Photosensitive resin composition and insulating film prepared therefrom

Abstract

To provide a photosensitive resin composition which is cured at low temperature and can prepare a colored insulating film containing no dye.SOLUTION: A photosensitive resin composition contains (A) a copolymer, (B) a photopolymerizable compound, (C) a photopolymerization initiator, (D) an isocyanate-based compound, and (E) a cyclic ketone-based compound.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a photosensitive resin composition capable of forming a colored insulating film having excellent film retention, hardness, and resolution, and to an insulating film prepared therefrom. [Background technology]

[0002] An LCD is a display device that displays information on a screen using the anisotropy of the refractive index of liquid crystals. It is composed of an upper substrate, a lower substrate, and liquid crystal inserted between the substrates. In general, the lower substrate includes an array of driving elements, and the upper substrate includes a color filter, and a spacer having a predetermined thickness is disposed to maintain a gap between the substrates. If necessary, a touch screen panel (TSP) or the like can be connected to the upper substrate.

[0003] The spacing and thickness of the spacers need to be precisely adjusted and uniformly formed to reduce deformation caused by external pressure. It is more convenient to use colored column spacers than transparent spacers for this test.

[0004] In addition, when manufacturing an LCD, an insulating film can be employed for the purpose of an alignment key to form a more accurate pattern. Generally, the TSP is manufactured after the assembly process of the LCD in which the color filter and the thin film transistor (TFT) are combined. In order to minimize the influence on the already manufactured color filter, the insulating film of the TSP needs to be cured at a low temperature. However, when cured at a low temperature, there is a problem that the strength of the insulating film is insufficient, so the TSP is manufactured first, and then the color filter is manufactured. In such a case, it is advantageous for the insulating film of the TSP to have a color in order to place the color filter in the correct position.

[0005] Compositions containing dyes (or pigments) are known as a conventional technique for preparing such insulating films having color (see Patent Document 1). However, most of the techniques using dye-containing compositions have poor dispersibility of the dye itself and poor stability in the composition, and are unable to fully satisfy the requirements for developability and resolution. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Korean Patent Application Publication No. 2015-0008759 [Patent Document 2] Korean Patent Application Publication No. 2004-0007700 [Patent Document 3] Korean Patent Application Publication No. 2005-0084149 [Patent Document 4] Korean Patent Application Publication No. 2008-0083650 [Patent Document 5] Korean Patent Application Publication No. 2008-0080208 [Patent Document 6] Korean Patent Application Publication No. 2007-0044062 [Patent Document 7] Korean Patent Application Publication No. 2007-0091110 [Patent Document 8] Korean Patent Application Publication No. 2007-0044753 [Patent Document 9] Korean Patent Application Publication No. 2009-0009991 [Patent Document 10] Korean Patent Application Publication No. 2009-0093933 [Patent Document 11] Korean Patent Application Publication No. 2010-0097658 [Patent Document 12] Korean Patent Application Publication No. 2011-0059525 [Patent Document 13] International Publication No. 10102502 Brochure [Patent Document 14] International Publication No. 10133077 Brochure Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, an object of the present invention is to provide a photosensitive resin composition which can be cured at a low temperature and which can prepare a dye-free colored insulating film. [Means for solving the problem]

[0008] In order to achieve the above object, the present invention provides a photosensitive resin composition comprising (A) a copolymer, (B) a photopolymerizable compound, (C) a photopolymerization initiator, (D) an isocyanate-based compound, and (E) a solvent containing a cyclic ketone-based compound.

[0009] In order to achieve another object, the present invention provides an insulating film prepared from a photosensitive resin composition.

[0010] Advantageous Effects of the Invention The photosensitive resin composition of the present invention can prepare a colored insulating film without using a dye. In addition, the photosensitive resin composition of the present invention can be cured at a low temperature, and can prepare an insulating film excellent in all properties such as film strength, hardness, and resolution. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The present invention is not limited to the following description, but can be modified in various forms without departing from the spirit of the present invention.

[0012] Throughout this specification, when a portion is said to "comprise" certain elements, it is understood that other elements may be included, rather than excluding other elements, unless otherwise specified. Additionally, all numbers and expressions relating to quantities of ingredients, reaction conditions, and the like used in this specification should be understood to be modified by the term "about," unless otherwise specified.

[0013] The present invention provides a photosensitive resin composition comprising (A) a copolymer, (B) a photopolymerizable compound, (C) a photopolymerization initiator, (D) an isocyanate-based compound, and (E) a solvent containing a cyclic ketone-based compound.

[0014] The composition may optionally further comprise (F) a surfactant, and / or (G) a silane coupling agent.

[0015] As used herein, the term "(meth)acrylic" means "acrylic" and / or "methacrylic", and the term "(meth)acrylate" means "acrylate" and / or "methacrylate".

[0016] The weight average molecular weight (g / mole or Da) of each component listed below is determined by gel permeation chromatography (GPC, eluent: tetrahydrofuran) relative to polystyrene standards.

[0017] (A) Copolymer The photosensitive resin composition according to the present invention may contain a copolymer (A) as a binder, as described below.

[0018] The copolymer may contain (a1) structural units derived from an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride, or a combination thereof, (a2) structural units derived from an ethylenically unsaturated compound containing an epoxy group, and (a3) ​​structural units derived from an ethylenically unsaturated compound different from (a1) and (a2).

[0019] (a1) a structural unit derived from an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride, or a combination thereof The structural unit (a1) in the present invention can be derived from an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride, or a combination thereof.

[0020] Ethylenically unsaturated carboxylic acid, ethylenically unsaturated carboxylic acid anhydride, or combinations thereof, are polymerizable unsaturated compounds containing at least one carboxyl group in the molecule. It can be at least one selected from unsaturated monocarboxylic acids, such as (meth)acrylic acid, crotonic acid, α-chloroacrylic acid and cinnamic acid, unsaturated dicarboxylic acids and their anhydrides, such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride and mesaconic acid, unsaturated polycarboxylic acids and their anhydrides having valences of 3 or more, and mono[(meth)acryloyloxyalkyl]esters of polycarboxylic acids having valences of 2 or more, such as mono[2-(meth)acryloyloxyethyl]succinate, mono[2-(meth)acryloyloxyethyl]phthalate, etc. However, it is not limited thereto. Particularly from the viewpoint of developability, (meth)acrylic acid can be preferred among them.

[0021] The content of the structural unit (a1) derived from an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic anhydride, or a combination thereof may be in the range of 5% by weight to 50% by weight, 10% by weight to 40% by weight, or 15% by weight to 35% by weight based on the total molar number of the structural units constituting the copolymer (A). Within the above range, it is possible to achieve pattern formation of the film while maintaining favorable developability.

[0022] (a2) A structural unit derived from an ethylenically unsaturated compound containing an epoxy group The structural unit (a2) of the present invention can be derived from an ethylenically unsaturated compound containing an epoxy group.

[0023] Specifically, the structural unit (a2) may include (a2-1) a structural unit derived from an unsaturated monomer containing an alicyclic epoxy group represented by the following formula 1, and (a2-2) a structural unit derived from an unsaturated monomer containing an acyclic epoxy group represented by the following formula 2. [ka]

[0024] In the above formula, R 2 and R 4 are each independently hydrogen or C 1~4 is alkyl, R 1 and R 3 are each independently 1~4 More specifically, R 2 and R 4 may each independently be hydrogen or methyl; R 1 and R 3 is C 1-4 It may be an alkylene.

[0025] The unsaturated monomer containing an alicyclic epoxy group (a2-1) may be 3,4-epoxycyclohexylmethyl acrylate or 3,4-epoxycyclohexylmethyl methacrylate. The unsaturated monomer containing an acyclic epoxy group (a2-2) may be glycidyl acrylate or glycidyl methacrylate.

[0026] The total content of the structural units (a2-1) and (a2-2) may be in the range of 10 mol% to 50 mol%, 10 mol% to 45 mol%, 10 mol% to 40 mol%, 10 mol% to 30 mol%, 10 mol% to 20 mol%, 15 mol% to 50 mol%, 15 mol% to 45 mol%, 15 mol% to 40 mol%, 15 mol% to 30 mol%, or 15 mol% to 20 mol%, based on the total number of moles of the structural units of the copolymer (A). Within the above range, the storage stability of the composition is maintained and the film retention rate is improved.

[0027] In addition, the molar ratio of the structural units (a2-1) and (a2-2) is 50-99:50-1, 50-90:50-10, 50-85:50-15, 50-80:50-20, or 50-75:50-25. Within the above ranges, it is possible to achieve excellent stability over time at room temperature, heat resistance, and chemical resistance, and pattern formation is promoted.

[0028] (a3) a structural unit derived from an ethylenically unsaturated compound different from (a1) and (a2) The structural unit (a3) ​​of the present invention can be derived from an ethylenically unsaturated compound different from the structural units (a1) and (a2).

[0029] Specifically, the structural unit (a3) ​​may be an ethylenically unsaturated compound having an aromatic ring, such as phenyl(meth)acrylate, benzyl(meth)acrylate, 2-phenoxyethyl(meth)acrylate, phenoxydiethylene glycol(meth)acrylate, p-nonylphenoxypolyethylene glycol(meth)acrylate, p-nonylphenoxypolypropylene glycol(meth)acrylate, tribromophenyl(meth)acrylate, styrene, methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, diethylstyrene, triethylstyrene, propylstyrene, butylstyrene, hexylstyrene, heptylstyrene, octylstyrene, fluorostyrene, chlorostyrene, bromostyrene, iodostyrene, methoxystyrene, ethoxystyrene, propoxystyrene, p-hydroxy-α-methylstyrene, acetylstyrene, vinyltoluene, divinylbenzene, vinylphenol, o-vinylbenzyl methyl ether, m-vinylbenzyl methyl ether, and p-vinylbenzyl methyl ether; an unsaturated carboxylic acid ester, such as methyl(meth)acrylate, acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, cyclohexyl (meth)acrylate, ethylhexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxy-3-chloropropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, glycerol (meth)acrylate, methyl ethyl α-hydroxymethyl acrylate, ethyl α-hydroxymethyl acrylate, propyl α-hydroxymethyl acrylate, butyl α-hydroxymethyl acrylate, 2-methoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, methoxytriethylene glycol (meth)acrylate, methoxytripropylene glycol (meth)acrylate, poly(ethylene glycol) methyl ether (meth)acrylate, tetrafluoropropyl (meth)acrylate,It may be at least one selected from the group consisting of 1,1,1,3,3,3-hexafluoroisopropyl (meth)acrylate, octafluoropentyl (meth)acrylate, heptadecafluorodecyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentanyloxyethyl (meth)acrylate, and dicyclopentenyloxyethyl (meth)acrylate, N-vinyl tertiary amines containing N-vinyl groups, such as N-vinylpyrrolidone, N-vinylcarbazole, and N-vinylmorpholine, unsaturated ethers, such as vinyl methyl ether and vinyl ethyl ether, and unsaturated imides, such as N-phenylmaleimide, N-(4-chlorophenyl)maleimide, N-(4-hydroxyphenyl)maleimide, and N-cyclohexylmaleimide.

[0030] The total content of the structural unit (a3) ​​may be in the range of 5 mol% to 70 mol%, 5 mol% to 65 mol%, 10 mol% to 70 mol%, 10 mol% to 65 mol%, 10 mol% to 60 mol%, 20 mol% to 65 mol%, 20 mol% to 55 mol%, 30 mol% to 65 mol%, 30 mol% to 60 mol%, 30 mol% to 55 mol%, 40 mol% to 65 mol%, 40 mol% to 60 mol%, 40 mol% to 55 mol%, or 40 mol% to 50% based on the total moles of the structural units of the copolymer (A). Within the above range, it is possible to control the reactivity of the copolymer (A) and increase its solubility, and as a result, the coatability of the photosensitive resin composition is significantly improved.

[0031] The copolymer (A) used in the present invention may have a weight average molecular weight of 500 Da to 50,000 Da, preferably 3,000 Da to 30,000 Da. When the weight average molecular weight is within the above range, the adhesion to the substrate is excellent, the physical and chemical properties are good, and the viscosity is appropriate.

[0032] The copolymer (A) used in the present invention can be synthesized by copolymerization known in the art. The content of the copolymer (A) can be in the range of 1% by weight to 80% by weight, 5% by weight to 80% by weight, 5% by weight to 70% by weight, 5% by weight to 60% by weight, 10% by weight to 80% by weight, 10% by weight to 70% by weight, 10% by weight to 60% by weight, 20% by weight to 80% by weight, 20% by weight to 70% by weight, 20% by weight to 60% by weight, 30% by weight to 80% by weight, 30% by weight to 70% by weight, 30% by weight to 60% by weight, 40% by weight to 80% by weight, 40% by weight to 70% by weight, 40% by weight to 60% by weight, 50% by weight to 80% by weight, 50% by weight to 70% by weight, or 50% by weight to 60% by weight, based on the total weight of the photosensitive resin composition excluding the remaining solvent. Within the above ranges, the pattern profile after development is favorable, with improved properties such as film retention and chemical resistance.

[0033] (B) Photopolymerizable compound The photopolymerizable compound (or monomer) used in the present invention is a compound that can be polymerized by the action of a photopolymerization initiator. It can include a monofunctional or polyfunctional ester compound of acrylic acid or methacrylic acid having at least one ethylenically unsaturated group. From the viewpoint of chemical resistance, it can be preferably a polyfunctional compound having at least two functional groups.

[0034] The polymerizable compound is ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, glycerin tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, monoester of pentaerythritol tri(meth)acrylate and succinic acid, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, acrylate, dipentaerythritol hexa(meth)acrylate, monoester of dipentaerythritol penta(meth)acrylate and succinic acid, caprolactone-modified dipentaerythritol hexa(meth)acrylate, pentaerythritol triacrylate-hexamethylene diisocyanate (reaction product of pentaerythritol triacrylate and hexamethylene diisocyanate), tripentaerythritol hepta(meth)acrylate, tripentaerythritol octa(meth)acrylate, bisphenol A epoxy acrylate, and ethylene glycol monomethyl ether acrylate, but are not limited thereto.

[0035] In addition, it may include, but is not limited to, polyfunctional urethane acrylate compounds obtained by reacting a compound having a linear alkylene group and an alicyclic structure with two or more isocyanate groups, and compounds having one or more hydroxyl groups and 3, 4, or 5 acryloyloxy groups and / or methacryloyloxy groups in the molecule.

[0036] Examples of commercially available photopolymerizable compounds include monofunctional (meth)acrylates such as Aronix M-101, M-111, and M-114 manufactured by Toagosei Co., Ltd., KAYARAD TC-110S and TC-120S manufactured by Nippon Kayaku Co., Ltd., and V-158 and V-2311 manufactured by Osaka Yuki Kagaku Kogyo Co., Ltd., difunctional (meth)acrylates such as Aronix M-210, M-240, and M-6200 manufactured by Toagosei Co., Ltd., KAYARAD HDDA, HX-220, and R-604 manufactured by Nippon Kayaku Co., Ltd., and V260, V312, and V335HP manufactured by Osaka Yuki Kagaku Kogyo Co., Ltd., and Aronix Examples of the functional (meth)acrylates having three or more functionalities include M-309, M-400, M-403, M-405, M-450, M-7100, M-8030, M-8060, and TO-1382 manufactured by Nippon Kayaku Co., Ltd.; KAYARAD TMPTA, DPHA, DPHA-40H, DPCA-20, DPCA-30, DPCA-60, and DPCA-120 manufactured by Nippon Kayaku Co., Ltd.; and V-295, V-300, V-360, V-GPT, V-3PA, and V-400 manufactured by Osaka Yuki Kagaku Kogyo Co., Ltd.

[0037] The photopolymerizable compound can be used alone or in combination with two or more of them. It can be used in an amount of 1 part by weight to 100 parts by weight, 10 parts by weight to 80 parts by weight, 20 parts by weight to 80 parts by weight, 20 parts by weight to 70 parts by weight, 30 parts by weight to 80 parts by weight, 30 parts by weight to 70 parts by weight, 40 parts by weight to 80 parts by weight, 40 parts by weight to 70 parts by weight, 50 parts by weight to 80 parts by weight, or 50 parts by weight to 70 parts by weight, based on 100 parts by weight of the copolymer (A) (based on solid content). Within the above range, high sensitivity with excellent pattern developability and film properties can be realized.

[0038] (C) Photopolymerization initiator The photoinitiators used in the present invention function to initiate the polymerization of monomers that can be cured by visible light, ultraviolet radiation, deep ultraviolet radiation, and the like.

[0039] The photopolymerization initiator may be a radical polymerization initiator, examples of which include, but are not limited to, at least one selected from the group consisting of acetophenone-based, benzophenone-based, benzoin-based, benzoyl-based, xanthone-based, triazine-based, halomethyloxadiazole-based, and lophine dimer-based photopolymerization initiators.

[0040] Specific examples thereof include 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), benzoyl peroxide, lauryl peroxide, t-butyl peroxypivalate, 1,1-bis(t-butylperoxy)cyclohexane, p-dimethylaminoacetophenone, 2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl)phenyl]-1-butanone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, benzyl dimethyl ketal, benzophenone, benzoin propyl ether, diethylthioxanthone, 2,4-bis(trichloromethyl)-6-p-methoxyphenyl-s-triazine, 2-trichloromethyl-5-styryl-1,3,4-oxodiazole, 9-methyl-1,3,4-di ... -phenylacridine, 3-methyl-5-amino-((s-triazin-2-yl)amino)-3-phenylcoumarin, 2-(o-chlorophenyl)-4,5-diphenylimidazolyl dimer, 1-phenyl-1,2-propanedione-2-(o-ethoxycarbonyl)oxime, 1-[4-(phenylthio)phenyl]-octane-1,2-dione-2-(o-benzoyloxime), o-benzoyl-4'-(benzmercapto)benzoylhexylketoxime, 2,4,6-trimethylphenylcarbonyl-diphenylphosphonyloxide, hexafluorophosphoro-trialkylphenylsulfonium salts, 2-mercaptobenzimidazole, 2,2'-benzothiazolyl disulfide, and mixtures thereof. In addition, the oxime compounds disclosed in (Patent Document 2), (Patent Document 3), (Patent Document 4), (Patent Document 5), (Patent Document 6), (Patent Document 7), (Patent Document 8), (Patent Document 9), (Patent Document 10), (Patent Document 11), (Patent Document 12), (Patent Document 13), and (Patent Document 14) can be used.

[0041] The photopolymerization initiator can be used in an amount of 0.1 parts by weight to 20 parts by weight, 0.1 parts by weight to 15 parts by weight, 1 parts by weight to 20 parts by weight, 1 parts by weight to 15 parts by weight, 1 parts by weight to 10 parts by weight, 1 parts by weight to 8 parts by weight, 1 parts by weight to 6 parts by weight, 1 parts by weight to 5 parts by weight, 2 parts by weight to 10 parts by weight, 2 parts by weight to 8 parts by weight, 2 parts by weight to 6 parts by weight, or 2 parts by weight to 5 parts by weight, based on 100 parts by weight of the copolymer (A) (based on the solid content). Within the above range, high sensitivity with excellent pattern developability and film properties can be achieved.

[0042] (D) Isocyanate compounds The isocyanate compound used in the present invention functions as an adhesion promoter. The -NCO group of the isocyanate compound has high reactivity and easily reacts with compounds having active hydrogen, such as hydroxyl groups, amine groups, carboxyl groups, epoxy groups, water, and acids. The crosslinking reaction caused by such a reaction can further enhance the adhesion between the insulating film and the substrate.

[0043] At the same time, it reacts with other components in the photosensitive resin composition, such as the copolymer (A) and the solvent (E), to form a colored three-dimensional polymer compound, so that the insulating film exhibits a color.

[0044] The isocyanate-based compound may be at least one selected from the group consisting of 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, allyl isocyanate, (trimethylsilyl)isocyanate, (R)-(-)-3-methyl-2-butylisocyanate, (R)-(+)-1-phenylpropyl isocyanate, (R)-(-)-2-heptyl isocyanate, hexyl isocyanate, butyl isocyanate, isopropyl isocyanate, cyclohexyl isocyanate, propyl isocyanate, octadecyl isocyanate, phenyl isocyanate, 2-isocyanatoethyl methacrylate, 2-isocyanatoethyl acrylate, 1,1-(bisacryloyloxyacetyl)isocyanate, ethyl isocyanurate, and 2-isocyanatoethyl acrylate.

[0045] In addition, it may further comprise a multifunctional isocyanate-based compound polymer.

[0046] For example, KBE-9007N from Shinetsu Co., Ltd. can be used as the isocyanate-based compound, and X-12-1159L from Shinetsu Co., Ltd. can also be used.

[0047] The isocyanate compound can be used in an amount of 0.01 to 5 parts by weight, 0.01 to 3 parts by weight, 0.1 to 5 parts by weight, 0.2 to 5 parts by weight, 0.1 to 3 parts by weight, or 0.2 to 3 parts by weight, based on 100 parts by weight (based on solid content) of the copolymer (A). Within the above range, an insulating film having excellent adhesion to the substrate and an (opaque) color can be obtained.

[0048] (E) Solvent The photosensitive resin composition of the present invention can be prepared as a liquid composition in which the above-mentioned components are mixed with a solvent. In such a case, the solvent can contain a cyclic ketone compound.

[0049] Specifically, the cyclic ketone compound may be at least one selected from the group consisting of cyclohexanone, cyclopentanone, and cyclobutanone, and may preferably be cyclopentanone.

[0050] The boiling point of the cyclic ketone compound may be from 70°C to 160°C, from 90°C to 150°C, or from 120°C to 140°C.

[0051] The cyclic ketone compounds function to impart color to the insulating film.

[0052] Specifically, cyclic ketones can form colored compounds through the aldol reaction in the presence of an acid catalyst. For example, cyclopentanone undergoes enolization, aldol addition, and dehydration to form the yellow colored 2-cyclopentylidenecyclopentan-1-one.

[0053] In addition, other solvents can be further used in the present invention as long as they are compatible with the components of the above photosensitive resin composition and they do not impair the effect of the present invention.

[0054] Examples of such solvents include ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate and ethylene glycol monoethyl ether acetate; propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, and propylene glycol monobutyl ether; propylene glycol dialkyl ethers such as propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, and propylene glycol dibutyl ether; dipropylene glycol dialkyl ethers such as dipropylene glycol dimethyl ether; propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, and propylene glycol monobutyl ether acetate; alkyl ether acetates, cellosolves such as ethyl cellosolve and butyl cellosolve, carbitols such as butyl carbitol, lactic acid esters such as methyl lactate, ethyl lactate, n-propyl lactate, and isopropyl lactate, aliphatic carboxylic acid esters such as ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-amyl acetate, isoamyl acetate, isopropyl propionic acid, n-butyl propionic acid, and isobutyl propionic acid, methyl 3-methoxypropionic acid, ethyl Examples of the solvent include, but are not limited to, esters such as 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methylpyruvate, and ethylpyruvate, aromatic hydrocarbons such as toluene and xylene, ketones such as 2-heptanone, 3-heptanone, and 4-heptanone, amides such as N-dimethylformamide, N-methylacetamide, N,N-dimethylacetamide, and N-methylpyrrolidone, lactones such as γ-butyrolactone, and mixtures thereof. The solvent may be used alone or in combination of two or more.

[0055] In the photosensitive resin composition according to the present invention, the content of the solvent is not particularly limited, but from the viewpoint of the coatability and stability of the photosensitive resin composition thus prepared, the solvent can be used so that the solid content is 5 wt% to 80 wt%, 5 wt% to 70 wt%, 5 wt% to 60 wt%, 10 wt% to 70 wt%, 10 wt% to 60 wt%, 10 wt% to 55 wt%, 10 wt% to 50 wt%, 10 wt% to 45 wt%, 10 wt% to 40 wt%, 10 wt% to 30 wt%, 20 wt% to 60 wt%, 20 wt% to 55 wt%, 20 wt% to 50 wt%, 20 wt% to 45 wt%, 20 wt% to 40 wt%, or 20 wt% to 30 wt%, based on the total weight of the composition.

[0056] Additionally, the solvent may contain a cyclic ketone compound in an amount of 1 wt% to 90 wt%, 1 wt% to 70 wt%, 1 wt% to 50 wt%, 1 wt% to 30 wt%, 5 wt% to 100 wt%, 5 wt% to 50 wt%, 5 wt% to 40 wt%, 5 wt% to 30 wt%, 5 wt% to 20 wt%, 7 wt% to 90 wt%, 7 wt% to 50 wt%, 10 wt% to 90 wt%, or 10 wt% to 50 wt%, based on the total weight of the solvent.

[0057] Within the above range, the compatibility with other components of the photosensitive resin composition is good, and the storage stability at room temperature or even low temperature is excellent. In addition, the solvent can remain in an appropriate amount at the pre-bake temperature when the insulating film is formed (at the time of coating), so that it can help the formation or smoothing of the coating film. Furthermore, it can evaporate sufficiently at a temperature of 70°C to 150°C to form a coating film at low temperature curing.

[0058] In addition, the photosensitive resin composition of the present invention may further contain other components to improve its properties. For example, the other components may include a surfactant (F) and / or a silane coupling agent (G).

[0059] (F) Surfactant The photosensitive resin composition of the present invention may further contain a surfactant, if necessary, in order to improve coatability and prevent the occurrence of defects.

[0060] The type of surfactant is not particularly limited. Preferably, it may include a fluorine-based surfactant, a silicone-based surfactant, a nonionic surfactant, etc. From the viewpoint of dispersibility, it is preferable to use BYK-307 of the above.

[0061] Examples of surfactants include BM-1000 and BM-1100 supplied by BM CHEMIE Co., Ltd., Megapack F142D, F172, F173, F183, F-470, F-471, F-475, F-482, and F-489 supplied by Dai Nippon Ink Chemical Kogyo Co., Ltd., Florad FC-135, FC-170C, FC-430, and FC-431 supplied by Sumitomo 3M Ltd., Sufron S-112, S-113, S-131, S-141, S-145, S-382, SC-101, SC-102, SC-103, SC-104, SC-105, and SC-106 supplied by Asahi Glass Co., Ltd., Shinakida Kasei Eftop EF301, 303, and 352 supplied by Toray Silicone Co.,Ltd.; SH-28 PA, SH-190, SH-193, SZ-6032, SF-8428, DC-57, and DC-190 supplied by Toray Silicone Co.,Ltd.; DC3PA, DC7PA, SH11PA, SH21PA, SH8400, FZ-2100, FZ-2110, FZ-2122, FZ-2222, and FZ-2233 supplied by Dow Corning Toray Silicone Co.,Ltd.; GE Toshiba Silicones Co.,Ltd.Examples of suitable surfactants include TSF-4440, TSF-4300, TSF-4445, TSF-4446, TSF-4460, and TSF-4452 supplied by BYK Corporation, and BYK-333 and BYK-307 supplied by BYK Corporation, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether, polyoxyethylene aryl ethers such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether, and polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate, as well as organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), (meth)acrylate copolymer Polyflow No. 57 and 95 (manufactured by Kyoei Yuji Chemical Co., Ltd.). They may be used alone or in combination of two or more of these.

[0062] The surfactant can be used in an amount of 0.0001 to 5 parts by weight, 0.0001 to 3 parts by weight, 0.001 to 5 parts by weight, 0.001 to 3 parts by weight, 0.001 to 3 parts by weight, 0.01 to 5 parts by weight, 0.01 to 3 parts by weight, 0.1 to 5 parts by weight, or 0.1 to 3 parts by weight, based on 100 parts by weight of the copolymer (A) (based on the solid content). Within the above range, the coating of the composition is carried out smoothly.

[0063] (G) Silane coupling agent In order to enhance adhesion to a substrate, the photosensitive resin composition of the present invention may further contain a silane coupling agent having at least one reactive group selected from the group consisting of a carboxyl group, a (meth)acryloyl group, an amino group, a mercapto group, a vinyl group, and an epoxy group.

[0064] The type of silane coupling agent is not particularly limited. It can be at least one selected from the group consisting of trimethoxysilylbenzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. Preferred is γ-glycidoxypropyltrimethoxysilane or γ-glycidoxypropyltriethoxysilane having an epoxy group, which can increase the film retention rate and has excellent adhesion to the substrate.

[0065] The silane coupling agent can be used in an amount of 0.0001 to 5 parts by weight, 0.0001 to 3 parts by weight, 0.001 to 5 parts by weight, 0.001 to 3 parts by weight, 0.001 to 3 parts by weight, 0.01 to 5 parts by weight, 0.01 to 3 parts by weight, 0.01 to 1 part by weight, 0.1 to 5 parts by weight, or 0.1 to 3 parts by weight, based on 100 parts by weight of the copolymer (A) (based on the solid content).Within the above range, the adhesion to the substrate is good.

[0066] In addition, the photosensitive resin composition of the present invention may further contain other additives such as antioxidants and stabilizers, so long as they do not adversely affect the physical properties of the photosensitive resin composition.

[0067] The photosensitive resin composition of the present invention can be cured at a relatively low temperature. Specifically, the curing temperature can be 70°C to 150°C, 100°C to 150°C, 100°C to 140°C, or 110°C to 130°C.

[0068] The present invention provides an insulating film (cured film) formed from a photosensitive resin composition.

[0069] The insulating film can be prepared by a method known in the art. For example, a photosensitive resin composition is coated on a substrate by a spin coating method in which the substrate is pre-baked at a temperature of 60°C to 130°C for 60 to 130 seconds to remove the solvent. The substrate is then exposed to light using a photomask having a desired pattern, and developed using a developer (e.g., a tetramethylammonium hydroxide (TMAH) solution) to form a pattern in the coating layer. Thereafter, if necessary, the patterned coating layer is post-baked at a temperature of 70 to 150°C for 10 minutes to 5 hours to prepare a desired insulating film.

[0070] The exposure is 10 mJ / cm2 in the wavelength range of 200 to 450 nm, with a wavelength of 365 nm as the reference. 2 ~100mJ / cm 2 According to the process of the present invention, it is possible to easily form a desired pattern from the viewpoint of process.

[0071] Coating of the photosensitive resin composition on a substrate can be performed, for example, to a desired thickness of 2 to 25 μm by a spin coating method, a slit coating method, a roll coating method, a screen printing method, an applicator method, or the like. In addition, as a light source used for exposure (irradiation), a low pressure mercury lamp, a high pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, an argon gas laser, or the like can be used. X-rays, electron beams, and the like can also be used if desired.

[0072] The photosensitive resin composition of the present invention can form an opaque (colored) insulating film that is excellent in heat resistance, solvent resistance, acid resistance, alkali resistance, film retention, hardness, and resolution.

[0073] For example, the insulating film may have a transmittance of 80% or less, 78% or less, or 70% or less at a wavelength of 400 nm (see Evaluation Example 3).

[0074] Therefore, the insulating film of the present invention thus formed has excellent physical properties such as resolution without surface roughness and hardness when it is subjected to heat treatment, immersed in a solvent, acid, base, etc., or contacted with a solvent, acid, base, etc. Thus, the insulating film can be effectively used as a planarizing film for a thin film transistor (TFT) substrate of a liquid crystal display or an organic electroluminescence display, a partition of an organic electroluminescence display, an interlayer insulator of a semiconductor device, a core or clad material of an optical waveguide, etc.

[0075] EMBODIMENTS FOR CARRYING OUT THEINVENTION The present invention will now be described in more detail with reference to the following examples, which are provided to illustrate the present invention and are not intended to limit the scope of the present invention thereto.

[0076] In the preparative examples which follow, weight average molecular weights are determined by gel permeation chromatography (GPC, eluent: tetrahydrofuran) referenced to polystyrene standards. EXAMPLES

[0077] Preparation Example 1: Preparation of Copolymer (A) In a 500 ml round-bottom flask equipped with a reflux condenser and a stirrer, 40 g of a monomer mixture consisting of 50 mol% styrene, 22 mol% methacrylic acid, 10 mol% glycidyl methacrylate, and 18 mol% 3,4-epoxycyclohexylmethyl methacrylate was placed together with 120 g of methyl 3-methoxypropionate (MMP) as a solvent and 2 g of 2,2'-azobis(2,4-dimethylvaleronitrile) as a radical polymerization initiator. The temperature was then raised to 70°C and stirred for 8 hours to obtain a copolymer (A) solution having a solid content of 33 wt%. The copolymer (A) thus prepared had a weight average molecular weight of 7,000 Da.

[0078] Examples and Comparative Examples: Preparation of Photosensitive Resin Composition The components used in the following examples and comparative examples are as follows.

[0079] [Table 1]

[0080] Example 1 100 parts by weight of the copolymer (A) prepared in Preparation Example 1, 66.7 parts by weight of hexafunctional dipentaerythritol hexaacrylate as a photopolymerizable compound, 5.2 parts by weight of OXE-02 (C) as a photopolymerization initiator, 0.9 parts by weight of 3-isocyanatepropyltriethoxysilane as an isocyanate-based compound (D), and 1.7 parts by weight of a surfactant (F) were mixed. Here, the content of each is based on the solid content excluding the solvent. Then, cyclopentanone (E-1) was added to the mixture so that the solid content of the mixture was 21% by weight. The resultant was mixed using a shaker for 2 hours to prepare a liquid-phase photosensitive resin composition.

[0081] Examples 2 and 3 and Comparative Examples 1 and 2 Each photosensitive resin composition solution was prepared in the same manner as in Example 1, except that the type and / or content of each component was changed as shown in Table 2 below.

[0082] [Table 2]

[0083] [Evaluation example] The insulating films were prepared from the photosensitive resin compositions obtained in Examples 1 to 3 and Comparative Examples 1 and 2. The film retention, pencil hardness, transmittance, and resolution of the insulating films were evaluated, and the results are shown in Table 3 below.

[0084] [Preparation of insulating film] The photosensitive resin compositions obtained in the examples and comparative examples were each coated on a glass substrate using a spin coater and prebaked at 100°C for 60 seconds to form a coated film. A mask was placed on the thus-formed coated film so that a 5 cm x 5 cm area of ​​the coated film was 100% exposed and the gap with the substrate was maintained at 25 μm. Thereafter, the film was irradiated with light having a wavelength of 200 nm to 450 nm at 30 mJ / cm2 based on a wavelength of 365 nm using an aligner device (model name: MA6) that emits light having a wavelength of 200 nm to 450 nm. 2 The film was exposed to light for a certain period of time at an exposure dose of 100 nm. The exposed film was developed in an aqueous developer of 2.38 wt % tetramethylammonium hydroxide (TMAH) at 23°C until the unexposed areas were completely washed away. The exposed film with the pattern formed was heated (post-baked) in an oven at 130°C for 1 hour to obtain an insulating film with a thickness of 2.5 (±0.2) μm.

[0085] Evaluation example 1: Film retention rate The initial thickness at pre-bake was measured according to the dielectric film preparation process. After the dielectric film preparation process, it was developed with an aqueous solution of TMAH diluted to 2.38 wt % at 23°C. It was cured at 130°C for 1 hour and the thickness was measured. The film retention was obtained by calculating the ratio in percentage of the final dielectric film thickness to the film thickness at pre-bake.

[0086] Evaluation example 2: Pencil hardness An insulating film with a total thickness of 2.5 (±0.2) μm at the time of final curing was prepared according to the insulating film preparation process. Using a pencil hardness tester, a 500 g weight was applied in the same direction at a constant speed and angle (45°) to observe the degree of damage to the insulating film using Mitsubishi UNI pencils ranging from 6B to 9H.

[0087] Evaluation example 3: Transmittance (ultraviolet-visible) According to the preparation process of the insulating film, a preliminary insulating film having a thickness of 2.5 μm was formed on a glass substrate. The transmittance was measured by the following method.

[0088] The transmittance was measured by scanning the wavelength range from 200 nm to 800 nm using an ultraviolet / visible spectrometer (Varian UV spectrometer) and measuring the transmittance at a wavelength of 400 nm. The lower the transmittance at a wavelength of 400, the better.

[0089] Evaluation example 4: Resolution (lithography performance) The compositions prepared in the examples and comparative examples were each uniformly coated on a glass substrate by spin coating, and then dried for 1 minute on a hot plate maintained at 100°C to form a substrate. A negative mask having an opening pattern with a line width of 30 μm was placed on the substrate on which the dried film was to be formed. Then, an aligner device (model name: MA6) was used to apply 30 mJ / cm 2 The film was exposed to light at an exposure dose of 1000 nm and developed at 23°C with an aqueous solution of TMAH diluted to 2.38% by weight until the unexposed areas were completely washed away. The exposed film with the pattern formed thereon was then post-baked in an oven at 130°C for 1 hour to obtain an insulating film with a thickness of 2.5 (±0.2) μm. For the substrate on which the insulating film was formed, the line width at the bottom of the pattern was measured using a non-contact thickness meter (SIS-2000, SNU), and the resolution was evaluated according to the following criteria. The bottom line was open with a width of 20 μm or more. The bottom line was open with a width of less than 20 μm.

[0090] [Table 3]

[0091] As can be seen from Table 3, the insulating films obtained from the compositions of the Examples, which are within the scope of the present invention, were generally superior in terms of film retention, pencil hardness, and resolution at the desired level of transmittance. In contrast, the insulating films obtained from the compositions of Comparative Examples 1 and 2, which are outside the scope of the present invention, had lower film retention and resolution than the insulating films prepared in the Examples, and were unable to achieve the desired level of transmittance.

Claims

1. (A) a copolymer; (B) a photopolymerizable compound; (C) a photopolymerization initiator; and (D) an isocyanate compound; (E) a solvent comprising cyclopentanone; A photosensitive resin composition comprising:

2. 2. The photosensitive resin composition according to claim 1, wherein the copolymer (A) comprises (a1) a structural unit derived from an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride, or a combination thereof, (a2) a structural unit derived from an ethylenically unsaturated compound containing an epoxy group, and (a3) ​​a structural unit derived from an ethylenically unsaturated compound different from (a1) and (a2).

3. The structural unit (a2) includes (a2-1) a structural unit derived from an unsaturated monomer containing an alicyclic epoxy group represented by the following formula 1, and (a2-2) a structural unit derived from an unsaturated monomer containing an acyclic epoxy group represented by the following formula 2: 【Chemistry 1】 (In the above formula, R ２ and R ４ are each independently hydrogen or C １－４ alkyl, R １ and R ３ are each independently １－４ The photosensitive resin composition according to claim 2, wherein the alkylene is an alkylene.

4. The photosensitive resin composition according to claim 3, wherein the total content of the structural units (a2-1) and (a2-2) is in the range of 10 mol % to 50 mol % based on the total number of moles of the structural units of the copolymer (A).

5. 4. The photosensitive resin composition according to claim 3, wherein the molar ratio of the structural units (a2-1) and (a2-2) is 50 to 99:50 to 1.

6. The photosensitive resin composition according to claim 1, wherein the isocyanate compound is at least one selected from the group consisting of 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, allyl isocyanate, (trimethylsilyl)isocyanate, (R)-(-)-3-methyl-2-butylisocyanate, (R)-(+)-1-phenylpropyl isocyanate, (R)-(-)-2-heptyl isocyanate, hexyl isocyanate, butyl isocyanate, isopropyl isocyanate, cyclohexyl isocyanate, propyl isocyanate, octadecyl isocyanate, phenyl isocyanate, 2-isocyanatoethyl methacrylate, 2-isocyanatoethyl acrylate, 1,1-(bisacryloyloxyacetyl)isocyanate, ethyl isocyanurate, and 2-isocyanatoethyl acrylate.

7. 2. The photosensitive resin composition according to claim 1, wherein the solvent (E) comprises the cyclopentanone in an amount of 5% by weight to 100% by weight, based on the total weight of the solvent (E).

8. The photosensitive resin composition according to claim 1, which has a curing temperature of 70°C to 150°C.

9. A method for preparing an insulating film from the photosensitive resin composition according to claim 1.

10. The method of claim 9, wherein the insulating film has a transmittance of 80% or less at a wavelength of 400 nm.

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