CN116323765A - Resin for pigment-dispersion master batch for adhesive, colored adhesive composition, and adhesive sheet - Google Patents
Resin for pigment-dispersion master batch for adhesive, colored adhesive composition, and adhesive sheet Download PDFInfo
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- CN116323765A CN116323765A CN202180066952.1A CN202180066952A CN116323765A CN 116323765 A CN116323765 A CN 116323765A CN 202180066952 A CN202180066952 A CN 202180066952A CN 116323765 A CN116323765 A CN 116323765A
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- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/20—Compounding polymers with additives, e.g. colouring
- C08J3/22—Compounding polymers with additives, e.g. colouring using masterbatch techniques
- C08J3/226—Compounding polymers with additives, e.g. colouring using masterbatch techniques using a polymer as a carrier
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
- C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
- C08F220/10—Esters
- C08F220/12—Esters of monohydric alcohols or phenols
- C08F220/16—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms
- C08F220/18—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms with acrylic or methacrylic acids
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- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/20—Compounding polymers with additives, e.g. colouring
- C08J3/22—Compounding polymers with additives, e.g. colouring using masterbatch techniques
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
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- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L33/00—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides or nitriles thereof; Compositions of derivatives of such polymers
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- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J7/00—Adhesives in the form of films or foils
- C09J7/30—Adhesives in the form of films or foils characterised by the adhesive composition
- C09J7/38—Pressure-sensitive adhesives [PSA]
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J7/00—Adhesives in the form of films or foils
- C09J7/30—Adhesives in the form of films or foils characterised by the adhesive composition
- C09J7/38—Pressure-sensitive adhesives [PSA]
- C09J7/381—Pressure-sensitive adhesives [PSA] based on macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
- C09J7/385—Acrylic polymers
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Abstract
The present invention relates to a resin for pigment dispersion master batch for adhesives, which contains a resin (A) having a glass transition temperature of-80 to 40 ℃ and an acid value of 1 to 50 (KOHmg/g).
Description
Technical Field
The invention relates to a pigment dispersion masterbatch resin for adhesives, a pigment dispersion masterbatch for adhesives, a colored adhesive composition and an adhesive sheet.
Background
Since a member using an adhesive can be peeled off by a simple operation, an exterior member and a decorative adhesive member each of which is obtained by providing a colored adhesive layer on a base material are used in various fields.
Further, an adhesive layer has been studied which can realize various colors at a desired concentration and brightness, is less likely to be discolored even when used outdoors or exposed to ultraviolet light, and uses a pigment as a color material excellent in weather resistance.
Known are: pigments have poor dispersibility compared to dyes, but the use of dispersants can improve the dispersibility and color uniformity in adhesives. However, when the dispersant is a low molecular compound or a surfactant, there is a risk that the dispersant bleeds out and the adhesive stability of the adhesive is lowered. To reduce this risk, it was studied to cover the particle surface with a resin dispersant.
For example, patent document 1 describes a colored adhesive sheet having an adhesive layer formed of an adhesive composition containing an adhesive component and a pigment dispersion containing a pigment and a dispersion resin, wherein the mass ratio of the pigment to the dispersion resin is set to a specific range.
Patent document 2 describes a colored adhesive sheet having excellent weather resistance, which is obtained by sandwiching a thin layer of a colored adhesive between a transparent film having excellent weather resistance and a release paper, wherein the thin layer of the colored adhesive is obtained by uniformly and densely kneading and dispersing a binder based on polyacrylate and pigment particles covered with an acrylic resin having no reactive group.
Patent document 3 describes an optical adhesive comprising an adhesive resin (a) having a weight average molecular weight of 20 to 200 ten thousand, a pigment (B), a dispersant (C) and a curing agent (D) for the purpose of obtaining an optical adhesive which has a color tone correction function for adjusting the color tone of an optical member such as a display, can realize a thin film, maintains high adhesion and pigment dispersibility even when exposed to a high temperature/high humidity environment for a long period of time, and is excellent in transparency.
In the field of colored resins used for injection molding and the like, a masterbatch containing a pigment is used as a means for coloring the resin.
Prior art literature
Patent literature
Patent document 1: japanese patent laid-open publication 2016-98300
Patent document 2: japanese patent laid-open No. 57-021473
Patent document 3: japanese patent laid-open publication No. 2013-67782
Disclosure of Invention
Problems to be solved by the invention
In the prior art, the adhesive resin, the pigment and the dispersant are simply mixed, and the pigment dispersibility in the adhesive resin is insufficient, and the colored adhesive layer may have uneven color in appearance. In addition, there is a problem in the adhesion stability of the adhesive, such as a decrease in adhesive strength with time in a high-temperature and high-humidity environment.
In the field of colored resins used for injection molding and the like, a masterbatch containing a pigment is used, but since the adhesive that has not undergone a thermoforming step cannot be heated, melted and kneaded, no attempt has been made to apply the masterbatch to the adhesive.
Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and an object of the present invention is to provide a resin for a pigment-dispersion master batch for a binder, a colored binder composition, and a binder sheet, which can form a binder layer that combines both pigment dispersibility and adhesion reliability.
Solution for solving the problem
The present inventors have focused on the pigment dispersion process and have studied and as a result, succeeded in coating the surface of a pigment with a resin (a) having a specific glass transition temperature (Tg) and a specific acid value to obtain a resin for a pigment dispersion master batch for a binder, which is easily dispersed in a binder composition.
And found that: the present invention has been completed by adjusting the content ratio of a pigment-dispersion master batch resin for a binder containing a resin having a specific Tg and a specific acid value to a pigment, thereby obtaining a pigment-dispersion master batch for a binder excellent in dispersibility and a binder layer exhibiting excellent appearance and high adhesion reliability.
Namely, the present invention is as follows.
[ 1 ] A resin for pigment-dispersion master batch for adhesives, which contains a resin (A),
the glass transition temperature of the resin (A) is-80 to 40 ℃,
the acid value of the resin (A) is 1 to 50 (KOHmg/g).
[ 2 ] A pigment-dispersion master batch for adhesives comprising the resin for pigment-dispersion master batch for adhesives described in [ 1 ], and a pigment,
the content of the resin (A) is 45 to 90 mass% relative to the total mass of the pigment and the resin (A).
[ 3 ] A colored adhesive composition comprising the pigment-dispersion master batch for adhesive according to [ 2 ] and a base polymer.
The colored adhesive composition according to [ 4 ], wherein the base polymer is an acrylic polymer.
[ 5 ] an adhesive sheet comprising an adhesive layer formed of the colored adhesive composition described in [ 3 ] or [ 4 ].
ADVANTAGEOUS EFFECTS OF INVENTION
According to the present invention, an adhesive layer and an adhesive sheet exhibiting excellent appearance and high adhesion reliability, a colored adhesive composition capable of forming the adhesive layer and the adhesive sheet, a pigment dispersion master batch for an adhesive having excellent dispersibility, and a resin for the pigment dispersion master batch for an adhesive can be provided.
Drawings
Fig. 1 is an example of a schematic cross-sectional view of an adhesive sheet according to an embodiment of the present invention.
Fig. 2 is an example of a schematic cross-sectional view of an adhesive sheet according to an embodiment of the present invention.
Fig. 3 is an example of a schematic cross-sectional view of an adhesive sheet according to an embodiment of the present invention.
Detailed Description
The present invention will be described in detail below with reference to the drawings, but the present invention is not limited to the following embodiments and can be implemented by any modification within the scope of the gist of the present invention. The terms "to" representing the numerical range "are used in a meaning including the numerical values described before and after the term" lower limit value "and" upper limit value ".
In the present specification, "adhesive" means: a material which exhibits a soft solid (viscoelastic) state in a temperature range around room temperature and has a property of being easily adhered to an adherend by pressure. The adhesives mentioned here are, for example, "C.A. Dahlquist," Adhesion: fundamental and Practice ", mcLaren&Sons, (1966) P.143", may be a material having a tensile modulus of elasticity E satisfying the complex number * (1Hz)<107dyne/cm 2 Materials of this nature (typically materials having the above properties at 25 ℃).
In the present specification, unless otherwise specified, "main component" refers to a component whose content exceeds 50 mass%.
In this specification, the percentage or the like based on mass is the same as the percentage or the like based on weight.
[ resin for pigment Dispersion masterbatch for Binder ]
The pigment-dispersion masterbatch-used resin for a binder according to an embodiment of the present invention (hereinafter may be simply referred to as masterbatch-used resin) is a pigment-dispersion masterbatch-used resin for a binder containing the resin (a),
the Tg of the resin (A) is-80 to 40 ℃,
the acid value of the resin (A) is 1 to 50 (KOHmg/g).
Here, the master batch means: a resin composition containing a colorant at a high concentration, which is used for uniformly and easily dispersing a colorant such as a pigment or a dispersion other than the colorant as needed in a target dispersion medium. In addition, the pigment dispersion master batch is a resin composition for dispersing pigments.
The binder pigment dispersion masterbatch resin according to the embodiment of the present invention is a resin used in the binder pigment dispersion masterbatch.
As described above, conventionally, the binder composition, the pigment, and the dispersant are simply mixed to disperse the pigment in the binder layer, but the dispersion of the pigment is insufficient, and uneven appearance occurs. The present inventors have focused on the process of pigment dispersion and have studied and, as a result, have found that: by using the resin (a) having a specific Tg and a specific acid value, the pigment in the form of a masterbatch can be dispersed in the adhesive composition with good dispersibility. The pigment is coated with the resin (a) to form a fine masterbatch, and the fine masterbatch is then used to obtain a pigment-dispersion masterbatch resin for a binder which is easily dispersed in a binder composition.
The adhesive composition, which will be described later in detail, contains a base polymer. Conventional pigment-containing masterbatches are sometimes used for coloring resins for injection molding, which have undergone a heating step and a mechanical kneading step, and resins for injection molding, which have been dissolved during heat treatment, are often used as resins having a high Tg. In the embodiment of the present invention, from the viewpoints of ease of mixing with a resin (base polymer) used in the binder, dispersibility, compatibility, solubility in a solvent, and the like, a resin (a) having a Tg lower than that of a resin dispersant generally used is used, whereby a pigment dispersion master batch resin for a binder capable of being highly dispersed in a binder composition can be obtained.
Instead of simply mixing the binder composition, pigment and dispersant and covering the surface of the pigment with the dispersant, the surface of the pigment is previously covered with the pigment dispersion master batch resin for a binder according to the embodiment of the present invention to form a micro master batch before mixing the binder composition with the pigment, and then mixed with the binder composition, whereby it is possible to form a binder layer excellent in adhesion reliability while not only improving dispersibility and suppressing appearance unevenness of the binder layer.
< resin (A) >
The resin (a) is preferably contained as a main component in the resin for pigment dispersion master batch for binder according to the embodiment of the present invention.
The resin (A) needs to be designed so that the glass transition temperature (Tg) becomes-80 to 40 ℃.
From the viewpoint of reduced compatibility with the base polymer in the adhesive composition and reduced influence on the adhesive properties, the Tg of the resin (a) is required to be 40 ℃ or less, preferably 20 ℃ or less, and more preferably 0 ℃ or less. From the viewpoint of handling, the Tg of the resin (A) is required to be-80℃or higher, preferably-70℃or higher, and more preferably-60℃or higher.
When the Tg of the resin (a) is set to 40 ℃ or lower, the resin (a) melts when the resin (a) is mixed with a pigment by kneading or the like, and the resin (a) is easily adsorbed to the pigment at the moment when aggregation of the pigment is broken up. Thus, the fine particles of the pigment are covered with the resin (a), and a micro master batch having excellent dispersion stability can be realized.
Here, tg of the resin (a) means: tg is determined by Fox formula based on the composition of the monomer component used in the synthesis of the resin (A). The Fox equation is a relational expression between Tg of the copolymer and glass transition temperature Tgi of a homopolymer obtained by homopolymerizing each of the monomers constituting the copolymer, as shown below.
1/Tg＝Σ(Wi/Tgi)
In the above Fox formula, tg represents the glass transition temperature (unit: K) of the copolymer; wi represents the mass fraction (copolymerization ratio on a mass basis) of monomer i in the copolymer; tgi represents the glass transition temperature (unit: K) of the homopolymer of monomer i.
The glass transition temperature of the homopolymer used for calculation of Tg was the value described in the known data. For example, the following values are used as the glass transition temperatures of the monomers listed below as homopolymers of the monomers.
For the glass transition temperatures of homopolymers of monomers other than those exemplified above, the values described in "Polymer Handbook" (3 rd edition, john Wiley & Sons, inc., 1989) are used. The highest value is used for the monomer having a plurality of values described in this document. In the case where the Polymer Handbook is not described, a value obtained by the measurement method described in Japanese patent application laid-open No. 2007-51271 is used.
The Tg of the resin (a) can be adjusted by appropriately changing the monomer composition (i.e., the kind and amount ratio of the monomers used in the synthesis of the polymer).
If the Tg of the resin (A) is within the above range, the type thereof is not particularly limited, and those known in the masterbatch art can be used. For example, the rubber-like polymer may be 1 or 2 or more kinds of various rubber-like polymers such as acrylic polymer, rubber-like polymer, polyester-like polymer, urethane-like polymer, polyether-like polymer, silicone-like polymer, polyamide-like polymer and fluorine-like polymer. From the viewpoints of dispersibility in adhesives, cost, and the like, an acrylic polymer or a rubber polymer is preferable, and an acrylic polymer is more preferable.
Hereinafter, description will be made mainly on the case where the resin (a) is an acrylic polymer, but it is not meant to limit that the resin (a) in the present embodiment is composed of an acrylic polymer.
"acrylic polymer" means: a polymer comprising, as monomer units constituting the polymer, monomer units derived from a monomer having at least one (meth) acryloyl group in 1 molecule. Hereinafter, a monomer having at least one (meth) acryloyl group in 1 molecule is also referred to as an "acrylic monomer". Thus, an acrylic polymer in this specification is defined as a polymer comprising monomer units derived from an acrylic monomer. Typical examples of the acrylic polymer include: the proportion of the acrylic monomer is more than 50 mass% of the acrylic polymer among all the monomer components used for synthesizing the acrylic polymer.
In addition, "(meth) acryl" is meant to refer to the meaning of acryl and methacryl in an inclusive sense. Likewise, "(meth) acrylate" is meant to refer to acrylate and methacrylate in an inclusive sense, and "(meth) acrylic" is meant to refer to acrylic and methacrylic in an inclusive sense.
The acrylic polymer is preferably a polymer containing, for example, an alkyl (meth) acrylate as a main monomer, and may further contain a monomer raw material of a sub-monomer having copolymerizability with the main monomer. The main monomer herein means a component that occupies more than 50 mass% of the monomer composition in the above monomer raw materials.
As the alkyl (meth) acrylate, for example, a compound represented by the following formula (1) can be suitably used.
CH 2 ＝C(R 1 )COOR 2 (1)
Here, R in the above formula (1) 1 Is a hydrogen atom or a methyl group. In addition, R 2 Is a chain alkyl group having 1 to 20 carbon atoms. Hereinafter, the range of the number of carbon atoms is sometimes referred to as "C 1-20 ". R is preferably used from the viewpoint of adhesion stability of the adhesive 2 Is C 1-14 (e.g. C 2-10 Typically C 4-8 ) Alkyl (meth) acrylates of chain alkyl groups as main monomers. From the viewpoint of adhesion properties, R is preferably 1 Is a hydrogen atom and R 2 Is C 4-8 Alkyl acrylate of chain alkyl (hereinafter also referred to simply as acrylic acid C) 4-8 Alkyl esters) as main monomers.
As R 2 Is C 1-20 (meth) acrylic acid (C) of chain alkyl groupExamples of the alkyl acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, pentyl (meth) acrylate, isopentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, and eicosyl (meth) acrylate. These alkyl (meth) acrylates may be used alone or in combination of 1 or more than 2. Preferred alkyl (meth) acrylates include n-Butyl Acrylate (BA) and 2-ethylhexyl acrylate (2 EHA).
Typically, the proportion of the alkyl (meth) acrylate in the monomer component constituting the acrylic polymer exceeds 50% by mass, and may be 70% by mass or more, 85% by mass or more, or 90% by mass or more, for example. In addition, the proportion of the alkyl (meth) acrylate in the monomer component is typically less than 100 mass%, and is usually preferably 99.5 mass% or less, and may be 98 mass% or less (for example, less than 97 mass%) from the viewpoint of cohesive force or the like.
In the present embodiment, the monomer component may contain 50 mass% or more of (meth) acrylic acid C 4-8 The alkyl ester is preferably carried out. (meth) acrylic acid C 4-8 The proportion of the alkyl ester in the monomer component may be 70 mass% or more, or 85 mass% or more (for example, 90 mass% or more). On the other hand, from the viewpoint of cohesive force and the like, (meth) acrylic acid C 4-8 The proportion of alkyl esters in the monomer component is generally suitable99.5 mass% or less, 98 mass% or less (for example, less than 97 mass%) may be used.
In this embodiment, the monomer component constituting the resin (a) (for example, an acrylic polymer) may contain a carboxyl group-containing monomer. By making the monomer component contain a carboxyl group-containing monomer, the dispersion state of the pigment is easily optimized. In addition, the improvement of dispersion stability is also advantageous. Examples of the carboxyl group-containing monomer include ethylenically unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, crotonic acid, and isocrotonic acid; ethylenically unsaturated dicarboxylic acids such as maleic acid, itaconic acid and citraconic acid, and anhydrides thereof (maleic anhydride, itaconic anhydride and the like), and the like. They may be used either 1 alone or 2 in combination. Among them, preferable examples of the carboxyl group-containing monomer include Acrylic Acid (AA) and methacrylic acid (MAA). AA is particularly preferred.
In the embodiment in which the carboxyl group-containing monomer is copolymerized in the resin (a), the content of the carboxyl group-containing monomer in the monomer component constituting the resin (a) is not particularly limited, and may be, for example, 0.2 mass% or more (typically 0.5 mass% or more) of the monomer component, and is usually preferably 1 mass% or more, may be 2 mass% or more, and may be 3 mass% or more. By setting the content of the carboxyl group-containing monomer to more than 3 mass%, a higher effect is exhibited, and an adhesive layer having more excellent holding performance can be obtained. From this viewpoint, in one preferred embodiment, the content of the carboxyl group-containing monomer may be 3.2% by mass or more, more preferably 3.5% by mass or more, still more preferably 4% by mass or more, and may be 4.5% by mass or more of the monomer component. By copolymerizing the carboxyl group-containing monomer in the above amount, even when a pigment dispersion master batch for a binder, which will be described later, is blended into the binder layer, the pigment can be well dispersed in the layer, and it is preferable to realize adhesion characteristics such as adhesion stability.
The upper limit of the content of the carboxyl group-containing monomer is not particularly limited, and may be, for example, 15 mass% or less, 12 mass% or less, or 10 mass% or less. By limiting the copolymerization ratio of the carboxyl group-containing monomer to a predetermined amount or less, even when a pigment-dispersing master batch for a binder, which will be described later, is blended into the binder layer, the pigment can be dispersed well within the layer, and the adhesive properties such as adhesion can be maintained well. In this embodiment, the content of the carboxyl group-containing monomer may be preferably 7 mass% or less (typically, less than 7 mass%, for example, 6.8 mass% or less or 6.0 mass%) of the monomer component.
The secondary monomer having copolymerizability with the alkyl (meth) acrylate as the main monomer can contribute to introducing crosslinking points into the acrylic polymer or to improving the cohesive force of the acrylic polymer. As the auxiliary monomer, for example, 1 kind or 2 or more kinds of functional group-containing monomers (excluding the above carboxyl group-containing monomers) as described below may be used alone or in combination.
Hydroxyl-containing monomers: hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate; unsaturated alcohols such as vinyl alcohol and allyl alcohol; polypropylene glycol mono (meth) acrylate.
Amide group-containing monomers: such as (meth) acrylamide, N-dimethyl (meth) acrylamide, N-butyl (meth) acrylamide, N-methylol propane (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide.
Amino group-containing monomers: such as aminoethyl (meth) acrylate, N-dimethylaminoethyl (meth) acrylate, t-butylaminoethyl (meth) acrylate.
Monomers having epoxy groups: such as glycidyl (meth) acrylate, methyl glycidyl (meth) acrylate, allyl glycidyl ether.
Cyano-containing monomers: such as acrylonitrile, methacrylonitrile.
Ketone group-containing monomers: such as diacetone (meth) acrylamide, diacetone (meth) acrylate, vinyl methyl ketone, vinyl ethyl ketone, allyl acetoacetate, and vinyl acetoacetate.
Monomers having a ring containing a nitrogen atom: such as N-vinyl-2-pyrrolidone, N-methyl vinyl pyrrolidone, N-vinyl pyridine, N-vinyl piperidone, N-vinyl pyrimidine, N-vinyl piperazine, N-vinyl pyrazine, N-vinyl pyrrole, N-vinyl imidazole, N-vinyl oxazole, N-vinyl morpholine, N-vinyl caprolactam, N- (meth) acryloyl morpholine.
Alkoxysilyl group-containing monomer: such as 3- (meth) acryloxypropyl trimethoxysilane, 3- (meth) acryloxypropyl triethoxysilane, 3- (meth) acryloxypropyl methyldimethoxysilane, 3- (meth) acryloxypropyl methyldiethoxysilane.
In the case where the monomer component constituting the acrylic polymer contains the functional group-containing monomer as described above, the content of the functional group-containing monomer in the monomer component is not particularly limited. The content of the functional group-containing monomer in the monomer component may be, for example, 0.1 mass% or more, and is usually preferably 0.5 mass% or more, and may be 1 mass% or more, from the viewpoint of appropriately exhibiting the effect caused by the use of the functional group-containing monomer. In terms of the relationship with the main monomer and the carboxyl group-containing monomer, the content of the functional group-containing monomer in the monomer component is preferably 40 mass% or less, preferably 20 mass% or less, and may be 10 mass% or less (for example, 5 mass% or less) from the viewpoint of compatibility with the base polymer used in the adhesive composition and easiness of achieving a balance of dispersibility. The techniques disclosed herein may be preferably practiced in a manner such that the monomer component is substantially free of functional group-containing monomers (e.g., such that the monomer component consists essentially of only alkyl (meth) acrylate and carboxyl group-containing monomers). The monomer component substantially free of the functional group-containing monomer means that at least the functional group-containing monomer is not intentionally used, and it is acceptable that the functional group-containing monomer is not intentionally contained in an amount of, for example, 0.05 mass% or less (typically 0.01 mass% or less). The acrylic polymer having such a monomer composition can easily disperse a pigment-dispersion master batch for a binder, which will be described later.
The monomer component constituting the acrylic polymer may contain other copolymerized components in addition to the above-mentioned auxiliary monomers for the purpose of improving cohesive force and the like. Examples of the other copolymerizable component include vinyl ester monomers such as vinyl acetate, vinyl propionate and vinyl laurate; aromatic vinyl compounds such as styrene, substituted styrene (α -methylstyrene, etc.), and vinyl toluene; cycloalkyl (meth) acrylates such as cyclohexyl (meth) acrylate, cyclopentyl (meth) acrylate, isobornyl (meth) acrylate, and the like; aromatic ring-containing (meth) acrylates such as aryl (meth) acrylates (e.g., phenyl (meth) acrylate), aryloxyalkyl (meth) acrylates (e.g., phenoxyethyl (meth) acrylate), and arylalkyl (meth) acrylates (e.g., benzyl (meth) acrylate); olefin monomers such as ethylene, propylene, isoprene, butadiene, and isobutylene; chlorine-containing monomers such as vinyl chloride and vinylidene chloride; isocyanate group-containing monomers such as 2- (meth) acryloyloxyethyl isocyanate; an alkoxy group-containing monomer such as methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate; vinyl ether monomers such as methyl vinyl ether and ethyl vinyl ether; and a polyfunctional monomer having 2 or more (for example, 3 or more) polymerizable functional groups (for example, (meth) acryl) in 1 molecule such as 1, 6-hexanediol di (meth) acrylate and trimethylolpropane tri (meth) acrylate.
The amount of the other copolymerizable component is not particularly limited as long as it is appropriately selected according to the purpose and use, and is usually preferably 0.05 mass% or more and may be 0.5 mass% or more from the viewpoint of appropriately exhibiting the effect caused by use. The content of the other copolymerizable component in the monomer component is usually preferably 20 mass% or less, and may be 10 mass% or less (for example, 5 mass% or less) from the viewpoint of easily balancing the adhesive properties. In the present embodiment, the monomer component may be preferably carried out so as to be substantially free of other copolymerizable components. The monomer component substantially not containing the other copolymerizable component means that at least the other copolymerizable component is not intentionally used, and it is acceptable that the other copolymerizable component is not intentionally contained, for example, in an amount of 0.01 mass% or less. The acrylic polymer having such a monomer composition can easily disperse a pigment-dispersion master batch for a binder, which will be described later.
The method for obtaining the acrylic polymer is not particularly limited, and various polymerization methods known as a method for synthesizing an acrylic polymer, such as a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, a suspension polymerization method, and a photopolymerization method, can be suitably employed. For example, a solution polymerization method can be preferably employed. The polymerization temperature in the solution polymerization may be appropriately selected depending on the types of monomers and solvents used, the type of polymerization initiator, and the like, and may be, for example, 20℃to 170℃and, typically, 40℃to 140 ℃.
The solvent (polymerization solvent) used in the solution polymerization may be appropriately selected from conventionally known organic solvents. For example, aromatic compounds (typically, aromatic hydrocarbons) such as toluene can be used; acetate esters such as ethyl acetate; aliphatic hydrocarbons such as hexane and cyclohexane, and alicyclic hydrocarbons; halogenated alkanes such as 1, 2-dichloroethane; lower alcohols such as isopropyl alcohol (for example, monohydric alcohols having 1 to 4 carbon atoms); ethers such as t-butyl methyl ether; any one selected from 1 solvent or a mixed solvent of 2 or more kinds of ketones such as methyl ethyl ketone.
The initiator used in the polymerization may be appropriately selected from conventionally known polymerization initiators depending on the kind of the polymerization method. For example, 1 or 2 or more azo polymerization initiators such as 2,2' -Azobisisobutyronitrile (AIBN) can be preferably used. As other examples of the polymerization initiator, persulfate such as potassium persulfate can be given; peroxide initiators such as benzoyl peroxide and hydrogen peroxide; substituted ethane initiators such as phenyl-substituted ethane; aromatic carbonyl compounds, and the like. As another example of the polymerization initiator, a redox initiator based on a combination of a peroxide and a reducing agent can be cited. The polymerization initiator may be used alone or in combination of 1 or more than 2. The amount of the polymerization initiator to be used may be a usual amount, and may be selected from the range of 0.005 to 1 part by mass (typically 0.01 to 1 part by mass) based on 100 parts by mass of the monomer component.
According to the polymerization described above, a polymerization reaction liquid in which the resin (a) is dissolved in an organic solvent can be obtained. The pressure-sensitive adhesive layer in this embodiment may contain the above-mentioned polymerization reaction liquid or a resin (a) solution obtained by subjecting the reaction liquid to an appropriate post-treatment. As the resin (a), a resin obtained by desolvation of the polymerization reaction liquid described above can be used. Alternatively, the resin (a) synthesized by a polymerization method other than solution polymerization (for example, emulsion polymerization, photopolymerization, bulk polymerization, or the like) may be used as it is.
The weight average molecular weight (Mw) of the resin (A) (suitably an acrylic polymer) in the technology disclosed herein is not particularly limited, and may be, for example, 10X 10 4 ～500×10 4 Is not limited in terms of the range of (a). From the viewpoint of dispersibility, mw of the resin (A) is preferably 30X 10 4 ～200×10 4 (more preferably 45X 10) 4 ～150×10 4 Typically 65X 10 4 ～130×10 4 ) Is not limited in terms of the range of (a). Here, mw refers to a value in terms of standard polystyrene obtained by GPC (gel permeation chromatography). As a GPC apparatus, for example, model name "HLC-8320GPC" (column: TSKgelGMH-H (S), manufactured by Tosoh Co., ltd.) may be used.
The acid value of the resin (A) in the embodiment of the present invention is required to be designed so as to be 1 to 50 KOHmg/g. From the viewpoint of improving the dispersion stability of the pigment, it is preferably 5KOHmg/g or more, more preferably 10KOHmg/g or more. In addition, from the viewpoint of preventing corrosion of an adherend when an adhesive layer containing the pigment-dispersion masterbatch-used resin for adhesive according to the embodiment of the invention is adhered to the adherend, it is preferably 50KOHmg/g or less, more preferably 30KOHmg/g or less, and still more preferably 20KOHmg/g or less.
In the present embodiment, the acid value of the resin (A) may be measured by a potential difference titration method defined in JIS K0070:1992.
For example, in the above acrylic polymer, the acid value is the mg of potassium hydroxide required for neutralizing 1g of carboxylic acid in the acrylic polymer.
[ pigment Dispersion masterbatch for Binder ]
The pigment-dispersion master batch for a binder according to the embodiment of the present invention is used for a binder, and is prepared into a master batch for dispersing a pigment in the binder.
By using the pigment dispersion master batch for a binder according to the embodiment of the present invention for coloring a binder, excellent pigment dispersibility can be obtained, and a binder layer having high adhesion reliability can be obtained.
The pigment-dispersion master batch for a binder according to an embodiment of the present invention includes a resin for a pigment-dispersion master batch for a binder and a pigment,
the content of the resin (A) is 45 to 90 mass% relative to the total mass of the pigment and the resin (A).
From the viewpoint of easily imparting shear when kneading and breaking the pigment with the resin (a), the content of the resin (a) is preferably 45 mass% or more, more preferably 50 mass% or more, and still more preferably 60 mass% or more, with respect to the total mass of the pigment and the resin (a). In addition, from the viewpoint of viscosity adjustment at the time of kneading the pigment and the resin (a) and breaking the pigment, it is preferably 90 mass% or less, more preferably 85 mass% or less, and still more preferably 80 mass% or less.
In the pigment-dispersion master batch for a binder according to the embodiment of the present invention, the surface of the pigment is covered with the resin (a) in the process of dispersing the pigment into the resin (a), and the shape thereof is not particularly limited, and may be solid such as powder or granule at normal temperature (25 ℃) or may be slurry. The conventional masterbatch is solid at normal temperature, but the pigment dispersion masterbatch for a binder according to the embodiment of the present invention may be in a paste form at normal temperature because Tg of the resin (a) is lower than that of the resin used in the conventional masterbatch. In the case of a slurry, dispersibility in the adhesive composition is improved, and thus it is preferable.
(pigment)
The pigment type used in the present embodiment is not particularly limited, and both organic pigments and inorganic pigments can be used.
Examples of the organic pigment include azo pigments such as azo lake pigments, insoluble monoazo pigments, insoluble disazo pigments, condensed azo pigments, chelate azo pigments, and the like; polycyclic pigments such as phthalocyanine pigments, perylene pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, thioindigo pigments, isoindolone pigments, quinophthalone pigments, and the like; chelate compounds such as basic dye type chelate compounds and acid dye type chelate compounds; a nitro pigment; nitroso pigments, and the like. They may be used singly or in combination of 2 or more.
Examples of the inorganic pigment include titanium oxide, iron oxide, indian red, chromium oxide, prussian blue, ultramarine, molybdenum red, iron black, and chrome yellow. They may be used singly or in combination of 2 or more.
Among them, if light resistance is considered, isoindolone pigments, quinacridone pigments, condensed azo pigments, phthalocyanine pigments, quinophthalone pigments, anthraquinone pigments are suitably used.
As a specific example of the organic pigment, examples thereof include pigment yellow 1 (chroma index (hereinafter referred to as c.i.) 11680), pigment yellow 3 (c.i. 11710), pigment yellow 14 (c.i. 21095), pigment yellow 17 (c.i. 21105), pigment yellow 42 (c.i. 77492), pigment yellow 74 (c.i. 11741), pigment yellow 83 (c.i. 21108), pigment yellow 93 (c.i. 20710), pigment yellow 98 (c.i. 11727), pigment yellow 109 (c.i. 56284), pigment yellow 110 (c.i. 56280), pigment yellow 128 (c.i. 20037), pigment yellow 129 (c.i. 48042), pigment yellow 138 (c.i. 56300), pigment yellow 139 (c.i. 298), pigment yellow 147 (c.i. 60645), pigment yellow pigment yellow 150 (c.i.12764), pigment yellow 154 (c.i.11781), pigment yellow 155 (c.i.200310), pigment yellow 180 (c.i.21290), pigment yellow 185 (c.i.56280), pigment yellow 199 (c.i.653200), pigment orange 5 (c.i.12075), pigment orange 13 (c.i.21110), pigment orange 16 (c.i.21160), pigment orange 34 (c.i.21160), pigment orange 43 (c.i.71105), pigment orange 61 (c.i.11265), pigment orange 71 (c.i.561200), pigment red 5 (c.i.12490), pigment red 8 (c.i.12335), pigment red 17 (c.i.12390), pigment red 22 (c.i.12315), pigment red 48:2 (c.i.15865:2), pigment red 112 (c.i.12370), pigment red 122 (c.i.73915), pigment red 170 (c.i.12475), pigment red 176 (c.i.12515), pigment red 177 (c.i.65300), pigment red 178 (c.i.71155), pigment red 179 (c.i.71130), pigment red 185 (c.i.12516), pigment red 202 (c.i.73907), pigment red 208 (c.i.12514), pigment red 254 (c.i.56110), pigment red 255 (c.i.561050), pigment red 264, pigment red 272 (c.i.561150), pigment violet 19 (c.i.73900), pigment violet 23 (c.i.51319), pigment blue 15:1 (c.i. 74160), pigment blue 15:3 (c.i. 74160), pigment blue 15:4 (c.i. 74160), pigment blue 60 (c.i. 69800), pigment green 7 (c.i. 74260), pigment green 36 (c.i. 74265), and the like, and preferably a mixture of 1 or 2 or more.
Specific examples of the inorganic pigment include pigment yellow 42 (c.i. 77492), pigment white 6 (c.i. 77891), pigment blue 27 (c.i. 77510), pigment blue 29 (c.i. 77007), and pigment black 7 (c.i. 77266), and a mixture of 1 or 2 or more types is preferable.
In particular, pigment yellow 74 (c.i. 11741), pigment yellow 109 (c.i. 56284), pigment yellow 110 (c.i. 56280), pigment yellow 128 (c.i. 20037), pigment yellow 138 (c.i. 51319), pigment yellow 150 (c.i. 12764), pigment yellow 155 (c.i. 200310), pigment yellow 180 (c.i. 21290), pigment green 7 (c.i. 74160), pigment green 36 (c.i. 74265), pigment red 122 (c.i. 73915), pigment red 177 (c.i. 65300), pigment red 202 (c.i. 73907), pigment red 254 (c.i. 56110), pigment violet 19 (c.i. 73900), pigment violet 23 (c.i. 51319), pigment blue 15:1 (c.i. 74160), pigment blue 15:3 (c.i. 74160), pigment blue 15:4 (c.i. 74160), pigment blue 15:696 (c.i. 74160), pigment black (c.i. 7460), and the like are preferable in view of hue, tinting and the like.
As the green pigment, 1 or more pigments selected from the group consisting of pigment green 7 (c.i. 74260), pigment green 36 (c.i. 74265), pigment yellow 138 (c.i. 56300), and pigment yellow 150 (c.i. 12764) can be suitably used.
As blue pigments, pigments of pigment blue 15:6 (C.I.74160) and/or pigment violet 23 (C.I.51319) may be suitably used.
The pigment may be in the form of a powder, a granule or a wet cake, a slurry.
In the present embodiment, the average particle diameter of the pigment is not particularly limited. The lower limit of the average particle diameter of the pigment may be, for example, 10nm or more, 50nm or more, 100nm or more, or 150nm or more from the viewpoint of ease of handling. The upper limit of the average particle diameter of the pigment is, for example, 500nm or less, 300nm or less, 250nm or less, or 200nm or less from the viewpoint of optical characteristics such as haze of the colored binder.
The average particle diameter of the pigment is a volume average particle diameter, specifically, a particle diameter (50% volume average particle diameter; hereinafter, also abbreviated as "D" in some cases) at 50% of the cumulative value in the particle size distribution measured by a particle size distribution measuring apparatus based on a laser scattering diffraction method 50 ). As the measuring device, for example, the product name "MICROTRAC MT3000II" manufactured by MICROTRAC-BEL company or an equivalent thereof can be used.
The pigment-dispersion master batch for a binder according to the embodiment of the present invention may contain various additives such as a plasticizer, a lubricant, an antioxidant, and an antistatic agent, if necessary.
The method for producing the pigment-dispersion master batch for a binder according to the embodiment of the present invention is not particularly limited, and examples thereof include: the resin (a) and the pigment are kneaded using a three-roll mill, a banbury mixer, a twin-screw extruder, a kneader, or the like, and the pigment is dispersed in the resin (a) and covered by the resin (a) to be kneaded and dispersed. The temperature at the time of dispersion is usually 100 to 180℃and the dispersion time is usually 1 minute to 1 hour.
The pigment-dispersion master batch for a binder according to the embodiment of the present invention is used for a binder, and a colored binder composition can be obtained by dispersing the pigment-dispersion master batch for a binder in the binder composition.
Hereinafter, a colored adhesive composition containing the pigment-dispersion master batch for adhesive according to the embodiment of the present invention will be described.
[ colored adhesive composition ]
The colored adhesive composition according to an embodiment of the present invention includes a pigment-dispersion masterbatch for an adhesive and a base polymer.
The colored adhesive composition is a colored adhesive composition, and may be a composition obtained by adding a pigment dispersion master batch for an adhesive to an adhesive composition containing a base polymer.
In the present embodiment, the form of adding the pigment-dispersion master batch for a binder to the binder composition is not particularly limited. For example, the pigment-dispersion master batch for a binder may be added directly to the binder composition, or may be added to the binder composition in the form of a dispersion in which the pigment-dispersion master batch for a binder is dispersed in a dispersion medium.
When the pigment dispersion master batch for a binder is dispersed in a wet manner using a dispersion medium, the pigment dispersion master batch is in a state of being solvated with the dispersion medium, and the dispersibility when added to the binder composition is improved.
In the case of preparing a dispersion in which a pigment dispersion master batch for a binder is dispersed in a dispersion medium, the median particle diameter of pigment particles in the dispersion is preferably 10nm or more, more preferably 30nm or more, and still more preferably 50nm or more from the viewpoint of the viscosity of the dispersion or the like. Further, from the viewpoint of avoiding productivity such as clogging of a filter in the colored adhesive manufacturing process, it is preferably 10 μm or less, more preferably 3 μm or less, and still more preferably 1 μm or less.
For example, as a method for measuring the median particle diameter, a laser diffraction/scattering type particle diameter distribution measuring apparatus LA-950 (manufactured by horiba ltd.) may be used, and the measurement may be performed using ethyl acetate as a dispersion medium. The relative refractive index is calculated from the refractive index of each of ethyl acetate and the pigment used, and the relative refractive index is measured, whereby the dispersed particles of the pigment in the dispersion liquid can be measured. From the measurement result, the median particle diameter of the dispersed particles of the pigment in the dispersion can be obtained.
The dispersion medium constituting the dispersion liquid is not particularly limited, and examples thereof include water (ion-exchanged water, reverse osmosis water, distilled water, etc.), various organic solvents (alcohols such as ethanol, ketones such as acetone, ethers such as butyl cellosolve and propylene glycol monomethyl ether acetate, esters such as ethyl acetate, aromatic hydrocarbons such as toluene, mixed solvents thereof, and aqueous mixed solvents of water and the above organic solvents. The dispersion may contain a dispersant described later. The above-mentioned dispersion liquid is mixed with the binder composition to thereby provide the colored binder composition containing the pigment dispersion master batch for binder and the base polymer, and further, additives such as a dispersant described later may be contained as optional components.
The compounding amount of the pigment-dispersion master batch for binder in the colored binder composition is not particularly limited. In general, the amount is preferably 0.5 parts by mass or more based on 100 parts by mass of the base polymer, and from the viewpoint of light shielding properties, it is preferably 1.0 parts by mass or more, more preferably 2.0 parts by mass or more, and still more preferably 3.0 parts by mass or more (for example, 4.0 parts by mass or more).
In addition, from the viewpoint of suppressing the deterioration of the adhesive properties that may occur due to the compounding of the pigment-dispersion masterbatch for a binder, the upper limit of the compounding amount of the pigment-dispersion masterbatch for a binder is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, still more preferably 8 parts by mass or less, and still more preferably 6 parts by mass or less, relative to 100 parts by mass of the base polymer.
(base Polymer)
The "base polymer" in the present embodiment means a main component of the rubbery polymer contained in the adhesive. The rubbery polymer means a polymer exhibiting rubber elasticity in a temperature region around room temperature.
In the present embodiment, the type of the base polymer is not particularly limited, and any known base polymer in the field of adhesives can be used. For example, 1 or 2 or more kinds of rubbery polymers such as acrylic polymers, rubber polymers, polyester polymers, urethane polymers, polyether polymers, silicone polymers, polyamide polymers and fluorine polymers may be contained as the base polymer. From the viewpoints of adhesive performance, cost, and the like, it is preferable to contain an acrylic polymer or a rubber polymer as a base polymer. Among them, the base polymer is more preferably an acrylic polymer from the viewpoint of dispersibility of the pigment dispersion master batch for a binder. Hereinafter, an adhesive composition containing an acrylic polymer as a base polymer will be mainly described, but the adhesive composition in the present embodiment is not limited to be composed of an acrylic polymer.
The acrylic polymer is preferably a polymer containing, for example, an alkyl (meth) acrylate as a main monomer, and may further contain a monomer raw material of a sub-monomer having copolymerizability with the main monomer. The main monomer herein means a component that occupies more than 50 mass% of the monomer composition in the above monomer raw materials.
As the alkyl (meth) acrylate, for example, a compound represented by the following formula (1) can be suitably used.
CH 2 ＝C(R 1 )COOR 2 (1)
Here, R in the above formula (1) 1 Is a hydrogen atom or a methyl group. In addition, R 2 Is a chain alkyl group having 1 to 20 carbon atoms. Hereinafter, the range of the number of carbon atoms is sometimes referred to as "C 1-20 ". R is preferably used from the viewpoint of adhesion stability of the adhesive 2 Is C 1-14 (e.g. C 2-10 Typically C 4-8 ) Alkyl (meth) acrylates of chain alkyl groups as main monomers. From the viewpoint of adhesion properties, R is preferably 1 Is a hydrogen atom and R 2 Is C 4-8 Alkyl acrylate of chain alkyl (hereinafter also referred to simply as acrylic acid C) 4-8 Alkyl esters) as main monomers.
As R 2 Is C 1-20 Examples of the alkyl (meth) acrylate of the chain alkyl group of (a) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, pentyl (meth) acrylate, isopentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, octyl (meth) acrylate, and isodecyl (meth) acrylate ) Heptadecyl acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, eicosyl (meth) acrylate, and the like. These alkyl (meth) acrylates may be used alone or in combination of 1 or more than 2. Preferred alkyl (meth) acrylates include n-Butyl Acrylate (BA) and 2-ethylhexyl acrylate (2 EHA).
Typically, the proportion of the alkyl (meth) acrylate in the monomer component constituting the acrylic polymer exceeds 50% by mass, and may be 70% by mass or more, 85% by mass or more, or 90% by mass or more, for example. In addition, the proportion of the alkyl (meth) acrylate in the monomer component is typically less than 100 mass%, and is usually preferably 99.5 mass% or less, and may be 98 mass% or less (for example, less than 97 mass%) from the viewpoint of cohesive force or the like.
In the present embodiment, the monomer component may contain 50 mass% or more of (meth) acrylic acid C 1-4 The alkyl ester is preferably carried out. (meth) acrylic acid C 1-4 The proportion of the alkyl ester in the monomer component may be 70 mass% or more, or 85 mass% or more (for example, 90 mass% or more). On the other hand, from the viewpoint of cohesive force and the like, (meth) acrylic acid C 1-4 The proportion of the alkyl ester in the monomer component is usually preferably 99.5 mass% or less, and may be 98 mass% or less (for example, less than 97 mass%).
In the present embodiment, the monomer component may contain 50 mass% or more (for example, 70 mass% or more, 85 mass% or more, or 90 mass% or more) of acrylic acid C 2-4 The alkyl ester is preferably carried out. As acrylic acid C 2-4 Specific examples of the alkyl esters include ethyl acrylate, propyl acrylate, isopropyl acrylate, n-Butyl Acrylate (BA), isobutyl acrylate, sec-butyl acrylate and tert-butyl acrylate. Acrylic acid C 2-4 The alkyl esters may be used alone or in combination of 1 or more than 2. According to this aspect, an adhesive sheet having excellent adhesion to an adherend can be easily realized. On the other hand, from the viewpoint of obtaining good cohesive force and the likeFrom the viewpoint of (meth) acrylic acid C 1-4 The proportion of the alkyl ester in the monomer component is usually preferably 99.5 mass% or less, and may be 98 mass% or less (for example, less than 97 mass%).
In another embodiment, the monomer component may contain 50 mass% or more (for example, 70 mass% or more, 85 mass% or more, or 90 mass% or more) of (meth) acrylic acid C 5-20 Alkyl esters. As (meth) acrylic acid C 5-20 Alkyl esters, preferably C (meth) acrylic acid 6-14 Alkyl esters. In one embodiment, acrylic acid C may be preferably used 6-10 Alkyl esters (e.g. acrylic acid C 8-10 Alkyl esters). (meth) acrylic acid C from the viewpoint of obtaining good cohesion and the like 5-20 The proportion of the alkyl ester in the monomer component is usually preferably 99.5 mass% or less, and may be 98 mass% or less (for example, less than 97 mass%).
In this embodiment, the monomer component constituting the base polymer (for example, acrylic polymer) may contain a carboxyl group-containing monomer. By including the carboxyl group-containing monomer in the monomer component, an adhesive layer exhibiting excellent adhesion reliability can be easily obtained. Examples of the carboxyl group-containing monomer include ethylenically unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, crotonic acid, and isocrotonic acid; ethylenically unsaturated dicarboxylic acids such as maleic acid, itaconic acid and citraconic acid, and anhydrides thereof (maleic anhydride, itaconic anhydride and the like), and the like. They may be used either 1 alone or 2 in combination. Among them, preferable examples of the carboxyl group-containing monomer include Acrylic Acid (AA) and methacrylic acid (MAA). AA is particularly preferred.
In the embodiment in which the carboxyl group-containing monomer is copolymerized in the base polymer, the content of the carboxyl group-containing monomer in the monomer component constituting the base polymer is not particularly limited, and may be, for example, 0.2 mass% or more (typically, 0.5 mass% or more) of the monomer component, and is usually preferably 1 mass% or more, may be 2 mass% or more, and may be 3 mass% or more. By setting the content of the carboxyl group-containing monomer to more than 3 mass%, a higher effect is exhibited, and an adhesive layer having more excellent adhesion reliability can be obtained. From this viewpoint, in one preferred embodiment, the content of the carboxyl group-containing monomer may be 3.2% by mass or more, more preferably 3.5% by mass or more, still more preferably 4% by mass or more, and may be 4.5% by mass or more of the monomer component. By copolymerizing the carboxyl group-containing monomer in the above amount, even when the pigment-dispersing master batch for a binder is blended into the binder layer, the pigment can be well dispersed in the layer, and it is preferable to achieve adhesion characteristics such as adhesion reliability.
The upper limit of the content of the carboxyl group-containing monomer is not particularly limited, and may be, for example, 15 mass% or less, 12 mass% or less, or 10 mass% or less. By limiting the copolymerization ratio of the carboxyl group-containing monomer to a predetermined amount or less, even when the pigment-dispersing master batch for a binder is blended into the binder layer, the pigment can be dispersed well in the layer, and the adhesion reliability can be maintained well. In this embodiment, the content of the carboxyl group-containing monomer may be preferably 7 mass% or less (typically, less than 7 mass%, for example, 6.8 mass% or less or 6.0 mass%) of the monomer component.
The secondary monomer having copolymerizability with the alkyl (meth) acrylate as the main monomer can contribute to introducing crosslinking points into the acrylic polymer or to improving the cohesive force of the acrylic polymer. As the auxiliary monomer, for example, 1 kind or 2 or more kinds of functional group-containing monomers (excluding the above carboxyl group-containing monomers) as described below may be used alone or in combination.
Hydroxyl-containing monomers: hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate; unsaturated alcohols such as vinyl alcohol and allyl alcohol; polypropylene glycol mono (meth) acrylate.
Amide group-containing monomers: such as (meth) acrylamide, N-dimethyl (meth) acrylamide, N-butyl (meth) acrylamide, N-methylol propane (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide.
Amino group-containing monomers: such as aminoethyl (meth) acrylate, N-dimethylaminoethyl (meth) acrylate, t-butylaminoethyl (meth) acrylate.
Monomers having epoxy groups: such as glycidyl (meth) acrylate, methyl glycidyl (meth) acrylate, allyl glycidyl ether.
Cyano-containing monomers: such as acrylonitrile, methacrylonitrile.
Ketone group-containing monomers: such as diacetone (meth) acrylamide, diacetone (meth) acrylate, vinyl methyl ketone, vinyl ethyl ketone, allyl acetoacetate, and vinyl acetoacetate.
Monomers having a ring containing a nitrogen atom: such as N-vinyl-2-pyrrolidone, N-methyl vinyl pyrrolidone, N-vinyl pyridine, N-vinyl piperidone, N-vinyl pyrimidine, N-vinyl piperazine, N-vinyl pyrazine, N-vinyl pyrrole, N-vinyl imidazole, N-vinyl oxazole, N-vinyl morpholine, N-vinyl caprolactam, N- (meth) acryloyl morpholine.
Alkoxysilyl group-containing monomer: such as 3- (meth) acryloxypropyl trimethoxysilane, 3- (meth) acryloxypropyl triethoxysilane, 3- (meth) acryloxypropyl methyldimethoxysilane, 3- (meth) acryloxypropyl methyldiethoxysilane.
In the case where the monomer component constituting the acrylic polymer contains the functional group-containing monomer as described above, the content of the functional group-containing monomer in the monomer component is not particularly limited. The content of the functional group-containing monomer in the monomer component may be, for example, 0.1 mass% or more, and is usually preferably 0.5 mass% or more, and may be 1 mass% or more, from the viewpoint of appropriately exhibiting the effect caused by the use of the functional group-containing monomer. In terms of the relationship with the main monomer and the carboxyl group-containing monomer, the content of the functional group-containing monomer in the monomer component is preferably 40 mass% or less, preferably 20 mass% or less, and may be 10 mass% or less (for example, 5 mass% or less) from the viewpoint of easily achieving a balance of adhesive properties. The techniques disclosed herein may be preferably practiced in a manner such that the monomer component is substantially free of functional group-containing monomers (e.g., such that the monomer component consists essentially of only alkyl (meth) acrylate and carboxyl group-containing monomers). The monomer component substantially free of the functional group-containing monomer means that at least the functional group-containing monomer is not intentionally used, and it is acceptable that the functional group-containing monomer is not intentionally contained in an amount of, for example, 0.05 mass% or less (typically 0.01 mass% or less). The acrylic polymer having the monomer composition can easily disperse the pigment-dispersion master batch for the binder.
The monomer component constituting the acrylic polymer may contain other copolymerized components in addition to the above-mentioned auxiliary monomers for the purpose of improving cohesive force and the like. Examples of the other copolymerizable component include vinyl ester monomers such as vinyl acetate, vinyl propionate and vinyl laurate; aromatic vinyl compounds such as styrene, substituted styrene (α -methylstyrene, etc.), and vinyl toluene; cycloalkyl (meth) acrylates such as cyclohexyl (meth) acrylate, cyclopentyl (meth) acrylate, isobornyl (meth) acrylate, and the like; aromatic ring-containing (meth) acrylates such as aryl (meth) acrylates (e.g., phenyl (meth) acrylate), aryloxyalkyl (meth) acrylates (e.g., phenoxyethyl (meth) acrylate), and arylalkyl (meth) acrylates (e.g., benzyl (meth) acrylate); olefin monomers such as ethylene, propylene, isoprene, butadiene, and isobutylene; chlorine-containing monomers such as vinyl chloride and vinylidene chloride; isocyanate group-containing monomers such as 2- (meth) acryloyloxyethyl isocyanate; an alkoxy group-containing monomer such as methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate; vinyl ether monomers such as methyl vinyl ether and ethyl vinyl ether; and a polyfunctional monomer having 2 or more (for example, 3 or more) polymerizable functional groups (for example, (meth) acryl) in 1 molecule such as 1, 6-hexanediol di (meth) acrylate and trimethylolpropane tri (meth) acrylate.
The amount of the other copolymerizable component is not particularly limited as long as it is appropriately selected according to the purpose and use, and is usually preferably 0.05 mass% or more and may be 0.5 mass% or more from the viewpoint of appropriately exhibiting the effect caused by use. The content of the other copolymerizable component in the monomer component is usually preferably 20 mass% or less, and may be 10 mass% or less (for example, 5 mass% or less) from the viewpoint of easily balancing the adhesive properties. In the present embodiment, the monomer component may be preferably carried out so as to be substantially free of other copolymerizable components. The monomer component substantially not containing the other copolymerizable component means that at least the other copolymerizable component is not intentionally used, and it is acceptable that the other copolymerizable component is not intentionally contained, for example, in an amount of 0.01 mass% or less. The acrylic polymer having the monomer composition can easily disperse the pigment-dispersion master batch for the binder.
The method for obtaining the acrylic polymer is not particularly limited, and various polymerization methods known as a method for synthesizing an acrylic polymer, such as a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, a suspension polymerization method, and a photopolymerization method, may be suitably employed, and a photopolymerization method and a solution polymerization method may be preferably employed.
The initiator used in the polymerization may be appropriately selected from conventionally known thermal polymerization initiators, photopolymerization initiators, and the like, according to the polymerization method. The polymerization initiator may be used singly or in combination of two or more.
For example, in the case of using the photopolymerization method, as the photopolymerization initiator, any appropriate photopolymerization initiator may be used within a range that does not impair the effects of the present invention. The photopolymerization initiator may be 1 or 2 or more.
The photopolymerization initiator is not particularly limited, and for example, a benzoin ether-based photopolymerization initiator, an acetophenone-based photopolymerization initiator, an α -ketol-based photopolymerization initiator, an aromatic sulfonyl chloride-based photopolymerization initiator, a photoactive oxime-based photopolymerization initiator, a benzoin-based photopolymerization initiator, a benzil-based photopolymerization initiator, a benzophenone-based photopolymerization initiator, a ketal-based photopolymerization initiator, a thioxanthone-based photopolymerization initiator, an acylphosphine oxide-based photopolymerization initiator, and the like can be used.
Specific examples of the benzoin ether photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2-dimethoxy-1, 2-diphenylethane-1-one (commercially available products such as trade names "Irgacure 651", manufactured by BASF corporation), anisole methyl ether, and the like.
Specific examples of the acetophenone photopolymerization initiator include 1-hydroxycyclohexyl phenyl ketone (commercially available products such as trade name "Irgacure 184", manufactured by BASF corporation), 4-phenoxydichloroacetophenone, 4-tert-butyl-dichloroacetophenone, 1- [4- (2-hydroxyethoxy) -phenyl ] -2-hydroxy-2-methyl-1-propan-1-one (commercially available products such as trade name "Irgacure 2959", manufactured by BASF corporation), 2-hydroxy-2-methyl-1-phenyl-propan-1-one (commercially available products such as trade name "DAROCURE 1173", manufactured by BASF corporation), and methoxyacetophenone.
The amount of the photopolymerization initiator used is not particularly limited, and may be, for example, in the range of 0.01 to 5 parts by mass, preferably 0.05 to 3 parts by mass, based on 100 parts by mass of the monomer component used for producing the acrylic polymer.
In some embodiments, the acrylic polymer may be included in the colored adhesive composition for forming the colored adhesive layer in the form of a partial polymer (acrylic polymer syrup) obtained by polymerizing a part of the monomer components by irradiating ultraviolet rays to a mixture in which a polymerization initiator is mixed in the monomer components. The colored adhesive composition containing the acrylic polymer syrup is applied to a predetermined object to be coated, and ultraviolet rays are irradiated, whereby polymerization can be completed. That is, the acrylic polymer syrup can be grasped in the form of a precursor of the acrylic polymer. The pressure-sensitive adhesive layer disclosed herein contains an acrylic polymer as a base polymer in the form of, for example, the acrylic polymer syrup, and may be formed using a colored pressure-sensitive adhesive composition containing an appropriate amount of a polyfunctional monomer, if necessary.
The polymerization temperature, polymerization solvent, and initiator used in the polymerization, which are preferable in the case of using the solution polymerization method, are as described in the item of the resin (a).
According to the above solution polymerization, a polymerization reaction liquid in which an acrylic polymer is dissolved in an organic solvent can be obtained. The colored adhesive composition forming the adhesive layer in the present embodiment may contain the above-mentioned polymerization reaction liquid or an acrylic polymer solution obtained by subjecting the reaction liquid to an appropriate post-treatment. As the acrylic polymer solution, a solution obtained by adjusting the polymerization reaction solution to an appropriate viscosity (concentration) as needed can be used. Alternatively, an acrylic polymer solution prepared by synthesizing an acrylic polymer by a polymerization method other than solution polymerization (for example, emulsion polymerization, photopolymerization, bulk polymerization, or the like) and dissolving the acrylic polymer in an organic solvent may also be used.
(other Components)
[ dispersibility-improving ingredient ]
The colored adhesive composition of the present embodiment may further contain a component that contributes to the improvement of dispersibility of the pigment dispersion master batch for adhesive. The dispersibility enhancing component may be, for example, a polymer, an oligomer, a liquid resin, a surfactant, or the like. The above-mentioned dispersibility enhancing component is preferably dissolved in the base polymer composition. The oligomer may be, for example, a low molecular weight polymer (for example, mw of less than 10X 10) containing 1 or 2 or more monomer components in the acrylic monomer as exemplified above 4 Preferably less than 5 x 10 4 Acrylic oligomer of (a) and (b). The liquid resin may be, for example, a tackifying resin having a softening point of 50 ℃ or less, more preferably 40 ℃ or less (typically, a tackifying resin such as rosin-based, terpene-based, hydrocarbon-based, etc., for example, hydrogenated rosin methyl ester, etc.). Such dispersibility-enhancing component can suppress dispersion unevenness of the pigment, and further can suppress color unevenness of the adhesive layer formed of the colored adhesive composition. Therefore, an adhesive layer having a better appearance quality can be formed.
The content of the dispersibility-enhancing component is not particularly limited, and is generally preferably 20 mass% or less (preferably 10 mass% or less, more preferably 7 mass% or less, for example 5 mass% or less) of the entire colored adhesive composition (adhesive layer) from the viewpoint of suppressing the influence on the adhesive properties (for example, the decrease in the aggregation). In one embodiment, the content of the dispersibility-enhancing component may be 10 times or less (preferably 5 times or less, for example, 3 times or less) the mass of the pigment-dispersion master batch for a binder. On the other hand, from the viewpoint of suitably exhibiting the effect of the dispersibility-improving component, the content thereof is usually preferably 0.2 mass% or more (typically 0.5 mass% or more, preferably 1 mass% or more) of the entire colored adhesive composition. In one embodiment, the content of the dispersibility-enhancing component may be 0.2 times or more (preferably 0.5 times or more, for example, 1 time or more) the mass of the pigment-dispersion master batch for a binder.
[ tackifying resin ]
The colored adhesive composition of the present embodiment may contain a tackifying resin. This can improve the adhesion reliability between the pressure-sensitive adhesive layer formed from the colored pressure-sensitive adhesive composition and the pressure-sensitive adhesive sheet. As the tackifying resin, 1 or 2 or more kinds of publicly known various tackifying resins selected from the group consisting of phenol-based tackifying resins, terpene-based tackifying resins, modified terpene-based tackifying resins, rosin-based tackifying resins, hydrocarbon-based tackifying resins, epoxy-based tackifying resins, polyamide-based tackifying resins, elastomer-based tackifying resins, ketone-based tackifying resins and the like can be used.
Examples of the phenolic tackifying resins include terpene phenolic resins, hydrogenated terpene phenolic resins, alkyl phenolic resins, and rosin phenolic resins.
The terpene phenol resin is a polymer containing a terpene residue and a phenol residue, and is a concept including both a copolymer of a terpene and a phenol compound (terpene-phenol copolymer resin) and a substance obtained by phenol-modifying a terpene homopolymer or copolymer (phenol-modified terpene resin). Suitable examples of terpenes constituting such terpene phenolic resins include monoterpenes such as α -pinene, β -pinene, and limonene (including d-isomer, l-isomer, and d/l-isomer (dipentene)). The hydrogenated terpene phenol resin is a hydrogenated terpene phenol resin having a structure obtained by hydrogenating such a terpene phenol resin. Sometimes also referred to as hydrogenated terpene phenolic resins.
The alkylphenol resin is a resin (oleophenol resin) obtained from alkylphenol and formaldehyde. Examples of the alkylphenol resin include novolac-type and resol-type substances.
Typically, rosin phenolic resins are phenolic modifications of rosins or of the various rosin derivatives described above (including rosin esters, unsaturated fatty acid modified rosins and unsaturated fatty acid modified rosin esters). Examples of the rosin phenol resin include rosin phenol resins obtained by adding phenol to rosin or the above-mentioned various rosin derivatives using an acid catalyst and performing thermal polymerization.
Examples of the terpene-based tackifying resin include polymers of terpenes (typically, monoterpenes) such as α -pinene, β -pinene, d-limonene, l-limonene, dipentene, and the like. The terpene may be 1 kind of homopolymer or 2 or more kinds of terpene copolymer. Examples of homopolymers of 1 terpene include α -pinene polymers, β -pinene polymers, dipentene polymers, and the like. Examples of the modified terpene resin include those obtained by modifying the terpene resin. Specifically, styrene-modified terpene resins, hydrogenated terpene resins, and the like can be exemplified.
The term rosin-based tackifying resin as used herein includes both rosin-based and rosin derivative resins. Examples of the rosins include unmodified rosins (raw rosins) such as rosin, wood rosin, tall oil rosin, and the like; modified rosins (hydrogenated rosins, disproportionated rosins, polymerized rosins, other chemically modified rosins, etc.) modified by hydrogenation, disproportionation, polymerization, etc. of these unmodified rosins.
Typically, the rosin derivative resin is a rosin derivative as described above. The term rosin-based resin as referred to herein includes derivatives of unmodified rosin and derivatives of modified rosin (including hydrogenated rosin, disproportionated rosin and polymerized rosin). Examples thereof include rosin esters such as unmodified rosin esters which are esters of unmodified rosin and alcohols, and modified rosin esters which are esters of modified rosin and alcohols; for example, unsaturated fatty acid-modified rosins obtained by modifying rosins with unsaturated fatty acids; for example, unsaturated fatty acid-modified rosin esters obtained by modifying rosin esters with unsaturated fatty acids; for example, rosin alcohols obtained by reducing carboxyl groups of rosins or various rosin derivatives (including rosin esters, unsaturated fatty acid-modified rosins and unsaturated fatty acid-modified rosin esters) described above; for example, rosin or metal salts of various rosin derivatives described above. Specific examples of rosin esters include methyl esters, triethylene glycol esters, glycerol esters, pentaerythritol esters, and the like of unmodified or modified rosins (hydrogenated rosins, disproportionated rosins, polymerized rosins, and the like).
Examples of the hydrocarbon-based tackifying resin include various hydrocarbon-based resins such as aliphatic hydrocarbon resins, aromatic hydrocarbon resins, aliphatic cyclic hydrocarbon resins, aliphatic/aromatic petroleum resins (styrene-olefin copolymers and the like), aliphatic/alicyclic petroleum resins, hydrogenated hydrocarbon resins, coumarone-based resins, coumarone-indene-based resins and the like.
The softening point of the tackifying resin is not particularly limited. From the viewpoint of improving the cohesive force, in one embodiment, a tackifying resin having a softening point (softening temperature) of 80 ℃ or higher (preferably 100 ℃ or higher) can be preferably used. The technology disclosed herein can be preferably carried out by setting the total amount of the tackifying resins contained in the adhesive layer to 100 mass%, in which more than 50 mass% (more preferably more than 70 mass%, for example more than 90 mass%) is the tackifying resin having the above softening point. For example, a phenol tackifying resin (terpene phenol resin or the like) having such a softening point can be preferably used. The tackifying resin may comprise, for example, a terpene phenolic resin having a softening point of 135 ℃ or higher (further 140 ℃ or higher). The upper limit of the softening point of the tackifying resin is not particularly limited. In one embodiment, a tackifying resin having a softening point of 200 ℃ or less (more preferably 180 ℃ or less) is preferably used from the viewpoint of improving adhesion to an adherend. In a preferred embodiment, the tackifying resin (typically a terpene phenolic resin) has a softening point of less than 130 ℃, for example less than 120 ℃. In this way, by using a tackifying resin having a relatively low softening point, for example, dispersibility of pigment can be improved. The softening point of the tackifying resin can be measured according to the softening point test method (ring and ball method) specified in JIS K2207.
As a preferred embodiment, the tackifying resin contains 1 or 2 or more phenolic tackifying resins (typically, terpene phenolic resins). The technique disclosed herein can be preferably carried out by, for example, setting 25 mass% or more (more preferably 30 mass% or more) of the total amount of the tackifying resin to 100 mass% as a terpene phenolic resin. The terpene phenolic resin may be 50 mass% or more of the total amount of the tackifying resin, or 80 mass% or more (for example, 90 mass% or more). The terpene phenolic resin may be substantially the entire (for example, 95 to 100 mass%, and further 99 to 100 mass%) of the tackifying resin.
In the case where the colored adhesive composition forming the adhesive layer contains a tackifying resin, the amount of the tackifying resin is not particularly limited, and may be appropriately set in the range of 1 to 100 parts by mass with respect to 100 parts by mass of the base polymer, for example. The amount of the colored tackifying resin to be used is usually preferably 5 parts by mass or more, preferably 10 parts by mass or more, and may be 15 parts by mass or more, based on 100 parts by mass of the base polymer (for example, acrylic polymer), from the viewpoint of suitably exerting the effect of improving the peel strength. For example, in the binder layer containing a pigment, a predetermined amount of a tackifying resin (for example, a terpene phenolic resin having a softening point of 120 ℃ or less) is contained, and thus the dispersibility of the pigment tends to be improved. The amount of the colored tackifying resin to be used is usually 50 parts by mass or less, 40 parts by mass or less, or 30 parts by mass or less based on 100 parts by mass of the base polymer (for example, acrylic polymer) from the viewpoint of heat-resistant cohesive force.
[ Cross-linking agent ]
The colored adhesive composition forming the adhesive layer of the present embodiment may contain a crosslinking agent as needed. The type of the crosslinking agent is not particularly limited, and may be appropriately selected from conventionally known crosslinking agents. Examples of such a crosslinking agent include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, oxazoline-based crosslinking agents, aziridine-based crosslinking agents, melamine-based crosslinking agents, peroxide-based crosslinking agents, urea-based crosslinking agents, metal alkoxide-based crosslinking agents, metal chelate-based crosslinking agents, metal salt-based crosslinking agents, carbodiimide-based crosslinking agents, hydrazine-based crosslinking agents, amine-based crosslinking agents, and silane-based coupling agents. The crosslinking agent may be used alone or in combination of 1 or more than 2.
The total amount of the crosslinking agent is not particularly limited. For example, the amount of the polymer is 10 parts by mass or less, preferably 0.005 to 10 parts by mass, and more preferably 0.01 to 5 parts by mass, based on 100 parts by mass of the base polymer (preferably an acrylic polymer).
The colored adhesive composition forming the adhesive layer may contain various additives which are common in the adhesive field, such as leveling agents, crosslinking aids, plasticizers, softeners, antistatic agents, antioxidants, ultraviolet absorbers, antioxidants, light stabilizers, and the like, as needed. As for such various additives, conventionally known ones can be used by a conventional method, and since the present invention is not particularly characterized, detailed description thereof is omitted.
The pressure-sensitive adhesive layer of the present embodiment is not particularly limited as long as it is formed of the colored pressure-sensitive adhesive composition of the present embodiment, and may be formed of an aqueous pressure-sensitive adhesive composition, a solvent-based pressure-sensitive adhesive composition, a hot-melt pressure-sensitive adhesive composition, or an active energy ray-curable pressure-sensitive adhesive composition. The aqueous adhesive composition is an adhesive composition comprising a form of an adhesive (adhesive layer forming component) in a solvent (aqueous solvent) containing water as a main component, and typically includes an adhesive composition called a water-dispersible adhesive composition (a composition in which at least a part of the adhesive is dispersed in water) or the like. The solvent-type adhesive composition is an adhesive composition in a form containing an adhesive in an organic solvent. From the viewpoint of adhesive properties and the like, the present embodiment can be preferably implemented by providing an adhesive layer formed of a solvent-based adhesive composition.
In the case where the adhesive layer has a multilayer structure of two or more layers, the adhesive layer can be produced by bonding the adhesive layers formed in advance. Alternatively, the second adhesive layer may be formed by applying an adhesive composition to a preformed first adhesive layer and curing the adhesive composition, as long as at least one of the adhesive compositions is a colored adhesive composition according to an embodiment of the present invention. In the case where the pressure-sensitive adhesive layer included in the pressure-sensitive adhesive sheet to be described later used in the mode of adhering the pressure-sensitive adhesive sheet to an adherend and then photo-curing the pressure-sensitive adhesive sheet is a multilayer structure, the photo-curable pressure-sensitive adhesive layer may be a part (for example, one layer) or all of the layers included in the multilayer structure.
In the case of applying the colored adhesive composition to form the adhesive layer, the application may be performed using a conventional coater such as a gravure roll coater, a reverse roll coater, a kiss roll coater, a dip roll coater, a bar coater, a knife coater, or a spray coater. In the pressure-sensitive adhesive sheet having a form of a substrate, as a method for providing the pressure-sensitive adhesive layer on the substrate, a direct method of directly supplying a colored pressure-sensitive adhesive composition to the substrate to form the pressure-sensitive adhesive layer, or a transfer method of transferring the pressure-sensitive adhesive layer formed on the release surface to the substrate may be used.
The thickness of the pressure-sensitive adhesive layer is not particularly limited, and may be, for example, 3 μm to 2000 μm. In terms of adhesion to an adherend such as step-and-step followability, the thickness of the pressure-sensitive adhesive layer may be, for example, 5 μm or more, preferably 10 μm or more, more preferably 20 μm or more, and still more preferably 30 μm or more in several embodiments. The thickness of the adhesive layer may be 50 μm or more, may exceed 50 μm, may be 70 μm or more, may be 100 μm or more, and may be 120 μm or more. In addition, from the viewpoint of preventing the occurrence of residual glue due to cohesive failure of the adhesive layer, in several embodiments, the thickness of the adhesive layer may be 1000 μm or less, 700 μm or less, 500 μm or less, 300 μm or less, 200 μm or less, or 170 μm or less, for example. The technique described in this embodiment can be suitably applied in the form of an adhesive sheet described later, in which the thickness of the adhesive layer is 130 μm or less, 90 μm or less, or 60 μm or less (for example, 40 μm or less). In the pressure-sensitive adhesive sheet described later including a pressure-sensitive adhesive layer having a multilayer structure of two or more layers, the thickness of the pressure-sensitive adhesive layer is the thickness from the pressure-sensitive adhesive surface to the surface opposite to the pressure-sensitive adhesive surface.
< adhesive sheet >
The pressure-sensitive adhesive sheet according to the embodiment of the present invention includes a pressure-sensitive adhesive layer (colored pressure-sensitive adhesive) formed of the colored pressure-sensitive adhesive composition. That is, the pressure-sensitive adhesive sheet according to the embodiment of the present invention includes the pressure-sensitive adhesive layer formed of the colored pressure-sensitive adhesive composition. The pressure-sensitive adhesive sheet of the present embodiment may be a pressure-sensitive adhesive sheet with a base material in the form of a pressure-sensitive adhesive layer on one side (fig. 2) or both sides (fig. 3) of a sheet-like base material (support), or may be a pressure-sensitive adhesive sheet without a base material in the form of a pressure-sensitive adhesive layer held on a release liner or the like. In the concept of the adhesive sheet mentioned herein, an object called an adhesive tape, an adhesive label, an adhesive film, or the like may be included.
The pressure-sensitive adhesive layer is typically formed continuously, but is not limited to this form, and may be formed in a regular pattern such as dots or stripes, or in a random pattern. The pressure-sensitive adhesive sheet of the present embodiment may be rolled or formed into a single sheet. Alternatively, the pressure-sensitive adhesive sheet may be further processed into various shapes.
From the viewpoint of having the step-and-step following property, the pressure-sensitive adhesive sheet of the present embodiment may be of a base-free type (pressure-sensitive adhesive layer) having no base material as shown in fig. 1. When the object to which the adhesive sheet is to be attached has a step (for example, 10 μm), the adhesive sheet can be attached along the step by providing the adhesive sheet with step following property. Thus, the pressure-sensitive adhesive sheet can be adhered to the object without any gap.
The pressure-sensitive adhesive sheet of the present embodiment may include a support base material as shown in fig. 2. Thus, the adhesive sheet can be processed with good accuracy by punching or the like. Such an adhesive sheet is preferable for use in applications in which the adhesive sheet is processed into a specific shape or is used by being thinned. The thickness of the support substrate in this embodiment is, for example, less than 75 μm. The support substrate having a limited thickness can be preferably used for applications requiring thickness reduction and weight reduction. Further, by limiting the thickness of the support substrate and relatively increasing the thickness of the pressure-sensitive adhesive layer, for example, adhesion characteristics such as adhesion reliability can be improved. From this viewpoint, the thickness of the support base is preferably 60 μm or less, more preferably 50 μm or less (for example, less than 50 μm), further preferably 40 μm or less, particularly preferably 30 μm or less (for example, less than 30 μm, typically 25 μm or less). In one embodiment, the thickness of the support substrate may be 20 μm or less, may be 12 μm or less, and may be 7 μm or less (e.g., 3 μm or less). The lower limit of the thickness of the support substrate is not particularly limited. The thickness of the support base is usually 0.5 μm or more (for example, 1 μm or more) from the viewpoints of handling property (handleability), workability, and the like of the adhesive sheet. In one embodiment, the thickness of the support substrate may be 3 μm or more. In another embodiment, the thickness of the support substrate may be 8 μm or more, 13 μm or more, or 16 μm or more.
The structure and material of the support substrate are not particularly limited, but are typically film-like substrates (also referred to as "substrate films"). As the base film, a film containing a resin film as a base film can be preferably used. Typically, the base film is a member (independent) capable of maintaining its shape independently. The base film in this embodiment may be substantially composed of such a base film. Alternatively, the base film may include an auxiliary layer in addition to the base film. Examples of the auxiliary layer include a colored layer, a reflective layer, an undercoat layer, and an antistatic layer provided on the surface of the base film.
The resin film is a film containing a resin material as a main component (for example, a component in an amount of more than 50% by mass in the resin film). Examples of the resin film include polyolefin resin films such as Polyethylene (PE), polypropylene (PP) and ethylene-propylene copolymers; polyester resin films such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN); a polyurethane resin film; a vinyl chloride resin film; a vinyl acetate resin film; a polyimide resin film; a polyamide resin film; a fluororesin film; cellophane, and the like. The resin film may be a rubber film such as a natural rubber film or a butyl rubber film. Among them, from the viewpoint of handleability and workability, a polyester film is preferable, and among them, a PET film is particularly preferable. In the present specification, the term "resin film" is typically a non-porous sheet, and is a concept distinguished from so-called nonwoven fabric or woven fabric (in other words, a concept other than woven fabric or woven fabric).
The base film may be blended with various additives such as a filler (inorganic filler, organic filler, etc.), a dispersant (surfactant, etc.), an antioxidant, an ultraviolet absorber, an antistatic agent, a lubricant, a plasticizer, etc., as needed. The compounding ratio of the respective additives is generally less than 30 mass% (e.g., less than 20 mass%, typically less than 10 mass%).
The surface of the base film may be subjected to conventionally known surface treatments such as corona discharge treatment, plasma treatment, ultraviolet irradiation treatment, acid treatment, alkali treatment, and primer coating. Such a surface treatment may be a treatment for improving the adhesion between the substrate film and the adhesive layer, in other words, the anchoring property of the adhesive layer to the substrate film. In addition, when the technology disclosed herein is implemented in the form of a single-sided pressure-sensitive adhesive sheet with a base material, the back surface of the base material film may be subjected to a peeling treatment as needed. Typically, the stripping treatment may be a treatment of supplying a stripping treatment agent such as a general silicone-based, long-chain alkyl-based, fluorine-based, or the like in a film form of 0.01 μm to 1 μm (for example, 0.01 μm to 0.1 μm). By performing the peeling treatment, the effect of easily unwinding the roll of the adhesive sheet into a roll can be obtained.
In the pressure-sensitive adhesive sheet of the present embodiment, a release liner may be used in the formation of the pressure-sensitive adhesive layer, the production of the pressure-sensitive adhesive sheet, the storage of the pressure-sensitive adhesive sheet before use, the distribution, the shape processing, and the like. The release liner is not particularly limited, and for example, a release liner having a release treatment layer on the surface of a liner substrate such as a resin film or paper; and release liners made of a low-adhesion material such as a fluorine-based polymer (polytetrafluoroethylene or the like) or a polyolefin-based resin (polyethylene, polypropylene or the like). The release treatment layer may be formed by surface-treating the gasket base material with a release treatment agent such as silicone, long-chain alkyl, fluorine, molybdenum sulfide, or the like.
(thickness of adhesive sheet)
The total thickness of the pressure-sensitive adhesive sheet (including the pressure-sensitive adhesive layer, and further including the support substrate in the structure having the support substrate, but not including the release liner) of the present embodiment is not particularly limited. From the viewpoint of thickness reduction, the total thickness of the pressure-sensitive adhesive sheet is usually preferably 200 μm or less. The lower limit of the thickness of the pressure-sensitive adhesive sheet is not particularly limited, and may be generally 1 μm or more, for example, 3 μm or more, preferably 6 μm or more, more preferably 10 μm or more (for example, 15 μm or more), as appropriate.
In a preferred embodiment, the total thickness of the pressure-sensitive adhesive sheet is 150 μm or less, more preferably 120 μm or less, still more preferably 70 μm or less, particularly preferably 50 μm or less (for example, 40 μm or less), for example, 35 μm or less, 25 μm or less, further 15 μm or less (for example, 7 μm or less). In the structure using such a pressure-sensitive adhesive sheet having a small thickness, the light-shielding effect achieved by the present embodiment can be preferably exhibited.
The proportion of the total thickness of the adhesive layer contained in the adhesive sheet to the total thickness of the adhesive sheet is not particularly limited. Here, the total thickness of the adhesive layer contained in the adhesive sheet means: the total thickness of the adhesive layer provided on one surface of the substrate film and the adhesive layer provided on the other surface. In the case of a single-sided adhesive sheet in which an adhesive layer is provided only on one surface of a base film, the thickness of the adhesive layer provided on the other surface is zero, and the thickness of the adhesive layer provided on the one surface is identical to the total thickness of the adhesive layers. The technique disclosed herein can be carried out, for example, such that the total thickness of the adhesive layer is 40% or more (preferably 50% or more, typically more than 50%, more preferably 60% or more, still more preferably 70% or more) of the total thickness of the adhesive sheet. In one embodiment, the total thickness of the adhesive layer may be 75% or more, and further 80% or more of the total thickness of the adhesive sheet. The upper limit of the proportion of the total thickness of the pressure-sensitive adhesive layer to the total thickness of the pressure-sensitive adhesive sheet is not particularly limited, and is usually preferably 95% or less, and more preferably 90% or less.
Examples of applications of the adhesive layer and the adhesive sheet according to the present embodiment include applications to furniture such as housings of electronic devices, structural members for vehicles, vehicle mounted products, housings of home appliances, structural members, mechanical members, various automobile members, electronic device members, furniture, kitchen products, medical devices, building material members, other structural members, and exterior packaging members.
More specifically, examples of the electronic device and the home electric device include home electric products such as a refrigerator, a washing machine, a vacuum cleaner, a microwave oven, an air conditioner, a lighting device, an electric water heater, a television, a timepiece, a ventilator, a projector, and a speaker; personal computers, portable telephones, smart phones, digital cameras, tablet PCs, portable music players, portable game players, chargers, batteries, and other electronic information devices.
In the vehicle aspect, there may be mentioned a dashboard, a console box, a door handle, a door trim, a shift lever, a tray type, a storage box, a bumper, an engine cover, a fender, a trunk, a door, a roof, a pillar, a seat, a steering wheel, an ECU box, an electric component, an engine surrounding component, a drive system/gear surrounding component, an intake/exhaust system component, a cooling system component, and the like.
Examples
The present invention will be described more specifically below by way of examples and comparative examples, but the present invention is not limited to the examples. In the following description, "parts" and "%" are mass references unless otherwise specified.
< evaluation method >
[ measurement of median particle diameter of pigment-dispersed particles ]
As a method for measuring the median particle diameter, a laser diffraction/scattering type particle diameter distribution measuring apparatus LA-950 (manufactured by horiba ltd.) was used, and ethyl acetate was used as a dispersion medium for measurement. The relative refractive index was calculated from the refractive index of each of ethyl acetate and the pigment used and measured, whereby the dispersed particles of the pigment in the dispersion liquid were measured. The median particle diameter of the dispersed particles of the pigment in the dispersion is obtained from the measurement result.
[ Standard deviation of transmittance ]
The polyester film a of the adhesive sheets of examples and comparative examples was peeled off and attached to a carrier sheet (trade name "S1112", manufactured by songawa corporation) by a manual roll. The light transmittance of the obtained glass sample at a wavelength of 300nm to 800nm was measured by an ultraviolet-visible-near infrared spectrophotometer ("UH 4150", manufactured by Hitachi Ltd.). From the obtained transmittance spectrum, transmittance at a wavelength at which transmittance at 400 to 800nm becomes lowest is obtained.
For each sample, 10-point measurement was performed, and the standard deviation σ was calculated for the transmittance at 560nm of 10 points, and the color unevenness in the surface of the adhesive layer was evaluated. The standard deviation σ was evaluated as o when it was less than 1.2, and the standard deviation σ was evaluated as x when it was not less than 1.2.
[ adhesion reliability ]
For the adhesive sheets of examples and comparative examples, peel adhesion test was performed according to JIS Z0237:2009, whereby adhesion was evaluated.
Specifically, a PET film having a thickness of 25 μm was stuck to one surface of a double-sided pressure-sensitive adhesive sheet at a temperature of 23℃and a relative humidity of 50% RH, and the resultant was subjected to a backing, and cut into a width of 20mm to prepare a measurement sample. The other adhesive surface of the measurement sample was adhered to a glass plate as an adherend with an adhesive area of 20mm in width and 100mm in length by one round trip of a 2kg roller. The measurement sample thus stuck to the adherend was left for 30 minutes. Thereafter, the force (N/20 mm) at a peeling angle of 180℃and a measuring speed of 300mm/min at which the measurement sample was peeled from the adherend was measured.
The separately prepared measurement sample was left for 500 hours at a temperature of 85℃and a relative humidity of 85%. Thereafter, the adhesive force was measured by the same method.
The change rate of the adhesive force before and after leaving under an environment at a temperature of 85 ℃ and a relative humidity of 85% was calculated by the following calculation formula, and the case where the change rate was 100 (%) or more was marked as "o", and the case where it was less than 100 (%) was marked as "x", and was used as an evaluation of the adhesion reliability.
Rate of change (%) = (adhesion after placement-adhesion before placement)/(adhesion before placement) ×100
Preparation of (meth) acrylic Polymer
100 parts by mass of toluene, 60 parts by mass of dicyclohexyl methacrylate (DCPMA) (trade name: FA-513M, manufactured by Hitachi chemical industry Co., ltd.), 40 parts by mass of Methyl Methacrylate (MMA) and 3.5 parts by mass of alpha-Thioglycerol (TGR) as a chain transfer agent were charged into a four-necked flask. Then, after stirring at 70℃for 1 hour under a nitrogen atmosphere, 0.2 parts by mass of azobisisobutyronitrile as a thermal polymerization initiator was charged, and reacted at 70℃for 2 hours, followed by reacting at 80℃for 2 hours. Thereafter, the reaction solution was charged under a temperature atmosphere of 130℃and toluene, a chain transfer agent and unreacted monomers were removed by drying to obtain a solid (meth) acrylic polymer. The glass transition temperature of the obtained (meth) acrylic polymer was 144℃and the weight-average molecular weight was 4300.
< preparation of photopolymerizable composition (adhesive composition)
2-ethylhexyl acrylate (78 parts by mass), N-vinyl-2-pyrrolidone (18 parts by mass) and hydroxyethyl acrylate (4 parts by mass), 2-dimethoxy-1, 2-diphenyl-1-one (trade name "Irgacure 651", manufactured by CIBAJAPAN Co., ltd.) (0.035 parts by mass) and 1-hydroxy-cyclohexyl-phenyl-one (trade name "Irgacure 184", manufactured by CIBAJAPAN Co., ltd.) (0.035 parts by mass) as monomer components were charged into a four-necked flask equipped with a stirrer, a thermometer, a nitrogen inlet pipe, a reflux condenser and a dropping funnel, and were exposed to ultraviolet rays under a nitrogen atmosphere to perform partial photopolymerization, thereby obtaining a partial polymer (monomer slurry).
To this partial polymer (100 parts by mass), 1, 6-hexanediol diacrylate (0.088 parts by mass), the (meth) acrylic polymer (11.8 parts by mass), and gamma-glycidoxypropyl trimethoxysilane (KBM-403, manufactured by Xinyue silicone company, 0.35 parts by mass) were added and then uniformly mixed to prepare a photopolymerizable composition (adhesive composition).
< preparation of adhesive composition 1 >
In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser and a nitrogen inlet tube, a mixture comprising 60 parts by mass of N-butyl acrylate, 18 parts by mass of 4-hydroxybutyl acrylate, 22 parts by mass of N-vinylpyrrolidone, 0.2 part by mass of 2,2' -Azobisisobutyronitrile (AIBN) as a polymerization initiator and 122 parts by mass of ethyl acetate as a solvent was stirred at 60℃under a nitrogen atmosphere for 7 hours (polymerization). Thus, a polymer solution containing an acrylic polymer was obtained. The weight average molecular weight (Mw) of the acrylic polymer in the polymer solution was 40 ten thousand.
< preparation of adhesive composition 2 >
In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser and a nitrogen inlet tube, a mixture comprising 96 parts by mass of 2-ethylhexyl acrylate, 4 parts by mass of 2-hydroxyethyl acrylate, 0.2 part by mass of 2,2' -Azobisisobutyronitrile (AIBN) as a polymerization initiator and 122 parts by mass of ethyl acetate as a solvent was stirred at 60 ℃ under a nitrogen atmosphere for 7 hours (polymerization reaction). Thus, a polymer solution containing an acrylic polymer was obtained. The weight average molecular weight (Mw) of the acrylic polymer in the polymer solution was 60 ten thousand.
< preparation of masterbatch resin 1 >
47 parts by mass of toluene was charged into the autoclave, replaced with nitrogen, and then heated to 140℃under stirring in a sealed state. While the temperature in the autoclave was controlled to 105 ℃, a mixed solution of 20 parts by mass of methyl acrylate, 68 parts by mass of 2-ethylhexyl acrylate, 10 parts by mass of N-vinyl-2-pyrrolidone, 2 parts by mass of acrylic acid (all manufactured by Tokyo chemical industry Co., ltd.), 1 part by mass of PERBUTYL O (manufactured by Japanese fat & oil Co., ltd.) and 80 parts by mass of xylene was polymerized for 3 hours. Thereafter, the reaction was carried out at 175℃for 1 hour. Thereafter, desolventizing was performed at 170 ℃ to obtain a master batch resin 1.
< preparation of masterbatch resin 2 >
A masterbatch resin 2 was obtained in the same manner as the masterbatch resin 1 except that the composition of the monomer was changed as shown in table 1.
< preparation of masterbatch resin 3 >
A masterbatch resin 3 was obtained in the same manner as the masterbatch resin 1 except that the composition of the monomer was changed as shown in table 1.
< preparation of masterbatch resin 4 >
47 parts by mass of toluene was charged into the autoclave, replaced with nitrogen, and then heated to 140℃under stirring in a sealed state. While the temperature in the autoclave was controlled to 105 ℃, a mixed solution of 15 parts by mass of methyl acrylate, 71 parts by mass of 2-ethylhexyl acrylate, 12 parts by mass of N-vinyl-2-pyrrolidone, 2 parts by mass of acrylic acid (all manufactured by Tokyo chemical industry Co., ltd.), 1 part by mass of PERBUTYL O (manufactured by Japanese fat & oil Co., ltd.) and 80 parts by mass of xylene was polymerized for 3 hours. Thereafter, the reaction was carried out at 175℃for 1 hour. Thereafter, desolventizing was performed at 170 ℃ to obtain a master batch resin 4.
< preparation of masterbatch resin 5 >
47 parts by mass of toluene was charged into the autoclave, replaced with nitrogen, and then heated to 140℃under stirring in a sealed state. The mixed solution of 30 parts by mass of methyl acrylate, 68 parts by mass of 2-ethylhexyl acrylate, 2 parts by mass of acrylic acid (all manufactured by tokyo chemical industry Co., ltd.), 1 part by mass of PERBUTYL O (manufactured by Japanese fat and oil Co., ltd.) and 90 parts by mass of xylene was polymerized while controlling the temperature in the autoclave to 105℃and taking 3 hours. Thereafter, the reaction was carried out at 175℃for 1 hour. Thereafter, desolventizing was performed at 170 ℃ to obtain a master batch resin 5.
The monomer compositions, tg and acid numbers of the masterbatch resins 1 to 5 are shown in Table 1. The weight average molecular weights (Mw) and the number average molecular weights (Mn) of the masterbatch resins 1 to 5 are also shown in Table 1.
TABLE 1
Production example 1 production of pigment Dispersion 1
175 parts by mass of the master batch resin prepared as described above as the binder pigment dispersion master batch resin and 25 parts by mass of the magenta pigment (pigment red 122) were kneaded by using PLASTIL (manufactured by Toyo Seisakusho Co., ltd.), 72 parts by mass of the obtained pigment dispersion resin and 28 parts by mass of 2-ethylhexyl acrylate were mixed and dissolved in advance, and the mixture was put into a container for a sand mill, and 120g of 0.4mm phi glass beads were added and dispersed. The dispersion particle diameter of the pigment was measured by a laser diffraction/scattering particle diameter distribution measuring device LA-950, and the dispersion was ended at the time point when the change was no longer made, and the glass beads were removed, to obtain a pigment dispersion liquid 1. The median particle diameter of the dispersed particles of the pigment in the pigment dispersion liquid 1 was 100nm.
Production example 2 production of pigment Dispersion 2
28 parts by mass of 2-ethylhexyl acrylate, 1 part by mass of the master batch resin prepared as described above as a pigment dispersion master batch resin for a binder, and 18 parts by mass of a magenta pigment (pigment red 122) were mixed and dissolved in advance, and put into a container for a sand mill, and 120g of 0.4mm phi glass beads were added and dispersed. The dispersion particle diameter of the pigment was measured by a laser diffraction/scattering particle diameter distribution measuring device LA-950, and the dispersion was ended at the time point when the change was no longer made, and the glass beads were removed, to obtain a pigment dispersion liquid 2. The median particle diameter of the dispersed particles of the pigment in the pigment dispersion liquid 2 was 800nm.
Production example 3 production of pigment Dispersion 3
54 parts by mass of pigment dispersant 1 (trade name "FLOWLEN DOPA15BHFS", manufactured by co-Rong corporation) and 18 parts by mass of magenta pigment (pigment red 122) were mixed in advance to form a uniform paste, 28 parts by mass of 2-ethylhexyl acrylate was added thereto, and the mixture was put into a container for a sand mill, and 120g of 0.4mm phi glass beads were added thereto to disperse the mixture. The dispersion particle diameter of the pigment was measured by a laser diffraction/scattering particle diameter distribution measuring device LA-950, and the dispersion was ended at the time point when the change was no longer made, and the glass beads were removed, to obtain a pigment dispersion liquid 3. The median particle diameter of the dispersed particles of the pigment in the pigment dispersion liquid 3 was 100nm.
PREPARATION EXAMPLE 4 preparation of pigment Dispersion 4
Pigment dispersion 4 was obtained in the same manner as in production example 3 except that pigment dispersion 1 was changed to dispersion 2 (trade name "DIPER BYK-145", manufactured by BYK-Chemie Japan BYK Co.). The median particle diameter of the dispersed particles of the pigment in the pigment dispersion liquid 4 was 100nm.
PREPARATION EXAMPLE 5 preparation of pigment Dispersion 5
Pigment dispersion 5 was obtained in the same manner as in production example 3 except that the magenta pigment (pigment red 122) was changed to a black pigment (pigment black 7) and 2-ethylhexyl acrylate was changed to ethyl acetate. The median particle diameter of the dispersed particles of the pigment in the pigment dispersion liquid 5 was 100nm.
< examples and comparative examples >
(preparation of micro master batch 1 (MMB 1))
Masterbatch resin 1 (75 parts by mass) and a magenta pigment (pigment red 122) (25 parts by mass) were introduced into a stirrer unit using a LABO-PLASTIL (roll stirrer R60) manufactured by Toyo Severe Co., ltd, and kneaded at 100℃and 150 rpm. The pigment dispersion thus sampled was dissolved and dispersed in ethyl acetate, and the dispersed particle diameter of the pigment was measured by a laser diffraction/scattering particle diameter distribution measuring device LA-950, and the dispersion was ended at the point of no change, to obtain a pigment dispersion micro master batch (MMB 1) for a binder of example.
(preparation of micro master batch 2 (MMB 2))
The same procedure as for the preparation of the micro master batch 1 (MMB 1) was conducted except that the master batch resin 1 was changed to the master batch resin 2, to obtain a micro master batch (MMB 2) for an adhesive of comparative example.
(preparation of micro master batch 3 (MMB 3))
A masterbatch 3 (MMB 3) for an adhesive of a comparative example was obtained in the same manner as in the preparation of the masterbatch 1 (MMB 1), except that the masterbatch resin 1 was changed to the masterbatch resin 3.
(preparation of micro master batch 4 (MMB 4))
A pressure-sensitive adhesive micro master batch 4 (MMB 4) was obtained in the same manner as in the preparation of micro master batch 1 (MMB 1), except that the magenta pigment (pigment Red 122) was changed to a blue pigment (pigment blue 15:3).
(preparation of micro master batch 5 (MMB 5))
A pressure-sensitive adhesive micro master batch 5 (MMB 5) was obtained in the same manner as in the preparation of the micro master batch 1 (MMB 1), except that the magenta pigment (pigment red 122) was changed to a yellow pigment (pigment yellow 185).
(preparation of micro master batch 6 (MMB 6))
A pressure-sensitive adhesive micro master batch 6 (MMB 6) was obtained in the same manner as in the preparation of the micro master batch 1 (MMB 1), except that the magenta pigment (pigment red 122) was changed to the black pigment (pigment black 7) and the master batch resin 1 was changed to the master batch resin 4.
(preparation of micro master batch 7 (MMB 7))
A pressure-sensitive adhesive micro master batch 7 (MMB 7) was obtained in the same manner as in the preparation of the micro master batch 1 (MMB 1), except that the master batch resin 1 was changed to the master batch resin 4 (60 parts by mass) and the magenta pigment (pigment red 122) was changed to the black pigment (pigment black 7) (40 parts by mass).
(preparation of micro master batch 8 (MMB 8))
A pressure-sensitive adhesive micro master batch 8 (MMB 8) was obtained in the same manner as in the preparation of the micro master batch 1 (MMB 1), except that the master batch resin 1 was changed to the master batch resin 5 (60 parts by mass) and the magenta pigment (pigment red 122) was changed to the black pigment (pigment black 7) (40 parts by mass).
Example 1 ]
(preparation of colored adhesive composition)
The above MMB1 was added to the photopolymerizable composition so that the pigment concentration became 0.1 mass% and mixed to obtain a colored adhesive composition.
(production of adhesive sheet)
The colored adhesive composition was applied to a release treated surface of a polyester film A (trade name "DIAFOIL MRF", mitsubishi chemical Co., ltd.) having a thickness of 38 μm, which had been release-treated with a silicone on one surface, to form a coating layer having a thickness of 50 μm, and a release treated surface of a polyester film B (trade name "DIAFOIL MRF", mitsubishi chemical Co., ltd.) having a thickness of 38 μm, which had been release-treated with a silicone on one surface, was bonded to the coating layer, and then the intensity of the irradiated surface immediately below the lamp was set to 200mW/cm 2 The UV-LED lamp with the lamp height adjusted is used for irradiating ultraviolet rays from the surface of the polyester film B side. Polymerization was carried out until 6000mJ/cm was irradiated with a light meter 2 Thus, an adhesive layer (colored adhesive) was formed, and an adhesive sheet having a thickness of 50 μm was produced.
Example 2 ]
A colored adhesive composition and an adhesive sheet of example 2 were produced in the same manner as in example 1, except that MMB1 was added to the photopolymerizable composition so that the pigment concentration became 0.5 mass% and mixed.
Example 3 ]
A colored adhesive composition and an adhesive sheet of example 3 were produced in the same manner as in example 1, except that MMB1 was added to the photopolymerizable composition so that the pigment concentration became 1 mass% and mixed.
Example 4 ]
The pigment dispersion 1 prepared above was added to the photopolymerizable composition so that the pigment concentration became 0.5 mass% and mixed, to obtain a colored binder composition of example 4.
An adhesive sheet of example 4 was produced in the same manner as in example 1.
Example 5 ]
To a polymer solution containing an acrylic polymer of the above adhesive composition 1, 0.3 parts by mass (solid content equivalent) of an isocyanate crosslinking agent (trade name "TAKENATE D N", manufactured by three-well chemical company), 0.01 parts by mass (solid content equivalent) of dibutyltin dilaurate (trade name "OL-1", 1% by mass ethyl acetate solution (manufactured by tokyo fine chemical company)) as a crosslinking catalyst, and 4 parts by mass of acetylacetone as a crosslinking inhibitor (ligand for the crosslinking catalyst) were added to 100 parts by mass of the acrylic polymer, and MMB1 solution diluted with ethyl acetate to a pigment concentration of 13.7% by mass was added and mixed so that the pigment concentration became 0.5% by mass, to obtain a colored adhesive composition of example 5.
(production of adhesive sheet)
The colored adhesive composition was applied to a release-treated surface of a polyester film A (trade name "DIAFOIL MRF", manufactured by Mitsubishi chemical corporation) having a thickness of 38 μm, which was release-treated with a silicone on one surface, to form a coating film. Subsequently, the coating film was dried at 130℃for 3 minutes to form an adhesive layer having a thickness of 20. Mu.m. A release treated surface of a 38 μm thick polyester film B (trade name "DIAFOIL MRF", manufactured by Mitsubishi chemical corporation) having one surface subjected to silicone release treatment was bonded to the pressure-sensitive adhesive layer. Thereafter, the adhesive layer was cured at 60℃for 1 day to crosslink the adhesive layer.
Example 6 ]
A colored adhesive composition and an adhesive sheet of example 6 were produced in the same manner as in example 5, except that MMB4 solution diluted with ethyl acetate to a pigment concentration of 13.4 mass% was added to the polymer solution containing the acrylic polymer of the adhesive composition 1 so that the pigment concentration became 0.5 mass% and mixed.
Example 7 ]
A colored adhesive composition and an adhesive sheet of example 7 were produced in the same manner as in example 5 except that MMB5 solution diluted with ethyl acetate to a pigment concentration of 12.1 mass% was added to and mixed with the polymer solution containing the acrylic polymer of the adhesive composition 1 so that the pigment concentration became 0.5 mass%.
Example 8 ]
A colored adhesive composition and an adhesive sheet of example 8 were produced in the same manner as in example 5, except that MMB6 solution diluted with ethyl acetate to a pigment concentration of 2.5 mass% was added to and mixed with the polymer solution containing the acrylic polymer of the adhesive composition 2 so that the pigment concentration became 1 mass%.
Example 9 ]
A colored adhesive composition and an adhesive sheet of example 9 were produced in the same manner as in example 5, except that MMB7 solution diluted with ethyl acetate to a pigment concentration of 2.5 mass% was added to and mixed with the polymer solution containing the acrylic polymer of the adhesive composition 2 so that the pigment concentration became 1 mass%.
Example 10 ]
A colored adhesive composition and an adhesive sheet of example 10 were produced in the same manner as in example 5, except that MMB8 solution diluted with ethyl acetate to a pigment concentration of 2.5 mass% was added to and mixed with the polymer solution containing the acrylic polymer of the adhesive composition 2 so that the pigment concentration became 1 mass%.
Comparative example 1 ]
The pigment dispersion 2 prepared above was added and mixed to the photopolymerizable composition so that the pigment concentration became 0.5 mass%, to obtain a colored adhesive composition of comparative example 1.
In the same manner as in example 1, an adhesive sheet of comparative example 1 was produced.
Comparative example 2 ]
A colored adhesive composition and an adhesive sheet of comparative example 2 were produced in the same manner as in example 1, except that MMB2 was added to the photopolymerizable composition so that the pigment concentration became 0.5 mass% and mixed.
Comparative example 3 ]
A colored adhesive composition and an adhesive sheet of comparative example 3 were produced in the same manner as in example 1, except that MMB3 was added to the photopolymerizable composition so that the pigment concentration became 0.5 mass% and mixed.
Comparative example 4 ]
The pigment dispersion 3 prepared above was added to the photopolymerizable composition so that the pigment concentration became 0.5 mass% and mixed, to obtain a colored binder composition of comparative example 4.
In the same manner as in example 1, an adhesive sheet of comparative example 4 was produced.
Comparative example 5 ]
The pigment dispersion 4 prepared above was added to the photopolymerizable composition so that the pigment concentration became 0.5 mass% and mixed, to obtain a colored binder composition of comparative example 5.
In the same manner as in example 1, an adhesive sheet of comparative example 5 was produced.
Comparative example 6 ]
A colored adhesive composition and an adhesive sheet of comparative example 6 were produced in the same manner as in example 5, except that the pigment dispersion 5 was added to and mixed with the polymer solution containing the acrylic polymer of the adhesive composition 2 so that the pigment concentration became 1 mass%.
Examples and comparative examples are shown in tables 2 and 3 below.
TABLE 2
TABLE 3
As shown in table 2, the adhesive sheets of examples 1 to 10 showed good appearance without in-plane color unevenness, but comparative examples 1 to 3 and 5 had in-plane color unevenness and poor appearance. The pressure-sensitive adhesive sheets of examples 1 to 10 have a narrow standard deviation of transmittance at a wavelength at which the transmittance becomes the lowest at 400 to 800nm, and have a small color unevenness in the plane of 0.37 to 1.10. As shown in table 3, the standard deviations of comparative examples 1 to 5 were 1.20 to 2.41, which are wider than examples, indicating that the color unevenness in the surface was large.
As shown in tables 2 and 3, the adhesive sheets of examples 1 to 10 showed high adhesion reliability without any decrease in adhesion with time even in a high-temperature and high-humidity environment, but the adhesive sheets of comparative examples 4 and 6 showed decrease in adhesion with time even in a high-temperature and high-humidity environment.
Industrial applicability
According to the present invention, an adhesive layer and an adhesive sheet exhibiting excellent appearance and high adhesion reliability, a colored adhesive composition capable of forming the adhesive layer and the adhesive sheet, a pigment dispersion master batch for an adhesive having excellent dispersibility, and a resin for the pigment dispersion master batch for an adhesive can be provided.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.
The present application is based on Japanese patent application No. 2020, 9 and 30 (Japanese patent application No. 2020-165632), the contents of which are incorporated herein by reference.
Description of the reference numerals
1. 2, 3 pressure-sensitive adhesive sheet
11. 21, 31a, 31b adhesive layers
22. 32 substrate
Claims (5)
1. A resin for pigment-dispersion master batch for adhesives, which contains a resin (A),
The glass transition temperature of the resin (A) is-80-40 ℃,
the acid value of the resin (A) is 1 to 50 (KOHmg/g).
2. A pigment-dispersion master batch for a binder, comprising the resin for a pigment-dispersion master batch for a binder according to claim 1 and a pigment,
the content of the resin (A) is 45 to 90 mass% relative to the total mass of the pigment and the resin (A).
3. A colored adhesive composition comprising the pigment-dispersion masterbatch for adhesive of claim 2 and a base polymer.
4. A colored adhesive composition according to claim 3 wherein the base polymer is an acrylic polymer.
5. An adhesive sheet comprising an adhesive layer formed from the colored adhesive composition according to claim 3 or 4.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2020165632 | 2020-09-30 | ||
| JP2020-165632 | 2020-09-30 | ||
| PCT/JP2021/035468 WO2022071252A1 (en) | 2020-09-30 | 2021-09-27 | Resin for pigment-dispersion masterbatch for pressure-sensitive adhesive, pigment-dispersion masterbatch for pressure-sensitive adhesive, colored pressure-sensitive adhesive composition, and pressure-sensitive adhesive sheet |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116323765A true CN116323765A (en) | 2023-06-23 |
Family
ID=80950366
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202180066952.1A Pending CN116323765A (en) | 2020-09-30 | 2021-09-27 | Resin for pigment-dispersion master batch for adhesive, colored adhesive composition, and adhesive sheet |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JPWO2022071252A1 (en) |
| KR (1) | KR20230079062A (en) |
| CN (1) | CN116323765A (en) |
| TW (1) | TW202225340A (en) |
| WO (1) | WO2022071252A1 (en) |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6044355B2 (en) | 1980-07-11 | 1985-10-03 | モダン・プラスチツク工業株式会社 | Colored adhesive sheet with excellent weather resistance |
| JPH06346040A (en) * | 1993-06-08 | 1994-12-20 | Dainippon Ink & Chem Inc | Colored pressure-sensitive adhesive layer and pressure-sensitive adhesive tape or sheet using the same |
| JPH08281888A (en) * | 1995-04-17 | 1996-10-29 | Nippon Petrochem Co Ltd | Uniaxially oriented material, laminate, nonwoven fabric and fabric and reinforced laminate using them |
| JP2000265133A (en) * | 1999-03-11 | 2000-09-26 | Tomoegawa Paper Co Ltd | Application film for electronic display |
| JP4250731B2 (en) * | 2002-03-28 | 2009-04-08 | リンテック株式会社 | Method for producing decorative adhesive sheet and white toner |
| JP5983198B2 (en) * | 2011-09-09 | 2016-08-31 | 東洋インキＳｃホールディングス株式会社 | Optical pressure-sensitive adhesive, optical pressure-sensitive adhesive sheet, and laminate |
| JP6675825B2 (en) | 2014-11-20 | 2020-04-08 | リンテック株式会社 | Colored adhesive sheet |
| CN106032458A (en) * | 2015-03-13 | 2016-10-19 | 德莎欧洲公司 | Pressure-sensitive adhesive composition and infrared transparent black adhesive tape, preparation method thereof and application thereof |
-
2021
- 2021-09-27 JP JP2022553971A patent/JPWO2022071252A1/ja active Pending
- 2021-09-27 WO PCT/JP2021/035468 patent/WO2022071252A1/en active Application Filing
- 2021-09-27 CN CN202180066952.1A patent/CN116323765A/en active Pending
- 2021-09-27 KR KR1020237010378A patent/KR20230079062A/en unknown
- 2021-09-29 TW TW110136311A patent/TW202225340A/en unknown
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| TW202225340A (en) | 2022-07-01 |
| KR20230079062A (en) | 2023-06-05 |
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