Black matrix coloring composition and color filter

Abstract

Technical problem: To provide a coloring composition for a black matrix having high dispersion performance of a coloring material and a small amount of formaldehyde generation over time. Solution: A coloring composition for a black matrix, characterized in that the coloring composition for a black matrix contains a coloring material, a dispersant, a dispersion medium, and a phosphite, and the phosphite is a compound represented by the general formula (5): In the general formula (5), R 51 represents an alkyl group having 1 to 20 carbon atoms, R 52 and R 53 each independently represent a hydrocarbon group, R 52 and R 53 may also be bonded to each other to form a cyclic structure, and the compound represented by the general formula (5) may also form a dimer or a trimer by bonding through R 52 or R 53 .

Description

Technical Field

[0001] The present invention relates to a coloring composition for a black matrix. Background Art

[0002] A color filter for an image display device such as a liquid crystal display includes color pixels formed on a transparent substrate that transmit light of the three primary colors of red (R), green (G), and blue (B), and a black matrix formed at the boundaries of the respective color pixels and substantially not transmitting visible light as black.

[0003] In the manufacture of a liquid crystal display, a transparent electrode for driving liquid crystal is formed on the color filter by evaporation or sputtering, and an alignment film for aligning the liquid crystal in a certain direction is formed thereon. In order to fully obtain the performance of these transparent electrodes and alignment films, the formation of these transparent electrodes and alignment films needs to be carried out at a high temperature of 200°C or higher. Therefore, as a method of imparting a coloring material to the transparent substrate of the color filter, a pigment dispersion method using a pigment excellent in heat resistance and light resistance as the coloring material is widely used.

[0004] In the above pigment dispersion method, a coloring composition in which a pigment, a dispersant, a binder resin, and a dispersion medium (solvent) are dispersed is used. When forming a colored layer, first, the coloring composition is coated on a transparent substrate to form a coating film formed of the coloring composition on the transparent substrate. Then, via a photomask having a desired pattern shape, radiation (hereinafter referred to as "exposure") is irradiated to cure the binder resin. Finally, the unexposed portion is removed by development to form a colored layer having a desired pattern shape. In addition, a treatment such as heating can be performed on the colored layer as needed. In this way, a color filter can be prepared by forming a black pattern (hereinafter referred to as "black matrix") and color pixels of red (R), green (G), and blue (B).

[0005] The black matrix is formed in a lattice shape or a strip shape, and is a thin film and a fine part, and requires sharp edges and high linearity. In recent years, a coloring composition using carbon black as a light-shielding material has been used in the formation of the black matrix. In order to maintain high light-shielding properties in a thin film, it is necessary to increase the carbon black content concentration. When carbon black is dispersed in the coloring composition, with the increase in the surface area of carbon black, re-aggregation easily occurs, and the problem of decreased dispersion stability appears.

[0006] In order to solve this problem, a method of improving the affinity between the dispersion medium and carbon black in the coloring composition has been proposed, and various dispersants have been investigated as its solutions. For example, the following compositions have been proposed: a coloring composition using a polyurethane-based dispersant (Reference Patent Document 1), a coloring composition using a polyurethane-based dispersant having a basic functional group (Reference Patent Document 2), and a coloring composition using a dispersant composed of a polyester or polyether having a basic functional group (Reference Patent Document 3).

[0007] Prior art documents

[0008] Patent documents

[0009] Patent document 1: Japanese Patent Laid-Open No. 2000-227654

[0010] Patent document 2: Japanese Patent Laid-Open No. 2009-175613

[0011] Patent document 3: Japanese Patent Laid-Open No. 10-82908 Summary of the invention

[0012] Technical problem to be solved by the invention

[0013] In recent years, environmental standards have become increasingly strict, and there has been a problem of formaldehyde generation over time in the black matrix due to the coloring composition. For conventional coloring compositions such as Patent Documents 1 to 3, the amount of formaldehyde in the coloring composition no longer meets the environmental standards.

[0014] In view of the above circumstances, the present invention is made, and its object is to provide a coloring composition for a black matrix having high dispersibility of a coloring material and a small amount of formaldehyde generation over time.

[0015] Solution for solving the technical problem

[0016] The coloring composition for a black matrix of the present invention that can solve the above problems is characterized in that it contains a coloring material, a dispersant, a dispersion medium, and a phosphite, and the phosphite is a compound represented by the general formula (5).

[0017]

[0018] In the general formula (5), R 51 represents an alkyl group having 1 to 20 carbon atoms, R 52 and R 53 each independently represent a hydrocarbon group, R 52 and R 53 may also be bonded to each other to form a cyclic structure, and the compound represented by the general formula (5) may also be bonded through R 52 or R 53 to form a dimer or a trimer.

[0019] By making the phosphite represented by the general formula (5) coexist in the coloring composition, formaldehyde generated from the complexing agent undergoes an irreversible reaction with the phosphite, thereby reducing the formaldehyde in the coloring composition.

[0020] Advantages of the invention

[0021] According to the present invention, a coloring composition for a black matrix with high dispersion performance of a coloring material and a small amount of formaldehyde generation over time can be obtained. Detailed Embodiments

[0022] Hereinafter, an example of a preferred embodiment of the present invention will be described. However, the following embodiments are merely examples. The present invention is not limited by any of the following embodiments. In the present invention, “(meth)acrylic acid” means “at least one of acrylic acid and methacrylic acid”. “(meth)acrylate” means “at least one of acrylate and methacrylate”.

[0023] <Coloring Composition for Black Matrix>

[0024] The coloring composition for a black matrix of the present invention (hereinafter, sometimes simply referred to as “coloring composition”) is characterized in that it contains a coloring material, a dispersant, a dispersion medium, and a phosphite, and the phosphite is a compound represented by the general formula (5).

[0025] In the conventional coloring composition, formaldehyde is generated over time due to the compounding agents in the coloring composition. Here, by allowing the phosphite represented by the general formula (5) to coexist, the formaldehyde generated from the compounding agents undergoes an irreversible reaction with the phosphite. Therefore, the formaldehyde in the coloring composition can be reduced.

[0026] Preferably, the coloring composition for a black matrix substantially does not transmit visible light. Specifically, the optical density (OD value) of the black resist pattern formed from the coloring composition is preferably 0.5 or more, more preferably 1.0 or more, and still more preferably 1.5 or more. The optical density is measured by spin-coating the coloring composition on a glass substrate with a film thickness of 1 μm, forming only a solid portion of the black resist pattern, and using a Macbeth densitometer (TD-931, manufactured by Macbeth) to measure the black resist pattern.

[0027] Hereinafter, various components and the like of the coloring composition for a black matrix of the present invention will be described.

[0028] [Coloring Material]

[0029] The coloring material is not particularly limited as long as it can turn the coloring composition into black or a hue simulating black, and known coloring materials can be used. Herein, "a hue simulating black" means a hue that is ideally black, but as long as it is a hue acceptable for the black matrix of a color filter for a liquid crystal display element. As the black matrix, it is necessary to be substantially achromatic without adding unnecessary colors. Further, if light leakage occurs from the black matrix, the contrast of the image will decrease. Therefore, from the perspective of absorbing all colors of light, as described above, it is ideally black. However, even if it is not completely achromatic, as long as it is within the range of hues without adding unnecessary colors to the image. In addition, hues that can absorb necessary light to maintain contrast are included in the range of hues simulating black.

[0030] Examples of the coloring material include black pigments, mixed pigments, and mixtures thereof.

[0031] Examples of the black pigment include carbon black, graphite, perylene-based pigments, lactam-based pigments, titanium black, and metal oxides, composite oxides, metal sulfides, metal sulfates, metal carbonates, etc. of copper, iron, manganese, cobalt, chromium, nickel, zinc, calcium, silver, etc. Among them, from the viewpoints of light shielding rate and image characteristics, carbon black and titanium black are preferred. Examples of the carbon black include furnace black, channel black, acetylene black, thermal black, lamp black, bone black, etc. In addition, either neutral carbon black or acidic carbon black can be used, or both can be used. It should be noted that the hue of the black pigment is not limited to achromatic black in color theory, and can also be black with a slight purple tint, black with a slight blue tint, or black with a slight red tint.

[0032] Examples of the mixed pigment include pigments that simulate black by mixing two or more pigments other than black pigments. Examples of the mixed pigment include pigments that simulate black by mixing two or more organic pigments selected from organic blue pigments, organic purple pigments, organic yellow pigments, organic red pigments, and organic orange pigments.

[0033] Examples of the organic 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, 22, 25, 27, 28, 29, 33, 35, 36, 56, 56:1, 60, 61, 61:1, 62, 63, 64, 66, 67, 68, 71, 72, 73, 74, 75, 76, 78, 79, etc.

[0034] Examples of purple organic pigments include C.I. Pigment Violet 1, 1:1, 2, 2:2, 3, 3:1, 3:3, 5, 5:1, 14, 15, 16, 19, 23, 25, 27, 29, 30, 31, 32, 37, 39, 40, 42, 44, 47, 49, 50, etc.

[0035] Examples of yellow organic pigments include C.I. Pigment Yellow 1, 1:1, 2, 3, 4, 5, 6, 9, 10, 12, 13, 14, 16, 17, 20, 24, 31, 32, 34, 35, 35:1, 36, 36:1, 37, 37:1, 40, 41, 42, 43, 48, 53, 55, 61, 62, 62:1, 63, 65, 73, 74, 75, 81, 83, 86, 87, 93, 94, 95, 97, 100, 101, 104, 105, 108, 109, 110, 111, 116, 117, 119, 120, 125, 126, 127, 127:1, 128, 129, 133, 134, 136, 137, 138, 139, 142, 147, 148, 150, 151, 153, 154, 155, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 172, 173, 174, 175, 176, 180, 181, 182, 183, 184, 185, 188, 189, 190, 191, 191:1, 192, 193, 194, 195, 196, 197, 198, 199, 200, 202, 203, 204, 205, 206, 207, 208, 213, etc.

[0036] As red organic pigments, examples include C.I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 14, 15, 16, 17, 21, 22, 23, 31, 32, 37, 38, 41, 47, 48, 48:1, 48:2, 48:3, 48:4, 49, 49:1, 49:2, 50:1, 52:1, 52:2, 53, 53:1, 53:2, 53:3, 57, 57:1, 57:2, 58:4, 60, 63, 63:1, 63:2, 64, 64:1, 68, 69, 81, 81:1, 81:2, 81:3, 81:4, 83, 88, 90:1, 97, 101, 101:1, 104, 108, 108:1, 109, 112, 113, 114, 122, 123, 144, 146, 147, 149, 151, 166, 168, 169, 170, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 184, 185, 187, 188, 190, 192, 193, 194, 200, 202, 206, 207, 208, 209, 210, 214, 215, 216, 217, 220, 221, 223, 224, 226, 227, 228, 230, 231, 232, 233, 235, 236, 237, 238, 239, 240, 242, 243, 245, 247, 249, 250, 251, 253, 254, 255, 256, 257, 258, 259, 260, 262, 263, 264, 265, 266, 267, 268, 269, 270, 271, 272, 273, 274, 275, 276, etc.

[0037] As orange organic pigments, examples include C.I. Pigment Orange 1, 2, 5, 13, 16, 17, 19, 20, 21, 22, 23, 24, 34, 36, 38, 39, 43, 46, 48, 49, 51, 55, 59, 61, 62, 64, 65, 67, 68, 69, 70, 71, 72, 73, 74, 75, 77, 78, 79, etc.

[0038] As a combination of the organic pigments, a combination of a blue organic pigment and at least two or more organic pigments selected from organic pigments of purple, yellow, red and orange is preferred.

[0039] The coloring material may also contain a pigment derivative as a dispersion aid. As the pigment derivative, a pigment derivative having an acidic group is preferably contained. The pigment derivative is a substance in which an acidic functional group is introduced into a pigment skeleton. Specific examples of the pigment skeleton include an azo pigment skeleton, a phthalocyanine pigment skeleton, an anthraquinone pigment skeleton, a triazine pigment skeleton, an acridine pigment skeleton, a perylene pigment skeleton, and the like. As the acidic group introduced into the pigment skeleton, a carboxyl group, a phosphoric acid group, and a sulfonic acid group are preferable. It should be noted that from the viewpoints of ease of synthesis and strength of acidity, a sulfonic acid group is preferable. In addition, the acidic group may be directly bonded to the pigment skeleton, but may also be bonded to the pigment skeleton via a hydrocarbon group such as an alkyl group or an aryl group, an ester, an ether, a sulfonamide, or a urethane bond.

[0040] In the total amount of the solid components of the coloring composition, the total content of the coloring material in the coloring composition is preferably 10% by mass or more, more preferably 20% by mass or more, further preferably 30% by mass or more, preferably 80% by mass or less, more preferably 70% by mass or less, and further preferably 60% by mass or less. Here, the solid components refer to components other than the dispersion medium described later in the coloring composition.

[0041] [Dispersant]

[0042] The coloring composition contains a dispersant. The dispersant has the following two parts: one part has the property of adsorbing to the coloring material, and the other part has an affinity for the dispersion medium. The dispersant adsorbs to the coloring material and has the effect of stabilizing the dispersion in the dispersion medium. There is no particular limitation on the dispersant, and it can be appropriately selected according to the types of the coloring material and the dispersion medium. As the dispersant, resin-type dispersants used in coloring compositions for color filters can be used. For example, polyester-based resin-type dispersants, (meth)acrylic acid-based resin-type dispersants, polyurethane-based resin-type dispersants, polyallylamine-based resin-type dispersants, carbodiimide-based resin-type dispersants, and the like can be cited.

[0043] As the resin-type dispersant, for example, the following dispersants can be cited.

[0044] (1) Reaction products of amino groups and / or imino groups of polyamine compounds (such as polyalkyleneamines such as polyallylamine, polyvinylamine, and polyethyleneimine) with at least one selected from polyesters, polyamides, and polyesteramides having free carboxyl groups.

[0045] (2) Carbodiimide-based compounds having at least one side chain selected from polyester side chains, polyether side chains, and polyacrylic acid side chains and basic nitrogen-containing groups in the molecule.

[0046] (3) Reaction products of polyalkyleneimines, amino compounds such as methyliminodipropylamine, and polyesters having free carboxyl groups.

[0047] (4) A reaction product formed by successively reacting an alcohol such as methoxypolyethylene glycol or a polyester having one hydroxyl group such as ε-caprolactone polyester, a compound having 2 to 3 isocyanate-reactive functional groups, and an aliphatic or heterocyclic hydrocarbon compound having an isocyanate-reactive functional group and a tertiary amine group with the isocyanate groups of a polyisocyanate compound.

[0048] (5) A reaction product obtained by reacting a polyisocyanate compound and a hydrocarbon compound having an amino group with a polymer of an acrylate having an alcoholic hydroxyl group.

[0049] (6) A reaction product formed by adding a polyether chain to an amine compound.

[0050] (7) A reaction product formed by reacting a compound having an amino group with a compound having an isocyanate group.

[0051] (8) A reaction product obtained by reacting a linear polymer having a free carboxyl group and an organic amine compound having one secondary amino group with a polyepoxide compound.

[0052] (9) A reaction product of a polycarbonate compound having a functional group reactive with an amino group at one end and a polyamine compound.

[0053] (10) A copolymer of at least one selected from (meth)acrylate esters such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, octadecyl (meth)acrylate, benzyl (meth)acrylate, etc., at least one selected from polymerizable monomers containing basic groups such as (meth)acrylamide, N-hydroxymethylamide, vinylimidazole, vinylpyridine, a monomer having an amino group and a polycaprolactone skeleton, etc., and at least one selected from styrene, styrene derivatives, and other polymerizable monomers.

[0054] (11) A (meth)acrylic block copolymer composed of blocks having basic groups such as a tertiary amine group and a quaternary ammonium salt group and blocks having no basic functional groups.

[0055] (12) A compound obtained by Michael addition of a polycarbonate compound to polyallylamine.

[0056] (13) A carbodiimide compound having at least one polybutadiene chain and a basic nitrogen-containing group respectively.

[0057] (14) A carbodiimide compound having at least one side chain having an amide group and a basic nitrogen-containing group respectively in the molecule.

[0058] (15) A polyurethane compound having a structural unit containing an ethylene oxide chain and a propylene oxide chain and an amino group quaternized by a quaternizing agent.

[0059] (16) 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 is 15 to 85% relative to the total of the isocyanate groups derived from the isocyanate compound having an isocyanurate ring in the molecule of the compound and the urethane bonds and urea bonds formed by the reaction of the isocyanate group with the active hydrogen group.

[0060] Among these resin-type dispersants, polyurethane-based resin-type dispersants containing basic groups, polyester-based resin-type dispersants containing basic groups, and (meth)acrylic acid-based resin-type dispersants containing basic groups are more preferred, and polyurethane-based resin-type dispersants containing amino groups, polyester-based resin-type dispersants containing amino groups, and (meth)acrylic acid-based resin-type dispersants containing amino groups are further preferred. Polyurethane-based resin-type dispersants containing basic groups are particularly preferred, and polyurethane-based resin-type dispersants containing basic groups (amino groups) having at least one selected from polyester chains, polyether chains, and polycarbonate chains are preferred.

[0061] The resin-type dispersant is preferably a resin (polymer) having a polar functional group. It is considered that the polar functional group adsorbs to the pigment and has the effect of stabilizing the dispersion in the dispersion medium. Examples of the polar functional group include primary amino group, secondary amino group, tertiary amino group, quaternary ammonium salt group, imino group, amide group, nitrogen-containing heterocyclic group, carboxyl group, phosphate group, sulfonic acid group, etc. As the polar functional group, at least one selected from primary amino group, secondary amino group, tertiary amino group, quaternary ammonium salt group, imino group, amide group, and nitrogen-containing heterocyclic group is preferred.

[0062] Examples of the resin-type dispersant include polymers having an amine value but no acid value (polymers having an amine value greater than 0 mgKOH / g and an acid value of 0 mgKOH / g), polymers having an acid value but no amine value (polymers having an acid value greater than 0 mgKOH / g and an amine value of 0 mgKOH / g), polymers having both an amine value and an acid value (polymers having both an amine value and an acid value greater than 0 mgKOH / g), and polymers having neither an acid value nor an amine value (polymers having both an amine value and an acid value of 0 mgKOH / g).

[0063] As the resin-type dispersant, a polymer having an amine value (a polymer having an amine value greater than 0 mgKOH / g) is preferred. The amine value of the resin-type dispersant is preferably 10 mgKOH / g or more and 200 mgKOH / g or less. If the amine value is 10 mgKOH / g or more, the dispersion stabilization effect is further improved, and if the amine value is 200 mgKOH / g or less, the solubility of the coloring composition in the alkali-developing liquid is good and the pattern processability is improved. In addition, the acid value of the resin-type dispersant is preferably less than 20 mgKOH / g.

[0064] With respect to 100 parts by mass of the coloring material, the content of the dispersant in the coloring composition is preferably 1 part by mass or more, more preferably 2 parts by mass or more, further preferably 5 parts by mass or more, particularly preferably 10 parts by mass or more, preferably 200 parts by mass or less, more preferably 100 parts by mass or less, and further preferably 50 parts by mass or less.

[0065] [Dispersion medium]

[0066] The coloring composition contains a dispersion medium. As the dispersion medium, any medium can be appropriately selected and used as long as it can disperse or dissolve other components (solid components) constituting the coloring composition, does not react with these components, and has moderate volatility. As the dispersion medium, for example, conventionally known organic solvents can be used, such as: ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monon-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monon-butyl ether, propylene glycol tert-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monon-butyl ether, methoxymethyl pentanol, 1-methoxy-2-propanol, dipropylene glycol monoethyl ether, dipropylene glycol monomethyl ether, 3-methyl-3-methoxybutanol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, tripropylene glycol monomethyl ether, etc. glycol monoalkyl ethers; ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, dipropylene glycol dimethyl ether, etc. glycol dialkyl ethers; ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monon-butyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monon-butyl ether acetate, methoxybutyl acetate, methoxypentyl acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monon-butyl ether acetate, dipropylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether acetate, triethylene glycol monoethyl ether acetate, 3-methyl-3-methoxybutyl acetate, etc. glycol alkyl ether acetates; ethylene glycol diacetate, 1,3-butanediol diacetate, 1,6-hexanediol diacetate, etc. glycol diacetates; cyclohexyl acetate, etc. alkyl acetates; pentyl ether, propyl ether, diethyl ether, dipropyl ether, diisopropyl ether, butyl ether, dipentyl ether, ethyl isobutyl ether, dihexyl ether, etc. ethers; acetone, methyl ethyl ketone, 2-heptanone, methyl isopropyl ketone, methyl isopentyl ketone, diisopropyl ketone, diisobutyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl pentyl ketone, methyl butyl ketone, methyl hexyl ketone, methyl nonyl ketone, methoxymethyl pentanone, etc. ketones; ethanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, glycerol, benzyl alcohol, diacetone alcohol, etc. monohydric or polyhydric alcohols; n-pentane, n-octane, diisobutylene, n-hexane, hexene, isoprene, dipentene, dodecane, etc. aliphatic hydrocarbons; cyclohexane, methylcyclohexane, methylcyclohexene, dicyclohexane, etc. alicyclic hydrocarbons; benzene, toluene, xylene, isopropylbenzene, etc. aromatic hydrocarbons;Amyl formate, ethyl formate, ethyl acetate, butyl acetate, propyl acetate, amyl acetate, methyl isobutyrate, ethylene glycol acetate, ethyl propionate, propyl propionate, butyl butyrate, isobutyl butyrate, methyl isobutyrate, ethyl octanoate, butyl stearate, ethyl benzoate, methyl 3 - ethoxypropionate, ethyl 3 - ethoxypropionate, methyl 3 - methoxypropionate, ethyl 3 - methoxypropionate, propyl 3 - methoxypropionate, butyl 3 - methoxypropionate, butyl 3 - methyl - 3 - methoxypropionate, γ - butyrolactone, ethyl 2 - hydroxypropionate and other chain or cyclic esters; alkoxycarboxylic acids such as 3 - methoxypropionic acid, 3 - ethoxypropionic acid; halogenated hydrocarbons such as butane chloride, pentane chloride; ether ketones such as methoxymethyl pentanone; nitriles such as acetonitrile, benzonitrile, etc.

[0067] From the viewpoints of the dispersibility of coloring materials, the solubility of dispersants, the coatability of coloring compositions, etc., the organic solvent is preferably diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, cyclohexanone, 2 - heptanone, amyl formate, ethyl 2 - hydroxypropionate, butyl 3 - methyl - 3 - methoxypropionate, ethyl 3 - methoxypropionate, methyl 3 - ethoxypropionate, etc. The dispersion medium contained in the coloring composition may be only one kind or may be multiple kinds.

[0068] There is no particular limitation on the content of the dispersion medium in the coloring composition, and it can be appropriately adjusted. The content of the dispersion medium in the coloring composition is usually 99% by mass or less. In addition, considering the viscosity suitable for coating the coloring composition, the content of the dispersion medium in the coloring composition is preferably 50% by mass or more.

[0069] [Phosphite ester]

[0070] The coloring composition of the present invention contains a phosphite ester represented by the general formula (5). By containing the phosphite ester, formaldehyde generated from the compounding agents in the coloring composition can be reduced.

[0071]

[0072] In the general formula (5), R 51 represents an alkyl group having 1 to 20 carbon atoms, R 52 and R 53 each independently represents a hydrocarbon group, R 52 and R 53 may also be bonded to each other to form a cyclic structure, and the compound represented by the general formula (5) may also form a dimer or trimer by bonding through R 52 or R 53 bonding.

[0073] R 51represents an alkyl group having 1 to 20 carbon atoms. Examples of the alkyl group having 1 to 20 carbon atoms include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, isopentyl, hexyl, isohexyl, heptyl, isoheptyl, octyl, isooctyl, nonyl, isononyl, decyl,isodecyl, undecyl, isoundecyl, dodecyl, isododecyl, tridecyl, isotridecyl, tetradecyl, isotetradecyl, hexadecyl, isohexadecyl, octadecyl, isooctadecyl, icosyl, etc. Among them, ethyl, butyl, and isodecyl are preferred.

[0074] As R 52 or R 53 The hydrocarbon group represented may include an alkyl group which may have a substituent and an aromatic group which may have a substituent. The total number of carbon atoms of the alkyl group which may have a substituent is preferably 1 to 20, more preferably 1 to 15. Examples of the alkyl group include linear alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, isopentyl, hexyl, isohexyl, heptyl, isoheptyl, octyl, isooctyl, nonyl, isononyl, decyl,isodecyl, undecyl, isoundecyl, dodecyl, isododecyl, tridecyl, isotridecyl, tetradecyl, isotetradecyl, hexadecyl, isohexadecyl, octadecyl, isooctadecyl, icosyl, etc.; cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, methylcyclopentyl, methylcyclohexyl, etc. Examples of the aromatic group include phenyl, tolyl, xylyl, cumenyl, mesityl, benzyl, phenethyl, styryl, cinnamyl, diphenylmethyl, triphenylmethyl, ethylphenyl, propylphenyl, butylphenyl, pentylphenyl, hexylphenyl, heptylphenyl, octylphenyl, nonylphenyl, decylphenyl, undecylphenyl, dodecylphenyl, etc.

[0075] R 52 and R 53 may also be bonded to each other to form a cyclic structure. Examples of the ring formed by the bonding of R 52 and R 53 to each other include the following partial structures. Further, the compound represented by the general formula (5) may also form a dimer or a trimer by the bonding of R 52 or R 53 bonding.

[0076]

[0077] As the phosphite represented by the general formula (5), the phosphite represented by the general formula (5-1) and / or the phosphite represented by the general formula (5-2) are preferred.

[0078]

[0079] In the general formula (5-1), R 51represents an alkyl group having 1 to 20 carbon atoms, and when there are a plurality of Rs 51 they may be the same or different from each other.

[0080]

[0081] In the general formula (5-2), R 51 represents an alkyl group having 1 to 20 carbon atoms, and when there are a plurality of Rs 51 they may be the same or different from each other.

[0082] Examples of the phosphite represented by the general formula (5) include trialkyl phosphites such as triethyl phosphite, tripropyl phosphite, triisopropyl phosphite, tributyl phosphite, tripentyl phosphite, trihexyl phosphite, trioctyl phosphite, triisooctyl phosphite, trinonyl phosphite, tridecyl phosphite, triisodecyl phosphite; alkyl diphenyl phosphites such as octyl diphenyl phosphite, decyl diphenyl phosphite, diphenyl isodecyl phosphite, tridecyl diphenyl phosphite, hexadecyl diphenyl phosphite; and dimers of phosphites such as 3,9-bis(octadecyloxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5,5]undecane, 3,9-bis(isodecyloxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5,5]undecane. Among them, trialkyl phosphites are preferred, and triethyl phosphite, tributyl phosphite, and triisodecyl phosphite are more preferred.

[0083] The phosphite represented by the general formula (5) contained in the coloring composition may be only one kind or a plurality of kinds.

[0084] With respect to 100 parts by mass of the dispersant, the content of the phosphite represented by the general formula (5) in the coloring composition is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more, further preferably 1 part by mass or more, particularly preferably 5 part by mass or more, preferably 100 parts by mass or less, more preferably 80 parts by mass or less, further preferably 60 parts by mass or less, and particularly preferably 25 parts by mass or less.

[0085] When formulating the coloring composition, the phosphite may be added to the coloring material and / or the dispersant before mixing the coloring material and the dispersant, may be added when mixing the coloring material and the dispersant, or may be added to the mixture after mixing the coloring material and the dispersant.

[0086] [Phenolic antioxidant]

[0087] The coloring composition of the present invention may contain a known phenolic antioxidant. By containing the phenolic antioxidant, the amount of formaldehyde in the coloring composition can be further reduced. It is considered that the reason for the reduction in the amount of formaldehyde is that the oxidative degradation of phosphite can be inhibited. In addition, by containing the phenolic antioxidant, the dispersion stability of the coloring material can be improved even when the coloring composition contains a large amount of binder resin. Especially when the content of the binder resin in the total solid content of the coloring composition is 30% by mass or more, the effect of improving the dispersion stability is more remarkable.

[0088] The phenolic antioxidant refers to an antioxidant having a compound having at least one hydroxyl group on at least one benzene ring. Specifically, antioxidants having the following chemical structures can be cited: When the hydroxyl group on the benzene ring is taken as the 1-position, it has a substituent that can block other molecules having free radicals on at least one of the 2-position, 4-position, and 6-position or on at least one of the 3-position, 4-position, and 6-position, such as a bulky substituent (for example, a substituent whose carbon atom after bonding to the benzene ring is a quaternary carbon atom (specific examples: tert-butyl group, adamantyl group, etc.)).

[0089] As the phenolic antioxidant, a compound represented by the general formula (6) is preferred.

[0090]

[0091] In the general formula (6), R 61 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, wherein the carbon atom of R 61 after bonding to the benzene ring is a primary to tertiary carbon atom, R 62 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R 63 represents a group in which any one or more carbon atoms of a hydrocarbon group having 2 to 20 carbon atoms are substituted with an ester group or an ether group or represents a hydrocarbon group having 1 to 20 carbon atoms, and n represents a number from 1 to 6.

[0092] R 61 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. As the alkyl group having 1 to 8 carbon atoms, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, isopentyl, hexyl, isohexyl, heptyl, isoheptyl, octyl, isooctyl, etc. can be cited. Among them, from the viewpoint of a large synergistic effect of antioxidant performance, a hydrogen atom, a methyl group, and an ethyl group are preferred, a hydrogen atom and a methyl group are more preferred, and a hydrogen atom is further preferred. It should be noted that the carbon atom of R 61 after bonding to the benzene ring will not be a quaternary carbon atom. For example, a group such as a tert-butyl group is not suitable as R 61 .

[0093] R 62represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Examples of the alkyl group having 1 to 4 carbon atoms include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, and tert-butyl, and methyl is preferred.

[0094] R 63 represents a group in which any one or more carbon atoms of a hydrocarbon group having 2 to 20 carbon atoms are substituted with an ester group or an ether group, or represents a hydrocarbon group having 1 to 20 carbon atoms. Examples of the hydrocarbon group having 1 to 20 carbon atoms include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, isopentyl, hexyl, isohexyl, heptyl, isoheptyl, octyl, isooctyl, nonyl, isononyl, decyl, isodecyl, undecyl, isoundecyl, dodecyl, isododecyl, tridecyl, isotridecyl, tetradecyl, isotetradecyl, hexadecyl, isohexadecyl, octadecyl, isooctadecyl, and eicosyl; alkenyl groups such as vinyl, allyl, propenyl, isopropenyl, butenyl, isobutenyl, pentenyl, isopentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tetradecenyl, hexadecenyl, and octadecenyl; aryl groups such as phenyl, tolyl, xylyl, cumenyl, mesityl, benzyl, phenethyl, styryl, cinnamyl, diphenylmethyl, triphenylmethyl, ethylphenyl, propylphenyl, butylphenyl, pentylphenyl, hexylphenyl, heptylphenyl, octylphenyl, nonylphenyl, decylphenyl, undecylphenyl, and dodecylphenyl; and cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, methylcyclopentyl, and methylcyclohexyl. Among them, an alkyl group is preferred, and an alkyl group having 1 to 10 carbon atoms is more preferred. The above group is the group when the value of n in the general formula (6) is 1. When the value of n is 2, it is the group obtained by removing any one hydrogen atom from the above group. When the value of n is 3, it is the group obtained by removing any two hydrogen atoms from the above group. The value of n represents a number from 1 to 6. However, from the viewpoints of good antioxidant performance and good raw material conditions, a number from 1 to 4 is preferred, and a number of 2 or 3 is more preferred.

[0095] R 63 may also be a group in which any one or more carbon atoms of a hydrocarbon group having 2 to 20 carbon atoms are substituted with an ester group or an ether group. This group may have only one of an ester group and an ether group, may have both at the same time, or may have a plurality of them. It should be noted that from the viewpoint of the synergistic effect with phosphite, R 63 is preferably a hydrocarbon group having 1 to 20 carbon atoms.

[0096] As specific examples of the compound of the general formula (6), 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 4,4'-butylidenebis(6-tert-butyl-m-cresol), [ethylenebis(oxyethylene)]bis[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate], bis[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionic acid](2,4,8,10-tetraoxaspiro[5,5]undecane-3,9-diyl)bis(2,2-dimethyl-2,1-ethanediyl))ester, etc. can be cited.

[0097] The phenolic antioxidant contained in the coloring composition may be only one kind or may be a plurality of kinds.

[0098] Relative to 100 parts by mass of the dispersant, the content of the phenolic antioxidant in the coloring composition is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more, further preferably 1 part by mass or more, preferably 25 parts by mass or less, more preferably 10 parts by mass or less, further preferably 5 parts by mass or less, and particularly preferably 2 parts by mass or less.

[0099] When formulating the coloring composition, the phenolic antioxidant can be added to the coloring material and / or the dispersant before mixing the coloring material and the dispersant, can also be added when mixing the coloring material and the dispersant, or can be added to the mixture after mixing the coloring material and the dispersant. It should be noted that the phenolic antioxidant is preferably added to the coloring material and / or the dispersant before mixing the coloring material and the dispersant.

[0100] [Binder resin]

[0101] The coloring composition of the present invention may contain a binder resin (excluding the above-mentioned dispersant). As the binder resin, alkali-soluble resins, polymerizable compounds (polymerizable resins, monomers having one polymerizable unsaturated bond in the molecule, monomers having two or more polymerizable unsaturated bonds in the molecule, oligomers, etc.), thermosetting resins, thermoplastic resins, etc. can be cited. These can be used alone or in combination of two or more. Among them, alkali-soluble resins and / or polymerizable compounds are preferred.

[0102] The binder resin is a compound different from the above-mentioned resin-type dispersant. The binder resin is preferably a binder resin having an amine value of 0 mgKOH / g.

[0103] In the total solid content of the coloring composition, based on the total amount of the binder resin used, the content of the binder resin in the coloring composition is preferably 1% by mass or more, more preferably 2% by mass or more, further preferably 5% by mass or more, preferably 70% by mass or less, more preferably 60% by mass or less, and further preferably 50% by mass or less.

[0104] (Alkali-soluble resin)

[0105] As the alkali-soluble resin, there is no particular limitation as long as it functions as a binder for the coloring material and is soluble in a developer, preferably an alkaline developer, used in the development process when preparing a color filter. The alkali-soluble resin is preferably a resin having acidic groups such as carboxyl groups and phenolic hydroxyl groups.

[0106] Examples of the alkali-soluble resin include: a resin obtained by adding an unsaturated monobasic acid to at least a part of the epoxy groups in a copolymer of an epoxy group-containing (meth)acrylate and other radically polymerizable monomers, or a resin obtained by adding a polyanhydride to at least a part of the hydroxyl groups generated by the addition reaction; a linear resin having a carboxyl group in the main chain; a resin obtained by adding an epoxy group-containing unsaturated compound to the carboxyl group part of a resin having a carboxyl group; a (meth)acrylic resin; an epoxy (meth)acrylate resin having a carboxyl group, etc. These can be used alone or in combination of two or more.

[0107] Specific examples of the alkali-soluble resin include: an acid group-containing copolymer resin obtained by radically polymerizing an unsaturated monomer component having an acidic group and at least one monomer component selected from styrene, methylstyrene, 2-hydroxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, allyl (meth)acrylate, benzyl (meth)acrylate, methyl (meth)acrylate, polystyrene macromonomer, poly(methyl)acrylate macromonomer, etc. Examples of the unsaturated monomer component having an acidic group include (meth)acrylic acid, itaconic acid, maleic acid, maleic anhydride, monoalkyl maleate, citraconic acid, citraconic anhydride, monoalkyl citraconate, 2-sulfoethyl (meth)acrylate, butyl (meth)acrylamide sulfonic acid, 2-sulfoethyl (meth)acrylate, etc.

[0108] The alkali-soluble resin may also be a resin having a carbon-carbon double bond capable of radical polymerization in the side chain. By having a double bond in the side chain, the photocurability of the coloring composition of the present invention is improved, and thus the resolution and adhesion can be further improved. As a method for introducing a carbon-carbon double bond capable of radical polymerization into the side chain, for example, a method of reacting a compound such as glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, or o-(or m- or p-)vinylbenzyl glycidyl ether with the acidic group of the alkali-soluble resin can be cited.

[0109] The weight-average molecular weight (Mw) of the alkali-soluble resin is preferably 500 or more, more preferably 1,000 or more, preferably 200,000 or less, and more preferably 100,000 or less. If the Mw of the alkali-soluble resin is 500 or more, the heat resistance, film strength, etc. of the colored layer formed from the coloring composition are good. If the Mw is 200,000 or less, the alkali developability of the coating film is better.

[0110] The acid value of the alkali-soluble resin is preferably 10 mgKOH / g or more, more preferably 20 mgKOH / g or more, preferably 300 mgKOH / g or less, and more preferably 200 mgKOH / g or less. If the acid value of the alkali-soluble resin is 10 mgKOH / g or more, the alkali developability when the coloring composition is used as the colored layer is better. If it is 300 mgKOH / g or less, the film strength, etc. are good. In addition, the amine value of the alkali-soluble resin is preferably less than 10 mgKOH / g.

[0111] With respect to 100 parts by mass of the coloring material, the content of the alkali-soluble resin in the coloring composition is preferably 5 parts by mass or more, more preferably 15 parts by mass or more, further preferably 30 parts by mass or more, preferably 200 parts by mass or less, and more preferably 120 parts by mass or less. In the total solid content of the coloring composition, the content of the alkali-soluble resin in the coloring composition is preferably 1% by mass or more, more preferably 2% by mass or more, further preferably 5% by mass or more, preferably 70% by mass or less, more preferably 60% by mass or less, and further preferably 50% by mass or less.

[0112] (Polymerizable compound)

[0113] As the polymerizable resin of the polymerizable compound, resins in which a crosslinkable group such as (meth)acrylic acid compound or cinnamic acid is introduced into a linear polymer having a reactive substituent such as a hydroxyl group, carboxyl group, or amino group via an isocyanate group, aldehyde group, epoxy group, etc. can be used. Polymers obtained by semi-esterifying a linear polymer containing an acid anhydride such as a styrene-maleic anhydride copolymer or an α-olefin-maleic anhydride copolymer with a (meth)acrylic acid compound having a hydroxyl group such as (meth)acrylic acid hydroxyalkyl ester can also be used.

[0114] Examples of the monomer having one polymerizable unsaturated bond in the molecule as the polymerizable compound include (meth)acrylic acid alkyl esters such as methyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate; aralkyl (meth)acrylates such as benzyl (meth)acrylate; alkoxyalkyl (meth)acrylates such as butoxyethyl (meth)acrylate; aminoalkyl (meth)acrylates such as N,N-dimethylaminoethyl (meth)acrylate; (meth)acrylates of polyalkylene glycol alkyl ethers such as diethylene glycol ethyl ether, triethylene glycol butyl ether, dipropylene glycol methyl ether; (meth)acrylates of polyalkylene glycol aryl ethers such as hexaethylene glycol phenyl ether; isobornyl (meth)acrylate; glycerol (meth)acrylate; 2-hydroxyethyl (meth)acrylate, etc.

[0115] Examples of the monomer having two or more polymerizable unsaturated bonds in the molecule as the polymerizable compound include bisphenol A di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, di(meth)acrylated glycerol, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, etc.

[0116] In the total amount of the solid components of the coloring composition, the content of the polymerizable compound in the coloring composition is preferably 3% by mass or more, more preferably 5% by mass or more, preferably 50% by mass or less, and more preferably 20% by mass or less. If the content of the polymerizable compound is too small, sufficient curability may not be obtained. If the amount of the polymerizable compound is too large, the alkali developability of the coloring composition of the present invention tends to decrease, and substrate contamination and film residue are likely to occur on the unexposed part of the substrate or on the light-shielding layer.

[0117] (Thermosetting resin, thermoplastic resin)

[0118] Examples of the thermosetting resin or 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, cellulose, polybutadiene, polyimide resin, benzoguanamine resin, melamine resin, urea resin, etc.

[0119] [Photoinitiator]

[0120] The coloring composition preferably contains a photopolymerization initiator. Thereby, radiation sensitivity can be imparted to the coloring composition. The photopolymerization initiator is a compound that generates an active substance capable of initiating the polymerization of a crosslinking agent upon exposure to radiation such as visible light, ultraviolet light, far-infrared light, electron beams, X-rays, etc.

[0121] Examples of the photopolymerization initiator include thioxanthone compounds, acetophenone compounds, bisimidazole compounds, triazine compounds, O-acyl oxime compounds, onium salt compounds, benzoin compounds, benzophenone compounds, α-diketone compounds, polynuclear quinone compounds, diazo compounds, imide sulfonate compounds, aminoketone compounds, etc. The photopolymerization initiator can be used alone or in combination of two or more.

[0122] In the total solid content of the coloring composition, the content of the photopolymerization initiator in the coloring composition of the present invention is preferably 1% by mass or more, more preferably 2% by mass or more, preferably 20% by mass or less, and more preferably 10% by mass or less. In this case, if the content of the photopolymerization initiator is too small, the exposure curing may be insufficient, and if the content is too large, the formed coloring layer may easily peel off from the substrate during development.

[0123] [Other additives]

[0124] Examples of other additives include sensitizing dyes, thermal polymerization inhibitors, nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, plasticizers, organic carboxylic acid compounds, organic carboxylic anhydrides, pH adjusters, antioxidants other than the above phenolic antioxidants, ultraviolet absorbers, light stabilizers, preservatives, mildew inhibitors, antiaggregation agents, adhesion improvers, development improvers, storage stabilizers, etc.

[0125] [Method for preparing the coloring composition]

[0126] The coloring composition can be formulated by mixing a coloring material, a dispersant, a dispersion medium, a phosphite ester, and a phenolic antioxidant, a binder resin, a photopolymerization initiator, a light diffusing agent (such as precipitated barium sulfate), and other compounding agents as required. Mixing can be carried out, for example, using a paint stirrer, a bead mill, a ball mill, a dissolver, a kneader, or other mixing and dispersing machines. The coloring composition is preferably filtered after mixing. There is no particular limitation on the method of mixing the various materials. For example, the following methods can be cited: a method of mixing all the materials together simultaneously; a method of mixing the coloring material, the dispersant, and the dispersion medium to pre-disperse the coloring material first, and then mixing the other materials in the dispersion liquid of the coloring material; a method of mixing the coloring material, the dispersant, and a part of the other materials to prepare a base liquid for dispersing the coloring material, and then mixing the other materials in the base liquid for dispersing the coloring material, etc. The coloring composition has excellent dispersibility and the generation of formaldehyde is suppressed, so it can be suitably used for a black matrix.

[0127] <Color filter>

[0128] The color filter of the present invention has color pixels that transmit light of the three primary colors of red (R), green (G), and blue (B) on a transparent substrate and a black matrix formed from the above coloring composition.

[0129] As a method for preparing a color filter, for example, the following method can be cited. First, on a transparent substrate such as a thermoplastic resin sheet such as a polyester resin, a polyolefin resin, a polycarbonate resin, a polymethyl methacrylate resin, a thermosetting resin sheet such as an epoxy resin, an unsaturated polyester resin, a poly(meth)acrylic acid resin, or various glasses, for example, the coloring composition for the black matrix of the present invention is coated, and then soft baking (pre-bake) is carried out to evaporate the solvent (dispersion medium) to form a coating film. Then, after exposing the coating film through a photomask, development is carried out using an alkali developer (an aqueous solution containing an organic solvent or a surfactant and an alkaline compound, etc.) to dissolve and remove the unexposed part of the coating film to form a black pattern (black matrix). Then, after post-baking as required, the same operations are sequentially repeated for red (R), green (G), and blue (B), whereby a color filter having a pixel array of the three primary colors of red, green, and blue arranged on the substrate is obtained. However, the order of forming the respective color pixels in the present invention is not limited to the above order.

[0130] When coating the coloring composition on the substrate, appropriate coating methods such as spraying, roll coating, spin coating, slit die coating, bar coating, etc. can be adopted, but spin coating and slit die coating are particularly preferably adopted.

[0131] After forming a protective film on the pixel pattern obtained as required, a transparent conductive film (such as ITO (indium tin oxide)) is formed by sputtering. After forming the transparent conductive film, a partition can be further formed to produce a color filter.

[0132] Since the formaldehyde generation of the color filter of the present invention is suppressed and the dimensional accuracy is high, etc., it can be suitably used for color liquid crystal display elements, color camera tube elements, color sensors, organic electroluminescent display elements, electronic paper, etc.

[0133] Examples

[0134] The present invention will be further described in detail below with reference to specific examples. The present invention is not limited by any of the following examples, and appropriate changes can be made for implementation within the scope of not changing its gist.

[0135] <Evaluation method>

[0136] (Dispersion stability)

[0137] Respectively collect each pigment dispersion base liquid and coloring composition into glass bottles, seal them tightly, and store them at room temperature for 7 days. Visually observe each pigment dispersion base liquid and coloring composition after storage, and evaluate them according to the following evaluation criteria.

[0138] A: No thickening and sedimentation are found.

[0139] B: Thickening or sedimentation that can be restored by gently shaking is found.

[0140] C: Thickening or sedimentation that cannot be restored even by vigorous shaking is found.

[0141] (Developability of resist pattern)

[0142] Spin coat each coloring composition on a glass substrate with a film thickness of 1 μm using a spin coater, and bake it at 100 °C for 3 minutes. Then, use a mask that can obtain a grid pattern with a line width of 25 μm and an area ratio of cured part to uncured part of 20:80, and use a high-pressure mercury lamp to expose it with a UV cumulative light amount of 400 mJ / cm 2 Perform exposure. Develop the obtained coating film with a 0.05% aqueous potassium hydroxide solution, and evaluate the developability according to the time for removing the coloring composition in the unexposed part according to the following evaluation criteria.

[0143] A: It can be completely removed within 30 seconds.

[0144] B: It can be completely removed within more than 30 seconds and within 60 seconds.

[0145] C: It cannot be completely removed even after more than 60 seconds.

[0146] (Developing latitude of resist pattern)

[0147] Each coloring composition was coated on a glass substrate with a film thickness of 1 μm using a spin coater and pre-baked at 100 °C for 3 minutes. Then, using a mask with a grid pattern having a line width of 25 μm and an area ratio of cured part to uncured part of 20:80, and a high-pressure mercury lamp, exposure was carried out with a cumulative UV light amount of 400 mJ / cm 2 The obtained coating film was developed using a 0.05% aqueous potassium hydroxide solution, and the time from when the unexposed part of the coloring composition was removed until the resist composition of the cured part was removed was measured, and the development latitude was evaluated according to the following evaluation criteria.

[0148] A: The time from when the unexposed part of the coloring composition was removed until the resist composition of the cured part was removed was 60 seconds or more.

[0149] B: The time from when the unexposed part of the coloring composition was removed until the resist composition of the cured part was removed was more than 30 seconds and less than 60 seconds.

[0150] C: The time from when the unexposed part of the coloring composition was removed until the resist composition of the cured part was removed was less than 30 seconds.

[0151] (Formaldehyde detection amount)

[0152] 0.5 g of the coloring composition was injected into a cylinder filled with silica gel impregnated with DNPH (2,4-dinitrophenylhydrazine) (manufactured by Waters Corporation, Sep Pak (registered trademark) DNPH-Silica Plus Cartridge (product number: WAT037500)), and left standing at room temperature for 2 hours.

[0153] It was eluted with 4 mL of acetonitrile and made up to 5 mL. Using a liquid chromatograph (manufactured by Shimadzu Corporation, trade name: LC-10AD, chromatographic column: Pro C18 RS (4.6 × 250 mm, 5 μm (manufactured by YMC Co., Ltd.)), mobile phase: acetonitrile / ultrapure water = 65:35 solution, column temperature: 40 °C, flow rate: 1.0 mL / min, detection wavelength: 360 nm), and using two aldehyde-DNPH mixed standard solutions (0.1 μg aldehyde / μL acetonitrile, manufactured by Wako Pure Chemical Industries, Ltd.) as standards, measurement was carried out. The amount of formaldehyde was calculated from the measurement results.

[0154] (Amine value)

[0155] The amine value represents the mass of potassium hydroxide (KOH) equivalent to the alkaline component equivalent of 1 g of the solid component. The sample to be measured is dissolved in tetrahydrofuran, and using a potentiometric titration device (trade name: GT-06, manufactured by Mitsubishi Chemical Corporation), the resulting solution is neutralized and titrated with a 0.1 mol / L hydrochloric acid / 2-propanol solution. The inflection point of the titration pH curve is taken as the titration end point, and the amine value (B) is calculated according to the following formula.

[0156] B = 56.11 × Vs × 0.1 × f / w

[0157] B: Amine value (mgKOH / g)

[0158] Vs: Volume of 0.1 mol / L hydrochloric acid / 2-propanol solution required for titration (mL)

[0159] f: Titration factor of 0.1 mol / L hydrochloric acid (2-propanol-based)

[0160] w: Mass of the sample to be measured (g) (converted value of solid component)

[0161] (Acid value)

[0162] The acid value represents the mass of potassium hydroxide required to neutralize the acidic component equivalent to 1 g of the solid component. The sample to be measured is dissolved in tetrahydrofuran, a few drops of phenolphthalein ethanol solution are added as an indicator, and it is neutralized and titrated with a 0.1 mol / L potassium hydroxide / ethanol solution. The acid value (A) is calculated according to the following formula.

[0163] A = 56.11 × Vs × 0.1 × f / w

[0164] A: Acid value (mgKOH / g)

[0165] Vs: Volume of 0.1 mol / L potassium hydroxide / ethanol solution required for titration (mL)

[0166] f: Titration factor of 0.1 mol / L potassium hydroxide / ethanol solution

[0167] w: Mass of the sample to be measured (g) (converted value of solid component)

[0168] (Preparation of pigment dispersion base liquid)

[0169] (Pigment dispersion base liquid No.1 - 12, 14 - 16)

[0170] Mix various materials together according to the ratios shown in Table 1, and knead them in a bead mill for one day and night to prepare the pigment dispersion base liquid. The dispersion stabilities of pigment dispersion base liquids No.1 - 12, 14 - 16 are all good.

[0171] (Preparation of pigment dispersion base liquid No.13)

[0172] Mix together all the materials shown in Table 1 except the phosphite ester. After kneading with a bead mill for a whole day and night, add the phosphite ester to the kneaded mixture to prepare a pigment dispersion base liquid. The pigment dispersion base liquid No. 13 has good dispersion stability.

[0173] Table 1

[0174]

[0175] Table 2

[0176]

[0177] The materials used in Tables 1 and 2 are as follows.

[0178] SB250: Carbon black (manufactured by Cabot Corporation, trade name "Special Black 250")

[0179] PY185: C.I. Pigment Yellow 185

[0180] PV29: C.I. Pigment Violet 29

[0181] PB60: C.I. Pigment Blue 60

[0182] Dispersant 1: Amino group-containing polyurethane resin type dispersant (acid value 0 mgKOH / g, amine value 36 mgKOH / g)

[0183] Dispersant 2: Amino group-containing polyurethane resin type dispersant (acid value 0 mgKOH / g, amine value 45 mgKOH / g)

[0184] Dispersant 3: Amino group-containing (meth)acrylic resin type dispersant (acid value 0 mgKOH / g, amine value 63 mgKOH / g)

[0185] Dispersant 4: Amino group-containing polyester amide resin type dispersant (acid value 17 mgKOH / g, amine value 10 mgKOH / g)

[0186] Phthalocyanine series (a pigment derivative having a copper phthalocyanine series pigment skeleton, manufactured by Lubrizol Corporation, trade name "Solsperse (registered trademark) 5000")

[0187] Alkali-soluble resin: Benzyl methacrylate / methacrylic acid copolymer, acid value 100 mgKOH / g, amine value 0 mgKOH / g, weight average molecular weight 30,000

[0188] TEP: Triethyl phosphite

[0189] TIDP: Triisodecyl phosphite

[0190] BBC: 4,4'-Butylidene bis(6-tert-butyl-o-cresol)

[0191] PGMEA: Propylene glycol monomethyl ether acetate

[0192] <Preparation of Coloring Compositions No. 1 to 16>

[0193] Using a high-speed blender, each pigment dispersion base liquid and other materials were uniformly mixed according to the ratios in Tables 3 and 4. Then, they were filtered through a filter with a pore size of 3 μm to obtain each coloring composition.

[0194] Table 3

[0195]

[0196] Table 4

[0197]

[0198] The materials used in Tables 3 and 4 are as follows.

[0199] Polymerizable compound: Dipentaerythritol hexaacrylate

[0200] Irgacure 907: Manufactured by Ciba Specialty Chemicals, 2-methyl-[4-(methylthio)phenyl]-2-morpholinopropan-1-one

[0201] The evaluation results of the obtained coloring compositions are shown in Tables 3 and 4. Coloring Compositions No. 1 to 13 and 16 contain coloring materials, dispersants, dispersion media, and specific phosphites. These Coloring Compositions No. 1 to 13 and 16 have good dispersion stability, developability, and development latitude, and the formaldehyde detection amount is reduced to 2 ppm or less. In particular, the dispersion stability of Coloring Compositions No. 1 to 13 containing phenolic antioxidants is more excellent. In addition, the addition times of the phosphites in Coloring Compositions No. 2 and 13 are different. By comparing them, it was found that when the phosphite is added when mixing the coloring material and the dispersant, the formaldehyde detection amount further decreases.

[0202] The present invention includes the following embodiments.

[0203] (Embodiment 1) A coloring composition for a black matrix, characterized in that the coloring composition for a black matrix contains a coloring material, a dispersant, a dispersion medium, and a phosphite, and the phosphite is a compound represented by the general formula (5).

[0204]

[0205] In the general formula (5), R 51represents an alkyl group having 1 to 20 carbon atoms, R 52 and R 53 each independently represent a hydrocarbon group, and R 52 and R 53 may also be bonded to each other to form a cyclic structure. The compound represented by the general formula (5) may also form a dimer or trimer through the bonding of R 52 or R 53 .

[0206] (Embodiment 2) The black matrix coloring composition according to Embodiment 1, wherein the content of the phosphite ester is 0.1 to 100 parts by mass with respect to 100 parts by mass of the dispersant.

[0207] (Embodiment 3) The black matrix coloring composition according to Embodiment 1 or 2, wherein the dispersant is a resinous dispersant having an amine value.

[0208] (Embodiment 4) The black matrix coloring composition according to any one of Embodiments 1 to 3, wherein the coloring composition further contains a phenolic antioxidant.

[0209] (Embodiment 5) The black matrix coloring composition according to Embodiment 4, wherein the phenolic antioxidant is a compound represented by the general formula (6).

[0210]

[0211] In the general formula (6), R 61 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, wherein the carbon atom of R 61 bonded to the benzene ring is a primary to tertiary carbon atom, R 62 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R 63 represents a group in which any one or more carbon atoms of a hydrocarbon group having 2 to 20 carbon atoms are substituted with an ester group or an ether group, or represents a hydrocarbon group having 1 to 20 carbon atoms, and n represents a number from 1 to 6.

[0212] (Embodiment 6) The black matrix coloring composition according to Embodiment 4 or 5, wherein the content of the phenolic antioxidant is 0.1 to 25 parts by mass with respect to 100 parts by mass of the dispersant.

[0213] (Embodiment 7) The black matrix coloring composition according to any one of Embodiments 1 to 6, wherein the coloring composition further contains a binder resin.

[0214] (Embodiment 8) The black matrix coloring composition according to any one of Embodiments 1 to 7, wherein the coloring composition contains a black pigment as a coloring material or contains two or more pigments other than black pigments as a coloring material.

[0215] (Embodiment 9) The coloring composition for a black matrix according to Embodiment 3, wherein the amine value of the dispersant is 10 mgKOH / g to 200 mgKOH / g.

[0216] (Embodiment 10) The coloring composition for a black matrix according to any one of Embodiments 1 to 9, wherein the acid value of the dispersant is less than 20 mgKOH / g.

[0217] (Embodiment 11) The coloring composition for a black matrix according to any one of Embodiments 1 to 10, wherein the total content of the coloring material is 10% by mass to 80% by mass in the total solid content of the coloring composition.

[0218] (Embodiment 12) The coloring composition for a black matrix according to any one of Embodiments 1 to 11, wherein the content of the dispersant is 1 part by mass to 200 parts by mass with respect to 100 parts by mass of the coloring material.

[0219] (Embodiment 13) The coloring composition for a black matrix according to any one of Embodiments 1 to 12, wherein the optical density of the black resist pattern with a film thickness of 1 μm formed from the coloring composition is 0.5 or more.

[0220] (Embodiment 14) A color filter, characterized in that the color filter includes a transparent substrate and a black matrix formed on the transparent substrate, and the black matrix is formed from the coloring composition for a black matrix according to any one of Embodiments 1 to 13.

Claims

1. A coloring composition for a black matrix, characterized in that, The black matrix-forming coloring composition contains a coloring material, a dispersant, a dispersion medium, and a phosphite ester, and the phosphite ester is a compound represented by the general formula (5): In general formula (5), R 51 represents an alkyl group having 1 to 20 carbon atoms, R 52 and R 53 each independently represent an alkyl group having 1 to 20 carbon atoms with or without substituents, or an aromatic group with or without substituents, R 52 and R 53 bond to each other to form a cyclic structure, or do not bond to each other to form a cyclic structure. The compound represented by general formula (5) forms a dimer or trimer through R 52 or R 53 bonding, or does not form a dimer or trimer. The content of the phosphite ester is 0.1 part by mass to 100 parts by mass with respect to 100 parts by mass of the dispersant.

2. The coloring composition for a black matrix according to claim 1, wherein, The phosphite ester is triethyl phosphite, tripropyl phosphite, triisopropyl phosphite, tributyl phosphite, tripentyl phosphite, trihexyl phosphite, trioctyl phosphite, triisooctyl phosphite, trinonyl phosphite, tridecyl phosphite, triisodecyl phosphite, octyl diphenyl phosphite, decyl diphenyl phosphite, diphenyl isodecyl phosphite, tridecyl diphenyl phosphite, hexadecyl diphenyl phosphite, 3,9-bis(octadecyloxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5,5]undecane, or 3,9-bis(isodecyloxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5,5]undecane.

3. The coloring composition for a black matrix according to claim 1, wherein, The dispersant is a resin-type dispersant having an amine value.

4. The coloring composition for a black matrix according to claim 1, wherein, The coloring composition further contains a phenolic antioxidant.

5. The coloring composition for a black matrix according to claim 4, wherein, The phenolic antioxidant is a compound represented by the general formula (6): In general formula (6), R 61 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, wherein the carbon atom of R 61 bonded to the benzene ring is a primary to tertiary carbon atom, R 62 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R 63 represents a group in which any one or more carbon atoms of a hydrocarbon group having 2 to 20 carbon atoms are substituted with an ester group or an ether group, or represents a hydrocarbon group having 1 to 20 carbon atoms, and n represents a number from 1 to 6.

6. The coloring composition for a black matrix according to claim 4, wherein, The content of the phenolic antioxidant is 0.1 part by mass to 25 parts by mass with respect to 100 parts by mass of the dispersant.

7. The coloring composition for a black matrix according to claim 5, wherein, The content of the phenolic antioxidant is 0.5 part by mass to 5 parts by mass, and the content of the phosphite ester is 5 parts by mass to 25 parts by mass with respect to 100 parts by mass of the dispersant.

8. The coloring composition for a black matrix according to claim 1, wherein, The coloring composition further contains a binder resin.

9. The coloring composition for a black matrix according to any one of claims 1 to 8, wherein, The coloring composition contains a black pigment as a coloring material or contains two or more pigments other than black pigments as a coloring material.

10. A color filter, characterized in that, The color filter includes a transparent substrate and a black matrix formed on the transparent substrate, and the black matrix is formed of the black matrix-forming coloring composition according to any one of claims 1 to 9.

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