TW202344628A - Pigment dispersion composition for black matrix, resist composition for black matrix and black matrix - Google Patents

Abstract

The present invention provides a pigment dispersion composition for a black matrix, which can form a black matrix having an excellent fine line adhesion and a surface resistance while maintaining a development time and a line width in an appropriate range when forming the black matrix. The pigment dispersion composition for a black matrix of this invention includes a black colorant, a pigment dispersant, a binder resin, and an organic solvent. The pigment dispersant has a valerolactone skeleton and an isocyanurate skeleton.

Description

Pigment dispersion composition for black matrix, photoresist composition for black matrix, and black matrix

The present invention relates to a pigment dispersion composition for black matrices, a photoresist composition for black matrices, and a black matrix.

In image display devices using liquid crystal or plasma, etc., a light-shielding film (black matrix) is provided in the gap between the colored patterns in the screen display area or at the edge of the peripheral part of the display area. In addition, in liquid crystal using TFT In the display, a light-shielding film (black matrix) is provided on the external light side of the TFT. Moreover, regarding the role of the light-shielding film (black matrix), in liquid crystal display devices, it mainly prevents light leakage from the backlight from entering the screen, and in plasma display devices, it mainly prevents light leakage caused by turbidity of various colors of light. The colors are projected into the screen, thereby improving display characteristics (contrast and color purity).

For example, a color filter used to convert the white light of the backlight of a liquid crystal display device into colored light is usually manufactured by the following method, that is, on the surface of a transparent substrate such as glass or plastic sheet on which a black matrix is formed, Pixels of different hues of red, green, and blue are formed in striped or mosaic-like patterns.

In addition, in a touch panel that combines an image display device and a position input device, a color filter formed with a black matrix as a light-shielding film is also used. Previously, it was generally formed on the sensor through a cover glass. The side opposite to the detector substrate. However, as the requirements for lightweight touch panels increase, technology is being actively developed to simultaneously form a light-shielding film and a touch sensor on the same side of the cover glass to achieve further lightweighting.

As a method of forming such a black matrix, for example, photolithography using pigments (pigment method) is used.

For example, Patent Document 1 discloses that a composition for forming a light-shielding film using a pigment method includes an inorganic pigment, a black dye, and a dispersant. As the dispersant, a polymer dispersant [for example, polyamide amine and Its salts, polycarboxylic acids and their salts, high molecular weight unsaturated acid esters, modified polyurethane (polyurethane), modified polyester, modified poly(meth)acrylate, (meth)acrylic copolymers and naphthalene sulfonate formalin condensate, etc.], polyoxyethylene alkyl phosphates, polyoxyethylene alkyl amines and pigment derivatives, etc.

In recent years, there has been a demand for a pigment dispersion composition for a black matrix that can maintain the development time and line width within an appropriate range when forming a black matrix, and can form a black matrix with excellent fine line adhesion and surface resistance. Previous black matrix-forming compositions have not been able to obtain compositions that meet all the above requirements, and there is room for further improvement. [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2021-128345

[Problem to be solved by the invention]

Therefore, an object of the present invention is to provide a pigment dispersion composition for a black matrix that can maintain the development time and line width within an appropriate range when forming a black matrix, and can form a black matrix with excellent fine line adhesion and surface resistance value. . [Technical means to solve the problem]

The present inventors discovered that by using a pigment dispersant having a valerolactone skeleton and an isocyanurate skeleton in a black matrix pigment dispersion composition containing a black colorant, a pigment dispersant, and a binder resin, all problems can be solved. The present invention has been completed by solving the above-mentioned problems.

That is, the present invention is a pigment dispersion composition for black matrix, which contains a black colorant, a pigment dispersant, a binder resin and an organic solvent. The above pigment dispersant has a valerolactone skeleton and an isocyanurate skeleton. . In the pigment dispersion composition for black matrix of the present invention, the black colorant preferably has an average primary particle diameter of 20 to 50 nm. Moreover, it is preferable that the pH value of the said black coloring agent is 3.5 or less. In addition, the black colorant preferably has a DBP oil absorption of 75 ml/100 g or less. In addition, the above-mentioned pigment dispersant preferably has an amine value of 5 to 35 mgKOH/g. Moreover, it is preferable to further contain a pigment dispersion aid, and the pigment dispersion aid is a sulfonated product of copper phthalocyanine. In addition, the above-mentioned binder resin is preferably alkali-soluble cardo resin and/or alkali-soluble epoxy (meth)acrylate resin. Furthermore, the present invention is also a photoresist composition for black matrix containing the above-mentioned pigment dispersion composition for black matrix, a photopolymerizable compound and a photopolymerization initiator. Furthermore, the present invention is also a black matrix formed from the above photoresist composition for black matrix. [Effects of the invention]

According to the present invention, it is possible to provide a pigment dispersion composition for a black matrix that can maintain the development time and line width within an appropriate range when forming a black matrix, and can form a black matrix with excellent fine line adhesion and surface resistance value.

<Pigment dispersion composition for black matrix> The pigment dispersion composition for black matrix of the present invention contains a black colorant, a pigment dispersant, a binder resin and an organic solvent, and the above-mentioned pigment dispersant has a valerolactone skeleton and an isocyanurate skeleton.

The pigment dispersion composition for black matrices of the present invention contains a pigment dispersant having a valerolactone skeleton and an isocyanurate skeleton. By having the above-mentioned pigment dispersant have at least the above two kinds of skeletons, the affinity for the binder resin can be improved without impairing the adsorption property to the black colorant. Therefore, the black colorant can also maintain a good dispersion state in the black matrix after film formation. Through the above mechanism, it is possible to obtain a pigment dispersion composition for a black matrix that can maintain the development time and line width within an appropriate range when forming a black matrix, and can form a black matrix with excellent fine line adhesion and surface resistance value. However, the present invention may be interpreted without being limited to the above-mentioned mechanism.

(black colorant) The pigment dispersion composition for black matrices of the present invention contains a black colorant. The above-mentioned black colorant preferably has a pH value of 3.5 or less. By setting the pH value of the above-mentioned black colorant to 3.5 or less, the line width of the formed black matrix can be appropriately maintained, and the fine wire adhesion and surface resistance can be improved more appropriately. The above-mentioned black colorant preferably has a pH value of 3.0 or less.

Furthermore, the above pH value can be measured as follows: add 1 g of carbon black to 20 ml of distilled water (pH value 7.0) from which carbonic acid has been removed, mix with a magnetic stirrer to prepare an aqueous suspension, and use a glass The electrode is used for measurement at 25°C (German industrial product standard DIN ISO 787/9).

The above-mentioned carbon black is preferably acidic carbon black. The acidic carbon black is a carbonaceous substance formed by natural or artificial oxidation. It shows acidity when mixed with distilled water and boiled.

As the above-mentioned black colorant, the average primary particle diameter is preferably 20 to 50 nm, and more preferably the average primary particle diameter is 25 to 45 nm. By setting the average primary particle size of the black colorant to the above range, the line width of the formed black matrix can be appropriately maintained, and the fine wire adhesion and surface resistance can be improved more appropriately. In addition, storage stability can also be imparted appropriately. In addition, the above-mentioned average primary particle diameter is the value of the arithmetic mean diameter obtained by electron microscope observation.

The above-mentioned black colorant preferably has a DBP oil absorption capacity of 75 ml/100 g or less. By setting the DBP oil absorption amount of the above-mentioned black colorant to 75 ml/100 g or less, the line width of the formed black matrix can be appropriately maintained, and the fine wire adhesion and surface resistance can be improved more appropriately. The DBP oil absorption capacity of the black colorant is preferably 60 ml/100 g or less, and further preferably 50 ml/100 g or less.

Furthermore, DBP oil absorption is a value that indirectly quantifies the structure of carbon black by measuring void volume, and is measured in accordance with JIS K 6217-4. Furthermore, "DBP" is the abbreviation of Dibutylphtalate.

Specific examples of the black colorant include Raven 1080 manufactured by Columbia Chemical Company (pH value 2.4, average primary particle diameter 28 nm, DBP oil absorption capacity 60 ml/100 g), Raven 1100U (pH value 2.9, average primary particle diameter Particle size 32 nm, DBP oil absorption capacity 72 ml/100 g), NEROX305 manufactured by Orion Engineered Carbons (pH value 2.8, average primary particle size 28 nm, DBP oil absorption capacity 58 ml/100 g), NEROX3500 (pH value 3.0, Average primary particle size 31 nm, DBP oil absorption capacity 43 ml/100 g), MA14 manufactured by Mitsubishi Chemical Co., Ltd. (pH value 2.8, average primary particle size 40 nm, DBP oil absorption capacity 73 ml/100 g), MA220 (pH value 2.9 , the average primary particle size is 55 nm, DBP oil absorption is 93 ml/100 g), etc.

The content of the black colorant is preferably 5 to 85 mass %, more preferably 10 to 80 mass % based on the mass fraction of the total solid content of the pigment dispersion composition for black matrix of the present invention. If the content of the black colorant is less than 5% by mass, the light-shielding property when forming a black matrix may be reduced, and if it exceeds 85% by mass, dispersion of the pigment may become difficult.

(Pigment dispersant) The pigment dispersion composition for black matrices of the present invention contains a pigment dispersant. The above-mentioned pigment dispersant has a valerolactone skeleton and an isocyanurate skeleton. By having such a skeleton, the affinity for the binder resin can be improved without impairing the adsorption of black colorants. Therefore, in the black matrix after film formation, the black colorant can also maintain a good dispersion state and increase the surface resistance value.

The amine value of the above-mentioned pigment dispersant is preferably 5 to 35 mgKOH/g. By setting the amine value of the above-mentioned pigment dispersant within the above-mentioned range, the viscosity of the pigment-dispersed composition for the black matrix can be reduced, so that the line width of the formed black matrix can be suitably maintained, and fine line adhesion can be more suitably improved. sex. On the other hand, when the amine value of the above-mentioned pigment dispersant is less than 5 mgKOH/g, the pigment dispersion composition for black matrix will be poorly dispersed and become highly viscous. If the amine value of the above-mentioned pigment dispersant exceeds 35 mgKOH/g, g, the viscosity will increase due to the neutralization reaction with the binder resin described below. The above-mentioned pigment dispersant preferably has an amine value of 10 to 30 mgKOH/g. Furthermore, the amine value represents the total amount of free bases and bases, and is expressed in mg of equivalent potassium hydroxide relative to the hydrochloric acid required to neutralize 1 g of the sample.

The above-mentioned pigment dispersant is a pigment dispersant containing an alkaline group. Anionic surfactant, a polyester pigment dispersant containing an alkaline group, an acrylic pigment dispersant containing an alkaline group, anionic surfactant containing an alkaline group, Urethane pigment dispersants, carbodiimide pigment dispersants containing basic groups, polymer pigment dispersants containing acidic groups, etc. These alkaline group-containing pigment dispersants can be used alone or in combination of two or more. Among them, in terms of obtaining good pigment dispersion, a polymer pigment dispersant containing a basic group is preferred.

Specific examples of the above-mentioned pigment dispersants include Solsperse 83500 (amine value of solid content: 25 mgKOH/g, solid content: 40% by mass) manufactured by Lubrizol Corporation of Japan, and Solsperse 82500 (amine value of solid content: 40% by mass). Value 26 mgKOH/g, solid content 50 mass%), etc.

The content of the pigment dispersant is preferably 1 to 200 parts by mass, and more preferably 5 to 100 parts by mass relative to 100 parts by mass of the black colorant.

The above-mentioned pigment dispersant may also contain pigment dispersants other than those having a valerolactone skeleton and an isocyanurate skeleton (hereinafter also referred to as other pigment dispersants).

From the viewpoint of adsorbability to the black colorant, the other pigment dispersant preferably contains a urethane or isocyanurate skeleton.

From the viewpoint of reducing the viscosity of the pigment dispersion composition for black matrices, the amine value of the above-mentioned other pigment dispersants is preferably 5 to 35 mgKOH/g.

The content of the above-mentioned other pigment dispersants is preferably 0 to 150 parts by mass relative to 100 parts by mass of the pigment dispersant having a valerolactone skeleton and an isocyanurate skeleton.

(Pigment dispersion aid) The pigment dispersion composition for black matrix of the present invention preferably contains a pigment dispersion assistant. By containing the above-mentioned pigment dispersion auxiliary, the storage stability and the re-solubility of the black matrix described below can be appropriately imparted.

Examples of the pigment dispersion aid include at least one selected from the group consisting of acid group-containing pigment derivatives and acid group-containing dye derivatives.

Examples of the acid group-containing pigment derivatives and acid group-containing dye derivatives include phthalocyanine-based pigment derivatives that are sulfonated compounds of copper phthalocyanine, anthraquinone-based pigment derivatives having an acid group, and acid group-containing pigment derivatives. Naphthalene pigment derivatives, etc. Among them, from the viewpoint of the dispersibility of the black colorant, a sulfonated compound of copper phthalocyanine is preferred.

Specific examples of the sulfonated compound of copper phthalocyanine include Solsperse 5000S and Solsperse 12000S manufactured by Lubrizol Corporation, BYK-SYNERGIST 2100 manufactured by BYK-Chemie Corporation, and the like.

The content of the above-mentioned pigment dispersion aid is preferably 0 to 20 parts by mass, and more preferably 0.5 to 10 parts by mass relative to 100 parts by mass of the black colorant.

(Binder resin) The pigment dispersion composition for black matrix of the present invention contains a binder resin.

Examples of the binder resin include thermosetting resins, thermoplastic resins, photopolymerizable compounds, alkali-soluble resins, and the like. These can be used individually or in mixture of 2 or more types.

Examples of the thermosetting resin or thermoplastic resin include butyral resin, styrene-maleic acid copolymer, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, and vinyl chloride-vinyl acetate copolymer. Materials, polyvinyl acetate, polyurethane resin, phenol resin, polyester resin, acrylic resin, alkyd resin, styrene resin, polyamide resin, rubber resin, cyclized rubber, epoxy resin, cellulose , polybutadiene, polyimide resin, benzoguanamine resin, melamine resin, urea resin, cardo resin, etc.

Examples of the photopolymerizable compound include monomers having one or more photopolymerizable unsaturated bonds in the molecule, oligomers having a photopolymerizable unsaturated bond, and the like.

As the above-mentioned monomer having one photopolymerizable unsaturated bond in the molecule, for example, methyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, methyl acrylate, Butyl acrylate, 2-ethylhexyl acrylate and other alkyl methacrylates or alkyl acrylates; benzyl methacrylate, benzyl acrylate and other aralkyl methacrylates or aralkyl acrylates; methyl Butoxyethyl acrylate, butoxyethyl acrylate and other alkoxyalkyl methacrylates or alkoxyalkyl acrylates; N,N-dimethylaminoethyl methacrylate, N, acrylate, Methacrylic acid aminoalkyl esters or acrylic acid aminoalkyl esters such as N-dimethylaminoethyl ester; diethylene glycol monoethyl ether, triethylene glycol monobutyl ether, dipropylene glycol monomethyl ether and other polyextensions Methacrylate or acrylate of polyalkylene glycol monoalkyl ether; methacrylate or acrylate of polyalkylene glycol monoaryl ether such as hexaethylene glycol monophenyl ether; isobornyl methacrylate or Isobornyl acrylate, glyceryl methacrylate or glyceryl acrylate, 2-hydroxyethyl methacrylate or 2-hydroxyethyl acrylate, etc.

As the above-mentioned monomer having two or more photopolymerizable unsaturated bonds in the molecule, for example, bisphenol A dimethacrylate, 1,4-butanediol dimethacrylate, 1,3 -Butanediol dimethacrylate, diethylene glycol dimethacrylate, glycerol dimethacrylate, neopentyl glycol dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate Methacrylate, tetraethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, neopentylerythritol trimethacrylate, neopenterythritol tetramethacrylate, dineopenterythritol Alcohol tetramethacrylate, dipenterythritol hexamethacrylate, dipenterythritol pentamethacrylate, epoxy methacrylate, bisphenol A diacrylate, 1,4-butanediol Diacrylate, 1,3-butanediol diacrylate, diethylene glycol diacrylate, glycerol diacrylate, neopentyl glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, Tetraethylene glycol diacrylate, trimethylolpropane triacrylate, neopentylerythritol triacrylate, neopentylerythritol tetraacrylate, dineopenterythritol tetraacrylate, dineopenterythritol hexaacrylate , dipenterythritol pentaacrylate, epoxy acrylate, etc.

As the above-mentioned oligomer having a photopolymerizable unsaturated bond, those obtained by suitably polymerizing the above-mentioned monomers can be used. The above-mentioned binder resins can be used alone or in combination of two or more types.

The above-mentioned alkali-soluble resin will be described below.

From the viewpoint of appropriately maintaining the development time when forming the black matrix, the binder resin is preferably alkali-soluble cardo resin and/or alkali-soluble epoxy (meth)acrylate resin. Furthermore, the above-mentioned cardo resin means a resin having a skeleton structure in which two aromatic rings are bonded to carbon atoms in the ring.

From the viewpoint of pigment dispersibility and alkali developability, the above-mentioned binder resin preferably has an acid value of 10 to 200 mgKOH/g, more preferably 50 to 150 mgKOH/g.

In addition, the acid value of the binder resin means the acid value measured by JIS K5601-2-1:1999.

The content of the above-mentioned binder resin is preferably 3 to 50 mass % in terms of mass fraction relative to the total solid content of the pigment dispersion composition for black matrix of the present invention.

(organic solvent) The pigment dispersion composition for black matrix of the present invention preferably contains an organic solvent. As the above-mentioned organic solvent, organic solvents conventionally used in the field of photoresists for liquid crystal black matrices can be suitably used.

The above-mentioned organic solvent is specifically an ester-based organic solvent, an ether-based organic solvent, an ether-ester-based organic solvent, a ketone-based organic solvent, and an aromatic solvent having a boiling point of ¹⁰⁰ to 250°C at normal pressure (1.013×10 2 kPa). Hydrocarbon-based organic solvents, nitrogen-containing organic solvents, etc. If a large amount of the above-mentioned organic solvent with a boiling point exceeding 250° C. is contained, the organic solvent may It may not be fully evaporated and remain in the dry coating film, thereby reducing the heat resistance of the dry coating film. In addition, if a large amount of the above-mentioned organic solvent having a boiling point of less than 100° C. is contained, it may be difficult to apply uniformly without spots, and a coating film with excellent surface smoothness may not be obtained.

Specific examples of the organic solvent include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, and diethyl glycol. Ether-based organic solvents such as glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether; Ether ester organic solvents such as glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, and propylene glycol monoethyl ether acetate; Ketone-based organic solvents such as isobutyl ketone, cyclohexanone, 2-heptanone, and δ-butyrolactone; methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, 2-hydroxy-2-methyl Propionate, 3-methyl-3-methoxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, 3- Ester-based organic solvents such as ethoxypropionate, ethoxyethyl acetate, ethyl glycolate, n-amyl formate, etc.; alcohol-based solvents such as methanol, ethanol, isopropanol, butanol, etc.; N-methylpyrrole Nitrogen-containing organic solvents such as ridinone, N,N-dimethylformamide, N,N-dimethylacetamide, etc. These can be used individually or in mixture of 2 or more types.

Among the above-mentioned organic solvents, in terms of solubility, dispersibility, coating properties, etc., diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, and ethylene glycol monomethyl ether acetic acid are preferred. Esters, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, cyclohexanone, 2-heptanone, ethyl 2-hydroxypropionate, 3-methyl-3-methoxypropanate acid ester, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, n-amyl formate, etc., and more preferably propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate.

(Method for manufacturing pigment dispersion composition for black matrix) The method of producing the pigment dispersion composition for black matrix of the present invention is not particularly limited. For example, it can be produced by mixing and grinding a black colorant, a pigment dispersant, a pigment dispersion auxiliary and a binder resin.

The above-mentioned black colorant, pigment dispersant, pigment dispersion assistant and binder resin can use the above-mentioned materials.

As a method of performing the above-mentioned mixing and grinding, it is sufficient to add the above-mentioned various ingredients and mix and grind them. The method of performing the above-mentioned grinding is not particularly limited as long as, for example, a bead mill or a pre-mill is used. (Ready Mill), ultrasonic homogenizer, high-pressure homogenizer, coating oscillator, ball mill, roller mill, sand mixer (sand mill), sand grinder (sand grinder), power mill (DYNO-MILL), dispersion Dispermat, SC mill, Nanomizer, etc., and mix and grind by known methods.

(viscosity) The pigment dispersion composition for black matrix of the present invention preferably has a viscosity of 12 mPa·s or less, more preferably 11.5 mPa·s or less, further preferably 10.5 mPa·s or less. The lower limit of the above viscosity is preferably 2.5 mPa·s. By keeping the viscosity within the above range, the line width of the formed black matrix can be appropriately maintained, and the fine line adhesion can be more appropriately improved.

The pigment dispersion composition for black matrix of the present invention is preferably collected into a glass bottle, tightly sealed and stored at 60°C for 1 week. The viscosity change rate [(viscosity after 1 week of storage - viscosity before storage)/(before storage) viscosity)] is less than 10%, preferably less than 5%. If the above-mentioned viscosity change rate is 10% or less, storage stability is excellent and deterioration is unlikely to occur even if stored for a long period of time.

Furthermore, in this specification, viscosity means the viscosity measured at 25°C using an E-type viscometer (R100 viscometer, model RE100L, manufactured by Toki Industrial Co., Ltd.).

＜Photoresist composition for black matrix＞ The present invention also provides a photoresist composition for black matrices obtained from the pigment dispersion composition for black matrices of the present invention.

(Pigment dispersion composition for black matrix) The photoresist composition for black matrices of the present invention contains the above-mentioned pigment dispersion composition for black matrices of the present invention. The content of the pigment dispersion composition for black matrix is preferably 30 to 80 mass %, more preferably 40 to 75 mass % based on the total mass of the photoresist composition for black matrix of the present invention.

(Photopolymerization Initiator) The photoresist composition for black matrix of the present invention preferably contains a photopolymerization initiator. The above-mentioned photopolymerization initiator is not particularly limited as long as it can generate radicals or cations by irradiating active energy rays such as ultraviolet rays or electron beams. For example, 1-[9-ethyl-6 -(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(O-acetyl oxime)ethanone, benzophenone, N,N'-tetraethyl-4, 4'-Diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 2,2-diethoxyacetophenone, benzoin, benzoin methyl ether, benzoin isobutyl Ether, benzildimethyl ketal, α-hydroxyisobutylphenone, 9-oxosulfide , 2-Chloro-9-oxysulfide , 1-hydroxycyclohexylphenyl ketone, 3-butylanthraquinone, 1-chloroanthraquinone, 2,3-dichloroanthraquinone, 3-chloro-2-methylanthraquinone, 2-ethylanthraquinone, 1,4-naphthoquinone, 1,2-benzoanthraquinone, 1,4-dimethylanthraquinone, 2-phenylanthraquinone, 2-methyl-1[4-(methylthio)phenyl] -2-Morpholinopropane-1-one (2-methyl-1-(4-methylthie phonyl)-2-morpholinopropane-1-on) and other benzophenones, 9-oxysulfide𠮿 series, anthraquinone series, three It is a photopolymerization initiator etc. The above-mentioned photopolymerization initiator can be used alone or in combination of two or more kinds.

The content of the above-mentioned photopolymerization initiator is preferably 1 to 20 mass % in terms of mass fraction relative to the total solid content of the photoresist composition for black matrix of the present invention.

(Photopolymerizable compound) The photoresist composition for black matrix of the present invention preferably contains a photopolymerizable compound. As the above-mentioned photopolymerizable compound, those described in the above-mentioned pigment dispersion composition for black matrix can be appropriately selected and used.

The content of the above-mentioned photopolymerizable compound is preferably 0.1 to 50 mass % in terms of mass fraction relative to the total solid content of the photoresist composition for black matrix of the present invention.

(Alkali-soluble resin) The photoresist composition for black matrix of the present invention preferably contains an alkali-soluble resin. The alkali-soluble resin preferably functions as a binder for the black colorant and is soluble in the developer used in the development process when producing the black matrix, especially in the alkali developer.

The alkali-soluble resin may be a block copolymer. By using block copolymers, the pigment dispersion ability can be improved compared to other copolymers, and solubility in PGMEA or alkali developers can be imparted. Among the block copolymers, a copolymer having a block composed of an ethylenically unsaturated monomer having one or more carboxyl groups and other copolymerizable ethylenically unsaturated monomers is preferred. A block composed of monomers.

The block copolymer is not particularly limited, and those conventionally used can be used. Among them, specific examples include copolymerization of an ethylenically unsaturated monomer having a carboxyl group such as acrylic acid and methacrylic acid and at least one ethylenically unsaturated monomer copolymerizable with an ethylenically unsaturated monomer having a carboxyl group. The above-mentioned at least one ethylenically unsaturated monomer that can be copolymerized with an ethylenically unsaturated monomer having a carboxyl group is selected from the group consisting of styrene, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, and vinyl acrylate. Propyl ester, allyl methacrylate, benzyl acrylate, benzyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, glyceryl monoacrylate, glyceryl methacrylate, N-phenylmaleyl A group of monomers and oligomers such as imine, polystyrene macromonomer, polymethylmethacrylate macromonomer, carbonyl epoxy diacrylate, etc. However, it is preferable not to use N-vinylpyrrolidone or a sulfur element-containing monomer. As the above-mentioned block copolymer, a block resin synthesized by living radical polymerization or anionic polymerization can be used. A part of the block part of the above-mentioned block copolymer may also be composed of a random copolymer.

As the above-mentioned alkali-soluble resin, alkali-soluble cardo resin can also be used. Examples of the alkali-soluble cardo resin include epoxy (meth)acrylic acid having a fluorine skeleton which is an addition product of a fluorine epoxy (meth)acrylic acid derivative and a dicarboxylic anhydride and/or a tetracarboxylic dianhydride. Ester acid adducts, etc. Furthermore, the present alkali-soluble resin may have a photopolymerizable functional group.

The acid value of the above-mentioned alkali-soluble resin is preferably 5 to 300 mgKOH/g, more preferably 5 to 250 mgKOH/g, and still more preferably 10 to 200 mgKOH/g, from the viewpoint of development characteristics. It is 60~150 mgKOH/g. In addition, in this specification, the above-mentioned acid value is a theoretical acid value, which is a value calculated arithmetically based on the ethylenically unsaturated monomer having a carboxyl group and its content.

From the viewpoint of developing characteristics and solubility in organic solvents, the weight average molecular weight of the alkali-soluble resin is preferably 1,000 to 100,000, more preferably 3,000 to 50,000, and still more preferably 5,000 to 30,000. In addition, in the present invention, the above-mentioned weight average molecular weight is a weight average molecular weight in terms of polystyrene obtained based on GPC. In this specification, Water2690 (manufactured by Waters Co., Ltd.) is used as a device for measuring the weight average molecular weight, and PLgel 5 μm MIXED-D (manufactured by Agilent Technologies Co., Ltd.) is used as a column.

The content of the alkali-soluble resin is preferably 1 to 200 parts by mass, and more preferably 10 to 150 parts by mass relative to 100 parts by mass of the black colorant. In this case, if the content of the above-mentioned alkali-soluble resin is less than 1 part by mass, the development characteristics may be reduced. If the content of the above-mentioned alkali-soluble resin exceeds 200 parts by mass, the concentration of the above-mentioned black colorant will be relatively reduced, and it may be difficult to Achieve the target color density as a thin film.

The alkali-soluble resin preferably does not contain any of primary, secondary and tertiary amine groups, and furthermore does not contain quaternary ammonium groups. Still more preferably, it does not have a basic group. Furthermore, alkali-soluble resins having structures other than block copolymers may be blended within the scope that does not impair the effects of the present invention.

(organic solvent) As the above-mentioned organic solvent, the organic solvent described in the above-mentioned pigment dispersion composition for black matrix can be appropriately selected and used.

As for the content of the above-mentioned organic solvent, based on the total mass of the photoresist composition for black matrix of the present invention, it is preferably 1 to 40 mass %, and more preferably 5 to 35 mass %.

(Other additives) The photoresist composition for black matrix of the present invention may appropriately use various additives such as thermal polymerization inhibitors, ultraviolet absorbers, and antioxidants as necessary.

(Method for manufacturing the photoresist composition for black matrix) As a method for manufacturing the photoresist composition for black matrix of the present invention, for example, the pigment dispersion composition for black matrix of the present invention can be prepared, and then the remaining materials can be added and Stir and mix using a stirring device etc. to prepare. The method of stirring and mixing is not particularly limited, and known methods such as ultrasonic dispersers, high-pressure emulsifiers, bead mills, three-roller mills, sand mixers, and kneaders can be used. Moreover, you may filter with a filter after the said stirring and mixing. Furthermore, when preparing the photoresist composition for black matrix of the present invention, the above-mentioned black colorant, the above-mentioned epoxy resin, and the above-mentioned epoxy resin described in the pigment dispersion composition for black matrix of the present invention may also be added if necessary. Compounds etc.

＜Black Matrix＞ The black matrix of the present invention is formed from the photoresist composition for black matrix of the present invention.

The method for forming the black matrix of the present invention is not particularly limited. For example, the black matrix can be formed by the following methods: that is, coating the photoresist composition for black matrix of the present invention on a transparent substrate and drying it, After the coating film is formed, a photomask is placed on the coating film, and image exposure and development are performed through the photomask, and if necessary, photohardening is performed.

The methods of applying, drying, exposing and developing the photoresist composition for black matrix of the present invention can be appropriately selected from known methods. In addition, as the transparent substrate, a known transparent substrate such as a glass substrate or a plastic substrate can be appropriately selected and used.

The thickness of the coating film is preferably 0.2 to 10 μm, more preferably 0.5 to 6 μm, and even more preferably 1 to 4 μm in terms of film thickness after drying. By setting the thickness within the above range, a predetermined pattern can be developed appropriately and a predetermined optical density can be appropriately imparted.

Regarding the black matrix of the present invention, the development time can be maintained within an appropriate range when forming the black matrix. Specifically, regarding the black matrix of the present invention, the development time when developing by the following method is in the range of 20 seconds to 45 seconds. If the development time is less than 20 seconds, the hardened part may be excessively invaded by the developer, resulting in poor adhesion of thin lines. If the development time exceeds 45 seconds, the unhardened part may become insufficiently dissolved, resulting in glass Development residue is generated on the substrate. Therefore, it can be judged that if the development time is in the range of 20 seconds to 45 seconds, the appropriate development time can be maintained. The above-mentioned development time is preferably in the range of 30 seconds to 40 seconds.

The method for measuring the above development time is as follows. The black matrix photoresist composition was coated on the glass substrate (product name: EAGLE XG, manufactured by Corning Company) with a film thickness of 1 μm using a spin coater and pre-baked at 100°C for 3 minutes. Then, a photomask with a line pattern with an interval of 1 μm (1 to 20 μm, 20 types in 1 μm units; 30 to 100 μm, 8 types of line widths in 10 μm units) was used, and the process was performed under a high-pressure mercury lamp. Exposure (UV cumulative light amount 80 mJ/cm ² ). Thereafter, the exposed glass substrate was spray developed at 23°C, 0.05% potassium hydroxide aqueous solution, and 0.5 kgf/cm ² pressure, and spray-washed at 3.0 kgf/cm ² pressure. The time from the start of spray development until the black matrix composition in the center of the glass substrate is completely dissolved is measured.

Regarding the black matrix of the present invention, the line width can be maintained within an appropriate range when forming the black matrix. Specifically, the line width measured by the following method is 16.5 μm ~ 21.0 μm. If the line width is such, it can be judged to be maintained within an appropriate range. The line width measured by the above method is preferably 18.5 μm or more, more preferably 19.0 μm or more, and further preferably 19.5 μm or more. Furthermore, the thickness is preferably 21 μm or less, more preferably 20.5 μm or less, and still more preferably 20.3 μm or less.

The above line width is measured by the following method. After the glass substrate for which the above development time was measured was post-baked at 230°C for 30 minutes, the 20 μm pattern line width on the above glass substrate was measured using a digital microscope (product name: VHX-500, manufactured by Keyence Corporation). Determination.

The black matrix of the present invention has excellent fine wire adhesion. Specifically, the fine wire adhesion measured by the following method is 15 μm or less. If it has such thin wire adhesion, it can be judged that the thin wire adhesion is excellent. The fine wire adhesion is preferably 14 μm or less, more preferably 12 μm or less, further preferably 10 μm or less.

The above-mentioned thin wire adhesion is measured by the following method. The above-mentioned photoresist composition for black matrix is coated on the glass substrate (product name: EAGLE . Then, a photomask with a line pattern with an interval of 1 μm (1 to 20 μm, 20 types in 1 μm units; 30 to 100 μm, 8 types of line widths in 10 μm units) was used, and the process was performed under a high-pressure mercury lamp. Exposure (UV cumulative light amount 80 mJ/cm ² ). Through spray development at 23°C, 0.05% potassium hydroxide aqueous solution, and 1 kgf/cm ² , development starts from the time when the development pattern begins to appear (image development time) and ends when the development time reaches 30 seconds. After development, perform spray water washing at a pressure of 1 kgf/ ^cm2 . The width (μm) of the smallest remaining line pattern on the above-mentioned glass substrate was evaluated.

The black matrix of the present invention has excellent surface resistance value. Specifically, if the surface resistance value measured by the following method is 5.0E+11Ω or more, it can be evaluated that the surface resistance value is excellent. The above-mentioned surface resistance value is preferably 1.0E+12 Ω or more, more preferably 3.0E+12 Ω or more, and further preferably 5.0E+12 Ω or more.

The above surface resistance value is measured by the following method. The black matrix photoresist composition was coated on the glass substrate (product name: EAGLE XG, manufactured by Corning Company) with a film thickness of 1 μm using a spin coater and pre-baked at 100°C for 3 minutes. Then, it was exposed with a high-pressure mercury lamp (UV cumulative light intensity 80 mJ/cm ² ), and then baked at 230°C for 180 minutes to produce a black photoresist pattern (black matrix) formed only of solid parts. Thereafter, the surface resistance value of the produced black matrix was measured using a microampere meter R8340 as a main body and a shielding box R12702A as an option (both manufactured by Advance Company).

The black matrix of the present invention is preferably excellent in re-solubility. The re-solubility is evaluated by measuring the OD value described below. If the OD value is 0.5 or less, the re-solubility is judged to be excellent. The black matrix photoresist composition was coated on the glass substrate (product name: EAGLE XG, manufactured by Corning Company) with a film thickness of 1 μm using a spin coater and pre-baked at 100°C for 3 minutes. Next, the unexposed coating film formed on the glass substrate was immersed in PGMEA for 2 minutes. After drying the immersed part, the OD value was measured using a Macbeth concentration meter (TD-931, manufactured by Macbeth Corporation). The above-mentioned OD value is more preferably 0.3 or less.

Since the pigment dispersion composition for black matrices, the photoresist composition for black matrices, and the black matrix of the present invention have the above characteristics, they can be suitably used as black matrices for image display devices, touch panels, and the like. [Example]

Hereinafter, the present invention will be specifically described using examples, but the present invention is not limited to these as long as it does not deviate from the gist and scope of application. Furthermore, unless otherwise specified, in this embodiment, "parts" and "%" represent "mass parts" and "mass %" respectively.

Various materials used in the following examples and comparative examples are as follows. ＜Black colorant＞ NEROX3500 (carbon black, average primary particle size 31 nm, pH value 3.0, DBP oil absorption 43 ml/100 g, manufactured by Orion Engineered Carbons) ＜Pigment dispersant＞ Solsperse83500 (amine value of solid content 25 mgKOH/g, solid content 40% by mass, containing valerolactone skeleton and isocyanurate skeleton, manufactured by Lubrizol Corporation of Japan) Solsperse82500 (amine value of solid content 26 mgKOH/g, solid content 50% by mass, containing valerolactone skeleton and isocyanurate skeleton, manufactured by Lubrizol Corporation of Japan) DISPERBYK-167 (amine value of solid content 24 mgKOH/g, solid content 52% by mass, no valerolactone skeleton, containing caprolactone skeleton and isocyanurate skeleton, manufactured by BYK-Chemie) DISPERBYK-2163 (amine value of solid content 23 mgKOH/g, solid content 45% by mass, no valerolactone skeleton, containing isocyanurate skeleton, manufactured by BYK-Chemie) DISPERBYK-161 (amine value of solid content 36.7 mgKOH/g, solid content 30% by mass, no valerolactone skeleton, containing caprolactone skeleton and isocyanurate skeleton, manufactured by BYK-Chemie) AFCONA-4067 (Amine value of solid content 27 mgKOH/g, does not contain valerolactone skeleton or isocyanurate skeleton, contains urethane skeleton, solid content 45 mass%, manufactured by BASF) LPN21324 (Amine value of solid content 0 mgKOH/g, solid content 40% by mass, does not contain valerolactone skeleton or isocyanurate skeleton, contains acrylic skeleton, manufactured by BYK-Chemie) ＜Pigment dispersion aid＞ Solsperse5000S (quaternary ammonium salt of copper phthalocyanine sulfonate, manufactured by Lubrizol Company) ＜Binder resin＞ ZCR-1569H (epoxy acrylate resin, acid value 100 mgKOH/g, solid content 70 mass%, manufactured by Nippon Chemical Co., Ltd.) ＜Organic solvent＞ PGMEA (propylene glycol monomethyl ether acetate) ＜Photopolymerization initiator＞ OXE02 (Product name "Irgacure OXE02", 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(O-acetyl oxime) B Ketone, manufactured by BASF Corporation) ＜Photopolymerizable compound＞ DPHA (dineopenterythritol hexaacrylate) ＜Alkali-soluble resin＞ WR-301 (Product name "WR-301", cardo resin, acid value 100 mgKOH/g, solid content 45% by mass, manufactured by ADEKA)

<Pigment dispersion composition for black matrix> Each material was mixed so as to have the composition shown in Table 1, and kneaded with a bead mill for a day and night to prepare a pigment dispersion composition for a black matrix.

[Table 1] Pigment dispersion composition for black matrix Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5 black colorant NEROX3500 25.00 25.00 25.00 25.00 25.00 25.00 25.00 25.00 25.00 25.00 25.00 Pigment dispersant Solsperse83500 2.50 - 1.25 3.25 4.00 2.50 - - - - - Solsperse82500 - 2.50 - - - - - - - - - DISPERBYK-167 - - 1.25 - - - 2.50 - - - - DISPERBYK-2163 - - - - - - - 2.50 - - - DISPERBYK-161 - - - - - - - - 2.50 - - AFCONA-4067 - - - - - - - - - 2.50 - LPN21324 - - - - - - - - - - 2.50 Pigment dispersion aid Solsperse5000S 0.75 0.75 0.75 0.75 0.75 - 0.75 0.75 0.75 0.75 0.75 Adhesive resin ZCR-1569H 3.75 3.75 3.75 3.75 3.75 3.75 3.75 3.75 3.75 3.75 3.75 organic solvent PGMEA 68.00 68.00 68.00 67.25 66.50 68.75 68.00 68.00 68.00 68.00 68.00 Total (mass %) 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00

＜Photoresist composition for black matrix＞ Using a high-speed mixer, the above-described pigment dispersion composition for black matrix and other materials (photopolymerization initiator, photopolymerizable compound, alkali-soluble resin, and organic solvent) were uniformly mixed so as to have a composition shown in Table 2. Thereafter, it was filtered with a filter with a pore size of 3 μm to prepare black matrix photoresist compositions of Examples and Comparative Examples. In addition, in Table 2, the numerical value in the right column of each material of a photopolymerization initiator, a photopolymerizable compound, an alkali-soluble resin, and an organic solvent shows the blending amount.

＜Evaluation test＞ (viscosity) The viscosity of the prepared pigment dispersion composition for black matrix was measured at 25°C using an E-type viscometer (R100 viscometer, model RE100L manufactured by Toki Industrial Co., Ltd.). The results are shown in Table 2.

(viscosity stability) The prepared pigment dispersion composition for black matrix was collected into a glass bottle, tightly tied, and stored at 60° C. for 1 week. Before and after the above storage, use an E-type viscometer (R100 viscometer, model RE100L manufactured by Toki Industrial Co., Ltd.) to measure the viscosity at 25°C, and calculate the viscosity change rate [(viscosity after 1 week of storage - before storage) (viscosity)/(viscosity before storage)], and evaluate according to the following evaluation criteria. The results are shown in Table 2. (Evaluation criteria) ○: The viscosity change rate is 5% or less. △: The viscosity change rate exceeds 5% but is less than 10%. ×: The viscosity change rate exceeds 10%.

(Development time) The produced photoresist composition for black matrix is coated on a glass substrate (product name: EAGLE Pre-bake at ℃ for 3 minutes. Then, a photomask with a line pattern with an interval of 1 μm (1 to 20 μm, 20 types in 1 μm units; 30 to 100 μm, 8 types of line widths in 10 μm units) was used, and the process was performed under a high-pressure mercury lamp. Exposure (UV cumulative light amount 80 mJ/cm ² ). Thereafter, the exposed glass substrate was spray developed at 23°C, 0.05% potassium hydroxide aqueous solution, and 0.5 kgf/cm ² pressure, and spray-washed at 3.0 kgf/cm ² pressure. The time from the start of spray development until the black matrix composition in the center of the glass substrate is completely dissolved is measured, and this is regarded as the development time. The results are shown in Table 2.

(line width) After the glass substrate for which the above development time was measured was post-baked at 230°C for 30 minutes, the 20 μm pattern line width on the above glass substrate was measured using a digital microscope (product name: VHX-500, manufactured by Keyence Corporation). Determination. The results are shown in Table 2.

(Fine line adhesion) The produced black matrix photoresist composition was coated on a glass substrate (product name: EAGLE XG, manufactured by Corning Corporation) with a film thickness of 1 μm using a spin coater, and then Pre-bake at 100℃ for 3 minutes. Then, a photomask with a line pattern with an interval of 1 μm (1 to 20 μm, 20 types in 1 μm units; 30 to 100 μm, 8 types of line widths in 10 μm units) was used, and the process was performed under a high-pressure mercury lamp. Exposure (UV cumulative light amount 80 mJ/cm ² ). Thereafter, through spray development under the conditions of 23°C, 0.05% potassium hydroxide aqueous solution, and 1 kgf/ ^cm2 pressure, development starts from the time when the development pattern begins to appear (image development time), and the development time becomes 30 seconds. Then end the development. After development, spray water washing at a pressure of 1 kgf/ ^cm2 was performed, and the width (μm) of the smallest remaining line pattern on the above-mentioned glass substrate was evaluated. The results are shown in Table 2.

(Surface resistance value) The produced photoresist composition for black matrix was coated on a glass substrate (product name: EAGLE XG, manufactured by Corning Company) with a film thickness of 1 μm using a spin coater, and then Pre-bake at 100℃ for 3 minutes. Then, it was exposed with a high-pressure mercury lamp (UV cumulative light intensity 80 mJ/cm ² ), and then baked at 230°C for 180 minutes to produce a black photoresist pattern (black matrix) formed only of solid parts. Thereafter, the surface resistance value of the produced black matrix was measured using a microampere meter R8340 as a main body and a shielding box R12702A as an option (both manufactured by Advance Company). The results are shown in Table 2.

(resolubility) The produced photoresist composition for black matrix was coated on the glass substrate (product name: EAGLE 3 minutes. Next, the unexposed coating film formed on the glass substrate was immersed in PGMEA for 2 minutes. After drying the immersed part, the OD value was measured with a Macbeth concentration meter (TD-931, manufactured by Macbeth Co., Ltd.), and the evaluation was performed according to the following evaluation standards. The results are shown in Table 2. (Evaluation criteria) ◎: 0.3 or less. ○: More than 0.3 but less than 0.5. Δ: More than 0.5 but less than 1.0. ×: greater than 1.0.

[Table 2] Photoresist composition for black matrix Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Comparative example 6 Comparative example 7 Comparative example 8 Comparative example 9 Comparative example 10 Pigment dispersion composition for black matrix Kind Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5 Blending amount 51.00 51.00 51.00 51.00 51.00 51.00 51.00 51.00 51.00 51.00 51.00 Photopolymerization initiator OXE02 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 photopolymerizable compound DPHA 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 alkali soluble resin WR-301 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 4.00 organic solvent PGMEA 42.00 42.00 42.00 42.00 42.00 42.00 42.00 42.00 42.00 42.00 42.00 Total (mass %) 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 Pigment dispersion composition for black matrix Viscosity [mPa・s] 11.5 9.9 10.5 9.2 8.9 10.5 9.5 8.4 Poor dispersion 7.7 6.0 Viscosity stability ○ ○ ○ ○ △ △ ○ ○ ○ × black matrix Development time [seconds] 38 42 38 30 twenty two 40 39 28 - twenty one 27 Line width [μm] 20.28 20.30 20.35 18.99 16.99 20.66 20.36 - - - 24.55 Thin wire adhesion [μm] 8 8 8 12 14 8 8 100 - 50 14 Surface resistance [Ω] 5.5E＋12 1.1E＋12 8.9E＋11 5.1E＋12 3.3E＋12 6.6E+11 3.0E＋11 2.6E＋08 - 1.1E＋11 1.8E＋14 resolubility ○ ○ ◎ ○ ○ △ ◎ △ - × ○

Regarding the example in which the pigment dispersant has a specific skeleton in a pigment dispersion composition for a black matrix containing a black colorant, a pigment dispersant, a binder resin and an organic solvent, it was confirmed that the development time can be reduced when forming the black matrix. And the line width is maintained within an appropriate range, and a black matrix with excellent fine line adhesion and surface resistance can be formed. On the other hand, for comparative examples that did not use a pigment dispersant with a specific skeleton, evaluations were poor in either the development time and line width when forming a black matrix, or the fine line adhesion and surface resistance value of the black matrix. . In addition, since the pigment dispersion composition for black matrix of Comparative Example 3 was not dispersed, it was described as "poor dispersion", and the evaluation test in the black matrix was not performed. In addition, regarding Comparative Examples 7 and 9, since the 20 μm thin wire used for line width evaluation did not remain on the substrate, the line width could not be evaluated. [Industrial availability]

According to the present invention, it is possible to provide a pigment dispersion composition for a black matrix that can maintain the development time and line width within an appropriate range when forming a black matrix, and can form a black matrix with excellent fine line adhesion and surface resistance value.

without

without

Claims (9)

A pigment dispersion composition for black matrix, which contains black colorant, pigment dispersant, binder resin and organic solvent. The above-mentioned pigment dispersant has a valerolactone skeleton and an isocyanurate skeleton. The pigment dispersion composition for black matrix according to claim 1, wherein the average primary particle size of the black colorant is 20 to 50 nm. The pigment dispersion composition for black matrix according to claim 1 or 2, wherein the pH value of the black colorant is 3.5 or less. The pigment dispersion composition for black matrix according to claim 1 or 2, wherein the DBP oil absorption capacity of the black colorant is 75 ml/100 g or less. The pigment dispersion composition for black matrix according to claim 1 or 2, wherein the amine value of the above-mentioned pigment dispersant is 5 to 35 mgKOH/g. The pigment dispersion composition for black matrix according to claim 1 or 2 further contains a pigment dispersion assistant, and the above-mentioned pigment dispersion assistant is a sulfonate of copper phthalocyanine. The pigment dispersion composition for black matrix according to claim 1 or 2, wherein the above-mentioned binder resin is alkali-soluble cardo resin and/or alkali-soluble epoxy (meth)acrylate resin. A photoresist composition for black matrix, which contains the pigment dispersion composition for black matrix of claim 1 or 2, a photopolymerizable compound and a photopolymerization initiator. A black matrix formed from the black matrix photoresist composition of claim 8.