JP4073463B2 - Method for producing black resist composition for color filter - Google Patents

Description

  The present invention relates to a method for producing a black resist composition suitable for producing a color filter used in combination with a liquid crystal display device or a solid-state imaging device. The black resist composition obtained by the method of the present invention can be suitably used for forming a black pattern serving as a black matrix.

  The color filter is obtained by forming fine pixels such as red, green, and blue on a glass substrate by a dyeing method, a printing method, an electrodeposition method, a pigment dispersion method, or the like. These known methods have the following characteristics and problems. A color filter by a dyeing method is manufactured by forming an image with a photosensitive resin obtained by mixing dichromate as a photosensitizer with gelatin, polyvinyl alcohol, or the like, and then dyeing. In order to form multiple colors on the same substrate, a dye-proofing process is essential, and there is a problem that the process becomes complicated. Moreover, since the dye is used, it is inferior in light resistance. Dichromic acid used as a photosensitizer is also a problem from the viewpoint of pollution prevention.

  The color filter by printing is a method such as screen printing or flexographic printing, which transfers thermosetting or photocurable ink to a glass substrate. Since image formation and dyeing are unnecessary, the process is simple, but a high-definition image cannot be obtained, and there is a problem in the smoothness of the ink. A color filter based on the electrodeposition method is one in which a glass substrate with an electrode is immersed in a bath containing a pigment or dye, and the hue is adhered by electrophoresis. Although it is excellent in smoothness, it is difficult to form a complicated pattern because an electrode is required on the glass substrate in advance.

  In the pigment dispersion method, an image is formed with a colored resist in which a pigment is dispersed in a photocurable resin. There are advantages such as high heat resistance and no need for dyeing, and high-precision image formation is possible. The pigment dispersion method is superior to the above production method in terms of quality and production cost, and is currently the mainstream of color filter production. A grid-like black pattern called a black matrix is generally arranged between the red, blue, and green colored images of the color filter for the purpose of usually improving contrast. Black matrix is generally formed by depositing chromium on the entire glass substrate and patterning it by etching. However, because it uses chromium, it has high cost and high reflectivity, and has a problem in waste liquid treatment. Yes. For this reason, studies for producing a black matrix by a pigment dispersion method capable of fine processing have been intensively conducted.

  A black resist for forming a black matrix is a photosensitive composition in which a black pigment or several kinds of pigments are mixed to be black. Since the black resist is intended for light shielding, it is a composition containing a large amount of a pigment insoluble in the developer. For this reason, the black resist has poor developability, and there are problems such as long-time development and the required resolution cannot be obtained.

  In conventional black resists, developability is significantly hindered by the large amount of black pigment contained, and in extreme cases, the non-image area is insoluble in the developer or the resolution is insufficient even if development is possible And formation of a black matrix was extremely difficult. When the solubility in the developing solution is low, it is necessary to extend the developing time or use a developing solution having a strong dissolving power. If the development time is extended, the productivity is lowered, and a developing solution having a strong solubility also erodes the image area, which causes problems such as a decrease in resolution and adhesion. An object of the present invention is to solve the above-mentioned problems of the conventional black resist and to provide a method for producing a composition capable of producing a color filter with high developability and high resolution.

  As a result of diligent research, the present inventors have used carbon black as a black pigment and mixed it with a binder resin, a photopolymerization initiator, and a monomer that is cured by the action of the photopolymerization initiator to produce light for a color filter. In the case of producing a curable black resist composition, if carbon black that has been adsorbed with 20 to 200 mg / g of resin in advance by dispersion treatment with a resin in a solvent is used, high developability and high The inventors have found that a high-quality color filter can be produced with a resolution, and have reached the present invention.

  According to the present invention, it is possible to produce a high-quality color filter with high developability and high resolution by preliminarily dispersing carbon black with a resin so that the resin adsorption amount is 20 to 200 mg / g. A photocurable black resist composition for a color filter can be obtained.

The photocurable black resist composition for a color filter produced by the method of the present invention includes, as essential components, carbon black, a binder resin, a photopolymerization initiator, a monomer and a solvent that are cured by the action of the photopolymerization initiator. Contains.
The binder resin is not particularly limited as long as it is a polymer compound capable of forming a coating film, and specific examples include the following compounds.
1) Polyolefin polymers Polyethylene, polypropylene, polyisobutylene, etc. 2) Diene polymers, polybutadiene, polyisoprene, etc. 3) Polymers having conjugated polyene structure Polyacetylene polymers, polyphenylene polymers, etc. 4) Vinyl polymers Polyvinyl chloride, polystyrene, polyacetic acid Vinyl, polyvinyl alcohol, polyacrylic acid, polyacrylic acid ester, polyacrylamide, polyacrylonitrile, polyvinylphenol, etc. 5) Polyether Polyphenylene ether, Polyoxirane, Polyoxetane, Polytetrahydrofuran, Polyetherketone, Polyetheretherketone, Polyacetal, etc. 6) Phenol resin, novolak resin, resole resin, etc. 7) Polyester, polyethylene terephthalate, Polyphenolphthalein terephthalate, polycarbonate, alkyd resin, unsaturated polyester resin, etc. 8) Polyamide, nylon-6, nylon 66, water-soluble nylon, polyphenyleneamide, etc. 9) Polypeptide gelatin, casein, etc. 10) Epoxy resin and its modified products, novolak epoxy Resin, modified resin with bisphenol epoxy resin, novolac epoxy acrylate and acid anhydride, etc. 11) Others Polyurethane, polyimide, melamine resin, urea resin, polyimidazole, polyoxazole, polypyrrole, polyaniline, polysulfide, polysulfone, celluloses, etc.

  Among these resins, those having a carboxyl group or a phenolic hydroxyl group in the resin side chain or main chain can be alkali-developed, which is preferable from the viewpoint of pollution prevention. In particular, a resin having a carboxyl group, for example, an acrylic acid (co) polymer, a styrene / maleic anhydride resin, an acid anhydride-modified resin of novolak epoxy acrylate, and the like are preferable because of high alkali developability. Furthermore, an acrylic resin is preferable because it is excellent in developability, and a copolymer thereof is more preferable from the viewpoint of performance and production control because various monomers can be selected and polymerized.

  More specifically, the acrylic resin containing a carboxyl group is, for example, a monomer having a carboxyl group such as (meth) acrylic acid, (anhydrous) maleic acid, crotonic acid, itaconic acid, fumaric acid, styrene, α-methyl, etc. Styrene, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, vinyl acetate, acrylonitrile, (meth) acrylamide, glycidyl (meth) ) Acrylate, allyl glycidyl ether, glycidyl ethyl acrylate, glycidyl crotonic acid ether, (meth) acrylic acid chloride, benzyl (meth) acrylate, hydroxyethyl (meth) acrylate, N-methylol acrylamide, N, N dimethylacrylamid , N- methacryloyl morpholine, N, N- dimethylaminoethyl (meth) acrylate, N, N- dimethylaminoethyl acrylamide, polymers obtained by copolymerizing comonomers such. Among them, an acrylic resin containing at least (meth) acrylic acid or (meth) acrylic acid alkyl ether as a constituent monomer is preferable, and an acrylic resin containing (meth) acrylic acid and styrene is more preferable.

  Moreover, these resins can also add an ethylenic double bond to the resin side chain. Since the photocurability is increased by imparting a double bond to the resin side chain, the resolution and adhesion can be further improved, which is preferable. Examples of the synthesis means for introducing an ethylenic double bond include the methods described in JP-B-50-34443 and JP-B-50-34444. Specific examples include a method of reacting a compound having both a glycidyl group, an epoxycyclohexyl group and a (meth) acryloyl group with a carboxyl group or a hydroxyl group, or acrylic acid chloride. For example, glycidyl (meth) acrylate, allyl glycidyl ether, glycidyl α-ethyl acrylate, crotonyl glycidyl ether, (iso) crotonic acid glycidyl ether, (3,4-epoxycyclohexyl) methyl (meth) acrylate, (meth) By using a compound such as acrylic acid chloride or (meth) allyl chloride and reacting with a resin having a carboxyl group or a hydroxyl group, a resin having a polymer group in the side chain can be obtained. In particular, a resin obtained by reacting (3,4-epoxycyclohexyl) methyl (meth) acrylate is preferable. In this specification, “(meth) acryl-”, “(meth) acrylate” and the like mean “acryl- or methacryl-”, “acrylate or methacrylate”, and the like, for example, “(meth) acryl” "Acid" shall mean "acrylic acid or methacrylic acid".

  The preferable range of the weight average molecular weight measured by GPC of these acrylic resins is 1000 to 100,000, and if it exceeds this, the developability tends to decrease. Moreover, the range of preferable content of a carboxyl group is 5-200 in an acid value. When the acid value is 5 or less, it becomes insoluble in an alkaline developer, and when it exceeds 200, the sensitivity may be lowered.

  As the monomer cured by the action of the photopolymerization initiator, any known monomer such as a monomer that undergoes radical polymerization by the action of a radical generated by the photopolymerization initiator and a monomer that undergoes addition condensation by the action of an acid generated from the photopolymerization initiator. Can also be used. Typical examples of the former include monomers having an ethylenic double bond, and more specifically, isobutyl acrylate, t-butyl acrylate, lauryl acrylate, cetyl acrylate, stearyl acrylate, cyclohexyl acrylate, isobornyl acrylate, Benzyl acrylate, 2-methoxyethyl acrylate, 3-methoxybutyl acrylate, ethyl carbitol acrylate, phenoxyethyl acrylate, tetrahydrofuryl acrylate, phenoxy polyethylene glycol acrylate, methoxypropylene glycol acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-acryloyloxyethyl hydrogen phthalate, 2-acryloyloxyp Pyrhydrogen phthalate, 2-acryloyloxypropyl tetrahydro phthalate, morpholinoethyl methacrylate, trifluoroethyl acrylate, trifluoroethyl methacrylate, tetrafluoropropyl (meth) acrylate, hexafluoropropyl (meth) acrylate, octafluoropentyl (meth) acrylate , Heptadecafluorododecyl acrylate, trimethylsiloxyethyl methacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, neopentyl glycol diacrylate, tetraethylene glycol diacrylate , Tripropylene glycol diacrylate, propylene glycol diac Rate, glycerin methacrylate acrylate, bisphenol A ethylene oxide adduct diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, trimethylolpropane ethylene oxide adduct triacrylate, glycerin propylene oxide adduct triacrylate, tris Acryloyloxyethyl phosphate, dipentaerythritol hexaacrylate, modified acrylic acid of novolac epoxy, modified acrylic acid and anhydride of novolac epoxy, N-vinylpyrrolidone, N-vinylcaprolactam, acrylated isocyanurate, dipenta Erythritol monohydroxypentaacrylate, urethane acrylate And unsaturated polyester acrylates. Among these monomers, acrylic monomers, particularly acrylic monomers having 3 or more double bonds are preferable. These monomers are used alone or in combination. On the other hand, as a monomer which undergoes addition condensation by the action of an acid generated from a photopolymerization initiator, melamine, benzoguanamine, glycoluril or urea is a compound obtained by acting formaldehyde or an alkyl-modified compound thereof, an epoxy compound or a resole compound. Examples thereof include compounds having an action.

  Specifically, Mitsui Cyanamid's Cymel (registered trademark) 300, 301, 303, 350, 736, 738, 370, 771, 325, 327, 703, 701, 266, 267, 285, 232, 235, 238, 1141, 272, 254, 202, 1156, 1158 are examples of compounds in which formaldehyde is allowed to act on melamine or alkyl modified products thereof. Cymel (registered trademark) 1123, 1125, and 1128 are examples of a compound obtained by allowing formaldehyde to act on benzoguanamine or an alkyl-modified product thereof. Cymel (registered trademark) 1170, 1171, 1174, and 1172 are examples of compounds obtained by allowing formaldehyde to act on glycoluril or alkyl-modified products thereof. UFR (registered trademark) 65, 300 of Mitsui Cyanamid Co., Ltd. can be given as an example of a compound obtained by reacting urea with formaldehyde or an alkyl modified product thereof.

  Examples of epoxy compounds include triglycidyl trishydroxyethyl isocyanurate, allyl glycidyl ether, ethylhexyl glycidyl ether, phenyl glycidyl ether, phenol glycidyl ether, lauryl alcohol glycidyl ether, adipic acid glycidyl ether, phthalic acid glycidyl ether, dibromophenyl glycidyl ether, Dibromoneopentyl glycol diglycidyl ether, glycidyl phthalimide, (poly) ethylene glycol glycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, glycerin polyglycidyl ether, trimethylolpropane polyglycidyl ether, butyl glycidyl ether, etc. It is possible .

Among these, particularly preferred compounds include compounds having a —N (CH ₂ OR) ₂ group in the molecule (wherein R represents a hydrogen atom or an alkyl group). Specifically, a compound obtained by reacting formaldehyde with urea or melamine or an alkyl-modified product thereof is particularly preferable. Examples of the resol compound include PP-3000s, PP-3000A, RP-2978, SP-1974, SP-1975, SP-1976, SP-1977, and RP-3972 manufactured by Gunei Chemical Co., Ltd.

  Among these binder resins and monomers, the combination of the above acrylic resin containing a carboxyl group and an acrylic monomer is most preferable in terms of developability. As the photopolymerization initiator, any known photopolymerization initiator can be used, and examples thereof include a compound capable of generating a radical for polymerizing an ethylenically unsaturated group by ultraviolet rays and a compound capable of generating an acid by ultraviolet rays.

  Specifically, 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (4-methoxynaphthyl) -4,6-bis (trichloromethyl) -s-triazine, Halomethyl such as 2- (4-ethoxynaphthyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (4-ethoxycarbonylnaphthyl) -4,6-bis (trichloromethyl) -s-triazine Triazine derivatives, halomethylated oxazole derivatives, 2- (2'-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (2'-chlorophenyl) -4,5-bis (3'-methoxyphenyl) imidazole Dimer, 2- (2'-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (2'-methoxyphenyl)- , 5-diphenylimidazole dimer, imidazole derivatives such as (4′-methoxyphenyl) -4,5-diphenylimidazole dimer, benzoin such as benzoin methyl ether, benzoin phenyl ether, benzoin isobutyl ether, benzoin isopropyl ether, Benzoin alkyl ethers, 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, anthraquinone derivatives such as 1-chloroanthraquinone, benzanthrone derivatives, benzophenone, 4,4'-bis (dimethylamino) benzophenone (Michler's ketone) ), 4,4'-bis (diethylamine) benzophenone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methylbenzophenone, 2-chloro Benzophenone derivatives such as benzophenone, 4-bromobenzophenone, 2-carboxybenzophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, α-hydroxy-2-methylphenyl Propanone, 1-hydroxy-1-methylethyl- (p-isopropylphenyl) ketone, 1-hydroxy-1- (p-dodecylphenyl) ketone, 2-methyl- (4 ′-(methylthio) phenyl) -2- Acetophenone derivatives such as morpholino-1-propanone, 1,1,1-trichloromethyl- (p-butylphenyl) ketone, thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-di Thiolxanthone derivatives such as tilthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, benzoic acid ester derivatives such as ethyl p-dimethylaminobenzoate, ethyl p-diethylaminobenzoate, 9-phenylacridine, 9- ( acridine derivatives such as p-methoxyphenyl) acridine, phenazine derivatives such as 9,10-dimethylbenzphenazine, di-cyclopentadienyl-Ti-di-chloride, di-cyclopentadienyl-Ti-bis-phenyl, di -Cyclopentadienyl-Ti-bis-2,3,4,5,6-pentafluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,3,5,6-tetrafluorophenyl -1-yl, di-cyclopentadienyl-Ti-bi -2,4,6-trifluorophen-1-yl, di-cyclopentadienyl-Ti-2,6-di-fluorophen-1-yl, di-cyclopentadienyl-Ti-2,4- Di-fluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2,3,4,5,6-pentafluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis -Titanocene derivatives such as 2,6-di-fluorophen-1-yl, di-cyclopentadienyl-Ti-2,6-di-fluoro-3- (pyr-1-yl) -phen-1-yl Etc. These photopolymerization initiators are used alone or in combination. For example, combinations of initiators described in JP-B-53-12802, JP-A-1-279903, JP-A-2-48664, JP-A-4-164902, JP-A-6-75373 and the like can be mentioned.

  The carbon black used in the present invention is specifically carbon black # 2400, # 2350, # 2300, # 2200, # 1000, # 980, # 970, # 960, # 950, # 900, # 900 manufactured by Mitsubishi Chemical Corporation. 850, MCF88, # 650, MA600, MA7, MA8, MA11, MA100, MA220, IL30B, IL31B, IL7B, IL11B, IL52B, # 4000, # 4010, # 55, # 52, # 50, # 47, # 45, # 44, # 40, # 33, # 32, # 30, # 20, # 10, # 5, CF9, # 3050, # 3150, # 3250, # 3750, # 3950, Diamond Black A, Diamond Black N220M, Diamond Black N234, Diamond Black I, Diamond Black LI, Diamond Black II, Diab N339, diamond black SH, diamond black SHA, diamond black LH, diamond black H, diamond black HA, diamond black SF, diamond black N550M, diamond black E, diamond black G, diamond black R, diamond black N760M, diamond black LP. Carbon black thermax N990, N991, N907, N908 made by Cancarb. Carbon black Asahi # 80, Asahi # 70, Asahi # 70L, Asahi F-200, Asahi # 66, Asahi # 66HN, Asahi # 60H, Asahi # 60U, Asahi # 60, Asahi # 55, Asahi # 50H, Asahi # 51, Asahi # 50U, Asahi # 50, Asahi # 35, Asahi # 15, Asahi Thermal, Degussa's carbon black ColorBlack Fw200, ColorBlack Fw2, ColorBlack Fw2, ColorBlack Fw1, ColorBlack 170, BlackBlack, BlackBlack S160, SpecialBlack6, SpecialBlack5, SpecialBlack4, SpecialBlack4A, PrintexU, PrintexV, Printex140U, Printex140 Etc. The.

  Since these carbon blacks are aggregated as they are, they are used after being subjected to a dispersion treatment in advance in the present invention. In the dispersion treatment, a resin and a solvent are added to carbon black to form a mill base, which is subjected to dispersion treatment by a method such as a ball mill, sand mill, bead mill, three rolls, paint shaker, ultrasonic wave, bubble homogenizer or the like. Two or more of these processing methods can be combined. As a resin used for dispersion, a binder resin of a resist composition is used as it is, Anti-Terra-U, Disperbyk-160, 161, 162, 163 manufactured by BYK, Solspers 20000, 24000GR, 26000, 28000, manufactured by ZENECA Kasei DA-703-50, NDC-8194L, NDC-8203L, NDC-8257L, KS-860, Kao's homogenal L-18, L-1820, L-95, L-100, Nippon Paint Known dispersion resins such as VP5000 manufactured by Goodrich, E5703P manufactured by Goodrich, VAGH manufactured by Union Carbide, UR8200 manufactured by Toyobo, and MR113 manufactured by ZEON can be used. These resins can be used alone or in combination. Among these resins, the acrylic resin containing the carboxyl group is preferable. The resin is adsorbed on the surface of the carbon black by the dispersion treatment, and at the same time, the aggregation of the carbon black particles is broken and the particle size is refined. The preferable average particle diameter of carbon black is in the range of 0.01 to 1 μm. In the present invention, the resin adsorbed on the surface of carbon black needs to be in the range of 1 to 200 mg / g in terms of resin adsorption. More preferably, it is 5-180 mg / g. More preferably, it is 20-160 mg / g. When the resin adsorption amount exceeds the upper limit of the above range, the developability and resolution are deteriorated. Also, below the lower limit, dispersion is not stabilized and reaggregation occurs in a short period of time. The resin adsorption amount can be determined from the difference from the charged amount by ultracentrifuging the carbon black dispersion and determining the resin concentration of the supernatant by a gravimetric method.

  More specifically, a paste in which carbon black is dispersed in a resin is diluted 10 times with propylene glycol monomethyl ether acetate, treated with ultrasonic waves using BRANSON 5200 manufactured by Nippon Emerson Co., Ltd., and then 1 at 27000 rpm. Ultracentrifugation is carried out for a period of time, and the supernatant is dried at 120 ° C. for 2 hours.

  Specific examples of the solvent include diisopropyl ether, mineral spirit, n-pentane, amyl ether, ethyl caprylate, n-hexane, diethyl ether, isoprene, ethyl isobutyl ether, butyl stearate, n-octane, valsol # 2, and apco. # 18 Solvent, diisobutylene, amyl acetate, butyl butyrate, apcocinner, butyl ether, diisobutyl ketone, methylcyclohexene, methyl nonyl ketone, propyl ether, dodecane, Social solvent No. 1 and no. 2, amyl formate, dihexyl ether, diisopropyl ketone, Solvesso # 150, (n, sec, t) -butyl acetate, hexene, shell, TS28, solvent, butyl chloride, ethyl amyl ketone, ethyl benzoate, amyl chloride, ethylene Glycol diethyl ether, ethyl orthoformate, methoxymethyl pentanone, methyl butyl ketone, methyl hexyl ketone, methyl isobutyrate, benzonitrile, ethyl propionate, methyl cellosolve acetate, methyl isoamyl ketone, methyl isobutyl ketone, propyl acetate, Amyl acetate, amyl formate, bicyclohexyl, diethylene glycol monoethyl ether acetate, dipentene, methoxymethylpentanol, methyl Milketone, methyl isopropyl ketone, propyl propionate, propylene glycol-t-butyl ether, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, ethyl cellosolve acetate, carbitol, cyclohexanone, ethyl acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether Acetate, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monomethyl ether acetate, 3-methoxypropionic acid, 3-ethoxypropionic acid, 3-ethoxy Ethyl propionate, 3-methoxy Methyl propionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, dipropylene glycol monomethyl ether, ethylene glycol acetate, ethyl carbitol, butyl carbitol, ethylene glycol monobutyl ether, Examples thereof include organic solvents such as propylene glycol-t-butyl ether, 3-methyl-3-methoxybutanol, tripropylene glycol methyl ether, 3-methyl-3-methoxybutyl acetate. It is preferable to select a solvent having a boiling point in the range of 100 ° C to 200 ° C. More preferably, it has a boiling point of 120 ° C to 170 ° C. These solvents are used alone or in combination.

  In the black resist composition, the monomer is 5 to 80 parts by weight, the photopolymerization initiator is 0.01 to 30 parts by weight, the carbon black is 100 to 500 parts by weight, and the solvent is 200 parts by weight with respect to 100 parts by weight of the binder resin. It is preferable to make it contain in the range of -10000 weight part. If the monomer is less than the above range, the image-exposed image area has insufficient crosslinking density, and it is difficult to obtain a good image, and if it exceeds the above range, the resist film after drying becomes more sticky, resulting in workability. May become inferior. If the addition amount of the photopolymerization initiator is less than the above range, sufficient sensitivity cannot be obtained, and if it exceeds the above range, the initiator sometimes precipitates from the photosensitive solution. If the added amount of carbon black is less than the above range, it is difficult to obtain a sufficient color density and the light shielding ability is poor, and if it exceeds the above range, the dispersion stability of the pigment cannot be maintained. A film may not be obtained. If the amount of the solvent added is less than the above range, uneven coating tends to occur and the film thickness is not uniform.If the amount exceeds the above range, a sufficient film thickness cannot be obtained, and coating defects such as pinholes may occur. May be easier. In addition, it is preferable that the density | concentration in the total solid of carbon black is 25 to 70 weight%. In addition to the above components, a sensitizer, a coating property improver, a polymerization inhibitor, a plasticizer, a flame retardant, and the like can be suitably added to the black resist composition. These can be used alone or in combination of several kinds.

  The black resist composition obtained by the present invention is applied to a glass substrate by a known method such as a spin coater, a roll coater, a curtain coater, or screen printing. The coating film thickness is preferably 0.1 μm to 10 μm. A convection oven or a hot plate is used to dry the coating film. The drying temperature is preferably 50 ° C. to 150 ° C., and the drying time is preferably 30 seconds to 60 minutes. For the exposure, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a xenon lamp, a carbon arc lamp or the like is generally used, and a latent image is formed on the resist film by exposing through a mask. Then, an image is formed by developing with the solvent which dissolves an unexposed part. As the developer, an organic solvent such as acetone, toluene, or MEK can be used, but an alkali developer is preferable from the viewpoint of environmental problems. For example, sodium hydroxide aqueous solution, potassium hydroxide aqueous solution, sodium carbonate aqueous solution, potassium carbonate, ammonia water, tetramethylammonium hydroxide aqueous solution and the like are used. A surfactant, an antifoaming agent, or the like may be added to the alkaline developer. There is no restriction | limiting in particular as a developing method, It can carry out by well-known methods, such as a paddle method, a dipping method, and a spray method. A pre-wet may be adopted. Post-baking, post-photocuring, etc. may be employed for the purpose of enhancing the drying of the developer after the image formation and the curing of the resist film.

Next, although it demonstrates concretely using an Example, this invention is not limited to a following example, unless the summary is exceeded.
Synthesis Example-1
A flask was charged with 20 g of a styrene / acrylic acid resin having an acid value of 200 and a weight average molecular weight of 5000, 0.2 g of p-methoxyphenol, 0.2 g of dodecyltrimethylammonium chloride, and 40 g of propylene glycol monomethyl ether acetate (3,4 epoxy cyclohexyl) methyl. 7.6 g of acrylate was added dropwise and reacted at a temperature of 100 ° C. for 30 hours. The reaction solution was reprecipitated in water and dried to obtain a resin. When neutralization titration with KOH was performed, the acid value of the resin was 80.

Dispersion of carbon black 100 g of carbon black (manufactured by Mitsubishi Chemical Corporation, MA220) was mixed with 100 g of the resin varnish of Synthesis Example-1 and 100 g of propylene glycol mol-methyl ether acetate, and a mill base was prepared. This was processed by a bead mill. The beads used a particle size of 0.5 mm and the material zirconia. Carbon black pastes with different amounts of resin adsorption were prepared by changing the disk peripheral speed and dispersion time at a dispersion temperature of about 60 ° C.

Measurement of resin adsorption amount A part of the carbon black paste was collected, diluted 10-fold with propylene glycol monomethyl ether acetate, and treated with ultrasonic waves using BRANSON 5200 manufactured by Nippon Emerson Co., Ltd. for 3 minutes. This sample was subjected to ultracentrifugation (27000 rpm, 1 hour), and a supernatant was taken. After the supernatant was dried at 120 ° C. for 2 hours, the resin weight was determined by a precision balance, and the amount of resin adsorbed on the carbon black was calculated from the difference from the charged amount.

Black resist formulation 1) Carbon black paste: 40g
2) Dipentaerythritol hexaacrylate: 5g
3) Dicyclopentadienyl-Ti-bis-2,6-difluoro-3- (pyrrole-1
-Yl) -phenyl-1-yl: 0.5 g
4) 4,4'-bis (diethylamino) benzophenone: 0.5 g
5) Propylene glycol monomethyl ether acetate: 30 g
The black resist photosensitive solution was prepared by mixing at the above ratio.

Evaluation of Resist A black resist photosensitive solution was applied to a glass substrate with a spin coater and dried on a hot plate at 80 ° C. for 1 minute. The resist film thickness after drying was 1 μm. This sample was exposed to 2000 mj / cm ² image with a high-pressure mercury lamp through a mask. A resist pattern was obtained by immersion development in a potassium hydroxide aqueous solution having a temperature of 25 ° C. and a concentration of 0.05%. The development speed was determined by visually observing the time during which the non-image area was developed. In addition, the minimum resist pattern that can be formed was observed with a microscope to determine the resolving power.

Claims (10)

A method for producing a photo-curable black resist composition for a color filter comprising a carbon black, a binder resin, a photopolymerization initiator, a monomer that cures by the action of a photopolymerization initiator, and a solvent. A carbon black paste that is dispersed with resin and adsorbed with 20 to 200 mg / g of resin as measured by the following method is used.
Measuring method of resin adsorption:
A paste obtained by dispersing carbon black with a resin is diluted 10 times with propylene glycol monomethyl ether acetate. The obtained dispersion is treated with ultrasound for 3 minutes and then ultracentrifuged for 1 hour. The resin concentration of the supernatant liquid is obtained by a weight method, and the adsorption amount of the resin per 1 g of carbon black is calculated from the difference between the weight of the carbon black and the resin used for the dispersion treatment and the amount of resin in the supernatant liquid. A method for producing a photocurable black resist composition for a color filter comprising a carbon black, a binder resin, a photopolymerization initiator, a monomer that cures by the action of a photopolymerization initiator, and a solvent, wherein the carbon black is dissolved in the solvent. It is characterized in that a carbon black paste in which 20 to 200 mg / g of resin is adsorbed is measured by the following method after being dispersed with the resin, and a monomer that is cured by the action of a photopolymerization initiator is mixed therewith. how to.
Measuring method of resin adsorption:
A paste obtained by dispersing carbon black with a resin is diluted 10 times with propylene glycol monomethyl ether acetate. The obtained dispersion is treated with ultrasound for 3 minutes and then ultracentrifuged for 1 hour. The resin concentration of the supernatant liquid is obtained by a weight method, and the adsorption amount of the resin per 1 g of carbon black is calculated from the difference between the weight of the carbon black and the resin used for the dispersion treatment and the amount of resin in the supernatant liquid.   The method according to claim 1 or 2, wherein the resin adsorption amount of carbon black is 40 to 160 mg / g.   4. The method according to claim 1, wherein the resin using a carbon black dispersion treatment is a binder resin.   The method according to any one of claims 1 to 4, wherein the binder resin is an acrylic resin having a carboxyl group.   The method according to claim 5, wherein the acrylic resin contains styrene and (meth) acrylic acid as constituent monomers.   The method according to claim 5 or 6, wherein the acrylic resin has an ethylenic double bond in the resin side chain.   The method according to any one of claims 1 to 7, wherein the monomer cured by the action of the photopolymerization initiator is an acrylic monomer.   The method according to any one of claims 1 to 4, wherein the binder resin is an acrylic resin having a carboxyl group, and the monomer cured by the action of the photopolymerization initiator is an acrylic monomer.   100 to 500 parts by weight of carbon black, 0.01 to 30 parts by weight of a photopolymerization initiator, 5 to 80 parts by weight of a monomer that is cured by the action of the photopolymerization initiator, and 200 parts of a solvent with respect to 100 parts by weight of the binder resin. The method according to any one of claims 1 to 9, wherein these are blended so as to be 10000 parts by weight.