TWI497205B - A photosensitive resin composition, a protection film and spacer of liquid crystal dispaly panel, and a method for fabricating the same - Google Patents

Description

Photosensitive resin composition, protective film for liquid crystal display panel, spacer, method of forming the same, and liquid crystal display panel

The present invention relates to a photosensitive resin composition, a protective film for a liquid crystal display panel, a spacer, and a liquid crystal display panel having the same, and more particularly to use as a liquid crystal display panel such as a liquid crystal display panel or a touch panel. A photosensitive resin composition of a material of a protective film and a spacer, a protective film for a liquid crystal display panel formed of the composition, a spacer, and a liquid crystal display panel having the protective film and the spacer.

A radiation device such as an LCD or a CCD is immersed in a display element with a solvent, an acid or an alkali solution, etc., and when the wiring electrode layer is formed by sputtering, the surface of the element is locally subjected to a high temperature. Thus, in order to prevent deterioration or damage of the components caused by such treatment, a protective film formed of a film resistant to these treatments is provided on the surface of the member.

Such a protective film is required to have a high adhesion to a layer formed on a substrate or a lower layer and a protective film to form the protective film, the film itself is smooth and high in strength, and has transparency, heat resistance and light resistance. After a long period of time, coloring, yellowing, whitening, and the like do not occur, and water resistance, solvent resistance, acid resistance, and alkali resistance are excellent. As a material which forms a protective film satisfying such characteristics, for example, a photosensitive resin composition containing a polymer having a glycidyl group is known (see Patent Document 1).

When such a protective film is used as a protective film of a color liquid crystal display device or a color filter of a charge coupled device, the protective film is generally required to have high transparency.

[Patent Document 1] Japanese Patent No. 3101986

Further, in the liquid crystal display panel, in order to maintain a constant interval (cell gap) between the two substrates, spacer particles such as glass beads or plastic beads having a predetermined particle diameter have been conventionally used, but since these spacer particles are absent Since it is spread on a transparent substrate such as a glass substrate, when spacer particles are present in the element formation region, the spacer particles are reflected and the incident light is scattered to lower the contrast of the liquid crystal panel. Therefore, in order to solve these problems, a method of forming a spacer by photolithography is employed. In this method, a photosensitive resin composition is applied onto a substrate, exposed to ultraviolet light through a predetermined mask, and then developed to form a dot-like or stripe-shaped spacer, since it can be specified only outside the formation region of the primitive. The portion forms a spacer, thus substantially solving the above problem.

In the step of forming these protective films and spacers, from the viewpoint of production cost, there is a demand for a photosensitive resin composition which can be used under the same technical conditions in the same variety. In this case, it is necessary to have a photosensitive resin composition which sufficiently satisfies the adhesion, transparency, heat resistance, and the resolution and compression characteristics necessary for the spacer material.

In addition, in recent years, the size of the mother glass substrate has been increased from about 680×880 mm to about 1870×2200 mm due to the increase in the area of the liquid crystal display element and the improvement in productivity. In the step of forming the protective film or the spacer, the protective film or the spacer-forming photosensitive resin composition is usually applied onto a transparent substrate, and the solvent is removed by baking on a hot plate, and then exposed and developed to form a protective layer. Membranes and spacers. However, as the substrate is enlarged, the photopolymerization initiator component in the photosensitive resin composition is sublimated at the time of formation of the protective film and the spacer, and the problem of contaminating the baking furnace and the photomask may cause a decrease in production speed and production cost. rise.

Further, the applicant discloses in Patent Document 2 that by using 1-(2-bromo-4-morpholinylphenyl)-2-benzyl-2-dimethylaminobutane-1-one or 1-( A brominated acetophenone photopolymerization initiator such as 3-bromo-4-morpholinylphenyl)-2-benzyl-2-dimethylaminobutan-1-one, which can reduce the photosensitive polymerization initiator component Sublimation causes contamination of the baking oven and the exhaust pipe and clogging of the filtering device provided in the developing line when the developing liquid is repeatedly used.

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2001-235617

In this case, the protective film of the photosensitive polymerization initiator component of the photosensitive resin composition used for the formation of a spacer, which is described in the patent document 2, is not sufficient from the viewpoint of transparency. Therefore, it is also desired to use a photosensitive resin which is required to have a non-sublimation-sensitive photopolymerization initiator component and which has sufficient adhesion, transparency, heat resistance, and resolution and compression characteristics necessary for the spacer material. Composition.

An object of the present invention is to provide a coating having a sufficient range of processes and capable of suppressing contamination of a baking furnace, a photomask, and the like caused by sublimation of a photopolymerization initiator component, and having sufficient adhesion, transparency, and heat resistance for a protective film material. A photosensitive resin composition having a resolution and a compression property necessary for the spacer material, a protective film and a spacer formed therefrom, a method of forming the same, and a liquid crystal display panel having the protective film and the spacer.

According to the present invention, the first object relates to a photosensitive resin composition comprising [A] (a1) an ethylenically unsaturated carboxylic acid and/or an ethylenically unsaturated carboxylic anhydride and (a2) other ethylenicity. a copolymer of an unsaturated compound, [B] a polymerizable compound having an ethylenically unsaturated bond, and [C] a photopolymerization initiator composed of a compound represented by the following formula (1),

[In the formula (1), n is an integer of 2 to 12, and R ₁ represents hydrogen, a hydroxyl group, or any group having a structure represented by each of the following (I), (II) or (III), (III) R ₂ is an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, or a phenyl group (wherein at least one or more alkyl groups having 1 to 6 carbon atoms may be optionally contained) Substituted by an alkoxy group having 1 to 6 carbon atoms)].

Second, the present invention relates to a photosensitive resin composition for forming a protective film for a liquid crystal display panel and a spacer which is composed of the photosensitive resin composition as described above.

Thirdly, the present invention relates to a protective film or spacer for a liquid crystal display panel formed of the photosensitive resin composition as described above.

Fourthly, the present invention relates to a method for forming a protective film or a spacer for a liquid crystal display panel, characterized in that it comprises at least the following steps (1) to (4), and (1) forming the photosensitive resin composition on the substrate is a step of coating a film, (2) a step of exposing at least a portion of the coating film, (3) a step of developing the film after exposure, and (4) a film after the image is developed. The step of heating.

Fifth, the present invention relates to a liquid crystal display panel having the above protective film or spacer for a liquid crystal display panel of the present invention.

The photosensitive resin composition of the present invention has a sufficient range of processes, and can suppress contamination of a baking furnace, a photomask, and the like caused by sublimation of a photopolymerization initiator component, and has sufficient adhesion and transparency necessary for a protective film material. A photosensitive resin composition having a resolution and a compression property necessary for heat resistance and a spacer material.

Hereinafter, each component of the protective film and the spacer-forming photosensitive resin composition (hereinafter simply referred to as "photosensitive resin composition") of the present invention will be described in detail.

-copolymer [A]-

The component [A] in the photosensitive resin composition of the present invention can be produced by radically polymerizing the compound (a1) and the compound (a2) in a solvent in the presence of a polymerization initiator.

Each component constituting the copolymer [A] is (a1) an ethylenically unsaturated carboxylic acid and/or an ethylenically unsaturated carboxylic anhydride (hereinafter, collectively referred to as "unsaturated carboxylic acid monomer (a1)"), Examples thereof include monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, 2-methylpropenyloxyethyl succinate, and 2-methylpropenyloxyethyl hexahydrophthalate; Malay Dicarboxylic acids such as acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid, acid anhydrides of the above dicarboxylic acids, and the like.

Among these unsaturated carboxylic acid monomers (a1), acrylic acid, methacrylic acid, maleic anhydride, and hexahydroortene are preferred from the viewpoints of copolymerization reactivity, solubility of the obtained copolymer to an aqueous alkali solution, and easy availability. 2-methacryloxyethyl phthalate or the like.

In the copolymer [A], the unsaturated carboxylic acid monomers (a1) may be used singly or in combination of two or more kinds.

In the copolymer [A], the content ratio of the repeating unit derived from the unsaturated carboxylic acid monomer (a1) is preferably from 5 to 50% by weight, more preferably from 10 to 40% by weight, particularly preferably 15~30% by weight. In this case, if the content ratio of the repeating unit derived from the unsaturated carboxylic acid monomer (a1) is less than 5% by weight, the solubility in the aqueous alkali solution tends to be small, and on the other hand, if it exceeds 40% by weight, it exists. The solubility in the aqueous alkali solution is too large.

Further, examples of the (a2) other ethylenically unsaturated compound (hereinafter simply referred to as "other monomer") include alkyl acrylates such as methyl acrylate and isopropyl acrylate; methyl methacrylate and methyl group. Ethyl acrylate, n-butyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, and the like, alkyl methacrylates; cyclohexyl acrylate, 2-methylcyclohexyl acrylate, Tricyclo[5.2.1.0 ^{2 , 6} ]decane-8-yl acrylate, 2-(tricyclo[5.2.1.0 ^{2 , 6} ]decane 8-yloxy)ethyl acrylate, isobornyl acrylate, etc. Acrylate cyclic esters; cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, tricyclo [5.0.1.02 ^{2 , 6} ]decane-8-yl methacrylate, methacrylic acid 2 - (tricyclo[5.2.1.0 ^{2 , 6} ]decane-8-yloxy)ethyl ester, isobornyl methacrylate, etc.; methacrylate alicyclic ester; phenyl acrylate, benzyl acrylate, etc. Aryl acrylate or aralkyl ester; aryl methacrylate or methacrylate such as phenyl methacrylate or benzyl methacrylate Aralkyl acrylates; dialkyl maleate, diethyl fumarate, diethyl itaconate, dialkyl esters; 2-hydroxyethyl methacrylate, methyl Hydroxyalkyl methacrylates such as 2-hydroxypropyl acrylate; tetrahydrofurfuryl methacrylate, tetrahydrofuranyl methacrylate, tetrahydrofuran-2-methyl methacrylate, etc. Five- and six-membered heterocyclic methacrylates; glycidyl acrylate, 2-methylglycidyl acrylate, 3,4-epoxybutyl acrylate, 6,7-epoxyheptyl acrylate Acrylic alkyl acrylates such as 3,4-epoxycyclohexyl acrylate; glycidyl methacrylate, 2-methyl glycidyl methacrylate, 3,4-epoxy methacrylate Ethylene glycol methacrylates such as esters, 6,7-epoxyheptyl methacrylate, 3,4-epoxycyclohexyl methacrylate; α-ethyl methacrylate, α - glycidyl propyl acrylate, glycidyl α-n-butyl acrylate, α-ethyl acrylate Α-alkyl acrylate epoxyalkyl esters such as 6,7-epoxyheptyl ester; o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinyl benzyl Glycidyl ethers such as glycidyl ether; 3-(methacryloxymethyl)oxetane, 3-(methacryloxymethyl)-2-trifluoromethyloxy Heterocyclobutane, 3-(methacryloxymethyl)-2-phenyloxetane, 2-(methacryloxymethyl)oxetane, 2-(A) Oxetane alkyl methacrylates such as acryloxymethyl)-4-trifluoromethyloxetane; styrene, α-methylstyrene, m-methylstyrene , vinyl aromatic compounds such as p-methylstyrene and p-methoxystyrene; phenyl maleimide, cyclohexylmaleimide, benzyl maleimide, N-amber Imino-3-maleimidobenzoate, N-succinimide-4-ma. lysine butyrate, N-succinimide-6-Malay醯iminohexanoate, N-succinimide-3-maleimido Propionate, N-(9-acridinyl) maleimide and other dicarboxylic acid quinone imine derivatives; 1,3-butadiene, isoprene, 2,3-dimethyl- A conjugated diene compound such as 1,3-butadiene, or acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, vinyl chloride, vinylidene chloride or vinyl acetate.

Among these other monomers, from the viewpoint of copolymerization reactivity and solubility of the obtained copolymer to an aqueous alkali solution, 2-methylcyclohexyl acrylate, hydroxyethyl methacrylate, and methacrylic acid tricyclo[ 5.2.1.0 ^{2 . 6} ]decane-8-yl ester, styrene, glycidyl methacrylate, 3-(methacryloxymethyl)-3-ethyloxetane, A Tetrahydrofurfuryl acrylate, 1,3-butadiene, phenyl maleimide, cyclohexane maleimide, and the like.

In the copolymer [A], the other monomers may be used singly or in combination of two or more kinds.

The copolymer [A] used in the present invention preferably contains 5 to 95% by weight, more preferably 10 to 90% by weight, particularly preferably 15 to 85% by weight, of the repeating unit derived from the compound (a2). In this case, when the repeating unit is less than 5% by weight, the storage stability of the copolymer [A] tends to be low. On the other hand, when it exceeds 95% by weight, the copolymer [A] is hardly soluble in the aqueous alkali solution.

As described above, the copolymer [A] used in the present invention has a carboxyl group and/or a carboxylic anhydride group and other ethylenically unsaturated compounds, and thus has an appropriate solubility to an aqueous alkali solution, and at the same time, even if a special curing agent is not used in combination. It can also be easily cured by heating.

The photosensitive resin composition containing the above copolymer [A] exhibits good alkali solubility at the time of development, and it is easy to form a spacer of a fixed pattern.

The solvent used in the preparation of the copolymer [A] may, for example, be an alcohol, an ether, a glycol ether, an ethylene glycol alkyl ether acetate, a diethylene glycol, a dipropylene glycol, a propylene glycol monoalkyl ether or a propylene glycol. Alkyl ether acetate, propylene glycol alkyl ether propionate, aromatic hydrocarbon, ketone, ester, and the like.

Specific examples thereof include the following: examples of the alcohol include methanol, ethanol, benzyl alcohol, 2-phenylethanol, and 3-phenyl-1-propanol; and examples of the ether include tetrahydrofuran; Examples of the glycol ether include ethylene glycol monomethyl ether and ethylene glycol monoethyl ether; and examples of the ethylene glycol alkyl ether acetate include methyl cellosolve acetate and ethyl cellosolve. And acetic acid ester, ethylene glycol monobutyl ether acetate, ethylene glycol monoethyl ether acetate, etc.; as diethylene glycol, for example, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, two Glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, etc.; as dipropylene glycol, for example, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, one Dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, diethylene glycol ethyl ether, etc.; as the propylene glycol monoalkyl ether, for example, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether , propylene glycol monobutyl ether, etc.; as propylene glycol alkyl ether acetate, Examples thereof include propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol butyl ether acetate, and the like; and examples of the propylene glycol alkyl ether propionate include propylene glycol methyl group. Ethyl acetate, propylene glycol ethyl ether propionate, propylene glycol propyl ether propionate, propylene glycol butyl ether propionate, etc., and examples of the aromatic hydrocarbon include toluene and xylene; and examples of the ketone include ketone. Methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, etc.; examples of the ester include methyl acetate, ethyl acetate, propyl acetate, butyl acetate, and 2-hydroxyl group. Ethyl propionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, methyl hydroxyacetate, ethyl hydroxyacetate, butyl glycolate, methyl lactate, Ethyl lactate, propyl lactate, butyl lactate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, propyl 3-hydroxypropionate, butyl 3-hydroxypropionate, 2-hydroxy-3- Methyl methyl butyrate, methyl methoxyacetate, ethyl methoxyacetate, propyl methoxyacetate , butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, propyl ethoxyacetate, butyl ethoxyacetate, methyl propoxyacetate, ethyl propoxyacetate, Propyl propoxy propyl acetate, butyl oxyacetate, methyl butoxyacetate, ethyl butoxyacetate, propyl butoxyacetate, butyl butoxyacetate, 3-methoxybutyl acetate , methyl 2-methoxypropionate, ethyl 2-methoxypropionate, propyl 2-methoxypropionate, butyl 2-methoxypropionate, methyl 2-ethoxypropionate Ethyl 2-ethoxypropionate, propyl 2-ethoxypropionate, butyl 2-ethoxypropionate, methyl 2-butoxypropionate, ethyl 2-butoxypropionate , propyl 2-butoxypropionate, butyl 2-butoxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate , 3-methoxypropionic acid butyl ester, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, propyl 3-ethoxypropionate, butyl 3-ethoxypropionate , methyl 3-propoxypropionate, ethyl 3-propoxypropionate, propyl 3-propoxypropionate, 3-propoxy Butyl propionate, methyl 3-butoxypropionate, ethyl 3-butoxypropionate, propyl 3-butoxypropionate, butyl 3-butoxypropionate, and the like.

Among them, preferred are ethylene glycol alkyl ether acetate, diethylene glycol, dipropylene glycol, propylene glycol monoalkyl ether, and propylene glycol alkyl ether acetate, of which diethylene glycol dimethyl is particularly preferred. Ether, diethylene glycol ethyl methyl ether, dipropylene glycol dimethyl ether, dipropylene glycol ethyl methyl ether, propylene glycol methyl ether, propylene glycol methyl ether acetate, 3-methoxybutyl acetate ester.

These solvents may be used singly or in combination of two or more kinds.

The amount of the solvent to be used is usually 50 to 90 parts by weight, preferably 55 to 85 parts by weight, based on 100 parts by weight of the total of the above (a1) and (a2).

In addition, the radical polymerization initiator to be used in the above polymerization is not particularly limited, and examples thereof include 2,2'-azobisisobutyronitrile and 2,2'-azobis (2,4). - dimethyl valeronitrile), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), 4,4'-azobis(4-cyanovaleric acid) , azo such as dimethyl 2,2'-azobis(2-methylpropionate) or 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) a compound; an organic peroxide such as benzamidine peroxide, lauric acid peroxide, t-butyl peroxypivalate, 1,1-di(tert-butylperoxy)cyclohexane; hydrogen peroxide or the like. Further, when a peroxide is used as the radical polymerization initiator, it can also be used as a redox type initiator in combination with a reducing agent.

These radical polymerization initiators may be used singly or in combination of two or more kinds.

The amount of the radical polymerization initiator to be used is usually 0.1 to 10.0 parts by weight, preferably 1.0 to 8.0 parts by weight, based on 100 parts by weight of the total of the above (a1) and (a2).

Further, in the above radical polymerization, the polymerization temperature is usually 60 to 100 ° C, preferably 70 to 90 ° C, and the polymerization time is usually 2 to 6 hours, preferably 3 to 5 hours.

The copolymer [A] thus obtained can be directly supplied to the photosensitive resin composition for preparation, and can be supplied from the solution and then supplied to the photosensitive resin composition.

The copolymer [A] has a polystyrene-equivalent weight average molecular weight (hereinafter referred to as "Mw") measured by gel permeation chromatography (GPC), and is usually from 2,000 to 100,000, preferably from 5,000 to 50,000. In this case, when Mw is less than 2,000, the developed film has a small developing property, a residual film ratio, and the like, and the shape, heat resistance, and the like of the pattern may be impaired. On the other hand, if it exceeds 100,000, the resolution is small. The shape of the pattern may be damaged.

- polymerizable compound [B]-

The component [B] in the photosensitive resin composition of the present invention is a polymerizable compound having an ethylenically unsaturated bond (hereinafter referred to as "polymerizable compound [B]").

The polymerizable compound [B] is not particularly limited, and the monofunctional, difunctional or trifunctional or higher (meth) acrylate has good polymerizability, and is preferably from the viewpoint of improving the strength of the obtained spacer. of.

Examples of the monofunctional (meth) acrylates include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, diethylene glycol monoethyl acrylate, and diethylene glycol monoethyl methacrylate. Isobornyl acrylate, isobornyl methacrylate, 3-methoxybutyl acrylate, 3-methoxybutyl methacrylate, 2-propenyloxyethyl-2-hydroxypropyl phthalate Ester, 2-methylpropenyloxyethyl-2-hydroxypropyl phthalate, and the like. In addition, general commercially available products, for example, ARONIXM-101, ARONIXM-111, ARONIXM-114 (manufactured by Toago Corporation); KAYARAD TC-110S, KAYARAD TC-120S (manufactured by Nippon Kayaku Co., Ltd.); biscird158, biscord2311 ( Osaka Organic Chemical Industry).

Further, examples of the difunctional (meth) acrylate include ethylene glycol diacrylate, ethylene glycol di(methacrylate), diethylene glycol diacrylate, and diethylene glycol di(methyl). Acrylate), tetraethylene glycol diacrylate, tetraethylene glycol di(methacrylate), 1,6-hexanediol diacrylate, 1,6-hexanediol di(methacrylate), 1, 9-decanediol diacrylate, 1,9-nonanediol di(methacrylate), bis(phenoxyethanol)phosphonium diacrylate, bis(phenoxyethanol)phosphonium di(methacrylate) )Wait. In addition, as a commercial item, for example, ARONIXM-210, ARONIXM-240, ARONIXM-6200 (manufactured by Toagosei Co., Ltd.); KAYARAD HDDA, KAYARAD HX-220, KAYARAD R-604 (Japan Chemicals Co., Ltd.) can be cited. System); biscord260, biscord312, biscord335HP (made by Osaka Organic Chemical Industry).

Further, examples of the trifunctional or higher (meth) acrylate include trimethylolpropane triacrylate, trimethylolpropane tri(methacrylate), pentaerythritol triacrylate, and pentaerythritol III ( Methacrylate, pentaerythritol tetraacrylate, pentaerythritol tetra(methacrylate), dipentaerythritol pentaacrylate, dipentaerythritol penta (methacrylate), dipentaerythritol hexaacrylate, dipentaerythritol hexa(methacrylate) ), tris(2-propenyloxyethyl)phosphate, tris(2-methylpropenyloxyethyl)phosphate, and the like.

In particular, the hexa-functional or higher-functional (meth) acrylate includes a compound having an alkylene linear and alicyclic structure and containing two or more isocyanate groups, and a trifunctional or tetrafunctional group having one or more hydroxyl groups in the molecule. A urethane acrylate compound obtained by reacting a pentafunctional (meth) acrylate compound.

Examples of the commercially available product include ARONIXM-309, ARONIXM-400, ARONIXM-405, ARONIXM-450, ARONIXM-7100, ARONIXM-8030, ARONIXM-8060, and ARONIXTO-1450 (manufactured by Toagosei Co., Ltd.); KAYARAD TMPTA, KAYARAD DPHA, KAYARAD DPCA-20, KAYARAD DPCA-30, KAYARAD DPCA-60, KAYARAD DPCA-120 (made by Nippon Kayaku Co., Ltd.); biscord295, biscord300, biscord360, biscordGPT, biscord3PA, biscord400 (Osaka Organic Chemistry) Industrial manufacturing). As a commercially available product of a ninth or more functional polyfunctional urethane acrylate, for example, newprolipo R-1150 (above, manufactured by Daiichi Kogyo Co., Ltd.) KAYARAD DPHA-40H (manufactured by Nippon Kayaku Co., Ltd.) )Wait.

Among these monofunctional, difunctional or trifunctional or higher (meth) acrylates, a trifunctional or higher (meth) acrylate is more preferable, and trimethylolpropane triacrylate and pentaerythritol are particularly preferable. Triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate.

The above-mentioned monofunctional, difunctional or trifunctional or higher (meth) acrylates may be used singly or in combination of two or more kinds.

In the photosensitive resin composition of the present invention, the amount of the polymerizable compound [B] is preferably 50 to 200 parts by weight, more preferably 60 to 150 parts by weight based on 100 parts by weight of the copolymer [A]. Share. In this case, when the amount of the polymerizable compound [B] is less than 50 parts by weight, a development residue may be generated during development, and on the other hand, if it exceeds 200 parts by weight, the resulting spacer adhesion tends to be small.

-Photopolymerization initiator [C]-

The compound represented by the above formula (1) (hereinafter referred to as "compound 1") as the [C] component in the photosensitive resin composition of the present invention is an essential component.

In the formula (1), n is an integer of 2 to 12, and R ₁ represents hydrogen, a hydroxyl group, or any group having a structure represented by each of the above (I), (II) or (III), and (III) R ₂ is an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, or a phenyl group (wherein at least one or more alkyl groups having 1 to 6 carbon atoms may be optionally contained; Substituted by an alkoxy group having 1 to 6 carbon atoms).

Here, examples of the alkyl group having 1 to 12 carbon atoms and the cycloalkyl group having 3 to 8 carbon atoms of R ₂ include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, and a n-butyl group. , isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-decyl, n-decyl, n-undecyl, n-dodecyl, cyclopentyl Base, cyclohexyl and the like.

Further, the alkyl group having 1 to 6 carbon atoms and the alkoxy group having 1 to 6 carbon atoms which are substituted on the phenyl group, and the alkyl group having 1 to 6 carbon atoms may, for example, be a methyl group or an ethyl group. Examples of the n-propyl group, the isopropyl group, the n-butyl group, the isobutyl group, the sec-butyl group, the t-butyl group, the n-pentyl group, the n-hexyl group, or the alkoxy group having 1 to 6 carbon atoms may, for example, be a methoxy group. Ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy and the like.

Specific examples of the compound (1) which is preferred in the present invention include 2-methyl-1-[4-(ethylthio)phenyl]-2-morpholinylpropan-1-one, 2 -methyl-1-[4-(n-propylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(isopropylthio)phenyl ]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(n-butylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl- 1-[4-(isobutylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(tert-butylthio)phenyl]-2- Morpholinylpropan-1-one, 2-methyl-1-[4-(n-pentylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4 -(n-hexylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(n-heptylthio)phenyl]-2-morpholinylpropane- 1-ketone, 2-methyl-1-[4-(n-octylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(positive Alkylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(2-hydroxyethyl) Thio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(3-hydroxypropylthio)phenyl]-2-morpholinylpropane-1- Ketone, 2-methyl-1-[4-(4-hydroxybutylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(5-hydroxyl) Heptylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(5-hydroxyhexylthio)phenyl]-2-morpholinylpropane-1 -ketone, 2-methyl-1-[4-(2-propenyloxyethylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4- (2-Methylacryloxyethylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(3-propenyloxypropylthio) Phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(3-methylpropenyloxypropylthio)phenyl]-2-morpholinylpropane 1-ketone, 2-methyl-1-[4-(4-propenyloxybutylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[ 4-(4-Methylpropenyloxybutylthio)phenyl]-2-morpholinylpropan-1-one 2-methyl-1-[4-(2-acetamidoethyl)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(2-propane)醯Ethylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(2-butylindoleethylthio)phenyl]-2-morpholinyl Propane-1-one, 2-methyl-1-[4-(2-pentanylethylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4 -(2-hexylethylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(2-benzylideneethylthio)phenyl] -2-morpholinylpropan-1-one, 2-methyl-1-[4-(4-ethenylbutylthio)phenyl]-2-morpholinylpropan-1-one, and the like.

Among these compounds (1), 2-methyl-1-[4-(ethylthio)phenyl]-2-morpholinylpropan-1-one and 2-methyl-1-[ 4-(n-propylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(n-butylthio)phenyl]-2-morpholinyl Propane-1-one, 2-methyl-1-[4-(2-hydroxyethylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4- (3-hydroxypropylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl-1-[4-(3-hydroxybutylthio)phenyl]-2-? Lolinylpropan-1-one, 2-methyl-1-[4-(2-methylpropenyloxyethylthio)phenyl]-2-morpholinylpropan-1-one, 2-methyl Alkyl-1-[4-(4-ethinylbutylthio)phenyl]-2-morpholinylpropan-1-one or the like.

The compound (1) is excellent in solubility in a solvent, does not generate foreign matter such as undissolved matter or precipitate, and does not cause contamination of the baking furnace and the photomask by sublimation, and does not impair the transparency of the protective film. It is possible to form a component of an excellent spacer without pattern deletion and defect.

In the present invention, the compound (1) may be used singly or in combination of two or more kinds.

In the photosensitive resin composition of the present invention, the compound (1) is used in an amount of preferably 5 to 50 parts by weight, more preferably 5 to 30 parts by weight, per 100 parts by weight of the [A] copolymer. In this case, when the amount of the compound (1) is less than 5 parts by weight, the film remaining ratio tends to be small. On the other hand, if it exceeds 50 parts by weight, the solubility of the unexposed portion to the alkaline developing solution occurs. Smaller tendency.

Further, in the photosensitive resin composition of the present invention, at least one other photopolymerization initiator may be used in combination with the compound (1).

Examples of the other photopolymerization initiators include O-indenyl quinoid compounds, diimidazole compounds, benzoin compounds, acetophenones, benzophenones, and α-diketones. A compound, an onium salt as a radiation-sensitive cationic polymerization initiator, a metallocene compound, or the like. Among them, acetophenone-based compounds and diimidazole-based compounds and radiation-sensitive cationic polymerization initiators are preferred.

The above O-indenyl quinoid compound is a component having an effect of further improving sensitivity.

Specific examples of the O-indenyl quinoid type compound include 1-[9-ethyl-6-benzoguanidino-9.H.-oxazol-3-yl]-nonane-1,2-anthracene. alk-2-indole-O-benzoate, 1-[9-ethyl-6-benzylidenyl-9.H.-oxazol-3-yl]-nonane-1,2-decane -2-indole-O-acetate, 1-[9-ethyl-6-benzylidenyl-9.H.-carbazol-3-yl]-pentane-1,2-pentane-2 -肟-O-acetate, 1-[9-ethyl-6-benzylidenyl-9.H.-oxazol-3-yl]-octane-1-one oxime-O-acetate , 1-[9-ethyl-6-(2-methylbenzhydryl)-9.H.-oxazol-3-yl]-ethane-1-one oxime-O-benzoate, 1-[9-ethyl-6-(2-methylbenzhydryl)-9.H.-oxazol-3-yl]-ethane-1-one oxime-O-acetate, 1- [9-Ethyl-6-(1,3,5-trimethylbenzylidene)-9.H.-carbazol-3-yl]-ethane-1-one oxime-O-benzoic acid Ester, 1-[9-butyl-6-(2-ethylbenzylidenyl)-9.H.-oxazol-3-yl]-ethane-1-one oxime-O-benzoate 1,2-octanedione-1 [4-(phenylthio)phenyl]-2-(O-benzylidene fluorenyl), 1,2-butanedione-1-[4-(phenylthio)phenyl]-2-(O -benzimidoxime), 1,2-butanedione-1-[4-(phenylthio)phenyl]-2-(O-ethylindenyl), 1,2-octanedione-1 -[4-(methylthio)phenyl]-2-(O-benzylidene fluorenyl), 1,2-octanedione-1-[4-(phenylthio)phenyl]-2-( O-(4-methylbenzhydrylhydrazine)) and the like.

Of these O-indenyl oximes, 1-[9-ethyl-6-(2-methylbenzimidyl)-9.H.-oxazol-3-yl]-ethane- is particularly preferred. 1-ketooxime-O-acetate, 1,2-octanedione-1-[4-(phenylthio)phenyl]-2-(O-benzoguanidinopurine).

In the present invention, the O-indenyl quinoid type compounds may be used singly or in combination of two or more kinds.

In the photosensitive resin composition of the present invention, the total amount of the O-indenyl quinoid compound is preferably from 1 to 30 parts by weight, more preferably 2, based on 100 parts by weight of the polymerizable compound [B]. ~20 parts by weight. In this case, when the amount of the O-indenyl quinoid compound is less than 1 part by weight, there is a tendency that the residual film ratio is low at the time of development, and on the other hand, if it exceeds 30 parts by weight, the unexposed portion at the time of development appears to be a base. The solubility of the sexual imaging liquid tends to be small.

Examples of the acetophenone-based compound include an α-hydroxyketone compound, an α-aminoketone compound, and other compounds.

These acetophenone compounds may be used alone or in combination of two or more.

In the present invention, the sensitivity, the shape of the obtained spacer, the compressive strength, and the like can be further improved by using an acetophenone-based compound as another polymerization initiator.

Specific examples of the above-mentioned diimidazole compound include, for example, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbylphenyl)- 1,2'-diimidazole, 2,2'-bis(2-bromophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)-1,2'-diimidazole , 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-diimidazole, 2,2'-bis(2,4-dichloro Phenyl)-4,4',5,5'-tetraphenyl-1,2'-diimidazole, 2,2'-bis(2,4,6-trichlorophenyl)-4,4', 5,5'-tetraphenyl-1,2'-diimidazole, 2,2'-bis(2-bromophenyl)-4,4',5,5'-tetraphenyl-1,2'- Diimidazole, 2,2'-bis(2,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-diimidazole, 2,2'-di(2) , 4,6-tribromophenyl)-4,4',5,5'-tetraphenyl-1,2'-diimidazole, and the like.

Among the above diimidazole compounds, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-diimidazole, 2,2' is preferred. -bis(2,4-dichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-diimidazole, 2,2'-bis(2,4,6-trichloro Phenyl)-4,4',5,5'-tetraphenyl-1,2'-diimidazole, etc., particularly preferably 2,2'-bis(2,4-dichlorophenyl)-4, 4',5,5'-tetraphenyl-1,2'-diimidazole.

These diimidazole compounds may be used singly or in combination of two or more kinds.

By using these diimidazole compounds, sensitivity, resolution, and adhesion can be further improved.

Further, when a diimidazole compound is used as the other polymerization initiation, an aromatic compound having a dialkylamino group (hereinafter referred to as "a disensyl group containing a dialkylamino group") may be used in combination for sensitization.

Examples of the sensitizer containing a dialkylamino group include 4,4' bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, and p-dimethylaminobenzoic acid. Ethyl ester, ethyl p-diethylaminobenzoate, isoamyl p-dimethylaminobenzoate, isoamyl p-diethylaminobenzoate, and the like.

Among these sensitizers containing a dialkylamino group, 4,4'-bis(diethylamino)benzophenone is preferred.

The above-mentioned dialkylamino group-containing sensitizers may be used singly or in combination of two or more kinds.

The amount of the sensitizer containing a dialkylamino group is preferably 0.1 to 50 parts by weight, more preferably 1 to 20 parts by weight, per 100 parts by weight of the copolymer [A]. In this case, when the amount of the sensitizer containing a dialkylamino group is less than 0.1 part by weight, the resulting spacer film may be damaged or the pattern shape may be damaged. On the other hand, if it exceeds 50 parts by weight, the spacer may be present. The shape of the pattern is damaged.

Further, when a diimidazole compound and a dialkylamino group-containing sensitizer are used in combination as another polymerization initiator, a thiol compound may be added as a hydrogen donor compound. The diimidazole compound is sensitized by a sensitizer containing a dialkylamino group to cleave, thereby producing an imidazole radical. In this case, high polymerization initiation energy is not necessarily produced, and in many cases, the resulting spacer has an inverted cone shape. Not ideal shape. This problem can be alleviated by adding a thiol compound to a system in which a diimidazole compound and a dialkylamino group-containing sensitizer coexist. In other words, by supplying a hydrogen radical to a imidazole radical from a thiol compound, the imidazole radical becomes a neutral imidazole, and a component having a sulfur radical having a high polymerization initiation energy is produced, and as a result, the spacer shape is made more A preferred forward taper is preferred.

Examples of the above thiol compound include 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 2-mercaptobenzimidazole, 2-mercapto-5-methoxybenzothiazole, and 2-mercapto-5. An aromatic mercaptan such as methoxybenzimidazole; an aliphatic monothiol such as 3-mercaptopropionic acid, methyl 3-mercaptopropionate, ethyl 3-mercaptopropionate or octyl 3-mercaptopropionate. Examples of the difunctional or higher aliphatic thiol include 3,6-dioxa-1,8-octanedithiol, pentaerythritol tetrakis(mercaptoacetate), and pentaerythritol tetrakis(3-mercaptopropionate).

These thiol compounds may be used singly or in combination of two or more kinds.

The use ratio of the thiol compound is preferably 0.1 to 50 parts by weight, more preferably 1 to 20 parts by weight, per 100 parts by weight of the copolymer [A]. In this case, when the amount of the thiol compound used is less than 0.1 part by weight, the resulting spacer film may be defective or the pattern shape may be poor. On the other hand, if it exceeds 50 parts by weight, the shape of the spacer pattern may be impaired. .

Further, as the radiation-sensitive cationic polymerization initiator, examples of the onium salt include phenyldiazonium tetrafluoroborate, phenyldiazonium hexafluorophosphonate, phenyldiazonium hexafluoroarsenate, and phenyl group. Diazoindole trifluoromethanesulfonate, phenyldiazonium trifluoroacetate, phenyldiazonium p-toluenesulfonate, 4-methoxyphenyldiazonium tetrafluoroborate, 4-methoxy Phenyl diazonium hexafluorophosphonate, 4-methoxyphenyldiazonium hexafluoroarsenate, 4-methoxyphenyldiazonium trifluoromethanesulfonate, 4-methoxy Phenyldiazonium trifluoroacetate, 4-methoxyphenyldiazonium p-toluenesulfonate, 4-tert-butylphenyldiazonium tetrafluoroborate, 4-tert-butylphenyldiazo Hexafluorophosphonate, 4-tert-butylphenyldiazonium hexafluoroarsenate, 4-tert-butylphenyldiazonium trifluoromethanesulfonate, 4-tert-butylphenyldiazonium a diazonium salt such as trifluoroacetate or 4-tert-butylphenyldiazonium p-toluenesulfonate; triphenylsulfonium tetrafluoroborate, triphenylsulfonium hexafluorophosphonate, triphenylsulfonium Hexafluoroarsenate, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium Fluoroacetate, triphenylsulfonium p-toluenesulfonate, 4-methoxyphenyldiphenylphosphonium tetrafluoroborate, 4-methoxyphenyldiphenylphosphonium hexafluorophosphonate, 4-methoxybenzene Diphenylphosphonium hexafluoroarsenate, 4-methoxyphenyldiphenylphosphonium trifluoromethanesulfonate, 4-methoxyphenyldiphenylphosphonium trifluoroacetate, 4-methoxyphenyl Phenylhydrazine p-toluenesulfonate, 4-phenylthiophenyldiphenylphosphonium tetrafluoroborate, 4-phenylthiophenyldiphenylphosphonium hexafluorophosphonate, 4-phenylthiophenyl Phenylphosphonium hexafluoroarsenate, 4-phenylthiophenyldiphenylphosphonium trifluoromethanesulfonate, 4-phenylthiophenyldiphenylphosphonium trifluoroacetate, 4-phenylthiophenyl An anthracene salt such as diphenylphosphonium p-toluenesulfonate.

Further, examples of the metallocene compound include (1-6-η-cumene) (η-cyclopentadienyl) iron (1+) hexafluorophosphoric acid (1-).

As a commercially available product of these radiation-sensitive cationic polymerization initiators, for example, diazonium salt ATEKARUTOUSETOPP-33 (made by Asahi Kasei Kogyo Co., Ltd.), sulfur salt OPTOMERSP-150, OPTOMERSP-170 (Sui Dianhua Chemical Co., Ltd.) Manufactured by the company, and an aromatic ring-olefin metal derivative compound IrgaCure261 (Ciba speCia1ty Ch _{e m} i _{c a} l).

These photopolymerization initiators may be used singly or in combination of two or more kinds.

In the photosensitive resin composition of the present invention, the use ratio of the other photopolymerization initiator is preferably 100 parts by weight or less, more preferably 80 parts by weight based on 100 parts by weight of all the photopolymerization initiators. Hereinafter, it is particularly preferably 60 parts by weight or less. At this time, if the use ratio of the other photopolymerization initiator exceeds 100 parts by weight, it is possible to impair the effects expected by the present invention.

-additive-

The photosensitive resin composition of the present invention may further contain an additive other than the above components, as long as it does not impair the effects expected by the present invention.

For example, in order to improve coatability, an interface active agent may be blended. As the surfactant, a fluorine-based surfactant and a siloxane-based surfactant can be used.

As the fluorine-based surfactant, a compound having a fluoroalkyl group or a fluoroalkylene group in at least one of a terminal, a main chain and a side chain can be used. Specific examples thereof include 1,1,2,2-tetrafluorooctyl (1,1,2,2-tetrafluoropropyl)ether and 1,1,2,2-tetrafluorooctylhexyl ether. Octaethylene glycol di(1,1,2,2-tetrafluorobutyl)ether, hexaethylene glycol (1,1,2,2,3,3-hexafluoropentyl)ether, octapropylene glycol di(1) , 1,2,2-tetrafluorobutyl)ether, hexapropylene glycol bis(1,1,2,2,3,3-hexafluoropentyl)ether, sodium perfluorododecylsulfonate, 1,1 , 2,2,8,8,9,9,10,10-decafluoro-n-dodecane, 1,1,2,2,3,3,-hexafluorodecane, sodium fluoroalkylbenzene sulfonate , sodium fluoroalkyl sulfonate, sodium fluoroalkyl carboxylate, fluoroalkyl polyoxyethylene ether, diglycerol tetra (fluoroalkyl polyoxyethylene ether), fluoroalkyl ammonium iodide, fluorinated Alkyl betaines, fluoroalkyl polyoxyethylene ethers, perfluoroalkyl polyoxyethylenes, perfluoroalkyl alkoxides, fluoroalkyl esters, and the like.

Further, as their commercial products, for example, BM-1000, BM-1100 (above BM CHEMIE), MEGA FAKKUF142D, MEGA FAKKUF172, MEGA FAKKUF173, MEGA FAKKUF183, MEGA FAKKUF178, MEGA FAKKUF191, MEGA FAKKUF471, MEGA FAKKUF476 (all manufactured by Dainippon Ink Chemical Industry Co., Ltd.), PROLITEF C 170C, FC-171, FC-430, FC-431 (above, manufactured by Sumitomo 3M Co., Ltd.), SAPRONS-112, SAPRONS- 113, SAPRONS-131, SAPRONS-141, SAPRONS-145, SAPRONS-382, SAPRONSC-101, SAPRONSC-102, SAPRONSC-103, SAPRONSC-104, SAPRONSC-105, SAPRONSC-106 (above, manufactured by Asahi Glass Co., Ltd.) ), EPPENDOF EF 301, EPPENDOF EF 303, EPPENDOF EF 352 (above, manufactured by New Akita Chemical Co., Ltd.), FUTAGENET FT-100, FUTAGENET FT-110, FUTAGENET FT-140A, FUTAGENET FT-150, FUTAGENET FT-250 , FUTAGENET FT-251, FUTAGENET FTX-251, FUTAGENET FTX-218, FUTAGENET FT-300, FUTAGENET FT-310, FUTAGENET FT-400S On, manufactured by NEOS Co., Ltd.).

Further, as the siloxane-based surfactant, for example, products sold under the following trade names: TORAYSILICON DC3PA, TORAYSILICON DC7PA, TORAYSILICON SH11PA, TORAYSILICON SH21PA, TORAYSILICON SH28PA, TORAYSILICON SH29PA, TORAYSILICON SH30PA, TORAYSILICON SH-190, TORAYSILICON SH-193, TORAYSILICON SZ-6032, TORAYSILICON SF-8428, TORAYSILICON DC-57, TORAYSILICON DC-190 (above, manufactured by Toray DAWACONIGU Co., Ltd.), TSF-4440, TSF-4300, TSF-4445, TSF -4446, TSF-4460, TSF-4452 (above manufactured by GE Toshiba Corporation).

Further, examples of the surfactant other than the above include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; and polyoxyethylene. Polyoxyethylene aryl ether such as n-octyl phenyl ether or polyoxyethylene n-decyl phenyl ether; polyoxyethylene dialkyl ester such as polyoxyethylene dilaurate or polyoxyethylene distearate An ionic surface surfactant, and a commercially available product, KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), POLYFLOW-No. 57, 95 (manufactured by Kyoeisha Oil Chemical Industry Co., Ltd.), and the like can be cited.

These surfactants may be used singly or in combination of two or more kinds.

The amount of the surfactant to be added is preferably 5 parts by weight or less, more preferably 2 parts by weight or less based on 100 parts by weight of the copolymer [A]. In this case, when the amount of the surfactant is more than 5 parts by weight, film cracking tends to occur at the time of coating.

Further, in order to further improve the adhesion to the substrate, an adhesion aid may be blended.

The above-mentioned adhesion aid is preferably a functional decane coupling agent, and examples thereof include a decane coupling agent having a reactive functional group such as a carboxyl group, a methacryl fluorenyl group, an isocyanate group or an epoxy group. More specifically, it may, for example, be trimethoxymethane alkyl benzoic acid, γ-methyl propylene methoxy propyl trimethoxy decane, vinyl triethoxy decane, vinyl trimethoxy decane, γ-isocyanate Propyltriethoxydecane, γ-glycidoxypropyltrimethoxydecane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane, and the like.

These adhesion aids may be used alone or in combination of two or more.

The compounding amount of the adhesion aid is preferably 20 parts by weight or less, more preferably 10 parts by weight or less based on 100 parts by weight of the copolymer [A]. At this time, if the compounding amount of the adhesion aid exceeds 20 parts by weight, there is a tendency that development residue tends to occur.

In the photosensitive resin composition of the present invention, other additives may be added for the purpose of improving storage stability and the like. Specific examples thereof include sulfur, benzoquinones, hydroquinones, polyoxygen compounds, amines, and nitronitroso compounds. Examples thereof include 4-methoxyphenol, N-nitroso-N-phenylhydroxylamine aluminum, and the like. It is preferably used in an amount of 3.0 parts by weight or less, more preferably 0.001 to 0.5 parts by weight, per 100 parts by weight of the copolymer [A]. When it exceeds 3.0 parts by weight, sufficient sensitivity cannot be obtained and the pattern shape is deteriorated.

Further, in the photosensitive resin composition of the present invention, in order to improve heat resistance, an N-(alkoxymethyl)glycoluride compound, an N-(alkoxymethyl)melamine compound, and a double molecule may be added in one molecule. A compound having an epoxy group or more.

Specific examples of the above N-(alkoxymethyl)glycolide compound include N,N,N,N-tetrakis(methoxymethyl)glycoluril, N,N,N,N-tetra (B Oxymethyl)glycoluril, N,N,N,N-tetrakis(n-propoxymethyl)glycoluril, N,N,N,N-tetrakis(isopropoxymethyl)glycolil, N, N,N,N-tetrakis(n-butoxymethyl)glycoluril, N,N,N,N-tetrakis(tert-butoxymethyl)glycoluril and the like. Of these, N, N, N, N-tetrakis(methoxymethyl) glycoluril is particularly preferred.

Further, specific examples of the above N-(alkoxymethyl)melamine compound include N,N,N,N,N,N-hexa(methoxymethyl)melamine, N,N,N,N. ,N,N-hexa(ethoxymethyl)melamine, N,N,N,N,N,N-hexa(n-propoxymethyl)melamine, N,N,N,N,N,N- Hexa(isopropoxymethyl)melamine, N,N,N,N,N,N-hexa(n-butoxymethyl)melamine, N,N,N,N,N,N-hexa Oxymethyl group) melamine or the like. Of these, N,N,N,N,N,N-hexa(methoxymethyl)melamine is particularly preferred. As their commercial products, NIKALAC N-2702, MW-30M (above, manufactured by Sanwa Chemical Co., Ltd.) and the like can be cited.

Further, examples of the compound having a bifunctional or higher epoxy group in one molecule include ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, and the like. Propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, trimethylolpropane triglycidyl Ether, hydrogenated bisphenol A diglycidyl ether, bisphenol A diglycidyl ether, and the like. Specific examples of their commercial products include EPOLIGHT 40E, EPOLIGHT 100E, EPOLIGHT 200E, EPOLIGHT 70P, EPOLIGHT 200P, EPOLIGHT 400P, EPOLIGHT 40E, EPOLIGHT 1500NP, EPOLIGHT 1600, EPOLIGHT 80MF, EPOLIGHT 100MF, EPOLIGHT 4000, EPOLIGHT 3002. (above, manufactured by Kyoeisha Oil Chemical Industry Co., Ltd.). They may be used alone or in combination of two or more.

Composition solution

When the photosensitive resin composition of the present invention is used, the constituent components such as the copolymer [A], the polymerizable compound [B], and the photopolymerization initiator [C] are usually dissolved in a suitable solvent to prepare a composition. Solution.

As a solvent used for preparation of the composition solution, a solvent which can uniformly dissolve each component constituting the photosensitive resin composition and does not react with each component is used.

As such a solvent, the same solvent as the solvent exemplified as the solvent which can be used for the manufacture of the above-mentioned copolymer [A] can be mentioned.

In such a solvent, it is preferred to use, for example, an alcohol, a glycol ether, or an ethylene glycol alkyl ether acetate from the viewpoints of solubility of each component, reactivity with each component, easiness of formation of a coating film, and the like. Esters, esters and diethylene glycol. Among them, it is particularly preferable to use, for example, benzyl alcohol, 2-phenylethyl alcohol, 3-phenyl-1-propanol, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, and Glycol diethyl ether, diethylene glycol ethyl methyl ether, diglyme, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl methoxypropionate, ethoxy propionate ester.

Further, in order to increase the in-plane uniformity of the film thickness, a high boiling point solvent may be used in combination with the above solvent. Examples of the high-boiling solvent which can be used in combination include N-methylformamide, N,N-dimethylformamide, N-methylformamide, N-methylacetamide, and N. N-dimethylacetamide, N-methylpyrrolidone, dimethyl hydrazine, benzyl ethyl ether, dihexyl ether, acetonyl acetone, isophorone, hexanoic acid, octanoic acid, 1-octanol, 1-nonanol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, phenyl cellosolve acetate Wait. Among them, preferred are N-methylpyrrolidone, γ-butyrolactone, and N,N-dimethylacetamide.

The composition solution thus prepared may be filtered by a micropore screening method having a pore diameter of, for example, about 0.2 to 0.5 μm, if necessary, and then supplied.

The photosensitive resin composition of the present invention is particularly suitable as a material for forming a protective film for a liquid crystal display panel such as a liquid crystal panel or a touch panel, and a spacer.

Protective film for display panel and method for forming spacer for display panel

The method for forming a protective film or a spacer for a liquid crystal display panel of the present invention is characterized by comprising at least the following steps in the following order: (1) a step of forming a photosensitive resin composition coating film of the present invention on a substrate, (2) a step of exposing at least a portion of the coating film, (3) a step of developing the exposed coating film, and (4) a step of heating the coating film after development.

(1) A transparent conductive film is formed on one surface of a transparent substrate, and a photosensitive resin composition is applied onto the transparent conductive film, and then the coated surface is heated (preheated) to form a coating film.

Examples of the transparent substrate used for the formation of the spacer include a glass substrate, a resin substrate, and the like. More specifically, a glass substrate such as soda lime glass or alkali-free glass; a plastic resin such as polyethylene terephthalate, polybutylene terephthalate, polyether oxime, polycarbonate, or polyimine; Substrate.

As the transparent conductive film provided on one surface of the transparent substrate, a NESA film made of tin oxide (SnO ₂ ) (registered trademark of PPG, USA), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ), or the like can be used. .

Further, the preheating conditions vary depending on the type and blending ratio of each component, and usually, it can be carried out at 70 to 120 ° C for about 1 to 15 minutes.

The method of forming a protective film for a liquid crystal display panel and a spacer using the photosensitive resin composition of the present invention on a substrate such as a transparent substrate or a resin substrate can be carried out, for example, by (1) coating method or (2) ruthenium film method. .

As a coating method of the composition solution, for example, a suitable method such as a spray coating method, a roll coating method, a spin coating method (spin coating method), a slit die coating method, a bar coating method, or an inkjet coating method can be employed. It is preferred to use a spin coating method or a slit die coating method.

Further, in forming the coating film of the photosensitive resin composition of the present invention, when the (2) ruthenium film method is employed, the ruthenium film method is on the base film, preferably on the plastic base film. A method of forming a photosensitive layer of a photosensitive resin composition (hereinafter referred to as "photosensitive dry film").

The photosensitive dry film can be formed by applying the photosensitive resin composition of the present invention to a liquid film on a base film, drying it, and laminating the photosensitive layer. As the base film of the photosensitive dry film, for example, a synthetic resin film such as polyethylene terephthalate (PET), polyethylene, polypropylene, polycarbonate, or polyvinyl chloride can be used. The thickness of the base film is preferably in the range of 15 to 125 μm. The thickness of the obtained photosensitive layer is preferably from 1 to 30 μm.

Further, when the photosensitive dry film is not used, the coating layer may be further laminated on the photosensitive layer and stored. The coating film must have an appropriate mold release property, which does not peel off when not in use, and can be easily peeled off during use. As a coating film which satisfies such a condition, for example, a film in which a siloxane-based release agent is applied or sintered on the surface of a synthetic resin film such as a PET film, a polypropylene film, a polyethylene film or a polyvinyl chloride film can be used. It is sufficient that the thickness of the coating film is usually about 25 μm.

After forming the coating film of the photosensitive resin composition of the present invention on the substrate, it is preferred to carry out preheating. The preheating conditions differ depending on the type of the constituent components, the blending ratio, and the like, and are usually carried out at 70 to 90 ° C for about 1 to 15 minutes.

(2) Step Next, at least a part of the coating film is exposed to a preheated coating film (coating film) to be polymerized by, for example, a mask having a predetermined pattern.

As the radiation used for the exposure, visible light, ultraviolet light, far ultraviolet light, charged particle beam, X-ray or the like can be appropriately selected, and a radiation having a wavelength in the range of 190 to 450 nm is preferable.

The exposure amount is a value measured by an illuminometer (OAI model 356, manufactured by OAI Optical Associates Inc.) with an intensity of the exposure light having a wavelength of 365 nm, and is usually 100 to 10000 J/m ² , preferably 1,500 to 4,000 J/m ² .

(3) Step Next, the exposed coating film is developed by a developing liquid to remove unnecessary portions, and a pattern is formed.

As the developing method, for example, any one of a liquid-filling method, a dipping method, and a rinsing method, the development time is usually 30 to 180 seconds.

As the developing solution, for example, inorganic bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium citrate, sodium metasilicate, and ammonia; primary amines such as ethylamine and n-propylamine; diethylamine and a secondary amine such as n-propylamine; a tertiary amine such as trimethylamine, methyldiethylamine, ethyldimethylamine or triethylamine; a tertiary alkanol such as dimethylethanolamine, methyldiethanolamine or triethanolamine Amines; pyrrole, acridine, N-methyl acridine, N-methylpyrrolidine, 1,8-diazabicyclo[5.4.0]-7-undecene, 1,5-diaza Cycloaliphatic tertiary amines such as heterobicyclo[4.3.0]-5-pinene; aromatic tertiary amines such as pyridine, trimethylpyridine, lutidine, quinoline; tetramethylammonium hydroxide, hydrogen An aqueous solution of a basic compound such as a quaternary ammonium salt such as tetraethylammonium oxide.

Further, an appropriate amount of a water-soluble organic solvent such as methanol or ethanol and/or an interfacial surfactant may be added to the aqueous solution of the basic compound.

After the development, for example, washing is performed for 30 to 90 seconds by, for example, running water washing, and the unnecessary portion is removed, and then compressed air or compressed nitrogen is blown and dried to form a predetermined pattern.

(4) After the step development, the pattern (coating film) is heated by a heating device such as a hot plate or an oven at a predetermined temperature, for example, 150 to 250 ° C for a predetermined period of time, for example, for 5 to 30 minutes on a hot plate. The target protective film or spacer can be obtained by treating in an oven for, for example, 30 to 90 minutes.

Liquid display panel

The liquid crystal display panel of the present invention can be produced by the following method. First, two substrates in which the protective film having the liquid crystal alignment energy of the present invention is formed are formed so that the liquid crystal alignment directions of the respective protective films are perpendicular or antiparallel to each other, and the two substrates are opposed to each other through the gap (cell gap). In the spacer of the invention, the peripheral portions of the two substrates are bonded to each other, and liquid crystal cells are filled in the cell gap separated from the surface of the substrate and the spacer, and the filling port is closed to constitute a liquid crystal cell. Then, a polarizing plate is bonded to the outer surface of the liquid crystal cell, that is, the other side surface of each of the substrates constituting the liquid crystal cell, so that the polarization direction thereof is uniform or perpendicular to the alignment direction of the liquid crystal forming the protective film on the other surface of the liquid crystal cell. The liquid crystal display panel of the present invention is obtained.

Examples of the liquid crystal include a nematic liquid crystal and a disk-shaped liquid crystal. Among them, a nematic liquid crystal is preferable, and for example, a Schiff base liquid crystal, an oxidized azo liquid crystal, a biphenyl liquid crystal, or a phenyl ring can be used. Alkane liquid crystal, ester liquid crystal, terphenyl liquid crystal, biphenyl cyclohexane liquid crystal, pyrimidine liquid crystal, dioxane liquid crystal, bicyclooctane liquid crystal, cubic liquid crystal or the like. Further, in these liquid crystals, a cholesteric liquid crystal such as chlorinated cholesterol, cholesterol phthalate or cholesterol carbonate, and a chiral agent sold under the trade names "C-15" and "CB-15" (manufactured by MERCK) may be added. Wait for use. Further, a ferroelectric liquid crystal such as p-methoxybenzylidene-p-amino-2-methylbutylcinnamate may also be used.

In addition, as a polarizing plate to be used for the outer side of the liquid crystal cell, a polarizing plate called a H film which absorbs iodine while extending the orientation of the polyvinyl alcohol is sandwiched between the cellulose acetate protective film, or A polarizing plate or the like obtained by the H film itself.

Example

Hereinafter, the present invention will be more specifically described by way of examples and comparative examples, but the invention is not limited to these examples.

Synthesis Example 1

In a flask equipped with a cooling tube and a stirrer, 7 parts by weight of 2,2'-azobis(2,4-dimethylvaleronitrile) and 200 parts by weight of propylene glycol monomethyl ether acetate were charged. Next, 5 parts by weight of styrene, 20 parts by weight of methacrylic acid, 25 parts by weight of tricyclo [5.2.1.0 ^{2 , 6} ]decane-8-yl methacrylate, and 25 parts by weight of 3-(methacryloxyl) were introduced. The methyl group)-3-ethyloxetane, 20 parts by weight of tetrahydrofurfuryl methacrylate, and 5 parts by weight of 1,3-butadiene were replaced with nitrogen, and then slowly stirred. The temperature of the solution was raised to 70 ° C, and the temperature was maintained for 5 hours to obtain a polymer solution containing the copolymer [A-1]. The obtained polymer solution had a solid content concentration of 30.0% by weight and a polymer having a weight average molecular weight of 18,000 (the weight average molecular weight was polystyrene measured by GPC (gel permeation spectroscopy) HLC-8020 (manufactured by Tosoh Corporation). Converted molecular weight).

Synthesis Example 2

In a flask equipped with a cooling tube and a stirrer, 7 parts by weight of 2,2'-azobis(2,4-dimethylvaleronitrile) and 200 parts by weight of diethylene glycol ethyl methyl ether were charged. Next, 5 parts by weight of styrene, 20 parts by weight of methacrylic acid, 25 parts by weight of tricyclo[5.2.1.0 ^{2 , 6} ]decane-8-yl methacrylate, 25 parts by weight of glycidyl methacrylate, and 25 parts by weight of styrene, 20 parts by weight of tetrahydrofurfuryl methacrylate and 5 parts by weight of 1,3-butadiene were replaced with nitrogen, and then slowly stirred. The temperature of the solution was raised to 70 ° C, and the temperature was maintained for 5 hours to obtain a polymer solution containing the copolymer [A-2]. The solid content concentration of the obtained polymer solution was 31.0% by weight, and the weight average molecular weight of the polymer was 20,000 (the weight average molecular weight was polystyrene measured by GPC (gel permeation spectroscopy) HLC-8020 (manufactured by Tosoh Corporation). Converted molecular weight).

Synthesis Example 3

In a flask equipped with a cooling tube and a stirrer, 5 parts by weight of 2,2'-azobisisobutyronitrile and 200 parts by weight of propylene glycol monomethyl ether acetate were charged. Successively, 10 parts by weight of styrene, 20 parts by weight of methacrylic acid, 30 parts by weight of methacrylic acid, tricyclo [5.2.1.0 ^{2. 6]} dec-8-yl methacrylate, 20 parts by weight of benzyl methacrylate, 20 The tetrahydrofurfuryl methacrylate was replaced by nitrogen and then slowly stirred. The temperature of the solution was raised to 90 ° C, and the temperature was maintained for 4 hours to obtain a polymer solution containing the copolymer [A-3]. The obtained polymer solution had a solid content concentration of 31.0% by weight and a polymer having a weight average molecular weight of 21,000 (the weight average molecular weight was polystyrene measured by GPC (gel permeation spectroscopy) HLC-8020 (manufactured by Tosoh Corporation). Converted molecular weight).

Example 1 Modulation of composition solution

100 parts by weight (solid content) as a solution of the copolymer [A-1] obtained in Synthesis Example 1 of the copolymer [A], and 80 parts by weight of KAYARAD DPHA (Nippon Chemical Co., Ltd.) as the polymerizable compound [B] 20 parts by weight of 2-methyl-1-[4-(n-butylthio)phenyl]-2-morpholinylpropan-1-one as photopolymerization initiator [C], 3 parts by weight 1,2-octanedione-1-[4-(phenylthio)phenyl]-2-(O-benzhydrylhydrazine) (CGI-124, manufactured by Ciba Specialty Chemicals, Specialty Chemicals Co., Ltd.) was dissolved in In the propylene glycol monomethyl ether acetate, the solid content concentration was 30% by weight, and then filtered with a micropore filter having a pore diameter of 0.2 μm to prepare a composition solution (S-1).

(I) Formation of Protective Film The composition solution was applied onto an alkali-free glass substrate using a spin coater, and then preheated on a hot plate at 90 ° C for 3 minutes to form a coating film having a film thickness of 1.5 μm.

The obtained coating film was exposed to ultraviolet light having an exposure intensity of 200 W/m ² at a wavelength of 365 nm at an exposure interval of 150 μm without using a mask. Subsequently, after developing for 60 seconds at 25 ° C with a 0.05% by weight aqueous potassium hydroxide solution, it was rinsed with pure water for 1 minute. Then, it was heated in an oven at 220 ° C for 60 minutes to form a protective film.

(II) Formation of a spacer The above composition solution was applied onto an alkali-free glass substrate using a spin coater, and then preheated on a hot plate at 90 ° C for 3 minutes to form a coating film having a film thickness of 4.0 μm.

The obtained coating film was exposed by an ultraviolet ray having an exposure intensity of 300 W/m ² at a wavelength of 365 nm at an exposure interval of 150 μm by a mask having a 10 μm square pattern remaining. Subsequently, after developing for 60 seconds at 25 ° C with a 0.05% by weight aqueous potassium hydroxide solution, it was rinsed with pure water for 1 minute. Then, it was heated in an oven at 220 ° C for 60 minutes to form a spacer.

(III) Evaluation of Transparency A transmittance of 400 to 800 nm of the protective film was measured using a spectrophotometer (150-20 type double beam (manufactured by Hitachi, Ltd.)). At this time, the case where the minimum transmittance exceeds 97% is represented by ○, the case of 90 to 97% is represented by Δ, and the case of less than 90% is represented by ×.

(IV) Evaluation of the degree of resolution In addition to changing the exposure amount, the spacer is formed in the same manner as in the formation of the spacer (II) described above, and is distinguished by an exposure amount of 90% or more after the development. The minimum pattern size was evaluated.

(V) Evaluation of cross-sectional shape of the pattern The cross-sectional shape of the pattern obtained in the above (II) was observed using a scanning electron microscope, and as a result, the shape was expressed in accordance with any one of A to C shown in Fig. 1 . When the pattern side as shown in A is a forward taper, the pattern shape can be said to be good. When the pattern side is formed vertically as shown by B, the pattern shape can be said to be acceptable. Further, as shown in C, when a reverse tapered shape (in the cross-sectional shape, the side of the film surface is longer than the side of the substrate side, which is an inverted triangular shape) is formed, the pattern is peeled off at the subsequent polishing step. The possibility is very large, so this shape is rated bad.

(VI) Evaluation of Adhesiveness In the same manner as in the above (I), a cured film for evaluation of adhesion was formed, and an adhesion test was performed. The test method was carried out in accordance with the mesh belt method of 8.5.2 in the adhesion test of JIS K-5400 (1900) 8.5.

(VII) Evaluation of heat resistance In the above (I), the protective film formed at a preheating temperature of 90 ° C was heated in an oven at 250 ° C for 60 minutes. The rate of change in film thickness at this time was measured. When the rate of change is within 5% before and after heating, it can be said that the heat resistance stability is good, and when it exceeds 5%, the heat resistance dimensional stability is called a defect.

(VIII) Evaluation of sublimation property The above composition solution was applied onto a substrate and dried to form a coating film having a film thickness of 6.0 μm. Then, using the standard substance n-octane (specific gravity = 0.701, injection amount: 0.02 μl), the coating film was subjected to air phase chromatography/mass analysis at 100 ° C / 10 min purge conditions. Empty sampler: manufactured by Nippon Analytical Industries Co., Ltd., JHS-100A, gas chromatography/mass spectrometer: JEOL JMS-AX505W type mass spectrometer), the peak value A derived from the photopolymerization initiator was determined, and Calculate the formula and calculate the amount of volatilization in terms of n-octane. The greater the amount of volatilization, the greater the sublimation.

Calculation formula of volatilization amount in n-octane conversion Volatile amount (μg) = A × (amount of n-octane) (μ g) / (peak area of n-octane)

(IX) Evaluation of compression characteristics Using a micro compression tester (trade name FISCHER SCOPE H100C, manufactured by FISCHER INSTRUMENTS), a plane indenter having a diameter of 50 μm was used, and both the bearing speed and the unloading speed were 2.6 mN/sec until the load was carried. The load of 50 mN is maintained for 5 seconds, the load is removed, and the load-weight-deformation curve at the time of load and the load-weight-deformation curve at the time of unloading are prepared. At this time, as shown in Fig. 2, the difference between the amount of deformation of the load of 50 mN and the amount of deformation of the load of 5 mN is L1, and the difference between the amount of deformation of the load of 50 mN at the time of unloading and the amount of deformation of the load of 5 mN is L2, and the following formula is used. Calculate the elastic recovery rate.

Elastic recovery rate (%) = L2 × 100 / L1

Examples 2 to 6, Comparative Examples 1 to 4

In the first embodiment, the composition solution [S-2 to S- was prepared in the same manner as in Example 1 except that the components and the amounts of the components [A] to [C] shown in Table 1 were used. 6, s-1~s-4], spacers were formed and evaluated. The addition amount of [B] to [C] is a weight ratio with respect to 100 parts by weight of the copolymer [A].

The evaluation results are shown in Table 2.

In Table 1, the abbreviation of the component means the following compound.

(B-1): KAYARAD DPHA (manufactured by Nippon Kayaku Co., Ltd.) (C-1): 2-methyl-1-[4-(n-butylthio)phenyl]-2-morpholinylpropane 1-ketone (C-2): 2-methyl-1-[4-(2-hydroxyethylthio)phenyl]-2-morpholinylpropan-1-one (C-3): 1 2-octanedione-1-[4-(phenylthio)phenyl]-2-(O-benzylidenehydrazine) (manufactured by Ciba Specialty Chemical Co., Ltd., CGI-124) (C-4): 2 -Methyl-1-[4-(methylthio)phenyl]-2-morpholinylpropan-1-one (IRUGAKUA 907, manufactured by Ciba Specialty Chemical Co., Ltd.) (C-5): 2, 2'- (2-Chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-diimidazole (C-6): 4,4'-bis(diethylamino)benzophenone ( C-7): 2-mercaptobenzothiazole

Fig. 1 is a view illustrating a cross-sectional shape of a pattern.

Fig. 2 is a view exemplifying a load-deformation amount curve at the time of load and at the time of unloading in the elastic recovery rate evaluation.

Claims (14)

A photosensitive resin composition characterized by comprising a copolymer of [A] (a1) an ethylenically unsaturated carboxylic acid and (a2) another ethylenically unsaturated compound (except for an ethylenically unsaturated carboxylic anhydride), [B a polymerizable compound having an ethylenically unsaturated bond, and [C] a photopolymerization initiator comprising a compound represented by the following formula (1); In the formula (1), n is an integer of 2 to 12, and R ₁ represents hydrogen, a hydroxyl group, or any group having a structure represented by each of the following (I), (II) or (III), in (III) R ₂ is an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, or an alkyl group having 1 to 6 carbon atoms and 1 carbon atom. ~6 alkoxy substituted phenyl, The photosensitive resin composition of claim 1, wherein the (a1) ethylenically unsaturated carboxylic acid is selected from the group consisting of acrylic acid, methacrylic acid, crotonic acid, 2-methylpropenyloxyethyl succinate, At least one of a group consisting of 2-methylpropenyloxyethyl hexahydrophthalate, maleic acid, fumaric acid, citraconic acid, mesaconic acid, and itaconic acid, (a2) other The ethylenically unsaturated compound is selected from the group consisting of 2-methylcyclohexyl acrylate, hydroxyethyl methacrylate, trimethyl methacrylate [5.2.1.0 ^2,6 ]decane-8-yl ester, styrene, A Glycidyl acrylate, 3-(methacryloxymethyl)-3-ethyloxetane, tetrahydrofurfuryl methacrylate, 1,3-butadiene, phenyl horse At least one of the group consisting of imine and cyclohexylmaleimide. The photosensitive resin composition of claim 1, wherein in the copolymer [A], the content ratio of the repeating unit derived from (a1) is 5 to 50% by weight, derived from the repeating unit of (a2) The content ratio is 95 to 50% by weight. The photosensitive resin composition of the first aspect of the invention, wherein the polymerizable compound [B] is a monofunctional, difunctional or trifunctional or higher (meth) acrylate. The photosensitive resin composition of the first aspect of the invention, wherein the polymerizable compound [B] is used in an amount of 50 to 200 parts by weight based on 100 parts by weight of the copolymer [A]. The photosensitive resin composition of the first aspect of the invention, wherein the photopolymerization initiator [C] is used in an amount of 5 to 50 parts by weight based on 100 parts by weight of the copolymer [A]. The photosensitive resin composition of the first aspect of the invention, which comprises, in addition to the photopolymerization initiator [C], 60 parts by weight or less based on 100 parts by weight of all the photopolymerization initiators, and is selected from the group consisting of O - Ray-sensitive compounds, diimidazoles, benzoin compounds, acetophenones, benzophenones or alpha-diketones, or strontium salts or metallocene compounds At least one of the other photopolymerization initiators of the cationic polymerization initiator. The photosensitive resin composition according to any one of claims 1 to 7, It is used to form a protective film for a liquid crystal display panel or to form a spacer. A protective film for a liquid crystal display panel, which is formed by the photosensitive resin composition of claim 8 of the patent application. A spacer for a liquid crystal display panel formed of the photosensitive resin composition of claim 8 of the patent application. A method for forming a protective film for a liquid crystal display panel, characterized by comprising at least the following steps in the order described below, (1) forming a coating film of the photosensitive resin composition of claim 8 on the substrate And (2) a step of exposing at least a portion of the coating film, (3) a step of developing the exposed coating film, and (4) heating the coating film after development The steps. A method for forming a spacer for a liquid crystal display panel, characterized by comprising at least the following steps in the order described below, (1) forming a coating film of the photosensitive resin composition of claim 8 on the substrate And (2) a step of exposing at least a portion of the coating film, (3) a step of developing the exposed coating film, and (4) heating the coating film after development The steps. A liquid crystal display panel having a protective film for a liquid crystal display panel according to claim 9 of the patent application. A liquid crystal display panel having a spacer for a liquid crystal display panel according to claim 10 of the patent application.