Black matrix pigment dispersion composition, black matrix resist composition, and black matrix

Abstract

To provide a black matrix pigment dispersion composition which offers superior fine line adhesion when forming a black matrix, and which enables formation of a black matrix that offers a superior OD value (optical density) and low reflectance (low Y value and low L* value).SOLUTION: A black matrix pigment dispersion composition is provided, comprising a pigment, pigment dispersant, and binder resin, the pigment containing a black pigment containing a carbon black and a blue pigment, where content of the black pigment is in a range of 82-95 mass%, inclusive, with respect to the total mass of the pigment.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a pigment dispersion composition for a black matrix, a resist composition for a black matrix, and a black matrix.

Background Art

[0002] In an image display device using liquid crystal, plasma, or the like, a light-shielding film (black matrix) is provided in a gap between colored patterns in a display area of a screen, an edge of a peripheral portion of the display area, or on an outer light side of a TFT in a liquid crystal display using a TFT. And in a liquid crystal display device, mainly leakage light from a backlight, and in a plasma display device, mainly blurring due to turbidity of each color light are prevented from being reflected on the screen, which is useful for improving display characteristics (contrast and color purity).

[0003] For example, in a color filter used to convert white light of a backlight of a liquid crystal display device into colored light, usually, pixels of different hues of red, green, and blue are sequentially formed on the surface of a transparent substrate such as glass or a plastic sheet on which a black matrix is formed in a pattern such as a stripe shape or a mosaic shape.

[0004] Also, in a touch panel combining an image display device and a position input device, a color filter in which a black matrix is formed as a light-shielding film is similarly used. Conventionally, it has been generally formed on the side opposite to the sensor substrate with a cover glass interposed therebetween. However, as the demand for weight reduction of the touch panel increases, development of a technology for simultaneously forming a light-shielding film and a touch sensor on the same side of the cover glass is progressing so as to achieve more weight reduction.

[0005] As a method for forming such a black matrix, for example, a photolithography method (pigment method) using a composition for a black matrix containing a pigment is utilized. As the pigment, carbon black or the like that is mainly excellent in light-shielding properties is used. However, in a liquid crystal display device including a color filter substrate having a black matrix using a black pigment such as carbon black as a light-shielding material, deterioration of outdoor visibility due to external light reflection has been a problem.

[0006] Against this background, a black matrix with a low reflectance (low Y value, low L * value) has been demanded, and it has been difficult with a dispersion liquid for a black matrix using only a black pigment as a coloring material. Therefore, a dispersion liquid for a black matrix containing not only a black pigment but also pigments other than black as coloring materials has been studied.

[0007] For example, in Patent Document 1, there is disclosed a pigment dispersion composition for a black matrix containing at least, as a light-shielding material, (A) a black pigment and (B) a non-black pigment, and containing (C) an alkali-soluble resin, (D) a polyfunctional acrylic monomer, (E) a photo radical polymerization initiator, and (F) an organic solvent, wherein the weight ratio of the (A) black pigment to the total weight of the light-shielding material is 60% by weight or more and 95% by weight or less, and as the (A) black pigment, it contains (A-1) carbon black, and as the (B) non-black pigment, it contains (B-1) a yellow pigment and (B-2) a red pigment.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0009] Patent Document 1 discloses that a yellow pigment and a red pigment are contained as non-black pigments.

[0010] However, in recent years, a black matrix with a further lower reflectance (low Y value, low L * value) has been required, and there has been room for improvement.

[0011] In addition, in recent years, a black matrix that is excellent in fine line adhesion and also excellent in OD value (optical density) when forming a black matrix has been required.

[0012] Therefore, an object of the present invention is to provide a pigment dispersion composition for a black matrix that is excellent in fine line adhesion and OD value (optical density) when forming a black matrix and can form a black matrix with a low reflectance (low Y value, low L * value).

Means for Solving the Problems

[0013] The present invention contains a pigment, a pigment dispersant, and a binder resin. The above pigment contains a black pigment and a blue pigment. The above black pigment contains carbon black, and the content of the above black pigment is 82% by mass or more and 95% by mass or less based on the total mass of the above pigment. It is a pigment dispersion composition for a black matrix.

[0014] The pigment dispersion composition for a black matrix of the present invention preferably further contains a pigment derivative, and the above pigment derivative is preferably a sulfonated product of copper phthalocyanine. In addition, it is preferable that the above blue pigment contains at least one selected from C.I. Pigment Blue 15:6, C.I. Pigment Blue 15:3, C.I. Pigment Blue 15:4, C.I. Pigment Blue 16, and C.I. Pigment Blue 60. In addition, it is preferable that the above black pigment contains acidic carbon black. In addition, it is preferable that the above binder resin is an alkali-soluble cardo resin. Further, the present invention is also a resist composition for a black matrix containing the pigment dispersion composition for a black matrix, a photopolymerizable compound, and a photoinitiator of the present invention. Further, the present invention is also a black matrix formed from the resist composition for a black matrix of the present invention.

Effects of the Invention

[0015] The present invention is excellent in fine line adhesion when forming a black matrix, and is excellent in OD value (optical density), and can form a black matrix with a low reflectance (low Y value, low L * value). Thus, the present invention can provide a pigment dispersion composition for a black matrix.

Modes for Carrying Out the Invention

[0016] <Pigment Dispersion Composition for Black Matrix> The pigment dispersion composition for a black matrix of the present invention contains a pigment, a pigment dispersant, and a binder resin. The pigment contains a black pigment and a blue pigment. The black pigment contains carbon black, and the content of the black pigment is 82% by mass or more and 95% by mass or less based on the total mass of the pigment.

[0017] By containing a blue pigment, the pigment dispersion composition for a black matrix of the present invention has a bluer color tone and higher blackness (lower L * value) than carbon black alone, suppresses ultraviolet absorption, and thus is considered to promote internal curing and improve fine line adhesion when exposed to UV light. Also, the blue pigment is superior in OD value to being used in combination with other organic pigments, has a high affinity with carbon black, and is considered to contribute to low reflectance (low Y value) by acting as a spacer for carbon black and reflecting light. However, the present invention may not be construed as being limited to the above mechanism. Hereinafter, each component constituting the pigment dispersion composition for a black matrix of the present invention will be described in detail.

[0018] [Pigment] (Black pigment) The pigment dispersion composition for a black matrix of the present invention contains a black pigment.

[0019] The above black pigment contains carbon black. As the above carbon black, it is more preferable that it is acidic carbon black or neutral carbon black.

[0020] The above-mentioned acidic carbon black and neutral carbon black will be described. Carbon black can be roughly classified into acidic carbon black and neutral carbon black according to the surface structure. Acidic carbon black is a carbonaceous substance that originally or artificially oxidized, and shows acidity when mixed and boiled with distilled water. On the other hand, neutral carbon black is known to show neutral or higher pH when mixed and boiled with distilled water.

[0021] As the above black pigment, an average primary particle diameter of 20 to 50 nm is preferable, and an average primary particle diameter of 25 to 45 nm is more preferable. By setting the average primary particle diameter of the above black pigment within the above range, the line width of the formed black matrix can be preferably maintained, and the fine line adhesion and surface resistance value can be more preferably improved. In addition, storage stability can also be preferably imparted. Note that the above average primary particle diameter is the value of the arithmetic average diameter by electron microscope observation.

[0022] As the acidic carbon black, a pH range of 2.0 to 4.0 is preferred. Specifically, examples include Raven1080 (average primary particle size 28 nm, pH 2.4), Raven1100 (average primary particle size 32 nm, pH 2.9) manufactured by Columbian Chemicals; MA-7 (average primary particle size 24 nm, pH 2.5), MA-8 (average primary particle size 24 nm, pH 3.0), MA-100 (average primary particle size 22 nm, pH 3.5) manufactured by Mitsubishi Chemical; Special Black 250 (average primary particle size 56 nm, pH 3.0), Special Black 350 (average primary particle size 31 nm, pH 3.0), Special Black 550 (average primary particle size 25 nm, pH 4.0), NEROX305 (average primary particle size of about 28 nm, pH about 2.8), NEROX3500 (average primary particle size of about 31 nm, pH about 2.5) manufactured by Orion Engineered Carbons, etc.

[0023] As the neutral carbon black, a pH range of 8.0 to 10.0 is preferred. Specifically, examples include Printex25 (average primary particle size 56 nm, pH 9.5), Printex35 (average primary particle size 31 nm, pH 9.5), Printex65 (average primary particle size 21 nm, pH 9.5) manufactured by Orion Engineered Carbons; MA#20 (average primary particle size 40 nm, pH 8.0), MA#40 (average primary particle size 40 nm, pH 8.0), MA#30 (average primary particle size 30 nm, pH 8.0) manufactured by Mitsubishi Chemical, etc.

[0024] The above pH can be measured at 25°C using a glass electrode after preparing an aqueous suspension by adding 1 g of carbon black to 20 ml of distilled water (pH 7.0) excluding carbonic acid and mixing with a magnetic stirrer (German Industrial Standard DIN ISO 787 / 9).

[0025] Regarding the content of the above black pigment, from the viewpoints of reflectance and OD when forming a black matrix, it is 82% by mass or more and 95% by mass or less based on the total mass of the above pigment. The content of the above black pigment is preferably 82% by mass or more and 95% by mass or less, more preferably 85% by mass or more and 92% by mass or less, and most preferably 90% by mass, based on the total mass of the above pigments.

[0026] (Blue pigment) The pigment dispersion composition for a black matrix of the present invention contains a blue pigment.

[0027] Examples of the above blue pigment include C.I. Pigment Blue 1, 1:2, 9, 14, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 17, 19, 25, 27, 28, 29, 33, 35, 36, 56, 56:1, 60, 61, 61:1, 62, 63, 66, 67, 68, 71, 72, 73, 74, 75, 76, 78, 79.

[0028] From the viewpoints of dispersion stability and developability, the above blue pigment preferably contains at least one selected from C.I. Pigment Blue 15:6, C.I. Pigment Blue 15:3, C.I. Pigment Blue 15:4, C.I. Pigment Blue 16, and C.I. Pigment Blue 60.

[0029] The content of the above blue pigment is preferably 5% by mass or more and 18% by mass or less, more preferably 5% by mass or more and 15% by mass or less, still more preferably 12% by mass or less, and most preferably 10% by mass, based on the total mass of the above pigments, from the viewpoints of low reflectance (low Y value, low L * value) property and OD when forming a black matrix.

[0030] (Others) From the viewpoint of low reflectance (low Y value, low L * value) property, the above pigment preferably does not contain pigments other than the above-described black pigment and blue pigment (consisting of a black pigment and a blue pigment).

[0031] (Content of pigment) As the content of the above pigment, from the viewpoints of light shielding properties when forming a black matrix and pigment dispersibility, the mass fraction with respect to the total solid content of the pigment dispersion composition for a black matrix of the present invention is preferably 5 to 85% by mass, more preferably 10 to 80% by mass.

[0032] (Pigment dispersant) The pigment dispersion composition for a black matrix of the present invention contains a pigment dispersant.

[0033] The above pigment dispersant preferably has an amine value of 10 to 200 mgKOH / g. When the amine value of the above pigment dispersant is within the above range, the viscosity of the pigment dispersion composition for a black matrix can be reduced, and the carbon black in the coating film can be made highly concentrated. Therefore, a black matrix excellent in optical density can be obtained.

[0034] The above pigment dispersant more preferably has an amine value of 20 to 150 mgKOH / g. The amine value indicates the total amount of free base and base, and is expressed as the number of milligrams of potassium hydroxide equivalent to the hydrochloric acid required to neutralize 1 g of the sample.

[0035] The above pigment dispersant is a basic group-containing pigment dispersant, and an anionic surfactant, a basic group-containing polyester-based pigment dispersant, a basic group-containing acrylic-based pigment dispersant, a basic group-containing urethane-based pigment dispersant, a basic group-containing carbodiimide-based pigment dispersant, etc. can be used. These basic group-containing pigment dispersants may be used alone or in combination of two or more. Among them, a basic group-containing polymer pigment dispersant is preferable from the viewpoint of obtaining good pigment dispersibility.

[0036] Specific examples of the above basic group-containing polymer pigment dispersant include (1) A reaction product of an amino group and / or an imino group of a polyamine compound (e.g., poly(alkyleneamine) such as polyallylamine, polyvinylamine, polyethylene polyimine, etc.) and at least one selected from the group consisting of polyesters, polyamides, and polyester amides having a free carboxyl group (Japanese Patent Laid-Open No. 2001-59906), (2) A reaction product of a low molecular weight amino compound such as poly(lower)alkyleneimine or methyliminobispropylamine and a polyester having a free carboxyl group (Japanese Patent Laid-Open No. 54-37082, Japanese Patent Laid-Open No. 01-311177), (3) A reaction product obtained by sequentially reacting an isocyanate group of a polyisocyanate compound with alcohols such as methoxypolyethylene glycol, polyesters having one hydroxyl group such as caprolactone polyester, compounds having 2 to 3 isocyanate group-reactive functional groups, and aliphatic or heterocyclic hydrocarbon compounds having an isocyanate group-reactive functional group and a tertiary amino group (Japanese Patent Laid-Open No. 02-612), (4) A compound obtained by reacting a polymer of an acrylate having an alcoholic hydroxyl group with a polyisocyanate compound and a hydrocarbon compound having an amino group, (5) A reaction product obtained by adding a polyether chain to a low molecular weight amino compound, (6) A reaction product obtained by reacting a compound having an isocyanate group with a compound having an amino group (Japanese Patent Laid-Open No. 04-210220), (7) A reaction product obtained by reacting a polyepoxy compound with a linear polymer having a free carboxyl group and an organic amine compound having one secondary amino group (Japanese Patent Laid-Open No. 09-87537), (8) A reaction product of a polycarbonate compound having a functional group capable of reacting with an amino group at one end and a polyamine compound (Japanese Patent Laid-Open No. 09-194585), (9) At least one selected from methacrylic acid esters or acrylic acid esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, stearyl methacrylate, benzyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, stearyl acrylate, benzyl acrylate, etc., at least one basic group-containing polymerizable monomer such as acrylamide, methacrylamide, N-methylolamide, vinyl imidazole, vinyl pyridine, a monomer having an amino group and a polycaprolactone skeleton, and at least one of styrene, styrene derivatives, and other polymerizable monomers (Japanese Patent Laid-Open No. 01-164429), (10) Basic group-containing carbodiimide-based pigment dispersant (WO2004 / 000950), (11) A block copolymer composed of a block having a basic group such as a tertiary amino group or a quaternary ammonium base and a block having no functional group (see the description in Japanese Patent Laid-Open No. 2005-55814), (12) A pigment dispersant obtained by subjecting polyallylamine to a Michael addition reaction with a polycarbonate compound (Japanese Patent Laid-Open No. 09-194585), (13) A carbodiimide-based compound having at least one polybutadiene chain and at least one basic nitrogen-containing group (Japanese Patent Laid-Open No. 2006-257243), (14) A carbodiimide-based compound having at least one side chain having an amide group in the molecule and at least one basic nitrogen-containing group (Japanese Patent Laid-Open No. 2006-176657), (15) A polyurethane-based compound having a structural unit having an ethylene oxide chain and a propylene oxide chain and having an amino group quaternized by a quaternizing agent (Japanese Patent Laid-Open No. 2009-175613), A compound obtained by reacting an isocyanate group of an isocyanate compound having an isocyanurate ring in the molecule with an active hydrogen group of a compound having an active hydrogen group in the molecule and having a carbazole ring and / or an azobenzene skeleton, wherein the number of carbazole rings and azobenzene skeletons in the molecule of the compound is 15 to 85% based on the total of the isocyanate group derived from the isocyanate compound having an isocyanurate ring, urethane bonds and urea bonds formed by the reaction of the isocyanate group with the active hydrogen group (Japanese Patent Laid-Open No. 2010-107965). (17) Examples include a graft copolymer obtained by introducing a polyether or polyester side chain into an acrylate polymer having an amino group.

[0037] Among the above pigment dispersants, from the viewpoints of dispersion stability, developability, and reflectance, a block copolymer composed of a block having a basic group such as a tertiary amino group or a quaternary ammonium base and a block having no functional group is preferable.

[0038] Specifically, as the above block copolymer, it is preferably composed of an A block having at least one of a quaternary ammonium base and an amino group in the side chain and a B block having no quaternary ammonium base and amino group, and it is more preferably at least one of an A-B block copolymer and a B-A-B block copolymer.

[0039] The amine value of the above block copolymer is preferably 10 to 200 mgKOH / g, and more preferably 20 to 150 mgKOH / g. Note that the amine value is a value expressed by the mg number of KOH corresponding to the molar equivalent of an acid required to neutralize the amino groups in 1 g of the acrylic block copolymer.

[0040] The molecular weight of the above block copolymer preferably has a weight average molecular weight (Mw) in terms of polystyrene measured by GPC of 1000 to 40000, and more preferably 2000 to 20000.

[0041] Examples of commercially available products of the above pigment dispersants include BYK-LPN21116, BYK-2000, BYK-LPN6919, BYK-LPN21324, BYK-LPN22102 (all manufactured by BYK Chemie Co., Ltd.), and the like.

[0042] The content of the above pigment dispersant is preferably 1 to 200 parts by mass, more preferably 5 to 100 parts by mass, based on 100 parts by mass of the above black pigment.

[0043] (Binder resin) The pigment dispersion composition for a black matrix of the present invention contains a binder resin.

[0044] Examples of the above binder resin include thermosetting resins, thermoplastic resins, photopolymerizable compounds, alkali-soluble resins, and the like. These can be used alone or in admixture of two or more.

[0045] Examples of the above thermosetting resin and thermoplastic resin include, for example, butyral resin, styrene-maleic acid copolymer, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyurethane resin, phenol resin, polyester resin, acrylic resin, alkyd resin, styrene resin, polyamide resin, rubber resin, cyclized rubber, epoxy resin, celluloses, polybutadiene, polyimide resin, benzoguanamine resin, melamine resin, urea resin, card resin, and the like.

[0046] Examples of the above photopolymerizable compound include monomers having one or more photopolymerizable unsaturated bonds in the molecule, oligomers having photopolymerizable unsaturated bonds, and the like.

[0047] As the monomer having one photopolymerizable unsaturated bond in the molecule, for example, alkyl methacrylates or acrylates such as methyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, methyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, aralkyl methacrylates or acrylates such as benzyl methacrylate, benzyl acrylate, alkoxyalkyl methacrylates or acrylates such as butoxyethyl methacrylate, butoxyethyl acrylate, aminoalkyl methacrylates or acrylates such as N,N-dimethylaminoethyl methacrylate, N,N-dimethylaminoethyl acrylate, methacrylic acid esters or acrylic acid esters of polyalkylene glycol monoalkyl ethers such as diethylene glycol monoethyl ether, triethylene glycol monobutyl ether, dipropylene glycol monomethyl ether, methacrylic acid esters or acrylic acid esters of polyalkylene glycol monoaryl ethers such as hexaethylene glycol monophenyl ether, isobornyl methacrylate or acrylate, glycerol methacrylate or acrylate, 2-hydroxyethyl methacrylate or acrylate, etc. can be used.

[0048] As the monomer having two or more photopolymerizable unsaturated bonds in the molecule, for example, bisphenol A dimethacrylate, 1,4-butanediol dimethacrylate, 1,3-butylene glycol dimethacrylate, diethylene glycol dimethacrylate, glycerol dimethacrylate, neopentyl glycol dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol tetramethacrylate, dipentaerythritol hexamethacrylate, dipentaerythritol pentamethacrylate, epoxy methacrylate, bisphenol A diacrylate, 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, diethylene glycol diacrylate, glycerol diacrylate, neopentyl glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, tetraethylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol hexacrylate, dipentaerythritol pentacrylate, epoxy acrylate, etc. can be used.

[0049] As the oligomer having the photopolymerizable unsaturated bond, those obtained by appropriately polymerizing the above monomers can be used. The above binder resin can be used alone or in combination of two or more.

[0050] The above alkali-soluble resin will be described later.

[0051] When forming the black matrix, the above binder resin is preferably an alkali-soluble cardo resin from the viewpoints of dispersion stability and developability. In this specification, the above-mentioned cardo resin means a resin having a skeletal structure in which two aromatic rings are bonded to carbon atoms in the ring.

[0052] Examples of the above-mentioned cardo resin include epoxy (meth) acrylate acid adducts having a fluorene skeleton, which are addition products of a fluorene epoxy (meth) acrylic acid derivative and a dicarboxylic acid anhydride and / or a tetracarboxylic dianhydride. In this specification, "(meth)acryl" means acrylic and / or methacrylic, and "(meth)acrylate" means acrylate and / or methacrylate.

[0053] From the viewpoints of pigment dispersibility and fine line adhesion, the acid value of the above-mentioned cardo resin is preferably 5 to 300 mgKOH / g, more preferably 5 to 250 mgKOH / g, still more preferably 10 to 200 mgKOH / g, and particularly preferably 60 to 150 mgKOH / g. In this specification, the above-mentioned acid value is the theoretical acid value, which is a value obtained arithmetically based on the ethylenically unsaturated monomer having a carboxyl group and its content.

[0054] The weight average molecular weight (Mw) of the above-mentioned cardo resin is preferably 1,000 to 100,000, more preferably 1,500 to 50,000, and still more preferably 2,000 to 30,000. In this specification, as the apparatus for measuring the above-mentioned weight average molecular weight, Water2690 (manufactured by Waters) is used, and as the column, PLgel 5μm MIXED-D (manufactured by Agilent Technologies) is used.

[0055] Examples of commercially available products of the above-mentioned cardo resin include WR-301 (manufactured by ADEKA), etc.

[0056] The content of the above-mentioned binder resin is preferably 3 to 50% by mass based on the total solid content of the pigment dispersion composition for a black matrix of the present invention.

[0057] (Pigment derivative) The pigment dispersion composition for a black matrix of the present invention preferably further contains a pigment derivative.

[0058] Examples of the above-mentioned pigment derivative include at least one selected from the group consisting of an acid group-containing pigment derivative and an acid group-containing dye derivative.

[0059] Examples of the above-mentioned acid group-containing pigment derivative and acid group-containing dye derivative include phthalocyanine-based pigment derivatives which are sulfonated products of copper phthalocyanine, anthraquinone-based pigment derivatives having an acid group, naphthalene-based pigment derivatives having an acid group, pigment derivatives having a diketopyrrolopyrrole skeleton, and the like. Among these, a sulfonated product of copper phthalocyanine is preferable from the viewpoint that it has a high affinity with the conjugated double bond of the above-mentioned black pigment and can suitably impart dispersibility.

[0060] Specific examples of the above-mentioned sulfonated product of copper phthalocyanine include Solsperse 5000S manufactured by Lubrizol Corporation, Solsperse 12000S, BYK-SYNERGIST 2100 manufactured by BYK-Chemie, and the like.

[0061] The content of the above-mentioned pigment derivative is preferably 0 to 20 parts by mass, more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the above-mentioned black pigment.

[0062] (Organic solvent) The pigment dispersion composition for a black matrix of the present invention preferably contains an organic solvent. As the above-mentioned organic solvent, an organic solvent conventionally used in the field of resists for liquid crystal black matrices can be preferably used.

[0063] Specific examples of the organic solvent include ether-based organic solvents such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, and diethylene glycol methyl ethyl ether; ether ester-based organic solvents such as ethylene 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 methyl isobutyl ketone, cyclohexanone, 2-heptanone, and δ-butyrolactone; ester-based organic solvents such as methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl 3-methyl-3-methoxybutylpropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, and n-amyl formate; alcohol-based solvents such as methanol, ethanol, isopropyl alcohol, and butanol; and nitrogen-containing organic solvents such as N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide. These can be used alone or in admixture of two or more thereof.

[0064] Among the above-mentioned organic solvents, in terms of solubility, dispersibility, coatability, etc., diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, cyclohexanone, 2-heptanone, ethyl 2-hydroxypropionate, 3-methyl-3-methoxybutyl propionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, n-amyl formate, etc. are preferable, and propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate are more preferable.

[0065] (Method for producing pigment dispersion composition for black matrix) The method for producing the pigment dispersion composition for a black matrix of the present invention is not particularly limited. For example, it can be produced by mixing and kneading a black pigment, a blue pigment, a pigment dispersant, a binder resin, and, if necessary, a pigment derivative and an organic solvent.

[0066] As the above-mentioned black pigment, blue pigment, pigment dispersant, binder resin, and, if necessary, pigment derivative and organic solvent, the above-mentioned materials can be used.

[0067] As the method for the above mixing and kneading, the above-mentioned various components may be added and mixed and kneaded. The method for the above kneading is not particularly limited. For example, a bead mill, a ready mill, an ultrasonic homogenizer, a high-pressure homogenizer, a paint shaker, a ball mill, a roll mill, a sand mill, a sand grinder, a dyno mill, a dispermat, an SC mill, a nanomizer, etc. can be used, and they may be mixed and kneaded by a known method.

[0068] <Resist composition for black matrix> The present invention is also a resist composition for a black matrix obtained from the pigment dispersion composition for a black matrix of the present invention.

[0069] (Pigment dispersion composition for black matrix) The resist composition for black matrix of the present invention contains the above-described pigment dispersion composition for black matrix of the present invention. As the content of the above pigment dispersion composition for black matrix, based on the total mass of the resist composition for black matrix of the present invention, it is preferably 30 to 80% by mass, and more preferably 40 to 75% by mass.

[0070] (Photoinitiator) The resist composition for black matrix of the present invention preferably contains a photoinitiator. The above photoinitiator is not particularly limited as long as it can generate radicals or cations by irradiation with active energy rays such as ultraviolet rays or electron beams. For example, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(O-acyloxime)ethanone, benzophenone, N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 2,2-diethoxyacetophenone, benzoin, benzoin methyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, α-hydroxyisobutyl phenyl ketone, thioxanthone, 2-chlorothioxanthone, 1-hydroxycyclohexyl phenyl ketone, t-butyl anthraquinone, 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-morpholinopropan-1-one and other benzophenone-based, thioxanthone-based, anthraquinone-based, triazine-based photoinitiators and the like can be mentioned. The above photoinitiator is used alone or in combination of two or more.

[0071] The content of the above photoinitiator is preferably 1 to 20% by mass based on the total solid content of the resist composition for a black matrix of the present invention.

[0072] (Photopolymerizable compound) The resist composition for a black matrix of the present invention preferably contains a photopolymerizable compound. As the above photopolymerizable compound, those described in the above pigment dispersion composition for a black matrix can be appropriately selected and used.

[0073] The content of the above photopolymerizable compound is preferably 0.1 to 50% by mass based on the total solid content of the resist composition for a black matrix of the present invention.

[0074] (Alkali-soluble resin) The resist composition for a black matrix of the present invention preferably contains an alkali-soluble resin. As the above alkali-soluble resin, it is preferably one that acts as a binder for the above black pigment and is soluble in a developing solution used in the developing process for producing a black matrix, particularly an alkali developing solution.

[0075] The above alkali-soluble resin may be a block copolymer. By adopting a block copolymer, the pigment dispersibility can be improved and the solubility in PGMEA and an alkali developing solution can be imparted compared to other copolymers. Among those block copolymers, a block copolymer having a block composed of an ethylenically unsaturated monomer having one or more carboxyl groups and a block composed of other copolymerizable ethylenically unsaturated monomers is preferable.

[0076] The block copolymer is not particularly limited, and those conventionally used can be used. Among them, specifically, ethylenically unsaturated monomers having a carboxyl group such as acrylic acid and methacrylic acid, and styrene copolymerizable with an ethylenically unsaturated monomer having a carboxyl group, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, allyl acrylate, allyl methacrylate, benzyl acrylate, benzyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, glycerol monoacrylate, glycerol methacrylate, N-phenylmaleimide, polystyrene macromonomer, polymethyl methacrylate macromonomer, monomers such as carboxyepoxy diacrylate, and at least one ethylenically unsaturated monomer selected from the group of oligomers can be mentioned. However, it is desirable not to use N-vinylpyrrolidone and sulfur element-containing monomers. As the block copolymer, a block resin synthesized by living radical polymerization or anionic polymerization can be employed. Some block portions of the block copolymer may be composed of a random copolymer.

[0077] As the alkali-soluble resin, a cardo resin is preferable. As the cardo resin, those described in the above-mentioned pigment dispersion composition for a black matrix can be preferably used.

[0078] The acid value of the alkali-soluble resin is preferably 5 to 300 mgKOH / g, more preferably 5 to 250 mgKOH / g, still more preferably 10 to 200 mgKOH / g, and particularly preferably 60 to 150 mgKOH / g from the viewpoint of fine line adhesion.

[0079] The weight average molecular weight of the alkali-soluble resin is preferably 1,000 to 100,000, more preferably 1,500 to 50,000, and still more preferably 2,000 to 30,000 from the viewpoints of fine line adhesion and solubility in organic solvents.

[0080] The content of the above alkali-soluble resin is preferably 1 to 200 parts by mass, more preferably 10 to 150 parts by mass, based on 100 parts by mass of the above black pigment. In this case, if the content of the above alkali-soluble resin is less than 1 part by mass, the adhesion of fine lines may decrease. If the content of the above alkali-soluble resin exceeds 200 parts by mass, the concentration of the above black pigment will relatively decrease, making it difficult to achieve the target color density as a thin film in some cases.

[0081] The above alkali-soluble resin preferably contains neither primary, secondary, nor tertiary amino groups, and further preferably does not contain a quaternary ammonium group. More preferably, it has no basic group. Note that an alkali-soluble resin having a structure other than the block copolymer may be blended as long as the effects of the present invention are not impaired.

[0082] (Organic solvent) As the above organic solvent, the organic solvents described in the above pigment dispersion composition for black matrix can be appropriately selected and used.

[0083] The content of the above organic solvent is preferably 1 to 40% by mass, more preferably 5 to 35% by mass, based on the total mass of the resist composition for black matrix of the present invention.

[0084] (Other additives) The resist composition for black matrix of the present invention can appropriately use various additives such as a thermal polymerization inhibitor, an ultraviolet absorber, an antioxidant, and a leveling agent, if necessary.

[0085] (Manufacturing method of the resist composition for black matrix) As a manufacturing method of the resist 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 stirred and mixed using a stirrer or the like to prepare it. The method of stirring and mixing is not particularly limited, and known methods such as ultrasonic dispersers, high-pressure emulsifiers, bead mills, three-roll mills, sand mills, kneaders, etc. can be used. Also, filtration may be performed with a filter after the above stirring and mixing.

[0086] <Black matrix> The black matrix of the present invention is formed from the resist composition for black matrix of the present invention.

[0087] The method for forming the black matrix of the present invention is not particularly limited. For example, the resist composition for black matrix of the present invention is applied onto a transparent substrate and dried to form a coating film. Then, a photomask is placed on the coating film, and an image is exposed, developed, and, if necessary, a black matrix can be formed by a method such as photocuring through the photomask.

[0088] For the method of applying, drying, exposing, and developing the resist composition for black matrix of the present invention, known methods can be appropriately selected. Also, as the above transparent substrate, a known transparent substrate such as a glass substrate or a plastic substrate can be appropriately selected and used.

[0089] 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 as the film thickness after drying. By setting the thickness within the above range, a predetermined pattern can be preferably developed, and a predetermined optical density can be preferably imparted.

[0090] The black matrix of the present invention is excellent in fine line adhesion. Specifically, if the fine line adhesion measured by the following method is 6 μm or less, it can be determined that the fine line adhesion is excellent.

[0091] The above fine line adhesion is measured by the following method. The prepared resist composition for a black matrix is applied onto a glass substrate (Corning 1737, manufactured by Corning Inc.) using a spin coater to a film thickness of 1 μm, and prebaked at 100°C for 2 minutes. Next, using a photomask having line patterns of 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 12 μm, 14 μm, 16 μm, 18 μm, 20 μm, and 30 μm, exposure is carried out using a high-pressure mercury lamp with a UV integrated light amount of 80 mJ / cm 2 . In a 0.05% aqueous potassium hydroxide solution at 23°C, development is started from the time (break time) when a development pattern begins to appear by shower development at 1.0 kgf / cm 2 , and development is terminated when the time reaches twice the development start time (break time). After development is completed, spray water washing is carried out at a pressure of 1.0 kgf / cm 2 . The width (μm) of the smallest line pattern remaining on the glass substrate is evaluated.

[0092] The black matrix of the present invention is excellent in optical density (OD value). Specifically, if the OD value is 2.80 or more, it can be determined that the optical density (OD value) is excellent. The above OD value is preferably 2.85 or more, and more preferably 2.90 or more.

[0093] The above optical density (OD value) is measured by the following method. The prepared resist composition for a black matrix is applied onto a glass substrate (Corning 1737, manufactured by Corning Inc.) using a spin coater to a film thickness of 1 μm, and prebaked at 100°C for 2 minutes. Next, exposure is carried out with a high-pressure mercury lamp (UV integrated light amount 80 mJ / cm 2 ), and further post-baking is carried out at 230°C for 30 minutes followed by 250°C for 150 minutes to produce a black resist pattern (black matrix) formed only in the solid part. The optical density of the produced black resist pattern (film thickness: 1 μm) is measured using a transmission - type black density meter (D200 - II, manufactured by Gretag Macbeth).

[0094] The black matrix of the present invention has a low reflectance (low Y - value and low L * - value). If the above - mentioned Y - value is 5.80 or less and the above - mentioned L * - value is 29.00 or less, it can be determined that the reflectance is sufficiently low.

[0095] The above - mentioned Y - value is preferably 5.80 or less, and more preferably 5.70 or less. Also, the above - mentioned L * - value is preferably 29.00 or less, and more preferably 28.50 or less.

[0096] The above - mentioned Y - value and L * - value can be measured by the following method. The resist composition for the produced black matrix is applied onto a glass substrate (Corning 1737, manufactured by Corning) using a spin coater so that the film thickness becomes 1 μm, and pre - baked at 100 °C for 2 minutes to produce a coating film of only the solid part. Using a spectrophotometer (CM - 26d, manufactured by Konica Minolta), the L * - value of the glass surface is measured, and the Y - value is calculated from the average value of the measured reflectance values obtained under the conditions of a wavelength of 360 - 740 nm.

[0097] The following matters are disclosed in this specification.

[0098] The present disclosure (1) is a pigment - dispersion composition for a black matrix, which contains a pigment, a pigment dispersant, and a binder resin. The above - mentioned pigment contains a black pigment and a blue pigment. The above - mentioned black pigment contains carbon black, and the content of the above - mentioned black pigment is 82% by mass or more and 95% by mass or less based on the total mass of the above - mentioned pigment. The present disclosure (2) further contains a pigment derivative, and the pigment derivative is the pigment dispersion composition for a black matrix described in the present disclosure (1), which is a sulfonated product of copper phthalocyanine. The present disclosure (3) is the pigment dispersion composition for a black matrix described in the present disclosure (1) or (2), wherein the blue pigment contains at least one selected from C.I. Pigment Blue 15:6, C.I. Pigment Blue 15:3, C.I. Pigment Blue 15:4, C.I. Pigment Blue 16, and C.I. Pigment Blue 60. The present disclosure (4) is the pigment dispersion composition for a black matrix according to any one of the present disclosures (1) to (3), wherein the black pigment contains acidic carbon black. The present disclosure (5) is the pigment dispersion composition for a black matrix according to any one of the present disclosures (1) to (4), wherein the binder resin is an alkali-soluble cardo resin. The present disclosure (6) is a resist composition for a black matrix containing the pigment dispersion composition for a black matrix according to any one of the present disclosures (1) to (5), a photopolymerizable compound, and a photoinitiator. The present disclosure (7) is also a black matrix formed from the resist composition for a black matrix according to the present disclosures (1) to (6).

Examples

[0099] 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 application scope thereof. Unless otherwise specified, in this example, "parts" and "%" represent "parts by mass" and "mass%", respectively.

[0100] The various materials used in the following examples and comparative examples are as follows.

[0101] <Black pigment> Acidic carbon black (NEROX3500, average primary particle diameter 31 nm, pH 2.5, product name: "NEROX3500", manufactured by Orion Engineered Carbons Co., Ltd.) <Blue pigment> C.I. Pigment Blue 15:6 (PB15:6) C.I. Pigment Blue 15:3 (PB15:3) C.I. Pigment Blue 15:4 (PB15:4) C.I. Pigment Blue 16 (PB16) C.I. Pigment Blue 60 (PB60) <Pigment Dispersant> LPN6919 (Block copolymer composed of a block having a basic group such as a tertiary amino group and a quaternary ammonium base and a block having no functional group, product name: "BYK-LPN6919", manufactured by BYK-Chemie) <Pigment Derivative> BYK2100 (Sulfonated copper phthalocyanine, product name: "BYK-SYNERGIST2100", manufactured by BYK-Chemie) <Binder Resin> WR-301 (Product name "WR-301", cardo resin, acid value 100 mgKOH / g, solid content 45% by mass, manufactured by ADEKA) <Organic Solvent> PGMEA (Propylene Glycol Monomethyl Ether Acetate) <Photoinitiator> OXE02 (Product name "Irgacure OXE02", 1-[9-Ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(O-acetoxime)ethanone, manufactured by BASF) <Photopolymerizable Compound> DPHA (Dipentaerythritol 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) <Levelling Agent> Megafac F-554 (Manufactured by DIC)

[0102] <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 24 hours to prepare a pigment dispersion composition for a black matrix.

[0103]

Table 1

[0104] <Black matrix resist composition> Using a high-speed stirrer, the above pigment dispersion composition for a black matrix and other materials (photoinitiator, photopolymerizable compound, alkali-soluble resin, and organic solvent) were uniformly mixed so as to have the composition shown in Table 2. Thereafter, filtration was performed using a filter with a pore size of 3 μm to prepare resist compositions for a black matrix of Examples and Comparative Examples. In Table 2, the numerical values in the right column of each material of the photoinitiator, photopolymerizable compound, alkali-soluble resin, and organic solvent represent the blending amounts.

[0105] <Evaluation test> (Fine line adhesion) The prepared resist composition for a black matrix was applied onto a glass substrate (Corning 1737, manufactured by Corning) using a spin coater so as to have a film thickness of 1 μm, and pre-baked at 100 °C for 2 minutes. Next, using a photomask having line patterns of 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 12 μm, 14 μm, 16 μm, 18 μm, 20 μm, and 30 μm, exposure was performed using a high-pressure mercury lamp with a UV integrated light amount of 80 mJ / cm 2 2. In a 0.05% aqueous potassium hydroxide solution at 23 °C, development was started from the time (break time) when the development pattern began to appear by shower development at 1.0 kgf / cm 2 2, and development was terminated when the time reached twice the development start time (break time) of 0. After the completion of development, spray water washing was performed at a pressure of 1.0 kgf / cm 2 2. The width (μm) of the smallest line pattern remaining on the above glass substrate was evaluated. The results are shown in Table 2.

[0106] (Optical density) The prepared resist composition for black matrix was applied onto a glass substrate (Corning 1737, manufactured by Corning Inc.) using a spin coater to a film thickness of 1 μm, and pre-baked at 100 °C for 2 minutes. Subsequently, it was exposed using a high-pressure mercury lamp (UV integrated light amount: 80 mJ / cm 2 ), and post-baked at 230 °C for 30 minutes to fabricate a black resist pattern (black matrix) formed only in the solid portions. The optical density of the fabricated black resist pattern (film thickness: 1 μm) was measured using a transmission type black density meter (manufactured by GretagMacbeth; D200-II). The results are shown in Table 2.

[0107] (Y value and L * value) The prepared resist composition for black matrix was applied onto a glass substrate (Corning 1737, manufactured by Corning Inc.) using a spin coater to a film thickness of 1 μm, and pre-baked at 100 °C for 2 minutes to fabricate a solid-only coating film. Using a spectrophotometer (CM-26d, manufactured by Konica Minolta Inc.), the L * value of the glass surface was measured, and the Y value was calculated from the average value of the measured reflectance values obtained under the conditions of wavelengths from 360 to 740 nm. The results are shown in Table 2.

[0108]

Table 2

[0109] From Table 2, in the examples using the pigment dispersion composition for black matrix of the present invention, when forming the black matrix, it has excellent fine line adhesion, and also has excellent OD value (optical density), and it was confirmed that a black matrix with low reflectance (low Y value and low L * value) can be formed.

Industrial Applicability

[0110] The pigment dispersion composition for a black matrix, the resist composition for a black matrix, and the black matrix of the present invention can be suitably used as a black matrix for an image display device, a touch panel, or the like.

Claims

1. A pigment dispersion composition for a black matrix, comprising a pigment, a pigment dispersant, and a binder resin, wherein the pigment contains a black pigment and a blue pigment, the black pigment contains carbon black, and the content of the black pigment is 82% by mass or more and 95% by mass or less based on the total mass of the pigment. A pigment dispersion composition for a black matrix.

2. The pigment dispersion composition for a black matrix according to claim 1, further comprising a pigment derivative, wherein the pigment derivative is a sulfonated product of copper phthalocyanine.

3. The pigment dispersion composition for a black matrix according to claim 1 or 2, wherein the blue pigment contains at least one selected from C.I. Pigment Blue 15:6, C.I. Pigment Blue 15:3, C.I. Pigment Blue 15:4, C.I. Pigment Blue 16, and C.I. Pigment Blue 60.

4. The pigment dispersion composition for a black matrix according to claim 1 or 2, wherein the black pigment contains acidic carbon black.

5. The pigment dispersion composition for a black matrix according to claim 1 or 2, wherein the binder resin is an alkali-soluble cardo resin.

6. A resist composition for a black matrix, comprising the pigment dispersion composition for a black matrix according to claim 1 or 2, a photopolymerizable compound, and a photoinitiator.

7. A black matrix formed from the resist composition for a black matrix according to claim 6.

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