JP2009134178A - Color filter, and liquid crystal display device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color filter having good color characteristic and high contrasts, which is produced using a dispersion composition of pigment fine particles having fine dispersibility and dispersion stability, and to provide a liquid crystal display device using the same, which exhibits excellent display properties. <P>SOLUTION: The color filter has a pixel containing a graft polymer compound and a pigment dispersion composition containing organic pigment particles formed by mixing a solution prepared by dissolving an organic pigment in a good solvent with a bad solvent of the organic pigment compatible with the good solvent. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a color filter and a liquid crystal display device using the color filter.

  In recent years, color filters tend to be used not only for monitors but also for televisions (TVs) in liquid crystal display (LCD) applications. Along with this trend of expanding applications, advanced color characteristics are required in terms of chromaticity and contrast. In addition, in the image sensor (solid-state imaging device) application, a device having high color characteristics is also demanded. In response to such demands, it is required to disperse the pigment in a finer state (good fine dispersibility) and to disperse in a stable state (good dispersion stability). However, when the pigment particle size is reduced to, for example, nanometer size, the surface area of the pigment particles increases, so the cohesive force between the pigment particles increases, and the above-mentioned fine dispersibility and dispersion stability are achieved at a high level. It is often difficult to achieve both.

  By the way, as a pigment dispersant, it has been proposed to use two types of a basic pigment dispersant and an acidic pigment dispersant in combination (see Patent Document 1). However, here, since the basic pigment dispersant and the acidic pigment dispersant are used in combination, the pigment may be cross-linked. Further, the fine dispersibility and dispersion stability of the pigment are not necessarily sufficient. Also disclosed is a polymer pigment dispersant in which a sulfonic acid group or a monosulfate group is introduced only at one end of a polymer portion (see Patent Document 2). However, this is not an industrially advantageous and efficient production method in terms of introducing terminal groups by polymer synthesis reaction. Moreover, it is not known whether fine dispersibility and dispersion stability are sufficiently improved.

Furthermore, a method is disclosed in which organic pigment particles are precipitated in a liquid mixed in a liquid phase, and a predetermined polymer compound is contained therein (see Patent Documents 3 to 6).
JP 2002-296770 A JP 2002-273191 A International Publication WO2006 / 121016 Pamphlet JP 2004-043776 A JP 2007-023169 A JP 2007-119586 A

  The present invention relates to a color filter having good color characteristics and high contrast produced using a dispersion composition of fine pigment particles having fine dispersion and dispersion stability, and a liquid crystal display device having excellent display characteristics using the color filter. For the purpose of provision.

The above object has been achieved by the following means.
(1) A pigment dispersion composition comprising organic pigment particles formed by mixing a solution obtained by dissolving an organic pigment in a good solvent and a poor solvent for the organic pigment compatible with the good solvent, and a graft polymer compound A color filter having a pixel containing.
(2) The color filter according to (1), wherein the pigment dispersion composition contains substantially no solvent in the mixed liquid in which the organic pigment particles are formed, and contains a different final solvent.
(3) A step of substituting the solvent component in the mixed solution with the final solvent by reducing or removing the solvent component in the mixed solution and adding a different type of substitution solvent from the solvent component in the mixed solution The color filter according to (1) or (2), wherein the process is repeated at least once.
(4) The pigment dispersion composition is obtained by coexisting the graft polymer compound at the time of forming the organic pigment particles, (1) to (3), Color filter.
(5) In any one of (1) to (4), the pigment dispersion composition is obtained by containing the graft polymer compound after the formation of the organic pigment particles. The color filter described.
(6) A liquid crystal display device comprising the color filter according to any one of (1) to (5).
(7) The liquid crystal display device according to (6), wherein the liquid crystal display device is a VA system.

  The color filter of the present invention is produced using a dispersion composition of fine pigment particles having fine dispersibility and dispersion stability, and exhibits good color characteristics such as high color rendering power and suppression of color unevenness, and high contrast, A liquid crystal display device using the same suppresses and prevents image sticking and exhibits excellent display characteristics.

Hereinafter, the present invention will be described in detail.
When the branch of the graft polymer compound used in the color filter of the present invention is referred to as a polymer compound, examples thereof include polystyrene, polyethylene oxide, polypropylene oxide, poly (meth) acrylate ester, polycaprolactone, etc. A graft polymer compound having a structural unit represented by the formula (5) in the branch is preferred.

In the general formula (5), R ⁷⁴ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. Q represents a cyano group, an aryl group having 6 to 30 carbon atoms, or —COOR ⁷⁵ . ^{Here, R 75} represents a hydrogen atom, an alkyl group having 1 to 22 carbon atoms or an aryl group having 6 to 30 carbon atoms.

When R ⁷⁴ is an alkyl group having 1 to 8 carbon atoms, an alkyl group having 1 to 6 carbon atoms is preferable, and a methyl group is more preferable. R ⁷⁴ may have a substituent T ₁ . Examples of the substituent T ₁ include a halogen atom, a carboxyl group, an alkoxycarbonyl group, and an alkoxy group. When the substituent T ₁ is an alkyl group, specific examples include a methyl group, an ethyl group, a hexyl group, an octyl group, a trifluoromethyl group, a carboxymethyl group, and a methoxycarbonylmethyl group. R ⁷⁴ is preferably a hydrogen atom or a methyl group.

Q is preferably an aryl group having 6 to 20 carbon atoms, and more preferably an aryl group having 6 to 12 carbon atoms. It may have a substituent group T ₂ when the group represented by Q is an aryl group. Examples of the substituent T ₂ include a halogen atom, an alkyl group, an alkoxy group, and an alkoxycarbonyl group. When Q is an aryl group, specific examples thereof include phenyl group, naphthyl group, tolyl group, xylyl group, propylphenyl group, butylphenyl group, octylphenyl group, dodecylphenyl group, methoxyphenyl group, ethoxyphenyl. Group, butoxyphenyl group, decyloxyphenyl group, chlorophenyl group, dichlorophenyl group, bromophenyl group, methoxycarbonylphenyl group, ethoxycarbonylphenyl group, butoxycarbonylphenyl group and the like. When Q is an aryl group, an unsubstituted aryl group or an aryl group substituted with a halogen atom, an alkyl group, or an alkoxy group is preferable. Among these, an unsubstituted aryl group or an aryl group substituted with an alkyl group is particularly preferable.

When R ⁷⁵ is an alkyl group having 1 to 22 carbon atoms, preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms. When Q is —COOR ⁷⁵ and R ⁷⁵ is an alkyl group, it may have a substituent T ₃ . Examples of the substituent T ₃ include a halogen atom, an alkenyl group, an aryl group, a hydroxyl group, an alkoxy group, an alkoxycarbonyl group, an amino group, an acylamino group, and a carbamoyl group. When R ⁷⁵ is an alkyl group, specific examples thereof include methyl group, ethyl group, propyl group, butyl group, heptyl group, hexyl group, octyl group, decyl group, dodecyl group, tridecyl group, tetradecyl group, Hexadecyl group, octadecyl group, 2-chloroethyl group, 2-bromoethyl group, 2-methoxycarbonylethyl group, 2-methoxyethyl group, 2-bromopropyl group, 2-butenyl group, 2-pentenyl group, 3-methyl-2 -Pentenyl group, 2-hexenyl group, 4-methyl-2-hexenyl group, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group, 2-naphthylethyl group, chlorobenzyl group, bromobenzyl group, methylbenzyl Group, ethylbenzyl group, methoxybenzyl group, dimethylbenzyl group, dimethoxybenzyl group Cyclohexyl group, 2-cyclohexylethyl group, 2-cyclopentylethyl group, bicyclo [3.2.1] oct-2-yl group, 1-adamantyl group, dimethylaminopropyl group, acetylaminoethyl group, N, N- Examples include dibutylaminocarbamoylmethyl group. Of these alkyl groups, an unsubstituted alkyl group or an alkyl group substituted with a halogen atom, an aryl group, or a hydroxyl group is preferable. Among these, an unsubstituted alkyl group is particularly preferable.

When R ⁷⁵ is an aryl group having 6 to 30 carbon atoms, preferably an aryl group having 6 to 20 carbon atoms, particularly preferably an aryl group having 6 to 12 carbon atoms. R ⁷⁵ may have a substituent T ₄ when it is an aryl group. Examples of the substituent T ₄ include a halogen atom, an alkyl group, an alkenyl group, an alkoxy group, an alkoxycarbonyl group, and an acylamino group. Specific examples when R ⁷⁵ is an aryl group include a phenyl group, a naphthyl group, a tolyl group, a xylyl group, a propylphenyl group, a butylphenyl group, an octylphenyl group, a dodecylphenyl group, a methoxyphenyl group, and an ethoxyphenyl group. Group, butoxyphenyl group, decyloxyphenyl group, chlorophenyl group, dichlorophenyl group, bromophenyl group, methoxycarbonylphenyl group, ethoxycarbonylphenyl group, butoxycarbonylphenyl group, acetamidophenyl group, propioamidophenyl group, dodeciloylamide A phenyl group, and the like. Among such aryl groups, an unsubstituted aryl group or an aryl group substituted with a halogen atom, an alkyl group, or an alkoxy group is preferable. Among them, an aryl group substituted with an alkyl group is particularly preferable.

R ⁷⁵ is preferably a hydrogen atom or an alkyl group having 1 to 22 carbon atoms, and particularly preferably a hydrogen atom or an alkyl group having 1 to 12 carbon atoms.

  A specific example of the branch part of the graft polymer having the structural unit represented by the general formula (5) in the branch part is, for example, polymethyl (meth) acrylate, poly-n. -Butyl (meth) acrylate, poly-i-butyl (meth) acrylate, poly (methyl (meth) acrylate-co-benzyl (meth) acrylate), poly (methyl (meth) acrylate-co-styrene), poly (methyl (Meth) acrylate-co- (meth) acrylic acid), poly (methyl (meth) acrylate-co-acrylonitrile), and the like.

  The graft polymer used in the present invention is not particularly limited, but is preferably a polymer in which a site having a side chain is bonded to the main chain by a covalent bond directly or via a spacer site, and is not limited thereto. For example, a copolymer composed of a polymerizable oligomer component having an ethylenically unsaturated double bond at the terminal as a copolymer component, or a component that becomes a graft site on a (co) polymer having a side chain. And those having a graft site formed by polymerization reaction starting from a polymer having a side chain. The graft polymer in the present invention is synthesized by referring to a known polymer reaction or a copolymerization reaction with a polymerizable monomer and a polymerizable oligomer having an ethylenically unsaturated double bond at the terminal. Can be used.

  As a method for synthesizing a graft-type polymer compound having at least a structural unit represented by the general formula (5) in a branch part, specifically, a polymerizable compound forming the structural unit represented by the general formula (5) is used. Examples thereof include a method of copolymerizing a macromonomer and an ethylenically unsaturated monomer copolymerizable with the macromonomer.

  Among the polymerizable macromonomers constituting the structural unit represented by the general formula (5), preferred are those represented by the following general formula (6).

In General Formula (6), ^R76 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. W represents a single bond or a group represented by any of the following (a) to (n).

Here, Z < ₁ >, Z < ₂ > represents a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a cyano group, or a hydroxyl group. Z ₃ represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an aryl group having 6 to 20 carbon atoms. Alternatively, Z _{1 to} Z ₃ may be a linking group in which these are combined. A, together with w, represents a group forming Q of the structural unit represented by the general formula (5). Specific examples of the macromonomer represented by the general formula (6) include compounds represented by the following formulas (6-1) to (6-8).

  A has the same meaning as A in the general formula (6). Me represents a methyl group. As such a macromonomer available as a commercial product, one-terminal methacryloylated polymethyl methacrylate oligomer (Mn = 6000, trade name: AA-6, manufactured by Toagosei Chemical Co., Ltd.), one-terminal methacryloylated poly- n-butyl acrylate oligomer (Mn = 6000, trade name: AB-6, manufactured by Toa Gosei Chemical Co., Ltd.), single-end methacryloylated polystyrene oligomer (Mn = 6000, trade name: AS-6, Toa Gosei Chemical Industries) (Manufactured by Co., Ltd.).

  The molecular weight of the macromonomer is preferably a polystyrene-equivalent number average molecular weight (Mn) of 1000 to 20000, and more preferably 2000 to 15000. When the number average molecular weight is within the above range, the steric repulsion effect as a pigment dispersant can be more effectively obtained. In the present invention, the term “molecular weight” means a number average molecular weight, and unless otherwise specified, is a molecular weight in terms of polystyrene measured by gel permeation chromatography (carrier: tetrahydrofuran).

  As the ethylenically unsaturated monomer copolymerizable with the macromonomer described above, “a monomer constituting a block adsorbed to the pigment” may be used in order to improve the dispersibility and dispersion stability of the pigment. preferable. Further, as other copolymerization component, “a monomer constituting a block that is not adsorbed to the pigment” may be copolymerized.

The “monomer constituting the block adsorbed to the pigment” can be appropriately selected according to the kind of the pigment to be dispersed, and these may be used alone or in combination of two or more.
For example, the monomer which has a functional group which can adsorb | suck to a pigment is mentioned. Specifically, a monomer having an organic dye residue or a heterocyclic structure, a monomer having an acidic group, a monomer having a basic nitrogen atom, a urea group, a urethane group, a group having a coordinating oxygen atom, a carbon number of 4 Examples thereof include monomers having the above hydrocarbon groups, alkoxysilyl groups, epoxy groups, isocyanate groups, or hydroxyl groups, or monomers having ionic functional groups. Among them, organic dye residues or heterocyclic structures Monomers having an acidic group, or monomers having a basic nitrogen atom are preferred, and monomers having an acidic group or monomers having a basic nitrogen atom are particularly preferred.

  The “monomer constituting the block that is not adsorbed to the pigment” is not particularly limited. For example, (meth) acrylic acid esters, crotonic acid esters, vinyl esters, maleic acid diesters, fumaric acid diesters, Itaconic acid diesters, (meth) acrylamides, styrenes, vinyl ethers, vinyl ketones, olefins, maleimides, (meth) acrylonitrile and the like can be mentioned. These monomers may be used independently and may use 2 or more types together. When applied to a photocurable composition that requires an alkali development treatment, a monomer that constitutes a block that is not adsorbed by the pigment and a vinyl monomer having an acidic group may be used in combination.

  Examples of (meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and n-butyl (meth) acrylate. , Isobutyl (meth) acrylate, t-butyl (meth) acrylate, amyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, t-butylcyclohexyl (meth) acrylate, (Meth) acrylic acid 2-ethylhexyl, (meth) acrylic acid t-octyl, (meth) acrylic acid dodecyl, (meth) acrylic acid octadecyl, (meth) acrylic acid acetoxyethyl, (meth) acrylic acid phenyl, (meth) 4-hydroxybutyl acrylate, 2-methoxyethyl (meth) acrylate, (meth) a 2-ethoxyethyl laurate, 2- (2-methoxyethoxy) ethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, vinyl (meth) acrylate, 2-phenylvinyl (meth) acrylate, (meth ) 1-propenyl acrylate, allyl (meth) acrylate, 2-allyloxyethyl (meth) acrylate, propargyl (meth) acrylate, benzyl (meth) acrylate, diethylene glycol monomethyl ether (meth) acrylate, (meth ) Diethylene glycol monoethyl ether acrylate, (meth) acrylic acid triethylene glycol monomethyl ether, (meth) acrylic acid triethylene glycol monoethyl ether, (meth) acrylic acid polyethylene glycol monomethyl ether, (meth) acrylic acid polyethylene Glycol monoethyl ether, β-phenoxyethoxyethyl (meth) acrylate, nonylphenoxy polyethylene glycol (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, (meth) acryl Trifluoroethyl acid, octafluoropentyl (meth) acrylate, perfluorooctyl ethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, tribromophenyl (meth) acrylate, tribromo (meth) acrylate Examples thereof include phenyloxyethyl and (meth) acrylic acid γ-butyrolactone.

Examples of crotonic acid esters include butyl crotonate and hexyl crotonate.
Examples of vinyl esters include vinyl acetate, vinyl chloroacetate, vinyl propionate, vinyl butyrate, vinyl methoxyacetate, vinyl benzoate, and the like.
Examples of maleic acid diesters include dimethyl maleate, diethyl maleate, and dibutyl maleate.
Examples of the fumaric acid diesters include dimethyl fumarate, diethyl fumarate, and dibutyl fumarate.
Examples of itaconic acid diesters include dimethyl itaconate, diethyl itaconate, and dibutyl itaconate.

  (Meth) acrylamides include (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-propyl (meth) acrylamide, N-isopropyl (meth) acrylamide, and Nn-butyl. Acrylic (meth) amide, Nt-butyl (meth) acrylamide, N-cyclohexyl (meth) acrylamide, N- (2-methoxyethyl) (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N -Diethyl (meth) acrylamide, N-phenyl (meth) acrylamide, N-nitrophenyl acrylamide, N-ethyl-N-phenyl acrylamide, N-benzyl (meth) acrylamide, (meth) acryloylmorpholine, diacetone acrylamide, N- Methylo Acrylamide, N- hydroxyethyl acrylamide, vinyl (meth) acrylamide, N, N- diallyl (meth) acrylamide, such as N- allyl (meth) acrylamide.

  Examples of styrenes include styrene, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, isopropyl styrene, butyl styrene, hydroxy styrene, methoxy styrene, butoxy styrene, acetoxy styrene, chlorostyrene, dichlorostyrene, bromostyrene, chloromethyl Examples thereof include styrene, hydroxystyrene protected with a group that can be deprotected by an acidic substance (for example, t-Boc and the like), methyl vinylbenzoate, and α-methylstyrene.

  Examples of vinyl ethers include methyl vinyl ether, ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, hexyl vinyl ether, octyl vinyl ether, methoxyethyl vinyl ether, and phenyl vinyl ether.

Examples of vinyl ketones include methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, and phenyl vinyl ketone.
Examples of olefins include ethylene, propylene, isobutylene, butadiene, isoprene and the like.
Examples of maleimides include maleimide, butyl maleimide, cyclohexyl maleimide, and phenyl maleimide.
Examples of (meth) acrylonitrile include methacrylonitrile and acrylonitrile.

  The mass average molecular weight of the graft polymer compound is not particularly limited, but is preferably in the range of 3,000 to 100,000, and more preferably in the range of 5,000 to 50,000. When the mass average molecular weight is 3000 or more, a stabilizing effect can be obtained more effectively, and when the mass average molecular weight is 100,000 or less, it can be more effectively adsorbed to exhibit good dispersibility. . In the present invention, the term “molecular weight” simply means a mass average molecular weight, and unless otherwise specified, is a molecular weight in terms of polystyrene measured by gel permeation chromatography (carrier: tetrahydrofuran).

  Commercially available products of the graft polymer include “Solspers 24000, 28000, 32000, 38500, 39000, 55000” manufactured by Lubrizol, “Disperbyk-111, 161, 171, 174” manufactured by BYK Chemie, etc. Product name).

  In addition, the graft type polymer used in the color filter of the present invention is not particularly limited. However, polyalkyleneimine and a polyester compound described in JP 54-37082 A, JP 61-174939 A, and the like are used. Compounds obtained by reaction, compounds in which the amino group of the side chain of polyallylamine described in JP-A-9-169621 is modified with polyester, polyurethanes added with a polyester polyol described in JP-A-60-166318, etc. No. 171253, Macromonomer Chemistry and Industry, IP Publishing Co., Ltd., 1989, and the like, and polymerizable oligomers (hereinafter referred to as macromonomers) as copolymerization components can be mentioned.

  In the pigment dispersion composition used in the color filter of the present invention, the content of the graft polymer compound is not particularly limited, but is 1 to 80% by mass with respect to the total solid content of the pigment dispersion composition. Preferably, it is 3-50 mass%.

  In the present invention, other polymers and various dispersing agents can be used together with the graft polymer compound. Although it does not restrict | limit in particular in this invention, A pigment derivative type compound and a terminal modified | denatured high molecular compound are mentioned as what is preferably used.

  A pigment derivative type compound (hereinafter also referred to as “pigment derivative type dispersant”) is a pigment derivative type dispersant derived from an organic pigment as a parent substance and produced by chemically modifying the parent structure, or chemical. It is defined as a pigment derivative type dispersant obtained by a pigmentation reaction of a modified pigment precursor. Generally, it is also called a synergist type dispersant.

Although not particularly limited, for example, a functional group such as a pigment derivative having an acidic group, a pigment derivative having a basic group, or a phthalimidomethyl group described in JP-A-2007-9096, JP-A-7-331182, or the like. The introduced pigment derivative is preferably used.
Commercially available products include “EFKA 6745 (trade name, phthalocyanine derivative)”, 6750 (trade name, azo pigment derivative) manufactured by EFKA, and “Solspers 5000 (trade name, phthalocyanine derivative)”, 22000 (trade name, azo) manufactured by Lubrizol. Pigment derivatives) ”and the like.

  The content of the pigment derivative-type compound in the pigment dispersion composition used in the color filter of the present invention is not particularly limited, but is preferably 0.01 to 50% by mass in the total solid content of the composition. More preferably, it is 2-20 mass%.

The method for synthesizing the above-mentioned terminal-modified polymer compound is not particularly limited, and examples thereof include the following method and a combination thereof.
1. 1. A method of synthesizing by polymerization (for example, radical polymerization, anionic polymerization, cationic polymerization, etc.) using a functional group-containing polymerization initiator Method of synthesizing by radical polymerization using a functional group-containing chain transfer agent The functional group introduced here is the adsorption site (that is, organic dye structure, heterocyclic structure, acidic group, group having basic nitrogen atom, urea group) , A urethane group, a group having a coordinating oxygen atom, a hydrocarbon group having 4 or more carbon atoms, an alkoxysilyl group, an epoxy group, an isocyanate group, a hydroxyl group, and an ionic functional group). Moreover, you may be a functional group which can be induced | guided | derived to these adsorption sites.

  Examples of the chain transfer agent capable of introducing a functional group at the polymer terminal include mercapto compounds (for example, thioglycolic acid, thiomalic acid, thiosalicylic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, 3-mercaptobutyric acid, N- ( 2-mercaptopropionyl) glycine, 2-mercaptonicotinic acid, 3- [N- (2-mercaptoethyl) carbamoyl] propionic acid, 3- [N- (2-mercaptoethyl) amino] propionic acid, N- (3- Mercaptopropionyl) alanine, 2-mercaptoethanesulfonic acid, 3-mecaptopropanesulfonic acid, 4-mercaptobutanesulfonic acid, 2-mercaptoethanol, 3-mercapto-1,2-propanediol, 1-mercapto-2-propanol 3-mercapto-2-butano , Mercaptophenol, 2-mercaptoethylamine, 2-mercaptoimidazole, 2-mercapto-3-pyridinol, benzenethiol, toluenethiol, mercaptoacetophenone, naphthalenethiol, naphthalenemethanethiol, etc.) or oxidized products of these mercapto compounds Examples thereof include disulfide compounds and halogen compounds (for example, 2-iodoethanesulfonic acid, 3-iodopropanesulfonic acid, etc.).

  Moreover, as a polymerization initiator which can introduce | transduce a functional group into a polymer terminal, for example, 2,2'-azobis (2-cyanopropanol), 2,2'-azobis (2-cyanopentanol), 4,4'- Azobis (4-cyanovaleric acid), 4,4′-azobis (4-cyanovaleric acid chloride), 2,2′-azobis [2- (5-methyl-2-imidazolin-2-yl) propane], 2 , 2′-azobis [2- (2-imidazolin-2-yl) propane], 2,2′-azobis [2- (3,4,5,6-tetrahydropyrimidin-2-yl) propane], 2, 2'-azobis {2- [1- (2-hydroxyethyl) -2-imidazolin-2-yl] propane}, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide ] Or this Like derivatives of.

As the monomer used for the polymerization, for example, the above-mentioned “monomer constituting a block that is not adsorbed to the pigment” can be used as the radical polymerizable monomer.
Examples of the terminal-modified polymer include polymers having a functional group at the end of the polymer described in JP-A-9-77994, JP-A-2002-273191, and the like.

  The molecular weight of the terminal-modified polymer is preferably a mass average molecular weight of 1,000 to 50,000. When the number average molecular weight is 1000 or more, the steric repulsion effect as a pigment dispersant can be more effectively obtained, and when it is 50000 or less, the steric effect is more effectively suppressed and the adsorption to the pigment is reduced. Time can be shortened.

  Examples of the commercially available terminal-modified polymer include “Solspers 3000, 17000, 27000 (all are trade names)” manufactured by Lubrizol.

  The content of the terminal-modified polymer compound in the pigment dispersion composition used for the color filter of the present invention is not particularly limited, but is preferably 1 to 80% by mass in the total solid content of the composition. More preferably, it is 50 mass%.

  In the pigment dispersion composition, the above-described graft polymer compound is contained, and preferably the pigment derivative-type compound and / or the terminal-modified polymer compound are further used to improve the fine dispersibility and dispersion stability of the pigment. Can be made. Furthermore, the finely-divided state of the pigment particles can be maintained, the coloring power can be improved, and the suitability for use (particularly non-aggregability, non-crystallinity, fluidity) can be improved. Thereby, when the color filter of this invention is comprised, the outstanding color characteristic and high contrast can be obtained.

  The organic pigment used in the color filter of the present invention is not limited in hue, for example, a perylene compound pigment, a perinone compound pigment, a quinacridone compound pigment, a quinacridone quinone compound pigment, an anthraquinone compound pigment, an anthrone compound pigment, Benzimidazolone compound pigment, disazo condensation compound pigment, disazo compound pigment, azo compound pigment, indanthrone compound pigment, phthalocyanine compound pigment, triarylcarbonium compound pigment, dioxazine compound pigment, aminoanthraquinone compound pigment, diketopyrrolopyrrole compound pigment Thioindigo compound pigments, isoindoline compound pigments, isoindolinone compound pigments, pyranthrone compound pigments, isoviolanthrone compound pigments, and mixtures thereof.

  Among them, quinacridone compound pigments, diketopyrrolopyrrole compound pigments, dioxazine compound pigments, phthalocyanine compound pigments, or azo compound pigments are preferable, and diketopyrrolopyrrole compound pigments, phthalocyanine compound pigments, or dioxazine compound pigments are more preferable. . At this time, two or more kinds of organic pigments or solid solutions of organic pigments can be used in combination. Moreover, you may combine with an organic pigment | dye, a polymeric organic material, etc.

  In the color filter of the present invention, an organic pigment solution in which an organic pigment is dissolved in a good solvent (first solvent), a solvent that is compatible with the good solvent and is a poor solvent for the organic pigment (second Build-up pigment particles formed by mixing with a solvent. Here, the combination of the good solvent and the poor solvent needs to have a sufficient difference in the solubility of the organic pigment, and it is necessary to select a preferable one according to the organic pigment, but it enables the precipitation of pigment particles. Any combination is possible.

  The good solvent is not particularly limited as long as it can dissolve the organic pigment to be used and is compatible with or uniformly mixed with the poor solvent. As for the solubility of the organic pigment in a good solvent, the solubility of the organic pigment is preferably 0.2% by mass or more, and more preferably 0.5% by mass or more. Although there is no particular upper limit to the solubility of the organic pigment in the good solvent, it is practical that it is 50% by mass or less in consideration of a commonly used organic pigment. This solubility may be the solubility when dissolved in the presence of an acid or alkali.

  Examples of the good solvent include an aqueous solvent (for example, water or hydrochloric acid, an aqueous sodium hydroxide solution), an alcohol compound solvent, an amide compound solvent, a ketone compound solvent, an ether compound solvent, an aromatic compound solvent, a carbon disulfide solvent, and a fat. Group compound solvents, nitrile compound solvents, sulfoxide compound solvents, halogen compound solvents, ester compound solvents, ionic liquids, mixed solvents thereof, and the like, aqueous solvents, alcohol compound solvents, ketone compound solvents, ether compound solvents, sulfoxide compounds Solvents, ester compound solvents, amide compound solvents, or mixtures thereof are preferred, aqueous solvents, alcohol compound solvents, ester compound solvents, sulfoxide compound solvents or amide compound solvents are preferred, aqueous solvents, sulfoxide compound solvents or amide compounds. More preferably medium, sulfoxide compound solvent or the amide compound solvent is particularly preferred.

  Examples of the sulfoxide compound solvent include dimethyl sulfoxide, diethyl sulfoxide, hexamethylene sulfoxide, sulfolane and the like. Examples of the amide compound solvent include N, N-dimethylformamide, 1-methyl-2-pyrrolidone, 2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 2-pyrrolidinone, ε-caprolactam, formamide, N -Methylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpropanamide, hexamethylphosphoric triamide and the like.

Further, the concentration of the organic pigment solution in which the organic pigment is dissolved in the good solvent is preferably a saturated concentration of the organic pigment with respect to the good solvent in the dissolving condition or a range of about 1/100 of this.
There are no particular limitations on the conditions for preparing the organic pigment solution, and a range from normal pressure to subcritical and supercritical conditions can be selected. The temperature at normal pressure is preferably −10 to 150 ° C., more preferably −5 to 130 ° C., and particularly preferably 0 to 100 ° C.

  There are some common examples of those listed as specific examples of good solvents and those listed as poor solvents, but the same solvents are not combined as good solvents and poor solvents. It is sufficient that the solubility in is sufficiently higher than the solubility in a poor solvent. For example, the solubility difference is preferably 0.2% by mass or more, and more preferably 0.5% by mass or more. Although there is no particular upper limit to the difference in solubility between the good solvent and the poor solvent, it is practical that the difference is 50% by mass or less in consideration of a commonly used organic pigment.

  When the organic pigment is uniformly dissolved in a good solvent, a pigment dissolution accelerator such as acid or alkali may be added and dissolved. In general, in the case of a pigment having an alkaline and dissociable group in the molecule, addition of an alkali is performed. Is preferred. For example, quinacridone, diketopyrrolopyrrole and disazo condensation compound pigments are alkaline and dissolved. Phthalocyanine compound pigments are dissolved in an acidic manner, but some of them are dissolved in an alkaline manner, and the mechanism of dissolving in an alkaline manner is not clear.

  Examples of the alkali include inorganic bases such as lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, and barium hydroxide, or organic bases such as trialkylamine, diazabicycloundecene (DBU), and metal alkoxide. Of these, trialkylamines and metal alkoxides are preferable, and metal alkoxides are more preferable. The amount of alkali added is not particularly limited, but in the case of an inorganic base, it is preferably 1.0 to 30 molar equivalents, more preferably 1.0 to 25 molar equivalents, and 1.0 Particularly preferred is ˜20 molar equivalents. In the case of an organic base, it is preferably 1.0 to 100 molar equivalents, more preferably 5.0 to 100 molar equivalents, and particularly preferably 20 to 100 molar equivalents with respect to the organic pigment.

  Examples of the acid include inorganic acids such as sulfuric acid, hydrochloric acid, and phosphoric acid, or organic acids such as acetic acid, trifluoroacetic acid, oxalic acid, methanesulfonic acid, and trifluoromethanesulfonic acid. Among them, inorganic acids are preferable. More preferably, it is sulfuric acid. The amount of acid to be added is not particularly limited, but it is often used in excess compared to the base. Regardless of the inorganic acid and organic acid, the organic pigment is preferably 3 to 500 molar equivalents, more preferably 10 to 500 molar equivalents, and particularly preferably 30 to 200 molar equivalents. .

  When mixing alkali or acid with an organic solvent and using it as a good solvent for organic pigments, a solvent having high solubility in some alkali or acid such as water or lower alcohol in order to completely dissolve the alkali or acid Can be added to the organic solvent. The amount of water or lower alcohol is preferably 50% by mass or less, more preferably 30% by mass or less, based on the total amount of the organic pigment solution. Specifically, water, methanol, ethanol, n-propanol, isopropanol, butyl alcohol, or the like can be used.

  While dissolution of the organic pigment proceeds in a good solvent, decomposition of the organic pigment molecule may proceed. Although the decomposition of the pigment molecules will be described later, it is preferable to suppress the decomposition of the organic pigment when the organic pigment solution and the poor solvent are brought into contact with each other. In particular, when the organic pigment is dissolved by the action of the pigment dissolution accelerator and at the same time the decomposition of the organic pigment molecule proceeds, the pigment dissolution accelerator is added to the good solvent immediately before contacting the organic pigment solution with the poor solvent. Is preferably added. At this time, for example, an organic pigment is added to a good solvent (for example, dimethyl sulfoxide), prepared as a dispersion in which the organic pigment is not completely dissolved, and a pigment dissolution accelerator composed of the acid or alkali is added. An embodiment in which the pigment solution is mixed with the poor solvent immediately after the pigment solution is preferable.

  The viscosity of the organic pigment solution is preferably 0.5 to 80.0 mPa · s, and more preferably 1.0 to 50.0 mPa · s.

  Although a poor solvent is not specifically limited, It is preferable that the solubility of an organic pigment is 0.02 mass% or less, and it is more preferable that it is 0.01 mass% or less. Although there is no particular lower limit to the solubility of the organic pigment in the poor solvent, 0.000001% by mass or more is practical in consideration of a commonly used organic pigment. This solubility may be the solubility when dissolved in the presence of an acid or alkali. In addition, the compatibility or uniform mixing property of the good solvent and the poor solvent is preferably 30% by mass or more, more preferably 50% by mass or more, with respect to the poor solvent.

  Examples of the poor solvent include an aqueous solvent (for example, water or hydrochloric acid, an aqueous sodium hydroxide solution), an alcohol compound solvent, a ketone compound solvent, an ether compound solvent, an aromatic compound solvent, a carbon disulfide solvent, an aliphatic compound solvent, Examples thereof include nitrile compound solvents, halogen compound solvents, ester compound solvents, ionic liquids, and mixed solvents thereof, and aqueous solvents, alcohol compound solvents, ketone compound solvents, ether compound solvents, ester compound solvents, or mixtures thereof are preferable. An aqueous solvent, an alcohol compound solvent or an ester compound solvent is more preferable.

Examples of the alcohol compound solvent include methanol, ethanol, isopropyl alcohol, n-propyl alcohol, 1-methoxy-2-propanol, and the like. Examples of the ketone compound solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone. Examples of the ether compound solvent include dimethyl ether, diethyl ether, tetrahydrofuran, and the like. Examples of the aromatic compound solvent include benzene and toluene. Examples of the aliphatic compound solvent include hexane. Examples of the nitrile compound solvent include acetonitrile. Examples of the halogen compound solvent include dichloromethane and trichloroethylene. Examples of the ester compound solvent include ethyl acetate, ethyl lactate, 2- (1-methoxy) propyl acetate and the like. The ionic liquids, for example, 1-butyl-3-methylimidazolium and PF ₆ ^-, etc. and salts thereof.

  There are no particular limitations on the conditions of the poor solvent for precipitation of the organic particles, and a range from normal pressure to subcritical and supercritical conditions can be selected. The temperature at normal pressure is preferably −30 to 100 ° C., more preferably −10 to 60 ° C., and particularly preferably 0 to 30 ° C.

  When mixing the organic pigment solution and the poor solvent, either of them may be added and mixed, but it is preferable to jet the organic pigment solution into the poor solvent and mix, and the poor solvent is stirred at that time. It is preferable that the The stirring speed is preferably 100 to 10,000 rpm, more preferably 150 to 8000 rpm, and particularly preferably 200 to 6000 rpm. A pump or the like may be used for the addition, or it may not be used. Moreover, although addition in a liquid or addition outside a liquid may be sufficient, addition in a liquid is more preferable. Further, it is preferable to continuously supply the liquid into the liquid through a supply pipe. The inner diameter of the supply pipe is preferably 0.1 to 200 mm, more preferably 0.2 to 100 mm. As a speed | rate supplied into a liquid from a supply pipe | tube, 1-1000 ml / min is preferable and 5-5000 ml / min is more preferable.

By adjusting the Reynolds number when mixing the organic pigment solution and the poor solvent, the particle size of the organic nanoparticles to be formed can be controlled. Here, the Reynolds number is a dimensionless number representing the state of fluid flow and is represented by the following equation.
Re = ρUL / μ Equation (1)
In Equation (1), Re represents the Reynolds number, ρ represents the density [kg / m ³ ] of the organic pigment solution, and U represents the relative speed [m / s] when the organic pigment solution and the second solvent meet. L represents the equivalent diameter [m] of the flow path or supply port where the organic pigment solution and the second solvent meet, and μ represents the viscosity coefficient [Pa · s] of the organic pigment solution.

The equivalent diameter L refers to the diameter of the equivalent circular pipe when assuming an opening diameter of a pipe having an arbitrary cross-sectional shape or a circular pipe equivalent to the flow path. The equivalent diameter L is expressed by the following equation (2), where A is the cross-sectional area of the pipe, p is the wetted length (circumferential length) of the pipe, or p is the outer periphery of the flow path.
L = 4 A / p Formula (2)
It is preferable to form particles by injecting an organic pigment solution into a poor solvent through a pipe. When a circular pipe is used for the pipe, the equivalent diameter matches the diameter of the circular pipe. For example, the equivalent diameter can be adjusted by changing the opening diameter of the liquid supply port. Although the value of the equivalent diameter L is not specifically limited, For example, it is synonymous with the preferable internal diameter of the supply port mentioned above.

  The relative speed U when the organic pigment solution and the poor solvent meet is defined by the relative speed in the direction perpendicular to the surface of the portion where both meet. That is, for example, when the organic pigment solution is injected and mixed in a stationary poor solvent, the injection speed from the supply port becomes equal to the relative speed U. Although the value of the relative speed U is not specifically limited, For example, it is preferable to set it as 0.5-100 m / s, and it is more preferable to set it as 1.0-50 m / s.

The density ρ of the organic pigment solution is a value determined by the type of material selected, but is, for example, 0.8 to 2.0 kg / m ³ in the range of the material preferably used in the production method of the present invention. That is practical. Also, the viscosity coefficient μ of the organic pigment solution is a value determined by the material used, the environmental temperature, and the like, but its preferred range is synonymous with the preferred viscosity of the organic pigment solution described above.

  The smaller the Reynolds number (Re) value, the easier it is to form a laminar flow, and the larger the value, the easier it is to form a turbulent flow. For example, the particle size of the organic nanoparticles can be controlled by adjusting the Reynolds number to 60 or more, preferably 100 or more, and more preferably 150 or more. There is no particular upper limit to the number of lay nozzles, but it is preferable because, for example, good organic nanoparticles can be controlled and obtained by adjusting and controlling in the range of 100,000 or less. Or it is good also as conditions which raised Reynolds number so that the average particle diameter of the nanoparticle obtained may be 60 nm or less. At this time, within the above range, it is possible to control and obtain organic nanoparticles having a smaller particle diameter by increasing the Reynolds number.

The mixing ratio of the organic pigment solution and the poor solvent is preferably 1/50 to 2/3 by volume, more preferably 1/40 to 1/2, and particularly preferably 1/20 to 3/8.
When the organic fine particles are deposited, the concentration of nanoparticles in the liquid is not particularly limited, but the organic particles are preferably in the range of 10 to 40,000 mg, more preferably in the range of 20 to 30000 mg, especially with respect to 1000 ml of the solvent. Preferably it is the range of 50-25000 mg.
Moreover, the preparation scale at the time of producing | generating a pigment nanoparticle is although it does not specifically limit, It is preferable that the mixing amount of a poor solvent is a 10-2000L preparation scale, and it is more preferable that it is a 50-1000L preparation scale.

Regarding the particle size of organic particles, there is a method of expressing the average size of the population by quantifying by a measurement method, but as a common use, the mode diameter indicating the maximum value of the distribution, the median value of the integral distribution curve Median diameter, various average diameters (number average, length average, area average, mass average, volume average, etc.), etc. In the present invention, unless otherwise specified, the average particle diameter is the number average. The diameter. The average particle diameter of the pigment fine particles (primary particles) is a nanometer size, the average particle diameter is preferably 1 nm to 1 μm, more preferably 1 to 200 nm, still more preferably 2 to 100 nm, A thickness of 5 to 80 nm is particularly preferable. The particles formed by the production method of the present invention may be crystalline particles, amorphous particles, or a mixture thereof.
In the present invention, the ratio (Mv / Mn) of the volume average particle diameter (Mv) and the number average particle diameter (Mn) is used as an index representing the monodispersity of the particles unless otherwise specified. The monodispersity of the pigment fine particles (primary particles), that is, Mv / Mn, is preferably 1.0 to 2.0, more preferably 1.0 to 1.8, and 1.0 to 1. 5 is particularly preferred.
Examples of the method for measuring the particle size of the organic particles include microscopy, mass method, light scattering method, light blocking method, electrical resistance method, acoustic method, and dynamic light scattering method. Particularly preferred. Examples of the microscope used for the microscopy include a scanning electron microscope and a transmission electron microscope. Examples of the particle measuring apparatus by the dynamic light scattering method include Nanotrack UPA-EX150 manufactured by Nikkiso Co., Ltd. and Dynamic Light Scattering Photometer DLS-7000 series manufactured by Otsuka Electronics Co., Ltd.

  In the present invention, in preparing a dispersion by depositing pigment fine particles, it is preferable to contain a dispersant in at least one of the pigment solution and the poor solvent, and it is preferable to contain a dispersant in at least the pigment solution. In addition, when the pigment particles are deposited, the graft polymer compound may coexist.

  It is also preferable to use pigment particles that have been surface-treated with a dispersant in advance, and the pigment particles may be subjected to a surface treatment that can promote adsorption of the dispersant. The dispersant (1) has a function of quickly adsorbing on the surface of the deposited pigment to form fine nanoparticles and (2) preventing these particles from aggregating again. As the dispersant, for example, anionic, cationic, amphoteric, nonionic or pigment derivative polymer dispersants can be used. Moreover, you may use the above-mentioned graft type polymer compound as this dispersing agent.

  The polymer dispersant preferably has a mass average molecular weight of 1,000 to 500,000, more preferably 10,000 to 500,000, and preferably 10,000 to 100,000. Particularly preferred. Specifically, polyvinyl pyrrolidone, polyvinyl alcohol, polyvinyl methyl ether, polyethylene glycol, polypropylene glycol, polyacrylamide, vinyl alcohol-vinyl acetate copolymer, polyvinyl alcohol-partial formalized product, polyvinyl alcohol-partial butyralized product, vinylpyrrolidone- Vinyl acetate copolymer, polyethylene oxide / propylene oxide block copolymer, polyacrylate, polyvinyl sulfate, poly (4-vinylpyridine) salt, polyamide, polyallylamine salt, condensed naphthalenesulfonate, cellulose derivative, starch Derivatives and the like. In addition, natural polymers such as alginate, gelatin, albumin, casein, gum arabic, tonganto gum and lignin sulfonate can also be used. Of these, polyvinylpyrrolidone is preferable. These polymer compounds can be used singly or in combination of two or more, or a low molecular weight dispersant may be used in combination. The dispersant used for dispersing the pigment is described in detail on pages 29 to 46 of “Pigment dispersion stabilization and surface treatment technology / evaluation” (Chemical Information Association, issued in December 2001).

  Examples of anionic dispersants (anionic surfactants) include N-acyl-N-alkyl taurine salts, fatty acid salts, alkyl sulfate esters, alkyl benzene sulfonates, alkyl naphthalene sulfonates, dialkyl sulfosuccinates, alkyl phosphorus Examples include acid ester salts, naphthalene sulfonic acid formalin condensate, polyoxyethylene alkyl sulfate ester salts, and the like. Of these, N-acyl-N-alkyltaurine salts are preferred. As the N-acyl-N-alkyltaurine salt, those described in JP-A-3-273067 are preferable. These anionic dispersants can be used alone or in combination of two or more.

  Cationic dispersants (cationic surfactants) include quaternary ammonium salts, alkoxylated polyamines, aliphatic amine polyglycol ethers, aliphatic amines, diamines and polyamines derived from aliphatic amines and fatty alcohols, fatty acids And imidazolines derived from these and salts of these cationic substances. These cationic dispersants can be used alone or in combination of two or more.

The amphoteric dispersant is a dispersant having both an anion group part in the molecule of the anionic dispersant and a cationic group part in the molecule of the cationic dispersant.
Nonionic dispersants (nonionic surfactants) include polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkylamine, Examples thereof include glycerin fatty acid esters. Of these, polyoxyethylene alkylaryl ether is preferable. These nonionic dispersants can be used alone or in combination of two or more.

  Examples of the pigment derivative type dispersant include the pigment derivative type compounds described above.

  It is also preferable to use a pigment dispersant containing an amino group as the dispersant. Here, the amino group includes a primary amino group, a secondary amino group, and a tertiary amino group, and the number of amino groups may be one or more. A pigment derivative compound in which a substituent having an amino group is introduced into the pigment skeleton, or a polymer compound having a monomer having an amino group as a polymerization component may be used. Examples of these include, for example, Japanese Patent Application Laid-Open No. 2000-239554, 2003-96329, 2001-31885, Japanese Patent Application Laid-Open No. 10-339949, Japanese Patent Publication No. 5-72943, and International Publication No. WO2006 / 121017. Examples include compounds described in paragraphs 0018 to 0033 of the pamphlet and Japanese Patent Application No. 2006-129714, but are not limited thereto.

  In order to further improve the uniform dispersibility and storage stability of the pigment nanoparticles, the content of the dispersant is preferably in the range of 0.1 to 1000 parts by weight, more preferably 100 parts by weight of the pigment. Is in the range of 1 to 500 parts by weight, more preferably in the range of 5 to 20 parts by weight. If the amount is less than 0.1 parts by mass, the dispersion stability of the pigment nanoparticles may not be improved. Moreover, a dispersing agent may be used independently or may be used in combination of multiple things.

  In the present invention, after the organic pigment fine particles are precipitated, it is preferable to reduce or remove the solvent content of the dispersion containing the precipitated particles (hereinafter, this operation may be simply referred to as concentration). . Thereby, it can be set as the nanoparticle concentrate and organic pigment fine particle powder suitable for a color filter coating liquid.

In the present invention, a normal apparatus can be used alone or in combination for the concentration of the solvent. For example, as dryers using hot air, shelf dryers, band dryers, stirring dryers, fluidized bed dryers, spray dryers, air dryers, etc., dryers using heat conduction are drum dryers, multiple dryers, etc. A tube dryer, a cylindrical dryer or the like is preferably used. Depending on the solvent composition, a freeze dryer or an infrared dryer can be used.
Among these means, a spray dryer (for example, COC-12 manufactured by Okawara Chemical Co., Ltd.), fluidized bed dryer ( For example, Nara Machinery Co., Ltd. MSD-100) is particularly preferably used. In addition, a plurality of drying means may be used in combination in order to obtain organic pigment fine particle powder with a small amount of residual solvent. For example, a pigment dispersion pre-concentrated with a cylindrical dryer is completely dried with a drum dryer. A process such as obtaining a fine powder can be used.
The drying conditions are not particularly limited as long as the solvent can be evaporated and materials such as pigments and dispersants are not denatured. Of course, when other dispersants are denatured at a lower temperature, it is of course necessary to lower the temperature. However, depending on the type of solvent used, the drying speed may be reduced within the allowable temperature range. Can be combined.

The amount to reduce or remove the solvent content is not particularly limited, but in an embodiment in which the solvent content is reduced, it is preferable to remove 50% by mass or more of the total solvent content, and more preferably 75% by mass or more. In an embodiment in which the solvent content is removed to obtain organic pigment fine particle powder, it is preferable to remove 80% by mass or more, and more preferably 90% by mass or more of the total solvent content.
When the solvent content is reduced by reducing or removing the solvent content, the water content in the remaining dispersion is not particularly limited, but is preferably 0.01 to 3% by mass, preferably 0.01 to 1%. It is more preferable to set it as the mass%. At this time, it is preferable to remove the solvent by, for example, the drying method described above to obtain organic pigment fine particle powder. At this time, the solid content is preferably 50 to 100% by mass, and 70 to 100% by mass. More preferably.
The concentration step may be performed a plurality of times, for example, preferably before and / or after the addition of the third solvent described later.

  In the present invention, it is preferable to add another solvent to the concentrated or powdered product as described above and perform solvent replacement one or more times. At this time, it is preferable to redisperse the organic particles in an aggregated state. The organic particles contained in the organic particle liquid concentrated by the extraction solvent, centrifugation, drying, etc. described above may usually be agglomerated by concentration or powdering. As a result, rapid filter filtration is possible, but in order to obtain a good dispersion state again, it is preferable to obtain flocs aggregated to such an extent that they can be redispersed.

  Furthermore, the pigment dispersion composition used in the color filter of the present invention can be formed by controlling the soft aggregates of organic pigment fine particles contained therein through a predetermined treatment / operation. Here, soft agglomeration means an agglomerated state that is weak enough to be redispersed as necessary as described above, and the soft agglomerates are sometimes called flocs. By doing in this way, for example, the organic pigment fine particles precipitated in the aqueous dispersion composition can be flocated and quickly separated by filtration or the like. Then, the separated floc can be re-dispersed in an organic solvent suitable for the production of a color filter to efficiently produce an organic solvent-based dispersion composition. That is, when the mixed solvent of the good solvent (first solvent) and the poor solvent (second solvent) is an aqueous solvent, this is efficiently replaced with a third solvent composed of an organic solvent, and the dispersion medium (continuous phase) Can be switched.

  In order to re-disperse the particles in the above-mentioned soft aggregation state, a normal dispersion method may be insufficient. The graft type polymer compound acts on the formation and re-dispersion of such soft agglomerates (floc), and can be rapidly re-dispersed even once soft agglomerates, thus realizing a good dispersion state. . Therefore, good fine dispersibility (characteristic that achieves uniform and fine particle size) and dispersion stability (uniform and fine particle size can be maintained for a long time) when deposited in a mixture of good and poor solvents. Characteristics) are maintained after the medium is switched to a final solvent suitable for the color filter and redispersed, and high performance in the color filter can be achieved. In addition, the graft polymer compound can achieve high performance in the color filter and the liquid crystal display device without interfering with the optical characteristics of the color filter.

In the present invention, it is preferable to replace the solvent component as described above after precipitation of the pigment fine particles to contain a substitution solvent (third solvent), and this may be used as the final solvent in the pigment dispersion composition. In the present invention, the “final solvent” refers to a main solvent (preferably a solvent occupying 50% by mass or more of the pigment dispersion composition) in the pigment dispersion composition when solidified into a color filter. In addition, it is preferable that the solvent replaced with the final solvent and removed or reduced (for example, the solvent component of the mixed solution in which the organic pigment fine particles are precipitated) is not substantially contained in the dispersion composition. At this time, being substantially not included means that the content does not substantially affect the predetermined performance (contrast, etc.) of the color filter, or less than that. For example, in the above dispersion composition The amount contained in is preferably 10% by mass or less.
Although the kind of 3rd solvent is not specifically limited, It is preferable that it is an organic solvent, for example, an ester compound solvent, an alcohol compound solvent, an aromatic compound solvent, an aliphatic compound solvent, a ketone compound solvent is preferable, an ester compound solvent, a ketone Compound solvents are particularly preferred.

  Examples of the ester compound solvent include 2- (1-methoxy) propyl acetate, ethyl acetate, and ethyl lactate. Examples of the alcohol compound solvent include n-butanol and isobutanol. Examples of the aromatic compound solvent include benzene, toluene, xylene and the like. Examples of the aliphatic compound solvent include n-hexane and cyclohexane. Examples of the ketone compound solvent include methyl ethyl ketone, acetone, and cyclohexanone.

Of these, ethyl lactate, ethyl acetate, acetone, and ethanol are preferable, and ethyl lactate is more preferable. These may be used alone or in combination of two or more. The third solvent is not the same as the good solvent (first solvent) or the poor solvent (second solvent). In the present invention, when a solvent different from both the good solvent and the poor solvent used as a medium of the composition is generically referred to, this may be referred to as a “third solvent”.
The solvent may further contain other components as required.

The timing of adding the substitution solvent is not particularly limited as long as it is after the precipitation of pigment fine particles, but it is preferably added after the concentration / removal step described above. That is, it is preferable to replace the solvent component composed of the good solvent (first solvent) and the poor solvent (second solvent) in the mixed solution in which the organic nanoparticles are deposited with the replacement solvent (third solvent).
When a pigment dispersion composition to be described later is used, after the first concentration / removal step (first concentration), the third solvent is added to replace the solvent, and the second concentration / removal step (second concentration). It is preferable to reduce the solvent content by concentration) to obtain a concentrated solution, or to remove the solvent content to obtain a powder. And a binder and / or a solvent can be added after that, and it can be set as a desired pigment dispersion composition.
Although the addition amount of the substitution solvent is not particularly limited, it is preferably 100 to 300,000 parts by mass and more preferably 500 to 10,000 parts by mass with respect to 100 parts by mass of the pigment fine particles.

  The pigment fine particles can be used, for example, in a dispersed state in a vehicle. The vehicle refers to a portion of a medium in which a pigment is dispersed when it is in a liquid state, a portion that is liquid and binds to the pigment to harden a coating film (binder). And a component (organic solvent) to be dissolved and diluted. In the present invention, the binder used for nanoparticle formation and the binder used for redispersion may be the same or different.

  In the present invention, the concentration of the pigment particles in the pigment dispersion composition is appropriately determined according to the purpose, but preferably the pigment particles are preferably 2 to 30% by mass with respect to the total amount of the dispersion composition. It is more preferable that it is mass%, and it is especially preferable that it is 5-15 mass%. In the case of dispersing in the vehicle as described above, the amount of the binder and dissolved dilution component is appropriately determined depending on the type of the organic pigment and the like, but the binder is 1 to 30% by mass with respect to the total amount of the dispersion composition. Preferably, it is 3-20 mass%, More preferably, it is 5-15 mass%. It is preferable that a dissolution dilution component is 5-80 mass%, and it is more preferable that it is 10-70 mass%.

In the concentrated nanoparticle liquid with a reduced solvent content, the nanoparticles may aggregate as described above. As a method of redispersing such aggregated nanoparticles, for example, a dispersion method using ultrasonic waves or a method of applying physical energy can be used. The ultrasonic irradiation device used preferably has a function capable of applying an ultrasonic wave of 10 kHz or higher, and examples thereof include an ultrasonic homogenizer and an ultrasonic cleaner. When the liquid temperature rises during ultrasonic irradiation, thermal aggregation of the nanoparticles occurs (see Non-Patent Document 1). Therefore, the liquid temperature is preferably 1 to 100 ° C, more preferably 5 to 60 ° C. The temperature control method can be performed by controlling the dispersion temperature, controlling the temperature of the temperature adjusting layer that controls the temperature of the dispersion, or the like.
There are no particular limitations on the dispersing machine used to disperse the concentrated pigment nanoparticles by applying physical energy. Machine. In addition, a high-pressure dispersion method and a dispersion method using fine particle beads are also preferable.

  The colored photosensitive resin composition includes a dispersion of the organic pigment nanoparticles, a binder, a monomer or an oligomer, and a photopolymerization initiator or a photopolymerization initiator system. Hereinafter, each component of the colored photosensitive resin composition will be described.

  The method for producing the nanometer-sized organic pigment fine particles and the dispersion thereof has already been described in detail. The content of the pigment fine particles is preferably 3 to 90% by mass with respect to the total solid content in the colored photosensitive resin composition (in the present invention, the total solid content refers to the total composition excluding the organic solvent). 20-80 mass% is more preferable, and 25-60 mass% is further more preferable. If this amount is too large, the viscosity of the dispersion increases, which may cause problems in production suitability. If the amount is too small, the coloring power is not sufficient. The pigment nanoparticles (pigment fine particles) functioning as a colorant preferably have a particle size of 0.1 μm or less, particularly 0.08 μm or less. Moreover, you may use it in combination with a normal pigment for toning. As the pigment, those described above can be used.

The monomer or oligomer is preferably a polyfunctional monomer that has two or more ethylenically unsaturated double bonds and undergoes addition polymerization upon irradiation with light. Examples of such monomers and oligomers include compounds having at least one addition-polymerizable ethylenically unsaturated group in the molecule and having a boiling point of 100 ° C. or higher at normal pressure.
Monomers or oligomers may be used alone or in admixture of two or more. The content of the colored photosensitive resin composition with respect to the total solid content is generally 5 to 50% by mass, and 10 to 40% by mass. Is preferred. If this amount is too large, it becomes difficult to control the developability, which causes a problem in production suitability. If the amount is too small, the curing power at the time of exposure is insufficient.

As the binder, a binder having an acidic group is preferable, and it can be added at the time of preparing the inkjet ink or the colored photosensitive resin composition for a color filter, but when producing the pigment dispersion composition or at the time of forming pigment nanoparticles. It is also preferable to add. A binder can also be added to both or one of the poor solvent for adding the organic pigment solution and the organic pigment solution to form pigment nanoparticles. Alternatively, it is also preferable to add the binder solution in a separate system when forming the pigment nanoparticles.
The binder is preferably an alkali-soluble polymer having a polar group such as a carboxylic acid group or a carboxylic acid group in the side chain.
The binder may be used alone or may be used in the state of a composition used in combination with a normal film-forming polymer, and the addition amount relative to 100 parts by mass of pigment fine particles is generally 10 to 200 parts by mass. Yes, 25-100 mass parts is preferable.

As a photopolymerization initiator or a photopolymerization initiator system (in the present invention, a photopolymerization initiator system means a mixture that exhibits a photopolymerization initiation function by a combination of a plurality of compounds). The compound used can be used.
The photopolymerization initiator or the photopolymerization initiator system may be used alone or in combination of two or more, but it is particularly preferable to use two or more. When at least two kinds of photopolymerization initiators are used, display characteristics, particularly display unevenness, can be reduced.
The content of the photopolymerization initiator or the photopolymerization initiator system with respect to the total solid content of the colored photosensitive resin composition is generally 0.5 to 20% by mass, and preferably 1 to 15% by mass. If this amount is too large, the sensitivity becomes too high and control becomes difficult. If the amount is too small, the exposure sensitivity becomes too low.

  In the colored photosensitive resin composition, in addition to the above components, an organic solvent for preparing a resin composition (fourth solvent) may be used, and this may be used as a final solvent. Examples of the fourth solvent include, but are not limited to, esters, ethers, and ketones. Among these solvents, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl cellosolve acetate, ethyl lactate, butyl acetate, methyl 3-methoxypropionate, 2-heptanone, cyclohexanone, ethyl carbitol acetate, butyl carbitol Acetate, propylene glycol methyl ether acetate and the like are preferably used as the solvent. These solvents may be used alone or in combination of two or more. The high-boiling organic solvent can be used as the fourth solvent. For example, a solvent having a boiling point of 180 ° C. to 250 ° C. can be used if necessary. As for content of a 4th solvent, 10-95 mass% is preferable with respect to the resin composition whole quantity.

  The colored photosensitive resin composition can contain a surfactant, a thermal polymerization inhibitor, a colorant (dye, pigment), an ultraviolet absorber, an adhesion aid, other additives, and the like.

The colored photosensitive resin composition can be used as a color filter inkjet ink by appropriately adjusting the composition. When it is set as the inkjet ink for color filters, it is preferable that the said pigment particle, the said monomer or oligomer, and the said binder are included, and it is preferable not to use the said photoinitiator system. At this time, it is preferable to control the ink temperature so that the fluctuation range of the ink viscosity is within ± 5%. The viscosity at the time of injection is preferably 5 to 25 mPa · s, more preferably 8 to 22 mPa · s, and particularly preferably 10 to 20 mPa · s (in the present invention, unless otherwise specified) It is a value at 25 ° C.). In addition to the setting of the injection temperature, the viscosity can be adjusted by adjusting the type and amount of components contained in the ink. The viscosity can be measured, for example, by a normal apparatus such as a conical plate type rotational viscometer or an E type viscometer.
The surface tension of the ink upon ejection is preferably 15 to 40 mN / m from the viewpoint of improving the flatness of the pixel (in the present invention, the surface tension is a value at 23 ° C. unless otherwise specified). ). More preferably, it is 20-35 mN / m, Most preferably, it is 25-30 mN / m. The surface tension can be adjusted by adding a surfactant or the type of solvent. For example, the surface tension is platinum by using a measuring instrument such as a surface tension measuring device (CBVP-Z, manufactured by Kyowa Interface Science Co., Ltd.) or a fully automatic balanced electro surface tension meter ESB-V (manufactured by Kyowa Scientific Co., Ltd.). It can be measured by the plate method.

Ink jet ink for color filters can be sprayed by continuously ejecting charged ink and controlled by an electric field, intermittently ejecting ink using piezoelectric elements, or intermittently using ink by heating and foaming. Various methods such as a method of spraying can be employed.
In addition, regarding the ink jet method used for forming each pixel, a normal method such as a method of thermally curing ink, a method of photocuring, or a method of ejecting droplets after forming a transparent image receiving layer on a substrate in advance. Can be used.

  In the present invention, it is preferable to prepare a partition in advance and apply ink to a portion surrounded by the partition before forming pixels using the color filter inkjet ink. Any partition may be used, but in the case of manufacturing a color filter, it is preferably a light-blocking partition having a black matrix function (hereinafter also simply referred to as “partition”). The partition wall can be produced by the same material and method as those of a normal color filter black matrix.

  Said colored photosensitive resin composition can be apply | coated by the normal apply | coating method, and a coating film can be formed by drying it. Examples of the coating method include coating with a slit nozzle, spin coating, and the like.

  The photosensitive transfer material has a photosensitive resin layer containing the above-described colored photosensitive resin composition, and the specific configuration is not particularly limited. For example, the photosensitive transfer material is formed using an integrated film. It is preferable that As an example of the structure of the integral film, a structure in which a temporary support / thermoplastic resin layer / intermediate layer / photosensitive resin layer / protective film is laminated in this order can be given.

  In the photosensitive transfer material, it is necessary that the temporary support has flexibility and does not cause significant deformation, contraction or elongation even under pressure, or under pressure and heat. Examples of such a temporary support include a polyethylene terephthalate film, a cellulose triacetate film, a polystyrene film, a polycarbonate film, etc. Among them, a biaxially stretched polyethylene terephthalate film is particularly preferable.

  As the component used for the thermoplastic resin layer, organic polymer substances described in JP-A-5-72724 are preferable, and the polymer softening point according to the Viker Vicat method (specifically, the American Material Testing Method ASTM D1 ASTM D1235). It is particularly preferable that the softening point by the measurement method is selected from organic polymer substances having a temperature of about 80 ° C. or less. Specifically, polyolefins such as polyethylene and polypropylene, ethylene copolymers such as ethylene and vinyl acetate or saponified products thereof, ethylene and acrylic acid esters or saponified products thereof, polyvinyl chloride, vinyl chloride and vinyl acetate and saponified products thereof. Vinyl chloride copolymer such as fluoride, polyvinylidene chloride, vinylidene chloride copolymer, polystyrene, styrene copolymer such as styrene and (meth) acrylic acid ester or saponified product thereof, polyvinyl toluene, vinyl toluene and (meta ) Vinyl toluene copolymer such as acrylic ester or saponified product thereof, poly (meth) acrylic ester, (meth) acrylic ester copolymer such as butyl (meth) acrylate and vinyl acetate, vinyl acetate copolymer Combined nylon, copolymer nylon, N-alkoxyme Le nylon, and organic polymeric polyamide resins such as N- dimethylamino nylon.

In the photosensitive transfer material, it is preferable to provide an intermediate layer for the purpose of preventing mixing of components during application of a plurality of application layers and during storage after application. As the intermediate layer, it is preferable to use an oxygen-blocking film having an oxygen-blocking function, which is described as “separation layer” in JP-A-5-72724. This reduces the time load and improves productivity.
The oxygen barrier film is preferably one that exhibits low oxygen permeability and is dispersed or dissolved in water or an aqueous alkali solution, and can be appropriately selected from ordinary ones. Among these, a combination of polyvinyl alcohol and polyvinyl pyrrolidone is particularly preferable.

  It is preferable to provide a thin protective film on the photosensitive resin layer in order to protect it from contamination and damage during storage. The protective film may be made of the same or similar material as the temporary support, but it must be easily separated from the photosensitive resin layer. For example, silicone paper, polyolefin or polytetrafluoroethylene sheet is suitable as the protective film material.

The photosensitive transfer material is provided with a thermoplastic resin layer by applying a coating solution (thermoplastic resin coating solution) in which a thermoplastic resin layer additive is dissolved on a temporary support, followed by drying. An intermediate layer material solution composed of a solvent that does not dissolve the thermoplastic resin layer is applied and dried on the resin layer, and then the photosensitive resin layer is prepared by applying and drying with a solvent that does not dissolve the intermediate layer. Can do.
Also, a sheet provided with the thermoplastic resin layer and the intermediate layer on the temporary support and a sheet provided with the photosensitive resin layer on the protective film are prepared, and the intermediate layer and the photosensitive resin layer are in contact with each other. In addition, a sheet provided with a thermoplastic resin layer on the temporary support and a sheet provided with a photosensitive resin layer and an intermediate layer on a protective film are prepared, and a thermoplastic resin layer is prepared. Can also be produced by bonding them so that the intermediate layer is in contact with each other.

  In the photosensitive transfer material, the thickness of the photosensitive resin layer is preferably 1.0 to 5.0 μm, more preferably 1.0 to 4.0 μm, and particularly preferably 1.0 to 3.0 μm. Further, although not particularly limited, preferred film thicknesses of other layers are 15 to 100 μm for the temporary support, 2 to 30 μm for the thermoplastic resin layer, 0.5 to 3.0 μm for the intermediate layer, and protection. The film is generally preferably 4 to 40 μm.

The color filter of the present invention has a pixel containing the pigment dispersion composition and the graft polymer compound. At this time, the pixels are preferably composed of three colors (R pixel, G pixel, and B pixel), and it is preferable that each pixel is divided and disposed on the substrate with the black matrix as a partition.
The color filter of the present invention is excellent in contrast. In the present invention, the contrast represents the ratio of the amount of transmitted light between two polarizing plates when the polarization axis is parallel and when it is vertical (“1990 Seventh Color Optical Conference, 512-color display 10.4. "Refer to" Color TFT for size TFT-LCD, Ueki, Koseki, Fukunaga, Yamanaka "etc.).
The high contrast of the color filter means that the bright and dark discrimination when combined with the liquid crystal can be increased, and this is a very important performance in order to replace the liquid crystal display with a CRT.

  When the color filter of the present invention is used for a television, the chromaticities of all the single colors of red (R), green (G), and blue (B) by the F10 light source are the values shown in the table below ( Hereinafter, in the present invention, the difference (ΔE) from the “target chromaticity”) is preferably in the range of 5 or less, more preferably 3 or less, and particularly preferably 2 or less.

xy Y
------------------------
R 0.656 0.336 21.4
G 0.293 0.634 52.1
B 0.146 0.088 6.90
------------------------

In the present invention, the chromaticity is measured with a microspectrophotometer (manufactured by Olympus Optical Co., Ltd .; OSP100 or 200), calculated as a result of the F10 light source field of view of 2 degrees, and expressed as an xyY value in the xyz color system. Further, the difference from the target chromaticity is represented by a color difference of the La ^* b ^* color system.

  The liquid crystal display device provided with the color filter of the present invention has a high contrast and excellent descriptive power such as black spots, and is particularly preferably a VA system. It can also be suitably used as a large-screen liquid crystal display device such as a notebook personal computer display or a television monitor. The color filter of the present invention can be used for a CCD device and exhibits excellent performance.

(Examples and comparative examples)
<Pigment dispersion composition A>
To 1500 ml of dimethyl sulfoxide (manufactured by Wako Pure Chemical Industries, Ltd.), 75.0 ml of 28% sodium methoxide methanol solution, pigment C.I. I. Pigment Red 254 (Irgaphor Red BT-CF, trade name, manufactured by Ciba Specialty Chemicals Co., Ltd.) 50 g, and polyvinylpyrrolidone (K-30, trade name, manufactured by Wako Pure Chemical Industries, Ltd.) 90.0 g were added. Pigment solution A (density: 1.0 kg / m ² ) was prepared. As a result of measuring the viscosity of this pigment solution A using Viscomate VM-10A-L (trade name, manufactured by CBC Materials), the viscosity when the liquid temperature of the pigment solution A is 25.0 ° C. is 18. 0 mPa · s. Separately, 2000 ml of water containing 20 ml of 1 mol / l hydrochloric acid (manufactured by Wako Pure Chemical Industries, Ltd.) was prepared as a poor solvent.

  Here, the temperature of the solution was controlled at 25 ° C., and the pigment solution A was added to 2,000 ml of poor solvent water stirred at 500 rpm by a GK-0222-10 type Lamond Stirrer (trade name, manufactured by Fujisawa Pharmaceutical Co., Ltd.). Injection was performed using a large-capacity non-pulsating flow pump (trade name, manufactured by Nippon Seimitsu Chemical Co., Ltd.). By setting the flow path diameter and supply port diameter of the liquid supply pipe of the pigment solution A to 0.8 mm, putting the supply port in a poor solvent, and injecting at a flow rate of 100 ml / min, organic pigment particles are formed, and the pigment dispersion A Was prepared. The number average particle diameter Mn of the pigment nanoparticles in this pigment dispersion A was measured using Nanotrac UPA-EX150 (trade name, manufactured by Nikkiso Co., Ltd.) and found to be 22 nm.

  The pigment dispersion A prepared by the above procedure was concentrated at 5000 rpm for 90 minutes using a H-112 type centrifugal filter manufactured by Kokusan Co., Ltd. and a P89C type cloth manufactured by Shikishima Canvas Co., Ltd., and the resulting pigment was obtained. The nanoparticle concentrated paste was recovered. The pigment content of the paste was measured using an Agilent 8453 type spectrophotometer and found to be 17.2% by mass.

  Next, 13.8 g of the above pigment nanoparticle concentrated paste, 0.1 g of pigment dispersant A synthesized in accordance with JP-A 2000-239554 in 50.0 cc of ethyl lactate, a methacrylic acid / benzyl methacrylate copolymer (molar ratio 28 / 72, mass average molecular weight: 30,000, 40% 1-methoxy-2-propyl acetate solution) 5.94 g was added, and the mixture was stirred with a dissolver at 1500 rpm for 60 minutes. Thereafter, 25.0 cc of ethyl acetate was added, and the mixture was further stirred with a dissolver at 500 rpm for 10 minutes to obtain a dispersion.

  The obtained dispersion was filtered using a FP-010 filter manufactured by Sumitomo Electric Fine Polymer Co., to obtain a paste-like concentrated pigment liquid A (nano pigment concentration 33.4% by mass).

Using the paste, a pigment dispersion composition A having the following composition was prepared.
The paste-like concentrated pigment liquid A 19.3 g
1-methoxy-2-propyl acetate 45.1 g

  The mixture having the above composition was dispersed with a motor mill M-50 (manufactured by Eiger Japan Co., Ltd.) using zirconia beads having a diameter of 0.65 mm for 1 hour at a peripheral speed of 9 m / s to obtain a pigment dispersion composition A.

[Formation of black (K) image]
The alkali-free glass substrate was cleaned with a UV cleaning apparatus, then brush-cleaned with a cleaning agent, and further ultrasonically cleaned with ultrapure water. The substrate was heat-treated at 120 ° C. for 3 minutes to stabilize the surface state.
After cooling the substrate and adjusting the temperature to 23 ° C., it is described in Table 1-1 below with a glass substrate coater (manufactured by FS Asia Co., Ltd., trade name: MH-1600) having a slit-like nozzle. A colored photosensitive resin composition K1 having the composition: Subsequently, a part of the solvent was dried by VCD (vacuum drying apparatus; manufactured by Tokyo Ohka Kogyo Co., Ltd.) for 30 seconds to eliminate the fluidity of the coating layer, and then pre-baked at 120 ° C. for 3 minutes to obtain a film thickness of A 4 μm photosensitive resin layer K1 was obtained.

[Table 1-1]
--------------------------------------
K pigment dispersion 1 (carbon black) 25 parts by mass Propylene glycol monomethyl ether acetate 8.0 parts by mass Methyl ethyl ketone 53 parts by mass Binder 2 9.1 parts by mass Hydroquinone monomethyl ether 0.002 parts by mass DPHA solution 4.2 parts by mass Polymerization start Agent A 0.16 parts by mass Surfactant 1 0.044 parts by mass -------------------------------- ------

In a proximity type exposure machine (manufactured by Hitachi High-Tech Electronics Engineering Co., Ltd.) having an ultra-high pressure mercury lamp, with the substrate and mask (quartz exposure mask having an image pattern) standing vertically, the exposure mask surface and the mask The distance between the photosensitive resin layers was set to 200 μm, and pattern exposure was performed at an exposure amount of 300 mJ / cm ² .
Next, after spraying pure water with a shower nozzle to uniformly wet the surface of the photosensitive resin layer K1, a KOH developer (KOH, containing nonionic surfactant, trade name: CDK-1, (Fujifilm Electronics Materials, Inc., 100-fold diluted solution) was subjected to shower development at 23 ° C. for 80 seconds and a flat nozzle pressure of 0.04 MPa to obtain a patterning image. Subsequently, ultrapure water was sprayed at a pressure of 9.8 MPa with an ultrahigh pressure washing nozzle to remove the residue, and a black (K) image K was obtained. Subsequently, heat treatment was performed at 220 ° C. for 30 minutes.

  For the colored photosensitive resin composition K1, first, K pigment dispersion 1 and propylene glycol monomethyl ether acetate are weighed, mixed at a temperature of 24 ° C. (± 2 ° C.), stirred at 150 rpm for 10 minutes, and then methyl ethyl ketone, binder 2 , Hydroquinone monomethyl ether, DPHA solution, polymerization initiator A (2,4-bis (trichloromethyl) -6- [4 '-(N, N-bisethoxycarbonylmethyl) amino-3'-bromophenyl] -s- Triazine) and surfactant 1 were weighed out, added in this order at a temperature of 25 ° C. (± 2 ° C.), and stirred at 150 rpm for 30 minutes at a temperature of 40 ° C. (± 2 ° C.).

<K pigment dispersion 1>
・ Carbon black (trade name: Nipex 35, manufactured by Degussa Japan Co., Ltd.)
13.1 parts by mass / Pigment Dispersant A 0.65 parts by mass / polymer (benzyl methacrylate / methacrylic acid = 72/28 molar ratio
Random copolymer of, molecular weight 37,000) 6.72 parts by mass / propylene glycol monomethyl ether acetate 79.53 parts by mass

<Binder 2>
・ Polymer (benzyl methacrylate / methacrylic acid = 78/22 molar ratio
Random copolymer of, molecular weight 38,000) 27 parts by mass / propylene glycol monomethyl ether acetate 73 parts by mass <DPHA solution>
・ Dipentaerythritol hexaacrylate (containing polymerization inhibitor MEHQ 500 ppm, Nippon Kayaku Co., Ltd., trade name: KAYARAD DPHA) 76 parts by mass Propylene glycol monomethyl ether acetate 24 parts by mass <Surfactant 1>
MegaFuck F-780-F (manufactured by Dainippon Ink & Chemicals, Inc.): composition is as follows: C ₆ F ₁₃ CH ₂ CH ₂ OCOCH = 40 mass parts of CH ₂ and H (OCH (CH ₃ ) CH ₂ ) ₇ OCOCH = CH ₂ 55 parts by mass and H (OCH ₂ CH ₂ ) ₇ OCOCH = CH ₂ 5 parts by mass (molecular weight 30,000)
30 parts by mass, 70 parts by mass of methyl ethyl ketone

[Formation of red (R) pixels]
Using the colored photosensitive resin composition R1 having the composition described in Table 1-2 below on the substrate on which the image K is formed, the heat-treated pixel R is formed in the same process as the formation of the black (K) image. did. The film thickness of the photosensitive resin layer R1 and the coating amount of the pigment are shown below. In addition, the preparation procedure of the colored photosensitive resin composition was the same as that of the colored photosensitive resin composition K1.
Photosensitive resin film thickness (μm) 1.60
Pigment coating amount (g / m ² ) 1.00
C. I. P. R. 254 coating amount (g / m ² ) 0.80
C. I. P. R. 177 coating amount (g / m ² ) 0.20

[Table 1-2]
--------------------------------------
Pigment dispersion composition A (CIPR254) 40 parts by mass R Pigment dispersion 2 (CIPR177) 4.5 parts by mass Propylene glycol monomethyl ether acetate 7.6 parts by mass Methyl ethyl ketone 37 parts by mass Binder 1 0.7 parts by mass DPHA liquid 3.8 Parts by mass polymerization initiator B 0.12 parts by mass polymerization initiator A 0.05 parts by mass phenothiazine 0.01 parts by mass surfactant 1 0.06 parts by mass -------------- ------------------------

<R pigment dispersion 2>
・ C. I. P. R. 177 (Product name: Chromophthal Red A2B,
Ciba Specialty Chemicals Co., Ltd.) 18 parts by mass Polymer (benzyl methacrylate / methacrylic acid = 72/28 molar ratio)
Random copolymer of, molecular weight 30,000) 12 parts by mass / 70 parts by mass of propylene glycol monomethyl ether acetate <Binder 1>
・ Polymer (benzyl methacrylate / methacrylic acid = 78/22 molar ratio
Random copolymer of, molecular weight 40,000) 27 parts by mass, 73 parts by mass of propylene glycol monomethyl ether acetate <polymerization initiator B>
2-Trichloromethyl- (p-styrylstyryl) 1,3,4-oxadiazole

[Formation of green (G) pixels]
In the same process as the formation of the black (K) image, the heat-treated pixel is formed using the colored photosensitive resin composition G1 having the composition described in Table 1-3 below on the substrate on which the image K and the pixel R are formed. G was formed. The film thickness of the photosensitive resin layer G1 and the coating amount of the pigment are shown below. In addition, the preparation procedure of the colored photosensitive resin composition was the same as that of the colored photosensitive resin composition K1.
Photosensitive resin film thickness (μm) 1.60
Pigment application amount (g / m ² ) 1.92
C. I. P. G. 36 coating amount (g / m ² ) 1.34
C. I. P. Y. 150 coating amount (g / m ² ) 0.58

[Table 1-3]
--------------------------------------
G pigment dispersion 1 (CIPG36) 28 parts by mass Y pigment dispersion 1 (CIPI150) 15 parts by mass Propylene glycol monomethyl ether acetate 29 parts by mass Methyl ethyl ketone 26 parts by mass Cyclohexanone 1.3 parts by mass Binder 2 2.5 parts by mass DPHA solution 3 0.5 part by weight Polymerization initiator B 0.12 part by weight Polymerization initiator A 0.05 part by weight Phenothiazine 0.01 part by weight Surfactant 1 0.07 part by weight ------------ --------------------------

<G pigment dispersion 1>
"Product name: GT-2" manufactured by FUJIFILM Electronics Materials Co., Ltd.
<Y pigment dispersion 1>
"Product name: CF Yellow-EX3393" manufactured by Gokoku Color Co., Ltd.

[Formation of blue (B) pixels]
Using the colored photosensitive resin composition B1 having the composition described in Table 1-4 below on the substrate on which the image K, the pixel R, and the pixel G are formed, A heat-treated pixel B was formed to obtain a color filter A1. The film thickness of the photosensitive resin layer B1 and the coating amount of the pigment are shown below. In addition, the preparation procedure of the colored photosensitive resin composition was the same as that of the colored photosensitive resin composition K1.
Photosensitive resin film thickness (μm) 1.60
Pigment application amount (g / m ² ) 0.75
C. I. P. B. 15: 6 coating amount (g / m ² ) 0.705
C. I. P. V. 23 coating amount (g / m ² ) 0.045

[Table 1-4]
--------------------------------------
B pigment dispersion 1 (CIPB15: 6) 8.6 parts by mass B pigment dispersion 2 (CIPB15: 6 + CIPV23) 15 parts by mass Propylene glycol monomethyl ether acetate 28 parts by mass Methyl ethyl ketone 26 parts by mass Binder 3 17 parts by mass DPHA solution 4.0 Parts by mass polymerization initiator B 0.17 parts by mass phenothiazine 0.02 parts by mass surfactant 0.06 parts by mass ----------------------- ---------------

<B pigment dispersion 1>
"Product name: CF Bull-EX3357" manufactured by Gokoku Color Co., Ltd.
<B pigment dispersion 2>
"Product name: CF Bull-EX3383" manufactured by Gokoku Color Co., Ltd.
<Binder 3>
-Polymer (benzyl methacrylate / methacrylic acid / methyl methacrylate = 36/22/42 molar ratio random copolymer, molecular weight 38,000) 27 parts by mass-propylene glycol monomethyl ether acetate 73 parts by mass [Production of liquid crystal display device]
A liquid crystal display device was manufactured using the color filter A1, and display characteristics were evaluated.
The glass substrate on which the color filter is formed is put into a sputtering apparatus, and 1300 mm thick ITO (indium tin oxide) is vacuum-deposited on the entire surface at 100 ° C., and then annealed at 240 ° C. for 90 minutes to crystallize the ITO. A transparent electrode was formed. A spacer was formed on the ITO transparent electrode produced above by the same method as the spacer forming method described in [Example 1] of JP-A-2004-240335. A liquid crystal alignment control protrusion was formed on the ITO transparent electrode on which the spacer was formed, using the following positive photosensitive resin layer coating solution. However, the following methods were used for exposure, development, and baking. A proximity exposure machine (manufactured by Hitachi High-Tech Electronics Engineering Co., Ltd.) is arranged so that the predetermined photomask is at a distance of 100 μm from the surface of the photosensitive resin layer, and the irradiation energy is 150 mJ / Proximity exposure was performed at cm ² .
・ Positive resist solution (FUJIFILM Electronics
Materials Co., Ltd. FH-2413F): 53.3 parts by mass / Methyl ethyl ketone: 46.7 parts by mass / Megafac F-780F (Dainippon Ink Chemical Co., Ltd.): 0.04 parts by mass

  Subsequently, a 2.38% tetramethylammonium hydroxide aqueous solution was developed by spraying it on a substrate at 33 ° C. for 30 seconds in a shower type developing device. In this way, by removing the unnecessary portion (exposed portion) of the photosensitive resin layer by developing and removing the liquid crystal, the liquid crystal alignment control protrusions made of the photosensitive resin layer patterned into a desired shape are formed on the color filter side substrate. A display device substrate was obtained. Next, the liquid crystal alignment control projection on which the liquid crystal alignment control protrusion was formed was baked at 230 ° C. for 30 minutes to form a cured liquid crystal alignment control protrusion on the liquid crystal display substrate.

An alignment film made of polyimide was further provided on the liquid crystal display substrate obtained above.
After that, an epoxy resin sealant is printed at a position corresponding to a black matrix outer frame provided around the pixel group of the color filter, and MVA mode liquid crystal is dropped and bonded to the counter substrate. The bonded substrate was heat treated to cure the sealant. Polarizing plates HLC2-2518 manufactured by Sanlitz Co., Ltd. were attached to both surfaces of the liquid crystal cell thus obtained. Next, a backlight of a three-wavelength cold-cathode tube light source (FWL18EX-N manufactured by Toshiba Lighting & Technology Co., Ltd.) is constructed and placed on the back side of the liquid crystal cell provided with the polarizing plate. did.

[Measurement of color filter contrast]
The contrast of the red pixel of the color filter A1 obtained above was measured by the following measuring method. As a backlight unit, a cold cathode tube light source (used in a SHARP liquid crystal television LC-22GD3) with a diffusion plate installed was used, and two polarizing plates (polarizing plate POLAX-15N manufactured by Luceo Co., Ltd.) were used. Contrast by dividing the Y value of the chromaticity of the light that passes when the polarizing filter is installed in parallel Nicol with the Y value of the chromaticity of the light that passes when installed in crossed Nicol Asked. A color luminance meter (BM-5A manufactured by Topcon Corporation) was used for the measurement of chromaticity. The two polarizing plates, the color filter, and the color luminance meter are installed at the position of 500 mm through the polarizing plate installed in front of the color luminance meter. It was measured with a color luminance meter installed at the position. The measurement angle of the color luminance meter was set to 2 °. The amount of light from the backlight was set to be maximum. In order to measure the contrast of a single red pixel in the above method, an attachment lens (AL-11 manufactured by Topcon Co., Ltd.) is added to the color luminance meter in the above method, the measurement area is reduced to 60-70 μm, Only the light transmitted through the R pixel was taken into a color luminance meter installed at a position of 50 mm. The results are shown in Table A below.

[Evaluation of burn-in failure of liquid crystal display devices]
With respect to the liquid crystal display device A1, the residual DC voltage generated in the liquid crystal cell is measured by the method for obtaining the optimum common voltage that minimizes the flicker described in FIG. 4B of Japanese Patent Application Laid-Open No. 2000-275645. did. The burn-in failure indicates that the measured value can be suppressed as the residual DC voltage is smaller. Here, when the residual DC voltage is less than 80 mV, “burn-in does not occur”, when it is less than 100 mV, “burn-in occurs slightly”, and when the residual DC voltage is 100 mV or more, “burn-in” occurs. Was evaluated. The results are shown in Table A below.

[Evaluation of display characteristics of liquid crystal display devices]
The display characteristics of the liquid crystal display device A1 (representation of red, presence or absence of red color unevenness when displaying in a single color) were evaluated by a panel of 10 people. Table A shows the average of 10 people in the following stage evaluation.

Red description 5: Excellent red description 4: No problem with red description (good)
3: The depiction of red is slightly unsatisfactory (normal)
2: Depiction of red is unsatisfactory (somewhat bad)
1: Red color reproduction is poor (very bad)
Red color unevenness 5: No red unevenness is seen 4: Red unevenness is no problem (good)
3: A slight unevenness in red is felt (normal)
2: Recognize red unevenness clearly (somewhat bad)
1: Red unevenness is noticeable (very bad)

  The color filter A2 and the liquid crystal display device A1 were prepared in the same manner as in Table A except that the polymer used in forming the pigment particles and the polymer and dispersant used in preparing the pigment dispersion composition were changed as shown in Table A. To A14 and liquid crystal display devices A2 to A14 were produced.

Further, a color filter A15 and a liquid crystal display device A15 were produced in exactly the same manner except that the following pigment dispersion B was used instead of the pigment dispersion composition A used in the production of the color filter A1 and the liquid crystal display device A.
* Pigment dispersion composition B
A pigment dispersion B having the following composition was prepared in the same manner as in Example 2 of JP-A No. 2002-296770.
C. I. Pigment Red 254 6.4g
Disperbyk 161 (trade name, manufactured by BYK Chemie) 16.64 g
1-methoxy-2-propyl acetate 38.16 g
Were mixed and sufficiently dispersed in a sand mill. One end carboxyl group polybenzyl methacrylate (as described in Example 2 of JP-A No. 2002-296770) was obtained in the resulting liquid.
3.2 g was added and mixed, and pigment dispersion composition B was prepared by a breakdown method.

Similarly, a color filter A16 and a liquid crystal display device A16 were produced in the same manner except that the following pigment dispersion C was used instead of the pigment dispersion composition A used in the production of the color filter A1 and the liquid crystal display device A.
* Pigment dispersion composition C
According to the same composition and method as the pigment dispersion G-1 in the examples of JP-A-2002-273191, C.I. I. Pigment green 36, C.I. I. Pigment Yellow 138 is a C.I. I. Pigment dispersion composition C was prepared by the breakdown method in exactly the same manner as pigment dispersion G-1, except that it was replaced with Pigment Red 254 and this weight.

  Table A shows the results of evaluating the contrast, image sticking, and display characteristics of each specimen.

Graft type 1: Graft type polymer compound, Solsperz 24000GR (trade name, manufactured by Lubrizol)
Graft type 2: Graft type polymer compound, Solspers 32000 (trade name, manufactured by Lubrizol)
Graft type 3: Graft type polymer compound, Solspers 32000 (trade name, manufactured by Lubrizol)
Graft type 4: Graft type polymer compound, Disperbyk-161 (trade name, manufactured by BYK Chemie)
Pigment derivative type 1: EFKA6750 (trade name, manufactured by EFKA)
Pigment derivative type 2: Solspers 5000 (trade name, manufactured by Lubrizol)
Terminal modified type 1: Solspers 3000 (trade name, manufactured by Lubrizol)

  From the above results, it is understood that not only a high-contrast color filter can be obtained but also various performances of the color filter in the liquid crystal display device can be improved by using the graft type polymer compound. Although the detailed mechanism of action is unknown, the adsorptive power of the graft polymer is high on the surface of the pigment fine particles deposited by mixing the pigment solution and the poor solvent of the pigment, and the color filter or liquid crystal display device This is considered to be due to the fact that it exhibits a unique action in the dispersion environment of the above-mentioned pigment fine particles, and good fine dispersibility and dispersion stability are maintained.

Claims (7)

  Contains a pigment dispersion composition containing organic pigment particles formed by mixing a solution obtained by dissolving an organic pigment in a good solvent and a poor solvent for the organic pigment compatible with the good solvent, and a graft polymer compound A color filter having pixels to be used.   The color filter according to claim 1, wherein the pigment dispersion composition is substantially free of a solvent component in the mixed liquid in which the organic pigment particles are formed, and includes a different final solvent.   The substitution of the solvent content in the mixed solution to the final solvent is performed once by subtracting or removing the solvent content in the mixed solution and adding a different type of substitution solvent from the solvent content in the mixed solution. The color filter according to claim 1, wherein the color filter is repeated.   The color filter according to claim 1, wherein the pigment dispersion composition is obtained by allowing the graft polymer compound to coexist when the organic pigment particles are formed.   The color filter according to claim 1, wherein the pigment dispersion composition is obtained by containing the graft polymer compound after the formation of the organic pigment particles.   A liquid crystal display device comprising the color filter according to claim 1.   The liquid crystal display device according to claim 6, wherein the liquid crystal display device is a VA system.