WO2013035810A1 - Liquid crystal display element - Google Patents

Liquid crystal display element Download PDF

Info

Publication number
WO2013035810A1
WO2013035810A1 PCT/JP2012/072804 JP2012072804W WO2013035810A1 WO 2013035810 A1 WO2013035810 A1 WO 2013035810A1 JP 2012072804 W JP2012072804 W JP 2012072804W WO 2013035810 A1 WO2013035810 A1 WO 2013035810A1
Authority
WO
WIPO (PCT)
Prior art keywords
liquid crystal
alignment film
chiral compound
chiral
crystal composition
Prior art date
Application number
PCT/JP2012/072804
Other languages
French (fr)
Japanese (ja)
Inventor
直子 沖本
岡部　将人
石川　誠
Original Assignee
大日本印刷株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 大日本印刷株式会社 filed Critical 大日本印刷株式会社
Publication of WO2013035810A1 publication Critical patent/WO2013035810A1/en

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K19/00—Liquid crystal materials
    • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
    • C09K19/06—Non-steroidal liquid crystal compounds
    • C09K19/08—Non-steroidal liquid crystal compounds containing at least two non-condensed rings
    • C09K19/30—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing saturated or unsaturated non-aromatic rings, e.g. cyclohexane rings
    • C09K19/3001—Cyclohexane rings
    • C09K19/3003—Compounds containing at least two rings in which the different rings are directly linked (covalent bond)
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K19/00—Liquid crystal materials
    • C09K19/02—Liquid crystal materials characterised by optical, electrical or physical properties of the components, in general
    • C09K19/0225—Ferroelectric
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K19/00—Liquid crystal materials
    • C09K19/04—Liquid crystal materials characterised by the chemical structure of the liquid crystal components, e.g. by a specific unit
    • C09K19/06—Non-steroidal liquid crystal compounds
    • C09K19/08—Non-steroidal liquid crystal compounds containing at least two non-condensed rings
    • C09K19/30—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing saturated or unsaturated non-aromatic rings, e.g. cyclohexane rings
    • C09K19/3001—Cyclohexane rings
    • C09K19/3003—Compounds containing at least two rings in which the different rings are directly linked (covalent bond)
    • C09K2019/3025—Cy-Ph-Ph-Ph
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/137—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering
    • G02F1/139—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent
    • G02F1/141—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent using ferroelectric liquid crystals

Definitions

  • the present invention relates to a liquid crystal display element using a ferroelectric liquid crystal composition.
  • Liquid crystal display elements are widely used from large displays to portable information terminals because of their thinness and low power consumption, and their development is actively underway. So far, liquid crystal display elements have been developed and put to practical use, such as TN mode, STN multiplex drive, and active matrix drive using thin layer transistors (TFTs) for TN, but these use nematic liquid crystals. In addition, the response speed of the liquid crystal material is as slow as several ms to several tens of ms, and it cannot be said that it is sufficiently compatible with moving image display.
  • TFTs thin layer transistors
  • Ferroelectric liquid crystal is expected to provide a high-performance liquid crystal display element because it has a superior response speed such as a wide viewing angle because it has a response speed as short as ⁇ s and is suitable for high-speed devices. .
  • the ferroelectric liquid crystal has a higher molecular order than the nematic liquid crystal, so that it is difficult to return to its original state when the regularity of molecular orientation is disturbed by impact, that is, it is very weak to external impact.
  • a method of arranging a partition wall (also referred to as a rib) between a pair of substrates has been proposed (see, for example, Patent Document 1 and Patent Document 2).
  • a partition wall also referred to as a rib
  • a method of adding a gelling agent to a ferroelectric liquid crystal composition for example, a method of adding a curable resin to a ferroelectric liquid crystal composition, A method of adding a thermoplastic resin to a dielectric liquid crystal composition (see Patent Document 4), a method using a ferroelectric polymer liquid crystal having a ferroelectric liquid crystal structure in the side chain, a liquid crystal polymer compound and a low molecular ferroelectric A method of mixing a conductive liquid crystal compound (see Patent Document 5) has been proposed. However, these methods have a problem that the drive voltage becomes high.
  • the regularity of the molecular orientation is less likely to be disturbed to a certain degree of weak impact, but the orientation regularity is disturbed by a strong impact.
  • the essential problem that it is difficult to return to the original state has not been solved.
  • Patent Document 6 when a ferroelectric liquid crystal composition containing a chiral compound having a predetermined structure in which four benzene rings are directly bonded is used, the contrast ratio is good even after an impact is applied. It has been reported that
  • a pair of rubbing alignment films is generally arranged so that the rubbing treatment directions are parallel.
  • the alignment films subjected to the rubbing treatment are arranged so that the rubbing treatment directions are parallel and the same direction (also referred to as parallel), and the rubbing treatment directions are parallel and opposite directions (also referred to as anti-parallel). It may be arranged to be. Conventionally, it has been preferable to be arranged in an antiparallel manner (see, for example, Patent Document 7). This is because the liquid crystal molecules 101 are given a pretilt by the alignment films 100a and 100b subjected to the rubbing process as illustrated in FIGS.
  • JP 2004-77541 A International Publication No. 02/03131 Pamphlet JP 2004-233414 A JP 2003-114440 A Japanese Patent No. 3541437 International Publication No. 2010/031431 Pamphlet JP 2006-220675 A
  • the present inventors produced a liquid crystal display element in which rubbing-treated alignment films were arranged in antiparallel using a ferroelectric liquid crystal composition capable of exhibiting impact resistance.
  • a ferroelectric liquid crystal composition capable of exhibiting impact resistance.
  • the present invention includes a first base material, a first electrode layer formed on the first base material, and a first alignment film formed on the first electrode layer and rubbed.
  • a second alignment having an alignment substrate, a second substrate, a second electrode layer formed on the second substrate, and a second alignment film formed on the second electrode layer and rubbed.
  • a liquid crystal display element having a processing substrate and a liquid crystal layer formed between the first alignment film and the second alignment film and containing a ferroelectric liquid crystal composition, wherein the first alignment film and the second alignment film
  • the alignment film is arranged so that the rubbing treatment direction is parallel, and the ferroelectric liquid crystal composition is represented by the chiral compound A represented by the following general formula (1) and the following general formula (2). Containing at least one chiral compound of chiral compound B To provide a liquid crystal display element according to symptoms.
  • R 1 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
  • R 2 is a chiral group and is a group represented by the following general formula (3).
  • R 3 is a saturated or unsaturated alkyl or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
  • Y 1 represents —CH 3 or a fluorine atom.
  • m is 0 or 1.
  • n is 0 or 1. * Indicates a chiral center.
  • X 1 to X 8 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 1 to X 8 are each independently —CH 3 , —CF 3 or a halogen atom.
  • R 4 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
  • R 5 is a chiral group, and is a group represented by the above formula (3).
  • X 9 to X 20 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 9 to X 20 are each independently —CH 3 , —CF 3 or a halogen atom.
  • K represents a single bond or a cyclohexane ring.
  • the compound contains at least one chiral compound of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2), and is capable of exhibiting impact resistance.
  • the first alignment film and the second alignment film are arranged so that the rubbing treatment directions are parallel, thereby enabling a liquid crystal display element having excellent display quality. Become.
  • the constituent material of the first alignment film and the constituent material of the second alignment film preferably have different compositions. This is because the occurrence of alignment defects can be suppressed and the contrast can be improved.
  • a ferroelectric compound containing at least one of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2) and exhibiting impact resistance When the first liquid crystal composition is used, the first alignment film and the second alignment film are arranged so that the rubbing treatment directions are parallel, whereby the liquid crystal display element having excellent display quality can be obtained. Play.
  • the liquid crystal display element of the present invention has a first base material, a first electrode layer formed on the first base material, and a first alignment film formed on the first electrode layer and subjected to a rubbing process.
  • a first alignment treatment substrate, a second substrate, a second electrode layer formed on the second substrate, and a second alignment film formed on the second electrode layer and subjected to a rubbing treatment A liquid crystal display element having a two-alignment-treated substrate and a liquid crystal layer formed between the first alignment film and the second alignment film and containing a ferroelectric liquid crystal composition, wherein the first alignment film and the above-mentioned
  • the second alignment film is arranged so that the rubbing treatment direction is parallel, and the ferroelectric liquid crystal composition is represented by the chiral compound A represented by the above formula (1) and the above formula (2). Containing at least one chiral compound of chiral compound B, Is shall.
  • FIG. 1 is a schematic cross-sectional view showing an example of the liquid crystal display element of the present invention.
  • the liquid crystal display element 1 includes a first alignment treatment substrate 11a in which a first electrode layer 3a and a first alignment film 4a are formed on a first substrate 2a, and a second substrate 2b.
  • a liquid crystal containing a ferroelectric liquid crystal composition is formed between the second alignment substrate 11b on which the second electrode layer 3b and the second alignment film 4b are formed, and the first alignment film 4a and the second alignment film 4b.
  • Layer 5 is a schematic cross-sectional view showing an example of the liquid crystal display element of the present invention.
  • the liquid crystal display element 1 includes a first alignment treatment substrate 11a in which a first electrode layer 3a and a first alignment film 4a are formed on a first substrate 2a, and a second substrate 2b.
  • a liquid crystal containing a ferroelectric liquid crystal composition is formed between the second alignment substrate 11b on which the second electrode layer 3b and the second alignment film 4b are
  • the first alignment film 4a and the second alignment film 4b are both rubbed films and are arranged so that the rubbing directions D1 and D2 are parallel.
  • the ferroelectric liquid crystal composition contained in the liquid crystal layer 5 contains at least one chiral compound of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2). Yes.
  • a ferroelectric liquid crystal composition exhibiting bistability in which a phase series reaches a Kaille smectic C phase via a smectic A phase is known.
  • the ferroelectric liquid crystal composition exhibiting such bistability has one smectic layer structure and two stable states 25a and 25b with respect to the layer normal z. ing.
  • two kinds of stable states 25a and 25b can be achieved by applying a positive or negative polarity voltage to align the direction of spontaneous polarization of the liquid crystal molecules 25.
  • ferroelectric liquid crystal composition a ferroelectric liquid crystal composition exhibiting monostability in which the phase series reaches the chiral smectic C phase without passing through the smectic A phase and has a half V-shaped switching characteristic. It has been known.
  • the layer normal z is inclined with respect to the rubbing treatment direction d as illustrated in FIG. It is formed in the direction.
  • FIG. 5 two domains having different layer normal z directions are generated. In the two domains, the liquid crystal molecules 25 operate only with positive and negative voltages of opposite polarities. I can not use it.
  • the ferroelectric liquid crystal composition in the present invention contains at least one of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2).
  • the ferroelectric liquid crystal composition in the present invention also exhibits monostability.
  • the present inventors have used such a ferroelectric liquid crystal composition, and in various rubbing alignment film combinations and rubbing treatment methods, stable positions of liquid crystal molecules when no voltage is applied, and liquid crystal molecules when a voltage is applied As a result of analyzing the behavior of the following, we found the following.
  • FIGS. 6 (a) and 6 (b) An example of a plan view of a liquid crystal display element using the ferroelectric liquid crystal composition of the present invention is shown in FIGS. 6 (a) and 6 (b).
  • FIGS. 6A and 6B there are two types of directions in which the liquid crystal molecules 25 are stabilized with respect to the rubbing treatment direction d when no voltage is applied.
  • the liquid crystal molecules 25 move to the left when a negative polarity voltage is applied, and the liquid crystal molecules 25 move to the right when a positive polarity voltage is applied. Further, the operating angle of the liquid crystal molecules 25 when a negative polarity voltage is applied is larger.
  • FIG. 6B compared with the case of FIG.
  • the operation directions of the liquid crystal molecules 25 with respect to the positive and negative polarities are the same, but the operation angle is opposite and the negative polarity is obtained. Is small when a positive voltage is applied, and is large when a positive polarity voltage is applied. In either case, the positions when positive and negative voltages are applied coincide with each other.
  • the operation of such liquid crystal molecules is different from the conventional ferroelectric liquid crystal composition that exhibits monostability and has half V-shaped switching characteristics as described above.
  • FIGS. 7A and 7B show a cross-sectional view of a liquid crystal display element using the ferroelectric liquid crystal composition in the present invention.
  • each of the upper and lower rubbing alignment films in contact with the liquid crystal layer is strongly influenced as shown in (i) and (iii).
  • the pretilt angles of the liquid crystal molecules 25 are different in the domain, as shown in (ii) and (iv)
  • the stable positions of the liquid crystal molecules 25 when no voltage is applied in plan view are substantially the same. Therefore, by reducing the pretilt angle of the liquid crystal molecules by the rubbing alignment film, the difference between the two domains is reduced, so that the monodomain can be easily aligned.
  • the present invention contains at least one of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2) and exhibits impact resistance.
  • the ferroelectric liquid crystal composition to be obtained is used, the first alignment film and the second alignment film are arranged so that the rubbing treatment directions are parallel, so that liquid crystal molecules when no voltage is applied in plan view
  • These liquid crystal display elements can be provided with excellent display quality.
  • A. 1st alignment film and 2nd alignment film are films
  • the first alignment film and the second alignment film are arranged so that the rubbing treatment directions are parallel, that the rubbing treatment direction of the first alignment film and the rubbing treatment direction of the second alignment film are parallel and The same direction. That the rubbing treatment direction of the first alignment film and the rubbing treatment direction of the second alignment film are parallel means that the angle formed by the rubbing treatment direction of the first alignment film and the rubbing treatment direction of the second alignment film is 0 ⁇ 5. It is within the range of degrees.
  • the first alignment film and the second alignment film are arranged so that the rubbing treatment directions are parallel. be able to.
  • the direction in which the rubbing process is performed can be determined from the pretilt direction of the liquid crystal molecules.
  • the pretilt angle can be measured by a crystal rotation method.
  • the pretilt angle of the liquid crystal molecules with respect to the first alignment film and the second alignment film is not particularly limited, but is preferably 10 degrees or less, more preferably 5 from the viewpoint of display quality and impact resistance. Degrees or less, more preferably 3 degrees or less.
  • the pretilt angle of the liquid crystal molecules with respect to the first alignment film and the second alignment film is preferably 10 degrees or less, more preferably 5 from the viewpoint of display quality and impact resistance. Degrees or less, more preferably 3 degrees or less.
  • the pretilt angle is preferably as small as possible, the lower limit of the pretilt angle is not particularly limited, but is usually about 1 degree.
  • the pretilt angle can be appropriately adjusted depending on the materials of the first alignment film and the second alignment film, the conditions of the rubbing treatment, and the like.
  • the material used for the first alignment film and the second alignment film is not particularly limited as long as anisotropy can be imparted to the film by rubbing treatment.
  • nylon, polyimide, polyamide examples thereof include polyamic acid, polyamideimide, polyetherimide, polyvinyl alcohol, and polyurethane. These may be used alone or in combination of two or more.
  • the first alignment film and the second alignment film contain polyimide. This is because the liquid crystal molecules are easily aligned in the azimuth direction in the first alignment film and the second alignment film containing polyimide. That is, the liquid crystal molecules are easily arranged in a certain direction.
  • the polyimide used for the first alignment film and the second alignment film preferably has a pretilt angle in the above range.
  • a pretilt angle in the above range.
  • a method of controlling the pretilt angle by changing the chain length of the polymer side chain is known, and it has been reported that the pretilt angle increases as the side chain length increases.
  • the pretilt angle can be controlled by adjusting the amount of roller pressing, the number of rotations, the speed, the number of rubbing processes, and the like in the rubbing process. In order to set the pretilt angle within the above range, for example, it is preferable to reduce the push-in amount.
  • the thickness of the first alignment film and the second alignment film is set to about 1 nm to 1000 nm, and preferably in the range of 50 nm to 100 nm.
  • the constituent material of the first alignment film and the constituent material of the second alignment film preferably have different compositions across the liquid crystal layer. This is because by adopting such a configuration, the direction of spontaneous polarization of liquid crystal molecules can be made uniform, and a monodomain can be formed. Moreover, it is because generation
  • the ferroelectric liquid crystal composition and the first alignment are used in the first alignment film and the second alignment film. It is considered that the polar surface interaction, which is the interaction between the film surface and the second alignment film surface, is different. Therefore, in the first alignment film and the second alignment film, when the second alignment film tends to have a relatively positive polarity, as illustrated in FIG. It is considered that the positive polarity of the spontaneous polarization Ps of the liquid crystal molecules 25 faces the first alignment film 4a side due to the polar surface interaction. On the other hand, in the first alignment film and the second alignment film, when the first alignment film tends to have a relatively positive polarity, as illustrated in FIG.
  • the positive polarity of the spontaneous polarization Ps of the liquid crystal molecules 25 faces the second alignment film 4b side due to the polar surface interaction.
  • the direction of spontaneous polarization is such a direction because the direction of spontaneous polarization is the direction in which the polarization of the liquid crystal molecules and the alignment film are electrically balanced, and the liquid crystal molecules are in an electrically stable state. It seems to be because. 8 and 9, the liquid crystal layer shows liquid crystal molecules.
  • the polarities of the first alignment film surface and the second alignment film surface can be made different depending on the respective materials. it can.
  • the polar surface interaction between the ferroelectric liquid crystal composition and the first alignment film is different from the polar surface interaction between the ferroelectric liquid crystal composition and the second alignment film.
  • the direction of spontaneous polarization can be controlled by appropriately selecting a material in consideration of the surface polarity of the second alignment film. As a result, the occurrence of alignment defects peculiar to the ferroelectric liquid crystal composition can be suppressed, and the contrast can be improved. Furthermore, a monodomain orientation can be obtained.
  • composition of the constituent materials of the first alignment film and the second alignment film different, for example, a method of different types of material systems such as using polyimide on one side and nylon on the other side, polyimides having different side chains And the like, a method of varying the side chain, a method of changing the content of the additive, and a method of varying the content of each component such as the presence or absence of the additive.
  • the liquid crystal layer in the present invention is formed between the first alignment film of the first alignment treatment substrate and the second alignment film of the second alignment treatment substrate, and includes a ferroelectric liquid crystal composition.
  • a ferroelectric liquid crystal composition Asinafter, each configuration in the liquid crystal layer will be described.
  • Ferroelectric liquid crystal composition used in the present invention is a chiral compound of at least one of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2). It contains a compound.
  • each component in the ferroelectric liquid crystal composition will be described.
  • Chiral compound The chiral compound used in the present invention is at least one of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2).
  • the ferroelectric liquid crystal composition only needs to contain at least one of the chiral compound A and the chiral compound B.
  • the ferroelectric liquid crystal composition may contain only the chiral compound A or only the chiral compound B. It may contain, and the chiral compound A and the chiral compound B may be contained.
  • the ferroelectric liquid crystal composition may contain one kind of chiral compound A or two or more kinds of chiral compounds A.
  • the ferroelectric liquid crystal composition contains the chiral compound B, it may contain one kind of chiral compound B or may contain two or more kinds of chiral compounds B.
  • R 1 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
  • R 2 is a chiral group and is a group represented by the following general formula (3).
  • R 3 is a saturated or unsaturated alkyl or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
  • Y 1 represents —CH 3 or a fluorine atom.
  • m is 0 or 1.
  • n is 0 or 1. * Indicates a chiral center.
  • X 1 to X 8 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 1 to X 8 are each independently —CH 3 , —CF 3 or a halogen atom.
  • R 1 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
  • the number of carbon atoms may be 4 to 18, but 6 to 18 is preferable and 6 to 12 is more preferable. This is because when the number of carbon atoms is larger than the above range, the synthesis of the chiral compound A becomes difficult and the cost increases. On the other hand, if the number of carbon atoms is less than the above range, the ferroelectric liquid crystal composition may not exhibit a smectic phase.
  • the ferroelectric liquid crystal composition may exhibit a smectic phase with a relatively small number of carbon atoms.
  • the alkyl group or alkoxyalkyl group may be substituted with a halogen atom or may not be substituted with a halogen atom, but is preferably not substituted with a halogen atom.
  • the alkyl group or alkoxyalkyl group is linear or branched.
  • the alkyl group or alkoxyalkyl group may be saturated or unsaturated, but is preferably saturated.
  • R 1 may be an alkyl group or an alkoxyalkyl group, but is preferably an alkyl group.
  • R 2 is a chiral group having one or more chiral centers, and is a group represented by the above formula (3).
  • R 3 is a saturated or unsaturated alkyl group or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
  • the alkyl group or alkoxyalkyl group is linear, branched or cyclic.
  • R 3 may be an alkyl group or an alkoxyalkyl group, but is preferably an alkyl group.
  • Y 1 represents —CH 3 or a fluorine atom.
  • —CH 3 there is an advantage that the synthesis of the chiral compound A is easy.
  • fluorine atoms there is an advantage that the magnitude of the spontaneous polarization of the liquid crystal molecules can be increased and the response speed can be increased.
  • Y 1 may be —CH 3 or a fluorine atom, and among them, —CH 3 is preferable.
  • the synthesis of the chiral compound A is easy, the chiral compound A can be produced stably, and the ferroelectric liquid crystal composition can be obtained at a low cost.
  • m is 0 or 1.
  • * indicates a chiral center.
  • n 0 or 1.
  • X 1 to X 8 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 1 to X 8 are each independently —CH 3 , —CF 3 or a halogen atom.
  • X 1 to X 8 are hydrogen atoms, solubility of the chiral compound A decreases, so that the synthesis and purification of the chiral compound A becomes difficult, the cost increases, and the ferroelectric liquid crystal The composition is easily crystallized, and the desired impact resistance may not be obtained.
  • any one or more of X 1 to X 3 and X 5 to X 7 are preferably each independently —CH 3 , —CF 3 or a halogen atom. This is because the chiral compound has better solubility than the X 4 and X 8 positions when it has a substituent at the X 1 to X 3 and X 5 to X 7 positions. This is presumably because the X 4 and X 8 positions are less distorted by substituents than the other positions.
  • the benzene ring having a substituent can have 1 to 4 substituents, and among them, it can have one substituent. preferable. That is, when the benzene ring to which X 1 , X 2 , X 5 , and X 6 are bonded has a substituent, any one of X 1 , X 2 , X 5 , and X 6 is —CH 3 , —CF 3 or a halogen atom is preferable.
  • any one of X 3 , X 4 , X 7 , X 8 is —CH 3 , It is preferably —CF 3 or a halogen atom. In particular, it is preferable that only one of X 1 to X 8 is —CH 3 , —CF 3 or a halogen atom.
  • the benzene ring which has a substituent has two substituents.
  • fluorine atoms are respectively substituted on adjacent carbon atoms of the benzene ring as in the case where, for example, X 1 and X 2 are fluorine atoms.
  • the rod-like structure of the chiral compound is not destroyed, so that the impact resistance can be maintained.
  • one benzene ring preferably has two substituents, and among them, X 1 , X 2 , X 5 , X 6
  • the benzene ring to which is bonded preferably has two substituents. This is because, among the three directly bonded benzene rings, the ferroelectric liquid crystal composition is difficult to crystallize because the middle benzene ring has a substituent.
  • X 1 and X 2 or X 5 and X 6 are preferably fluorine atoms.
  • the substituent that the benzene ring has is preferably —CH 3 , a fluorine atom, or a chlorine atom, and particularly preferably —CH 3 or a fluorine atom, when there is one substituent.
  • any substituent is a fluorine atom.
  • the two fluorine atoms are preferably substituted with adjacent carbon atoms.
  • chiral compound A represented by the above formula (1) examples include chiral compounds represented by the following general formulas (1-1) to (1-2) and (1-3) to (1-4) A is mentioned.
  • R 11 is a saturated or unsaturated alkyl group having 1 to 10 carbon atoms. Represents a chiral center, m is 0 or 1, p is 4 to 18, X 21 and X 22 each independently represent —CH 3 , —CF 3 or a halogen atom, and the above formula (1-1 ) To (1-2), one of j and k is 0 and the other is 1.)
  • p is 4 to 18, preferably 6 to 18, and more preferably 6 to 12.
  • the number of carbon atoms is larger than the above range, the synthesis of the chiral compound A becomes difficult.
  • the ferroelectric liquid crystal composition may not exhibit a smectic phase.
  • R 11 is a saturated or unsaturated alkyl group having 1 to 10 carbon atoms.
  • the alkyl group is linear, branched or cyclic.
  • R 11 is preferably a linear or branched saturated alkyl group or a phenylalkyl group.
  • m is 0 or 1.
  • * indicates a chiral center.
  • the carbon atom at the 1-position is a chiral center.
  • the 1-position carbon atom becomes a chiral center
  • m 1, the 2-position carbon atom becomes a chiral center.
  • X 21 and X 22 each independently represent —CH 3 , —CF 3 or a halogen atom. Among them, —CH 3 , a fluorine atom or a chlorine atom is preferable, and —CH 3 or a fluorine atom is particularly preferable.
  • the positions of X 21 and X 22 are the same as the positions of X 1 to X 8 described above.
  • chiral compound A represented by the above formulas (1-1) and (1-2) include a chiral compound A represented by the following formula.
  • chiral compound A represented by the above formulas (1-3) and (1-4) include a chiral compound A represented by the following formula.
  • the dextrorotatory property is indicated by (+) and the levorotatory property is indicated by ( ⁇ ).
  • chiral compound A one kind may be used alone, or two or more kinds may be mixed and used.
  • the content of the chiral compound A in the ferroelectric liquid crystal composition is not particularly limited as long as an impact resistance effect is obtained.
  • the content of the chiral compound A is ferroelectric.
  • each content of two or more of the chiral compounds A is ferroelectric. It is preferable that it is 5 mass% or more in a crystalline liquid crystal composition.
  • Chiral compound A can be synthesized, for example, by the method described in International Publication No. 2010/031431.
  • R 4 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
  • R 5 is a chiral group and is a group represented by the following formula (3).
  • R 3 is a saturated or unsaturated alkyl or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
  • Y 1 represents —CH 3 or a fluorine atom.
  • m is 0 or 1.
  • n is 0 or 1. * Indicates a chiral center.
  • X 9 to X 20 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 9 to X 20 are each independently —CH 3 , —CF 3 or a halogen atom.
  • K represents a single bond or a cyclohexane ring.
  • K represents a single bond or a cyclohexane ring.
  • the chiral compound B is a compound in which four benzene rings are directly bonded.
  • the chiral compound B is obtained by directly bonding four benzene rings and one cyclohexane ring, as represented by the following general formula (2-2).
  • K is preferably a single bond.
  • R 4 is a non-chiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
  • the number of carbon atoms may be 4 to 18, but 6 to 18 is preferable and 6 to 12 is more preferable. This is because when the number of carbon atoms is larger than the above range, the synthesis of the chiral compound B becomes difficult and the cost increases. On the other hand, if the number of carbon atoms is less than the above range, the ferroelectric liquid crystal composition may not exhibit a smectic phase.
  • the ferroelectric liquid crystal composition may exhibit a smectic phase with a relatively small number of carbon atoms.
  • the alkyl group or alkoxyalkyl group may be substituted with a halogen atom or may not be substituted with a halogen atom, but is preferably not substituted with a halogen atom.
  • the alkyl group or alkoxyalkyl group is linear or branched.
  • the alkyl group or alkoxyalkyl group may be saturated or unsaturated, but is preferably saturated.
  • R 4 may be an alkyl group or an alkoxyalkyl group, but is preferably an alkyl group.
  • R 5 is a chiral group having one or more chiral centers, and is a group represented by the above formula (3).
  • R 3 is a saturated or unsaturated alkyl group or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
  • the alkyl group or alkoxyalkyl group is linear, branched or cyclic.
  • R 3 may be an alkyl group or an alkoxyalkyl group, but is preferably an alkyl group.
  • Y 1 represents —CH 3 or a fluorine atom.
  • —CH 3 there is an advantage that the synthesis of the chiral compound B is easy.
  • fluorine atoms there is an advantage that the magnitude of the spontaneous polarization of the liquid crystal molecules can be increased and the response speed can be increased.
  • Y 1 may be —CH 3 or a fluorine atom, and among them, —CH 3 is preferable. This is because the chiral compound B can be easily synthesized as described above, the chiral compound B can be stably produced, and a ferroelectric liquid crystal composition can be obtained at a low cost.
  • m is 0 or 1.
  • * indicates a chiral center.
  • n 0 or 1.
  • X 9 to X 20 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 9 to X 20 are each independently —CH 3 , —CF 3 or a halogen atom.
  • X 9 to X 20 are hydrogen atoms, solubility of the chiral compound B decreases, so that the synthesis and purification of the chiral compound B becomes difficult, the cost increases, and the ferroelectric liquid crystal The composition is easily crystallized, and the desired impact resistance may not be obtained.
  • any one or more of X 9 to X 13 and X 15 to X 19 are preferably each independently —CH 3 , —CF 3 or a halogen atom. This is because the chiral compound has better solubility than the X 14 and X 20 positions when it has a substituent at the X 9 to X 13 and X 15 to X 19 positions. This is presumably because the X 14 and X 20 positions are less distorted by substituents than the other positions.
  • the benzene ring having a substituent can have 1 to 4 substituents, and among them, it can have one substituent. preferable. That is, when the benzene ring to which X 9 , X 10 , X 15 , and X 16 are bonded has a substituent, any one of X 9 , X 10 , X 15 , and X 16 is —CH 3 , —CF 3 or a halogen atom is preferable.
  • any one of X 11 , X 12 , X 17 , and X 18 is —CH 3 , — CF 3 or a halogen atom is preferred.
  • any one of X 13 , X 14 , X 19 and X 20 is —CH 3 , — CF 3 or a halogen atom is preferred.
  • one or two benzene rings each have one substituent among the three benzene rings to which X 9 to X 20 are bonded. That is, the total number of substituents of the three benzene rings to which X 9 to X 20 are bonded is preferably 1 or 2.
  • the benzene ring which has a substituent has two substituents.
  • the position of the two substituents is such that, for example, when X 9 and X 10 are fluorine atoms, the adjacent carbon atoms of the benzene ring are each substituted with a fluorine atom. It is preferable. Further, it is preferable that one of the three benzene rings to which X 9 to X 20 are bonded has one substituent.
  • the total number of substituents of the three benzene rings to which X 9 to X 20 are bonded is two, and that one benzene ring has two substituents.
  • the benzene ring to which X 9 , X 10 , X 15 , X 16 or X 11 , X 12 , X 17 , X 18 is bonded has two substituents. This is because, among the four directly bonded benzene rings, the ferroelectric liquid crystal composition is difficult to crystallize because the middle benzene ring has a substituent.
  • X 9 and X 10 , X 11 and X 12 , X 15 and X 16 , or X 17 and X 18 are preferably fluorine atoms.
  • the substituent that the benzene ring has is preferably —CH 3 , a fluorine atom, or a chlorine atom, and particularly preferably —CH 3 or a fluorine atom, when there is one substituent.
  • any substituent is a fluorine atom.
  • the two fluorine atoms are preferably substituted with adjacent carbon atoms.
  • the total number of substituents on the three benzene rings to which X 9 to X 20 are bonded is preferably 3 to 8. This is because when the total number of substituents is large, crystallization of the ferroelectric liquid crystal composition can be suppressed.
  • the total number of substituents is preferably 3 to 5, more preferably 3.
  • Benzene ring having two substituents benzene ring to which X 9 , X 10 , X 15 , and X 16 are bonded, and X 13 , X 14 , X 19 , and X 20 are bonded to each other
  • Each of the benzene rings preferably has 0 to 3 substituents in total, 1 to 6 substituents.
  • crystallization of the ferroelectric liquid crystal composition can be effectively suppressed, and the liquid crystal display element can be driven stably at a low temperature. Moreover, it can prevent that content of the chiral compound in a ferroelectric liquid-crystal composition is restrict
  • the benzene ring to which X 11 , X 12 , X 17 and X 18 are bonded has two substituents, and the benzene ring to which X 9 , X 10 , X 15 and X 16 are bonded is 1 It preferably has ⁇ 3 substituents. This is because, among the directly bonded benzene rings, the benzene ring located in the middle has a substituent, so that the crystallization of the ferroelectric liquid crystal composition is effectively suppressed.
  • the benzene ring to which X 11 , X 12 , X 17 and X 18 are bonded has two substituents, and X 9 , X
  • the benzene ring to which 10 , X 15 , and X 16 are bonded, or the benzene ring to which X 13 , X 14 , X 19 , and X 20 are bonded preferably has one substituent.
  • the benzene ring to which X 11 , X 12 , X 17 and X 18 are bonded has two substituents, and the benzene ring to which X 9 , X 10 , X 15 and X 16 are bonded.
  • the benzene ring having one substituent has one substituent. This is because, as described above, when the benzene ring located in the middle has a substituent, crystallization of the ferroelectric liquid crystal composition is effectively suppressed.
  • examples of the substituent that the benzene ring has include a benzene ring to which X 9 , X 10 , X 15 and X 16 are bonded, and a benzene ring to which X 13 , X 14 , X 19 and X 20 are bonded.
  • the substituent that is possessed is preferably —CH 3 , —CF 3 or a halogen atom, and more preferably —CH 3 .
  • X 11, X 12, X 17 , substituent group of the benzene ring X 18 is attached is a fluorine atom.
  • X 9 or X 10 is preferably —CH 3
  • X 11 and X 12 are preferably fluorine atoms.
  • chiral compound B represented by the above formula (2) examples include chiral compounds B represented by the following general formulas (2-3) to (2-12).
  • R 12 is a saturated or unsaturated alkyl group having 1 to 10 carbon atoms, * represents a chiral center, and m is 0 or 1.
  • V is 4 to 18, and X 31 to X 34 each independently represent —CH 3 , —CF 3 or a halogen atom, and r, s and in the above formulas (2-3) to (2-6) t is any one or two and the rest is 0, and one of u and w in the above formulas (2-7) to (2-10) is 1 and the other is 0.
  • v is 4 to 18, preferably 6 to 18, and more preferably 6 to 12.
  • the number of carbon atoms is larger than the above range, the synthesis of chiral compound B becomes difficult.
  • the ferroelectric liquid crystal composition may not exhibit a smectic phase.
  • R 12 is a saturated or unsaturated alkyl group having 1 to 10 carbon atoms.
  • the alkyl group is linear, branched or cyclic. Among them, R 12 is preferably a linear or branched saturated alkyl group or a phenylalkyl group.
  • X 31 to X 34 each independently represent —CH 3 , —CF 3 or a halogen atom. . Among them, —CH 3 , a fluorine atom or a chlorine atom is preferable, and —CH 3 or a fluorine atom is particularly preferable.
  • the positions of X 31 to X 34 are the same as the positions of X 9 to X 20 described above.
  • chiral compound B represented by the above formulas (2-3) to (2-6) include a chiral compound B represented by the following formula.
  • chiral compound B represented by the above formulas (2-7) to (2-10) include a chiral compound B represented by the following formula.
  • dextrorotatory property is indicated by (+)
  • levorotatory property is indicated by ( ⁇ ).
  • chiral compound B represented by the above formula (2-11) examples include a chiral compound B represented by the following formula.
  • the ferroelectric liquid crystal composition may contain a chiral compound B represented by the above formula (2-1) and a chiral compound B represented by the above formula (2-2).
  • the content of the chiral compound B in the ferroelectric liquid crystal composition is not particularly limited as long as an impact resistance effect is obtained.
  • the content of the chiral compound B is ferroelectric.
  • each content of the two or more chiral compounds B is ferroelectric. It is preferable that it is 5 mass% or more in a crystalline liquid crystal composition.
  • Chiral compound B can be synthesized, for example, by the method described in International Publication No. 2010/031431.
  • the ferroelectric liquid crystal composition only needs to contain at least one of the chiral compound A and the chiral compound B.
  • the ferroelectric liquid crystal composition may contain only the chiral compound A or only the chiral compound B. It may contain, and the chiral compound A and the chiral compound B may be contained.
  • the ferroelectric liquid crystal composition may contain one kind of chiral compound A or two or more kinds of chiral compounds A.
  • the ferroelectric liquid crystal composition contains the chiral compound B, it may contain one kind of chiral compound B or may contain two or more kinds of chiral compounds B.
  • the content of the chiral compound A in the ferroelectric liquid crystal composition is particularly limited as long as an impact resistance effect is obtained. is not.
  • the content of the chiral compound A is ferroelectric.
  • each content of two or more of the chiral compounds A is ferroelectric. It is preferable that it is 5 mass% or more in a crystalline liquid crystal composition.
  • the chiral compound A when used alone, the content of the chiral compound A is, and when two or more chiral compounds A are mixed, the total content of the two or more chiral compounds A is In the ferroelectric liquid crystal composition, it is preferably in the range of 5% by mass to 35% by mass, and more preferably in the range of 15% by mass to 30% by mass. If the content of the chiral compound A is less than the above range, the desired impact resistance may not be obtained. On the other hand, if the content of the chiral compound A is more than the above range, the ferroelectric liquid crystal composition may be obtained. In some cases, the viscosity becomes high or the crystallized easily, and sufficient impact resistance may not be obtained, and it may be difficult to form a liquid crystal layer when manufacturing a liquid crystal display element. is there.
  • the content of the chiral compound B in the ferroelectric liquid crystal composition is particularly limited as long as an impact resistance effect is obtained. is not.
  • the content of the chiral compound B is ferroelectric.
  • each content of the two or more chiral compounds B is ferroelectric. It is preferable that it is 5 mass% or more in a crystalline liquid crystal composition.
  • the chiral compound B when used alone, the content of the chiral compound B is, and when two or more chiral compounds B are mixed, the total content of the two or more chiral compounds B is: In the ferroelectric liquid crystal composition, it is preferably in the range of 5% by mass to 35% by mass, and more preferably in the range of 15% by mass to 30% by mass. If the content of the chiral compound B is less than the above range, the desired impact resistance may not be obtained. On the other hand, if the content of the chiral compound B is more than the above range, the ferroelectric liquid crystal composition may be obtained. In some cases, the viscosity becomes high or the crystallized easily, and sufficient impact resistance may not be obtained, and it may be difficult to form a liquid crystal layer when manufacturing a liquid crystal display element. is there.
  • the ferroelectric liquid crystal composition contains only the chiral compound B, the chiral compound B1 in which four benzene rings represented by the above formula (2-1) are directly bonded and the above formula (2) -2), the chiral compound B1 in the ferroelectric liquid crystal composition contains the chiral compound B2 in which four benzene rings and one cyclohexane ring directly bonded to each other are contained. It is preferable that it is more than the content of B2.
  • the chiral compound B2 Since the chiral compound B2 has a tendency to reduce the tilt angle of the liquid crystal molecules when a voltage is applied as compared with the chiral compound B1, if the content of the chiral compound B2 is increased compared to the chiral compound B1, the liquid crystal molecules There is a possibility that the tilt angle becomes small and sufficient brightness cannot be obtained. On the other hand, when the chiral compound B1 is contained in a larger amount than the chiral compound B2, the tilt angle of the liquid crystal molecules can be increased, and the driving performance can be improved.
  • the total content of the chiral compound A and the chiral compound B in the ferroelectric liquid crystal composition is such that an impact resistance effect is obtained. If it is, it is not particularly limited, but it is preferably in the range of 5 to 35% by mass, more preferably in the range of 15 to 30% by mass. If the total content of chiral compound A and chiral compound B is less than the above range, the desired impact resistance may not be obtained, while the total content of chiral compound A and chiral compound B is more than the above range. In some cases, the ferroelectric liquid crystal composition has a high viscosity or is easily crystallized, so that sufficient impact resistance may not be obtained. In addition, when a liquid crystal display device is produced, a liquid crystal layer is formed. This may be difficult.
  • the content of the chiral compound B in the ferroelectric liquid crystal composition is preferably not less than the content of the chiral compound A. Since the chiral compound A has a tendency to reduce the tilt angle of the liquid crystal molecules when a voltage is applied as compared with the chiral compound B, if the content of the chiral compound A is increased compared to the chiral compound B, the liquid crystal molecules There is a possibility that the tilt angle becomes small and sufficient brightness cannot be obtained. On the other hand, when the chiral compound B is contained in a larger amount than the chiral compound A, the tilt angle of the liquid crystal molecules can be increased and the driving performance can be improved.
  • the ferroelectric liquid crystal composition in the present invention may contain a host liquid crystal in addition to the chiral compound.
  • host liquid crystal those generally used as the host liquid crystal of the ferroelectric liquid crystal composition can be used, and examples thereof include a phenylpyrimidine compound.
  • a host liquid crystal may be used individually by 1 type, and 2 or more types may be mixed and used for it.
  • the phenylpyrimidine compound used as the host liquid crystal is preferably a phenyl group substituted with a fluorine atom, and more preferably a phenyl group substituted with one or two fluorine atoms.
  • the phase transition temperature of the smectic liquid crystal in the ferroelectric liquid crystal composition is widened, so that the liquid crystal display element can be driven stably at low and high temperatures. It is. Further, since the viscosity of the ferroelectric liquid crystal composition is lowered, there is an advantage that the liquid crystal layer can be easily formed in the manufacturing process of the liquid crystal display element.
  • a ferroelectric liquid crystal composition when applied or dropped when a liquid crystal display device is produced by using a phenylpyrimidine compound in which the phenyl group is substituted with a fluorine atom, the coating mark and the dropping mark are not observed. Since it becomes difficult to occur, it is possible to prevent alignment disorder of liquid crystal molecules due to coating marks and dropping marks, and to suppress the occurrence of alignment defects. This is because the fluorine atom weakens the interaction between the ferroelectric liquid crystal composition and the alignment film, and when the ferroelectric liquid crystal composition is applied or dropped, the liquid crystal molecules are not aligned and are fixed to the alignment film. It is guessed that this is because it is suppressed.
  • phenylpyrimidine compounds include those represented by the following general formulas (4-1) to (4-4).
  • R 21 is an alkyl group
  • R 22 is an alkoxy group or a carboxyl group.
  • the phenylpyrimidine compound is a bicyclic compound having one pyrimidine ring and one benzene ring, a tricyclic compound having one pyrimidine ring and two benzene rings, one pyrimidine ring and 1 Any of a tricyclic compound having one benzene ring and one cyclohexane ring may be used. Especially, as a phenyl pyrimidine compound, it is preferable to mix the said tricyclic compound with the said bicyclic compound.
  • the phase transition temperature of the chiral smectic C phase of the ferroelectric liquid crystal composition is increased. This is because the usable range is widened when used for a display element.
  • the content of the host liquid crystal in the ferroelectric liquid crystal composition is not particularly limited as long as the content of the chiral compound can be within the above range.
  • the phenylpyrimidine compound is a compound in which the phenyl group is substituted with a fluorine atom
  • the content of the phenylpyrimidine compound in the ferroelectric liquid crystal composition is in the range of 10% by mass to 30% by mass. It is preferable. This is because if the content of the phenylpyrimidine compound is small, the above effects may not be sufficiently obtained.
  • the ferroelectric liquid crystal composition is easily crystallized, so that the storage stability is deteriorated and the compound contained in the ferroelectric liquid crystal composition is precipitated, resulting in display quality. It is because there exists a possibility that it may fall.
  • the ferroelectric liquid crystal composition in the present invention is not particularly limited as long as it exhibits a chiral smectic C (SmC * ) phase.
  • As the phase series of the ferroelectric liquid crystal composition for example, a phase change between a nematic (N) phase, a cholesteric (Ch) phase, a chiral smectic C (SmC * ) phase and a nematic (N) phase-chiral in the temperature lowering process.
  • Phase change with smectic C (SmC * ) phase Phase change with smectic C (SmC * ) phase, Nematic (N) phase-Smectic A (SmA) phase-Chiral smectic C (SmC * ) phase change, Nematic (N) phase-Cholesteric (Ch) Phase-smectic A (SmA) phase-chiral smectic C (SmC * ) phase and the like.
  • any one showing bistability and one showing monostability can be used.
  • a ferroelectric liquid crystal composition exhibiting monostability is preferable.
  • gradation display is achieved by continuously changing the director of the liquid crystal (inclination of the molecular axis) by changing the voltage and analog-modulating the transmitted light intensity. This is because it becomes possible.
  • the liquid crystal display element is driven by a field sequential color system, it is preferable to use a ferroelectric liquid crystal composition exhibiting monostability.
  • ferroelectric liquid crystal composition exhibiting monostability, it becomes possible to drive by an active matrix method using TFTs, and also to control gradation by voltage modulation, so that high-definition and high-quality display is possible. This is because it can be realized.
  • “showing monostability” means a state where the state of liquid crystal molecules when no voltage is applied is stabilized in one state.
  • the liquid crystal molecules 25 are tilted from the layer normal z and rotate along a cone ridge having a bottom surface perpendicular to the layer normal z. .
  • the tilt angle of the liquid crystal molecules 25 with respect to the layer normal z is referred to as a tilt angle ⁇ .
  • the liquid crystal molecules 25 can operate on the cone between two states inclined by a tilt angle ⁇ ⁇ with respect to the layer normal z.
  • the expression of monostability refers to a state in which the liquid crystal molecules 25 are stabilized in any one state on the cone when no voltage is applied.
  • the ferroelectric liquid crystal composition only needs to exhibit monostability, and exhibits a half V-shaped switching characteristic in which liquid crystal molecules operate only when a positive or negative voltage is applied.
  • a V-shaped switching characteristic in which liquid crystal molecules operate to the same degree with respect to voltage, asymmetric switching in which the operation of liquid crystal molecules for either positive or negative voltage is larger than the operation of liquid crystal molecules for the other polarity voltage Any of those exhibiting properties can be used.
  • those showing the half V-shaped switching characteristics as exemplified in FIGS. 11A and 11B can increase the transmittance even if the cone angle is relatively small.
  • the V-shaped switching characteristics as illustrated in FIG. 11C make the operation of liquid crystal molecules symmetrical with respect to positive and negative voltages, electrical neutrality, and stability. This is preferable. Even asymmetric switching characteristics can be used by devising a driving method.
  • Such a ferroelectric liquid crystal composition can be variously selected from generally known liquid crystal materials according to required characteristics.
  • the ferroelectric liquid crystal composition that expresses the SmC * phase from the Ch phase without passing through the SmA phase is preferable because the change in the operating characteristics with respect to the voltage is small with respect to the temperature change.
  • the liquid crystal layer in the present invention is formed between the first alignment film of the first alignment treatment substrate and the second alignment film of the second alignment treatment substrate, and contains the above-described ferroelectric liquid crystal composition. .
  • the thickness of the liquid crystal layer is preferably in the range of 1.0 ⁇ m to 10.0 ⁇ m, more preferably in the range of 1.3 ⁇ m to 5.0 ⁇ m, and still more preferably in the range of 1.4 ⁇ m to 3.0 ⁇ m. is there. This is because if the thickness of the liquid crystal layer is too thin, the contrast may be lowered. Conversely, if the thickness of the liquid crystal layer is too thick, the liquid crystal molecules may be difficult to align.
  • the thickness of the liquid crystal layer can be adjusted by a bead spacer, a columnar spacer, a partition wall, or the like.
  • a method for forming the liquid crystal layer a method generally used as a method for manufacturing a liquid crystal cell can be used.
  • a vacuum injection method for example, first, a ferroelectric liquid crystal composition made into an isotropic liquid by heating is applied to a liquid crystal cell that has been prepared using a first alignment treatment substrate and a second alignment treatment substrate in advance. Inject using the effect.
  • a liquid crystal layer can be formed by sealing the liquid crystal cell injected with the ferroelectric liquid crystal composition with an adhesive.
  • a heated or room temperature ferroelectric liquid crystal composition is dropped or applied onto the second alignment film of the second alignment processing substrate.
  • a sealant is applied to the peripheral portion of the first alignment processing substrate.
  • a liquid crystal layer can be formed by stacking the first alignment treatment substrate and the second alignment treatment substrate under reduced pressure and bonding them with a sealant.
  • the liquid crystal layer forming method is preferably a liquid crystal dropping method. This is because the liquid crystal display element can be efficiently manufactured by shortening the tact time.
  • the ferroelectric liquid crystal composition when dropped or applied, it is preferably at room temperature. This is because deterioration of the ferroelectric liquid crystal composition due to heat can be prevented.
  • the ferroelectric liquid crystal composition When aligning the ferroelectric liquid crystal composition, it may be cooled, and it is not necessary to apply a voltage to the liquid crystal layer. It is preferable to cool slowly during cooling.
  • the 1st orientation processing board used for the present invention is the 1st base material, the 1st electrode layer formed on the 1st base material, and the 1st orientation formed on the 1st electrode layer. And a film. Since the first alignment film has been described above, the description thereof is omitted here. Hereinafter, another configuration of the first alignment processing substrate will be described.
  • the 1st electrode layer used for this invention will not be specifically limited if it is generally used as an electrode of a liquid crystal display element,
  • Preferred examples of the transparent conductor material include indium oxide, tin oxide, indium tin oxide (ITO), and the like.
  • one of the first alignment processing substrate and the second alignment processing substrate is formed on the entire surface formed of the transparent conductor.
  • An electrode is provided, and on the other side, a gate electrode and a source electrode are arranged in a matrix, and a TFT element and a pixel electrode are provided in a portion surrounded by the gate electrode and the source electrode.
  • Examples of the method for forming the first electrode layer include chemical vapor deposition (CVD), physical vapor deposition (PVD) such as sputtering, ion plating, and vacuum deposition.
  • CVD chemical vapor deposition
  • PVD physical vapor deposition
  • the 1st base material used for this invention will not be specifically limited if generally used as a base material of a liquid crystal display element, For example, a glass plate, a plastic plate, etc. are mentioned preferably.
  • a partition wall or a columnar spacer may be formed on the first base material.
  • the partition or columnar spacer is not formed on the first base material in the first alignment processing substrate. That is, partition walls or columnar spacers may be formed on the first alignment processing substrate, and partition walls or columnar spacers may be formed on the second alignment processing substrate.
  • partition walls and columnar spacers general partition walls and columnar spacers can be applied.
  • the colored layer may be formed on the 1st base material.
  • the coloring layer is not formed on the first base material in the first alignment processing substrate. That is, a colored layer may be formed on the first alignment processing substrate, and a coloring layer may be formed on the second alignment processing substrate.
  • a color filter type liquid crystal display element capable of realizing color display by the colored layer can be obtained.
  • a method for forming the colored layer a method for forming a colored layer in a general color filter can be used. For example, a pigment dispersion method (color resist method, etching method), a printing method, an inkjet method, or the like can be used. it can.
  • the second alignment treatment substrate used in the present invention includes a second base material, a second electrode layer formed on the second base material, and a second orientation formed on the second electrode layer. And a film. Since the second alignment film has been described above, description thereof is omitted here.
  • the second base material, the second electrode layer, and other configurations are the same as the first base material, the first electrode layer, and other configurations in the first alignment processing substrate, respectively. Description is omitted.
  • the liquid crystal display element of the present invention may have a polarizing plate.
  • the polarizing plate used in the present invention is not particularly limited as long as it transmits only a specific direction among the wave of light, and a polarizing plate generally used as a polarizing plate of a liquid crystal display element should be used. Can do.
  • the ferroelectric liquid crystal composition exhibits monostability
  • the second alignment film is relatively the first alignment film and the second alignment film.
  • FIG. 12 is a schematic diagram showing an example of an alignment state of liquid crystal molecules showing monostability and showing half V-shaped switching characteristics.
  • 12A shows a case where no voltage is applied
  • FIG. 12B shows a case where a negative voltage is applied to the second electrode layer
  • FIG. 12C shows a case where a positive voltage is applied to the second electrode layer.
  • Each is shown.
  • the liquid crystal molecules 25 are stabilized in one state on the cone (FIG. 12A).
  • a negative voltage is applied to the second electrode layer, the liquid crystal molecules 25 are tilted from the stabilized state (broken line) to one side (FIG. 12B).
  • the liquid crystal molecules 25 are tilted from the stabilized state (broken line) to the opposite side when a negative voltage is applied to the second electrode layer (see FIG. 12 (c)).
  • the inclination angle ⁇ when a negative voltage is applied to the second electrode layer is larger than the inclination angle ⁇ when a positive voltage is applied to the second electrode layer.
  • D1 and D2 are the rubbing treatment directions of the first alignment film and the second alignment film, respectively, and z is the layer normal.
  • the second alignment film tends to have a relatively positive polarity
  • the inclination angle of the liquid crystal molecules from the mono-stabilized state when the negative voltage of the second electrode layer is applied is
  • the positive voltage of the second electrode layer is applied
  • the inclination angle of the liquid crystal molecules from the mono-stabilized state becomes larger. Therefore, when a negative voltage is applied to the second electrode layer, the amount of transmitted light is larger than when a positive voltage is applied to the second electrode layer. That is, when a positive voltage is applied to the second electrode layer, the amount of transmitted light is less than when a negative voltage is applied to the second electrode layer.
  • “Display when a negative voltage is applied to the second electrode layer” means that liquid crystal molecules are stabilized in one state on the cone when no voltage is applied, and the second electrode layer is negative.
  • the liquid crystal molecules tilt from the mono-stabilized state to one side on the cone, and the liquid crystal molecules maintain the mono-stabilized state when a positive voltage is applied to the second electrode layer.
  • tilted from the mono-stabilized state to the opposite side of the negative voltage applied to the second electrode layer and tilted from the mono-stabilized state of the liquid crystal molecules when a negative voltage is applied to the second electrode layer. It means that the angle is larger than the tilt angle from the mono-stabilized state of the liquid crystal molecules when a positive voltage is applied to the second electrode layer.
  • the alignment direction in the mono-stabilized state of the liquid crystal molecules and the polarization axis of one polarizing plate are made substantially parallel.
  • the spontaneous polarization Ps of the liquid crystal molecules 25 tends to face the first alignment film 4a side.
  • the liquid crystal molecules 25 are aligned along the alignment treatment directions D1 and D2 of the first alignment film and the second alignment film, thereby obtaining a uniform alignment state.
  • the spontaneous polarization Ps of the liquid crystal molecules 25 is directed to the second alignment film 4b side due to the influence of the polarity of the applied voltage, as illustrated in FIG. .
  • the liquid crystal molecules 25 are in a uniform alignment state as illustrated in FIG. Furthermore, when a positive voltage is applied to the second electrode layer 3b, the spontaneous polarization Ps of the liquid crystal molecules 25 is directed toward the first alignment film 4a due to the influence of the polarity of the applied voltage, as illustrated in FIG. . In this case, the direction of spontaneous polarization is the same as that in the state where no voltage is applied. As described above, the direction of the spontaneous polarization is the direction in which the polarization of the liquid crystal molecules and the polarization of the alignment film or the polarity of the voltage are electrically balanced. This is because of an electrically stable state.
  • FIG. 13A is a schematic diagram showing the alignment state of the liquid crystal molecules from the upper surface of FIG.
  • FIG. 13B is a schematic diagram showing the alignment state of the liquid crystal molecules from the upper surface of FIG. 9, and the spontaneous polarization Ps is directed from the back of the page to the near side (the mark ⁇ in FIG. 13B). ).
  • the spontaneous polarization of the liquid crystal molecules tends to be directed to the first alignment film side.
  • a liquid crystal display element using a ferroelectric liquid crystal composition exhibiting V-shaped switching characteristics or asymmetric switching characteristics can be driven by controlling the direction of spontaneous polarization of liquid crystal molecules in the same manner. .
  • the second electrode layer When a negative voltage is applied to the second electrode layer, there are preferably 70% or more, more preferably 80% or more, more preferably 90% or more, in which the molecular direction of the liquid crystal changes about twice the tilt angle. Most preferably, it is 95% or more. This is because a favorable contrast ratio can be obtained within the above range.
  • said ratio can be measured as follows.
  • polarizing plates 17a and 17b are provided on the outer sides of the first alignment processing substrate 11a and the second alignment processing substrate 11b, respectively, and the two polarizing plates 17a and 17b have substantially vertical polarization axes.
  • a liquid crystal display element is used in which the polarization axis of the polarizing plate 17a and the rubbing treatment direction (the alignment direction of liquid crystal molecules) of the first alignment film 4a are substantially parallel. A dark state is obtained when no voltage is applied, and a bright state is obtained when a voltage is applied. When a negative voltage is applied to the second electrode layer, a bright state is obtained when the molecular direction of the liquid crystal changes approximately twice the tilt angle.
  • the liquid crystal molecules When a negative voltage is applied to the second electrode layer, the liquid crystal molecules are inclined from the mono-stabilized state to one side on the cone at an angle corresponding to the magnitude of the applied voltage. Further, in the ferroelectric liquid crystal, as illustrated in FIG. 12A, the position A (direction of the liquid crystal molecules 25), the position B (rubbing treatment directions D1, D2), and the position C are not necessarily coincident. Do not mean. Therefore, as illustrated in FIG. 12B, the maximum tilt angle ⁇ when a negative voltage is applied to the second electrode layer is about twice the tilt angle ⁇ .
  • the angle at which the molecular direction of the liquid crystal changes parallel to the first alignment treatment substrate surface can be measured as follows. First, a polarizing microscope and a liquid crystal display element in which polarizing plates are arranged in crossed Nicols are arranged so that the polarization axis of one polarizing plate and the alignment direction of liquid crystal molecules in the liquid crystal layer are parallel, and this position is used as a reference. . When a voltage is applied, the liquid crystal molecules come to have a predetermined angle with the polarization axis, so that the polarized light transmitted through one polarizing plate is transmitted through the other polarizing plate to be in a bright state. With this voltage applied, the liquid crystal display element is rotated to a dark state. And the angle which rotated the liquid crystal display element at this time is measured. The angle by which the liquid crystal display element is rotated is an angle at which the molecular direction of the liquid crystal changes in parallel to the first alignment processing substrate surface.
  • the liquid crystal molecules are inclined from the mono-stabilized state to one side on the cone at an angle according to the magnitude of the applied voltage.
  • the direction of the liquid crystal molecules does not change about twice the tilt angle when a negative voltage is applied to the second electrode layer.
  • the amount of transmitted light depends on the tilt angle of liquid crystal molecules when a voltage is applied.
  • the liquid crystal molecules are tilted on the cone, so that, for example, as shown in FIG.
  • the amount of transmitted light is maximized when the inclination angle of the liquid crystal molecules from the monostable state is 45 °. Therefore, in order to realize a high amount of transmitted light, a ferroelectric liquid crystal whose tilt angle from a monostable state of liquid crystal molecules can be 45 ° when a negative voltage is applied to the second electrode layer during actual driving. It is preferable to use a composition.
  • the liquid crystal display element is actually driven.
  • the tilt angle of the liquid crystal molecules from the monostable state can be set to 45 °. This is because, as described above, when a negative voltage is applied to the second electrode layer during actual driving, the direction of the liquid crystal molecules does not change approximately twice the tilt angle.
  • the high-speed response of the ferroelectric liquid crystal composition can be used.
  • it can be suitably used for a required field sequential color system.
  • the driving method of the liquid crystal display element of the present invention is not limited to the field sequential method, and may be a color filter method that performs color display using a colored layer.
  • an active matrix method using a thin film transistor is preferable. This is because by adopting an active matrix system using TFTs, the target pixel can be reliably turned on and off, and a high-quality display becomes possible.
  • the first alignment treatment substrate may be a TFT substrate
  • the second alignment treatment substrate may be a common electrode substrate
  • the first alignment treatment substrate is a common electrode substrate
  • the second alignment treatment substrate is a TFT substrate.
  • the first alignment process substrate is common to the TFT substrate and the second alignment process substrate.
  • An electrode substrate is preferred.
  • the TFT element 27 when the gate electrode 26x is set to a high potential of about 30V, the TFT element 27 is switched on, and the signal voltage is applied to the ferroelectric liquid crystal composition by the source electrode 26y.
  • the electrode 26x When the electrode 26x is set to a low potential of about ⁇ 10V, the TFT element 27 is switched off.
  • a voltage is applied between the common electrode (second electrode layer 3b) and the gate electrode 26x so that the common electrode (second electrode layer 3b) side is positive. .
  • the liquid crystal molecules do not operate, so that the pixel is in a dark state.
  • the spontaneous polarization of the liquid crystal molecules is caused by the polar surface interaction in the no voltage applied state.
  • the spontaneous polarization Ps of the liquid crystal molecules 25 faces the TFT substrate (first alignment processing substrate 11a) side. Therefore, the direction of spontaneous polarization is not affected by the voltage applied between the common electrode (second electrode layer 3b) and the gate electrode 26x. Therefore, by controlling the direction of spontaneous polarization and using the first alignment processing substrate as the TFT substrate and the second alignment processing substrate as the common electrode substrate, light leakage near the gate electrode can be prevented.
  • the driving method of the liquid crystal display element of the present invention may be a segment method.
  • the present invention is not limited to the above embodiment.
  • the above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.
  • Example 1 Ferroelectric liquid crystal composition
  • Ferroelectric liquid crystal compositions were prepared as shown in Table 1 below using ab of chiral compound A and 1-2 of chiral compound B shown below.
  • the above-mentioned ferroelectric liquid crystal composition was applied in the form of dots, and the two substrates were assembled and thermocompression bonded so that the rubbing treatment direction was parallel and parallel or antiparallel. Thereafter, the liquid crystal cell was cooled to align the ferroelectric liquid crystal composition.
  • Example 2 Ferroelectric liquid crystal composition
  • a ferroelectric liquid crystal composition was prepared in the same manner as in Example 1 except that c to h of chiral compound A and 3 to 8 of chiral compound B shown in Table 3 were used.
  • the total content of chiral compounds was 15% by mass, the content of each of the host liquid crystals I to III was 28.3% by mass.
  • the dextrorotatory property is indicated by (+) and the levorotatory property is indicated by ( ⁇ ).
  • a liquid crystal display element was produced in the same manner as in Example 1.
  • either of the chiral compounds contained in the ferroelectric liquid crystal composition is compared with the case where the chiral compound contained in the ferroelectric liquid crystal composition does not have two fluorine atoms in the substituent.
  • the tilt angle was increased when this chiral compound had two fluorine atoms in the substituent.
  • the chiral compound contained in the ferroelectric liquid crystal composition is compared with the case where any one of the chiral compounds has two fluorine atoms in the substituent. In any case, the tilt angle was larger when the substituent had two fluorine atoms.
  • the transmittance is calculated from the tilt angle, and is a value when the transmittance when the tilt angle is 45 degrees is 100%. This value is an average value of transmittance when a positive voltage (+10 V) is applied and transmittance when a negative voltage ( ⁇ 10 V) is applied. As a result of the measurement, the transmittance increased with the above-described tilt angle, and the same tendency as the tilt angle was obtained. Tables 4 and 5 show the evaluation results of orientation, tilt angle, and transmittance.

Abstract

The primary objective of the present invention is to provide a liquid crystal display element that has superior display quality when using a ferroelectric liquid crystal composition that can exhibit impact resistance. The present invention provides a liquid crystal display element having: a first orientation-processed substrate having a first substrate, a first electrode layer formed on the first substrate, and a first oriented film formed on the first electrode layer and subjected to rubbing processing; a second orientation-processed substrate having a second substrate, a second electrode layer formed on the second substrate, and a second oriented film formed on the second electrode layer and subjected to rubbing processing; and a liquid crystal layer formed between the first orientation-processed substrate and the second orientation-processed substrate and containing a ferroelectric liquid crystal composition. The liquid crystal display element is characterized by the first oriented film and the second oriented film being disposed in a manner so that the directions of rubbing processing are parallel, and the ferroelectric liquid crystal composition containing a chiral compound (A) represented by general formula (1) and/or a chiral compound (B) represented by general formula (2).

Description

液晶表示素子Liquid crystal display element
　本発明は、強誘電性液晶組成物を用いた液晶表示素子に関するものである。 The present invention relates to a liquid crystal display element using a ferroelectric liquid crystal composition.
　液晶表示素子は薄型で低消費電力などといった特徴から、大型ディスプレイから携帯情報端末までその用途を広げており、その開発が活発に行われている。これまで液晶表示素子は、ＴＮ方式、ＳＴＮのマルチプレックス駆動、ＴＮに薄層トランジスタ（ＴＦＴ）を用いたアクティブマトリックス駆動等が開発され実用化されているが、これらはネマチック液晶を用いているために、液晶材料の応答速度が数ｍｓ～数十ｍｓと遅く、動画表示に充分対応しているとはいえない。 Liquid crystal display elements are widely used from large displays to portable information terminals because of their thinness and low power consumption, and their development is actively underway. So far, liquid crystal display elements have been developed and put to practical use, such as TN mode, STN multiplex drive, and active matrix drive using thin layer transistors (TFTs) for TN, but these use nematic liquid crystals. In addition, the response speed of the liquid crystal material is as slow as several ms to several tens of ms, and it cannot be said that it is sufficiently compatible with moving image display.
　強誘電性液晶は、応答速度がμｓオーダーと極めて短く、高速デバイスに適した液晶であり、視野角が広いなどの優位性を有するため、高性能な液晶表示素子が提供できるとして期待されている。
　しかしながら、強誘電性液晶は、ネマチック液晶に比べて分子の秩序性が高いために、衝撃により分子配向の規則性が乱されると元の状態に戻りにくい、すなわち外部衝撃に非常に弱いという問題を抱えている。 Ferroelectric liquid crystal is expected to provide a high-performance liquid crystal display element because it has a superior response speed such as a wide viewing angle because it has a response speed as short as μs and is suitable for high-speed devices. .
However, the ferroelectric liquid crystal has a higher molecular order than the nematic liquid crystal, so that it is difficult to return to its original state when the regularity of molecular orientation is disturbed by impact, that is, it is very weak to external impact. Have
　耐衝撃性を向上させる手段としては、例えば、一対の基板間に隔壁（リブとも称する。）を配置する方法が提案されている（例えば特許文献１および特許文献２参照）。しかしながら、隔壁が設けられている場合であっても、液晶表示素子に局所的に衝撃が加わった場合には、配向乱れが生じてしまうという問題がある。
　また、耐衝撃性を向上させる手段として、例えば、強誘電性液晶組成物にゲル化剤を添加する方法（特許文献３参照）、強誘電性液晶組成物に硬化型樹脂を添加する方法、強誘電性液晶組成物に熱可塑性樹脂を添加する方法（特許文献４参照）、強誘電性液晶構造を側鎖に有する強誘電性高分子液晶を用いる方法、液晶高分子化合物と低分子の強誘電性液晶化合物を混合する方法（特許文献５参照）が提案されている。しかしながら、これらの方法では、駆動電圧が高くなるという問題がある。また、強誘電性液晶組成物に高分子化合物を用いたとしても、ある程度の弱い衝撃に対して分子配向の規則性が乱れにくくなるという効果は示すものの、強い衝撃によって配向の規則性が乱れると元の状態に戻りにくいという本質的な問題は解決されていない。 As means for improving the impact resistance, for example, a method of arranging a partition wall (also referred to as a rib) between a pair of substrates has been proposed (see, for example, Patent Document 1 and Patent Document 2). However, even when the partition walls are provided, there is a problem that alignment disturbance occurs when a shock is locally applied to the liquid crystal display element.
Further, as means for improving impact resistance, for example, a method of adding a gelling agent to a ferroelectric liquid crystal composition (see Patent Document 3), a method of adding a curable resin to a ferroelectric liquid crystal composition, A method of adding a thermoplastic resin to a dielectric liquid crystal composition (see Patent Document 4), a method using a ferroelectric polymer liquid crystal having a ferroelectric liquid crystal structure in the side chain, a liquid crystal polymer compound and a low molecular ferroelectric A method of mixing a conductive liquid crystal compound (see Patent Document 5) has been proposed. However, these methods have a problem that the drive voltage becomes high. In addition, even if a polymer compound is used for the ferroelectric liquid crystal composition, the regularity of the molecular orientation is less likely to be disturbed to a certain degree of weak impact, but the orientation regularity is disturbed by a strong impact. The essential problem that it is difficult to return to the original state has not been solved.
　最近では、耐衝撃性の向上を目的として、強誘電性液晶組成物自体の耐衝撃性を高める試みがなされており、強誘電性液晶組成物に用いるキラル化合物の構造が種々検討されている（特許文献６参照）。特許文献６によれば、４個のベンゼン環が直接結合された所定の構造を有するキラル化合物を含有する強誘電性液晶組成物を用いた場合には、衝撃を加えた後でもコントラスト比が良好であったことが報告されている。 Recently, attempts have been made to increase the impact resistance of the ferroelectric liquid crystal composition itself for the purpose of improving the impact resistance, and various structures of chiral compounds used in the ferroelectric liquid crystal composition have been studied ( (See Patent Document 6). According to Patent Document 6, when a ferroelectric liquid crystal composition containing a chiral compound having a predetermined structure in which four benzene rings are directly bonded is used, the contrast ratio is good even after an impact is applied. It has been reported that
　ところで、強誘電性液晶組成物を用いた液晶表示素子において、ラビング処理された一対の配向膜はラビング処理方向が平行になるように配置されるのが一般的である。この際、ラビング処理された配向膜を、ラビング処理方向が平行かつ同一方向（パラレルとも称する。）となるように配置する場合と、ラビング処理方向が平行かつ反対方向（アンチパラレルとも称する。）となるように配置する場合とがある。
　従来では、アンチパラレルとなるように配置されることが好ましいとされている（例えば特許文献７参照）。これは、図１９（ａ）、（ｂ）に例示するようにラビング処理された配向膜１００ａ，１００ｂによって液晶分子１０１はプレチルトが付与されるため、図１９（ａ）に例示するようにラビング処理された配向膜１００ａ，１００ｂをラビング処理方向Ｄ１，Ｄ２が平行かつ同一方向（パラレル）となるように配置するよりも、図１９（ｂ）に例示するようにラビング処理された配向膜１００ａ，１００ｂをラビング処理方向Ｄ１，Ｄ２が平行かつ反対方向（アンチパラレル）となるように配置するほうが、配向欠陥が発生し難く、均一な配向が得られると考えられるからである。 By the way, in a liquid crystal display element using a ferroelectric liquid crystal composition, a pair of rubbing alignment films is generally arranged so that the rubbing treatment directions are parallel. At this time, the alignment films subjected to the rubbing treatment are arranged so that the rubbing treatment directions are parallel and the same direction (also referred to as parallel), and the rubbing treatment directions are parallel and opposite directions (also referred to as anti-parallel). It may be arranged to be.
Conventionally, it has been preferable to be arranged in an antiparallel manner (see, for example, Patent Document 7). This is because the liquid crystal molecules 101 are given a pretilt by the alignment films 100a and 100b subjected to the rubbing process as illustrated in FIGS. 19A and 19B, and thus the rubbing process as illustrated in FIG. 19A. The alignment films 100a and 100b subjected to the rubbing treatment as illustrated in FIG. 19B, rather than the alignment films 100a and 100b thus arranged so that the rubbing treatment directions D1 and D2 are parallel and in the same direction (parallel). This is because it is considered that the alignment defects are less likely to occur and the uniform alignment can be obtained when the rubbing treatment directions D1 and D2 are arranged in parallel and in opposite directions (anti-parallel).
特開２００４－７７５４１号公報JP 2004-77541 A 国際公開第０２／０３１３１号パンフレットInternational Publication No. 02/03131 Pamphlet 特開２００４－２３３４１４号公報JP 2004-233414 A 特開２００３－１１４４４０号公報JP 2003-114440 A 特許第３５４１４３７号公報Japanese Patent No. 3541437 国際公開第２０１０／０３１４３１号パンフレットInternational Publication No. 2010/031431 Pamphlet 特開２００６－２２０６７５号公報JP 2006-220675 A
　そこで、本発明者らは、耐衝撃性を発揮し得る強誘電性液晶組成物を用いて、ラビング処理された配向膜をアンチパラレルに配置した液晶表示素子を作製した。しかしながら、種々のラビング配向膜の組合せで液晶表示素子を作製したところ、ほとんどのラビング配向膜の組合せで濃淡が明らかに異なる二つのドメインが発生し、これが表示品質を低下させることがわかった。
　本発明は、上記実情に鑑みてなされたものであり、耐衝撃性を発揮し得る強誘電性液晶組成物を用いた場合に、表示品質に優れる液晶表示素子を提供することを主目的とするものである。 Therefore, the present inventors produced a liquid crystal display element in which rubbing-treated alignment films were arranged in antiparallel using a ferroelectric liquid crystal composition capable of exhibiting impact resistance. However, when liquid crystal display elements were fabricated by combining various rubbing alignment films, it was found that almost all combinations of rubbing alignment films generated two domains with distinctly different shades, which deteriorated display quality.
The present invention has been made in view of the above circumstances, and a main object of the present invention is to provide a liquid crystal display device having excellent display quality when a ferroelectric liquid crystal composition capable of exhibiting impact resistance is used. Is.
　本発明者らは、強誘電性液晶組成物を用いた液晶表示素子の耐衝撃性について種々検討を重ねた結果、耐衝撃性を発揮し得る強誘電性液晶組成物を用いた場合に、従来の好ましい態様とは逆に、ラビング処理された配向膜をパラレルに配置することで、異なるドメインによる表示品質の低下を防ぎ、高品質な画像表示を実現できることを見出し、このような知見に基づいて本発明を完成させるに至った。 As a result of various studies on impact resistance of a liquid crystal display device using a ferroelectric liquid crystal composition, the present inventors have found that when a ferroelectric liquid crystal composition capable of exhibiting impact resistance is used, Contrary to the preferred embodiment of the above, it has been found that by arranging the alignment films subjected to the rubbing treatment in parallel, it is possible to prevent deterioration in display quality due to different domains and realize high-quality image display. The present invention has been completed.
　すなわち、本発明は、第１基材、上記第１基材上に形成された第１電極層、および、上記第１電極層上に形成され、ラビング処理された第１配向膜を有する第１配向処理基板と、第２基材、上記第２基材上に形成された第２電極層、および、上記第２電極層上に形成され、ラビング処理された第２配向膜を有する第２配向処理基板と、上記第１配向膜および上記第２配向膜の間に形成され、強誘電性液晶組成物を含む液晶層とを有する液晶表示素子であって、上記第１配向膜および上記第２配向膜はラビング処理方向がパラレルとなるように配置されており、上記強誘電性液晶組成物は、下記一般式（１）で表されるキラル化合物Ａおよび下記一般式（２）で表されるキラル化合物Ｂの少なくともいずれかのキラル化合物を含有することを特徴とする液晶表示素子を提供する。 That is, the present invention includes a first base material, a first electrode layer formed on the first base material, and a first alignment film formed on the first electrode layer and rubbed. A second alignment having an alignment substrate, a second substrate, a second electrode layer formed on the second substrate, and a second alignment film formed on the second electrode layer and rubbed. A liquid crystal display element having a processing substrate and a liquid crystal layer formed between the first alignment film and the second alignment film and containing a ferroelectric liquid crystal composition, wherein the first alignment film and the second alignment film The alignment film is arranged so that the rubbing treatment direction is parallel, and the ferroelectric liquid crystal composition is represented by the chiral compound A represented by the following general formula (1) and the following general formula (2). Containing at least one chiral compound of chiral compound B To provide a liquid crystal display element according to symptoms.
Figure JPOXMLDOC01-appb-C000004
Figure JPOXMLDOC01-appb-C000004
（上記式（１）において、Ｒ1は、非キラルな基であり、ハロゲン原子で置換されていてもよい炭素数４～１８の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
Ｒ２は、キラルな基であり、下記一般式（３）で表される基である。 (In the above formula (1), R 1 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
R 2 is a chiral group and is a group represented by the following general formula (3).
Figure JPOXMLDOC01-appb-C000005
Figure JPOXMLDOC01-appb-C000005
（上記式（３）において、Ｒ３は、ハロゲン原子で置換されていてもよい炭素数１～１０の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
Ｙ１は、－ＣＨ３またはフッ素原子を表す。ｍは０または１である。ｎは０または１である。＊印はキラル中心を示す。）
Ｘ１～Ｘ８は、それぞれ独立して－ＣＨ３、－ＣＦ３、ハロゲン原子または水素原子を表す。ただし、Ｘ１～Ｘ８のうち１つ以上は、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子である。） (In the above formula (3), R 3 is a saturated or unsaturated alkyl or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
Y 1 represents —CH 3 or a fluorine atom. m is 0 or 1. n is 0 or 1. * Indicates a chiral center. )
X 1 to X 8 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 1 to X 8 are each independently —CH 3 , —CF 3 or a halogen atom. )
Figure JPOXMLDOC01-appb-C000006
Figure JPOXMLDOC01-appb-C000006
（上記式（２）において、Ｒ４は、非キラルな基であり、ハロゲン原子で置換されていてもよい炭素数４～１８の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
Ｒ５は、キラルな基であり、上記式（３）で表される基である。
Ｘ９～Ｘ２０は、それぞれ独立して－ＣＨ３、－ＣＦ３、ハロゲン原子または水素原子を表す。ただし、Ｘ９～Ｘ２０のうち１つ以上は、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子である。
Ｋは、単結合またはシクロヘキサン環を表す。） (In the above formula (2), R 4 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
R 5 is a chiral group, and is a group represented by the above formula (3).
X 9 to X 20 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 9 to X 20 are each independently —CH 3 , —CF 3 or a halogen atom.
K represents a single bond or a cyclohexane ring. )
　本発明によれば、上記式（１）で表されるキラル化合物Ａおよび上記式（２）で表されるキラル化合物Ｂの少なくともいずれかのキラル化合物を含有し、耐衝撃性を発揮し得る強誘電性液晶組成物を用いた場合に、第１配向膜および第２配向膜がラビング処理方向がパラレルとなるように配置されていることにより、表示品質に優れる液晶表示素子とすることが可能となる。 According to the present invention, the compound contains at least one chiral compound of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2), and is capable of exhibiting impact resistance. When the dielectric liquid crystal composition is used, the first alignment film and the second alignment film are arranged so that the rubbing treatment directions are parallel, thereby enabling a liquid crystal display element having excellent display quality. Become.
　上記発明においては、上記第１配向膜の構成材料および上記第２配向膜の構成材料が互いに異なる組成を有することが好ましい。配向欠陥の発生を抑制し、コントラストを向上させることができるからである。 In the above invention, the constituent material of the first alignment film and the constituent material of the second alignment film preferably have different compositions. This is because the occurrence of alignment defects can be suppressed and the contrast can be improved.
　本発明においては、上記式（１）で表されるキラル化合物Ａおよび上記式（２）で表されるキラル化合物Ｂの少なくともいずれかのキラル化合物を含有し、耐衝撃性を発揮し得る強誘電性液晶組成物を用いた場合に、第１配向膜および第２配向膜がラビング処理方向がパラレルとなるように配置されていることにより、表示品質に優れる液晶表示素子とすることができるという効果を奏する。 In the present invention, a ferroelectric compound containing at least one of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2) and exhibiting impact resistance When the first liquid crystal composition is used, the first alignment film and the second alignment film are arranged so that the rubbing treatment directions are parallel, whereby the liquid crystal display element having excellent display quality can be obtained. Play.
本発明の液晶表示素子の一例を示す概略断面図である。It is a schematic sectional drawing which shows an example of the liquid crystal display element of this invention. 双安定性を示す強誘電性液晶組成物における液晶分子の配向状態の一例を示す模式図である。It is a schematic diagram which shows an example of the orientation state of the liquid crystal molecule in the ferroelectric liquid crystal composition which shows bistability. シェブロン構造を説明するための模式図である。It is a schematic diagram for demonstrating a chevron structure. ブックシェルフ構造を説明するための模式図である。It is a schematic diagram for demonstrating a bookshelf structure. 単安定性を示し、かつハーフＶ字型スイッチング特性を有する強誘電性液晶組成物における液晶分子の配向状態の一例を示す模式図である。It is a schematic diagram which shows an example of the orientation state of the liquid crystal molecule in the ferroelectric liquid crystal composition which shows monostability and has a half V-shaped switching characteristic. 本発明における液晶分子の配向状態の一例を示す模式図である。It is a schematic diagram which shows an example of the orientation state of the liquid crystal molecule in this invention. パラレルおよびアンチパラレルの液晶表示素子における液晶分子の配向状態の一例を示す模式図である。It is a schematic diagram which shows an example of the orientation state of the liquid crystal molecule in a parallel and antiparallel liquid crystal display element. 液晶分子の配向状態の一例を示す模式図である。It is a schematic diagram which shows an example of the orientation state of a liquid crystal molecule. 液晶分子の配向状態の他の例を示す模式図である。It is a schematic diagram which shows the other example of the orientation state of a liquid crystal molecule. 液晶分子の配向状態の他の例を示す模式図である。It is a schematic diagram which shows the other example of the orientation state of a liquid crystal molecule. 液晶表示素子の印加電圧に対する透過光量の変化を示したグラフである。It is the graph which showed the change of the transmitted light quantity with respect to the applied voltage of a liquid crystal display element. 液晶分子の配向状態の他の例を示す模式図である。It is a schematic diagram which shows the other example of the orientation state of a liquid crystal molecule. 液晶分子の配向状態の他の例を示す模式図である。It is a schematic diagram which shows the other example of the orientation state of a liquid crystal molecule. 液晶分子の自発分極を示す模式図である。It is a schematic diagram which shows the spontaneous polarization of a liquid crystal molecule. 本発明の液晶表示素子の他の例を示す概略断面図である。It is a schematic sectional drawing which shows the other example of the liquid crystal display element of this invention. 本発明の液晶表示素子の他の例を示す概略斜視図である。It is a schematic perspective view which shows the other example of the liquid crystal display element of this invention. 液晶分子の配向状態の他の例を示す模式図である。It is a schematic diagram which shows the other example of the orientation state of a liquid crystal molecule. 実施例における液晶配向の評価を説明するための写真である。It is a photograph for demonstrating evaluation of the liquid crystal orientation in an Example. パラレルおよびアンチパラレルの液晶表示素子における液晶分子の配向状態の他の例を示す模式図である。It is a schematic diagram which shows the other example of the orientation state of the liquid crystal molecule in a parallel and antiparallel liquid crystal display element.
　以下、本発明の液晶表示素子について、詳細に説明する。
　本発明の液晶表示素子は、第１基材、上記第１基材上に形成された第１電極層、および、上記第１電極層上に形成され、ラビング処理された第１配向膜を有する第１配向処理基板と、第２基材、上記第２基材上に形成された第２電極層、および、上記第２電極層上に形成され、ラビング処理された第２配向膜を有する第２配向処理基板と、上記第１配向膜および上記第２配向膜の間に形成され、強誘電性液晶組成物を含む液晶層とを有する液晶表示素子であって、上記第１配向膜および上記第２配向膜はラビング処理方向がパラレルとなるように配置されており、上記強誘電性液晶組成物は、上記式（１）で表されるキラル化合物Ａおよび上記式（２）で表されるキラル化合物Ｂの少なくともいずれかのキラル化合物を含有することを特徴とするものである。 Hereinafter, the liquid crystal display element of the present invention will be described in detail.
The liquid crystal display element of the present invention has a first base material, a first electrode layer formed on the first base material, and a first alignment film formed on the first electrode layer and subjected to a rubbing process. A first alignment treatment substrate, a second substrate, a second electrode layer formed on the second substrate, and a second alignment film formed on the second electrode layer and subjected to a rubbing treatment A liquid crystal display element having a two-alignment-treated substrate and a liquid crystal layer formed between the first alignment film and the second alignment film and containing a ferroelectric liquid crystal composition, wherein the first alignment film and the above-mentioned The second alignment film is arranged so that the rubbing treatment direction is parallel, and the ferroelectric liquid crystal composition is represented by the chiral compound A represented by the above formula (1) and the above formula (2). Containing at least one chiral compound of chiral compound B, Is shall.
　本発明の液晶表示素子について図面を参照しながら説明する。
　図１は、本発明の液晶表示素子の一例を示す概略断面図である。図１に例示するように、液晶表示素子１は、第１基材２ａ上に第１電極層３ａおよび第１配向膜４ａが形成された第１配向処理基板１１ａと、第２基材２ｂ上に第２電極層３ｂおよび第２配向膜４ｂが形成された第２配向処理基板１１ｂと、第１配向膜４ａおよび第２配向膜４ｂの間に形成され、強誘電性液晶組成物を含む液晶層５とを有している。第１配向膜４ａおよび第２配向膜４ｂはいずれもラビング処理された膜であり、ラビング処理方向Ｄ１，Ｄ２がパラレルとなるように配置されている。液晶層５に含まれる強誘電性液晶組成物は、上記式（１）で表されるキラル化合物Ａおよび上記式（２）で表されるキラル化合物Ｂの少なくともいずれかのキラル化合物を含有している。 The liquid crystal display element of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view showing an example of the liquid crystal display element of the present invention. As illustrated in FIG. 1, the liquid crystal display element 1 includes a first alignment treatment substrate 11a in which a first electrode layer 3a and a first alignment film 4a are formed on a first substrate 2a, and a second substrate 2b. A liquid crystal containing a ferroelectric liquid crystal composition is formed between the second alignment substrate 11b on which the second electrode layer 3b and the second alignment film 4b are formed, and the first alignment film 4a and the second alignment film 4b. Layer 5. The first alignment film 4a and the second alignment film 4b are both rubbed films and are arranged so that the rubbing directions D1 and D2 are parallel. The ferroelectric liquid crystal composition contained in the liquid crystal layer 5 contains at least one chiral compound of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2). Yes.
　ここで、従来、強誘電性液晶組成物としては、相系列がスメクチックＡ相を経由してカライルスメクチックＣ相に至る、双安定性を示す強誘電性液晶組成物が知られている。このような双安定性を示す強誘電性液晶組成物は、図２に例示するように、一つのスメクチック層構造を有し、層法線ｚに対して二つの安定状態２５ａ、２５ｂを有している。この場合、正または負の極性の電圧を印加して液晶分子２５の自発分極の向きを揃えることで、２５ａ、２５ｂの２種類の安定状態をとることができる。 Here, heretofore, as a ferroelectric liquid crystal composition, a ferroelectric liquid crystal composition exhibiting bistability in which a phase series reaches a Kaille smectic C phase via a smectic A phase is known. As shown in FIG. 2, the ferroelectric liquid crystal composition exhibiting such bistability has one smectic layer structure and two stable states 25a and 25b with respect to the layer normal z. ing. In this case, two kinds of stable states 25a and 25b can be achieved by applying a positive or negative polarity voltage to align the direction of spontaneous polarization of the liquid crystal molecules 25.
　上記の双安定性を示す強誘電性液晶組成物を、ラビング配向膜がパラレルに配置された液晶セルに注入すると、図３に例示するようなシェブロン構造と呼ばれる、くの字に折れ曲がった構造が形成され、また折れ曲がりの方向が異なる二つの状態をとることが知られている。この場合、これらの二つの異なる状態の境界部分で欠陥が発生し、コントラストを低下させる原因となる。 When the ferroelectric liquid crystal composition exhibiting the above bistability is injected into a liquid crystal cell in which a rubbing alignment film is arranged in parallel, a structure called a chevron structure illustrated in FIG. It is known that two states are formed and the directions of bending are different. In this case, a defect occurs at the boundary between these two different states, causing a decrease in contrast.
　このような欠陥の発生を抑制するため、図４に例示するように、ラビング処理方向Ｄ１、Ｄ２をアンチパラレルにすることで、ブックシェルフ構造を形成させる方法が試みられているが、均一な配向状態を得るには、ラビング配向膜による液晶分子のプレチルト角を非常に大きくする必要がある等の課題も残っている。 In order to suppress the occurrence of such defects, as illustrated in FIG. 4, a method of forming a bookshelf structure by making the rubbing treatment directions D1 and D2 anti-parallel has been attempted. In order to obtain the state, there still remains a problem that it is necessary to greatly increase the pretilt angle of the liquid crystal molecules by the rubbing alignment film.
　また、強誘電性液晶組成物としては、相系列がスメクチックＡ相を経由せずにカイラルスメクチックＣ相に至る、単安定性を示し、かつハーフＶ字型スイッチング特性を有する強誘電性液晶組成物が知られている。このような強誘電性液晶組成物の場合、カイラルスメクチックＣ相への相転移と同時にスメクチック層構造を形成するので、図５に例示するように層法線ｚがラビング処理方向ｄに対して傾いた方向に形成される。この場合、図５に例示するように層法線ｚの方向が異なる二つのドメインが発生し、二つのドメインでは正負それぞれ逆極性の電圧にのみ液晶分子２５が動作するため、このままでは表示素子として使用できない。 In addition, as the ferroelectric liquid crystal composition, a ferroelectric liquid crystal composition exhibiting monostability in which the phase series reaches the chiral smectic C phase without passing through the smectic A phase and has a half V-shaped switching characteristic. It has been known. In the case of such a ferroelectric liquid crystal composition, since the smectic layer structure is formed simultaneously with the phase transition to the chiral smectic C phase, the layer normal z is inclined with respect to the rubbing treatment direction d as illustrated in FIG. It is formed in the direction. In this case, as illustrated in FIG. 5, two domains having different layer normal z directions are generated. In the two domains, the liquid crystal molecules 25 operate only with positive and negative voltages of opposite polarities. I can not use it.
　本発明における強誘電性液晶組成物は、上記式（１）で表されるキラル化合物Ａおよび上記式（２）で表されるキラル化合物Ｂの少なくともいずれかのキラル化合物を含有するものである。また、本発明における強誘電性液晶組成物も単安定性を示すものである。
　本発明者らは、このような強誘電性液晶組成物を用いて、種々のラビング配向膜の組合せおよびラビング処理方法における、電圧無印加時の液晶分子の安定位置と、電圧印加時の液晶分子の動作挙動を解析した結果、以下のことを見出した。 The ferroelectric liquid crystal composition in the present invention contains at least one of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2). The ferroelectric liquid crystal composition in the present invention also exhibits monostability.
The present inventors have used such a ferroelectric liquid crystal composition, and in various rubbing alignment film combinations and rubbing treatment methods, stable positions of liquid crystal molecules when no voltage is applied, and liquid crystal molecules when a voltage is applied As a result of analyzing the behavior of the following, we found the following.
　本発明における強誘電性液晶組成物を用いた液晶表示素子を平面視した図の一例を図６（ａ）、（ｂ）に示す。図６（ａ）、（ｂ）に例示するように、電圧無印加時にラビング処理方向ｄに対して液晶分子２５が安定する方向は２種類ある。図６（ａ）では、負の極性の電圧を印加したときに液晶分子２５が左方向に動き、正の極性の電圧を印加したときには液晶分子２５が右方向に動く。また、負の極性の電圧を印加したときの液晶分子２５の動作角の方が大きい。これに対して、図６（ｂ）では、図６（ａ）の場合と比較して、正負それぞれの極性に対する液晶分子２５の動作方向は同様であるが、動作角は反対に、負の極性の電圧を印加したときに小さく、正の極性の電圧を印加したときに大きい。いずれの場合も、正負それぞれの電圧を印加したときの位置は、それぞれ一致している。
　このような液晶分子の動作は、上述したような従来の、単安定性を示し、かつハーフＶ字型スイッチング特性を有する強誘電性液晶組成物とは異なっている。 An example of a plan view of a liquid crystal display element using the ferroelectric liquid crystal composition of the present invention is shown in FIGS. 6 (a) and 6 (b). As illustrated in FIGS. 6A and 6B, there are two types of directions in which the liquid crystal molecules 25 are stabilized with respect to the rubbing treatment direction d when no voltage is applied. In FIG. 6A, the liquid crystal molecules 25 move to the left when a negative polarity voltage is applied, and the liquid crystal molecules 25 move to the right when a positive polarity voltage is applied. Further, the operating angle of the liquid crystal molecules 25 when a negative polarity voltage is applied is larger. On the other hand, in FIG. 6B, compared with the case of FIG. 6A, the operation directions of the liquid crystal molecules 25 with respect to the positive and negative polarities are the same, but the operation angle is opposite and the negative polarity is obtained. Is small when a positive voltage is applied, and is large when a positive polarity voltage is applied. In either case, the positions when positive and negative voltages are applied coincide with each other.
The operation of such liquid crystal molecules is different from the conventional ferroelectric liquid crystal composition that exhibits monostability and has half V-shaped switching characteristics as described above.
　さらに、本発明における強誘電性液晶組成物を用いて、種々のラビング配向膜を使用し、パラレルまたはアンチパラレルとなるように配置して液晶表示素子を作製し、解析した。その結果、ラビング配向膜をパラレルとなるように配置した場合には、二つのドメインが発生した場合でも、いずれのドメインも、図６（ａ）または図６（ｂ）のいずれかに統一されていることがわかった。これに対して、ラビング配向膜をアンチパラレルとなるように配置した場合には、ほとんどのラビング配向膜の組合せで、二つのドメインが発生し、しかも図６（ａ）、（ｂ）の両方になっていた。 Furthermore, using the ferroelectric liquid crystal composition according to the present invention, various rubbing alignment films were used and arranged in parallel or anti-parallel to produce a liquid crystal display element and analyzed. As a result, when the rubbing alignment films are arranged in parallel, even when two domains are generated, both domains are unified into either FIG. 6 (a) or FIG. 6 (b). I found out. On the other hand, when the rubbing alignment film is arranged so as to be anti-parallel, two domains are generated in most combinations of rubbing alignment films, and in both FIGS. 6 (a) and 6 (b). It was.
　本発明における強誘電性液晶組成物を用いた液晶表示素子を断面から見た図を図７（ａ）、（ｂ）に示す。
　図７（ａ）に例示するようにラビング処理方向Ｄ１、Ｄ２がパラレルである場合は、（i）、（iii）に示すように液晶層に接する上下のラビング配向膜のそれぞれの影響を強く受けたドメインでは液晶分子２５のプレチルト角は異なるものの、（ii）、（iv）に示すように平面視における電圧無印加時の液晶分子２５の安定位置はほぼ一致している。そのため、ラビング配向膜による液晶分子のプレチルト角を小さくすることで、二つのドメインの差が小さくなるので、容易にモノドメインに揃えることができる。
　これに対して、図７（ｂ）に例示するようにラビング処理方向Ｄ１、Ｄ２がアンチパラレルである場合には、（v）、（viii）に示すように液晶層に接する上下のラビング配向膜のそれぞれの影響を強く受けたドメインでは液晶分子２５のプレチルト方向は同じであっても、（vii）、（x）に示すように平面視における電圧無印加時の液晶分子２５の安定状態の方向が大きく異なる。そのため、ラビング配向膜における液晶分子のプレチルト角をいかに制御しても、モノドメインにすることはできない。 FIGS. 7A and 7B show a cross-sectional view of a liquid crystal display element using the ferroelectric liquid crystal composition in the present invention.
When the rubbing treatment directions D1 and D2 are parallel as illustrated in FIG. 7A, each of the upper and lower rubbing alignment films in contact with the liquid crystal layer is strongly influenced as shown in (i) and (iii). Although the pretilt angles of the liquid crystal molecules 25 are different in the domain, as shown in (ii) and (iv), the stable positions of the liquid crystal molecules 25 when no voltage is applied in plan view are substantially the same. Therefore, by reducing the pretilt angle of the liquid crystal molecules by the rubbing alignment film, the difference between the two domains is reduced, so that the monodomain can be easily aligned.
On the other hand, when the rubbing directions D1 and D2 are anti-parallel as illustrated in FIG. 7B, the upper and lower rubbing alignment films in contact with the liquid crystal layer as shown in (v) and (viii) Even if the pretilt direction of the liquid crystal molecules 25 is the same in the domains strongly influenced by each of the above, the direction of the stable state of the liquid crystal molecules 25 when no voltage is applied in plan view as shown in (vii) and (x) Are very different. Therefore, no matter how the pretilt angle of the liquid crystal molecules in the rubbing alignment film is controlled, it cannot be a mono domain.
　このように本発明においては、上記式（１）で表されるキラル化合物Ａおよび上記式（２）で表されるキラル化合物Ｂの少なくともいずれかのキラル化合物を含有し、耐衝撃性を発揮し得る強誘電性液晶組成物を用いた場合に、第１配向膜および第２配向膜がラビング処理方向がパラレルとなるように配置されていることにより、平面視での電圧無印加時の液晶分子の安定位置を揃えることができ、さらにはモノドメイン配向を得ることが可能であり、表示品質に優れた液晶表示素子とすることが可能である。 As described above, the present invention contains at least one of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2) and exhibits impact resistance. When the ferroelectric liquid crystal composition to be obtained is used, the first alignment film and the second alignment film are arranged so that the rubbing treatment directions are parallel, so that liquid crystal molecules when no voltage is applied in plan view These liquid crystal display elements can be provided with excellent display quality.
　以下、本発明の液晶表示素子における各構成について説明する。 Hereinafter, each configuration of the liquid crystal display element of the present invention will be described.
　Ａ．第１配向膜および第２配向膜
　本発明において、第１配向膜および第２配向膜はラビング処理された膜であり、ラビング処理方向がパラレルとなるように配置されているものである。 A. 1st alignment film and 2nd alignment film In this invention, a 1st alignment film and a 2nd alignment film are films | membranes which were rubbed, and are arrange | positioned so that the rubbing process direction may become parallel.
　ここで、第１配向膜および第２配向膜はラビング処理方向がパラレルとなるように配置されているとは、第１配向膜のラビング処理方向と第２配向膜のラビング処理方向とが平行かつ同一方向であることをいう。
　第１配向膜のラビング処理方向と第２配向膜のラビング処理方向とが平行であるとは、第１配向膜のラビング処理方向と第２配向膜のラビング処理方向とのなす角度が０±５度の範囲内であることをいう。 Here, the first alignment film and the second alignment film are arranged so that the rubbing treatment directions are parallel, that the rubbing treatment direction of the first alignment film and the rubbing treatment direction of the second alignment film are parallel and The same direction.
That the rubbing treatment direction of the first alignment film and the rubbing treatment direction of the second alignment film are parallel means that the angle formed by the rubbing treatment direction of the first alignment film and the rubbing treatment direction of the second alignment film is 0 ± 5. It is within the range of degrees.
　なお、第１配向膜および第２配向膜がラビング処理方向がパラレルとなるように配置されていることは、第１配向膜および第２配向膜に対する液晶分子のプレチルト角を測定することにより確認することができる。液晶分子のプレチルトの方向により、ラビング処理を施した方向を判別することが可能である。
　また、プレチルト角は、クリスタルローテンション法により測定することができる。 In addition, it is confirmed by measuring the pretilt angle of the liquid crystal molecules with respect to the first alignment film and the second alignment film that the first alignment film and the second alignment film are arranged so that the rubbing treatment directions are parallel. be able to. The direction in which the rubbing process is performed can be determined from the pretilt direction of the liquid crystal molecules.
The pretilt angle can be measured by a crystal rotation method.
　第１配向膜および第２配向膜に対する液晶分子のプレチルト角としては、特に限定されるものではないが、表示品質および耐衝撃性の観点から、１０度以下であることが好ましく、より好ましくは５度以下、さらに好ましくは３度以下である。上述したように、第１配向膜および第２配向膜に対する液晶分子のプレチルト角を小さくすることで、二つのドメインの差が小さくなるので、容易にモノドメインに揃えることができるからである。また、プレチルト角が小さいほうが、衝撃が加わったときの液晶分子の傾斜角の変化が少なく、元の状態に戻りやすいためであると推量される。
　プレチルト角は小さいほど好ましいことから、プレチルト角の下限は特に限定されないが、通常は１度程度である。
　プレチルト角は、第１配向膜および第２配向膜の材料や、ラビング処理の条件等により適宜調整することが可能である。 The pretilt angle of the liquid crystal molecules with respect to the first alignment film and the second alignment film is not particularly limited, but is preferably 10 degrees or less, more preferably 5 from the viewpoint of display quality and impact resistance. Degrees or less, more preferably 3 degrees or less. As described above, by reducing the pretilt angle of the liquid crystal molecules with respect to the first alignment film and the second alignment film, the difference between the two domains is reduced, so that the monodomain can be easily aligned. Also, it is presumed that the smaller the pretilt angle, the smaller the change in the tilt angle of the liquid crystal molecules when an impact is applied, and the easier it is to return to the original state.
Since the pretilt angle is preferably as small as possible, the lower limit of the pretilt angle is not particularly limited, but is usually about 1 degree.
The pretilt angle can be appropriately adjusted depending on the materials of the first alignment film and the second alignment film, the conditions of the rubbing treatment, and the like.
　第１配向膜および第２配向膜に用いられる材料としては、ラビング処理により膜に異方性を付与することができるものであれば特に限定されるものではなく、例えば、ナイロン、ポリイミド、ポリアミド、ポリアミック酸、ポリアミドイミド、ポリエーテルイミド、ポリビニルアルコール、ポリウレタン等を挙げることができる。これらは、単独で用いてもよく２種以上を組み合わせて用いてもよい。 The material used for the first alignment film and the second alignment film is not particularly limited as long as anisotropy can be imparted to the film by rubbing treatment. For example, nylon, polyimide, polyamide, Examples thereof include polyamic acid, polyamideimide, polyetherimide, polyvinyl alcohol, and polyurethane. These may be used alone or in combination of two or more.
　中でも、第１配向膜および第２配向膜がポリイミドを含有することが好ましい。ポリイミドを含有する第１配向膜および第２配向膜では、液晶分子が方位角方向に配向しやすくなるからである。すなわち、液晶分子が一定方向に配列しやすくなるのである。 Among these, it is preferable that the first alignment film and the second alignment film contain polyimide. This is because the liquid crystal molecules are easily aligned in the azimuth direction in the first alignment film and the second alignment film containing polyimide. That is, the liquid crystal molecules are easily arranged in a certain direction.
　第１配向膜および第２配向膜に用いられるポリイミドは、プレチルト角を上記範囲とするものであることが好ましい。
　プレチルト角を上記範囲とするには、例えば、ポリイミドの側鎖の長さを短くすることが好ましい。高分子の側鎖の鎖長を変化させることによりプレチルト角を制御する方法が知られており、側鎖の長さが増加するとプレチルト角が増加することが報告されている。
　また、プレチルト角を上記範囲とするには、例えば、ポリイミドの側鎖の密度を小さくすることが好ましい。 The polyimide used for the first alignment film and the second alignment film preferably has a pretilt angle in the above range.
In order to make the pretilt angle within the above range, for example, it is preferable to shorten the length of the polyimide side chain. A method of controlling the pretilt angle by changing the chain length of the polymer side chain is known, and it has been reported that the pretilt angle increases as the side chain length increases.
In order to set the pretilt angle within the above range, for example, it is preferable to reduce the density of the side chain of the polyimide.
　ラビング処理方法としては、一般的な方法を適用することができる。
　なお、ラビング処理におけるローラーの押し込み量、回転数、速度や、ラビング処理の回数等を調整することにより、プレチルト角を制御することができる。プレチルト角を上記範囲とするには、例えば、押し込み量を少なくすることが好ましい。 As the rubbing treatment method, a general method can be applied.
It should be noted that the pretilt angle can be controlled by adjusting the amount of roller pressing, the number of rotations, the speed, the number of rubbing processes, and the like in the rubbing process. In order to set the pretilt angle within the above range, for example, it is preferable to reduce the push-in amount.
　第１配向膜および第２配向膜の厚みは、１ｎｍ～１０００ｎｍ程度で設定され、好ましくは５０ｎｍ～１００ｎｍの範囲内である。 The thickness of the first alignment film and the second alignment film is set to about 1 nm to 1000 nm, and preferably in the range of 50 nm to 100 nm.
　本発明においては、第１配向膜の構成材料および第２配向膜の構成材料が液晶層を挟んで互いに異なる組成を有することが好ましい。このような構成とすることにより、液晶分子の自発分極の向きを揃えることができ、モノドメイン化することができるからである。また、配向欠陥の発生を抑制し、コントラストを向上させることができるからである。 In the present invention, the constituent material of the first alignment film and the constituent material of the second alignment film preferably have different compositions across the liquid crystal layer. This is because by adopting such a configuration, the direction of spontaneous polarization of liquid crystal molecules can be made uniform, and a monodomain can be formed. Moreover, it is because generation | occurrence | production of orientation defect can be suppressed and contrast can be improved.
　第１配向膜の構成材料および第２配向膜の構成材料が液晶層を挟んで互いに異なる組成を有する場合、第１配向膜と第２配向膜とでは、強誘電性液晶組成物と第１配向膜表面および第２配向膜表面との相互作用である、極性表面相互作用が異なると考えられる。そのため、第１配向膜と第２配向膜とで、第２配向膜の方が相対的に正の極性が強い傾向にある場合には、電圧無印加状態において、図８に例示するように、極性表面相互作用によって、液晶分子２５の自発分極Ｐｓの正の極性が第１配向膜４ａ側を向くと考えられる。一方、第１配向膜と第２配向膜とで、第１配向膜の方が相対的に正の極性が強い傾向にある場合には、電圧無印加状態において、図９に例示するように、極性表面相互作用によって、液晶分子２５の自発分極Ｐｓの正の極性が第２配向膜４ｂ側を向くと考えられる。自発分極の向きがこのような方向になるのは、自発分極の向きが、液晶分子の分極と配向膜の分極とが電気的につり合う方向になり、液晶分子が電気的に安定な状態になるためであると思料される。なお、図８および図９において、液晶層については液晶分子を示している。 When the constituent material of the first alignment film and the constituent material of the second alignment film have different compositions across the liquid crystal layer, the ferroelectric liquid crystal composition and the first alignment are used in the first alignment film and the second alignment film. It is considered that the polar surface interaction, which is the interaction between the film surface and the second alignment film surface, is different. Therefore, in the first alignment film and the second alignment film, when the second alignment film tends to have a relatively positive polarity, as illustrated in FIG. It is considered that the positive polarity of the spontaneous polarization Ps of the liquid crystal molecules 25 faces the first alignment film 4a side due to the polar surface interaction. On the other hand, in the first alignment film and the second alignment film, when the first alignment film tends to have a relatively positive polarity, as illustrated in FIG. It is considered that the positive polarity of the spontaneous polarization Ps of the liquid crystal molecules 25 faces the second alignment film 4b side due to the polar surface interaction. The direction of spontaneous polarization is such a direction because the direction of spontaneous polarization is the direction in which the polarization of the liquid crystal molecules and the alignment film are electrically balanced, and the liquid crystal molecules are in an electrically stable state. It seems to be because. 8 and 9, the liquid crystal layer shows liquid crystal molecules.
　したがって、第１配向膜および第２配向膜を互いに異なる組成を有する材料を用いて形成することにより、それぞれの材料に応じて第１配向膜表面および第２配向膜表面の極性を異ならせることができる。これにより、強誘電性液晶組成物および第１配向膜の極性表面相互作用と、強誘電性液晶組成物および第２配向膜の極性表面相互作用とが異なるものとなるため、第１配向膜および第２配向膜の表面極性を考慮して材料を適宜選択することによって、自発分極の向きを制御することができる。その結果、強誘電性液晶組成物に特有の配向欠陥の発生を抑制することができ、コントラストを向上させることが可能となる。さらには、モノドメイン配向を得ることが可能となる。 Therefore, by forming the first alignment film and the second alignment film using materials having different compositions, the polarities of the first alignment film surface and the second alignment film surface can be made different depending on the respective materials. it can. As a result, the polar surface interaction between the ferroelectric liquid crystal composition and the first alignment film is different from the polar surface interaction between the ferroelectric liquid crystal composition and the second alignment film. The direction of spontaneous polarization can be controlled by appropriately selecting a material in consideration of the surface polarity of the second alignment film. As a result, the occurrence of alignment defects peculiar to the ferroelectric liquid crystal composition can be suppressed, and the contrast can be improved. Furthermore, a monodomain orientation can be obtained.
　第１配向膜および第２配向膜の構成材料の組成を異ならせる手法としては、例えば、一方にポリイミドを用い、他方にナイロンを用いるなど、材料系の種類を異ならせる方法、側鎖の異なるポリイミドを用いるなど、側鎖を異ならせる方法、添加剤の含有量を変える、添加剤の有無など、各成分の含有量を異ならせる方法等が挙げられる。 As a method of making the composition of the constituent materials of the first alignment film and the second alignment film different, for example, a method of different types of material systems such as using polyimide on one side and nylon on the other side, polyimides having different side chains And the like, a method of varying the side chain, a method of changing the content of the additive, and a method of varying the content of each component such as the presence or absence of the additive.
　Ｂ．液晶層
　本発明における液晶層は、第１配向処理基板の第１配向膜および第２配向処理基板の第２配向膜の間に形成され、強誘電性液晶組成物を含むものである。
　以下、液晶層における各構成について説明する。 B. Liquid Crystal Layer The liquid crystal layer in the present invention is formed between the first alignment film of the first alignment treatment substrate and the second alignment film of the second alignment treatment substrate, and includes a ferroelectric liquid crystal composition.
Hereinafter, each configuration in the liquid crystal layer will be described.
　１．強誘電性液晶組成物
　本発明に用いられる強誘電性液晶組成物は、上記式（１）で表されるキラル化合物Ａおよび上記式（２）で表されるキラル化合物Ｂの少なくともいずれかのキラル化合物を含有するものである。
　以下、強誘電性液晶組成物における各成分について説明する。 1. Ferroelectric liquid crystal composition The ferroelectric liquid crystal composition used in the present invention is a chiral compound of at least one of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2). It contains a compound.
Hereinafter, each component in the ferroelectric liquid crystal composition will be described.
　（１）キラル化合物
　本発明に用いられるキラル化合物は、上記式（１）で表されるキラル化合物Ａおよび上記式（２）で表されるキラル化合物Ｂの少なくともいずれかのキラル化合物である。 (1) Chiral compound The chiral compound used in the present invention is at least one of the chiral compound A represented by the above formula (1) and the chiral compound B represented by the above formula (2).
　本発明において、強誘電性液晶組成物は、キラル化合物Ａおよびキラル化合物Ｂの少なくともいずれかを含有していればよく、例えば、キラル化合物Ａのみを含有していてもよく、キラル化合物Ｂのみを含有していてもよく、キラル化合物Ａおよびキラル化合物Ｂを含有していてもよい。また、強誘電性液晶組成物がキラル化合物Ａを含有する場合、１種類のキラル化合物Ａを含有していてもよく、２種類以上のキラル化合物Ａを含有していてもよい。同様に、強誘電性液晶組成物がキラル化合物Ｂを含有する場合、１種類のキラル化合物Ｂを含有していてもよく、２種類以上のキラル化合物Ｂを含有していてもよい。 In the present invention, the ferroelectric liquid crystal composition only needs to contain at least one of the chiral compound A and the chiral compound B. For example, the ferroelectric liquid crystal composition may contain only the chiral compound A or only the chiral compound B. It may contain, and the chiral compound A and the chiral compound B may be contained. Further, when the ferroelectric liquid crystal composition contains the chiral compound A, it may contain one kind of chiral compound A or two or more kinds of chiral compounds A. Similarly, when the ferroelectric liquid crystal composition contains the chiral compound B, it may contain one kind of chiral compound B or may contain two or more kinds of chiral compounds B.
　以下、キラル化合物Ａおよびキラル化合物Ｂに分けて説明する。 Hereinafter, the description will be divided into chiral compound A and chiral compound B.
　（ａ）キラル化合物Ａ
　本発明に用いられるキラル化合物Ａは、下記一般式（１）で表される。 (A) Chiral compound A
The chiral compound A used in the present invention is represented by the following general formula (1).
Figure JPOXMLDOC01-appb-C000007
Figure JPOXMLDOC01-appb-C000007
（上記式（１）において、Ｒ1は、非キラルな基であり、ハロゲン原子で置換されていてもよい炭素数４～１８の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
Ｒ２は、キラルな基であり、下記一般式（３）で表される基である。 (In the above formula (1), R 1 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
R 2 is a chiral group and is a group represented by the following general formula (3).
Figure JPOXMLDOC01-appb-C000008
Figure JPOXMLDOC01-appb-C000008
（上記式（３）において、Ｒ３は、ハロゲン原子で置換されていてもよい炭素数１～１０の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
Ｙ１は、－ＣＨ３またはフッ素原子を表す。ｍは０または１である。ｎは０または１である。＊印はキラル中心を示す。）
Ｘ１～Ｘ８は、それぞれ独立して－ＣＨ３、－ＣＦ３、ハロゲン原子または水素原子を表す。ただし、Ｘ１～Ｘ８のうち１つ以上は、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子である。） (In the above formula (3), R 3 is a saturated or unsaturated alkyl or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
Y 1 represents —CH 3 or a fluorine atom. m is 0 or 1. n is 0 or 1. * Indicates a chiral center. )
X 1 to X 8 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 1 to X 8 are each independently —CH 3 , —CF 3 or a halogen atom. )
　上記式（１）において、Ｒ1は、非キラルな基であり、ハロゲン原子で置換されていてもよい炭素数４～１８の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
　炭素数は４～１８であればよいが、中でも６～１８が好ましく、６～１２がさらに好ましい。炭素数が上記範囲よりも多いと、キラル化合物Ａの合成が困難となり、コストが嵩むからである。一方、炭素数が上記範囲よりも少ないと、強誘電性液晶組成物がスメクチック相を発現しない場合があるからである。なお、アルキル基およびアルコシキアルキル基がハロゲン原子で置換されている場合には、炭素数が比較的少なくとも、強誘電性液晶組成物がスメクチック相を発現する場合がある。
　アルキル基またはアルコシキアルキル基は、ハロゲン原子で置換されていてもよく、ハロゲン原子で置換されていなくてもよいが、中でも、ハロゲン原子で置換されていないことが好ましい。
　アルキル基またはアルコキシアルキル基は、直鎖状または分岐状である。
　アルキル基またはアルコシキアルキル基は、飽和であっても不飽和であってもよいが、中でも飽和であることが好ましい。環状の不飽和アルカン以外の不飽和アルカンにおいては、不飽和アルカンは飽和アルカンに比べて反応性が高く、長期の保存・駆動や温度変化により材質が変化し、表示品質が劣化するおそれがあるからである。
　Ｒ1はアルキル基であってもアルコキシアルキル基であってもよいが、中でもアルキル基であることが好ましい。 In the above formula (1), R 1 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
The number of carbon atoms may be 4 to 18, but 6 to 18 is preferable and 6 to 12 is more preferable. This is because when the number of carbon atoms is larger than the above range, the synthesis of the chiral compound A becomes difficult and the cost increases. On the other hand, if the number of carbon atoms is less than the above range, the ferroelectric liquid crystal composition may not exhibit a smectic phase. In addition, when the alkyl group and the alkoxyalkyl group are substituted with a halogen atom, the ferroelectric liquid crystal composition may exhibit a smectic phase with a relatively small number of carbon atoms.
The alkyl group or alkoxyalkyl group may be substituted with a halogen atom or may not be substituted with a halogen atom, but is preferably not substituted with a halogen atom.
The alkyl group or alkoxyalkyl group is linear or branched.
The alkyl group or alkoxyalkyl group may be saturated or unsaturated, but is preferably saturated. In unsaturated alkanes other than cyclic unsaturated alkanes, unsaturated alkanes are more reactive than saturated alkanes, and the display quality may be deteriorated due to changes in materials due to long-term storage / driving and temperature changes. It is.
R 1 may be an alkyl group or an alkoxyalkyl group, but is preferably an alkyl group.
　上記式（１）において、Ｒ２は、１個以上のキラル中心をもつキラルな基であり、上記式（３）で表される基である。 In the above formula (1), R 2 is a chiral group having one or more chiral centers, and is a group represented by the above formula (3).
　上記式（３）において、Ｒ３は、ハロゲン原子で置換されていてもよい炭素数１～１０の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
　アルキル基またはアルコキシアルキル基は、直鎖状、分岐状または環状である。
　Ｒ３はアルキル基であってもアルコキシアルキル基であってもよいが、中でもアルキル基であることが好ましい。 In the above formula (3), R 3 is a saturated or unsaturated alkyl group or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
The alkyl group or alkoxyalkyl group is linear, branched or cyclic.
R 3 may be an alkyl group or an alkoxyalkyl group, but is preferably an alkyl group.
　上記式（３）において、Ｙ１は、－ＣＨ３またはフッ素原子を表す。－ＣＨ３の場合には、キラル化合物Ａの合成が容易であるという利点を有する。一方、フッ素原子の場合、液晶分子の自発分極の大きさを大きくすることができ、応答速度を速くすることができるという利点もある。
　Ｙ１は－ＣＨ３であってもフッ素原子であってもよいが、中でも－ＣＨ３であることが好ましい。上述したようにキラル化合物Ａの合成が容易であり、安定してキラル化合物Ａを製造することができ、強誘電性液晶組成物を安価に得ることができるからである。 In the above formula (3), Y 1 represents —CH 3 or a fluorine atom. In the case of —CH 3 , there is an advantage that the synthesis of the chiral compound A is easy. On the other hand, in the case of fluorine atoms, there is an advantage that the magnitude of the spontaneous polarization of the liquid crystal molecules can be increased and the response speed can be increased.
Y 1 may be —CH 3 or a fluorine atom, and among them, —CH 3 is preferable. As described above, the synthesis of the chiral compound A is easy, the chiral compound A can be produced stably, and the ferroelectric liquid crystal composition can be obtained at a low cost.
　上記式（３）において、ｍは０または１である。
　また、上記式（３）において、＊印はキラル中心を示す。ｍ＝０のとき、１位の炭素原子がキラル中心となり、ｍ＝１のとき、２位の炭素原子がキラル中心となる。 In the above formula (3), m is 0 or 1.
In the above formula (3), * indicates a chiral center. When m = 0, the 1st carbon atom becomes a chiral center, and when m = 1, the 2nd carbon atom becomes a chiral center.
　上記式（３）において、ｎは０または１である。 In the above formula (3), n is 0 or 1.
　上記式（１）において、Ｘ１～Ｘ８は、それぞれ独立して－ＣＨ３、－ＣＦ３、ハロゲン原子または水素原子を表す。ただし、Ｘ１～Ｘ８のうち１つ以上は、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子である。
　Ｘ１～Ｘ８のすべてが水素原子である場合には、キラル化合物Ａの溶解性が低下するため、キラル化合物Ａの合成、精製が困難になり、コストが高くなったり、また強誘電性液晶組成物が結晶化しやすいものとなり、所望の耐衝撃性が得られなかったりするおそれがある。これに対し、本発明のようにＸ１～Ｘ８のうち１つ以上が－ＣＨ３、－ＣＦ３またはハロゲン原子である場合には、キラル化合物Ａの溶媒への溶解性が高くなり、大量合成、精製が可能になる。また、キラル化合物Ａの立体構造に歪みが生じ、この歪みによって強誘電性液晶組成物の結晶化が阻害されるので、高い耐衝撃性を得ることができると考えられる。 In the above formula (1), X 1 to X 8 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 1 to X 8 are each independently —CH 3 , —CF 3 or a halogen atom.
When all of X 1 to X 8 are hydrogen atoms, the solubility of the chiral compound A decreases, so that the synthesis and purification of the chiral compound A becomes difficult, the cost increases, and the ferroelectric liquid crystal The composition is easily crystallized, and the desired impact resistance may not be obtained. On the other hand, when one or more of X 1 to X 8 is —CH 3 , —CF 3 or a halogen atom as in the present invention, the solubility of the chiral compound A in the solvent is increased, and a large amount Synthesis and purification become possible. Further, since the steric structure of the chiral compound A is distorted and the crystallization of the ferroelectric liquid crystal composition is hindered by this distortion, it is considered that high impact resistance can be obtained.
　中でも、Ｘ１～Ｘ３、Ｘ５～Ｘ７のいずれか１つ以上が、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子であることが好ましい。Ｘ１～Ｘ３、Ｘ５～Ｘ７の位置に置換基を有する場合はＸ４、Ｘ８の位置の場合よりもキラル化合物の溶解性が良いからである。これは、Ｘ４、Ｘ８の位置の場合は他の位置の場合に比べて置換基による歪みが少ないためであると考えられる。 Among these, any one or more of X 1 to X 3 and X 5 to X 7 are preferably each independently —CH 3 , —CF 3 or a halogen atom. This is because the chiral compound has better solubility than the X 4 and X 8 positions when it has a substituent at the X 1 to X 3 and X 5 to X 7 positions. This is presumably because the X 4 and X 8 positions are less distorted by substituents than the other positions.
　Ｘ１～Ｘ８が結合している２個のベンゼン環のうち、置換基を有するベンゼン環は、１～４個の置換基を有することができるが、中でも１個の置換基を有することが好ましい。すなわち、Ｘ１、Ｘ２、Ｘ５、Ｘ６が結合しているベンゼン環が置換基を有する場合には、Ｘ１、Ｘ２、Ｘ５、Ｘ６のうちいずれか１つが、－ＣＨ３、－ＣＦ３またはハロゲン原子であることが好ましい。またＸ３、Ｘ４、Ｘ７、Ｘ８が結合しているベンゼン環が置換基を有する場合には、Ｘ３、Ｘ４、Ｘ７、Ｘ８のうちいずれか１つが、－ＣＨ３、－ＣＦ３またはハロゲン原子であることが好ましい。
　特に、Ｘ１～Ｘ８のうちいずれか１つのみが、－ＣＨ３、－ＣＦ３またはハロゲン原子であることが好ましい。 Of the two benzene rings to which X 1 to X 8 are bonded, the benzene ring having a substituent can have 1 to 4 substituents, and among them, it can have one substituent. preferable. That is, when the benzene ring to which X 1 , X 2 , X 5 , and X 6 are bonded has a substituent, any one of X 1 , X 2 , X 5 , and X 6 is —CH 3 , —CF 3 or a halogen atom is preferable. When the benzene ring to which X 3 , X 4 , X 7 , X 8 is bonded has a substituent, any one of X 3 , X 4 , X 7 , X 8 is —CH 3 , It is preferably —CF 3 or a halogen atom.
In particular, it is preferable that only one of X 1 to X 8 is —CH 3 , —CF 3 or a halogen atom.
　また、置換基を有するベンゼン環が、２個の置換基を有することも好ましい。この場合、上記２個の置換基の位置としては、例えばＸ１およびＸ２がフッ素原子である場合のようにベンゼン環の隣り合う炭素原子にそれぞれフッ素原子が置換していることが好ましい。ベンゼン環の隣り合う炭素原子に２個のフッ素原子がそれぞれ置換し、ベンゼン環が対称的に置換されている場合には、カイラルスメクチックＣ相が安定し、液晶分子のチルト角を大きくすることができるため、液晶表示素子の透過率を高めることができる。また、２個の置換基がより近くに位置する炭素原子に結合していることにより、上記キラル化合物の棒状の構造を崩さないため、耐衝撃性を維持することができる。
　さらに、Ｘ１～Ｘ８が結合している２個のベンゼン環のうち、１個のベンゼン環が２個の置換基を有することが好ましく、中でも、Ｘ１、Ｘ２、Ｘ５、Ｘ６が結合しているベンゼン環が２個の置換基を有することが好ましい。直接結合された３個のベンゼン環のうち、真ん中に位置するベンゼン環が置換基を有することにより、強誘電性液晶組成物が結晶化しにくくなるからである。
　特に、Ｘ１およびＸ２、または、Ｘ５およびＸ６がフッ素原子であることが好ましい。 Moreover, it is also preferable that the benzene ring which has a substituent has two substituents. In this case, as the positions of the above two substituents, it is preferable that fluorine atoms are respectively substituted on adjacent carbon atoms of the benzene ring as in the case where, for example, X 1 and X 2 are fluorine atoms. When two fluorine atoms are substituted on adjacent carbon atoms of the benzene ring, and the benzene ring is symmetrically substituted, the chiral smectic C phase is stabilized and the tilt angle of the liquid crystal molecules can be increased. Therefore, the transmittance of the liquid crystal display element can be increased. Further, since the two substituents are bonded to a carbon atom located closer to each other, the rod-like structure of the chiral compound is not destroyed, so that the impact resistance can be maintained.
Furthermore, among the two benzene rings to which X 1 to X 8 are bonded, one benzene ring preferably has two substituents, and among them, X 1 , X 2 , X 5 , X 6 The benzene ring to which is bonded preferably has two substituents. This is because, among the three directly bonded benzene rings, the ferroelectric liquid crystal composition is difficult to crystallize because the middle benzene ring has a substituent.
In particular, X 1 and X 2 or X 5 and X 6 are preferably fluorine atoms.
　また、ベンゼン環が有する置換基は、置換基が１個の場合には－ＣＨ３、フッ素原子または塩素原子であることが好ましく、－ＣＨ３またはフッ素原子であることが特に好ましい。一方、置換基が２個の場合にはいずれの置換基もフッ素原子であることが好ましい。なお、ベンゼン環に２個のフッ素原子が置換している場合には、上記２個のフッ素原子は隣り合う炭素原子にそれぞれ置換していることが好ましい。 Further, the substituent that the benzene ring has is preferably —CH 3 , a fluorine atom, or a chlorine atom, and particularly preferably —CH 3 or a fluorine atom, when there is one substituent. On the other hand, when there are two substituents, it is preferable that any substituent is a fluorine atom. When two fluorine atoms are substituted on the benzene ring, the two fluorine atoms are preferably substituted with adjacent carbon atoms.
　上記式（１）で表されるキラル化合物Ａの具体例としては、下記一般式（１－１）～（１－２）および（１－３）～（１－４）で表されるキラル化合物Ａが挙げられる。 Specific examples of the chiral compound A represented by the above formula (1) include chiral compounds represented by the following general formulas (1-1) to (1-2) and (1-3) to (1-4) A is mentioned.
Figure JPOXMLDOC01-appb-C000009
Figure JPOXMLDOC01-appb-C000009
（上記式（１－１）～（１－２）および（１－３）～（１－４）において、Ｒ１１は炭素数１～１０の飽和または不飽和のアルキル基であり、＊印はキラル中心を示し、ｍは０または１であり、ｐは４～１８であり、Ｘ２１およびＸ２２はそれぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子を表し、上記式（１－１）～（１－２）におけるｊおよびｋは一方が０、他方が１である。） (In the above formulas (1-1) to (1-2) and (1-3) to (1-4), R 11 is a saturated or unsaturated alkyl group having 1 to 10 carbon atoms. Represents a chiral center, m is 0 or 1, p is 4 to 18, X 21 and X 22 each independently represent —CH 3 , —CF 3 or a halogen atom, and the above formula (1-1 ) To (1-2), one of j and k is 0 and the other is 1.)
　上記式（１－１）～（１－２）および（１－３）～（１－４）において、ｐは４～１８であり、好ましくは６～１８、より好ましくは６～１２である。上述したように、炭素数が上記範囲よりも多いと、キラル化合物Ａの合成が困難となるからである。一方、炭素数が上記範囲よりも少ないと、強誘電性液晶組成物がスメクチック相を発現しない場合があるからである。 In the above formulas (1-1) to (1-2) and (1-3) to (1-4), p is 4 to 18, preferably 6 to 18, and more preferably 6 to 12. As described above, when the number of carbon atoms is larger than the above range, the synthesis of the chiral compound A becomes difficult. On the other hand, if the number of carbon atoms is less than the above range, the ferroelectric liquid crystal composition may not exhibit a smectic phase.
　上記式（１－１）～（１－２）および（１－３）～（１－４）において、Ｒ１１は炭素数１～１０の飽和または不飽和のアルキル基である。アルキル基は、直鎖状、分岐状または環状である。中でも、Ｒ１１は、直鎖状もしくは分岐状の飽和のアルキル基、またはフェニルアルキル基であることが好ましい。 In the above formulas (1-1) to (1-2) and (1-3) to (1-4), R 11 is a saturated or unsaturated alkyl group having 1 to 10 carbon atoms. The alkyl group is linear, branched or cyclic. Among these, R 11 is preferably a linear or branched saturated alkyl group or a phenylalkyl group.
　上記式（１－２）および（１－４）において、ｍは０または１である。
　また、上記式（１－１）～（１－２）および（１－３）～（１－４）において、＊印はキラル中心を示す。上記式（１－１）および（１－３）では、１位の炭素原子がキラル中心となる。上記式（１－２）および（１－４）では、ｍ＝０のとき、１位の炭素原子がキラル中心となり、ｍ＝１のとき、２位の炭素原子がキラル中心となる。 In the above formulas (1-2) and (1-4), m is 0 or 1.
In the above formulas (1-1) to (1-2) and (1-3) to (1-4), * indicates a chiral center. In the above formulas (1-1) and (1-3), the carbon atom at the 1-position is a chiral center. In the above formulas (1-2) and (1-4), when m = 0, the 1-position carbon atom becomes a chiral center, and when m = 1, the 2-position carbon atom becomes a chiral center.
　上記式（１－１）～（１－２）において、Ｘ２１およびＸ２２は、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子を表す。中でも、－ＣＨ３、フッ素原子または塩素原子が好ましく、特に－ＣＨ３またはフッ素原子が好ましい。
　Ｘ２１およびＸ２２の位置としては、上述のＸ１～Ｘ８の位置と同様である。 In the above formulas (1-1) to (1-2), X 21 and X 22 each independently represent —CH 3 , —CF 3 or a halogen atom. Among them, —CH 3 , a fluorine atom or a chlorine atom is preferable, and —CH 3 or a fluorine atom is particularly preferable.
The positions of X 21 and X 22 are the same as the positions of X 1 to X 8 described above.
　また、上記式（１－１）および（１－２）において、ｊおよびｋは、一方が０、他方が１である。 In the above formulas (1-1) and (1-2), one of j and k is 0 and the other is 1.
　上記式（１－１）および（１－２）で表されるキラル化合物Ａの具体例としては、下記式で表されるキラル化合物Ａを挙げることができる。 Specific examples of the chiral compound A represented by the above formulas (1-1) and (1-2) include a chiral compound A represented by the following formula.
Figure JPOXMLDOC01-appb-C000010
Figure JPOXMLDOC01-appb-C000010
Figure JPOXMLDOC01-appb-C000011
Figure JPOXMLDOC01-appb-C000011
　また上記式（１－３）および（１－４）で表されるキラル化合物Ａの具体例としては、下記式で表されるキラル化合物Ａを挙げることができる。なお、右旋性を（＋）、左旋性を（－）で示す。 Further, specific examples of the chiral compound A represented by the above formulas (1-3) and (1-4) include a chiral compound A represented by the following formula. The dextrorotatory property is indicated by (+) and the levorotatory property is indicated by (−).
Figure JPOXMLDOC01-appb-C000012
Figure JPOXMLDOC01-appb-C000012
　このようなキラル化合物Ａとしては、１種を単独で用いてもよく、２種以上を混合して用いてもよい。 As such chiral compound A, one kind may be used alone, or two or more kinds may be mixed and used.
　強誘電性液晶組成物中のキラル化合物Ａの含有量としては、耐衝撃性の効果が得られる程度であれば特に限定されるものではない。上記キラル化合物Ａを１種単独で用いる場合にはそのキラル化合物Ａの含有量が、上記キラル化合物Ａを２種以上混合する場合には２種以上のキラル化合物Ａの各含有量が、強誘電性液晶組成物中にて５質量％以上であることが好ましい。 The content of the chiral compound A in the ferroelectric liquid crystal composition is not particularly limited as long as an impact resistance effect is obtained. When one of the above chiral compounds A is used alone, the content of the chiral compound A is ferroelectric. When two or more of the above chiral compounds A are mixed, each content of two or more of the chiral compounds A is ferroelectric. It is preferable that it is 5 mass% or more in a crystalline liquid crystal composition.
　キラル化合物Ａは、例えば、国際公開第２０１０／０３１４３１号パンフレットに記載の方法により合成することができる。 Chiral compound A can be synthesized, for example, by the method described in International Publication No. 2010/031431.
　（ｂ）キラル化合物Ｂ
　本発明に用いられるキラル化合物Ｂは、下記一般式（２）で表される。 (B) Chiral compound B
The chiral compound B used in the present invention is represented by the following general formula (2).
Figure JPOXMLDOC01-appb-C000013
Figure JPOXMLDOC01-appb-C000013
（上記式（２）において、Ｒ４は、非キラルな基であり、ハロゲン原子で置換されていてもよい炭素数４～１８の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
Ｒ５は、キラルな基であり、下記式（３）で表される基である。 (In the above formula (2), R 4 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
R 5 is a chiral group and is a group represented by the following formula (3).
Figure JPOXMLDOC01-appb-C000014
Figure JPOXMLDOC01-appb-C000014
（上記式（３）において、Ｒ３は、ハロゲン原子で置換されていてもよい炭素数１～１０の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
Ｙ１は、－ＣＨ３またはフッ素原子を表す。ｍは０または１である。ｎは０または１である。＊印はキラル中心を示す。）
Ｘ９～Ｘ２０は、それぞれ独立して－ＣＨ３、－ＣＦ３、ハロゲン原子または水素原子を表す。ただし、Ｘ９～Ｘ２０のうち１つ以上は、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子である。
Ｋは、単結合またはシクロヘキサン環を表す。） (In the above formula (3), R 3 is a saturated or unsaturated alkyl or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
Y 1 represents —CH 3 or a fluorine atom. m is 0 or 1. n is 0 or 1. * Indicates a chiral center. )
X 9 to X 20 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 9 to X 20 are each independently —CH 3 , —CF 3 or a halogen atom.
K represents a single bond or a cyclohexane ring. )
　上記式（２）において、Ｋは、単結合またはシクロヘキサン環を表す。Ｋが単結合である場合、下記一般式（２－１）で表されるように、キラル化合物Ｂは４個のベンゼン環が直接結合されたものとなる。Ｋがシクロヘキサン環である場合、下記一般式（２－２）で表されるように、キラル化合物Ｂは４個のベンゼン環と１個のシクロヘキサン環とが直接結合されたものとなる。中でも、Ｋは単結合であることが好ましい。 In the above formula (2), K represents a single bond or a cyclohexane ring. When K is a single bond, as represented by the following general formula (2-1), the chiral compound B is a compound in which four benzene rings are directly bonded. When K is a cyclohexane ring, the chiral compound B is obtained by directly bonding four benzene rings and one cyclohexane ring, as represented by the following general formula (2-2). Among these, K is preferably a single bond.
Figure JPOXMLDOC01-appb-C000015
Figure JPOXMLDOC01-appb-C000015
（上記式（２－１）および（２－２）において、Ｒ４、Ｒ５、Ｘ９～Ｘ２０は、上記式（２）と同様である。） (In the above formulas (2-1) and (2-2), R 4 , R 5 , and X 9 to X 20 are the same as in the above formula (2).)
　上記式（２）において、Ｒ４は、非キラルな基であり、ハロゲン原子で置換されていてもよい炭素数４～１８の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
　炭素数は４～１８であればよいが、中でも６～１８が好ましく、６～１２がさらに好ましい。炭素数が上記範囲よりも多いと、キラル化合物Ｂの合成が困難となり、コストが嵩むからである。一方、炭素数が上記範囲よりも少ないと、強誘電性液晶組成物がスメクチック相を発現しない場合があるからである。なお、アルキル基およびアルコシキアルキル基がハロゲン原子で置換されている場合には、炭素数が比較的少なくとも、強誘電性液晶組成物がスメクチック相を発現する場合がある。
　アルキル基またはアルコシキアルキル基は、ハロゲン原子で置換されていてもよく、ハロゲン原子で置換されていなくてもよいが、中でも、ハロゲン原子で置換されていないことが好ましい。
　アルキル基またはアルコキシアルキル基は、直鎖状または分岐状である。
　アルキル基またはアルコシキアルキル基は、飽和であっても不飽和であってもよいが、中でも飽和であることが好ましい。環状の不飽和アルカン以外の不飽和アルカンにおいては、不飽和アルカンは飽和アルカンに比べて反応性が高く、長期の保存・駆動や温度変化により材質が変化し、表示品質が劣化するおそれがあるからである。
　Ｒ４はアルキル基であってもアルコキシアルキル基であってもよいが、中でもアルキル基であることが好ましい。 In the above formula (2), R 4 is a non-chiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
The number of carbon atoms may be 4 to 18, but 6 to 18 is preferable and 6 to 12 is more preferable. This is because when the number of carbon atoms is larger than the above range, the synthesis of the chiral compound B becomes difficult and the cost increases. On the other hand, if the number of carbon atoms is less than the above range, the ferroelectric liquid crystal composition may not exhibit a smectic phase. In addition, when the alkyl group and the alkoxyalkyl group are substituted with a halogen atom, the ferroelectric liquid crystal composition may exhibit a smectic phase with a relatively small number of carbon atoms.
The alkyl group or alkoxyalkyl group may be substituted with a halogen atom or may not be substituted with a halogen atom, but is preferably not substituted with a halogen atom.
The alkyl group or alkoxyalkyl group is linear or branched.
The alkyl group or alkoxyalkyl group may be saturated or unsaturated, but is preferably saturated. In unsaturated alkanes other than cyclic unsaturated alkanes, unsaturated alkanes are more reactive than saturated alkanes, and the display quality may be deteriorated due to changes in materials due to long-term storage / driving and temperature changes. It is.
R 4 may be an alkyl group or an alkoxyalkyl group, but is preferably an alkyl group.
　上記式（２）において、Ｒ５は、１個以上のキラル中心をもつキラルな基であり、上記式（３）で表される基である。 In the above formula (2), R 5 is a chiral group having one or more chiral centers, and is a group represented by the above formula (3).
　上記式（３）において、Ｒ３は、ハロゲン原子で置換されていてもよい炭素数１～１０の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
　アルキル基またはアルコキシアルキル基は、直鎖状、分岐状または環状である。
　Ｒ３はアルキル基であってもアルコキシアルキル基であってもよいが、中でもアルキル基であることが好ましい。 In the above formula (3), R 3 is a saturated or unsaturated alkyl group or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
The alkyl group or alkoxyalkyl group is linear, branched or cyclic.
R 3 may be an alkyl group or an alkoxyalkyl group, but is preferably an alkyl group.
　上記式（３）において、Ｙ１は、－ＣＨ３またはフッ素原子を表す。－ＣＨ３の場合には、キラル化合物Ｂの合成が容易であるという利点を有する。一方、フッ素原子の場合、液晶分子の自発分極の大きさを大きくすることができ、応答速度を速くすることができるという利点もある。
　Ｙ１は－ＣＨ３であってもフッ素原子であってもよいが、中でも－ＣＨ３であることが好ましい。上述したようにキラル化合物Ｂの合成が容易であり、安定してキラル化合物Ｂを製造することができ、強誘電性液晶組成物を安価に得ることができるからである。 In the above formula (3), Y 1 represents —CH 3 or a fluorine atom. In the case of —CH 3 , there is an advantage that the synthesis of the chiral compound B is easy. On the other hand, in the case of fluorine atoms, there is an advantage that the magnitude of the spontaneous polarization of the liquid crystal molecules can be increased and the response speed can be increased.
Y 1 may be —CH 3 or a fluorine atom, and among them, —CH 3 is preferable. This is because the chiral compound B can be easily synthesized as described above, the chiral compound B can be stably produced, and a ferroelectric liquid crystal composition can be obtained at a low cost.
　上記式（３）において、ｍは０または１である。
　また、上記式（３）において、＊印はキラル中心を示す。ｍ＝０のとき、１位の炭素原子がキラル中心となり、ｍ＝１のとき、２位の炭素原子がキラル中心となる。 In the above formula (3), m is 0 or 1.
In the above formula (3), * indicates a chiral center. When m = 0, the 1st carbon atom becomes a chiral center, and when m = 1, the 2nd carbon atom becomes a chiral center.
　上記式（３）において、ｎは０または１である。 In the above formula (3), n is 0 or 1.
　上記式（２）において、Ｘ９～Ｘ２０は、それぞれ独立して－ＣＨ３、－ＣＦ３、ハロゲン原子または水素原子を表す。ただし、Ｘ９～Ｘ２０のうち１つ以上は、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子である。
　Ｘ９～Ｘ２０のすべてが水素原子である場合には、キラル化合物Ｂの溶解性が低下するため、キラル化合物Ｂの合成、精製が困難になり、コストが高くなったり、また強誘電性液晶組成物が結晶化しやすいものとなり、所望の耐衝撃性が得られなかったりするおそれがある。これに対し、本発明のようにＸ９～Ｘ２０のうち１つ以上が－ＣＨ３、－ＣＦ３またはハロゲン原子である場合には、キラル化合物Ｂの溶媒への溶解性が高くなり、大量合成、精製が可能になる。また、キラル化合物Ｂの立体構造に歪みが生じ、この歪みによって強誘電性液晶組成物の結晶化が阻害されるので、高い耐衝撃性を得ることができると考えられる。 In the above formula (2), X 9 to X 20 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 9 to X 20 are each independently —CH 3 , —CF 3 or a halogen atom.
When all of X 9 to X 20 are hydrogen atoms, the solubility of the chiral compound B decreases, so that the synthesis and purification of the chiral compound B becomes difficult, the cost increases, and the ferroelectric liquid crystal The composition is easily crystallized, and the desired impact resistance may not be obtained. In contrast, when at least one of X 9 to X 20 is —CH 3 , —CF 3 or a halogen atom as in the present invention, the solubility of the chiral compound B in the solvent is increased, and a large amount Synthesis and purification become possible. In addition, since the steric structure of the chiral compound B is distorted and the crystallization of the ferroelectric liquid crystal composition is inhibited by the distortion, it is considered that high impact resistance can be obtained.
　中でも、Ｘ９～Ｘ１３、Ｘ１５～Ｘ１９のいずれか１つ以上が、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子であることが好ましい。Ｘ９～Ｘ１３、Ｘ１５～Ｘ１９の位置に置換基を有する場合はＸ１４、Ｘ２０の位置の場合よりもキラル化合物の溶解性が良いからである。これは、Ｘ１４、Ｘ２０の位置の場合は他の位置の場合に比べて置換基による歪みが少ないためであると考えられる。 Among these, any one or more of X 9 to X 13 and X 15 to X 19 are preferably each independently —CH 3 , —CF 3 or a halogen atom. This is because the chiral compound has better solubility than the X 14 and X 20 positions when it has a substituent at the X 9 to X 13 and X 15 to X 19 positions. This is presumably because the X 14 and X 20 positions are less distorted by substituents than the other positions.
　Ｘ９～Ｘ２０が結合している３個のベンゼン環のうち、置換基を有するベンゼン環は、１～４個の置換基を有することができるが、中でも１個の置換基を有することが好ましい。すなわち、Ｘ９、Ｘ１０、Ｘ１５、Ｘ１６が結合しているベンゼン環が置換基を有する場合には、Ｘ９、Ｘ１０、Ｘ１５、Ｘ１６のうちいずれか１つが、－ＣＨ３、－ＣＦ３またはハロゲン原子であることが好ましい。Ｘ１１、Ｘ１２、Ｘ１７、Ｘ１８が結合しているベンゼン環が置換基を有する場合には、Ｘ１１、Ｘ１２、Ｘ１７、Ｘ１８のうちいずれか１つが、－ＣＨ３、－ＣＦ３またはハロゲン原子であることが好ましい。Ｘ１３、Ｘ１４、Ｘ１９、Ｘ２０が結合しているベンゼン環が置換基を有する場合には、Ｘ１３、Ｘ１４、Ｘ１９、Ｘ２０のうちいずれか１つが、－ＣＨ３、－ＣＦ３またはハロゲン原子であることが好ましい。
　特に、Ｘ９～Ｘ２０が結合している３個のベンゼン環のうち、１個または２個のベンゼン環がそれぞれ１個の置換基を有することが好ましい。すなわち、Ｘ９～Ｘ２０が結合している３個のベンゼン環の置換基の合計数は１個または２個であることが好ましい。 Of the three benzene rings to which X 9 to X 20 are bonded, the benzene ring having a substituent can have 1 to 4 substituents, and among them, it can have one substituent. preferable. That is, when the benzene ring to which X 9 , X 10 , X 15 , and X 16 are bonded has a substituent, any one of X 9 , X 10 , X 15 , and X 16 is —CH 3 , —CF 3 or a halogen atom is preferable. When the benzene ring to which X 11 , X 12 , X 17 , and X 18 are bonded has a substituent, any one of X 11 , X 12 , X 17 , and X 18 is —CH 3 , — CF 3 or a halogen atom is preferred. When the benzene ring to which X 13 , X 14 , X 19 and X 20 are bonded has a substituent, any one of X 13 , X 14 , X 19 and X 20 is —CH 3 , — CF 3 or a halogen atom is preferred.
In particular, it is preferable that one or two benzene rings each have one substituent among the three benzene rings to which X 9 to X 20 are bonded. That is, the total number of substituents of the three benzene rings to which X 9 to X 20 are bonded is preferably 1 or 2.
　また、置換基を有するベンゼン環が、２個の置換基を有することも好ましい。この場合、上記キラル化合物Ａと同様に、上記２個の置換基の位置としては、例えばＸ９およびＸ１０がフッ素原子である場合のようにベンゼン環の隣り合う炭素原子にそれぞれフッ素原子が置換していることが好ましい。
　さらに、Ｘ９～Ｘ２０が結合している３個のベンゼン環のうち、１個のベンゼン環が２個の置換基を有することが好ましい。すなわち、Ｘ９～Ｘ２０が結合している３個のベンゼン環の置換基の合計数が２個であり、１個のベンゼン環が２個の置換基を有することも好ましい。中でも、Ｘ９、Ｘ１０、Ｘ１５、Ｘ１６またはＸ１１、Ｘ１２、Ｘ１７、Ｘ１８が結合しているベンゼン環が２個の置換基を有することが好ましい。直接結合された４個のベンゼン環のうち、真ん中に位置するベンゼン環が置換基を有することにより、強誘電性液晶組成物が結晶化しにくくなるからである。
　特に、Ｘ９およびＸ１０、Ｘ１１およびＸ１２、Ｘ１５およびＸ１６、または、Ｘ１７およびＸ１８がフッ素原子であることが好ましい。 Moreover, it is also preferable that the benzene ring which has a substituent has two substituents. In this case, as in the case of the chiral compound A, the position of the two substituents is such that, for example, when X 9 and X 10 are fluorine atoms, the adjacent carbon atoms of the benzene ring are each substituted with a fluorine atom. It is preferable.
Further, it is preferable that one of the three benzene rings to which X 9 to X 20 are bonded has one substituent. That is, it is also preferable that the total number of substituents of the three benzene rings to which X 9 to X 20 are bonded is two, and that one benzene ring has two substituents. Among them, it is preferable that the benzene ring to which X 9 , X 10 , X 15 , X 16 or X 11 , X 12 , X 17 , X 18 is bonded has two substituents. This is because, among the four directly bonded benzene rings, the ferroelectric liquid crystal composition is difficult to crystallize because the middle benzene ring has a substituent.
In particular, X 9 and X 10 , X 11 and X 12 , X 15 and X 16 , or X 17 and X 18 are preferably fluorine atoms.
　また、ベンゼン環が有する置換基は、置換基が１個の場合には－ＣＨ３、フッ素原子または塩素原子であることが好ましく、－ＣＨ３またはフッ素原子であることが特に好ましい。一方、置換基が２個の場合にはいずれの置換基もフッ素原子であることが好ましい。なお、ベンゼン環に２個のフッ素原子が置換している場合には、上記２個のフッ素原子は隣り合う炭素原子にそれぞれ置換していることが好ましい。 Further, the substituent that the benzene ring has is preferably —CH 3 , a fluorine atom, or a chlorine atom, and particularly preferably —CH 3 or a fluorine atom, when there is one substituent. On the other hand, when there are two substituents, it is preferable that any substituent is a fluorine atom. When two fluorine atoms are substituted on the benzene ring, the two fluorine atoms are preferably substituted with adjacent carbon atoms.
　さらに、Ｘ９～Ｘ２０が結合している３個のベンゼン環の置換基の合計数は３～８個であることも好ましい。置換基の合計数が多いことにより、強誘電性液晶組成物の結晶化を抑制することができるからである。特に置換基の合計数は３～５個であることが好ましく、３個であることがより好ましい。
　Ｘ９～Ｘ２０が結合している３個のベンゼン環が合計で３～８個の置換基を有する場合、置換基の位置としては、Ｘ１１、Ｘ１２、Ｘ１７、Ｘ１８が結合しているベンゼン環が２個の置換基を有し、Ｘ９、Ｘ１０、Ｘ１５、Ｘ１６が結合しているベンゼン環、およびＸ１３、Ｘ１４、Ｘ１９、Ｘ２０が結合しているベンゼン環がそれぞれ０～３個、合計で１～６個の置換基を有することが好ましい。この場合には、強誘電性液晶組成物の結晶化を効果的に抑制することができ、低温で安定して液晶表示素子を駆動することが可能となる。また、強誘電性液晶組成物におけるキラル化合物の含有量が制限されるのを防ぐことができる。中でも、Ｘ１１、Ｘ１２、Ｘ１７、Ｘ１８が結合しているベンゼン環が２個の置換基を有し、Ｘ９、Ｘ１０、Ｘ１５、Ｘ１６が結合しているベンゼン環が１～３個の置換基を有することが好ましい。直接結合されたベンゼン環のうち、真ん中に位置するベンゼン環が置換基を有することにより、強誘電性液晶組成物の結晶化が効果的に抑制されるからである。
　また、置換基の合計数は３個であることが好ましいことから、Ｘ１１、Ｘ１２、Ｘ１７、Ｘ１８が結合しているベンゼン環が２個の置換基を有し、Ｘ９、Ｘ１０、Ｘ１５、Ｘ１６が結合しているベンゼン環、またはＸ１３、Ｘ１４、Ｘ１９、Ｘ２０が結合しているベンゼン環が１個の置換基を有することが好ましい。中でも、Ｘ１１、Ｘ１２、Ｘ１７、Ｘ１８が結合しているベンゼン環が２個の置換基を有し、Ｘ９、Ｘ１０、Ｘ１５、Ｘ１６が結合しているベンゼン環が結合しているベンゼン環が１個の置換基を有することがより好ましい。上述のように、真ん中に位置するベンゼン環が置換基を有することにより、強誘電性液晶組成物の結晶化が効果的に抑制されるからである。
　この場合、ベンゼン環が有する置換基としては、Ｘ９、Ｘ１０、Ｘ１５、Ｘ１６が結合しているベンゼン環、およびＸ１３、Ｘ１４、Ｘ１９、Ｘ２０が結合しているベンゼン環が有する置換基は－ＣＨ３、－ＣＦ３またはハロゲン原子であることが好ましく、中でも－ＣＨ３であることが好ましい。また、Ｘ１１、Ｘ１２、Ｘ１７、Ｘ１８が結合しているベンゼン環が有する置換基はフッ素原子であることが好ましい。
　特に、置換基の合計数が３個である場合には、Ｘ９またはＸ１０が－ＣＨ3であり、Ｘ１１およびＸ１２がフッ素原子であることが好ましい。 Furthermore, the total number of substituents on the three benzene rings to which X 9 to X 20 are bonded is preferably 3 to 8. This is because when the total number of substituents is large, crystallization of the ferroelectric liquid crystal composition can be suppressed. In particular, the total number of substituents is preferably 3 to 5, more preferably 3.
When the three benzene rings to which X 9 to X 20 are bonded have a total of 3 to 8 substituents, X 11 , X 12 , X 17 and X 18 are bonded as the positions of the substituents. Benzene ring having two substituents, benzene ring to which X 9 , X 10 , X 15 , and X 16 are bonded, and X 13 , X 14 , X 19 , and X 20 are bonded to each other Each of the benzene rings preferably has 0 to 3 substituents in total, 1 to 6 substituents. In this case, crystallization of the ferroelectric liquid crystal composition can be effectively suppressed, and the liquid crystal display element can be driven stably at a low temperature. Moreover, it can prevent that content of the chiral compound in a ferroelectric liquid-crystal composition is restrict | limited. Among them, the benzene ring to which X 11 , X 12 , X 17 and X 18 are bonded has two substituents, and the benzene ring to which X 9 , X 10 , X 15 and X 16 are bonded is 1 It preferably has ˜3 substituents. This is because, among the directly bonded benzene rings, the benzene ring located in the middle has a substituent, so that the crystallization of the ferroelectric liquid crystal composition is effectively suppressed.
Since the total number of substituents is preferably 3, the benzene ring to which X 11 , X 12 , X 17 and X 18 are bonded has two substituents, and X 9 , X The benzene ring to which 10 , X 15 , and X 16 are bonded, or the benzene ring to which X 13 , X 14 , X 19 , and X 20 are bonded preferably has one substituent. Among them, the benzene ring to which X 11 , X 12 , X 17 and X 18 are bonded has two substituents, and the benzene ring to which X 9 , X 10 , X 15 and X 16 are bonded. More preferably, the benzene ring having one substituent has one substituent. This is because, as described above, when the benzene ring located in the middle has a substituent, crystallization of the ferroelectric liquid crystal composition is effectively suppressed.
In this case, examples of the substituent that the benzene ring has include a benzene ring to which X 9 , X 10 , X 15 and X 16 are bonded, and a benzene ring to which X 13 , X 14 , X 19 and X 20 are bonded. The substituent that is possessed is preferably —CH 3 , —CF 3 or a halogen atom, and more preferably —CH 3 . Further, it is preferable that X 11, X 12, X 17 , substituent group of the benzene ring X 18 is attached is a fluorine atom.
In particular, when the total number of substituents is 3, X 9 or X 10 is preferably —CH 3 , and X 11 and X 12 are preferably fluorine atoms.
　上記式（２）で表されるキラル化合物Ｂの具体例としては、下記一般式（２－３）～（２－１２）で表されるキラル化合物Ｂが挙げられる。 Specific examples of the chiral compound B represented by the above formula (2) include chiral compounds B represented by the following general formulas (2-3) to (2-12).
Figure JPOXMLDOC01-appb-C000016
Figure JPOXMLDOC01-appb-C000016
（上記式（２－３）～（２－１２）において、Ｒ１２は炭素数１～１０の飽和または不飽和のアルキル基であり、＊印はキラル中心を示し、ｍは０または１であり、ｖは４～１８であり、Ｘ３１～Ｘ３４はそれぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子を表し、上記式（２－３）～（２－６）におけるｒ、ｓおよびｔはいずれか１つまたは２つが１、残りが０であり、上記式（２－７）～（２－１０）におけるｕおよびｗは一方が１、他方が０である。） (In the above formulas (2-3) to (2-12), R 12 is a saturated or unsaturated alkyl group having 1 to 10 carbon atoms, * represents a chiral center, and m is 0 or 1. , V is 4 to 18, and X 31 to X 34 each independently represent —CH 3 , —CF 3 or a halogen atom, and r, s and in the above formulas (2-3) to (2-6) t is any one or two and the rest is 0, and one of u and w in the above formulas (2-7) to (2-10) is 1 and the other is 0.
　上記式（２－３）～（２－１２）において、ｖは４～１８であり、好ましくは６～１８、より好ましくは６～１２である。上述したように、炭素数が上記範囲よりも多いと、キラル化合物Ｂの合成が困難となるからである。一方、炭素数が上記範囲よりも少ないと、強誘電性液晶組成物がスメクチック相を発現しない場合があるからである。 In the above formulas (2-3) to (2-12), v is 4 to 18, preferably 6 to 18, and more preferably 6 to 12. As described above, when the number of carbon atoms is larger than the above range, the synthesis of chiral compound B becomes difficult. On the other hand, if the number of carbon atoms is less than the above range, the ferroelectric liquid crystal composition may not exhibit a smectic phase.
　上記式（２－３）～（２－１２）において、Ｒ１２は炭素数１～１０の飽和または不飽和のアルキル基である。アルキル基は、直鎖状、分岐状または環状である。中でも、Ｒ１２は、直鎖状もしくは分岐状の飽和のアルキル基、またはフェニルアルキル基であることが好ましい。 In the above formulas (2-3) to (2-12), R 12 is a saturated or unsaturated alkyl group having 1 to 10 carbon atoms. The alkyl group is linear, branched or cyclic. Among them, R 12 is preferably a linear or branched saturated alkyl group or a phenylalkyl group.
　上記式（２－４）、（２－６）、（２－８）、（２－１０）および（２－１２）において、ｍは０または１である。
　また、上記式（２－３）～（２－１２）において、＊印はキラル中心を示す。上記式（２－３）、（２－５）、（２－７）、（２－９）および（２－１１）では、１位の炭素原子がキラル中心となる。上記式（２－４）、（２－６）、（２－８）、（２－１０）および（２－１２）では、ｍ＝０のとき、１位の炭素原子がキラル中心となり、ｍ＝１のとき、２位の炭素原子がキラル中心となる。 In the above formulas (2-4), (2-6), (2-8), (2-10) and (2-12), m is 0 or 1.
In the above formulas (2-3) to (2-12), * indicates a chiral center. In the above formulas (2-3), (2-5), (2-7), (2-9) and (2-11), the carbon atom at the 1-position is the chiral center. In the above formulas (2-4), (2-6), (2-8), (2-10) and (2-12), when m = 0, the carbon atom at the 1-position becomes a chiral center and m When = 1, the carbon atom at the 2-position is a chiral center.
　上記式（２－３）～（２－６）および（２－１１）～（２－１２）において、Ｘ３１～Ｘ３４は、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子を表す。中でも、－ＣＨ３、フッ素原子または塩素原子が好ましく、特に－ＣＨ３またはフッ素原子が好ましい。
　Ｘ３１～Ｘ３４の位置としては、上述のＸ９～Ｘ２０の位置と同様である。 In the above formulas (2-3) to (2-6) and (2-11) to (2-12), X 31 to X 34 each independently represent —CH 3 , —CF 3 or a halogen atom. . Among them, —CH 3 , a fluorine atom or a chlorine atom is preferable, and —CH 3 or a fluorine atom is particularly preferable.
The positions of X 31 to X 34 are the same as the positions of X 9 to X 20 described above.
　上記式（２－３）～（２－６）で表されるキラル化合物Ｂの具体例としては、下記式で表されるキラル化合物Ｂを挙げることができる。 Specific examples of the chiral compound B represented by the above formulas (2-3) to (2-6) include a chiral compound B represented by the following formula.
Figure JPOXMLDOC01-appb-C000017
Figure JPOXMLDOC01-appb-C000017
Figure JPOXMLDOC01-appb-C000018
Figure JPOXMLDOC01-appb-C000018
　また上記式（２－７）～（２－１０）で表されるキラル化合物Ｂの具体例としては、下記式で表されるキラル化合物Ｂを挙げることができる。なお、以下、右旋性を（＋）、左旋性を（－）で示す。 Further, specific examples of the chiral compound B represented by the above formulas (2-7) to (2-10) include a chiral compound B represented by the following formula. In the following, dextrorotatory property is indicated by (+) and levorotatory property is indicated by (−).
Figure JPOXMLDOC01-appb-C000019
Figure JPOXMLDOC01-appb-C000019
　また上記式（２－１１）で表されるキラル化合物Ｂの具体例としては、下記式で表されるキラル化合物Ｂを挙げることができる。 Further, specific examples of the chiral compound B represented by the above formula (2-11) include a chiral compound B represented by the following formula.
Figure JPOXMLDOC01-appb-C000020
Figure JPOXMLDOC01-appb-C000020
　このようなキラル化合物Ｂとしては、１種を単独で用いてもよく、２種以上を混合して用いてもよい。
　例えば、強誘電性液晶組成物が、上記式（２－１）で表されるキラル化合物Ｂと上記式（２－２）で表されるキラル化合物Ｂとを含有していてもよい。 As such a chiral compound B, 1 type may be used independently and 2 or more types may be mixed and used for it.
For example, the ferroelectric liquid crystal composition may contain a chiral compound B represented by the above formula (2-1) and a chiral compound B represented by the above formula (2-2).
　強誘電性液晶組成物中のキラル化合物Ｂの含有量としては、耐衝撃性の効果が得られる程度であれば特に限定されるものではない。上記キラル化合物Ｂを１種単独で用いる場合にはそのキラル化合物Ｂの含有量が、上記キラル化合物Ｂを２種以上混合する場合には２種以上のキラル化合物Ｂの各含有量が、強誘電性液晶組成物中にて５質量％以上であることが好ましい。 The content of the chiral compound B in the ferroelectric liquid crystal composition is not particularly limited as long as an impact resistance effect is obtained. When the chiral compound B is used alone, the content of the chiral compound B is ferroelectric. When two or more kinds of the chiral compound B are mixed, each content of the two or more chiral compounds B is ferroelectric. It is preferable that it is 5 mass% or more in a crystalline liquid crystal composition.
　キラル化合物Ｂは、例えば、国際公開第２０１０／０３１４３１号パンフレットに記載の方法により合成することができる。 Chiral compound B can be synthesized, for example, by the method described in International Publication No. 2010/031431.
　（ｃ）キラル化合物Ａおよびキラル化合物Ｂ
　本発明において、強誘電性液晶組成物は、キラル化合物Ａおよびキラル化合物Ｂの少なくともいずれかを含有していればよく、例えば、キラル化合物Ａのみを含有していてもよく、キラル化合物Ｂのみを含有していてもよく、キラル化合物Ａおよびキラル化合物Ｂを含有していてもよい。また、強誘電性液晶組成物がキラル化合物Ａを含有する場合、１種類のキラル化合物Ａを含有していてもよく、２種類以上のキラル化合物Ａを含有していてもよい。同様に、強誘電性液晶組成物がキラル化合物Ｂを含有する場合、１種類のキラル化合物Ｂを含有していてもよく、２種類以上のキラル化合物Ｂを含有していてもよい。 (C) Chiral compound A and chiral compound B
In the present invention, the ferroelectric liquid crystal composition only needs to contain at least one of the chiral compound A and the chiral compound B. For example, the ferroelectric liquid crystal composition may contain only the chiral compound A or only the chiral compound B. It may contain, and the chiral compound A and the chiral compound B may be contained. Further, when the ferroelectric liquid crystal composition contains the chiral compound A, it may contain one kind of chiral compound A or two or more kinds of chiral compounds A. Similarly, when the ferroelectric liquid crystal composition contains the chiral compound B, it may contain one kind of chiral compound B or may contain two or more kinds of chiral compounds B.
　強誘電性液晶組成物がキラル化合物Ａのみを含有する場合、強誘電性液晶組成物中のキラル化合物Ａの含有量としては、耐衝撃性の効果が得られる程度であれば特に限定されるものではない。上記キラル化合物Ａを１種単独で用いる場合にはそのキラル化合物Ａの含有量が、上記キラル化合物Ａを２種以上混合する場合には２種以上のキラル化合物Ａの各含有量が、強誘電性液晶組成物中にて５質量％以上であることが好ましい。中でも、上記キラル化合物Ａを１種単独で用いる場合にはそのキラル化合物Ａの含有量が、上記キラル化合物Ａを２種以上混合する場合には２種以上のキラル化合物Ａの合計含有量が、強誘電性液晶組成物中で５質量％～３５質量％の範囲内であることが好ましく、１５質量％～３０質量％の範囲内であることがより好ましい。キラル化合物Ａの含有量が上記範囲よりも少ないと、所望の耐衝撃性が得られない場合があり、一方、キラル化合物Ａの含有量が上記範囲よりも多いと、強誘電性液晶組成物が、粘度が高くなったり、結晶化しやすくなったりして、十分な耐衝撃性が得られない場合があり、また液晶表示素子を作製する際に液晶層の形成が困難となる場合があるからである。 When the ferroelectric liquid crystal composition contains only the chiral compound A, the content of the chiral compound A in the ferroelectric liquid crystal composition is particularly limited as long as an impact resistance effect is obtained. is not. When one of the above chiral compounds A is used alone, the content of the chiral compound A is ferroelectric. When two or more of the above chiral compounds A are mixed, each content of two or more of the chiral compounds A is ferroelectric. It is preferable that it is 5 mass% or more in a crystalline liquid crystal composition. Among them, when the chiral compound A is used alone, the content of the chiral compound A is, and when two or more chiral compounds A are mixed, the total content of the two or more chiral compounds A is In the ferroelectric liquid crystal composition, it is preferably in the range of 5% by mass to 35% by mass, and more preferably in the range of 15% by mass to 30% by mass. If the content of the chiral compound A is less than the above range, the desired impact resistance may not be obtained. On the other hand, if the content of the chiral compound A is more than the above range, the ferroelectric liquid crystal composition may be obtained. In some cases, the viscosity becomes high or the crystallized easily, and sufficient impact resistance may not be obtained, and it may be difficult to form a liquid crystal layer when manufacturing a liquid crystal display element. is there.
　強誘電性液晶組成物がキラル化合物Ｂのみを含有する場合、強誘電性液晶組成物中のキラル化合物Ｂの含有量としては、耐衝撃性の効果が得られる程度であれば特に限定されるものではない。上記キラル化合物Ｂを１種単独で用いる場合にはそのキラル化合物Ｂの含有量が、上記キラル化合物Ｂを２種以上混合する場合には２種以上のキラル化合物Ｂの各含有量が、強誘電性液晶組成物中にて５質量％以上であることが好ましい。中でも、上記キラル化合物Ｂを１種単独で用いる場合にはそのキラル化合物Ｂの含有量が、上記キラル化合物Ｂを２種以上混合する場合には２種以上のキラル化合物Ｂの合計含有量が、強誘電性液晶組成物中で５質量％～３５質量％の範囲内であることが好ましく、１５質量％～３０質量％の範囲内であることがより好ましい。キラル化合物Ｂの含有量が上記範囲よりも少ないと、所望の耐衝撃性が得られない場合があり、一方、キラル化合物Ｂの含有量が上記範囲よりも多いと、強誘電性液晶組成物が、粘度が高くなったり、結晶化しやすくなったりして、十分な耐衝撃性が得られない場合があり、また液晶表示素子を作製する際に液晶層の形成が困難となる場合があるからである。 When the ferroelectric liquid crystal composition contains only the chiral compound B, the content of the chiral compound B in the ferroelectric liquid crystal composition is particularly limited as long as an impact resistance effect is obtained. is not. When the chiral compound B is used alone, the content of the chiral compound B is ferroelectric. When two or more kinds of the chiral compound B are mixed, each content of the two or more chiral compounds B is ferroelectric. It is preferable that it is 5 mass% or more in a crystalline liquid crystal composition. Among them, when the chiral compound B is used alone, the content of the chiral compound B is, and when two or more chiral compounds B are mixed, the total content of the two or more chiral compounds B is: In the ferroelectric liquid crystal composition, it is preferably in the range of 5% by mass to 35% by mass, and more preferably in the range of 15% by mass to 30% by mass. If the content of the chiral compound B is less than the above range, the desired impact resistance may not be obtained. On the other hand, if the content of the chiral compound B is more than the above range, the ferroelectric liquid crystal composition may be obtained. In some cases, the viscosity becomes high or the crystallized easily, and sufficient impact resistance may not be obtained, and it may be difficult to form a liquid crystal layer when manufacturing a liquid crystal display element. is there.
　また、強誘電性液晶組成物がキラル化合物Ｂのみを含有する場合であって、上記式（２－１）で表される４個のベンゼン環が直接結合されたキラル化合物Ｂ１と上記式（２－２）で表される４個のベンゼン環および１個のシクロヘキサン環が直接結合されたキラル化合物Ｂ２とを含有する場合、強誘電性液晶組成物中のキラル化合物Ｂ１の含有量は、キラル化合物Ｂ２の含有量以上であることが好ましい。キラル化合物Ｂ２はキラル化合物Ｂ１と比較して、電圧を印加したときの液晶分子のチルト角を小さくする傾向があるので、キラル化合物Ｂ１に比べてキラル化合物Ｂ２の含有量を多くすると、液晶分子のチルト角が小さくなり、明るさが十分得られないおそれがある。これに対し、キラル化合物Ｂ１がキラル化合物Ｂ２に比べて多く含有されていることにより、液晶分子のチルト角を大きくすることができ、駆動性能を向上させることができる。 Further, when the ferroelectric liquid crystal composition contains only the chiral compound B, the chiral compound B1 in which four benzene rings represented by the above formula (2-1) are directly bonded and the above formula (2) -2), the chiral compound B1 in the ferroelectric liquid crystal composition contains the chiral compound B2 in which four benzene rings and one cyclohexane ring directly bonded to each other are contained. It is preferable that it is more than the content of B2. Since the chiral compound B2 has a tendency to reduce the tilt angle of the liquid crystal molecules when a voltage is applied as compared with the chiral compound B1, if the content of the chiral compound B2 is increased compared to the chiral compound B1, the liquid crystal molecules There is a possibility that the tilt angle becomes small and sufficient brightness cannot be obtained. On the other hand, when the chiral compound B1 is contained in a larger amount than the chiral compound B2, the tilt angle of the liquid crystal molecules can be increased, and the driving performance can be improved.
　強誘電性液晶組成物がキラル化合物Ａおよびキラル化合物Ｂを含有する場合、強誘電性液晶組成物中のキラル化合物Ａおよびキラル化合物Ｂの合計含有量としては、耐衝撃性の効果が得られる程度であれば特に限定されるものではないが、５質量％～３５質量％の範囲内であることが好ましく、１５質量％～３０質量％の範囲内であることがより好ましい。キラル化合物Ａおよびキラル化合物Ｂの合計含有量上記範囲よりも少ないと、所望の耐衝撃性が得られない場合があり、一方、キラル化合物Ａおよびキラル化合物Ｂの合計含有量が上記範囲よりも多いと、強誘電性液晶組成物が、粘度が高くなったり、結晶化しやすくなったりして、十分な耐衝撃性が得られない場合があり、また液晶表示素子を作製する際に液晶層の形成が困難となる場合があるからである。 When the ferroelectric liquid crystal composition contains the chiral compound A and the chiral compound B, the total content of the chiral compound A and the chiral compound B in the ferroelectric liquid crystal composition is such that an impact resistance effect is obtained. If it is, it is not particularly limited, but it is preferably in the range of 5 to 35% by mass, more preferably in the range of 15 to 30% by mass. If the total content of chiral compound A and chiral compound B is less than the above range, the desired impact resistance may not be obtained, while the total content of chiral compound A and chiral compound B is more than the above range. In some cases, the ferroelectric liquid crystal composition has a high viscosity or is easily crystallized, so that sufficient impact resistance may not be obtained. In addition, when a liquid crystal display device is produced, a liquid crystal layer is formed. This may be difficult.
　また、強誘電性液晶組成物がキラル化合物Ａおよびキラル化合物Ｂを含有する場合、強誘電性液晶組成物中のキラル化合物Ｂの含有量は、キラル化合物Ａの含有量以上であることが好ましい。キラル化合物Ａはキラル化合物Ｂと比較して、電圧を印加したときの液晶分子のチルト角を小さくする傾向があるので、キラル化合物Ｂに比べてキラル化合物Ａの含有量を多くすると、液晶分子のチルト角が小さくなり、明るさが十分得られないおそれがある。これに対し、キラル化合物Ｂがキラル化合物Ａに比べて多く含まれていることにより、液晶分子のチルト角を大きくすることができ、駆動性能を向上させることができるからである。 In addition, when the ferroelectric liquid crystal composition contains the chiral compound A and the chiral compound B, the content of the chiral compound B in the ferroelectric liquid crystal composition is preferably not less than the content of the chiral compound A. Since the chiral compound A has a tendency to reduce the tilt angle of the liquid crystal molecules when a voltage is applied as compared with the chiral compound B, if the content of the chiral compound A is increased compared to the chiral compound B, the liquid crystal molecules There is a possibility that the tilt angle becomes small and sufficient brightness cannot be obtained. On the other hand, when the chiral compound B is contained in a larger amount than the chiral compound A, the tilt angle of the liquid crystal molecules can be increased and the driving performance can be improved.
　（２）ホスト液晶
　本発明における強誘電性液晶組成物は、上記キラル化合物の他に、ホスト液晶を含有していてもよい。 (2) Host liquid crystal The ferroelectric liquid crystal composition in the present invention may contain a host liquid crystal in addition to the chiral compound.
　ホスト液晶としては、強誘電性液晶組成物のホスト液晶として一般的に用いられるものを使用することができ、例えば、フェニルピリミジン化合物を挙げることができる。
　ホスト液晶は、１種を単独で用いてもよく、２種以上を混合して用いてもよい。 As the host liquid crystal, those generally used as the host liquid crystal of the ferroelectric liquid crystal composition can be used, and examples thereof include a phenylpyrimidine compound.
A host liquid crystal may be used individually by 1 type, and 2 or more types may be mixed and used for it.
　中でも、ホスト液晶として用いられるフェニルピリミジン化合物は、フェニル基がフッ素原子で置換されたものであることが好ましく、フェニル基が１個または２個のフッ素原子で置換されたものであることがより好ましい。フェニル基がフッ素原子で置換されたフェニルピリミジン化合物では、強誘電性液晶組成物におけるスメクチック液晶の相転移温度が広がるので、低温および高温で安定して液晶表示素子を駆動することが可能となるからである。また、強誘電性液晶組成物の粘度が低くなるので、液晶表示素子の製造工程にて液晶層の形成が容易となるという利点を有する。さらには、フェニル基がフッ素原子で置換されているフェニルピリミジン化合物を用いることにより、液晶表示素子を製造する際に強誘電性液晶組成物を塗布または滴下する場合には、塗布跡および滴下跡が生じにくくなるので、塗布跡や滴下跡による液晶分子の配向乱れを防ぎ、配向欠陥の発生を抑制することができる。なお、これは、フッ素原子により強誘電性液晶組成物と配向膜との相互作用が弱まり、強誘電性液晶組成物を塗布もしくは滴下した際に液晶分子が配向していない状態で配向膜に固着されてしまうのが抑制されるためであると推量される。 Among them, the phenylpyrimidine compound used as the host liquid crystal is preferably a phenyl group substituted with a fluorine atom, and more preferably a phenyl group substituted with one or two fluorine atoms. . In the phenylpyrimidine compound in which the phenyl group is substituted with a fluorine atom, the phase transition temperature of the smectic liquid crystal in the ferroelectric liquid crystal composition is widened, so that the liquid crystal display element can be driven stably at low and high temperatures. It is. Further, since the viscosity of the ferroelectric liquid crystal composition is lowered, there is an advantage that the liquid crystal layer can be easily formed in the manufacturing process of the liquid crystal display element. Furthermore, when a ferroelectric liquid crystal composition is applied or dropped when a liquid crystal display device is produced by using a phenylpyrimidine compound in which the phenyl group is substituted with a fluorine atom, the coating mark and the dropping mark are not observed. Since it becomes difficult to occur, it is possible to prevent alignment disorder of liquid crystal molecules due to coating marks and dropping marks, and to suppress the occurrence of alignment defects. This is because the fluorine atom weakens the interaction between the ferroelectric liquid crystal composition and the alignment film, and when the ferroelectric liquid crystal composition is applied or dropped, the liquid crystal molecules are not aligned and are fixed to the alignment film. It is guessed that this is because it is suppressed.
　このようなフェニルピリミジン化合物としては、具体的には、下記一般式（４－１）～（４－４）で表されるものを挙げることができる。 Specific examples of such phenylpyrimidine compounds include those represented by the following general formulas (4-1) to (4-4).
Figure JPOXMLDOC01-appb-C000021
Figure JPOXMLDOC01-appb-C000021
　上記式（４－１）～（４－４）において、Ｒ２１はアルキル基であり、Ｒ２２はアルコキシ基またはカルボキシル基である。 In the above formulas (4-1) to (4-4), R 21 is an alkyl group, and R 22 is an alkoxy group or a carboxyl group.
　また、フェニルピリミジン化合物は、１個のピリミジン環と１個のベンゼン環とを有する二環化合物、１個のピリミジン環と２個のベンゼン環とを有する三環化合物、１個のピリミジン環と１個のベンゼン環と１個のシクロヘキサン環とを有する三環化合物等のいずれであってもよい。
　中でも、フェニルピリミジン化合物としては、上記二環化合物に上記三環化合物を混合させて用いることが好ましい。フェニルピリミジン化合物として、上記二環化合物のみを用いるよりも、上記二環化合物に上記三環化合物を混合して用いるほうが、強誘電性液晶組成物のカイラルスメクチックＣ相の相転移温度が広がり、液晶表示素子に用いた場合に使用可能範囲が広がるからである。
　さらには、上記三環化合物の中でも、１個のピリミジン環と１個のベンゼン環と１個のシクロヘキサン環とを有する三環化合物を用いることが好ましい。１個のピリミジン環と１個のベンゼン環と１個のシクロヘキサン環とを有する三環化合物を用いた場合には、１個のピリミジン環と２個のベンゼン環とを有する三環化合物を用いた場合と比較して、共役系が短くなるため、強誘電性液晶組成物の複屈折が小さくなるので、液晶表示素子に適用した場合により広いセルギャップで使用可能となるからである。 The phenylpyrimidine compound is a bicyclic compound having one pyrimidine ring and one benzene ring, a tricyclic compound having one pyrimidine ring and two benzene rings, one pyrimidine ring and 1 Any of a tricyclic compound having one benzene ring and one cyclohexane ring may be used.
Especially, as a phenyl pyrimidine compound, it is preferable to mix the said tricyclic compound with the said bicyclic compound. As the phenylpyrimidine compound, when the tricyclic compound is mixed with the bicyclic compound rather than using only the bicyclic compound, the phase transition temperature of the chiral smectic C phase of the ferroelectric liquid crystal composition is increased. This is because the usable range is widened when used for a display element.
Furthermore, among the tricyclic compounds, it is preferable to use a tricyclic compound having one pyrimidine ring, one benzene ring, and one cyclohexane ring. When a tricyclic compound having one pyrimidine ring, one benzene ring, and one cyclohexane ring was used, a tricyclic compound having one pyrimidine ring and two benzene rings was used. This is because, since the conjugated system is shorter than the case, the birefringence of the ferroelectric liquid crystal composition is reduced, so that it can be used with a wider cell gap when applied to a liquid crystal display element.
　強誘電性液晶組成物中のホスト液晶の含有量としては、上記キラル化合物の含有量を上記範囲とすることができれば特に限定されるものではない。
　中でも、フェニルピリミジン化合物が、フェニル基がフッ素原子で置換されたものである場合には、強誘電性液晶組成物中のフェニルピリミジン化合物の含有量は１０質量％～３０質量％の範囲内であることが好ましい。フェニルピリミジン化合物の含有量が少ないと、上述の効果が十分に得られない場合があるからである。一方、フェニルピリミジン化合物の含有量が多すぎると、強誘電性液晶組成物が結晶化しやすくなるため、保存安定性が悪くなり、強誘電性液晶組成物に含まれる化合物の析出が起こり、表示品質が低下するおそれがあるからである。 The content of the host liquid crystal in the ferroelectric liquid crystal composition is not particularly limited as long as the content of the chiral compound can be within the above range.
In particular, when the phenylpyrimidine compound is a compound in which the phenyl group is substituted with a fluorine atom, the content of the phenylpyrimidine compound in the ferroelectric liquid crystal composition is in the range of 10% by mass to 30% by mass. It is preferable. This is because if the content of the phenylpyrimidine compound is small, the above effects may not be sufficiently obtained. On the other hand, when the content of the phenylpyrimidine compound is too large, the ferroelectric liquid crystal composition is easily crystallized, so that the storage stability is deteriorated and the compound contained in the ferroelectric liquid crystal composition is precipitated, resulting in display quality. It is because there exists a possibility that it may fall.
　（３）強誘電性液晶組成物
　本発明における強誘電性液晶組成物としては、カイラルスメクチックＣ（ＳｍＣ＊）相を発現するものであれば特に限定されるものではない。強誘電性液晶組成物の相系列としては、例えば、降温過程においてネマチック（Ｎ）相－コレステリック（Ｃｈ）相－カイラルスメクチックＣ（ＳｍＣ＊）相と相変化するもの、ネマチック（Ｎ）相－カイラルスメクチックＣ（ＳｍＣ＊）相と相変化するもの、ネマチック（Ｎ）相－スメクチックＡ（ＳｍＡ）相－カイラルスメクチックＣ（ＳｍＣ＊）相と相変化するもの、ネマチック（Ｎ）相－コレステリック（Ｃｈ）相－スメクチックＡ（ＳｍＡ）相－カイラルスメクチックＣ（ＳｍＣ＊）相と相変化するもの、などを挙げることができる。 (3) Ferroelectric liquid crystal composition The ferroelectric liquid crystal composition in the present invention is not particularly limited as long as it exhibits a chiral smectic C (SmC * ) phase. As the phase series of the ferroelectric liquid crystal composition, for example, a phase change between a nematic (N) phase, a cholesteric (Ch) phase, a chiral smectic C (SmC * ) phase and a nematic (N) phase-chiral in the temperature lowering process. Phase change with smectic C (SmC * ) phase, Nematic (N) phase-Smectic A (SmA) phase-Chiral smectic C (SmC * ) phase change, Nematic (N) phase-Cholesteric (Ch) Phase-smectic A (SmA) phase-chiral smectic C (SmC * ) phase and the like.
　また、強誘電性液晶組成物としては、双安定性を示すものおよび単安定性を示すもののいずれも用いることができる。中でも、単安定性を示す強誘電性液晶組成物が好ましい。単安定性を示す強誘電性液晶組成物を用いた場合には、電圧変化により液晶のダイレクタ（分子軸の傾き）を連続的に変化させ、透過光度をアナログ変調することで、階調表示が可能となるからである。特に、液晶表示素子をフィールドシーケンシャルカラー方式により駆動させる場合には、単安定性を示す強誘電性液晶組成物を用いることが好ましい。単安定性を示す強誘電性液晶組成物を用いることにより、ＴＦＴを用いたアクティブマトリックス方式による駆動が可能になり、また、電圧変調により階調制御が可能になり、高精細で高品位の表示を実現することができるからである。 Also, as the ferroelectric liquid crystal composition, any one showing bistability and one showing monostability can be used. Among these, a ferroelectric liquid crystal composition exhibiting monostability is preferable. When a ferroelectric liquid crystal composition exhibiting monostability is used, gradation display is achieved by continuously changing the director of the liquid crystal (inclination of the molecular axis) by changing the voltage and analog-modulating the transmitted light intensity. This is because it becomes possible. In particular, when the liquid crystal display element is driven by a field sequential color system, it is preferable to use a ferroelectric liquid crystal composition exhibiting monostability. By using a ferroelectric liquid crystal composition exhibiting monostability, it becomes possible to drive by an active matrix method using TFTs, and also to control gradation by voltage modulation, so that high-definition and high-quality display is possible. This is because it can be realized.
　なお、「単安定性を示す」とは、電圧無印加時の液晶分子の状態がひとつの状態で安定化している状態をいう。強誘電性液晶組成物は、図１０に例示するように、液晶分子２５が層法線ｚから傾いており、層法線ｚに垂直な底面を有する円錐（コーン）の稜線に沿って回転する。このような円錐（コーン）において、液晶分子２５の層法線ｚに対する傾き角をチルト角θという。このように、液晶分子２５は層法線ｚに対しチルト角±θだけ傾く二つの状態間をコーン上に動作することができる。具体的に説明すると、単安定性を示すとは、電圧無印加時に液晶分子２５がコーン上のいずれかひとつの状態で安定化している状態をいう。 In addition, “showing monostability” means a state where the state of liquid crystal molecules when no voltage is applied is stabilized in one state. In the ferroelectric liquid crystal composition, as illustrated in FIG. 10, the liquid crystal molecules 25 are tilted from the layer normal z and rotate along a cone ridge having a bottom surface perpendicular to the layer normal z. . In such a cone, the tilt angle of the liquid crystal molecules 25 with respect to the layer normal z is referred to as a tilt angle θ. Thus, the liquid crystal molecules 25 can operate on the cone between two states inclined by a tilt angle ± θ with respect to the layer normal z. Specifically, the expression of monostability refers to a state in which the liquid crystal molecules 25 are stabilized in any one state on the cone when no voltage is applied.
　また、強誘電性液晶組成物としては、単安定性を示すものであればよく、正負いずれかの電圧を印加したときのみ液晶分子が動作するハーフＶ字型スイッチング特性を示すもの、正負いずれの電圧に対しても同程度液晶分子が動作するＶ字型スイッチング特性を示すもの、正負いずれかの電圧に対する液晶分子の動作が他方の極性の電圧に対する液晶分子の動作に比べて大きくなる非対称のスイッチング特性を示すもの、のいずれも使用することができる。 In addition, the ferroelectric liquid crystal composition only needs to exhibit monostability, and exhibits a half V-shaped switching characteristic in which liquid crystal molecules operate only when a positive or negative voltage is applied. A V-shaped switching characteristic in which liquid crystal molecules operate to the same degree with respect to voltage, asymmetric switching in which the operation of liquid crystal molecules for either positive or negative voltage is larger than the operation of liquid crystal molecules for the other polarity voltage Any of those exhibiting properties can be used.
　中でも、図１１（ａ）、（ｂ）に例示するような、ハーフＶ字型スイッチング特性を示すものは、コーン角が比較的小さくても透過率を明るくすることができる。コーン角が十分大きい場合は、図１１（ｃ）に例示するようなＶ字型スイッチング特性にすることで、正負の電圧に対する液晶分子の動作が対称になり、電気的中性になり、安定性の点で好ましい。また、非対称のスイッチング特性であっても、駆動方法を工夫することで使用することができる。 Among them, those showing the half V-shaped switching characteristics as exemplified in FIGS. 11A and 11B can increase the transmittance even if the cone angle is relatively small. When the cone angle is sufficiently large, the V-shaped switching characteristics as illustrated in FIG. 11C make the operation of liquid crystal molecules symmetrical with respect to positive and negative voltages, electrical neutrality, and stability. This is preferable. Even asymmetric switching characteristics can be used by devising a driving method.
　このような強誘電性液晶組成物としては、一般に知られる液晶材料の中から要求特性に応じて種々選択することができる。特に、Ｃｈ相からＳｍＡ相を経由しないでＳｍＣ＊相を発現する強誘電性液晶組成物は、温度変化に対して、電圧に対する動作特性の変化が少ないことから好ましい。 Such a ferroelectric liquid crystal composition can be variously selected from generally known liquid crystal materials according to required characteristics. In particular, the ferroelectric liquid crystal composition that expresses the SmC * phase from the Ch phase without passing through the SmA phase is preferable because the change in the operating characteristics with respect to the voltage is small with respect to the temperature change.
　２．液晶層
　本発明における液晶層は、第１配向処理基板の第１配向膜および第２配向処理基板の第２配向膜の間に形成され、上述の強誘電性液晶組成物を含有するものである。 2. Liquid Crystal Layer The liquid crystal layer in the present invention is formed between the first alignment film of the first alignment treatment substrate and the second alignment film of the second alignment treatment substrate, and contains the above-described ferroelectric liquid crystal composition. .
　液晶層の厚みは、１．０μｍ～１０．０μｍの範囲内であることが好ましく、より好ましくは１．３μｍ～５．０μｍの範囲内、さらに好ましくは１．４μｍ～３．０μｍの範囲内である。液晶層の厚みが薄すぎるとコントラストが低下するおそれがあり、逆に液晶層の厚みが厚すぎると液晶分子が配向しにくくなる可能性があるからである。液晶層の厚みは、ビーズスペーサ、柱状スペーサ、隔壁等により調整することができる。 The thickness of the liquid crystal layer is preferably in the range of 1.0 μm to 10.0 μm, more preferably in the range of 1.3 μm to 5.0 μm, and still more preferably in the range of 1.4 μm to 3.0 μm. is there. This is because if the thickness of the liquid crystal layer is too thin, the contrast may be lowered. Conversely, if the thickness of the liquid crystal layer is too thick, the liquid crystal molecules may be difficult to align. The thickness of the liquid crystal layer can be adjusted by a bead spacer, a columnar spacer, a partition wall, or the like.
　液晶層の形成方法としては、一般に液晶セルの作製方法として用いられる方法を使用することができ、例えば真空注入方式、液晶滴下方式等を用いることができる。
　真空注入方式では、例えば、まず、あらかじめ第１配向処理基板および第２配向処理基板を用いて作製した液晶セルに、加温することによって等方性液体とした強誘電性液晶組成物を、キャピラリー効果を利用して注入する。次に、強誘電性液晶組成物が注入された液晶セルを、接着剤で封鎖することにより液晶層を形成することができる。
　また液晶滴下方式では、例えば、まず、第２配向処理基板の第２配向膜上に、加温したもしくは常温の強誘電性液晶組成物を滴下または塗布する。次いで、第１配向処理基板の周縁部にシール剤を塗布する。続いて、減圧下で第１配向処理基板および第２配向処理基板を重ね合わせ、シール剤を介して接着させることにより液晶層を形成することができる。 As a method for forming the liquid crystal layer, a method generally used as a method for manufacturing a liquid crystal cell can be used. For example, a vacuum injection method, a liquid crystal dropping method, or the like can be used.
In the vacuum injection method, for example, first, a ferroelectric liquid crystal composition made into an isotropic liquid by heating is applied to a liquid crystal cell that has been prepared using a first alignment treatment substrate and a second alignment treatment substrate in advance. Inject using the effect. Next, a liquid crystal layer can be formed by sealing the liquid crystal cell injected with the ferroelectric liquid crystal composition with an adhesive.
In the liquid crystal dropping method, for example, first, a heated or room temperature ferroelectric liquid crystal composition is dropped or applied onto the second alignment film of the second alignment processing substrate. Next, a sealant is applied to the peripheral portion of the first alignment processing substrate. Subsequently, a liquid crystal layer can be formed by stacking the first alignment treatment substrate and the second alignment treatment substrate under reduced pressure and bonding them with a sealant.
　中でも、液晶層の形成方法は、液晶滴下方式であることが好ましい。タクトタイムの短縮により、液晶表示素子を効率的に製造することができるからである。また、強誘電性液晶組成物を滴下または塗布する際には、常温とすることが好ましい。熱による強誘電性液晶組成物の劣化を防ぐことができるからである。 Among these, the liquid crystal layer forming method is preferably a liquid crystal dropping method. This is because the liquid crystal display element can be efficiently manufactured by shortening the tact time. In addition, when the ferroelectric liquid crystal composition is dropped or applied, it is preferably at room temperature. This is because deterioration of the ferroelectric liquid crystal composition due to heat can be prevented.
　強誘電性液晶組成物を配向させる際には、冷却すればよく、液晶層に電圧を印加する必要はない。冷却時には徐冷することが好ましい。 When aligning the ferroelectric liquid crystal composition, it may be cooled, and it is not necessary to apply a voltage to the liquid crystal layer. It is preferable to cool slowly during cooling.
　Ｃ．第１配向処理基板
　本発明に用いられる第１配向処理基板は、第１基材と、第１基材上に形成された第１電極層と、第１電極層上に形成された第１配向膜とを有するものである。
　なお、第１配向膜については、上述したので、ここでの説明は省略する。以下、第１配向処理基板における他の構成について説明する。 C. 1st orientation processing board The 1st orientation processing board used for the present invention is the 1st base material, the 1st electrode layer formed on the 1st base material, and the 1st orientation formed on the 1st electrode layer. And a film.
Since the first alignment film has been described above, the description thereof is omitted here. Hereinafter, another configuration of the first alignment processing substrate will be described.
　１．第１電極層
　本発明に用いられる第１電極層は、一般に液晶表示素子の電極として用いられているものであれば特に限定されるものではないが、第１配向処理基板の第１電極層および第２配向処理基板の第２電極層のうち少なくとも一方が透明導電体で形成されることが好ましい。透明導電体材料としては、酸化インジウム、酸化錫、酸化インジウム錫（ＩＴＯ）等が好ましく挙げられる。 1. 1st electrode layer Although the 1st electrode layer used for this invention will not be specifically limited if it is generally used as an electrode of a liquid crystal display element, The 1st electrode layer of a 1st orientation processing board | substrate and It is preferable that at least one of the second electrode layers of the second alignment treatment substrate is formed of a transparent conductor. Preferred examples of the transparent conductor material include indium oxide, tin oxide, indium tin oxide (ITO), and the like.
　本発明により得られる液晶表示素子を、ＴＦＴを用いたアクティブマトリックス方式で駆動させる場合には、第１配向処理基板および第２配向処理基板のうち、一方に上記透明導電体で形成される全面共通電極を設け、他方にはゲート電極とソース電極をマトリックス状に配列し、ゲート電極とソース電極で囲まれた部分にＴＦＴ素子および画素電極を設ける。 When the liquid crystal display element obtained by the present invention is driven by an active matrix system using TFTs, one of the first alignment processing substrate and the second alignment processing substrate is formed on the entire surface formed of the transparent conductor. An electrode is provided, and on the other side, a gate electrode and a source electrode are arranged in a matrix, and a TFT element and a pixel electrode are provided in a portion surrounded by the gate electrode and the source electrode.
　第１電極層の形成方法としては、化学蒸着（ＣＶＤ）法や、スパッタリング法、イオンプレーティング法、真空蒸着法等の物理蒸着（ＰＶＤ）法などが挙げられる。 Examples of the method for forming the first electrode layer include chemical vapor deposition (CVD), physical vapor deposition (PVD) such as sputtering, ion plating, and vacuum deposition.
　２．第１基材
　本発明に用いられる第１基材は、一般に液晶表示素子の基材として用いられるものであれば特に限定されるものではなく、例えば、ガラス板、プラスチック板などが好ましく挙げられる。 2. 1st base material The 1st base material used for this invention will not be specifically limited if generally used as a base material of a liquid crystal display element, For example, a glass plate, a plastic plate, etc. are mentioned preferably.
　３．その他の構成
　本発明おける第１配向処理基板においては、第１基材上に隔壁または柱状スペーサが形成されていてもよい。第２配向処理基板において第２基材上に隔壁または柱状スペーサが形成されている場合には、第１配向処理基板において第１基材上には隔壁または柱状スペーサが形成されない。すなわち、第１配向処理基板に隔壁または柱状スペーサが形成されていてもよく、第２配向処理基板に隔壁または柱状スペーサが形成されていてもよい。
　隔壁および柱状スペーサとしては、一般的な隔壁および柱状スペーサを適用することができる。 3. Other Configurations In the first alignment processing substrate in the present invention, a partition wall or a columnar spacer may be formed on the first base material. When the partition or columnar spacer is formed on the second base material in the second alignment processing substrate, the partition or columnar spacer is not formed on the first base material in the first alignment processing substrate. That is, partition walls or columnar spacers may be formed on the first alignment processing substrate, and partition walls or columnar spacers may be formed on the second alignment processing substrate.
As the partition walls and columnar spacers, general partition walls and columnar spacers can be applied.
　また、本発明における第１配向処理基板おいては、第１基材上に着色層が形成されていてもよい。第２配向処理基板において第２基材上に着色層が形成されている場合には、第１配向処理基板において第１基材上には着色層が形成されない。すなわち、第１配向処理基板に着色層が形成されていてもよく、第２配向処理基板に着色層が形成されていてもよい。
　着色層が形成されている場合には、着色層によってカラー表示を実現することができるカラーフィルタ方式の液晶表示素子を得ることができる。
　着色層の形成方法としては、一般的なカラーフィルタにおける着色層を形成する方法を用いることができ、例えば、顔料分散法（カラーレジスト法、エッチング法）、印刷法、インクジェット法などを用いることができる。 Moreover, in the 1st orientation processing board | substrate in this invention, the colored layer may be formed on the 1st base material. When the colored layer is formed on the second base material in the second alignment processing substrate, the coloring layer is not formed on the first base material in the first alignment processing substrate. That is, a colored layer may be formed on the first alignment processing substrate, and a coloring layer may be formed on the second alignment processing substrate.
When the colored layer is formed, a color filter type liquid crystal display element capable of realizing color display by the colored layer can be obtained.
As a method for forming the colored layer, a method for forming a colored layer in a general color filter can be used. For example, a pigment dispersion method (color resist method, etching method), a printing method, an inkjet method, or the like can be used. it can.
　Ｄ．第２配向処理基板
　本発明に用いられる第２配向処理基板は、第２基材と、第２基材上に形成された第２電極層と、第２電極層上に形成された第２配向膜とを有するものである。
　なお、第２配向膜については、上述したので、ここでの説明は省略する。また、第２基材、第２電極層、およびその他の構成については、上記第１配向処理基板における第１基材、第１電極層、およびその他の構成とそれぞれ同様であるので、ここでの説明は省略する。 D. Second alignment treatment substrate The second alignment treatment substrate used in the present invention includes a second base material, a second electrode layer formed on the second base material, and a second orientation formed on the second electrode layer. And a film.
Since the second alignment film has been described above, description thereof is omitted here. The second base material, the second electrode layer, and other configurations are the same as the first base material, the first electrode layer, and other configurations in the first alignment processing substrate, respectively. Description is omitted.
　Ｅ．その他の構成
　本発明の液晶表示素子は、偏光板を有していてもよい。
　本発明に用いられる偏光板としては、光の波動のうち特定方向のみを透過させるものであれば特に限定されるものではなく、一般に液晶表示素子の偏光板として用いられているものを使用することができる。 E. Other Configurations The liquid crystal display element of the present invention may have a polarizing plate.
The polarizing plate used in the present invention is not particularly limited as long as it transmits only a specific direction among the wave of light, and a polarizing plate generally used as a polarizing plate of a liquid crystal display element should be used. Can do.
　Ｆ．液晶表示素子の駆動方法
　本発明においては、強誘電性液晶組成物が単安定性を示す場合であって、第１配向膜と第２配向膜とで、第２配向膜の方が相対的に正の極性が強い傾向にある場合、第２電極層に負の電圧を印加したときに、表示を行うことが好ましい。 F. In the present invention, the ferroelectric liquid crystal composition exhibits monostability, and the second alignment film is relatively the first alignment film and the second alignment film. When the positive polarity tends to be strong, display is preferably performed when a negative voltage is applied to the second electrode layer.
　図１２は、単安定性を示し、ハーフＶ字型のスイッチング特性を示す液晶分子の配向状態の一例を示す模式図である。図１２（ａ）は電圧無印加の場合、図１２（ｂ）は第２電極層に負の電圧を印加した場合、図１２（ｃ）は第２電極層に正の電圧を印加した場合をそれぞれ示す。電圧無印加の場合、液晶分子２５は、コーン上のひとつの状態で安定化している（図１２（ａ））。第２電極層に負の電圧を印加した場合、液晶分子２５は、安定化している状態（破線）から一方の側に傾く（図１２（ｂ））。また、第２電極層に正の電圧を印加したときに、液晶分子２５は、安定化している状態（破線）から第２電極層に負の電圧を印加したときとは逆側に傾く（図１２（ｃ））。このとき、第２電極層に負の電圧を印加したときの傾斜角δは、第２電極層に正の電圧を印加したときの傾斜角ωよりも大きい。なお、図９において、Ｄ１，Ｄ２はそれぞれ第１配向膜および第２配向膜のラビング処理方向、ｚは層法線を示す。 FIG. 12 is a schematic diagram showing an example of an alignment state of liquid crystal molecules showing monostability and showing half V-shaped switching characteristics. 12A shows a case where no voltage is applied, FIG. 12B shows a case where a negative voltage is applied to the second electrode layer, and FIG. 12C shows a case where a positive voltage is applied to the second electrode layer. Each is shown. When no voltage is applied, the liquid crystal molecules 25 are stabilized in one state on the cone (FIG. 12A). When a negative voltage is applied to the second electrode layer, the liquid crystal molecules 25 are tilted from the stabilized state (broken line) to one side (FIG. 12B). In addition, when a positive voltage is applied to the second electrode layer, the liquid crystal molecules 25 are tilted from the stabilized state (broken line) to the opposite side when a negative voltage is applied to the second electrode layer (see FIG. 12 (c)). At this time, the inclination angle δ when a negative voltage is applied to the second electrode layer is larger than the inclination angle ω when a positive voltage is applied to the second electrode layer. In FIG. 9, D1 and D2 are the rubbing treatment directions of the first alignment film and the second alignment film, respectively, and z is the layer normal.
　このように第２配向膜の方が相対的に正の極性が強い傾向にある場合には、第２電極層の負の電圧を印加したときの液晶分子の単安定化状態からの傾斜角が、第２電極層の正の電圧を印加したときの液晶分子の単安定化状態からの傾斜角よりも大きくなる。したがって、第２電極層の負の電圧を印加したときは、第２電極層に正の電圧を印加したときよりも、透過光量が多くなる。すなわち、第２電極層の正の電圧を印加したときは、第２電極層に負の電圧を印加したときよりも、透過光量が少なくなる。そのため、第２電極層の正の電圧を印加したときは、第２電極層に負の電圧を印加したときよりも、表示に不利となる。よって、液晶分子の単安定化状態からの傾斜角がより大きくなる、第２電極層に負の電圧を印加したときに、表示を行うことが好ましいのである。 In this way, when the second alignment film tends to have a relatively positive polarity, the inclination angle of the liquid crystal molecules from the mono-stabilized state when the negative voltage of the second electrode layer is applied is When the positive voltage of the second electrode layer is applied, the inclination angle of the liquid crystal molecules from the mono-stabilized state becomes larger. Therefore, when a negative voltage is applied to the second electrode layer, the amount of transmitted light is larger than when a positive voltage is applied to the second electrode layer. That is, when a positive voltage is applied to the second electrode layer, the amount of transmitted light is less than when a negative voltage is applied to the second electrode layer. For this reason, when a positive voltage is applied to the second electrode layer, it is more disadvantageous for display than when a negative voltage is applied to the second electrode layer. Therefore, it is preferable to perform display when a negative voltage is applied to the second electrode layer where the tilt angle from the mono-stabilized state of the liquid crystal molecules becomes larger.
　なお、「第２電極層に負の電圧を印加したときに、表示を行う」とは、電圧無印加時に液晶分子がコーン上のひとつの状態で安定化しており、第２電極層に負の電圧を印加したときに、液晶分子が単安定化状態からコーン上の一方の側に傾き、第２電極層に正の電圧を印加したときに、液晶分子が、単安定化状態を維持するか、または単安定化状態から第２電極層に負の電圧を印加したときとは逆側に傾き、第２電極層に負の電圧を印加したときの、液晶分子の単安定化状態からの傾斜角が、第２電極層に正の電圧を印加したときの、液晶分子の単安定化状態からの傾斜角よりも大きいことをいう。このとき、液晶分子の単安定化状態での配向方向と一方の偏光板の偏光軸とは略平行にされる。 “Display when a negative voltage is applied to the second electrode layer” means that liquid crystal molecules are stabilized in one state on the cone when no voltage is applied, and the second electrode layer is negative. When the voltage is applied, the liquid crystal molecules tilt from the mono-stabilized state to one side on the cone, and the liquid crystal molecules maintain the mono-stabilized state when a positive voltage is applied to the second electrode layer. Or tilted from the mono-stabilized state to the opposite side of the negative voltage applied to the second electrode layer, and tilted from the mono-stabilized state of the liquid crystal molecules when a negative voltage is applied to the second electrode layer. It means that the angle is larger than the tilt angle from the mono-stabilized state of the liquid crystal molecules when a positive voltage is applied to the second electrode layer. At this time, the alignment direction in the mono-stabilized state of the liquid crystal molecules and the polarization axis of one polarizing plate are made substantially parallel.
　第１配向膜と第２配向膜とで、第２配向膜の方が相対的に正の極性が強い傾向にある場合、電圧無印加状態では、図８に例示するように、極性表面相互作用によって、液晶分子２５の自発分極Ｐｓが第１配向膜４ａ側を向く傾向にある。このとき、図１３（ａ）に例示するように液晶分子２５が第１配向膜および第２配向膜の配向処理方向Ｄ１、Ｄ２に沿って配向し、一様な配向状態となる。また、第２電極層３ｂに負の電圧を印加すると、図９に例示するように、印加電圧の極性の影響により、液晶分子２５の自発分極Ｐｓは第２配向膜４ｂ側を向くようになる。このときも、図１３（ｂ）に例示するように液晶分子２５は一様な配向状態となる。さらに、第２電極層３ｂに正の電圧を印加すると、図８に例示するように、印加電圧の極性の影響によって、液晶分子２５の自発分極Ｐｓは第１配向膜４ａ側を向くようになる。この場合、自発分極の向きは、電圧無印加状態と同様になる。自発分極の向きがこのような方向になるのは、上述したように、自発分極の向きが、液晶分子の分極と配向膜の分極または電圧の極性とが電気的につり合う方向になり、液晶分子が電気的に安定な状態になるためである。
　なお、図１３（ａ）は、図８の上面からの液晶分子の配向状態を示す模式図であり、自発分極Ｐｓは紙面手前から奥方向に向いている（図１３（ａ）中の×印）。また、図１３（ｂ）は、図９の上面からの液晶分子の配向状態を示す模式図であり、自発分極Ｐｓは紙面奥から手前方向に向いている（図１３（ｂ）中の●印）。 When the first alignment film and the second alignment film tend to have a relatively positive polarity in the second alignment film, in the no voltage applied state, as illustrated in FIG. Therefore, the spontaneous polarization Ps of the liquid crystal molecules 25 tends to face the first alignment film 4a side. At this time, as illustrated in FIG. 13A, the liquid crystal molecules 25 are aligned along the alignment treatment directions D1 and D2 of the first alignment film and the second alignment film, thereby obtaining a uniform alignment state. Further, when a negative voltage is applied to the second electrode layer 3b, the spontaneous polarization Ps of the liquid crystal molecules 25 is directed to the second alignment film 4b side due to the influence of the polarity of the applied voltage, as illustrated in FIG. . Also at this time, the liquid crystal molecules 25 are in a uniform alignment state as illustrated in FIG. Furthermore, when a positive voltage is applied to the second electrode layer 3b, the spontaneous polarization Ps of the liquid crystal molecules 25 is directed toward the first alignment film 4a due to the influence of the polarity of the applied voltage, as illustrated in FIG. . In this case, the direction of spontaneous polarization is the same as that in the state where no voltage is applied. As described above, the direction of the spontaneous polarization is the direction in which the polarization of the liquid crystal molecules and the polarization of the alignment film or the polarity of the voltage are electrically balanced. This is because of an electrically stable state.
FIG. 13A is a schematic diagram showing the alignment state of the liquid crystal molecules from the upper surface of FIG. 8, and the spontaneous polarization Ps is directed from the front side to the back side of the drawing (the mark “X” in FIG. 13A). ). FIG. 13B is a schematic diagram showing the alignment state of the liquid crystal molecules from the upper surface of FIG. 9, and the spontaneous polarization Ps is directed from the back of the page to the near side (the mark ● in FIG. 13B). ).
　電圧無印加状態あるいは第２電極層への正の電圧印加状態（図８）から、第２電極層への負の電圧印加状態（図９）としたとき、この印加電圧の負の極性と、液晶分子の自発分極の負の極性との反発によって、図１４に例示するように、液晶分子２５が角度約２θ回転する。すなわち、第２電極層に負の電圧を印加したときに、液晶の分子方向が、第１配向処理基板面に対して平行に、液晶分子のチルト角θの約２倍変化する。 When no voltage is applied or when a positive voltage is applied to the second electrode layer (FIG. 8), a negative voltage is applied to the second electrode layer (FIG. 9). Due to the repulsion of the spontaneous polarization of the liquid crystal molecules with the negative polarity, the liquid crystal molecules 25 rotate by about 2θ as illustrated in FIG. That is, when a negative voltage is applied to the second electrode layer, the molecular direction of the liquid crystal changes approximately twice the tilt angle θ of the liquid crystal molecules in parallel to the first alignment treatment substrate surface.
　このように、第１配向膜と第２配向膜とで第２配向膜の方が相対的に正の極性が強い傾向にある場合、第１配向膜側に液晶分子の自発分極が向く傾向にあることを利用して、液晶分子の自発分極の向きを制御することが可能である。 Thus, when the second alignment film tends to have a relatively positive polarity between the first alignment film and the second alignment film, the spontaneous polarization of the liquid crystal molecules tends to be directed to the first alignment film side. By utilizing this, it is possible to control the direction of spontaneous polarization of liquid crystal molecules.
　なお、Ｖ字型スイッチング特性や非対称のスイッチング特性を示す強誘電性液晶組成物を用いた液晶表示素子においても、同様に液晶分子の自発分極の向きを制御することで駆動することが可能である。 A liquid crystal display element using a ferroelectric liquid crystal composition exhibiting V-shaped switching characteristics or asymmetric switching characteristics can be driven by controlling the direction of spontaneous polarization of liquid crystal molecules in the same manner. .
　第２電極層に負の電圧を印加したとき、液晶の分子方向がチルト角の約２倍変化するものは７０％以上存在することが好ましく、より好ましくは８０％以上、さらに好ましくは９０％以上、最も好ましくは９５％以上である。上記範囲であれば、良好なコントラスト比を得ることができるからである。 When a negative voltage is applied to the second electrode layer, there are preferably 70% or more, more preferably 80% or more, more preferably 90% or more, in which the molecular direction of the liquid crystal changes about twice the tilt angle. Most preferably, it is 95% or more. This is because a favorable contrast ratio can be obtained within the above range.
　なお、上記の比率は、次のようにして測定することができる。
　例えば図１５に示すような、第１配向処理基板１１ａおよび第２配向処理基板１１ｂの外側にそれぞれ偏光板１７ａ、１７ｂが設けられ、２枚の偏光板１７ａ、１７ｂがそれぞれの偏光軸が略垂直に、かつ、偏光板１７ａの偏光軸と第１配向膜４ａのラビング処理方向（液晶分子の配向方向）とが略平行になるように配置された液晶表示素子を用いる。電圧無印加状態では暗状態、電圧印加状態では明状態となる。
　第２電極層に負の電圧を印加したとき、液晶の分子方向がチルト角の約２倍変化すると明状態が得られる。一方、第２電極層に負の電圧を印加したとき、例えば液晶の分子方向が変化しないものが部分的に存在する場合には、部分的に暗状態が得られる。したがって、電圧印加時に得られる白黒（明暗）表示の白・黒の面積比から、第２電極層に負の電圧を印加したときに液晶の分子方向がチルト角の約２倍変化するものの比率を算出することができる。 In addition, said ratio can be measured as follows.
For example, as shown in FIG. 15, polarizing plates 17a and 17b are provided on the outer sides of the first alignment processing substrate 11a and the second alignment processing substrate 11b, respectively, and the two polarizing plates 17a and 17b have substantially vertical polarization axes. In addition, a liquid crystal display element is used in which the polarization axis of the polarizing plate 17a and the rubbing treatment direction (the alignment direction of liquid crystal molecules) of the first alignment film 4a are substantially parallel. A dark state is obtained when no voltage is applied, and a bright state is obtained when a voltage is applied.
When a negative voltage is applied to the second electrode layer, a bright state is obtained when the molecular direction of the liquid crystal changes approximately twice the tilt angle. On the other hand, when a negative voltage is applied to the second electrode layer, for example, when there is a part in which the molecular direction of the liquid crystal does not change, a dark state is partially obtained. Therefore, from the white / black area ratio of black and white (light / dark) display obtained at the time of voltage application, the ratio of the liquid crystal molecular direction changing about twice the tilt angle when a negative voltage is applied to the second electrode layer. Can be calculated.
　第２電極層に負の電圧を印加したとき、液晶分子は、印加電圧の大きさに応じた角度で、単安定化状態からコーン上の一方の側に傾く。また、強誘電性液晶では、図１２（ａ）に例示するように、位置Ａ（液晶分子２５の方向）と、位置Ｂ（ラビング処理方向Ｄ１，Ｄ２）と、位置Ｃとが、必ずしも一致するわけではない。そのため、図１２（ｂ）に例示するように、第２電極層に負の電圧を印加したときの最大の傾斜角δは、チルト角θの約２倍となる。 When a negative voltage is applied to the second electrode layer, the liquid crystal molecules are inclined from the mono-stabilized state to one side on the cone at an angle corresponding to the magnitude of the applied voltage. Further, in the ferroelectric liquid crystal, as illustrated in FIG. 12A, the position A (direction of the liquid crystal molecules 25), the position B (rubbing treatment directions D1, D2), and the position C are not necessarily coincident. Do not mean. Therefore, as illustrated in FIG. 12B, the maximum tilt angle δ when a negative voltage is applied to the second electrode layer is about twice the tilt angle θ.
　なお、液晶の分子方向が第１配向処理基板面に対して平行に変化した角度は、次のようにして測定することができる。まず、偏光板をクロスニコルに配置した偏光顕微鏡および液晶表示素子を、一方の偏光板の偏光軸と液晶層の液晶分子の配向方向とが平行になるように配置し、この位置を基準とする。電圧を印加すると液晶分子が偏光軸と所定の角度を持つようになるため、一方の偏光板を透過した偏光が他方の偏光板を透過して明状態となる。この電圧を印加した状態で液晶表示素子を回転させ暗状態にする。そして、このときの液晶表示素子を回転させた角度を測定する。液晶表示素子を回転させた角度が、液晶の分子方向が第１配向処理基板面に対して平行に変化した角度である。 It should be noted that the angle at which the molecular direction of the liquid crystal changes parallel to the first alignment treatment substrate surface can be measured as follows. First, a polarizing microscope and a liquid crystal display element in which polarizing plates are arranged in crossed Nicols are arranged so that the polarization axis of one polarizing plate and the alignment direction of liquid crystal molecules in the liquid crystal layer are parallel, and this position is used as a reference. . When a voltage is applied, the liquid crystal molecules come to have a predetermined angle with the polarization axis, so that the polarized light transmitted through one polarizing plate is transmitted through the other polarizing plate to be in a bright state. With this voltage applied, the liquid crystal display element is rotated to a dark state. And the angle which rotated the liquid crystal display element at this time is measured. The angle by which the liquid crystal display element is rotated is an angle at which the molecular direction of the liquid crystal changes in parallel to the first alignment processing substrate surface.
　上述したように、第２電極層に負の電圧を印加したとき、液晶分子は、印加電圧の大きさに応じた角度で、単安定化状態からコーン上の一方の側に傾くので、実際に液晶表示素子を駆動している際、第２電極層に負の電圧を印加したときに、液晶分子の方向がチルト角の約２倍変化するわけではない。 As described above, when a negative voltage is applied to the second electrode layer, the liquid crystal molecules are inclined from the mono-stabilized state to one side on the cone at an angle according to the magnitude of the applied voltage. When driving the liquid crystal display element, the direction of the liquid crystal molecules does not change about twice the tilt angle when a negative voltage is applied to the second electrode layer.
　単安定性を示す強誘電性液晶組成物を用いた液晶表示素子においては、透過光量は、電圧を印加したときの液晶分子の傾斜角に依存する。正負いずれかの電圧を印加すると液晶分子がコーン上を傾くので、例えば図１１に示すように印加電圧の大きさに応じて液晶分子の傾斜角が変化して透過光量が変化する。このとき、液晶分子の単安定状態からの傾斜角が４５°の場合に透過光量が最大になる。
　したがって、高い透過光量を実現するためには、実際の駆動時に第２電極層に負の電圧を印加した場合に、液晶分子の単安定状態からの傾斜角が４５°になり得る強誘電性液晶組成物を用いることが好ましい。
　例えば、図１２に示すような液晶分子の単安定状態からの最大の傾斜角δが４５°よりも大きい強誘電性液晶組成物を用いた場合には、実際に液晶表示素子を駆動している際、第２電極層に負の電圧を印加したときに、液晶分子の単安定状態からの傾斜角を４５°とすることができる。上述したように、実際の駆動時に第２電極層に負の電圧を印加した場合に、液晶分子の方向がチルト角の約２倍変化するわけではないからである。 In a liquid crystal display element using a ferroelectric liquid crystal composition exhibiting monostability, the amount of transmitted light depends on the tilt angle of liquid crystal molecules when a voltage is applied. When either positive or negative voltage is applied, the liquid crystal molecules are tilted on the cone, so that, for example, as shown in FIG. At this time, the amount of transmitted light is maximized when the inclination angle of the liquid crystal molecules from the monostable state is 45 °.
Therefore, in order to realize a high amount of transmitted light, a ferroelectric liquid crystal whose tilt angle from a monostable state of liquid crystal molecules can be 45 ° when a negative voltage is applied to the second electrode layer during actual driving. It is preferable to use a composition.
For example, when a ferroelectric liquid crystal composition having a maximum tilt angle δ from a monostable state of liquid crystal molecules as shown in FIG. 12 is larger than 45 °, the liquid crystal display element is actually driven. At this time, when a negative voltage is applied to the second electrode layer, the tilt angle of the liquid crystal molecules from the monostable state can be set to 45 °. This is because, as described above, when a negative voltage is applied to the second electrode layer during actual driving, the direction of the liquid crystal molecules does not change approximately twice the tilt angle.
　本発明の液晶表示素子の駆動方法としては、強誘電性液晶組成物の高速応答性を利用することができるので、１画素を時間分割し、良好な動画表示特性を得るために高速応答性を特に必要とするフィールドシーケンシャルカラー方式にも好適に用いることができる。 As the driving method of the liquid crystal display element of the present invention, the high-speed response of the ferroelectric liquid crystal composition can be used. In particular, it can be suitably used for a required field sequential color system.
　また、本発明の液晶表示素子の駆動方法は、フィールドシーケンシャル方式に限定されるものではなく、着色層を用いてカラー表示を行う、カラーフィルタ方式であってもよい。 The driving method of the liquid crystal display element of the present invention is not limited to the field sequential method, and may be a color filter method that performs color display using a colored layer.
　本発明の液晶表示素子の駆動方法としては、薄膜トランジスタ（ＴＦＴ）を用いたアクティブマトリックス方式が好ましい。ＴＦＴを用いたアクティブマトリックス方式を採用することにより、目的の画素を確実に点灯、消灯できるため高品質なディスプレイが可能となるからである。 As a driving method of the liquid crystal display element of the present invention, an active matrix method using a thin film transistor (TFT) is preferable. This is because by adopting an active matrix system using TFTs, the target pixel can be reliably turned on and off, and a high-quality display becomes possible.
　本発明においては、第１配向処理基板がＴＦＴ基板、第２配向処理基板が共通電極基板であってもよく、第１配向処理基板が共通電極基板、第２配向処理基板がＴＦＴ基板であってもよい。中でも、第１配向膜と第２配向膜とで、第２配向膜の方が相対的に正の極性が強い傾向にある場合、第１配向処理基板がＴＦＴ基板、第２配向処理基板が共通電極基板であることが好ましい。 In the present invention, the first alignment treatment substrate may be a TFT substrate, the second alignment treatment substrate may be a common electrode substrate, the first alignment treatment substrate is a common electrode substrate, and the second alignment treatment substrate is a TFT substrate. Also good. In particular, when the first alignment film and the second alignment film tend to have a relatively positive polarity in the second alignment film, the first alignment process substrate is common to the TFT substrate and the second alignment process substrate. An electrode substrate is preferred.
　例えば図１６に示す液晶表示素子１において、ゲート電極２６ｘを３０Ｖ程度の高電位にするとＴＦＴ素子２７のスイッチがオンになり、ソース電極２６ｙによって信号電圧が強誘電性液晶組成物に加えられ、ゲート電極２６ｘを－１０Ｖ程度の低電位にするとＴＦＴ素子２７のスイッチがオフになる。スイッチオフ状態では、図１６に例示するように、共通電極（第２電極層３ｂ）およびゲート電極２６ｘ間には、共通電極（第２電極層３ｂ）側が正になるように電圧が印加される。このスイッチオフ状態のとき、液晶分子は動作しないので、その画素は暗状態となる。 For example, in the liquid crystal display element 1 shown in FIG. 16, when the gate electrode 26x is set to a high potential of about 30V, the TFT element 27 is switched on, and the signal voltage is applied to the ferroelectric liquid crystal composition by the source electrode 26y. When the electrode 26x is set to a low potential of about −10V, the TFT element 27 is switched off. In the switch-off state, as illustrated in FIG. 16, a voltage is applied between the common electrode (second electrode layer 3b) and the gate electrode 26x so that the common electrode (second electrode layer 3b) side is positive. . In this switch-off state, the liquid crystal molecules do not operate, so that the pixel is in a dark state.
　第１配向膜と第２配向膜とで、第２配向膜の方が相対的に正の極性が強い傾向にある場合、電圧無印加状態では、極性表面相互作用によって液晶分子の自発分極が第１配向膜側を向く傾向にある。すなわち、スイッチオフ状態のとき、図１７に例示するように、液晶分子２５の自発分極ＰｓがＴＦＴ基板（第１配向処理基板１１ａ）側を向く。したがって、自発分極の向きは、共通電極（第２電極層３ｂ）およびゲート電極２６ｘ間に印加された電圧の影響を受けることがない。よって、自発分極の向きを制御し、第１配向処理基板をＴＦＴ基板、第２配向処理基板を共通電極基板とすることにより、ゲート電極付近の光漏れを防止することができる。 In the first alignment film and the second alignment film, when the second alignment film tends to have a relatively strong positive polarity, the spontaneous polarization of the liquid crystal molecules is caused by the polar surface interaction in the no voltage applied state. There is a tendency to face one alignment film side. That is, in the switch-off state, as illustrated in FIG. 17, the spontaneous polarization Ps of the liquid crystal molecules 25 faces the TFT substrate (first alignment processing substrate 11a) side. Therefore, the direction of spontaneous polarization is not affected by the voltage applied between the common electrode (second electrode layer 3b) and the gate electrode 26x. Therefore, by controlling the direction of spontaneous polarization and using the first alignment processing substrate as the TFT substrate and the second alignment processing substrate as the common electrode substrate, light leakage near the gate electrode can be prevented.
　また、本発明の液晶表示素子の駆動方法は、セグメント方式であってもよい。 Further, the driving method of the liquid crystal display element of the present invention may be a segment method.
　なお、本発明は、上記実施形態に限定されるものではない。上記実施形態は、例示であり、本発明の特許請求の範囲に記載された技術的思想と実質的に同一な構成を有し、同様な作用効果を奏するものは、いかなるものであっても本発明の技術的範囲に包含される。 Note that the present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.
　以下に実施例および比較例を示し、本発明をさらに詳細に説明する。 Hereinafter, examples and comparative examples will be shown to describe the present invention in more detail.
　［実施例１］
　（強誘電性液晶組成物）
　下記に示すキラル化合物Ａのａ～ｂおよびキラル化合物Ｂの１～２を用い、下記表１に示すように強誘電性液晶組成物を準備した。 [Example 1]
(Ferroelectric liquid crystal composition)
Ferroelectric liquid crystal compositions were prepared as shown in Table 1 below using ab of chiral compound A and 1-2 of chiral compound B shown below.
Figure JPOXMLDOC01-appb-C000022
Figure JPOXMLDOC01-appb-C000022
Figure JPOXMLDOC01-appb-T000023
Figure JPOXMLDOC01-appb-T000023
　（液晶表示素子の作製）
　まず、ＩＴＯコーティングされたガラス基板上にΦ５．０μｍの円状で、高さ２．５μｍの樹脂スペーサを０．１ｍｍピッチで形成した。次いで、その上にラビング配向膜材料（ＳＥ６１０：日産化学工業株式会社）を回転数１５００ｒｐｍで３０秒間スピンコーティングした。その後、オーブンで１８０℃、３０分間乾燥後、ラビング処理を行った。
　次に、基板上に四角い枠状にシール材を塗布した。その基板上に、上述の強誘電性液晶組成物を点状に塗布し、二つの基板をラビング処理の方向が平行かつパラレルもしくはアンチパラレルになるように組み立て熱圧着を行った。その後、液晶セルを冷却し、強誘電性液晶組成物を配向させた。 (Production of liquid crystal display element)
First, resin spacers having a circular shape of Φ5.0 μm and a height of 2.5 μm were formed on an ITO-coated glass substrate at a pitch of 0.1 mm. Subsequently, a rubbing alignment film material (SE610: Nissan Chemical Industries, Ltd.) was spin-coated at a rotation speed of 1500 rpm for 30 seconds. Thereafter, the substrate was dried in an oven at 180 ° C. for 30 minutes, and then rubbed.
Next, a sealing material was applied in a square frame shape on the substrate. On the substrate, the above-mentioned ferroelectric liquid crystal composition was applied in the form of dots, and the two substrates were assembled and thermocompression bonded so that the rubbing treatment direction was parallel and parallel or antiparallel. Thereafter, the liquid crystal cell was cooled to align the ferroelectric liquid crystal composition.
　（評価）
　得られた液晶表示素子を観察し、図１８（ａ）に例示するように消光位が異なるドメインが発生した場合は「×」、図１８（ｂ）に例示するように消光位が異なるドメインが発生しなかった場合は「○」と評価した。 (Evaluation)
When the obtained liquid crystal display element is observed and a domain having a different extinction position is generated as illustrated in FIG. 18A, “x” is generated, and a domain having a different extinction position is illustrated in FIG. 18B. When it did not occur, it was evaluated as “◯”.
Figure JPOXMLDOC01-appb-T000024
Figure JPOXMLDOC01-appb-T000024
　［実施例２］
　（強誘電性液晶組成物）
　下記表３に示すキラル化合物Ａのｃ～ｈおよびキラル化合物Ｂの３～８を用いたこと以外は、実施例１と同様にして強誘電性液晶組成物を準備した。キラル化合物の合計含有量が１５質量％の場合、ホスト液晶I～IIIの各含有量は２８．３質量％とした。なお、右旋性を（＋）、左旋性を（－）で示す。 [Example 2]
(Ferroelectric liquid crystal composition)
A ferroelectric liquid crystal composition was prepared in the same manner as in Example 1 except that c to h of chiral compound A and 3 to 8 of chiral compound B shown in Table 3 were used. When the total content of chiral compounds was 15% by mass, the content of each of the host liquid crystals I to III was 28.3% by mass. The dextrorotatory property is indicated by (+) and the levorotatory property is indicated by (−).
Figure JPOXMLDOC01-appb-T000025
Figure JPOXMLDOC01-appb-T000025
　（液晶表示素子の作製）
　実施例１と同様にして液晶表示素子を作製した。 (Production of liquid crystal display element)
A liquid crystal display element was produced in the same manner as in Example 1.
　（評価）
　１）配向
　実施例１と同様に評価した。
　２）チルト角
　液晶分子の動いた角度は、偏光顕微鏡にて測定した。クロスニコルの状態に設定した２枚の偏光板の間に、強誘電性液晶組成物が充填された液晶セルを置き、電圧無印加状態の黒表示の位置を基準とし、正電圧（＋１０Ｖ）および負電圧（－１０Ｖ）印加時に動いた液晶分子の角度を測定した。ここでは、正電圧印加時に液晶分子が動いた角度と負電圧印加時に液晶分子が動いた角度の合計をチルト角とした。
　測定の結果、強誘電性液晶組成物に含有されるキラル化合物が置換基に２つのフッ素原子を有さない場合に比べて、強誘電性液晶組成物に含有されるキラル化合物のうち、いずれかのキラル化合物が置換基に２つのフッ素原子を有する場合にチルト角が大きくなった。また、強誘電性液晶組成物に含有されるキラル化合物のうち、いずれかのキラル化合物が置換基に２つのフッ素原子を有する場合に比べて、強誘電性液晶組成物に含有されるキラル化合物のいずれもが置換基に２つのフッ素原子を有する場合にチルト角がより大きくなった。
　３）透過率
　液晶表示素子の透過率を測定した。
　なお透過率は、チルト角より算出しており、チルト角が４５度のときの透過率を１００％とした場合の値である。また、この値は正電圧（＋１０Ｖ）印加時の透過率および負電圧（－１０Ｖ）印加時の透過率の平均値である。
　測定の結果、上述したチルト角の大きさに伴って透過率も高くなり、上記チルト角と同様の傾向が得られた。
　配向、チルト角および透過率の評価結果を表４および表５に示す。 (Evaluation)
1) Orientation Evaluation was performed in the same manner as in Example 1.
2) Tilt angle The angle at which the liquid crystal molecules moved was measured with a polarizing microscope. A liquid crystal cell filled with a ferroelectric liquid crystal composition is placed between two polarizing plates set in a crossed Nicol state, and the positive voltage (+10 V) and negative voltage are based on the position of black display when no voltage is applied. The angle of liquid crystal molecules that moved when (-10 V) was applied was measured. Here, the tilt angle is the sum of the angle of movement of the liquid crystal molecules when a positive voltage is applied and the angle of movement of the liquid crystal molecules when a negative voltage is applied.
As a result of the measurement, either of the chiral compounds contained in the ferroelectric liquid crystal composition is compared with the case where the chiral compound contained in the ferroelectric liquid crystal composition does not have two fluorine atoms in the substituent. The tilt angle was increased when this chiral compound had two fluorine atoms in the substituent. Further, among the chiral compounds contained in the ferroelectric liquid crystal composition, the chiral compound contained in the ferroelectric liquid crystal composition is compared with the case where any one of the chiral compounds has two fluorine atoms in the substituent. In any case, the tilt angle was larger when the substituent had two fluorine atoms.
3) Transmittance The transmittance of the liquid crystal display element was measured.
The transmittance is calculated from the tilt angle, and is a value when the transmittance when the tilt angle is 45 degrees is 100%. This value is an average value of transmittance when a positive voltage (+10 V) is applied and transmittance when a negative voltage (−10 V) is applied.
As a result of the measurement, the transmittance increased with the above-described tilt angle, and the same tendency as the tilt angle was obtained.
Tables 4 and 5 show the evaluation results of orientation, tilt angle, and transmittance.
Figure JPOXMLDOC01-appb-T000026
Figure JPOXMLDOC01-appb-T000026
Figure JPOXMLDOC01-appb-T000027
Figure JPOXMLDOC01-appb-T000027
　１　…　液晶表示素子
　２ａ　…　第１基材
　２ｂ　…　第２基材
　３ａ　…　第１電極層
　３ｂ　…　第２電極層
　４ａ　…　第１配向膜
　４ｂ　…　第２配向膜
　５　…　液晶層
　１１ａ　…　第１配向処理基板
　１１ｂ　…　第２配向処理基板
　２５　…　液晶分子
　Ｄ１、Ｄ２　…　ラビング処理方向
　Ｐｓ　…　自発分極
　ｚ　…　層法線 DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display element 2a ... 1st base material 2b ... 2nd base material 3a ... 1st electrode layer 3b ... 2nd electrode layer 4a ... 1st orientation film 4b ... 2nd orientation film 5 ... Liquid crystal layer 11a ... 1st orientation Processing substrate 11b ... Second alignment processing substrate 25 ... Liquid crystal molecules D1, D2 ... Rubbing processing direction Ps ... Spontaneous polarization z ... Layer normal

Claims (2)

  1. 　第１基材、前記第１基材上に形成された第１電極層、および、前記第１電極層上に形成され、ラビング処理された第１配向膜を有する第１配向処理基板と、
    　第２基材、前記第２基材上に形成された第２電極層、および、前記第２電極層上に形成され、ラビング処理された第２配向膜を有する第２配向処理基板と、
    　前記第１配向膜および前記第２配向膜の間に形成され、強誘電性液晶組成物を含む液晶層とを有する液晶表示素子であって、
    　前記第１配向膜および前記第２配向膜はラビング処理方向がパラレルとなるように配置されており、
    　前記強誘電性液晶組成物は、下記一般式（１）で表されるキラル化合物Ａおよび下記一般式（２）で表されるキラル化合物Ｂの少なくともいずれかのキラル化合物を含有することを特徴とする液晶表示素子。
    Figure JPOXMLDOC01-appb-C000001
     （上記式（１）において、Ｒ1は、非キラルな基であり、ハロゲン原子で置換されていてもよい炭素数４～１８の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
    Ｒ２は、キラルな基であり、下記一般式（３）で表される基である。
    Figure JPOXMLDOC01-appb-C000002
     （上記式（３）において、Ｒ３は、ハロゲン原子で置換されていてもよい炭素数１～１０の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
    Ｙ１は、－ＣＨ３またはフッ素原子を表す。ｍは０または１である。ｎは０または１である。＊印はキラル中心を示す。）
    Ｘ１～Ｘ８は、それぞれ独立して－ＣＨ３、－ＣＦ３、ハロゲン原子または水素原子を表す。ただし、Ｘ１～Ｘ８のうち１つ以上は、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子である。）
    Figure JPOXMLDOC01-appb-C000003
     （上記式（２）において、Ｒ４は、非キラルな基であり、ハロゲン原子で置換されていてもよい炭素数４～１８の飽和もしくは不飽和のアルキル基もしくはアルコキシアルキル基である。
    Ｒ５は、キラルな基であり、上記式（３）で表される基である。
    Ｘ９～Ｘ２０は、それぞれ独立して－ＣＨ３、－ＣＦ３、ハロゲン原子または水素原子を表す。ただし、Ｘ９～Ｘ２０のうち１つ以上は、それぞれ独立して－ＣＨ３、－ＣＦ３またはハロゲン原子である。
    Ｋは、単結合またはシクロヘキサン環を表す。）     A first alignment substrate having a first substrate, a first electrode layer formed on the first substrate, and a first alignment film formed on the first electrode layer and rubbed;
    A second alignment substrate having a second substrate, a second electrode layer formed on the second substrate, and a second alignment film formed on the second electrode layer and rubbed;
    A liquid crystal display device comprising a liquid crystal layer formed between the first alignment film and the second alignment film and including a ferroelectric liquid crystal composition,
    The first alignment film and the second alignment film are arranged so that the rubbing treatment directions are parallel,
    The ferroelectric liquid crystal composition contains at least one chiral compound of a chiral compound A represented by the following general formula (1) and a chiral compound B represented by the following general formula (2). Liquid crystal display element.
    Figure JPOXMLDOC01-appb-C000001
     (In the above formula (1), R 1 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
    R 2 is a chiral group and is a group represented by the following general formula (3).
    Figure JPOXMLDOC01-appb-C000002
     (In the above formula (3), R 3 is a saturated or unsaturated alkyl or alkoxyalkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom.
    Y 1 represents —CH 3 or a fluorine atom. m is 0 or 1. n is 0 or 1. * Indicates a chiral center. )
    X 1 to X 8 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 1 to X 8 are each independently —CH 3 , —CF 3 or a halogen atom. )
    Figure JPOXMLDOC01-appb-C000003
     (In the above formula (2), R 4 is an achiral group and is a saturated or unsaturated alkyl group or alkoxyalkyl group having 4 to 18 carbon atoms which may be substituted with a halogen atom.
    R 5 is a chiral group, and is a group represented by the above formula (3).
    X 9 to X 20 each independently represent —CH 3 , —CF 3 , a halogen atom or a hydrogen atom. However, one or more of X 9 to X 20 are each independently —CH 3 , —CF 3 or a halogen atom.
    K represents a single bond or a cyclohexane ring. )
  2. 　前記第１配向膜の構成材料および前記第２配向膜の構成材料が互いに異なる組成を有することを特徴とする請求の範囲第１項に記載の液晶表示素子。 2. The liquid crystal display element according to claim 1, wherein the constituent material of the first alignment film and the constituent material of the second alignment film have different compositions.
PCT/JP2012/072804 2011-09-07 2012-09-06 Liquid crystal display element WO2013035810A1 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2011195502 2011-09-07
JP2011-195502 2011-09-07
JP2012137261 2012-06-18
JP2012-137261 2012-06-18

Publications (1)

Publication Number Publication Date
WO2013035810A1 true WO2013035810A1 (en) 2013-03-14

Family

ID=47832250

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2012/072804 WO2013035810A1 (en) 2011-09-07 2012-09-06 Liquid crystal display element

Country Status (2)

Country Link
JP (1) JP2014025044A (en)
WO (1) WO2013035810A1 (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6858495B2 (en) 2016-05-27 2021-04-14 エルジー ディスプレイ カンパニー リミテッド Liquid crystal display device and manufacturing method of liquid crystal display device
JP6824658B2 (en) * 2016-08-09 2021-02-03 エルジー ディスプレイ カンパニー リミテッド Liquid crystal display device and manufacturing method of liquid crystal display device
JP6859563B2 (en) * 2016-08-18 2021-04-14 エルジー ディスプレイ カンパニー リミテッド Liquid crystal display element and manufacturing method of liquid crystal display element
JP7092461B2 (en) * 2017-02-28 2022-06-28 エルジー ディスプレイ カンパニー リミテッド Manufacturing method of liquid crystal display device and liquid crystal table device
JP6924588B2 (en) * 2017-02-28 2021-08-25 エルジー ディスプレイ カンパニー リミテッド Manufacturing method of liquid crystal display device and liquid crystal table device
JP6985024B2 (en) * 2017-03-10 2021-12-22 エルジー ディスプレイ カンパニー リミテッド Liquid crystal display device

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008233713A (en) * 2007-03-23 2008-10-02 Sony Corp Liquid crystal display device and electronic equipment
WO2010031431A1 (en) * 2008-09-17 2010-03-25 Tetragon Lc Chemie Ag Chiral compounds, cholesteric and ferroelectric liquid crystal compositions comprising these chiral compounds, and liquid crystal displays comprising these liquid crystal compositions

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008233713A (en) * 2007-03-23 2008-10-02 Sony Corp Liquid crystal display device and electronic equipment
WO2010031431A1 (en) * 2008-09-17 2010-03-25 Tetragon Lc Chemie Ag Chiral compounds, cholesteric and ferroelectric liquid crystal compositions comprising these chiral compounds, and liquid crystal displays comprising these liquid crystal compositions

Also Published As

Publication number Publication date
JP2014025044A (en) 2014-02-06

Similar Documents

Publication Publication Date Title
KR101073781B1 (en) Liquid crystal display device
JP4753149B2 (en) Liquid crystal display element
WO2013035810A1 (en) Liquid crystal display element
JP4520314B2 (en) Liquid crystal display element
JP5062182B2 (en) Liquid crystal display element
JP2009181063A (en) Liquid crystal display element and method of manufacturing the same
JPH10338877A (en) Smectic liquid crystal material and optical liquid crystal element
JP4888049B2 (en) Liquid crystal display element
WO2013035811A1 (en) Ferroelectric liquid crystal composition and liquid crystal display element
JP2013241536A (en) Ferroelectric liquid crystal composition and liquid crystal display element
JP2007094020A (en) Liquid crystal display device
JP2013216848A (en) Ferroelectric liquid crystal composition and liquid crystal display element
WO2013035812A1 (en) Ferroelectric liquid crystal composition and liquid crystal display element
WO2013035809A1 (en) Ferroelectric liquid crystal composition and liquid crystal display element
JP2014234477A (en) Ferroelectric liquid crystal composition and liquid crystal display element
JP2001226674A (en) Monostable ferroelectric liquid crystal display device
JP2013107965A (en) Response time accelerator for ferroelectric liquid crystal, ferroelectric liquid crystal composition, and liquid crystal display element
JP2013147592A (en) Ferroelectric liquid crystal composition and liquid crystal display element
JP2013228524A (en) Liquid crystal display element
JP2013227383A (en) Ferroelectric liquid crystal composition and liquid crystal display element
JP2014019647A (en) Compound, ferroelectric liquid crystal composition using the same and liquid crystal display
JP2013144734A (en) Ferroelectric liquid crystal composition and liquid crystal display element
JP2014015558A (en) Ferroelectric liquid crystal composition and liquid crystal display device
JP2014015562A (en) Ferroelectric liquid crystal composition and liquid crystal display device
JP4951818B2 (en) Ferroelectric liquid crystal composition and liquid crystal display device using the same

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12830374

Country of ref document: EP

Kind code of ref document: A1

DPE2 Request for preliminary examination filed before expiration of 19th month from priority date (pct application filed from 20040101)
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12830374

Country of ref document: EP

Kind code of ref document: A1