flexible display device]
The present invention includes a flexible display device comprising the optical film of the present invention. The optical film of the present invention is preferably used as a front plate in a flexible display device, and the front plate may be referred to as a window film. The flexible display device includes a laminate for a flexible display device and an organic EL display panel, and the laminate for the flexible display device is arranged on the visual side with respect to the organic EL display panel and is configured to be bendable. The laminated body for the flexible display device may further contain a polarizing plate and a touch sensor, and the stacking order thereof is arbitrary, but from the visual side, a window film, a polarizing plate, a touch sensor or a window film, and a touch sensor. , It is preferable that the polarizing plates are laminated in this order. If a polarizing plate is present on the visual side of the touch sensor, the pattern of the touch sensor is less likely to be visually recognized and the visibility of the displayed image is improved, which is preferable. Each member can be laminated using an adhesive, an adhesive, or the like. Further, a light-shielding pattern formed on at least one surface of any layer of the window film, the polarizing plate, and the touch sensor can be provided.
　＜偏光板＞
　本発明のフレキシブル表示装置は、上記の通り、偏光板、中でも円偏光板をさらに備えることが好ましい。円偏光板は、直線偏光板にλ／４位相差板を積層することにより右円偏光成分又は左円偏光成分のみを透過させる機能を有する機能層である。例えば外光を右円偏光に変換して有機ＥＬパネルで反射されて左円偏光となった外光を遮断し、有機ＥＬの発光成分のみを透過させることで反射光の影響を抑制して画像を見やすくするために用いられる。円偏光機能を達成するためには、直線偏光板の吸収軸とλ／４位相差板の遅相軸は理論上４５°である必要があるが、実用的には４５±１０°である。直線偏光板とλ／４位相差板は必ずしも隣接して積層される必要はなく、吸収軸と遅相軸の関係が前述の範囲を満足していればよい。全波長において完全な円偏光を達成することが好ましいが実用上は必ずしもその必要はないので本発明における円偏光板は楕円偏光板をも包含する。直線偏光板の視認側にさらにλ／４位相差フィルムを積層して、出射光を円偏光とすることで偏光サングラスをかけた状態での視認性を向上させることも好ましい。 <Polarizer>
As described above, the flexible display device of the present invention preferably further includes a polarizing plate, particularly a circular polarizing plate. The circular polarizing plate is a functional layer having a function of transmitting only a right circularly polarized light component or a left circularly polarized light component by laminating a λ / 4 retardation plate on a linear polarizing plate. For example, the external light is converted to right-handed circularly polarized light, reflected by the organic EL panel to block the left-handed circularly polarized light, and only the light emitting component of the organic EL is transmitted to suppress the influence of the reflected light. It is used to make it easier to see. In order to achieve the circularly polarized light function, the absorption axis of the linear polarizing plate and the slow axis of the λ / 4 retardation plate must theoretically be 45 °, but practically, they are 45 ± 10 °. The linear polarizing plate and the λ / 4 retardation plate do not necessarily have to be laminated adjacent to each other, and the relationship between the absorption axis and the slow phase axis may satisfy the above range. It is preferable to achieve perfect circularly polarized light at all wavelengths, but it is not always necessary in practical use. Therefore, the circularly polarizing plate in the present invention also includes an elliptical polarizing plate. It is also preferable to further laminate a λ / 4 retardation film on the visible side of the linear polarizing plate to convert the emitted light into circularly polarized light to improve the visibility when wearing polarized sunglasses.
　直線偏光板は、透過軸方向に振動している光は通すが、それとは垂直な振動成分の偏光を遮断する機能を有する機能層である。前記直線偏光板は、直線偏光子単独又は直線偏光子及びその少なくとも一面に貼り付けられた保護フィルムを備えた構成であってもよい。前記直線偏光板の厚さは、２００μｍ以下であってもよく、好ましくは、０．５～１００μｍである。直線偏光板の厚さが前記の範囲にあると直線偏光板の柔軟性が低下し難い傾向にある。 The linear polarizing plate is a functional layer that allows light vibrating in the transmission axis direction to pass through, but has the function of blocking the polarization of vibration components perpendicular to it. The linear polarizing plate may be configured to include a linear polarizing element alone or a linear polarizing element and a protective film attached to at least one surface thereof. The thickness of the linear polarizing plate may be 200 μm or less, preferably 0.5 to 100 μm. When the thickness of the linear polarizing plate is within the above range, the flexibility of the linear polarizing plate tends to be difficult to decrease.
　前記直線偏光子は、ポリビニルアルコール（以下、ＰＶＡと略すことがある）系フィルムを染色、延伸することで製造されるフィルム型偏光子であってもよい。延伸によって配向したＰＶＡ系フィルムに、ヨウ素等の二色性色素が吸着、又はＰＶＡに吸着した状態で延伸されることで二色性色素が配向し、偏光性能を発揮する。前記フィルム型偏光子の製造においては、他に膨潤、ホウ酸による架橋、水溶液による洗浄、乾燥等の工程を有していてもよい。延伸や染色工程はＰＶＡ系フィルム単独で行ってもよいし、ポリエチレンテレフタレートのような他のフィルムと積層された状態で行うこともできる。用いられるＰＶＡ系フィルムの厚さは好ましくは１０～１００μｍであり、前記延伸倍率は好ましくは２～１０倍である。
　さらに前記偏光子の他の一例としては、液晶偏光組成物を塗布して形成する液晶塗布型偏光子が挙げられる。前記液晶偏光組成物は、液晶性化合物及び二色性色素化合物を含むことができる。前記液晶性化合物は、液晶状態を示す性質を有していればよく、特にスメクチック相等の高次の配向状態を有していると高い偏光性能を発揮することができるため好ましい。また、液晶性化合物は、重合性官能基を有することが好ましい。
　前記二色性色素化合物は、前記液晶化合物とともに配向して二色性を示す色素であって、重合性官能基を有していてもよく、また、二色性色素自身が液晶性を有していてもよい。
　液晶偏光組成物に含まれる化合物のいずれかは重合性官能基を有する。前記液晶偏光組成物はさらに開始剤、溶剤、分散剤、レベリング剤、安定剤、界面活性剤、架橋剤、シランカップリング剤などを含むことができる。
　前記液晶偏光層は、配向膜上に液晶偏光組成物を塗布して液晶偏光層を形成することにより製造される。液晶偏光層は、フィルム型偏光子に比べて厚さを薄く形成することができ、その厚さは好ましくは０．５～１０μｍ、より好ましくは１～５μｍである。 The linear polarizer may be a film-type polarizer produced by dyeing and stretching a polyvinyl alcohol (hereinafter, may be abbreviated as PVA) -based film. A dichroic dye such as iodine is adsorbed on the PVA-based film oriented by stretching, or the dichroic dye is oriented in a state of being adsorbed on the PVA to exhibit polarization performance. In the production of the film-type polarizer, other steps such as swelling, cross-linking with boric acid, washing with an aqueous solution, and drying may be included. The stretching and dyeing steps may be performed on the PVA-based film alone, or may be performed in a state of being laminated with another film such as polyethylene terephthalate. The thickness of the PVA-based film used is preferably 10 to 100 μm, and the draw ratio is preferably 2 to 10 times.
Further, as another example of the polarizer, there is a liquid crystal coating type polarizer formed by coating a liquid crystal polarizing composition. The liquid crystal polarizing composition may contain a liquid crystal compound and a dichroic dye compound. The liquid crystal compound may have a property of exhibiting a liquid crystal state, and is particularly preferable when it has a higher-order orientation state such as a smectic phase because it can exhibit high polarization performance. Further, the liquid crystal compound preferably has a polymerizable functional group.
The dichroic dye compound is a dye that is oriented together with the liquid crystal compound to exhibit dichroism, and may have a polymerizable functional group, and the dichroic dye itself has a liquid crystal property. May be.
Any of the compounds contained in the liquid crystal polarizing composition has a polymerizable functional group. The liquid crystal polarizing composition can further contain an initiator, a solvent, a dispersant, a leveling agent, a stabilizer, a surfactant, a cross-linking agent, a silane coupling agent and the like.
The liquid crystal polarizing layer is manufactured by applying a liquid crystal polarizing composition on an alignment film to form a liquid crystal polarizing layer. The liquid crystal polarizing layer can be formed to be thinner than the film-type polarizing element, and the thickness is preferably 0.5 to 10 μm, more preferably 1 to 5 μm.
　前記配向膜は、例えば基材上に配向膜形成組成物を塗布し、ラビング、偏光照射等により配向性を付与することにより製造される。前記配向膜形成組成物は、配向剤を含み、さらに溶剤、架橋剤、開始剤、分散剤、レベリング剤、シランカップリング剤等を含んでいてもよい。前記配向剤としては、例えば、ポリビニルアルコール類、ポリアクリレート類、ポリアミック酸類、ポリイミド類が挙げられる。偏光照射により配向性を付与する配向剤を用いる場合、シンナメート基を含む配向剤を使用することが好ましい。前記配向剤として使用される高分子のＭｗは、例えば、１０，０００～１，０００，０００程度である。前記配向膜の厚さは、好ましくは５～１０，０００ｎｍであり、配向規制力が十分に発現される点で、より好ましくは１０～５００ｎｍである。
　前記液晶偏光層は基材から剥離して転写して積層することもできるし、前記基材をそのまま積層することもできる。前記基材が、保護フィルムや位相差板、ウインドウフィルムの透明基材としての役割を担うことも好ましい。 The alignment film is produced, for example, by applying an alignment film forming composition on a base material and imparting orientation by rubbing, polarized light irradiation, or the like. The alignment film forming composition contains an alignment agent, and may further contain a solvent, a cross-linking agent, an initiator, a dispersant, a leveling agent, a silane coupling agent, and the like. Examples of the alignment agent include polyvinyl alcohols, polyacrylates, polyamic acids, and polyimides. When an orientation agent that imparts orientation by polarization irradiation is used, it is preferable to use an orientation agent containing a synnamate group. The Mw of the polymer used as the alignment agent is, for example, about 10,000 to 1,000,000. The thickness of the alignment film is preferably 5 to 10,000 nm, and more preferably 10 to 500 nm in that the alignment regulating force is sufficiently exhibited.
The liquid crystal polarizing layer can be peeled off from the base material, transferred and laminated, or the base material can be laminated as it is. It is also preferable that the base material serves as a transparent base material for a protective film, a retardation plate, and a window film.
　前記保護フィルムとしては、透明な高分子フィルムであればよく前記ウインドウフィルムの透明基材に使用される材料や添加剤と同じものが使用できる。また、エポキシ樹脂等のカチオン硬化組成物やアクリレート等のラジカル硬化組成物を塗布して硬化して得られるコーティング型の保護フィルムであってもよい。該保護フィルムは、必要により可塑剤、紫外線吸収剤、赤外線吸収剤、顔料や染料のような着色剤、蛍光増白剤、分散剤、熱安定剤、光安定剤、帯電防止剤、酸化防止剤、滑剤、溶剤等を含んでいてもよい。該保護フィルムの厚さは、好ましくは２００μｍ以下、より好ましくは１～１００μｍである。保護フィルムの厚さが前記の範囲にあると、該フィルムの柔軟性が低下し難い傾向にある。 As the protective film, any transparent polymer film may be used, and the same materials and additives used for the transparent base material of the window film can be used. Further, it may be a coating type protective film obtained by applying a cationic curing composition such as an epoxy resin or a radical curing composition such as acrylate and curing the film. The protective film may be a plasticizer, an ultraviolet absorber, an infrared absorber, a colorant such as a pigment or a dye, a fluorescent whitening agent, a dispersant, a heat stabilizer, a light stabilizer, an antioxidant, an antioxidant, if necessary. , Lubricants, solvents and the like may be contained. The thickness of the protective film is preferably 200 μm or less, more preferably 1 to 100 μm. When the thickness of the protective film is in the above range, the flexibility of the film tends to be difficult to decrease.
　前記λ／４位相差板は、入射光の進行方向に直行する方向（フィルムの面内方向）にλ／４の位相差を与えるフィルムである。前記λ／４位相差板は、セルロース系フィルム、オレフィン系フィルム、ポリカーボネート系フィルム等の高分子フィルムを延伸することで製造される延伸型位相差板であってもよい。前記λ／４位相差板は、必要により位相差調整剤、可塑剤、紫外線吸収剤、赤外線吸収剤、顔料や染料のような着色剤、蛍光増白剤、分散剤、熱安定剤、光安定剤、帯電防止剤、酸化防止剤、滑剤、溶剤等を含んでいてもよい。
　前記延伸型位相差板の厚さは、好ましくは２００μｍ以下、より好ましくは１～１００μｍである。延伸型位相差板の厚さが前記の範囲にあると、該延伸型位相差板の柔軟性が低下し難い傾向にある。
　さらに前記λ／４位相差板の他の一例としては、液晶組成物を塗布して形成する液晶塗布型位相差板が挙げられる。
　前記液晶組成物は、ネマチック、コレステリック、スメクチック等の液晶状態を示す液晶性化合物を含む。前記液晶性化合物は、重合性官能基を有する。
　前記液晶組成物は、さらに開始剤、溶剤、分散剤、レベリング剤、安定剤、界面活性剤、架橋剤、シランカップリング剤などを含むことができる。
　前記液晶塗布型位相差板は、前記液晶偏光層と同様に、液晶組成物を下地上に塗布、硬化して液晶位相差層を形成することで製造することができる。液晶塗布型位相差板は、延伸型位相差板に比べて厚さを薄く形成することができる。前記液晶偏光層の厚さは、好ましくは０．５～１０μｍ、より好ましくは１～５μｍである。
　前記液晶塗布型位相差板は基材から剥離して転写して積層することもできるし、前記基材をそのまま積層することもできる。前記基材が、保護フィルムや位相差板、ウインドウフィルムの透明基材としての役割を担うことも好ましい。 The λ / 4 retardation plate is a film that gives a retardation of λ / 4 in a direction orthogonal to the traveling direction of incident light (in-plane direction of the film). The λ / 4 retardation plate may be a stretch-type retardation plate manufactured by stretching a polymer film such as a cellulose-based film, an olefin-based film, or a polycarbonate-based film. The λ / 4 retardation plate may be used as a retardation adjuster, a plastic agent, an ultraviolet absorber, an infrared absorber, a colorant such as a pigment or a dye, a fluorescent whitening agent, a dispersant, a heat stabilizer, and a light stabilizer. It may contain an agent, an antioxidant, an antioxidant, a lubricant, a solvent and the like.
The thickness of the stretched retardation plate is preferably 200 μm or less, more preferably 1 to 100 μm. When the thickness of the stretchable retardation plate is within the above range, the flexibility of the stretchable retardation plate tends to be difficult to decrease.
Further, as another example of the λ / 4 retardation plate, there is a liquid crystal coating type retardation plate formed by coating a liquid crystal composition.
The liquid crystal composition contains a liquid crystal compound exhibiting a liquid crystal state such as nematic, cholesteric, and smectic. The liquid crystal compound has a polymerizable functional group.
The liquid crystal composition can further contain an initiator, a solvent, a dispersant, a leveling agent, a stabilizer, a surfactant, a cross-linking agent, a silane coupling agent, and the like.
The liquid crystal coating type retardation plate can be manufactured by applying a liquid crystal composition on a substrate and curing the liquid crystal composition to form a liquid crystal retardation layer, similarly to the liquid crystal polarizing layer. The liquid crystal coating type retardation plate can be formed to be thinner than the stretch type retardation plate. The thickness of the liquid crystal polarizing layer is preferably 0.5 to 10 μm, more preferably 1 to 5 μm.
The liquid crystal coating type retardation plate can be peeled off from the base material, transferred and laminated, or the base material can be laminated as it is. It is also preferable that the base material serves as a transparent base material for a protective film, a retardation plate, and a window film.
　一般的には、短波長ほど複屈折が大きく長波長になるほど小さな複屈折を示す材料が多い。この場合には全可視光領域でλ／４の位相差を達成することはできないので、視感度の高い５６０ｎｍ付近に対してλ／４となるように、面内位相差は、好ましくは１００～１８０ｎｍ、より好ましくは１３０～１５０ｎｍとなるように設計される。通常とは逆の複屈折率波長分散特性を有する材料を用いた逆分散λ／４位相差板は、視認性が良好となる点で好ましい。このような材料としては、例えば延伸型位相差板は特開２００７－２３２８７３号公報等に、液晶塗布型位相差板は特開２０１０－３０９７９号公報等に記載されているものを用いることができる。
　また、他の方法としてはλ／２位相差板と組合せることで広帯域λ／４位相差板を得る技術も知られている（例えば、特開平１０－９０５２１号公報など）。λ／２位相差板もλ／４位相差板と同様の材料方法で製造される。延伸型位相差板と液晶塗布型位相差板の組合せは任意であるが、どちらも液晶塗布型位相差板を用いることにより厚さを薄くすることができる。
　前記円偏光板には斜め方向の視認性を高めるために、正のＣプレートを積層する方法が知られている（例えば、特開２０１４－２２４８３７号公報など）。正のＣプレートは、液晶塗布型位相差板であっても延伸型位相差板であってもよい。該位相差板の厚さ方向の位相差は、好ましくは－２００～－２０ｎｍ、より好ましくは－１４０～－４０ｎｍである。 In general, there are many materials that exhibit larger birefringence at shorter wavelengths and smaller birefringence at longer wavelengths. In this case, since it is not possible to achieve a phase difference of λ / 4 in the entire visible light region, the in-plane phase difference is preferably 100 to 4 so that it becomes λ / 4 with respect to the vicinity of 560 nm, which has high visual sensitivity. It is designed to be 180 nm, more preferably 130-150 nm. A reverse dispersion λ / 4 retardation plate using a material having a birefringence wavelength dispersion characteristic opposite to the usual one is preferable in that visibility is improved. As such a material, for example, a stretchable retardation plate can be used as described in JP-A-2007-232873, and a liquid crystal-coated retardation plate can be used as described in JP-A-2010-30979. ..
Further, as another method, a technique for obtaining a wideband λ / 4 retardation plate by combining with a λ / 2 retardation plate is also known (for example, Japanese Patent Application Laid-Open No. 10-90521). The λ / 2 retardation plate is also manufactured by the same material method as the λ / 4 retardation plate. The combination of the stretchable retardation plate and the liquid crystal coating type retardation plate is arbitrary, but the thickness can be reduced by using the liquid crystal coating type retardation plate in both cases.
A method of laminating a positive C plate on the circularly polarizing plate in order to improve visibility in an oblique direction is known (for example, Japanese Patent Application Laid-Open No. 2014-224738). The positive C plate may be a liquid crystal coating type retardation plate or a stretched retardation plate. The phase difference in the thickness direction of the retardation plate is preferably −200 to −20 nm, more preferably −140 to −40 nm.
　〔タッチセンサ〕
　本発明のフレキシブル表示装置は、上記の通り、タッチセンサをさらに備えることが好ましい。タッチセンサは入力手段として用いられる。タッチセンサとしては、抵抗膜方式、表面弾性波方式、赤外線方式、電磁誘導方式、静電容量方式等様々な様式が挙げられ、好ましくは静電容量方式が挙げられる。
　静電容量方式タッチセンサは活性領域及び前記活性領域の外郭部に位置する非活性領域に区分される。活性領域は表示パネルで画面が表示される領域（表示部）に対応する領域であって、使用者のタッチが感知される領域であり、非活性領域は表示装置で画面が表示されない領域（非表示部）に対応する領域である。タッチセンサはフレキシブルな特性を有する基板と、前記基板の活性領域に形成された感知パターンと、前記基板の非活性領域に形成され、前記感知パターンとパッド部を介して外部の駆動回路と接続するための各センシングラインを含むことができる。フレキシブルな特性を有する基板としては、前記ウインドウフィルムの透明基板と同様の材料が使用できる。 [Touch sensor]
As described above, the flexible display device of the present invention preferably further includes a touch sensor. The touch sensor is used as an input means. Examples of the touch sensor include various types such as a resistive film method, a surface acoustic wave method, an infrared method, an electromagnetic induction method, and a capacitance method, and a capacitance method is preferable.
The capacitive touch sensor is divided into an active region and an inactive region located outside the active region. The active area is an area corresponding to the area where the screen is displayed on the display panel (display unit), the area where the user's touch is detected, and the inactive area is the area where the screen is not displayed on the display device (non-active area). This is the area corresponding to the display unit). The touch sensor is formed in a substrate having flexible characteristics, a sensing pattern formed in an active region of the substrate, and an inactive region of the substrate, and is connected to an external drive circuit via the sensing pattern and a pad portion. Each sensing line for can be included. As the substrate having flexible characteristics, the same material as the transparent substrate of the window film can be used.
　前記感知パターンは、第１方向に形成された第１パターン及び第２方向に形成された第２パターンを備えることができる。第１パターンと第２パターンとは互いに異なる方向に配置される。第１パターン及び第２パターンは、同一層に形成され、タッチされる地点を感知するためには、それぞれのパターンが電気的に接続されなければならない。第１パターンは複数の単位パターンが継ぎ手を介して互いに接続された形態であるが、第２パターンは複数の単位パターンがアイランド形態に互いに分離された構造になっているので、第２パターンを電気的に接続するためには別途のブリッジ電極が必要である。第２パターンの接続のための電極には、周知の透明電極を適用することができる。該透明電極の素材としては、例えば、インジウムスズ酸化物（ＩＴＯ）、インジウム亜鉛酸化物（ＩＺＯ）、亜鉛酸化物（ＺｎＯ）、インジウム亜鉛スズ酸化物（ＩＺＴＯ）、インジウムガリウム亜鉛酸化物（ＩＧＺＯ）、カドミウムスズ酸化物（ＣＴＯ）、ＰＥＤＯＴ（ｐｏｌｙ（３，４－ｅｔｈｙｌｅｎｅｄｉｏｘｙｔｈｉｏｐｈｅｎｅ））、炭素ナノチューブ（ＣＮＴ）、グラフェン及び金属ワイヤなどが挙げられ、好ましくはＩＴＯが挙げられる。これらは単独又は２種以上混合して使用できる。金属ワイヤに使用される金属は特に限定されず、例えば、銀、金、アルミニウム、銅、鉄、ニッケル、チタン、セレニウム及びクロムなどが挙げられ、これらは単独又は２種以上混合して使用することができる。
　ブリッジ電極は感知パターン上部に絶縁層を介して前記絶縁層上部に形成されることができ、基板上にブリッジ電極が形成されており、その上に絶縁層及び感知パターンを形成することができる。前記ブリッジ電極は感知パターンと同じ素材で形成することもでき、モリブデン、銀、アルミニウム、銅、パラジウム、金、白金、亜鉛、スズ、チタン又はこれらのうちの２種以上の合金で形成することもできる。
　第１パターンと第２パターンは電気的に絶縁されなければならないので、感知パターンとブリッジ電極の間には絶縁層が形成される。該絶縁層は、第１パターンの継ぎ手とブリッジ電極との間にのみ形成することや、感知パターン全体を覆う層として形成することもできる。感知パターン全体を覆う層の場合、ブリッジ電極は絶縁層に形成されたコンタクトホールを介して第２パターンを接続することができる。 The sensing pattern can include a first pattern formed in the first direction and a second pattern formed in the second direction. The first pattern and the second pattern are arranged in different directions from each other. The first pattern and the second pattern are formed in the same layer, and the respective patterns must be electrically connected in order to sense the touched point. The first pattern is a form in which a plurality of unit patterns are connected to each other via a joint, but the second pattern has a structure in which a plurality of unit patterns are separated from each other in an island form, so that the second pattern is electrically operated. A separate bridge electrode is required for the connection. A well-known transparent electrode can be applied to the electrode for connecting the second pattern. Examples of the material of the transparent electrode include indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc oxide (IZTO), and indium gallium zinc oxide (IGZO). , Cadmium tin oxide (CTO), PEDOT (poly (3,4-ethylenedioxythiophene)), carbon nanotubes (CNT), graphene, metal wire and the like, preferably ITO. These can be used alone or in combination of two or more. The metal used for the metal wire is not particularly limited, and examples thereof include silver, gold, aluminum, copper, iron, nickel, titanium, selenium, and chromium, and these may be used alone or in combination of two or more. Can be done.
The bridge electrode can be formed on the upper part of the insulating layer via the insulating layer on the upper part of the sensing pattern, the bridge electrode is formed on the substrate, and the insulating layer and the sensing pattern can be formed on the bridge electrode. The bridge electrode may be formed of the same material as the sensing pattern, or may be formed of molybdenum, silver, aluminum, copper, palladium, gold, platinum, zinc, tin, titanium or two or more alloys thereof. it can.
Since the first pattern and the second pattern must be electrically insulated, an insulating layer is formed between the sensing pattern and the bridge electrode. The insulating layer may be formed only between the joint of the first pattern and the bridge electrode, or may be formed as a layer covering the entire sensing pattern. In the case of a layer covering the entire sensing pattern, the bridge electrode can connect the second pattern through a contact hole formed in the insulating layer.
　前記タッチセンサは、感知パターンが形成されたパターン領域と、感知パターンが形成されていない非パターン領域との間の透過率の差、具体的には、これらの領域における屈折率の差によって誘発される光透過率の差を適切に補償するための手段として基板と電極の間に光学調節層をさらに含むことができる。該光学調節層は、無機絶縁物質又は有機絶縁物質を含むことができる。光学調節層は光硬化性有機バインダー及び溶剤を含む光硬化組成物を基板上にコーティングして形成することができる。前記光硬化組成物は無機粒子をさらに含むことができる。前記無機粒子によって光学調節層の屈折率を高くすることができる。
　前記光硬化性有機バインダーは、本発明の効果を損ねない範囲で、例えば、アクリレート系単量体、スチレン系単量体、カルボン酸系単量体などの各単量体の共重合体を含むことができる。前記光硬化性有機バインダーは、例えば、エポキシ基含有繰り返し単位、アクリレート繰り返し単位、カルボン酸繰り返し単位などの互いに異なる各繰り返し単位を含む共重合体であってもよい。
　前記無機粒子としては、例えば、ジルコニア粒子、チタニア粒子、アルミナ粒子などが挙げられる。
　前記光硬化組成物は、光重合開始剤、重合性モノマー、硬化補助剤などの各添加剤をさらに含むこともできる。 The touch sensor is induced by a difference in transmittance between a pattern region in which a sensing pattern is formed and a non-pattern region in which a sensing pattern is not formed, specifically, a difference in refractive index in these regions. An optical adjustment layer may be further included between the substrate and the electrode as a means for appropriately compensating for the difference in light transmittance. The optical control layer may contain an inorganic insulating material or an organic insulating material. The optical control layer can be formed by coating a photocurable composition containing a photocurable organic binder and a solvent on a substrate. The photocurable composition may further contain inorganic particles. The refractive index of the optical control layer can be increased by the inorganic particles.
The photocurable organic binder contains a copolymer of each monomer such as an acrylate-based monomer, a styrene-based monomer, and a carboxylic acid-based monomer, as long as the effects of the present invention are not impaired. be able to. The photocurable organic binder may be, for example, a copolymer containing different repeating units such as an epoxy group-containing repeating unit, an acrylate repeating unit, and a carboxylic acid repeating unit.
Examples of the inorganic particles include zirconia particles, titania particles, alumina particles and the like.
The photocuring composition may further contain additives such as a photopolymerization initiator, a polymerizable monomer, and a curing aid.
　〔接着層〕
　前記フレキシブル表示装置用積層体を形成する、ウインドウフィルム、円偏光板、タッチセンサなどの各層並びに各層を構成する、直線偏光板、λ／４位相差板等のフィルム部材は接着剤によって接合することができる。該接着剤としては、水系接着剤、有機溶剤系、無溶剤系接着剤、固体接着剤、溶剤揮散型接着剤、水系溶剤揮散型接着剤、湿気硬化型接着剤、加熱硬化型接着剤、嫌気硬化型、活性エネルギー線硬化型接着剤、硬化剤混合型接着剤、熱溶融型接着剤、感圧型接着剤、感圧型粘着剤、再湿型接着剤等、通常使用されている接着剤等を用いることができ、好ましくは水系溶剤揮散型接着剤、活性エネルギー線硬化型接着剤、粘着剤を用いることができる。接着剤層の厚さは、求められる接着力等に応じて適宜調節することができ、好ましくは０．０１～５００μｍ、より好ましくは０．１～３００μｍである。前記フレキシブル表示装置用積層体には、複数の接着層が存在するが、それぞれの厚さや種類は、同一であっても異なっていてもよい。 [Adhesive layer]
Each layer of the window film, circularly polarizing plate, touch sensor, etc., which forms the laminated body for the flexible display device, and the film members such as the linear polarizing plate, λ / 4 retardation plate, etc., which form each layer, are joined by an adhesive. Can be done. Examples of the adhesive include water-based adhesives, organic solvent-based adhesives, solvent-free adhesives, solid adhesives, solvent volatilization adhesives, water-based solvent volatilization adhesives, moisture-curable adhesives, heat-curable adhesives, and anaerobic adhesives. Curable type, active energy ray curable type adhesive, hardener mixed type adhesive, heat melt type adhesive, pressure sensitive type adhesive, pressure sensitive type adhesive, rewet type adhesive, etc., commonly used adhesives, etc. It can be used, and preferably an aqueous solvent volatilization type adhesive, an active energy ray-curable adhesive, and a pressure-sensitive adhesive can be used. The thickness of the adhesive layer can be appropriately adjusted according to the required adhesive force and the like, and is preferably 0.01 to 500 μm, more preferably 0.1 to 300 μm. The laminated body for a flexible display device has a plurality of adhesive layers, and the thickness and type of each may be the same or different.
　前記水系溶剤揮散型接着剤としては、ポリビニルアルコール系ポリマー、でんぷん等の水溶性ポリマー、エチレン－酢酸ビニル系エマルジョン、スチレン－ブタジエン系エマルジョン等水分散状態のポリマーを主剤ポリマーとして使用することができる。前記主剤ポリマーと水とに加えて、架橋剤、シラン系化合物、イオン性化合物、架橋触媒、酸化防止剤、染料、顔料、無機フィラー、有機溶剤等を配合してもよい。前記水系溶剤揮散型接着剤によって接着する場合、前記水系溶剤揮散型接着剤を被接着層間に注入して被着層を貼合した後、乾燥させることで接着性を付与することができる。前記水系溶剤揮散型接着剤を用いる場合、その接着層の厚さは、好ましくは０．０１～１０μｍ、より好ましくは０．１～１μｍである。前記水系溶剤揮散型接着剤を複数層に用いる場合、それぞれの層の厚さや種類は同一であっても異なっていてもよい。 As the water-based solvent volatilization type adhesive, a polyvinyl alcohol-based polymer, a water-soluble polymer such as starch, an ethylene-vinyl acetate-based emulsion, a styrene-butadiene-based emulsion, or the like in an aqueous-dispersed state can be used as the main polymer. In addition to the main polymer and water, a cross-linking agent, a silane compound, an ionic compound, a cross-linking catalyst, an antioxidant, a dye, a pigment, an inorganic filler, an organic solvent and the like may be blended. When adhering with the water-based solvent volatilization type adhesive, the water-based solvent volatilization type adhesive can be injected between the layers to be adhered, the adherend layers are bonded, and then dried to impart adhesiveness. When the water-based solvent volatilization type adhesive is used, the thickness of the adhesive layer is preferably 0.01 to 10 μm, more preferably 0.1 to 1 μm. When the water-based solvent volatilization type adhesive is used in a plurality of layers, the thickness and type of each layer may be the same or different.
　前記活性エネルギー線硬化型接着剤は、活性エネルギー線を照射して接着剤層を形成する反応性材料を含む活性エネルギー線硬化組成物の硬化により形成することができる。前記活性エネルギー線硬化組成物は、ハードコート組成物に含まれるものと同様のラジカル重合性化合物及びカチオン重合性化合物の少なくとも１種の重合物を含有することができる。前記ラジカル重合性化合物は、ハードコート組成物におけるラジカル重合性化合物と同じ化合物を用いることができる。
　前記カチオン重合性化合物は、ハードコート組成物におけるカチオン重合性化合物と同じ化合物を用いることができる。
　活性エネルギー線硬化組成物に用いられるカチオン重合性化合物としては、エポキシ化合物が好ましい。接着剤組成物としての粘度を下げるために単官能の化合物を反応性希釈剤として含むことも好ましい。 The active energy ray-curable adhesive can be formed by curing an active energy ray-curable composition containing a reactive material that is irradiated with active energy rays to form an adhesive layer. The active energy ray-curable composition can contain at least one polymer of a radical-polymerizable compound and a cationically polymerizable compound similar to those contained in the hard coat composition. As the radically polymerizable compound, the same compound as the radically polymerizable compound in the hard coat composition can be used.
As the cationically polymerizable compound, the same compound as the cationically polymerizable compound in the hard coat composition can be used.
As the cationically polymerizable compound used in the active energy ray-curing composition, an epoxy compound is preferable. It is also preferable to include a monofunctional compound as a reactive diluent in order to reduce the viscosity of the adhesive composition.
　活性エネルギー線組成物は、粘度を低下させるために、単官能の化合物を含むことができる。該単官能の化合物としては、１分子中に１個の（メタ）アクリロイル基を有するアクリレート系単量体や、１分子中に１個のエポキシ基又はオキセタニル基を有する化合物、例えば、グリシジル（メタ）アクリレートなどが挙げられる。
　活性エネルギー線組成物は、さらに重合開始剤を含むことができる。該重合開始剤としては、ラジカル重合開始剤、カチオン重合開始剤、ラジカル及びカチオン重合開始剤等が挙げられ、これらは適宜選択して用いられる。これらの重合開始剤は、活性エネルギー線照射及び加熱の少なくとも一種により分解されて、ラジカル又はカチオンを発生してラジカル重合とカチオン重合を進行させるものである。ハードコート組成物の記載の中で活性エネルギー線照射によりラジカル重合又はカチオン重合の内の少なくともいずれか開始することができる開始剤を使用することができる。
　前記活性エネルギー線硬化組成物はさらに、イオン捕捉剤、酸化防止剤、連鎖移動剤、密着付与剤、熱可塑性樹脂、充填剤、流動粘度調整剤、可塑剤、消泡剤溶剤、添加剤、溶剤を含むことができる。前記活性エネルギー線硬化型接着剤によって２つの被接着層を接着する場合、前記活性エネルギー線硬化組成物を被接着層のいずれか一方又は両方に塗布後、貼合し、いずれかの被着層又は両方の被接着層に活性エネルギー線を照射して硬化させることにより、で接着することができる。前記活性エネルギー線硬化型接着剤を用いる場合、その接着層の厚さは、好ましくは０．０１～２０μｍ、より好ましくは０．１～１０μｍである。前記活性エネルギー線硬化型接着剤を複数の接着層形成に用いる場合、それぞれの層の厚さや種類は同一であっても異なっていてもよい。 The active energy ray composition can contain a monofunctional compound in order to reduce the viscosity. Examples of the monofunctional compound include an acrylate-based monomer having one (meth) acryloyl group in one molecule, and a compound having one epoxy group or oxetanyl group in one molecule, for example, glycidyl (meth). ) Examples include acrylate.
The active energy ray composition can further contain a polymerization initiator. Examples of the polymerization initiator include radical polymerization initiators, cationic polymerization initiators, radicals and cationic polymerization initiators, and these are appropriately selected and used. These polymerization initiators are decomposed by at least one of active energy ray irradiation and heating to generate radicals or cations to promote radical polymerization and cation polymerization. In the description of the hard coat composition, an initiator that can initiate at least one of radical polymerization or cationic polymerization by irradiation with active energy rays can be used.
The active energy ray-curing composition further comprises an ion trapping agent, an antioxidant, a chain transfer agent, an adhesion imparting agent, a thermoplastic resin, a filler, a fluid viscosity modifier, a plasticizer, a defoaming agent solvent, an additive, and a solvent. Can be included. When two layers to be adhered are bonded by the active energy ray-curable adhesive, the active energy ray-curable composition is applied to either or both of the layers to be adhered, and then bonded to each layer. Alternatively, both layers to be adhered can be adhered by irradiating them with active energy rays and curing them. When the active energy ray-curable adhesive is used, the thickness of the adhesive layer is preferably 0.01 to 20 μm, more preferably 0.1 to 10 μm. When the active energy ray-curable adhesive is used for forming a plurality of adhesive layers, the thickness and type of the respective layers may be the same or different.
　前記粘着剤としては、主剤ポリマーに応じて、アクリル系粘着剤、ウレタン系粘着剤、ゴム系粘着剤、シリコーン系粘着剤等に分類され何れを使用することもできる。粘着剤には主剤ポリマーに加えて、架橋剤、シラン系化合物、イオン性化合物、架橋触媒、酸化防止剤、粘着付与剤、可塑剤、染料、顔料、無機フィラー等を配合してもよい。前記粘着剤を構成する各成分を溶剤に溶解・分散させて粘着剤組成物を得て、該粘着剤組成物を基材上に塗布した後に乾燥させることで、粘着剤層接着層が形成される。粘着層は直接形成されてもよいし、別途基材に形成したものを転写することもできる。接着前の粘着面をカバーするためには離型フィルムを使用することも好ましい。前記活性エネルギー線硬化型接着剤を用いる場合、その接着層の厚さは、好ましくは０．１～５００μｍ、より好ましくは１～３００μｍである。前記粘着剤を複数層用いる場合には、それぞれの層の厚さや種類は同一であっても異なっていてもよい。 The pressure-sensitive adhesive is classified into an acrylic pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, a silicone-based pressure-sensitive adhesive, and the like according to the main polymer, and any of them can be used. In addition to the main polymer, the pressure-sensitive adhesive may contain a cross-linking agent, a silane compound, an ionic compound, a cross-linking catalyst, an antioxidant, a tackifier, a plasticizing agent, a dye, a pigment, an inorganic filler and the like. A pressure-sensitive adhesive layer is formed by dissolving and dispersing each component constituting the pressure-sensitive adhesive in a solvent to obtain a pressure-sensitive adhesive composition, applying the pressure-sensitive adhesive composition onto a substrate, and then drying the mixture. To. The adhesive layer may be directly formed, or a separately formed base material may be transferred. It is also preferable to use a release film to cover the adhesive surface before bonding. When the active energy ray-curable adhesive is used, the thickness of the adhesive layer is preferably 0.1 to 500 μm, more preferably 1 to 300 μm. When a plurality of layers of the pressure-sensitive adhesive are used, the thickness and type of the respective layers may be the same or different.
　〔遮光パターン〕
　前記遮光パターンは、前記フレキシブル表示装置のベゼル又はハウジングの少なくとも一部として適用することができる。遮光パターンによって前記フレキシブル表示装置の辺縁部に配置される配線が隠されて視認されにくくすることで、画像の視認性が向上する。前記遮光パターンは単層又は複層の形態であってもよい。遮光パターンのカラーは特に制限されることはなく、黒色、白色、金属色などの多様なカラーであってもよい。遮光パターンはカラーを具現するための顔料と、アクリル系樹脂、エステル系樹脂、エポキシ系樹脂、ポリウレタン、シリコーンなどの高分子で形成することができる。これらの単独又は２種類以上の混合物で使用することもできる。前記遮光パターンは、印刷、リソグラフィ、インクジェットなど各種の方法にて形成することができる。遮光パターンの厚さは、好ましくは１～１００μｍ、より好ましくは２～５０μｍである。また、遮光パターンの厚さ方向に傾斜等の形状を付与することも好ましい。 [Shading pattern]
The shading pattern can be applied as at least part of the bezel or housing of the flexible display device. The light-shielding pattern hides the wiring arranged at the edge of the flexible display device to make it difficult to see, thereby improving the visibility of the image. The shading pattern may be in the form of a single layer or multiple layers. The color of the light-shielding pattern is not particularly limited, and may be various colors such as black, white, and metallic. The light-shielding pattern can be formed of a pigment for embodying color and a polymer such as an acrylic resin, an ester resin, an epoxy resin, polyurethane, or silicone. They can also be used alone or in mixtures of two or more. The shading pattern can be formed by various methods such as printing, lithography, and inkjet. The thickness of the shading pattern is preferably 1 to 100 μm, more preferably 2 to 50 μm. It is also preferable to give a shape such as an inclination in the thickness direction of the light-shielding pattern.
　以下、実施例及び比較例に基づいて本発明をより具体的に説明するが、本発明は以下の実施例に限定されるものではない。まず測定及び評価方法について説明する。 Hereinafter, the present invention will be described in more detail based on Examples and Comparative Examples, but the present invention is not limited to the following Examples. First, the measurement and evaluation methods will be described.
　＜耐力＞
　実施例及び比較例において得られた光学フィルムの耐力を（株）島津製作所製「オートグラフＡＧ－ＩＳ」を用いて測定した。より詳細には縦横１０ｍｍ幅のフィルムを作製し、チャック間距離５０ｍｍ、引張速度１０ｍｍ／分の条件で応力－歪曲線（Ｓ－Ｓ曲線）を測定した。
１．Ｓ－Ｓ曲線のデータ整理
　Ｓ－Ｓ曲線における測定開始点から連続１０点をサンプリングし、最小二乗法により二次関数にフィッティングする。その後、サンプリング範囲１０点の二次関数フィッティングにより上に凸の形状になるまで、測定開始点の左側から１点を除外し右側の１点を追加する。フィッティング関数が上に凸になった時点でデータ整理を終了とする。
２．Ｓ－Ｓ曲線の接線方程式の計算
　前記１．におけるデータのｎ＝ｉ～ｊ番目（ｊ＝２～５０）のデータで最小二乗法により傾きと切片を求める。その後、ｊ－１個の傾きについてｋ番目（ｋ＝１～４８）から４９番目のデータを最小二乗法で１次関数にフィッティングし、歪が０の時の傾きを外挿により求める。得られた４８点の中央値をとり、歪が０のときの直線の傾き（Ｓ－Ｓ曲線接線）と定義する。切片についても同様に計算し、歪が０におけるＳ－Ｓ曲線の接線の方程式を得る。
３．耐力の計算
　前記２．で得られたＳ－Ｓ曲線の歪が０における接線を歪方向に０．２％平行移動する。応力の測定データが、平行移動した直線の応力を上回ったデータの応力値を耐力とする。 <Yield strength>
The proof stress of the optical films obtained in Examples and Comparative Examples was measured using "Autograph AG-IS" manufactured by Shimadzu Corporation. More specifically, a film having a width of 10 mm in length and width was prepared, and a stress-strain curve (SS curve) was measured under the conditions of a distance between chucks of 50 mm and a tensile speed of 10 mm / min.
1. 1. Data arrangement of the SS curve 10 consecutive points are sampled from the measurement start point on the SS curve and fitted to the quadratic function by the least squares method. After that, one point is excluded from the left side of the measurement start point and one point on the right side is added until the shape becomes convex upward by the quadratic function fitting of 10 points in the sampling range. Data organization ends when the fitting function becomes convex upward.
2. Calculation of tangent equations of SS curve 1. The slope and intercept are obtained by the least squares method from the n = i to jth (j = 2 to 50) data of the data in. After that, the kth (k = 1-48) to 49th data for the j-1 slopes are fitted to the linear function by the least squares method, and the slopes when the strain is 0 are obtained by extrapolation. The median of the obtained 48 points is taken and defined as the slope of a straight line (tangent to the SS curve) when the strain is 0. The intercept is calculated in the same way to obtain the tangent equation of the SS curve when the strain is 0.
3. 3. Calculation of yield strength 2. The strain of the SS curve obtained in step 2 translates the tangent line at 0 by 0.2% in the strain direction. The proof stress is the stress value of the data in which the stress measurement data exceeds the stress of the translated straight line.
　＜全光線透過率＞
　ＪＩＳ　Ｋ　７１０５：１９８１に準拠して、スガ試験機（株）製の全自動直読ヘーズコンピュータＨＧＭ－２ＤＰにより、実施例及び比較例で得られた光学フィルムの全光線透過率（Ｔｔ）を測定した。 <Total light transmittance>
In accordance with JIS K 7105: 1981, the total light transmittance (Tt) of the optical films obtained in Examples and Comparative Examples was measured by a fully automatic direct reading haze computer HGM-2DP manufactured by Suga Test Instruments Co., Ltd. ..
　＜ヘーズ（Ｈａｚｅ）＞
　ＪＩＳ　Ｋ　７１３６：２０００に準拠して、実施例及び比較例で得られた光学フィルムを３０ｍｍ×３０ｍｍの大きさにカットし、ヘーズコンピュータ（スガ試験機（株）製、「ＨＧＭ－２ＤＰ」）を用いてヘーズ（％）を測定した。 <Haze>
In accordance with JIS K 7136: 2000, the optical films obtained in Examples and Comparative Examples were cut into a size of 30 mm × 30 mm, and a haze computer (manufactured by Suga Test Instruments Co., Ltd., “HGM-2DP”) was used. Haze (%) was measured using.
　＜ＹＩ値＞
　実施例及び比較例で得られた光学フィルムについて、紫外可視近赤外分光光度計（日本分光（株）製　Ｖ－６７０）を用いて、三刺激値（Ｘ，Ｙ，Ｚ）を求め、下記計算式に代入することにより、ＹＩ値を算出した。
　ＹＩ＝１００×（１．２７６９Ｘ－１．０５９２Ｚ）／Ｙ <YI value>
For the optical films obtained in Examples and Comparative Examples, tristimulus values (X, Y, Z) were obtained using an ultraviolet-visible near-infrared spectrophotometer (V-670 manufactured by JASCO Corporation), and the following The YI value was calculated by substituting it into the calculation formula.
YI = 100 × (1.2769X-1.0592Z) / Y
　＜弾性率＞
　実施例及び比較例において得られた光学フィルムの弾性率を（株）島津製作所製「オートグラフＡＧ－ＩＳ」を用いて測定した。縦横１０ｍｍ幅のフィルムを作製し、チャック間距離５０ｍｍ、引張速度１０ｍｍ／分の条件で応力－歪曲線（Ｓ－Ｓ曲線）を測定し、その傾きから弾性率を算出した。 <Elastic modulus>
The elastic modulus of the optical film obtained in Examples and Comparative Examples was measured using "Autograph AG-IS" manufactured by Shimadzu Corporation. A film having a width of 10 mm in length and width was produced, a stress-strain curve (SS curve) was measured under the conditions of a distance between chucks of 50 mm and a tensile speed of 10 mm / min, and the elastic modulus was calculated from the inclination.
　＜耐折性の評価＞
　ＡＳＴＭ規格Ｄ２１７６－１６に準拠して、実施例及び比較例における光学フィルムの折り曲げ回数を以下のように求めた。該光学フィルムを、ダンベルカッターを用いて１５ｍｍ×１００ｍｍの短冊状にカットした。カットした光学フィルムをＭＩＴ耐折疲労試験機（（株）東洋精機製作所製　型式０５３０）本体にセットして、試験速度１７５ｃｐｍ、折り曲げ角度１３５°、荷重０．７５ｋｇｆ、折り曲げクランプの半径Ｒ＝１ｍｍの条件で、光学フィルムが破断するまでの裏表方向への往復折曲げ回数を測定し、これを折り曲げ回数（耐折回数ともいう）とした。 <Evaluation of folding resistance>
In accordance with ASTM standard D2176-16, the number of times the optical film was bent in Examples and Comparative Examples was determined as follows. The optical film was cut into strips of 15 mm × 100 mm using a dumbbell cutter. The cut optical film is set in the main body of the MIT folding fatigue tester (model 0530 manufactured by Toyo Seiki Seisakusho Co., Ltd.), and the test speed is 175 cpm, the bending angle is 135 °, the load is 0.75 kgf, and the radius of the bending clamp is R = 1 mm. Under the conditions, the number of reciprocating bends in the front and back directions until the optical film broke was measured, and this was defined as the number of bends (also referred to as the number of fold resistance).
　＜Ｍｗの測定＞
　ＧＰＣ測定
（１）前処理方法
　実施例及び比較例で得られたポリアミドイミド樹脂にＤＭＦ溶離液（１０ｍｍｏｌ／Ｌ臭化リチウム添加溶液）を濃度２ｍｇ／ｍＬとなるように加え、８０℃にて３０分間撹拌しながら加熱し、冷却後、０．４５μｍメンブランフィルターでろ過したものを測定溶液とした。
（２）測定条件
カラム：東ソー（株）製ＴＳＫｇｅｌ　α－２５００（（７）７．８ｍｍ径×３００ｍｍ）×１本、α－Ｍ（（１３）７．８ｍｍ径×３００ｍｍ）×２本
溶離液：ＤＭＦ（１０ｍｍｏｌ／Ｌの臭化リチウム添加）
流量：１．０ｍＬ／分
検出器：ＲＩ検出器
カラム温度：４０℃
注入量：１００μＬ
分子量標準：標準ポリスチレン <Measurement of Mw>
GPC measurement (1) Pretreatment method Add DMF eluent (10 mmol / L lithium bromide solution) to the polyamide-imide resin obtained in Examples and Comparative Examples to a concentration of 2 mg / mL, and add 30 at 80 ° C. The solution was heated with stirring for 1 minute, cooled, and filtered through a 0.45 μm membrane filter to prepare a measurement solution.
(2) Measurement condition Column: TSKgel α-2500 manufactured by Tosoh Corporation ((7) 7.8 mm diameter x 300 mm) x 1, α-M ((13) 7.8 mm diameter x 300 mm) x 2 eluent : DMF (10 mmol / L lithium bromide added)
Flow rate: 1.0 mL / min Detector: RI detector Column temperature: 40 ° C
Injection volume: 100 μL
Molecular weight standard: Standard polystyrene
　＜光学フィルムの厚さ＞
　ＡＢＳデジマチックインジケーター（（株）ミツトヨ製、「ＩＤ－Ｃ１１２ＢＳ」）を用いて、実施例及び比較例で得られた光学フィルムの厚さを測定した。 <Thickness of optical film>
The thickness of the optical film obtained in Examples and Comparative Examples was measured using an ABS digital indicator (“ID-C112BS” manufactured by Mitutoyo Co., Ltd.).
　（実施例１）
［ポリアミドイミド樹脂（１）の調製］
　窒素雰囲気下、撹拌翼を備えたセパラブルフラスコに、ＴＦＭＢ及び水分量７００ｐｐｍ以下まで厳密に脱水したＤＭＡｃをＴＦＭＢの固形分が５．１３質量％となるように加え、室温で撹拌しながらＴＦＭＢをＤＭＡｃ中に溶解させた。次に、フラスコに６ＦＤＡ、及びＴＡＨＭＢＰをＴＦＭＢに対してそれぞれ２０．２０ｍｏｌ％ずつになるように添加し、室温で１６時間撹拌した。その後、１０℃に冷却した後に、ＴＰＣをＴＦＭＢに対して２７．２７ｍｏｌ％になるように加え、１０分撹拌後に、さらにＴＰＣをＴＦＭＢに対して２７．２７ｍｏｌ％になるように加え、３０分間撹拌した。その後、はじめに加えたＤＭＡｃと同量のＤＭＡｃを加え、１０分間撹拌した後に、ＴＰＣをＴＦＭＢに対して６．０６ｍｏｌ％になるように加え、２時間撹拌した。次いで、フラスコにジイソプロピルエチルアミン、４－ピコリン、及び無水酢酸を、ＴＦＭＢに対してそれぞれ６０．６１ｍｏｌ％、６０．６１ｍｏｌ％、２８２．８３ｍｏｌ％となるように加え、３０分間撹拌した後、内温を７０℃に昇温し、さらに３時間撹拌し、反応液を得た。
　得られた反応液を室温まで冷却し、該反応液を大量のメタノール中に糸状に投入し、析出した沈殿物を取り出し、メタノール中に６時間浸漬後、メタノールで洗浄した。次に、６０℃にて沈殿物の減圧乾燥を行い、ポリアミドイミド樹脂（１）を得た。得られたポリアミドイミド樹脂（１）のＭｗは、７４８，０００であった。 (Example 1)
[Preparation of Polyamide-imide Resin (1)]
In a nitrogen atmosphere, add TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.13% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc. Next, 6FDA and TAHMBP were added to the flask in an amount of 20.20 mol% each based on TFMB, and the mixture was stirred at room temperature for 16 hours. Then, after cooling to 10 ° C., TPC was added to 27.27 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added to 27.27 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.06 mol% with respect to TFMB, and the mixture was stirred for 2 hours. Next, diisopropylethylamine, 4-picoline, and acetic anhydride were added to the flask so as to be 60.61 mol%, 60.61 mol%, and 282.83 mol%, respectively, with respect to TFMB, and the mixture was stirred for 30 minutes, and then the internal temperature was adjusted. The temperature was raised to 70 ° C., and the mixture was further stirred for 3 hours to obtain a reaction solution.
The obtained reaction solution was cooled to room temperature, the reaction solution was poured into a large amount of methanol in the form of filaments, the precipitated precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 60 ° C. to obtain a polyamide-imide resin (1). The Mw of the obtained polyamide-imide resin (1) was 748,000.
［光学フィルム（１）の製造］
　得られたポリアミドイミド樹脂（１）に、濃度が１０質量％となるようにＤＭＡｃを加え、ポリアミドイミド樹脂ワニス（１）を作製した。得られたポリアミドイミド樹脂ワニス（１）をポリエステル基材（東洋紡（株）製、商品名「Ａ４１００」）の平滑面上に自立膜の厚さが４５μｍとなるようにアプリケーターを用いて塗工し、５０℃で３０分間、次いで１４０℃で１５分間乾燥し、自立膜を得た。自立膜を金枠に固定し、さらに２００℃で６０分間乾燥し、厚さ４０μｍの光学フィルム（１）を得た。 [Manufacturing of optical film (1)]
DMAc was added to the obtained polyamide-imide resin (1) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (1). The obtained polyamide-imide resin varnish (1) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 45 μm. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film. The free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (1) having a thickness of 40 μm.
　（実施例２）
［ポリアミドイミド樹脂（２）の調製］
　窒素雰囲気下、撹拌翼を備えたセパラブルフラスコに、ＴＦＭＢ及び水分量７００ｐｐｍ以下まで厳密に脱水したＤＭＡｃをＴＦＭＢの固形分が５．０８質量％となるように加え、室温で撹拌しながらＴＦＭＢをＤＭＡｃ中に溶解させた。次に、フラスコに６ＦＤＡ、及びＴＡＨＭＢＰをＴＦＭＢに対してそれぞれ２０．６２ｍｏｌ％ずつになるように添加し、室温で１６時間撹拌した。その後、１０℃に冷却した後に、ＴＰＣをＴＦＭＢに対して２７．８４ｍｏｌ％になるように加え、１０分撹拌後に、さらにＴＰＣをＴＦＭＢに対して２７．８４ｍｏｌ％になるように加え、３０分間撹拌した。その後、はじめに加えたＤＭＡｃと同量のＤＭＡｃを加え、１０分間撹拌した後に、ＴＰＣをＴＦＭＢに対して６．１９ｍｏｌ％になるように加え、２時間撹拌した。次いで、フラスコにジイソプロピルエチルアミン、４－ピコリン、及び無水酢酸を、ＴＦＭＢに対してそれぞれ６１．８６ｍｏｌ％、６１．８６ｍｏｌ％、２８８．６６ｍｏｌ％となるように加え、３０分間撹拌した後、内温を７０℃に昇温し、さらに３時間撹拌し、反応液を得た。
　得られた反応液を室温まで冷却し、該反応液を大量のメタノール中に糸状に投入し、析出した沈殿物を取り出し、メタノール中に６時間浸漬後、メタノールで洗浄した。次に、６０℃にて沈殿物の減圧乾燥を行い、ポリアミドイミド樹脂（２）を得た。得られたポリアミドイミド樹脂（２）のＭｗは、４８６，０００であった。 (Example 2)
[Preparation of Polyamide-imide Resin (2)]
In a nitrogen atmosphere, add TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.08% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc. Next, 6FDA and TAHMBP were added to the flask in an amount of 20.62 mol% each based on TFMB, and the mixture was stirred at room temperature for 16 hours. Then, after cooling to 10 ° C., TPC was added to 27.84 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added to 27.84 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.19 mol% with respect to TFMB, and the mixture was stirred for 2 hours. Next, diisopropylethylamine, 4-picoline, and acetic anhydride were added to the flask so as to be 61.86 mol%, 61.86 mol%, and 288.66 mol% with respect to TFMB, respectively, and the mixture was stirred for 30 minutes and then the internal temperature was adjusted. The temperature was raised to 70 ° C., and the mixture was further stirred for 3 hours to obtain a reaction solution.
The obtained reaction solution was cooled to room temperature, the reaction solution was poured into a large amount of methanol in the form of filaments, the precipitated precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 60 ° C. to obtain a polyamide-imide resin (2). The Mw of the obtained polyamide-imide resin (2) was 486,000.
［光学フィルム（２）の製造］
　得られたポリアミドイミド樹脂（２）に、濃度が１０質量％となるようにＤＭＡｃを加え、ポリアミドイミド樹脂ワニス（２）を作製した。得られたポリアミドイミド樹脂ワニス（２）をポリエステル基材（東洋紡（株）製、商品名「Ａ４１００」）の平滑面上に自立膜の厚さが４５μｍとなるようにアプリケーターを用いて塗工し、５０℃で３０分間、次いで１４０℃で１５分間乾燥し、自立膜を得た。自立膜を金枠に固定し、さらに２００℃で６０分間乾燥し、厚さ４０μｍの光学フィルム（２）を得た。 [Manufacturing of optical film (2)]
DMAc was added to the obtained polyamide-imide resin (2) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (2). The obtained polyamide-imide resin varnish (2) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 45 μm. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film. The free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (2) having a thickness of 40 μm.
　（実施例３）
［ポリアミドイミド樹脂（３）の調製］
　窒素雰囲気下、撹拌翼を備えたセパラブルフラスコに、ＴＦＭＢ及び水分量７００ｐｐｍ以下まで厳密に脱水したＤＭＡｃをＴＦＭＢの固形分が５．０８質量％となるように加え、室温で撹拌しながらＴＦＭＢをＤＭＡｃ中に溶解させた。次に、フラスコに６ＦＤＡ、及びＴＡＨＭＢＰをＴＦＭＢに対してそれぞれ２０．６２ｍｏｌ％ずつになるように添加し、室温で１６時間撹拌した。その後、１０℃に冷却した後に、ＴＰＣをＴＦＭＢに対して２７．８４ｍｏｌ％になるように加え、１０分撹拌後に、さらにＴＰＣをＴＦＭＢに対して２７．８４ｍｏｌ％になるように加え、３０分間撹拌した。その後、はじめに加えたＤＭＡｃと同量のＤＭＡｃを加え、１０分間撹拌した後に、ＴＰＣをＴＦＭＢに対して６．１９ｍｏｌ％になるように加え、２時間撹拌した。次いで、フラスコにジイソプロピルエチルアミン、４－ピコリン、及び無水酢酸を、ＴＦＭＢに対してそれぞれ６１．８６ｍｏｌ％、６１．８６ｍｏｌ％、２８８．６６ｍｏｌ％となるように加え、３０分間撹拌した後、内温を７０℃に昇温し、さらに３時間撹拌し、反応液を得た。
　得られた反応液を室温まで冷却し、該反応液を大量のメタノール中に糸状に投入し、析出した沈殿物を取り出し、メタノール中に６時間浸漬後、メタノールで洗浄した。次に、６０℃にて沈殿物の減圧乾燥を行い、ポリアミドイミド樹脂（３）を得た。得られたポリアミドイミド樹脂（３）のＭｗは、２１５，０００であった。 (Example 3)
[Preparation of Polyamide-imide Resin (3)]
In a nitrogen atmosphere, add TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.08% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc. Next, 6FDA and TAHMBP were added to the flask in an amount of 20.62 mol% each based on TFMB, and the mixture was stirred at room temperature for 16 hours. Then, after cooling to 10 ° C., TPC was added to 27.84 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added to 27.84 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.19 mol% with respect to TFMB, and the mixture was stirred for 2 hours. Next, diisopropylethylamine, 4-picoline, and acetic anhydride were added to the flask so as to be 61.86 mol%, 61.86 mol%, and 288.66 mol% with respect to TFMB, respectively, and the mixture was stirred for 30 minutes and then the internal temperature was adjusted. The temperature was raised to 70 ° C., and the mixture was further stirred for 3 hours to obtain a reaction solution.
The obtained reaction solution was cooled to room temperature, the reaction solution was poured into a large amount of methanol in the form of filaments, the precipitated precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 60 ° C. to obtain a polyamide-imide resin (3). The Mw of the obtained polyamide-imide resin (3) was 215,000.
［光学フィルム（３）の製造］
　得られたポリアミドイミド樹脂（３）に、濃度が１０質量％となるようにＤＭＡｃを加え、ポリアミドイミド樹脂ワニス（３）を作製した。得られたポリアミドイミド樹脂ワニス（３）をポリエステル基材（東洋紡（株）製、商品名「Ａ４１００」）の平滑面上に自立膜の厚さが４５μｍとなるようにアプリケーターを用いて塗工し、５０℃で３０分間、次いで１４０℃で１５分間乾燥し、自立膜を得た。自立膜を金枠に固定し、さらに２００℃で６０分間乾燥し、厚さ４０μｍの光学フィルム（３）を得た。 [Manufacturing of optical film (3)]
DMAc was added to the obtained polyamide-imide resin (3) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (3). The obtained polyamide-imide resin varnish (3) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 45 μm. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film. The free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (3) having a thickness of 40 μm.
　（実施例４）
［ポリアミドイミド樹脂（４）の調製］
　窒素雰囲気下、撹拌翼を備えたセパラブルフラスコに、ＴＦＭＢ及び水分量７００ｐｐｍ以下まで厳密に脱水したＤＭＡｃをＴＦＭＢの固形分が５．１６質量％となるように加え、室温で撹拌しながらＴＦＭＢをＤＭＡｃ中に溶解させた。次に、フラスコにＴＡＨＭＢＰをＴＦＭＢに対して３０．６１ｍｏｌ％になるように添加し、室温で１６時間撹拌した。その後、１０℃に冷却した後に、ＴＰＣをＴＦＭＢに対して３２．１４ｍｏｌ％になるように加え、１０分撹拌後に、さらにＴＰＣをＴＦＭＢに対して３２．１４ｍｏｌ％になるように加え、３０分間撹拌した。その後、はじめに加えたＤＭＡｃと同量のＤＭＡｃを加え、１０分間撹拌した後に、ＴＰＣをＴＦＭＢに対して７．１４ｍｏｌ％になるように加え、２時間撹拌した。次いで、フラスコにジイソプロピルエチルアミン、４－ピコリン、及び無水酢酸を、ＴＦＭＢに対してそれぞれ７１．４３ｍｏｌ％、７１．４３ｍｏｌ％、２１４．２９ｍｏｌ％となるように加え、３０分間撹拌した後、内温を７０℃に昇温し、さらに３時間撹拌し、反応液を得た。
　得られた反応液を室温まで冷却し、該反応液を大量のメタノール中に糸状に投入し、析出した沈殿物を取り出し、メタノール中に６時間浸漬後、メタノールで洗浄した。次に、６０℃にて沈殿物の減圧乾燥を行い、ポリアミドイミド樹脂（４）を得た。得られたポリアミドイミド樹脂（４）のＭｗは、７６４，０００であった。 (Example 4)
[Preparation of Polyamide-imide Resin (4)]
In a nitrogen atmosphere, add TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.16% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc. Next, TAHMBP was added to the flask so as to be 30.61 mol% with respect to TFMB, and the mixture was stirred at room temperature for 16 hours. Then, after cooling to 10 ° C., TPC was added so as to be 32.14 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added so as to be 32.14 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 7.14 mol% with respect to TFMB, and the mixture was stirred for 2 hours. Next, diisopropylethylamine, 4-picoline, and acetic anhydride were added to the flask so as to be 71.43 mol%, 71.43 mol%, and 214.29 mol%, respectively, with respect to TFMB, and the mixture was stirred for 30 minutes, and then the internal temperature was adjusted. The temperature was raised to 70 ° C., and the mixture was further stirred for 3 hours to obtain a reaction solution.
The obtained reaction solution was cooled to room temperature, the reaction solution was poured into a large amount of methanol in the form of filaments, the precipitated precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 60 ° C. to obtain a polyamide-imide resin (4). The Mw of the obtained polyamide-imide resin (4) was 764,000.
［光学フィルム（４）の製造］
　得られたポリアミドイミド樹脂（４）に、濃度が１０質量％となるようにＤＭＡｃを加え、ポリアミドイミド樹脂ワニス（４）を作製した。得られたポリアミドイミド樹脂ワニス（４）をポリエステル基材（東洋紡（株）製、商品名「Ａ４１００」）の平滑面上に自立膜の厚さが４５μｍとなるようにアプリケーターを用いて塗工し、５０℃で３０分間、次いで１４０℃で１５分間乾燥し、自立膜を得た。自立膜を金枠に固定し、さらに２００℃で６０分間乾燥し、厚さ４０μｍの光学フィルム（４）を得た。 [Manufacturing of optical film (4)]
DMAc was added to the obtained polyamide-imide resin (4) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (4). The obtained polyamide-imide resin varnish (4) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 45 μm. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film. The free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (4) having a thickness of 40 μm.
　（実施例５）
［ポリアミドイミド樹脂（５）の調製］
　窒素雰囲気下、撹拌翼を備えたセパラブルフラスコに、ＴＦＭＢ及び水分量７００ｐｐｍ以下まで厳密に脱水したＤＭＡｃをＴＦＭＢの固形分が４．８６質量％となるように加え、室温で撹拌しながらＴＦＭＢをＤＭＡｃ中に溶解させた。次に、フラスコにＴＡＨＭＢＰをＴＦＭＢに対して４０．８２ｍｏｌ％になるように添加し、室温で１６時間撹拌した。その後、１０℃に冷却した後に、ＴＰＣをＴＦＭＢに対して２７．５５ｍｏｌ％になるように加え、１０分撹拌後に、さらにＴＰＣをＴＦＭＢに対して２７．５５ｍｏｌ％になるように加え、３０分間撹拌した。その後、はじめに加えたＤＭＡｃと同量のＤＭＡｃを加え、１０分間撹拌した後に、ＴＰＣをＴＦＭＢに対して６．１２ｍｏｌ％になるように加え、２時間撹拌した。次いで、フラスコにジイソプロピルエチルアミン、４－ピコリン、及び無水酢酸を、ＴＦＭＢに対してそれぞれ６１．２２ｍｏｌ％、６１．２２ｍｏｌ％、２８５．７１ｍｏｌ％となるように加え、３０分間撹拌した後、内温を７０℃に昇温し、さらに３時間撹拌し、反応液を得た。
　得られた反応液を室温まで冷却し、該反応液を大量のメタノール中に糸状に投入し、析出した沈殿物を取り出し、メタノール中に６時間浸漬後、メタノールで洗浄した。次に、６０℃にて沈殿物の減圧乾燥を行い、ポリアミドイミド樹脂（５）を得た。得られたポリアミドイミド樹脂（５）のＭｗは、６１３，０００であった。 (Example 5)
[Preparation of Polyamide-imide Resin (5)]
In a nitrogen atmosphere, add TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 4.86% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc. Next, TAHMBP was added to the flask so as to be 40.82 mol% with respect to TFMB, and the mixture was stirred at room temperature for 16 hours. Then, after cooling to 10 ° C., TPC was added so as to be 27.55 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added so as to be 27.55 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.12 mol% with respect to TFMB, and the mixture was stirred for 2 hours. Next, diisopropylethylamine, 4-picoline, and acetic anhydride were added to the flask so as to be 61.22 mol%, 61.22 mol%, and 285.71 mol%, respectively, with respect to TFMB, and the mixture was stirred for 30 minutes, and then the internal temperature was adjusted. The temperature was raised to 70 ° C., and the mixture was further stirred for 3 hours to obtain a reaction solution.
The obtained reaction solution was cooled to room temperature, the reaction solution was poured into a large amount of methanol in the form of filaments, the precipitated precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 60 ° C. to obtain a polyamide-imide resin (5). The Mw of the obtained polyamide-imide resin (5) was 613,000.
［光学フィルム（５）の製造］
　得られたポリアミドイミド樹脂（５）に、濃度が１０質量％となるようにＤＭＡｃを加え、ポリアミドイミド樹脂ワニス（５）を作製した。得られたポリアミドイミド樹脂ワニス（５）をポリエステル基材（東洋紡（株）製、商品名「Ａ４１００」）の平滑面上に自立膜の厚さが４５μｍとなるようにアプリケーターを用いて塗工し、５０℃で３０分間、次いで１４０℃で１５分間乾燥し、自立膜を得た。自立膜を金枠に固定し、さらに２００℃で６０分間乾燥し、厚さ４０μｍの光学フィルム（５）を得た。 [Manufacturing of optical film (5)]
DMAc was added to the obtained polyamide-imide resin (5) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (5). The obtained polyamide-imide resin varnish (5) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 45 μm. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film. The free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (5) having a thickness of 40 μm.
　（実施例６）
［ポリアミドイミド樹脂（６）の調製］
　窒素雰囲気下、撹拌翼を備えたセパラブルフラスコに、ＴＦＭＢ及び水分量７００ｐｐｍ以下まで厳密に脱水したＤＭＡｃをＴＦＭＢの固形分が５．２９質量％となるように加え、室温で撹拌しながらＴＦＭＢをＤＭＡｃ中に溶解させた。次に、フラスコに６ＦＤＡ、及びＴＡＨＭＢＰをＴＦＭＢに対してそれぞれ１０．２０ｍｏｌ％、２０．４１ｍｏｌ％になるように添加し、室温で１６時間撹拌した。その後、１０℃に冷却した後に、ＴＰＣをＴＦＭＢに対して３２．１４ｍｏｌ％になるように加え、１０分撹拌後に、さらにＴＰＣをＴＦＭＢに対して３２．１４ｍｏｌ％になるように加え、３０分間撹拌した。その後、はじめに加えたＤＭＡｃと同量のＤＭＡｃを加え、１０分間撹拌した後に、ＴＰＣをＴＦＭＢに対して７．１４ｍｏｌ％になるように加え、２時間撹拌した。次いで、フラスコにジイソプロピルエチルアミン、４－ピコリン、及び無水酢酸を、ＴＦＭＢに対してそれぞれ７１．４３ｍｏｌ％、７１．４３ｍｏｌ％、２１４．２９ｍｏｌ％となるように加え、３０分間撹拌した後、内温を７０℃に昇温し、さらに３時間撹拌し、反応液を得た。
　得られた反応液を室温まで冷却し、該反応液を大量のメタノール中に糸状に投入し、析出した沈殿物を取り出し、メタノール中に６時間浸漬後、メタノールで洗浄した。次に、６０℃にて沈殿物の減圧乾燥を行い、ポリアミドイミド樹脂（６）を得た。得られたポリアミドイミド樹脂（６）のＭｗは、７５１，０００であった。 (Example 6)
[Preparation of Polyamide-imide Resin (6)]
In a nitrogen atmosphere, add TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.29% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc. Next, 6FDA and TAHMBP were added to the flask so as to be 10.20 mol% and 20.41 mol%, respectively, based on TFMB, and the mixture was stirred at room temperature for 16 hours. Then, after cooling to 10 ° C., TPC was added so as to be 32.14 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added so as to be 32.14 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 7.14 mol% with respect to TFMB, and the mixture was stirred for 2 hours. Next, diisopropylethylamine, 4-picoline, and acetic anhydride were added to the flask so as to be 71.43 mol%, 71.43 mol%, and 214.29 mol%, respectively, with respect to TFMB, and the mixture was stirred for 30 minutes, and then the internal temperature was adjusted. The temperature was raised to 70 ° C., and the mixture was further stirred for 3 hours to obtain a reaction solution.
The obtained reaction solution was cooled to room temperature, the reaction solution was poured into a large amount of methanol in the form of filaments, the precipitated precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 60 ° C. to obtain a polyamide-imide resin (6). The Mw of the obtained polyamide-imide resin (6) was 751,000.
［光学フィルム（６）の製造］
　得られたポリアミドイミド樹脂（６）に、濃度が１０質量％となるようにＤＭＡｃを加え、ポリアミドイミド樹脂ワニス（６）を作製した。得られたポリアミドイミド樹脂ワニス（６）をポリエステル基材（東洋紡（株）製、商品名「Ａ４１００」）の平滑面上に自立膜の厚さが４５μｍとなるようにアプリケーターを用いて塗工し、５０℃で３０分間、次いで１４０℃で１５分間乾燥し、自立膜を得た。自立膜を金枠に固定し、さらに２００℃で６０分間乾燥し、厚さ４０μｍの光学フィルム（６）を得た。 [Manufacturing of optical film (6)]
DMAc was added to the obtained polyamide-imide resin (6) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (6). The obtained polyamide-imide resin varnish (6) was coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film was 45 μm. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film. The free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (6) having a thickness of 40 μm.
　（比較例１）
　［ポリアミドイミド樹脂（７）の調製］
　窒素雰囲気下、撹拌翼を備えたセパラブルフラスコに、ＴＦＭＢ及び水分量７００ｐｐｍ以下まで厳密に脱水したＤＭＡｃをＴＦＭＢの固形分が５．２７質量％となるように加え、室温で撹拌しながらＴＦＭＢをＤＭＡｃ中に溶解させた。次に、フラスコに６ＦＤＡ、及び無水トリメリット酸と４，４’－ビフェノールとのエステル化物（ＴＡ４４ＢＰ）をＴＦＭＢに対してそれぞれ２０．１０ｍｏｌ％ずつになるように添加し、室温で１６時間撹拌した。その後、１０℃に冷却した後に、ＴＰＣをＴＦＭＢに対して２７．１４ｍｏｌ％になるように加え、１０分撹拌後に、さらにＴＰＣをＴＦＭＢに対して２７．１４ｍоｌ％になるように加え、３０分間撹拌した。その後、はじめに加えたＤＭＡｃと同量のＤＭＡｃを加え、１０分間撹拌した後に、ＴＰＣをＴＦＭＢに対して６．０３ｍｏｌ％になるように加え、２時間撹拌した。次いで、フラスコにジイソプロピルエチルアミン、４－ピコリン、及び無水酢酸をそれぞれＴＦＭＢに対して６０．３０ｍｏｌ％、６０．３０ｍｏｌ％、２８１．４１ｍｏｌ％となるように加え、３０分間撹拌した後、内温を７０℃に昇温し、さらに３時間撹拌し、反応液を得た。
　得られた反応液を室温まで冷却し、該反応液を大量のメタノール中に糸状に投入し、析出した沈殿物を取り出し、メタノール中に６時間浸漬後、メタノールで洗浄した。次に、６０℃にて沈殿物の減圧乾燥を行い、ポリアミドイミド樹脂（７）を得た。得られたポリアミドイミド樹脂（７）のＭｗは、１３９，０００であった。 (Comparative Example 1)
[Preparation of Polyamide-imide Resin (7)]
In a nitrogen atmosphere, add TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.27% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc. Next, 6FDA and an esterified product of trimellitic anhydride and 4,4'-biphenol (TA44BP) were added to the flask in an amount of 20.10 mol% each based on TFMB, and the mixture was stirred at room temperature for 16 hours. .. Then, after cooling to 10 ° C., TPC was added to 27.14 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added to 27.14 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.03 mol% with respect to TFMB, and the mixture was stirred for 2 hours. Next, diisopropylethylamine, 4-picoline, and acetic anhydride were added to the flask so as to be 60.30 mol%, 60.30 mol%, and 281.41 mol% with respect to TFMB, respectively, and the mixture was stirred for 30 minutes, and then the internal temperature was 70. The temperature was raised to ° C. and the mixture was further stirred for 3 hours to obtain a reaction solution.
The obtained reaction solution was cooled to room temperature, the reaction solution was poured into a large amount of methanol in the form of filaments, the precipitated precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 60 ° C. to obtain a polyamide-imide resin (7). The Mw of the obtained polyamide-imide resin (7) was 139,000.
［光学フィルム（７）の製造］
　得られたポリアミドイミド樹脂（７）に、濃度が１０質量％となるようにＤＭＡｃを加え、ポリアミドイミド樹脂ワニス（７）を作製した。得られたポリアミドイミド樹脂ワニス（７）をポリエステル基材（東洋紡（株）製、商品名「Ａ４１００」）の平滑面上に自立膜の厚さが５５μｍとなるようにアプリケーターを用いて塗工し、５０℃で３０分間、次いで１４０℃で１５分間乾燥し、自立膜を得た。自立膜を金枠に固定し、さらに２００℃で６０分間乾燥し、厚さ５０μｍの光学フィルム（７）を得た。 [Manufacturing of optical film (7)]
DMAc was added to the obtained polyamide-imide resin (7) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (7). The obtained polyamide-imide resin varnish (7) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 55 μm. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film. The free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (7) having a thickness of 50 μm.
　（比較例２）
［ポリアミドイミド樹脂（８）の調製］
　窒素雰囲気下、撹拌翼を備えたセパラブルフラスコに、ＴＦＭＢ及び水分量７００ｐｐｍ以下まで厳密に脱水したＤＭＡｃをＴＦＭＢの固形分が５．３５質量％となるように加え、室温で撹拌しながらＴＦＭＢをＤＭＡｃ中に溶解させた。次に、フラスコに６ＦＤＡをＴＦＭＢに対して４１．２４ｍｏｌ％になるように添加し、室温で１６時間撹拌した。その後、１０℃に冷却した後に、ＴＰＣをＴＦＭＢに対して２７．８４ｍｏｌ％になるように加え、１０分撹拌後に、さらにＴＰＣをＴＦＭＢに対して２７．８４ｍｏｌ％になるように加え、３０分間撹拌した。その後、はじめに加えたＤＭＡｃと同量のＤＭＡｃを加え、１０分間撹拌した後に、ＴＰＣをＴＦＭＢに対して６．１９ｍｏｌ％になるように加え、２時間撹拌した。次いで、フラスコにジイソプロピルエチルアミン、４－ピコリン、及び無水酢酸をそれぞれＴＦＭＢに対して６１．８６ｍｏｌ％、６１．８６ｍｏｌ％、２８８．６６ｍｏｌ％となるように加え、３０分間撹拌した後、内温を７０℃に昇温し、さらに３時間撹拌し、反応液を得た。
　得られた反応液を室温まで冷却し、該反応液を大量のメタノール中に糸状に投入し、析出した沈殿物を取り出し、メタノール中に６時間浸漬後、メタノールで洗浄した。次に、６０℃にて沈殿物の減圧乾燥を行い、ポリアミドイミド樹脂（８）を得た。得られたポリアミドイミド樹脂（８）のＭｗは、１７４，０００であった。 (Comparative Example 2)
[Preparation of Polyamide-imide Resin (8)]
In a nitrogen atmosphere, add TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.35% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc. Next, 6 FDA was added to the flask so as to be 41.24 mol% with respect to TFMB, and the mixture was stirred at room temperature for 16 hours. Then, after cooling to 10 ° C., TPC was added to 27.84 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added to 27.84 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the initially added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 6.19 mol% with respect to TFMB, and the mixture was stirred for 2 hours. Next, diisopropylethylamine, 4-picoline, and acetic anhydride were added to the flask so as to be 61.86 mol%, 61.86 mol%, and 288.66 mol%, respectively, with respect to TFMB, and after stirring for 30 minutes, the internal temperature was 70. The temperature was raised to ° C., and the mixture was further stirred for 3 hours to obtain a reaction solution.
The obtained reaction solution was cooled to room temperature, the reaction solution was poured into a large amount of methanol in the form of filaments, the precipitated precipitate was taken out, immersed in methanol for 6 hours, and then washed with methanol. Next, the precipitate was dried under reduced pressure at 60 ° C. to obtain a polyamide-imide resin (8). The Mw of the obtained polyamide-imide resin (8) was 174,000.
［光学フィルム（８）の製造］
　得られたポリアミドイミド樹脂（８）に、濃度が１０質量％となるようにＤＭＡｃを加え、ポリアミドイミド樹脂ワニス（８）を作製した。得られたポリアミドイミド樹脂ワニス（８）をポリエステル基材（東洋紡（株）製、商品名「Ａ４１００」）の平滑面上に自立膜の厚さが５５μｍとなるようにアプリケーターを用いて塗工し、５０℃で３０分間、次いで１４０℃で１５分間乾燥し、自立膜を得た。自立膜を金枠に固定し、さらに２００℃で６０分間乾燥し、厚さ５０μｍの光学フィルム（８）を得た。 [Manufacturing of optical film (8)]
DMAc was added to the obtained polyamide-imide resin (8) so as to have a concentration of 10% by mass to prepare a polyamide-imide resin varnish (8). The obtained polyamide-imide resin varnish (8) is coated on a smooth surface of a polyester base material (manufactured by Toyobo Co., Ltd., trade name "A4100") using an applicator so that the thickness of the free-standing film is 55 μm. , 50 ° C. for 30 minutes, then 140 ° C. for 15 minutes to obtain a free-standing film. The free-standing film was fixed to a gold frame and further dried at 200 ° C. for 60 minutes to obtain an optical film (8) having a thickness of 50 μm.
　（比較例３）
［ポリアミドイミド樹脂（９）の調製］
　窒素雰囲気下、撹拌翼を備えたセパラブルフラスコに、ＴＦＭＢ及び水分量７００ｐｐｍ以下まで厳密に脱水したＤＭＡｃをＴＦＭＢの固形分が５．８１質量％となるように加え、室温で撹拌しながらＴＦＭＢをＤＭＡｃ中に溶解させた。次に、フラスコに６ＦＤＡをＴＦＭＢに対して２０．４１ｍｏｌ％になるように添加し、室温で１６時間撹拌した。その後、１０℃に冷却した後に、ＴＰＣをＴＦＭＢに対して３６．７３ｍｏｌ％になるように加え、１０分撹拌後に、さらにＴＰＣをＴＦＭＢに対して３６．７３ｍｏｌ％になるように加え、３０分間撹拌した。その後、はじめに加えたＤＭＡｃと同量のＤＭＡｃを加え、１０分間撹拌した後に、ＴＰＣをＴＦＭＢに対して８．１６ｍｏｌ％になるように加え、２時間撹拌したが、途中で粘度上昇が顕著となり、溶液が寒天状となった。その後の合成操作が困難となったため、樹脂合成を断念した。 (Comparative Example 3)
[Preparation of Polyamide-imide Resin (9)]
In a nitrogen atmosphere, add TFMB and DMAc strictly dehydrated to a water content of 700 ppm or less to a separable flask equipped with a stirring blade so that the solid content of TFMB is 5.81% by mass, and add TFMB while stirring at room temperature. It was dissolved in DMAc. Next, 6 FDA was added to the flask so as to be 20.41 mol% with respect to TFMB, and the mixture was stirred at room temperature for 16 hours. Then, after cooling to 10 ° C., TPC was added so as to be 36.73 mol% with respect to TFMB, and after stirring for 10 minutes, TPC was further added so as to be 36.73 mol% with respect to TFMB, and the mixture was stirred for 30 minutes. did. Then, the same amount of DMAc as the first added DMAc was added, and after stirring for 10 minutes, TPC was added so as to be 8.16 mol% with respect to TFMB, and the mixture was stirred for 2 hours. The solution became agar-like. Since the subsequent synthesis operation became difficult, resin synthesis was abandoned.
　実施例１～６並びに比較例１及び２で得られた光学フィルムについて、耐力、全光線透過率、ヘーズ、ＹＩ値及び弾性率の測定、並びに耐折性評価を行った結果を表１に示した。なお、比較例３は合成中に不溶となり、ポリアミドイミド樹脂を合成できなかったため、測定及び評価を行えなかった。 Table 1 shows the results of measuring the proof stress, total light transmittance, haze, YI value and elastic modulus, and evaluating the folding resistance of the optical films obtained in Examples 1 to 6 and Comparative Examples 1 and 2. It was. In Comparative Example 3, the polyamide-imide resin could not be synthesized because it became insoluble during the synthesis, so that the measurement and evaluation could not be performed.
Figure JPOXMLDOC01-appb-T000028
Figure JPOXMLDOC01-appb-T000028
　表１に示される通り、実施例１～６のポリアミドイミド樹脂から形成された光学フィルムは、耐力が高く、かつ優れた光学特性を有することが確認された。これに対して、比較例１及び２のポリアミドイミド樹脂から形成された光学フィルムは、耐力が低いことが確認された。
　したがって、実施例１～６のポリアミドイミド樹脂から形成されたフィルムは、高耐力を有し、かつ、優れた光学特性を有していることがわかった。 As shown in Table 1, it was confirmed that the optical films formed from the polyamide-imide resins of Examples 1 to 6 had high proof stress and excellent optical properties. On the other hand, it was confirmed that the optical films formed from the polyamide-imide resins of Comparative Examples 1 and 2 had low proof stress.
Therefore, it was found that the films formed from the polyamide-imide resins of Examples 1 to 6 had high proof stress and excellent optical properties.

Claims (14)

  1. 　式（１）及び式（２）：
    Figure JPOXMLDOC01-appb-C000001
     ［式（１）及び式（２）中、Ｘ及びＺは、互いに独立に、２価の有機基を表し、Ｙは４価の有機基を表し、＊は結合手を表す］
    で表される構成単位を含み、式（１）中のＹとして、式（３）：
    Figure JPOXMLDOC01-appb-C000002
     ［式（３）中、Ｒ１は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、Ｒ２～Ｒ５は、互いに独立に、水素原子、又はハロゲン原子を有してもよい１価の炭化水素基を表し、ｍは、互いに独立に、０～３の整数を表し、ｎは１～４の整数を表し、＊は結合手を表し、ただし、Ｒ２～Ｒ５を有する少なくとも１つのベンゼン環において、Ｒ２～Ｒ５の少なくとも１つがハロゲン原子を有してもよい１価の炭化水素基である］
    で表される構造を含む、ポリアミドイミド樹脂。     Equation (1) and Equation (2):
    Figure JPOXMLDOC01-appb-C000001
     [In formulas (1) and (2), X and Z represent divalent organic groups independently of each other, Y represents a tetravalent organic group, and * represents a bond.]
    Including the structural unit represented by, as Y in the formula (1), the formula (3):
    Figure JPOXMLDOC01-appb-C000002
     [In the formula (3), R 1 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group which may have a halogen atom or a halogen atom independently of each other, and R 2 to R 5 are Independently of each other, they represent a monovalent hydrocarbon group which may have a hydrogen atom or a halogen atom, m represents an integer of 0 to 3 independently of each other, and n represents an integer of 1 to 4. * represents a bonding hand, provided that at least one benzene ring having R 2 ~ R 5, at least one 1 may have a halogen atom monovalent hydrocarbon group R 2 ~ R 5]
    Polyamide-imide resin containing the structure represented by.
  2. 　式（１）及び式（２）中のＸとして、２価の芳香族基、２価の脂環族基、及び２価の脂肪族基の少なくとも１種を含む、請求項１に記載のポリアミドイミド樹脂。 The polyamide according to claim 1, wherein X in the formulas (1) and (2) contains at least one of a divalent aromatic group, a divalent alicyclic group, and a divalent aliphatic group. Iimide resin.
  3. 　式（１）及び式（２）中のＸとして、式（４）：
    Figure JPOXMLDOC01-appb-C000003
     ［式（４）中、Ａは、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＡ１）－又は－Ｓｉ（ＲＡ２）２－を表し、ＲＡ１及びＲＡ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表し、Ｒ６は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、ｓは、互いに独立に、０～４の整数を表し、＊は結合手を表す］
    で表される構造を含む、請求項１又は２に記載のポリアミドイミド樹脂。     As X in the formula (1) and the formula (2), the formula (4):
    Figure JPOXMLDOC01-appb-C000003
     [In formula (4), A is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-,-. PO -, - PO 2 -, - N (R A1) - , or -Si (R A2) 2 - represents, R A1 and R A2 are, independently of one another, may have a hydrogen atom, or a halogen atom Representing an alkyl group, R 6 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, which may have a halogen atom or a halogen atom independently of each other, and s represents 0 to independently of each other. Represents an integer of 4, * represents a bond]
    The polyamide-imide resin according to claim 1 or 2, which comprises the structure represented by.
  4. 　式（１）中のＹとして、式（５）：
    Figure JPOXMLDOC01-appb-C000004
     ［式（５）中、Ｂは、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＣＯＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＢ１）－又は－Ｓｉ（ＲＢ２）２－を表し、ＲＢ１及びＲＢ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表し、Ｒ７は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、ｔは、互いに独立に、０～３の整数を表し、＊は結合手を表す］
    で表される構造をさらに含む、請求項１～３のいずれかに記載のポリアミドイミド樹脂。     As Y in equation (1), equation (5):
    Figure JPOXMLDOC01-appb-C000004
     [In formula (5), B is a single bond, -O-, a diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2- , -S-, -CO-,-. It represents COO-, -PO-, -PO 2- , -N ( RB1 )-or-Si ( RB2 ) 2- , and RB1 and RB2 have hydrogen atoms or halogen atoms independently of each other. Represents an alkyl group which may have an alkyl group, R 7 represents an alkyl group, an alkoxy group, an aryl group, or an aryloxy group which may have a halogen atom and a halogen atom independently of each other, and t represents an alkyl group which may have a halogen atom and a halogen atom. Represents an integer from 0 to 3, and * represents a bond]
    The polyamide-imide resin according to any one of claims 1 to 3, further comprising a structure represented by.
  5. 　式（２）中のＺとして、式（６）：
    Figure JPOXMLDOC01-appb-C000005
     ［式（６）中、Ｗは、互いに独立に、単結合、－Ｏ－、ジフェニルメチレン基、ハロゲン原子を有してもよい２価の炭化水素基、－ＳＯ２－、－Ｓ－、－ＣＯ－、－ＰＯ－、－ＰＯ２－、－Ｎ（ＲＣ１）－又は－Ｓｉ（ＲＣ２）２－を表し、ＲＣ１及びＲＣ２は、互いに独立に、水素原子、又はハロゲン原子を有してもよいアルキル基を表し、Ｒ８は、互いに独立に、ハロゲン原子、ハロゲン原子を有してもよい、アルキル基、アルコキシ基、アリール基、又はアリールオキシ基を表し、ｐは、互いに独立に、０～４の整数を表し、ｑは０～４の整数を表し、＊は結合手を表す］
    で表される構造を含む、請求項１～４のいずれかに記載のポリアミドイミド樹脂。     As Z in equation (2), equation (6):
    Figure JPOXMLDOC01-appb-C000005
     Wherein (6), W, independently of one another, a single bond, -O-, diphenylmethylene group, a divalent hydrocarbon group which may have a halogen atom, -SO 2 -, - S - , - It represents CO-, -PO-, -PO 2- , -N ( RC1 )-or-Si ( RC2 ) 2- , and RC1 and RC2 have hydrogen atom or halogen atom independently of each other. R 8 represents an alkyl group which may have a halogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, or an aryloxy group, and p is independent of each other. , 0 to 4 represents an integer, q represents an integer from 0 to 4, and * represents a bond.]
    The polyamide-imide resin according to any one of claims 1 to 4, which comprises the structure represented by.
  6. 　重量平均分子量は１００，０００以上である、請求項１～５のいずれかに記載のポリアミドイミド樹脂。 The polyamide-imide resin according to any one of claims 1 to 5, which has a weight average molecular weight of 100,000 or more.
  7. 　請求項１～６のいずれかに記載のポリアミドイミド樹脂を含む、光学フィルム。 An optical film containing the polyamide-imide resin according to any one of claims 1 to 6.
  8. 　黄色度は３．０未満である、請求項７に記載の光学フィルム。 The optical film according to claim 7, wherein the yellowness is less than 3.0.
  9. 　全光線透過率は９０％以上である、請求項７又は８に記載の光学フィルム。 The optical film according to claim 7 or 8, wherein the total light transmittance is 90% or more.
  10. 　弾性率は５．０ＧＰａ以上である、請求項７～９のいずれかに記載の光学フィルム。 The optical film according to any one of claims 7 to 9, which has an elastic modulus of 5.0 GPa or more.
  11. 　フレキシブル表示装置の前面板用フィルムである、請求項７～１０のいずれかに記載の光学フィルム。 The optical film according to any one of claims 7 to 10, which is a film for the front plate of a flexible display device.
  12. 　請求項７～１１のいずれかに記載の光学フィルムを備える、フレキシブル表示装置。 A flexible display device including the optical film according to any one of claims 7 to 11.
  13. 　タッチセンサをさらに備える、請求項１２に記載のフレキシブル表示装置。 The flexible display device according to claim 12, further comprising a touch sensor.
  14. 　偏光板をさらに備える、請求項１２又は１３に記載のフレキシブル表示装置。 The flexible display device according to claim 12 or 13, further comprising a polarizing plate.
PCT/JP2020/039650 2019-10-31 2020-10-22 Polyamideimide resin WO2021085283A1 (en)

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Citations (5)

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JP2010174195A (en) * 2009-01-30 2010-08-12 Asahi Kasei Corp Polyimide polyamide copolymer and photosensitive resin composition
JP2013127049A (en) * 2011-11-15 2013-06-27 Jsr Corp Method for producing film-forming material, film and liquid crystal display element
WO2016152459A1 (en) * 2015-03-24 2016-09-29 コニカミノルタ株式会社 Polyimide-based optical film, process for producing same, and organic electroluminescent display
KR20180090671A (en) * 2017-02-03 2018-08-13 주식회사 엘지화학 Polyamideimide copolymers and polyamideimide film comprising the same
WO2020138360A1 (en) * 2018-12-28 2020-07-02 三菱瓦斯化学株式会社 Imide-(amic acid) copolymer and method for producing same, varnish, and polyimide film

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010174195A (en) * 2009-01-30 2010-08-12 Asahi Kasei Corp Polyimide polyamide copolymer and photosensitive resin composition
JP2013127049A (en) * 2011-11-15 2013-06-27 Jsr Corp Method for producing film-forming material, film and liquid crystal display element
WO2016152459A1 (en) * 2015-03-24 2016-09-29 コニカミノルタ株式会社 Polyimide-based optical film, process for producing same, and organic electroluminescent display
KR20180090671A (en) * 2017-02-03 2018-08-13 주식회사 엘지화학 Polyamideimide copolymers and polyamideimide film comprising the same
WO2020138360A1 (en) * 2018-12-28 2020-07-02 三菱瓦斯化学株式会社 Imide-(amic acid) copolymer and method for producing same, varnish, and polyimide film

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