Photosensitive resin composition, display device and forming method of pattern

Abstract

A photosensitive resin composition is provided that can realize a cured film having high hardness and forming a net taper when a pattern is formed in a low-temperature curing process. One embodiment of the present invention provides a photosensitive resin composition comprising 100 parts by weight of an alkali-soluble resin, 2 to 40 parts by weight of an initiator, 2 to 100 parts by weight of a polyfunctional compound, more than 1 part by weight and less than or equal to 30 parts by weight of a plasticizer, and more than 0 parts by weight and less than or equal to 15 parts by weight of an epoxy-based additive.

Description

Technology Field

[0001] The present invention relates to a photosensitive resin composition, a display device, and a pattern forming method, and more specifically, to a photosensitive resin composition, a display device, and a pattern forming method capable of forming a net taper and realizing a high-hardness cured film when forming a pattern in a low-temperature curing process. Background Technology

[0002] The display industry is broadly divided into LCD (liquid crystal display) and OLED (organic light-emitting diode), and recently, there has been high interest in OLED-based flexible displays.

[0003] Following Korea, companies in China, Taiwan, and Japan are also competitively attempting to expand their flexible display businesses. By adding flexibility to rigid displays, rollable and foldable designs have become possible, enabling the application of displays for various uses.

[0004] In particular, since a low-temperature curing process is unavoidable for OLED (organic light-emitting diode) displays, materials such as photosensitive resin compositions applied to displays also require properties at low temperatures. However, it is generally known that a stable cured film can be obtained by undergoing a post-curing process at 150 to 300°C for photosensitive resin compositions. Consequently, there has been a problem in applying a curing step of 150°C or higher to devices based on flexible materials that have low heat resistance performance of around 100 to 130°C. The problem to be solved

[0005] The object of the present invention is to provide a photosensitive resin composition having a high hardness and forming a net taper when a pattern is formed during a low-temperature curing process.

[0006] Another objective of the present invention is to provide a photosensitive resin composition that has excellent planarization performance of the pattern film and excellent adhesion to the substrate.

[0007] Another objective of the present invention is to provide a display device comprising a cured film made of the photosensitive resin composition.

[0008] Another objective of the present invention is to provide a pattern forming method applicable to the display device.

[0009] The objects of the present invention are not limited to those mentioned above, and other unmentioned objects and advantages of the present invention may be understood from the following description and will be more clearly understood by the embodiments of the present invention. Furthermore, it will be readily apparent that the objects and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims. means of solving the problem

[0010] One embodiment of the present invention for achieving the above objective provides a photosensitive resin composition comprising 100 parts by weight of an alkali-soluble resin, 2 to 40 parts by weight of an initiator, 2 to 100 parts by weight of a polyfunctional compound, more than 1 and less than 30 parts by weight of a plasticizer, and more than 0 and less than 15 parts by weight of an epoxy-based additive. Specifically, based on 100 parts by weight of the alkali-soluble resin, the content of the plasticizer may be more than 1 and less than 11 parts by weight, and the content of the epoxy-based additive may be more than 0 and less than 7 parts by weight.

[0011] Another embodiment of the present invention for achieving the above objective may provide a display device comprising a cured film made of the photosensitive resin composition.

[0012] Another embodiment of the present invention for achieving the above objective may provide a pattern forming method comprising: (S1) a step of forming a coating film by applying a photosensitive resin composition according to claim 1 onto a substrate; (S2) a step of selectively exposing the coating film and then removing the unexposed coating film with a developer; and (S3) a step of curing the exposed coating film, wherein step (S3) is performed at 80 to 150°C.

[0013] The means for solving the above problem do not enumerate all the features of the present invention. Various features of the present invention and the resulting advantages and effects can be understood in more detail by referring to the specific embodiments below. Effects of the invention

[0014] According to one embodiment of the present invention, a photosensitive resin composition can be provided that forms a net taper during pattern formation in a low-temperature curing process, has excellent planarization performance of the pattern film, and has excellent adhesion to a substrate. By using such a photosensitive resin composition to form a pattern film of high hardness on a substrate of a flexible display, excellent pattern characteristics can be realized.

[0015] In addition to the effects described above, the specific effects of the present invention are described together with the following explanation of the specific details for implementing the invention. Specific details for implementing the invention

[0016] Hereinafter, each component of the present invention is described in more detail so that a person skilled in the art to which the present invention pertains can easily implement it; however, this is merely an example, and the scope of the rights of the present invention is not limited by the following.

[0017] One embodiment of the present invention provides a photosensitive resin composition comprising 100 parts by weight of an alkali-soluble resin, 2 to 40 parts by weight of an initiator, 2 to 100 parts by weight of a polyfunctional compound, more than 1 part by weight and less than or equal to 30 parts by weight of a plasticizer, and more than 0 part by weight and less than or equal to 15 parts by weight of an epoxy-based additive.

[0018] The configuration of the present invention will be described in more detail below.

[0019] 1. Photosensitive resin composition

[0020] The photosensitive resin composition according to the present invention comprises an alkali-soluble resin that can impart solubility to a developer used in a developing process when forming a pattern and performs a binder function.

[0021] An alkali-soluble resin according to one embodiment of the present invention may be a copolymer having one selected from the group consisting of unsaturated carboxylic acids, unsaturated carboxylic acid anhydrides, and mixtures thereof as a monomer.

[0022] The above unsaturated carboxylic acid may be, for example, any one selected from the group consisting of methacrylic acid, acrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, and vinylacetic acid and mixtures thereof.

[0023] The above unsaturated carboxylic acid anhydride may be, for example, produced by the reaction of one or two molecules selected from the above unsaturated carboxylic acid.

[0024] Specifically, based on 100 parts by weight of the total copolymerization monomers participating in the copolymerization reaction for synthesizing the alkali-soluble resin, any monomer selected from the group consisting of unsaturated carboxylic acids, unsaturated carboxylic acid anhydrides, and mixtures thereof may be copolymerized in an amount of 10 to 60 parts by weight, specifically 20 to 50 parts by weight, and more specifically 30 to 40 parts by weight. If the content of the unsaturated carboxylic acid, unsaturated carboxylic acid anhydride, or mixture thereof is less than the above numerical range, a problem may arise where it is difficult to dissolve in an alkaline aqueous solution, and if it exceeds the above numerical range, a problem may arise where the solubility in an alkaline aqueous solution becomes excessively high.

[0025] An alkali-soluble resin according to another embodiment of the present invention may be a copolymer comprising an olefinic unsaturated compound as a monomer.

[0026] The above olefinic unsaturated compounds are, for example, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, methyl acrylate, isopropyl acrylate, cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, dicyclopentenyl acrylate, dicyclopentenyl acrylate, dicyclopentenyl methacrylate, dicyclopentenyl methacrylate, 1-adamantyl acrylate, 1-adamantyl methacrylate, dicyclopentanyl oxyethyl methacrylate, isoboronyl methacrylate, cyclohexyl acrylate, 2-methylcyclohexyl acrylate, dicyclopentanyl oxyethyl acrylate, isoboronyl acrylate, phenyl methacrylate, Phenyl acrylate, Benzyl methacrylate, Benzyl acrylate, 2-Hydroxyethyl methacrylate, Styrene, σ-Methyl styrene, m-Methyl styrene, p-Methyl styrene, Vinyltoluene, p-Methoxystyrene, 1,3-Butadiene, Isoprene, 2,3-Dimethyl 1,3-Butadiene, Glycidyl acrylate, Glycidyl methacrylate, α-Ethylacrylate Glycidyl, α-n-Propylic acid Glycidyl, α-n-Butylacrylate Glycidyl, β-Methylglycidyl Acrylate, β-Methylglycidyl Methacrylate, β-Ethylglycidyl Acrylate, β-Ethylglycidyl Methacrylate, 3,4-Epoxybutyl Acrylate, 3,4-Epoxybutyl Methacrylate, It may be any one selected from the group consisting of acrylic acid-6,7-epoxyheptyl, methacrylic acid-6,7-epoxyheptyl, α-ethylacrylic acid-6,7-epoxyheptyl, o-vinylbenzylglycidyl ether, m-vinylbenzylglycidyl ether, p-vinylbenzylglycidyl ether, methacrylic acid 3,4-epoxycyclohexyl, and combinations thereof.

[0027] Based on 100 parts by weight of the total copolymer monomers participating in the copolymerization reaction of the alkali-soluble resin, the content of the olefin-based unsaturated compound may be 60 to 95 parts by weight, specifically 60 to 80 parts by weight, and more specifically 60 to 70 parts by weight. If the content of the olefin-based unsaturated compound is below the above numerical range, a problem may arise in which the resolution or heat resistance is reduced, and if it exceeds the above numerical range, a problem may arise in which the alkali-soluble resin becomes difficult to dissolve in the alkaline aqueous solution that is the developer.

[0028] According to one embodiment of the present invention, the weight-average molecular weight of the alkali-soluble resin in terms of polystyrene may be 2,000 to 20,000 g / mol, specifically 2,000 to 10,000 g / mol, and more specifically 3,000 to 7,000 g / mol. If the weight-average molecular weight of the alkali-soluble resin is below the above numerical range, problems may arise such as reduced pattern developability, residual film rate, and heat resistance performance, and if it exceeds the above numerical range, problems may arise such as failure to develop the pattern.

[0029] In this specification, the term 'acrylic compound' is defined to encompass both unsaturated carboxylic acids and unsaturated esters. For example, the unsaturated carboxylic acid may be acrylic acid, methacrylic acid, etc., and the unsaturated ester may be methyl methacrylate, benzyl methacrylate, etc.

[0030] According to another embodiment of the present invention, the alkali-soluble resin may be a copolymer comprising an acrylic compound as a monomer. The glass transition temperature of the homopolymer comprising the acrylic compound as a monomer may be 150°C or lower, specifically 110°C or lower, and more specifically 20 to 110°C. The glass transition temperature of the homopolymer comprising the acrylic compound as a monomer must satisfy the above numerical range so that reflow characteristics may be advantageous during low-temperature curing. In addition, the weight-average molecular weight of the homopolymer comprising the acrylic compound as a monomer may be 3,000 to 7,000 g / mol.

[0031] The monomer having a glass transition temperature of 150°C or lower is, for example, methyl methacrylate, glycidyl methacrylate, styrene, ethyl methacrylate, isobornyl acetate, epoxycyclohexyl methyl methacrylate, N-butyl methacrylate, isobutyl methacrylate, vinyl acetate, N-butyl acrylate, 2-ethylhexyl acrylate, acrylic acid, cyclohexyl methacrylate, lauryl acrylate, ethylene glycol dimethyl acrylate, ethylene glycol methyl ether acrylate, phenoxyethyl acrylate, phenoxypolyethylene glucoacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxy-3-phenoxypropylacrylic acid, 2-(acryloyloxy)ethyl hydrogen succinate, neopentyl glycol diacrylate, It may be 3-methyl-1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, etc.

[0032] The initiator according to the present invention may be any one selected from the group consisting of radical photoinitiators, ionic photoinitiators, and combinations thereof.

[0033] The content of the initiator according to the present invention may be 2 to 40 parts by weight based on 100 parts by weight of the alkali-soluble resin, specifically 2 to 20 parts by weight, and more specifically 3 to 10 parts by weight. If the content of the initiator is below the above numerical range, there is a problem that the residual film rate deteriorates due to low sensitivity, and if it exceeds the above numerical range, there may be a problem that the developability decreases and the resolution is reduced.

[0034] The above radical photoinitiator can photocur the vinyl groups of an alkali-soluble resin and a polyfunctional compound.

[0035] The above radical photoinitiator is, for example, an acetophenone-based compound such as 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, diethoxyacetophenone, p-dimethylaninoacetophenone, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexylphenylketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinoyl)phenyl]-1-butanone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, Benzoin compounds such as benzyldimethylketal, benzophenone compounds such as benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4-benzoyl-4'-methyldiphenylsulfide, 3,3',4,4'-tetra(t-butylphooxycarbonyl)benzophenone, thioxantone compounds such as thioxantone, 2-chlorothioxantone, 2-methyldioxantone, isopropylthioxantone, 2,4-diisopropylthioxantone, 2,4-diethylthioxantone, 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, Triazine compounds such as 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-tolyl)-4,6-bis(trichloromethyl)-s-triazine, 2-pifenonyl-4,6-bis(trichloromethyl)-s-triazine, 2,4-bis(trichloromethyl)-6-styryl-s-triazine, 2-(naphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxy-naphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2,4-trichloromethyl-(pifenyl)-6-triazine, and 2,4-trichloromethyl(4'-methoxystyryl)-6-triazine. 2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione, 1-(O-acetyloxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-ethanone, O-ethoxycarbonyl-α-oxyamino-1-phenylpropan-1-one, 1,2-octanedione,2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholine-4-yl-phenyl)-butan-1-one, 1-(4-phenylsulfanylphenyl)-butan-1,2-dione-2-oxime-O-benzoate, 1-(4-phenylsulfanylphenyl)-octane-1,2-dione-2-oxime-O-benzoate, 1-(4-phenylsulfanylphenyl)-octane-1-on-oxime-O-acetate, 1-(4-phenylsulfanylphenyl)-butan-1-on-oxime-O-acetate, 2-(O-benzoyloxime)-1-[4-(phenylthio)p-methylphenyl]-1,2-octanedione, 2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-phenyldione, Oxime ester compounds such as 2-(O-acetyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione, 2-(O-acetyloxime)-1-[4-(phenylthio)phenyl]-1,2-phenyldione, 2-(O-acetyloxime)-1-[4-(phenylthio)phenyl]-1,2-methyldione, O-(acetyl)-N-(1-phenyl-2-oxo-2-(4'-methoxy-naphthyl)ethylidene)hydroxylamine, phosphine compounds such as bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2,2'-bis(o-chlorophenyl)-4,5,4',5'-tetraphenyl-1,2'-biimidazole, It may be imidazole compounds such as 2,2'-bis(o-methoxyphenyl)-4,4',5,5'-tetraphenylbiimidazole and 2,2'-bis(o-methoxyphenyl)-4,4',5,5'-tetra(p-methylphenyl)biimidazole, quinone compounds such as 9,10-phenanthrenquinone, camperquinone, and ethylanthraquinone, borate compounds, carbazole compounds, titanocene compounds, etc.

[0036] The above ionic photoinitiator can photocur the epoxy-based additive described later and can be classified into cationic photoinitiators and anionic photoinitiators.

[0037] The above-mentioned cationic photoinitiators may be, for example, sulfonium salts, iodinium salts, phosphonium salts, diazonium salts, pyridinium salts, benzothiazolium salts, sulfoxonium salts, ferrocene compounds, nitrobenzylsulfonates, alkyl or allyl-N-sulfonyloxyimides, alkyl sulfonic acid esters, oximesulfonates, etc., but are not limited to these. Examples of other aforementioned cationic photoinitiators include tetrabutylammonium tetrafluoroborate, tetrabutylammonium hexafluorophosphate, tetrabutylammonium hydrogen sulfate, tetraethylammonium tetrafluoroborate, tetraethylammonium, p-toluenesulfonate, N,N-dimethyl-N-benzylanilinium antimony hexafluoride, N,N-dimethyl-N-benzylanilinium boron tetrafluoride, N,N-dimethyl-N-benzylpyridinium antimony hexafluoride, N,N-dimethyl-N-benzyltrifluoromethanesulfonic acid, N,N-dimethyl-N-(4-methoxybenzyl)pyridinium antimony hexafluoride, N,N-dimethyl-N-(4-methoxybenzyl)toluidinium antimony hexafluoride, ethyltriphenylphosphonium antimony hexafluoride. Tetrabutylphosphonium antimony hexafluoride, triphenylsulfonium boron tetrafluoride, triphenylsulfonium antimony hexafluoride, triphenylsulfonium arsenic hexafluoride, tri(4-methoxyphenyl)sulfonium arsenic hexafluoride, diphenyl(4-phenylthiophenyl)sulfonium arsenic hexafluoride, diphenyliodonium arsenic hexafluoride, di-4-chlorophenyliodonium arsenic hexafluoride, di-4-bromophenyliodonium arsenic hexafluoride, phenyl(4-methoxyphenyl)iodonium arsenic hexafluoride, diphenyliodonium phosphorus hexafluoride, di-4-chlorophenyliodonium phosphorus hexafluoride, di-4-bromophenyliodonium arsenic hexafluoride, phenyl(4-methoxyphenyl)iodonium arsenic hexafluoride, 4-methylphenyl(4-(2-methylpropylphenyl))iodonium phosphorus hexafluoride, Di-4-tetraphenyliodonium hexafluoride phosphorus, diphenyliodonium hexafluoride phosphorus, di-4-tetraphenyliodonium hexafluoride antimony, diphenyliodonium hexafluoride antimony, 4-methylphenyl(4-(2-methylpropylphenyl))iodonium tetrafluoride arsenic, etc., but are not limited to these.

[0038] Examples of the above anionic photoinitiators include benzoin carbamate, dimethylbenzyloxycarbamoylamine, o-acyloxime, o-nitrobenzoin carbamate, formanilide derivatives, α-ammonium acetophenone, etc.

[0039] According to another embodiment of the present invention, the weight ratio of the radical photoinitiator and the ion photoinitiator (radical photoinitiator: ion photoinitiator) may be 1:0.2 to 1:0.9, specifically 1:0.5 to 1:0.9, and more specifically 1:0.7 to 1:0.9. As the weight ratio of the radical photoinitiator and the ion photoinitiator (radical photoinitiator: ion photoinitiator) satisfies the above numerical range, a cured film having high hardness can be realized and no residue may be generated.

[0040] The photosensitive resin composition according to the present invention may include a polyfunctional compound to control the sensitivity or processability of a cured film made from the photosensitive resin composition.

[0041] The content of the polyfunctional compound according to the present invention may be 2 to 100 parts by weight based on 100 parts by weight of the alkali-soluble resin, specifically 10 to 30 parts by weight, and more specifically 10 to 20 parts by weight. If the content of the polyfunctional compound is below the above numerical range, a problem may arise in which the residual film rate is low due to low sensitivity, and if it exceeds the above numerical range, a problem may arise in which developability is reduced and resolution is lowered.

[0042] The polyfunctional compound according to the present invention may be any one selected from the group consisting of polyfunctional oligomers, polyfunctional monomers, and mixtures thereof.

[0043] The above-mentioned polyfunctional oligomer may be, for example, one or more mixtures selected from the group consisting of aliphatic urethane acrylate oligomers, aromatic urethane acrylate oligomers, epoxy acrylate oligomers, epoxy methacrylate oligomers, polyester acrylate oligomers, silicone acrylate oligomers, melamine acrylate oligomers, and dendritic acrylate oligomers, having 2 to 20 functional groups.

[0044] The above-mentioned polyfunctional monomer may be, for example, one or more mixtures selected from the group consisting of 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, ethylene glycol diacrylate, trimethylolpropane diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, dipentaerythritol hexadiaacrylate, dipentaerythritol tridiaacrylate, dipentaerythritol diacrylate, sorbitol triacrylate, bisphenol A diacrylate derivatives, and dipentaerythritol polyacrylate.

[0045] The photosensitive resin composition according to the present invention includes a plasticizer to form a pattern-forming taper under low-temperature curing conditions.

[0046] The plasticizer according to the present invention may be one or more selected from the group consisting of phthalate-based compounds, adipate-based compounds, phosphate-based compounds and monoisobutyrate-based compounds.

[0047] For example, the above phthalate-based compound may be dioctyl phthalate, diisononyl phthalate, etc., the above adipate-based compound may be dioctyl adipate, the above phosphate-based compound may be tricresyl phosphate, and the above monoisobutyrate-based compound may be 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate.

[0048] The content of the plasticizer according to the present invention may be greater than 1 and less than 30 parts by weight based on 100 parts by weight of the alkali-soluble resin, specifically greater than 1 and less than 11 parts by weight, more specifically 2 to 10 parts by weight, and even more specifically 5 to 10 parts by weight. If the content of the plasticizer is less than the above numerical range, there is a possibility that an under-cut may occur when forming a pattern, and if it exceeds the above numerical range, the hardness of the cured film may become excessively low.

[0049] The photosensitive resin composition according to the present invention includes an epoxy-based additive to compensate for the decrease in hardness of the cured film caused by the addition of the plasticizer.

[0050] The content of the epoxy additive according to the present invention may be greater than 0 and less than 15 parts by weight based on 100 parts by weight of the alkali-soluble resin, specifically greater than 0 and less than 7 parts by weight, more specifically 1 to 6 parts by weight, and even more specifically 3 to 5 parts by weight. If the content of the epoxy additive is less than the above numerical range, the hardness may not be sufficiently high, and if it exceeds the above numerical range, a problem of residue remaining may occur.

[0051] The above epoxy additive may be an aliphatic compound. The above epoxy additive may be an aliphatic compound containing two or more aliphatic ring structures containing epoxy groups. Specifically, the above epoxy additive may include an aliphatic ring structure containing two or more epoxy groups at the chain ends. For example, the above epoxy additive may include an aliphatic ring structure containing one epoxy group at one end; and an aliphatic ring structure containing one epoxy group at the other end.

[0052] According to another embodiment of the present invention, the epoxy additive may further comprise an organic group having 2 to 70 carbon atoms having one or more ester groups as a linker of the aliphatic ring structures. The 'organic group having 2 to 70 carbon atoms having one or more ester groups' may be, for example, a chain or branched alkyl group having 2 to 70 carbon atoms having one or more ester groups. However, the technical concept of the present invention is not limited to alkyl groups, and various organic groups may be applied.

[0053] According to one embodiment of the present invention, the epoxy additive may be a compound represented by the following chemical formula 1 or 2.

[0054] [Chemical Formula 1]

[0055]

[0056] In the above chemical formula 1, n can be an integer from 1 to 10, specifically an integer from 1 to 5, and more specifically an integer from 1 to 2.

[0057] [Chemical Formula 2]

[0058]

[0059] In the above chemical formula 2, n can be an integer from 1 to 10, specifically an integer from 1 to 5, and more specifically an integer from 1 to 2.

[0060] According to another embodiment of the present invention, the weight ratio of the plasticizer to the epoxy additive (plasticizer:epoxy additive) may be 10:1 to 10:25, specifically 10:1 to 10:6, and more specifically 10:5 to 10:6. When the weight ratio of the plasticizer to the epoxy additive is within the above numerical range, pure taper, high hardness, and high flatness characteristics may be realized, and no residue may be generated.

[0061] The photosensitive resin composition according to the present invention may further include a black pigment to impart coloring and light-blocking properties. Specifically, the black pigment may be, for example, a powder or particles of carbon black, alumina, titanium dioxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomite, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, fine silica powder, silicon carbide, silicon nitride, boron carbide, tungsten carbide, titanium carbide, etc. The powder or particles may be dispersed in a dispersion medium as needed. In addition, the content of the black pigment may be appropriately adjusted according to the application.

[0062] The photosensitive resin composition according to the present invention may further include additives as needed. The additive may be, for example, any one selected from the group consisting of crosslinking agents, dispersants, silane coupling agents, and combinations thereof. The content of the additive may be appropriately adjusted to suit each purpose and application.

[0063] The above-mentioned crosslinking agent may be, for example, a melamine-based crosslinking agent, and specifically, the above-mentioned melamine-based crosslinking agent may be methoxymethyl melamine, hexamethoxymethyl melamine, alkoxyalkylmethanol melamine, carboxymethyl melamine, a melamine-based compound having a hydroxymethylamino group, etc.

[0064] The above-mentioned dispersant may be, for example, a surfactant added to improve the applicability or developability of a photosensitive resin composition. The above-mentioned surfactant may be, for example, a silicone-based compound or a fluorine-based compound. The above-mentioned silicone-based compound may be, for example, polydimethylsiloxane, and the above-mentioned fluorine-based compound may be, for example, BM-1000, BM-1100 (BM Chemie), Prolide FC-135 / FC-170C / FC-430 (Sumitomo 3M), SH-28PA / -190 / SZ-6032 (Tore Silicon Co., Ltd.), etc.

[0065] The above silane coupling agent may be necessary, for example, to improve the adhesion between the photosensitive resin composition and the underlying substrate. The above silane coupling agent is, for example, (3-glycidoxypropyl)trimethoxysilane, (3-glycidoxypropyl)triethoxysilane, (3-glycidoxypropyl)methyldimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane, (3-glycidoxypropyl)dimethylethoxysilane, 3,4-epoxybutyltrimethoxysilane, 3,4-epoxybutyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, 3-triethoxysili-N-(1,3-dimethyl-butylidene)propylamine, N-2(aminoethyl)3-aminopropyltrimethoxysilane, It may be one or more mixtures selected from the group consisting of N-2(aminoethyl)3-aminopropyltriethoxysilane, N-2(aminoethyl)3-aminopropylmethyldimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane and (3-isocyanatepropyl)triethoxysilane.

[0066] The photosensitive resin composition according to the present invention may further include a solvent to minimize residual solvent and ensure chemical resistance during a low-temperature curing process. Specifically, the boiling point of the solvent may be less than 150°C, and more specifically, less than 60 to 150°C.

[0067] The above solvent may be, for example, any one selected from the group consisting of ester-based solvents, ether-based solvents, alcohol-based solvents, and mixtures thereof.

[0068] The above ester-based solvent may be, for example, one or more mixtures selected from the group consisting of methyl-2-hydroxyisobutyrate, ethylene glycol monomethyl ether acetate, 2-methoxy-1-methylethyl ester, propylene acetate, ethyl propionate, and ethyl pyruvate.

[0069] The above ether-based solvent may be, for example, one or more mixtures selected from the group consisting of 1-methoxy-2-propanol, dibutyl ether, ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, propylene glycol dimethyl ether, and tetrahydrofuran.

[0070] The above alcohol solvent may be, for example, one or more mixtures selected from the group consisting of methanol, ethanol, and isopropyl alcohol.

[0071] The solvent according to the present invention may be added so that the total solid content of the photosensitive resin composition is 10 to 50 weight percent. The content of the solvent must satisfy the above numerical range so that a thin film can be effectively formed with the photosensitive resin composition.

[0072] 2. Display device

[0073] Another embodiment of the present invention provides a display device comprising a cured film prepared from the photosensitive resin composition. By using the photosensitive resin composition, curing is possible at a low temperature of 150°C or lower, and a black matrix pattern with a net taper can be formed. That is, the cured film may be a black matrix with a net taper shape containing a black pigment.

[0074] A display device according to one embodiment of the present invention may be a device in which a pattern is formed using the photosensitive resin composition, and specifically, may be a flexible display device having flexibility.

[0075] A display device according to another embodiment of the present invention may include a cured film made of the photosensitive resin composition patterned on a substrate. The substrate may be, for example, a substrate commonly used in flexible display devices, a glass substrate, or a substrate made of plastic material.

[0076] 3. Pattern formation method

[0077] Another embodiment of the present invention provides a pattern forming method comprising the steps of: (S1) applying the photosensitive resin composition on a substrate to form a coating film; (S2) positionally exposing the coating film and then removing the unexposed coating film with a developer; and (S3) curing the exposed coating film.

[0078] The above step (S3) may be a step performed at 80 to 150°C, and specifically a step performed at 80 to 100°C.

[0079] Generally, it is known that a photosensitive resin composition must undergo a post-curing process at 150 to 300°C to obtain a stable cured film. However, there was a problem in applying a curing step of 150°C or higher to a device based on a flexible material having low heat resistance performance of around 100 to 130°C. According to one embodiment of the present invention, by using the photosensitive resin composition, a patterning method can be implemented that forms a net taper when forming a pattern even at low temperatures and has high hardness, excellent adhesion to a substrate, and high flatness characteristics.

[0080] Hereinafter, embodiments of the present invention are described in detail so that those skilled in the art can easily implement the present invention; however, this is merely an example, and the scope of the present invention is not limited by the following.

[0081] [Synthesization Example 1: Synthesis of Alkali-Soluble Resin]

[0082] A mixed solution was prepared by adding 400 parts by weight of propylene glycol methyl ether acetate, 70 parts by weight of methacrylic acid (glass transition temperature of the homopolymer 228°C), 10 parts by weight of styrene, 10 parts by weight of N-phenyl maleimide, and 10 parts by weight of benzyl methacrylate to a flask equipped with a cooler and a stirrer. After thoroughly stirring the mixture in the flask at 90 rpm with the stirrer, 15 parts by weight of 2,2'-azobis(2,4-dimethylvaleronitrile) were added as a polymerization initiator to prepare a polymerization mixed solution. The polymerization mixed solution was slowly heated to 60°C and maintained at 60°C for 16 hours. Afterwards, the maintained polymerization mixture solution was cooled to room temperature, and 0.05 parts by weight of hydrobenzophenone, a polymerization inhibitor, was added to obtain a polymer solution having a solid content of 30% by weight based on the total weight of the polymer solution.

[0083] As a result of measuring by Gel Permeation Chromatography (GPC), the weight-average molecular weight of the obtained alkali-soluble resin, equivalent to standard polystyrene, is 10,000 g / mol.

[0084] [Synthesization Example 2: Synthesis of Alkali-Soluble Resin]

[0085] An alkali-soluble resin was synthesized in the same manner as in Synthesis Example 1, but instead of the mixed solution according to Synthesis Example 1, a mixed solution comprising 400 parts by weight of propylene glycol methyl ether acetate, 70 parts by weight of acrylic acid, 4 parts by weight of styrene, 4 parts by weight of N-phenyl maleimide, and 22 parts by weight of benzyl methacrylate was used.

[0087] <Preparation Example: Preparation of a Photosensitive Resin Composition>

[0088] Photosensitive resin compositions were prepared according to the following examples and comparative examples, and their formulation ratios are summarized in Tables 1 and 2 below. The content of each component was set based on 100 parts by weight of alkali-soluble resin.

[0089] <Example 1>

[0090] 100 parts by weight of the alkali-soluble resin synthesized in Synthesis Example 2 above, 10 parts by weight of a radical photoinitiator (2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione), 5 parts by weight of an ionic photoinitiator (di-4-bromophenyliodonium hexafluoride), 10 parts by weight of a polyurethane acrylate oligomer containing 10 functional groups, 20 parts by weight of a polyfunctional monomer (dipentaerythritol hexaacrylate), 5 parts by weight of a silane coupling agent ((3-glycidoxypropyl)methyldiethoxysilane), 80 parts by weight of a black pigment (carbon black), 10 parts by weight of a plasticizer (monoisobutyrate; KYOWANOL M of KH Neochem Co., Ltd.), and an epoxy additive (3,4-epoxycyclohexylmethyl 5 parts by weight of 3,4-epoxycyclohexane-carboxylate) were mixed. A solvent (propylene glycol methyl ether acetate) was dissolved in the mixture so that the concentration of solids was 20% by weight based on the total weight of the photosensitive resin composition, and the resulting product was filtered through a 0.2 μm millipore filter to finally prepare a photosensitive resin composition.

[0092] <Example 2: Use of alkali-soluble resin according to Synthesis Example 1, unlike Example 1>

[0093] A photosensitive resin composition was prepared in the same manner as in Example 1, but instead of the alkali-soluble resin according to Synthesis Example 2, the alkali-soluble resin according to Synthesis Example 1 was used.

[0095] <Examples 3 to 5: Cases where only the content of the ionic photoinitiator was varied>

[0096] A photosensitive resin composition was prepared in the same manner as in Example 1, but the content of the ionic photoinitiator (di-4-bromophenyliodonium hexafluoride) was changed from 5 parts by weight to 7 parts by weight (Example 3), 9 parts by weight (Example 4), and 2 parts by weight (Example 5), respectively.

[0098] <Examples 6 to 8: Cases where only the plasticizer content is varied>

[0099] A photosensitive resin composition was prepared in the same manner as in Example 1, but the content of the plasticizer (monoisobutyrate) was changed from 10 parts by weight to 2 parts by weight (Example 6), 5 parts by weight (Example 7), and 10 parts by weight (Example 8), respectively.

[0101] <Examples 9 to 11: Cases where the content of epoxy-based additives was varied>

[0102] A photosensitive resin composition was prepared in the same manner as in Example 1, but the content of the epoxy-based additive (3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane-carboxylate) was changed from 5 parts by weight to 1 part by weight (Example 9), 2 parts by weight (Example 10), and 6 parts by weight (Example 11), respectively.

[0104] <Example 12: When the weight ratio of plasticizer to epoxy additive is 10:5>

[0105] A photosensitive resin composition was prepared in the same manner as in Example 1, but the content of the plasticizer (monoisobutyrate) was changed from 10 parts by weight to 30 parts by weight, and the content of the epoxy additive (3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane-carboxylate) was changed from 5 parts by weight to 15 parts by weight.

[0107] <Example 13: When the weight ratio of plasticizer to epoxy additive is 10:14>

[0108] A photosensitive resin composition was prepared in the same manner as in Example 1, but the content of the plasticizer (monoisobutyrate) was changed from 10 parts by weight to 8.4 parts by weight, and the content of the epoxy additive (3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane-carboxylate) was changed from 5 parts by weight to 12 parts by weight.

[0110] <Example 14: When the weight ratio of plasticizer to epoxy additive is 10:5.7> >

[0111] A photosensitive resin composition was prepared in the same manner as in Example 1, but the content of the plasticizer (monoisobutyrate) was changed from 10 parts by weight to 21 parts by weight, and the content of the epoxy additive (3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane-carboxylate) was changed from 5 parts by weight to 12 parts by weight.

[0113] <Examples 15 to 17: Cases where the content of the epoxy-based additive was varied, unlike Example 12>

[0114] A photosensitive resin composition was prepared in the same manner as in Example 12, but the content of the epoxy additive (3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane-carboxylate) was changed from 15 parts by weight to 3 parts by weight (Example 15), 6 parts by weight (Example 16), and 12 parts by weight (Example 17), respectively.

[0116] <Examples 18 to 20: Cases where the content of the ionic photoinitiator is different from Example 1>

[0117] A photosensitive resin composition was prepared in the same manner as in Example 1, but the content of the ionic photoinitiator (di-4-bromophenyliodonium hexafluoride) was changed from 5 parts by weight to 0 parts by weight (Example 18), 1 part by weight (Example 19), and 10 parts by weight (Example 20), respectively.

[0119] <Examples 21 and 22: Cases where the content of the epoxy additive was different from Example 1>

[0120] A photosensitive resin composition was prepared in the same manner as in Example 1, but the content of the epoxy additive was changed from 5 parts by weight to 0.9 parts by weight (Example 21) and 7 parts by weight (Example 22), respectively.

[0122] <Comparative Example 1: Case where neither epoxy additives nor plasticizers are used>

[0123] A photosensitive resin composition was prepared in the same manner as in Example 1, but with all epoxy additives and plasticizers removed.

[0125] <Comparative Example 2: Unlike Comparative Example 1, when an epoxy-based additive is added>

[0126] A photosensitive resin composition was prepared in the same manner as in Comparative Example 1, but 5 parts by weight of an epoxy-based additive (3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane-carboxylate) were additionally added.

[0128] <Comparative Example 3: Case where a plasticizer was added, unlike Comparative Example 2>

[0129] A photosensitive resin composition was prepared in the same manner as Comparative Example 2, but with an additional addition of 1 part by weight of a plasticizer (monoisobutyrate).

[0131] <Comparative Example 4: Unlike Comparative Example 1, the ionic photoinitiator is removed>

[0132] A photosensitive resin composition was prepared in the same manner as Comparative Example 1, but without using an ionic photoinitiator.

[0134] <Comparative Example 5: Case where an excess amount of epoxy-based additive is added, unlike Example 1>

[0135] A photosensitive resin composition was prepared in the same manner as in Example 1, but the content of the epoxy additive was changed from 5 parts by weight to 26 parts by weight.

[0137] <Comparative Example 6: Case where the plasticizer content is different from Example 1>

[0138] A photosensitive resin composition was prepared in the same manner as in Example 1, but the content of the plasticizer (monoisobutyrate) was changed from 10 parts by weight to 31 parts by weight.

[0140] <Comparative Example 7: Case where the content of plasticizer and epoxy-based additive is different from Example 1>

[0141] A photosensitive resin composition was prepared in the same manner as in Example 1, but the content of the plasticizer (monoisobutyrate) was changed from 10 parts by weight to 13.2 parts by weight, and the content of the epoxy additive was changed from 5 parts by weight to 16 parts by weight.

[0143] <Comparative Example 8: Case where epoxy-based additives are not used, unlike Example 1>

[0144] A photosensitive resin composition was prepared in the same manner as in Example 1, but the epoxy additive was removed.

[0145] Unit: parts by weight bookbinder 1) (Synthetic Example) RI 2) II 3) 10MM 4) MM 5) pigment 6) coupling agent 7) Plasticizer (P) 8) Epoxy additive (E) 9) P:E(w / w) Example 1 100(2) 10 5 10 20 80 5 10 5 10:5 Example 2 100(1) 10 5 10 20 80 5 10 5 10:5 Example 3 100(2) 10 7 10 20 80 5 10 5 10:5 Example 4 100(2) 10 9 10 20 80 5 10 5 10:5 Example 5 100(2) 10 2 10 20 80 5 10 5 10:5 Example 6 100(2) 10 5 10 20 80 5 2 5 10:25 Example 7 100(2) 10 5 10 20 80 5 5 5 10:10 Example 8 100(2) 10 5 10 20 80 5 10 5 10:5 Example 9 100(2) 10 5 10 20 80 5 10 1 10:1 Example 10 100(2) 10 5 10 20 80 5 10 2 10:2 Example 11 100(2) 10 5 10 20 80 5 10 6 10:6 Example 12 100(2) 10 5 10 20 80 5 30 15 10:5 Example 13 100(2) 10 5 10 20 80 5 8.4 12 10:14 Example 14 100(2) 10 5 10 20 80 5 21 12 10:5.7 Example 15 100(2) 10 5 10 20 80 5 30 3 10:1 Example 16 100(2) 10 5 10 20 80 5 30 6 10:2 Example 17 100(2) 10 5 10 20 80 5 30 12 10:4 1) Binder: Alkali-soluble resin (Synthetic Example 1 or 2) 2) RI: Radical photoinitiator (2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione) 3) II: Ionic photoinitiator (di-4-bromophenyliodonium hexafluoride) 4) 10MM: Polyurethane acrylate oligomer containing 10 functional groups 5) MM: Polyfunctional monomer (dipentaerythritol hexaacrylate) 6) Pigment: Carbon black 7) Coupling agent: (3-glycidoxypropyl)methyldiethoxysilane 8) Plasticizer: Monoisobutyrate 9) Epoxy additive: 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane-carboxylate The above 1) to 9) are identical in Table 2 below.

[0146] Unit: parts by weight Binder (Synthetic Example) RI II 10mm MM pigment coupling agent Plasticizer (P) Epoxy additive (E) P:E(w / w) Example 18 100(2) 10 0 10 20 80 5 10 5 10:5 Example 19 100(2) 10 1 10 20 80 5 10 5 10:5 Example 20 100(2) 10 10 10 20 80 5 10 5 10:5 Example 21 100(2) 10 5 10 20 80 5 10 0.9 10:0.9 Example 22 100(2) 10 5 10 20 80 5 10 7 10:7

[0147] Unit: parts by weight Binder (Synthetic Example) RI II 10mm MM pigment coupling agent Plasticizer (P) Epoxy additive (E) P:E(w / w) Comparative Example 1 100(2) 10 5 10 20 80 5 0 0 0:0 Comparative Example 2 100(2) 10 5 10 20 80 5 0 5 0:1 Comparative Example 3 100(2) 10 5 10 20 80 5 1 5 10:50 Comparative Example 4 100(2) 10 0 10 20 80 5 0 0 0:0 Comparative Example 5 100(2) 10 5 10 20 80 5 10 26 10:26 Comparative Example 6 100(2) 10 5 10 20 80 5 31 5 1:0.1 Comparative Example 7 100(2) 10 5 10 20 80 5 13.2 16 10:12 Comparative Example 8 100(2) 10 5 10 20 80 5 10 0 1:0

[0149] [Experimental Example: Evaluation of a Cured Film Prepared with a Photosensitive Resin Composition]

[0150] A photosensitive resin composition according to the above preparation example was applied to a bare glass substrate using a slit coater, and then pre-baked on a hot plate at 85°C for 2 minutes to form a film with a thickness of 2.0 μm. A predetermined pattern mask was applied to the obtained film to obtain an intensity of 100 mW / cm² at 365 nm. 2 100 mJ of UV light was irradiated using a broadband exposure unit. Subsequently, the material was developed with an aqueous tetramethylammonium hydroxide solution (2.38 wt%) at 23°C for 60 seconds, followed by rinsing with ultrapure water for 60 seconds. For final curing, the patterned film was heated in an oven at 85°C for 60 minutes. 10 µm lines and spaces were analyzed using a Scanning Electron Microscope (SEM).

[0151] 1) Pure Taper

[0152] O was indicated if there was no undercut of the lower critical dimension (CD) size, △ was indicated if the combined length of the undercut on both sides was 0.1 to 0.9 μm, and X was indicated if it was 1.0 μm or more. When the undercut was 0, 'O' was indicated if the taper angle was greater than 80° and less than or equal to 90°; '◎' was indicated if it was 80° or less.

[0153] 2) Hardness

[0154] The above line was measured using a Nano Indenter (HM200) under measurement conditions (F=200 uN, loading / unloading time=5 sec, creep time=2 sec, 3 times). The plastic hardness was 350 N / mm. 2If it is above that, O, especially 370 N / mm 2 ◎ if greater than or equal to, 320 to less than 350 N / mm 2 On the reverse side △, 319 N / mm 2 If less than or equal to, it was marked as X.

[0155] 3) Leveling

[0156] A photosensitive resin composition according to the above manufacturing example was spin-coated onto a substrate (glass) on which a lower pattern film was formed with a line and space of 20㎛ and a 1:1 ratio, respectively, and a flat portion was manufactured under the above curing conditions. Subsequently, the degree of planarization (DOP) was calculated according to the following Equation 1. If the calculated value was 85% or higher, it was indicated as O; specifically, if it was 88% or higher, it was indicated as ◎; if it was 76% to 84%, it was indicated as △; and if it was 75% or lower, it was indicated as X.

[0157] [Equation 1]

[0158] DOP(%)={①-(②-③)} / ①

[0159] (In Equation 1 above, ① = thickness of the lower pattern film, ② = maximum thickness of the flat portion with the lower pattern film, and ③ = maximum thickness of the flat portion without the lower pattern film.)

[0160] 4) Residue

[0161] In the above Line & Space, if the residue in the space between the lines is 0.4㎛ (5% of the area) or less, it is marked as 'O', if it is 0, it is marked as '◎', if the residue is less than 0.5 to 1㎛, it is marked as '△', and if the residue is 1㎛ or more, it is marked as 'X'.

[0162] Pure taper hardness flattening Residue Example 1 ◎ ◎ ◎ O Example 2 O ◎ O O Example 3 ◎ ◎ ◎ O Example 4 ◎ ◎ ◎ O Example 5 ◎ O ◎ O Example 6 O ◎ O O Example 7 O ◎ O O Example 8 ◎ ◎ ◎ O Example 9 ◎ O ◎ O Example 10 ◎ O ◎ O Example 11 ◎ ◎ ◎ O Example 12 O O O O Example 13 O O O O Example 14 O O O O Example 15 O O O O Example 16 O O O O Example 17 O O O O

[0163] Pure taper hardness flattening Residue Example 18 O △ O O Example 19 O △ O O Example 20 O O O △ Example 21 O △ O O Example 22 △ O △ △

[0164] Pure taper hardness flattening Residue Comparative Example 1 X X X O Comparative Example 2 X O X O Comparative Example 3 △ O △ O Comparative Example 4 X X X O Comparative Example 5 X X X O Comparative Example 6 O X O O Comparative Example 7 X O X X Comparative Example 8 △ X △ O

[0165] Referring to Examples 1 and 2 in Table 4 above, it can be seen that the net taper and flattening performance are further improved by using acrylic acid instead of methacrylic acid as a monomer for synthesizing alkali-soluble resins.

[0166] Referring to Examples 1 and 3 to 5 in Table 4 above, it can be confirmed that when the weight ratio of the radical photoinitiator to the ion photoinitiator (radical photoinitiator: ion photoinitiator) is 1:0.7 to 1:0.9, an optimal cured film having high hardness can be realized and no residue is generated.

[0167] Referring to Examples 6 to 11 in Table 4 above, when the weight ratio of the plasticizer to the epoxy additive (plasticizer:epoxy additive) is 10:1 to 10:6, the net taper and flattening performance can be simultaneously improved, and a cured film having high hardness can be realized.

[0168] Referring to Tables 4 and 6 above, Comparative Examples 1 and 4, which do not use either a plasticizer or an epoxy-based additive, had problems such as low hardness of the cured film, as well as poor net taper and planarization performance. In addition, Comparative Example 2, which uses only the epoxy-based additive among the plasticizer and the epoxy-based additive, can achieve a cured film with low hardness but has the problem of not improving net taper and planarization performance, and Comparative Example 8, which uses only the plasticizer, has the problem of very low hardness of the cured film due to the non-use of the epoxy-based additive. On the other hand, according to Examples 1 to 22, which use both the epoxy-based additive and the plasticizer, by using appropriate amounts of the plasticizer and the epoxy-based additive, it is possible to achieve both a cured film with high hardness and high net taper and planarization performance.

[0169] Comparing Comparative Examples 3, 5, and 6 with the Examples, it was confirmed that the net taper and flattening performance were improved when the content of the plasticizer was greater than 1 and less than 30 parts by weight based on 100 parts by weight of the alkali-soluble resin, and specifically, further improved when it was greater than 1 and less than 11 parts by weight. In addition, comparing Comparative Examples 7 and 8 with the Examples, it was confirmed that the high hardness cured film and net taper and flattening performance were improved when the content of the epoxy additive was greater than 0 and less than 15 parts by weight based on 100 parts by weight of the alkali-soluble resin, and specifically, further improved when it was greater than 0 and less than 7 parts by weight.

[0170] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims are also included within the scope of the present invention.

Claims

Claim 1 A photosensitive resin composition comprising: 100 parts by weight of an alkali-soluble resin; 2 to 40 parts by weight of an initiator; 2 to 100 parts by weight of a polyfunctional compound; more than 1 and less than or equal to 30 parts by weight of a plasticizer; and more than 0 and less than or equal to 15 parts by weight of an epoxy additive; wherein the initiator is any one selected from the group consisting of radical photoinitiators, ionic photoinitiators, and combinations thereof, and the weight ratio of the radical photoinitiator to the ionic photoinitiator (radical photoinitiator: ionic photoinitiator) is 1:0.2 to 1:0.

9. Claim 2 A photosensitive resin composition according to claim 1, wherein, based on 100 parts by weight of the alkali-soluble resin, the content of the plasticizer is greater than 1 and less than 11 parts by weight, and the content of the epoxy-based additive is greater than 0 and less than 7 parts by weight. Claim 3 A photosensitive resin composition according to claim 1, wherein the weight-average molecular weight of the alkali-soluble resin is 2,000 to 20,000 g / mol. Claim 4 In claim 1, the alkali-soluble resin is a photosensitive resin composition in which the alkali-soluble resin is a copolymer comprising an acrylic compound as a monomer. Claim 5 A photosensitive resin composition according to claim 4, wherein the glass transition temperature of the homopolymer containing the acrylic compound as a monomer is 150°C or lower. Claim 6 A photosensitive resin composition according to claim 1, wherein the weight ratio of the radical photoinitiator to the ion photoinitiator (radical photoinitiator: ion photoinitiator) is 1:0.5 to 1:0.

9. Claim 7 A photosensitive resin composition according to claim 6, wherein the weight ratio of the radical photoinitiator to the ion photoinitiator (radical photoinitiator: ion photoinitiator) is 1:0.7 to 1:0.

9. Claim 8 A photosensitive resin composition according to claim 1, wherein the polyfunctional compound is any one selected from the group consisting of polyfunctional oligomers, polyfunctional monomers, and mixtures thereof. Claim 9 A photosensitive resin composition according to claim 1, wherein the plasticizer is one or more selected from the group consisting of phthalate-based compounds, adipate-based compounds, phosphate-based compounds and monoisobutyrate-based compounds. Claim 10 A photosensitive resin composition according to claim 1, wherein the weight ratio of the plasticizer to the epoxy-based additive (plasticizer:epoxy-based additive) is 10:1 to 10:

25. Claim 11 In claim 1, the epoxy-based additive is a photosensitive resin composition that is an aliphatic cyclic compound. Claim 12 In claim 11, the above-mentioned epoxy additive is a photosensitive resin composition comprising an aliphatic ring compound having two or more aliphatic ring structures containing epoxy groups. Claim 13 A photosensitive resin composition according to claim 12, wherein the epoxy additive further comprises an organic group having 2 to 70 carbon atoms having one or more ester groups as a linker of the aliphatic ring structures. Claim 14 In claim 11, the photosensitive resin composition wherein the epoxy-based additive is a compound represented by the following chemical formula 1 or 2. [Chemical Formula 1] (In the above Chemical Formula 1, n is an integer from 1 to 10.)[Chemical Formula 2] (In the above Chemical Formula 2, n is an integer from 1 to 10.) Claim 15 A photosensitive resin composition comprising, in addition to, a black pigment in claim 1. Claim 16 A photosensitive resin composition according to claim 1, further comprising an additive; wherein the additive is any one selected from the group consisting of crosslinking agents, dispersing agents, silane coupling agents, and combinations thereof. Claim 17 A display device comprising a cured film made of a photosensitive resin composition according to any one of claims 1 to 16. Claim 18 In claim 17, the above-mentioned cured film is a display device that is a black matrix of a purely tapered shape containing a black pigment. Claim 19 (S1) a step of forming a coating film by applying a photosensitive resin composition according to claim 1 onto a substrate; (S2) a step of selectively exposing the coating film and then removing the unexposed coating film with a developer; and (S3) a step of curing the exposed coating film; wherein the step (S3) is performed at 80 to 150°C.

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