KR20050076753A - Radiation sensitive resin composition for forming spacer, spacer and its forming method, and liquid crystal display device - Google Patents

Abstract

The present invention provides a high resolution, high sensitivity, easy to use spacers excellent in various performances such as pattern shape, compressive strength, rubbing resistance, and adhesion to a transparent substrate, even under exposure to radiation that does not substantially include a wavelength of less than 350 nm. Provided is a radiation-sensitive resin composition for a spacer that can be formed.

In the present invention, the radiation-sensitive resin composition for spacers

[A] A copolymer of (a1) unsaturated carboxylic acid and / or unsaturated carboxylic anhydride with (a2) epoxy group-containing unsaturated compound and (a3) other unsaturated compound,

[B] a polymerizable unsaturated compound,

[C] a biimidazole compound,

[D] a radiation sensitive polymerization initiator having a carbonyl group, and

[E] A compound having a dialkylamino group and / or a [F] thiol compound.

Description

Radiation Sensitive Resin Composition for Forming Spacer, Spacer and Its Forming Method, and Liquid Crystal Display Device

The present invention relates to a radiation-sensitive resin composition for forming a spacer, a spacer, a method for forming the same, and a liquid crystal display device, and more particularly, a spacer can be formed even under exposure by radiation that does not substantially include a wavelength of less than 350 nm. The radiation sensitive resin composition for spacer formation, the spacer formed therefrom, its formation method, and the liquid crystal display element which has this spacer.

In the liquid crystal display element, spacer particles such as glass beads and plastic beads having a predetermined particle diameter are conventionally used to maintain a constant gap between two transparent substrates, but these spacer particles are irregularly formed on a transparent substrate such as a glass substrate. Because of the dispersion, the presence of the spacer particles in the pixel formation region causes a phenomenon in which the spacer particles are imprinted, or incident light is scattered and the contrast of the liquid crystal display element is lowered.

In order to solve these problems, a method of forming spacers by photolithography has been adopted. In this method, the radiation-sensitive resin composition is applied onto a substrate, and the ultraviolet ray is exposed through a predetermined mask and then developed to form a dot or stripe spacer, and the spacer is formed only at a predetermined place other than the pixel formation region. As such, the problem as described above is basically solved.

 By the way, the radiation from a mercury lamp used as a light source in port lithography is usually around 436 nm (g line), near 404 nm (h line), around 365 nm (i line), near 335 nm, near 315 nm (j Line), near to 303 nm, and the like, and exhibit a strong intensity, so that the radiation-sensitive polymerization initiator which is a constituent of the radiation-sensitive resin composition is selected to have a maximum absorption wavelength in the wavelength region of the strong spectrum. In most cases, a radiation sensitive polymerization initiator having a maximum absorption wavelength is used in a region of i-line or less from the viewpoint of transparency (see Japanese Patent Laid-Open No. 2001-261761, for example). When a radiation sensitive polymerization initiator having a maximum absorption wavelength in the vicinity of g- and h-rays whose wavelength is longer than i-rays is used, since the radiation-sensitive polymerization initiator has absorption in a wavelength region close to visible light, Transparency of the film formed by coloring a resin composition falls. When the transparency of the film is low, the curing reaction proceeds on the surface of the film during exposure, and the curing reaction in the depth direction of the film is insufficient. As a result, the shape of the spacer obtained after development is reverse tapered (cross-sectional substrate as a cross-sectional shape). An inverted triangle longer than the side of the side), which causes the spacer to peel off during the subsequent rubbing treatment of the alignment film.

On the other hand, when the spacer is formed by photolithography on a transparent substrate used in an actual spacer forming process, for example, a color filter, etc., a proximity exposure machine is often used, but recently, in order to improve the throughput of the proximity exposure machine, In general, high intensity mercury lamps are used. In this case, although it is effective to improve the throughput, since it lowers the life of the mirror (reflecting mirror) used in the exposure machine, it is often used to block short wavelength radiation of less than 350 nm having a high energy with a filter. However, since most of the conventional radiation-sensitive polymerization initiators have a maximum absorption wavelength at less than 350 nm, blocking radiation below the wavelength of 350 nm can sufficiently generate active species such as radicals necessary for curing the radiation-sensitive resin composition. There is no curing reaction, and it is difficult to obtain satisfactory spacer dimensions and shapes.

An object of the present invention is to provide a spacer having high resolution and high sensitivity and excellent in various performances such as pattern shape, compressive strength, rubbing resistance, and adhesion to a transparent substrate, even under exposure to radiation that does not substantially include a wavelength of less than 350 nm. It is providing the radiation sensitive resin composition for spacers which can be formed so that it may be formed, the spacer formed therefrom, its formation method, and the liquid crystal display element which has this spacer.

The present invention firstly,

[A] A copolymer of (a1) unsaturated carboxylic acid and / or unsaturated carboxylic anhydride with (a2) epoxy group-containing unsaturated compound and (a3) other unsaturated compound,

[B] a polymerizable unsaturated compound,

[C] a biimidazole compound,

[D] a radiation sensitive polymerization initiator having a carbonyl group, and

The radiation sensitive resin composition for spacer formation containing the compound which has [E] dialkylamino group, and / or [F] thiol type compound is contained.

The term "radiation" in the present invention means ultraviolet rays, deep ultraviolet rays, X-rays, electron beams, molecular rays, gamma rays, synchrotron radiation, proton beam rays, and the like.

Secondly, the present invention includes a spacer formed from the radiation-sensitive resin composition for spacer formation.

The present invention includes a method of forming a spacer, which thirdly comprises at least the following steps (a) to (d).

(A) Process of forming the film of the radiation sensitive resin composition for spacer formation of Claim 1 or 2 on a board | substrate.

(B) exposing to at least a portion of the coating a radiation substantially free of a wavelength of less than 350 nm.

(C) Process of developing the film after exposure.

(D) The process of heating the film after image development.

Fourthly, the present invention includes a liquid crystal display device comprising the spacer.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

Radiation-sensitive resin composition for spacer

Hereinafter, each component of the radiation sensitive resin composition for spacers (henceforth a "radiation sensitive resin composition") of this invention is explained in full detail.

[A] Copolymer-

[A] component in the radiation sensitive resin composition of this invention is (a1) unsaturated carboxylic acid and / or unsaturated carboxylic anhydride (henceforth these are called "compound (a1)"), (a2) Copolymer of epoxy group-containing unsaturated compound (hereinafter referred to as "compound (a2)") and (a3) other unsaturated compound (hereinafter referred to as "compound (a3)") (hereinafter referred to as "[A] copolymer") ).

Examples of the compound (a1) include acrylic acid, methacrylic acid, crotonic acid, succinic acid mono (2-acryloyloxyethyl), succinic acid mono (2-methacryloyloxyethyl), and hexahydrophthalic acid mono (2- Monocarboxylic acids such as acryloyloxyethyl) and hexahydrophthalic acid mono (2-methacryloyloxyethyl); Dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, mesaconic acid and itaconic acid; And anhydrides of these dicarboxylic acids.

Among these compounds (a1), acrylic acid, methacrylic acid, maleic anhydride and the like are preferred from the viewpoint of copolymerization reactivity and availability.

The said compound (a1) can be used individually or in mixture of 2 or more types.

The content of the structural unit derived from the compound (a1) in the [A] copolymer is preferably 5 to 50% by weight, particularly preferably 10 to 40% by weight. In this case, if the content rate of the said structural unit is less than 5 weight%, there exists a tendency for the compressive strength, heat resistance, or chemical-resistance of the spacer obtained to fall, and when it exceeds 50 weight%, the storage stability of a radiation sensitive resin composition may fall. There is.

As the compound (a2), for example, glycidyl acrylate, glycidyl methacrylate, α-ethyl acrylate glycidyl, α-n-propyl acrylate glycidyl, α-n-butyl acrylate glycidyl 3,4-epoxybutyl acrylate, 3,4-epoxybutyl methacrylate, 3,4-epoxybutyl acrylate, 3,4-epoxybutyl acrylate, 6,7-epoxyheptyl acrylate, 6,7-epoxyheptyl methacrylate, α- Ethyl acrylate 6,7-epoxyheptyl, acrylic acid β-methylglycidyl, methacrylic acid β-methylglycidyl, acrylic acid β-ethylglycidyl, methacrylic acid β-ethylglycidyl, acrylic acid β-n- Carboxylic acid esters such as propylglycidyl, methacrylic acid β-n-propylglycidyl, acrylic acid 3,4-epoxycyclohexyl, methacrylic acid 3,4-epoxycyclohexyl; ethers such as o-vinyl benzyl glycidyl ether, m-vinyl benzyl glycidyl ether, and p-vinyl benzyl glycidyl ether.

Of these compounds (a2), methacrylic acid glycidyl, methacrylic acid 6,7-epoxyheptyl, methacrylic acid 3,4-epoxycyclohexyl, methacrylic acid β-methylglycidyl, o-vinylbenzyl glyc Cydyl ether, m-vinyl benzyl glycidyl ether, p-vinyl benzyl glycidyl ether, and the like are preferred from the viewpoint of increasing the copolymerization reactivity and the strength of the spacer obtained.

The said compound (a2) can be used individually or in mixture of 2 or more types.

The content of the structural unit derived from the compound (a2) in the [A] copolymer is preferably 10 to 70% by weight, particularly preferably 20 to 60% by weight. In this case, when the content rate of the structural unit is less than 10% by weight, the compressive strength, heat resistance or chemical resistance of the spacer obtained tends to decrease, while when it exceeds 70% by weight, the storage stability of the radiation-sensitive resin composition tends to decrease. There is this.

As the compound (a3), for example, methyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, sec-butyl acrylate, alkyl acrylate esters such as t-butyl acrylate; Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, i-propyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate Alkyl methacrylate esters such as late; Cyclohexyl acrylate, 2-methylcyclohexyl acrylate, tricyclo [5.2.1.0 ^2,6 ] decane-8-ylacrylate (hereinafter “tricyclo [5.2.1.0 ^2,6 ] decane-8-yl” Alicyclic esters of acrylic acid such as "dicyclopentanyl"), 2-dicyclopentanyloxyethyl acrylate, isoboroyl acrylate, and tetrahydrofuryl acrylate; Meta, such as cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, dicyclopentanyl methacrylate, 2-dicyclopentanyloxyethyl methacrylate, isobornyl methacrylate, tetrahydrofuryl methacrylate Alicyclic esters of methacrylic acid; Acrylic acid aryl esters such as phenyl acrylate and benzyl acrylate; Methacrylic acid aryl esters such as phenyl methacrylate and benzyl methacrylate; Dicarboxylic acid diesters such as diethyl maleate, diethyl fumarate and diethyl itaconic acid; Acrylic acid hydroxyalkyl esters such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate; Methacrylic acid hydroxyalkyl esters such as 2-hydroxyethyl methacrylate and 2-hydroxypropyl methacrylate; Aromatic vinyl compounds, such as styrene, (alpha) -methylstyrene, m-methylstyrene, p-methylstyrene, and p-methoxy styrene, acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, acrylamide, and methacryl Amide, vinyl acetate, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, N-cyclohexylmaleimide, N-phenylmaleimide, N-benzylmaleimide, N-succinimidyl- 3-maleimidebenzoate, N-succinimidyl-4-maleimide butyrate, N-succinimidyl-6-maleimide caproate, N-succinimidyl-3-maleimide propionate, N- ( 9-acridinyl) maleimide etc. are mentioned.

Among these compounds (a3), 2-methylcyclohexyl acrylate, t-butyl methacrylate, dicyclopentanyl methacrylate, styrene, p-methoxy styrene, 1,3-butadiene and the like are preferable from the viewpoint of copolymerization reactivity. Do.

The said compound (a3) can be used individually or in mixture of 2 or more types.

The content of the structural unit derived from the compound (a3) in the [A] copolymer is preferably 10 to 80% by weight, particularly preferably 20 to 60% by weight. In this case, when the content rate of the said structural unit is less than 10 weight%, there exists a possibility that the storage stability of a radiation sensitive resin composition may fall, and when it exceeds 80 weight%, developability may fall.

[A] The polystyrene reduced weight average molecular weight (hereinafter referred to as "Mw") by gel permeation chromatography (GPC) of the copolymer is usually 2 × 10 ³ to 5 × 10 ⁵ , preferably 5 × 10 ³ to 1 × 10 ⁵ . In this case, when the Mw of the [A] copolymer is less than 2 × 10 ^3, the compressive strength and the heat resistance of the spacer obtained tend to decrease, while when it exceeds 5 × 10 ⁵ , the developability tends to decrease.

[A] copolymer in this invention can be used individually or in mixture of 2 or more types.

Copolymer [A] can be produced by radical polymerization of compound (a1), compound (a2) and compound (a3), for example, in the presence of a polymerization initiator in a solvent.

[A] As a solvent used for the manufacture of the copolymer, for example

Alcohols such as methanol and ethanol; Ethers such as tetrahydrofuran; Ethylene glycol ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether; Ethylene glycol alkyl ether acetates such as ethylene glycol methyl ether acetate and ethylene glycol ethyl ether acetate; Diethylene glycol ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol ethylmethyl ether; Propylene glycol ethers such as propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol-n-propyl ether and propylene glycol-n-butyl ether; Propylene glycol alkyl ether acetates such as propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol-n-propyl ether acetate, and propylene glycol-n-butyl ether acetate; Propylene glycol alkyl ether propionates such as propylene glycol methyl ether propionate, propylene glycol ethyl ether propionate, propylene glycol-n-propyl ether propionate, and propylene glycol-n-butyl ether propionate; Aromatic hydrocarbons such as toluene and xylene; Ketones such as methyl ethyl ketone, cyclohexanone, and 4-hydroxy-4-methyl-2-pentanone;

Methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, methyl hydroxyacetate, ethyl hydroxyacetate, hydroxyacetic acid n-propyl, hydroxyacetic acid n-butyl, methyl lactate, ethyl lactate, n-propyl lactate , N-butyl lactate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, n-propyl 3-hydroxypropionic acid, n-butyl 3-hydroxypropionic acid, methyl 2-hydroxy-2-methylpropionate, 2 Ethyl hydroxy-2-methylpropionate, methyl 2-hydroxy-3-methylbutyrate, methyl methoxyacetate, ethyl methoxyacetate, methoxyacetic acid n-propyl, methoxyacetic acid n-butyl, methyl ethoxyacetic acid Ethyl ethoxyacetate, ethoxyacetic acid n-propyl, ethoxyacetic acid n-butyl, n-propoxyacetic acid, n-propoxyacetic acid, n-propoxyacetic acid n-propyl, n-propoxyacetic acid n- Butyl, n-butoxy Methyl acetate, n-butoxyacetic acid, n-butoxyacetic acid n-propyl, n-butoxyacetic acid n-butyl, 2-methoxypropionate, ethyl 2-methoxypropionate, 2-methoxypropionic acid n- Propyl, n-butyl 2-methoxypropionate, methyl 2-ethoxypropionate, ethyl 2-ethoxypropionate, n-propyl 2-ethoxypropionate, n-butyl 2-ethoxypropionate, methyl n-propoxypropionate, n-propoxypropionate, n-propoxypropionic acid n-propyl, n-propoxypropionic acid n-butyl, 2-n-butoxypropionate methyl, 2-n-butoxyethylpropionate, 2-n-butoxypropionic acid n-propyl, 2-n-butoxypropionate n-butyl, 3-methoxypropionate, methyl 3-methoxypropionate, 3-methoxypropionic acid n-propyl, 3-methoxypropionic acid n-butyl, 3-e Methyl oxypropionate, ethyl 3-ethoxypropionate, n-propyl 3-ethoxypropionic acid, 3-ethoxypropionic acid n-butyl, 3-n-propoxypropionate, 3-n-propoxypropionate, 3-n-propoxypropionic acid n-propyl, 3-n-propoxypropionic acid n-butyl, 3-n-butoxy And other esters such as methyl propionate, ethyl 3-n-butoxypropionate, n-propyl 3-n-butoxypropionic acid and n-butyl 3-n-butoxypropionate.

Moreover, as a polymerization initiator used for manufacture of [A] copolymer, what is generally known as a radical polymerization initiator can be used, For example, 2,2'- azobisisobutyronitrile, 2,2'- Azobis- (2,4-dimethylvaleronitrile), 2,2'-azobis- (4-methoxy-2,4-dimethylvaleronitrile), 4,4'-azobis (4-cyano Azo compounds such as valeric acid), dimethyl-2,2'-azobis (2-methylpropionate), and 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile); Organic peroxides such as benzoyl peroxide, lauroyl peroxide, t-butylperoxy pivalate, 1,1'-bis- (t-butylperoxy) cyclohexane; Hydrogen peroxide and the like. When using a peroxide as a radical polymerization initiator, you may use a reducing agent together and set it as a redox type initiator.

[B] Polymerizable Unsaturated Compound-

As a polymerizable unsaturated compound in the radiation sensitive resin composition of this invention, bifunctional or more acrylate and methacrylate (henceforth "(meth) acrylate") are preferable.

 As a bifunctional (meth) acrylate, for example, ethylene glycol acrylate, ethylene glycol methacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, 1,9- Nonanediol diacrylate, 1,9-nonanediol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, polypropylene glycol diacrylate, polypropylene glycol dimethacrylate, bisphenoxy Ethanol fluorene diacrylate, bisphenoxy ethanol fluorene dimethacrylate, etc. are mentioned.

In addition, as a commercial item of a bifunctional (meth) acrylate, for example, Aronix M-210, M-240, M-6200 (above, product made from Toa Kosei Co., Ltd.), KAYARAD HDDA, KAYARAD HX -220, copper R-604, UX-2201, UX-2301, UX-3204, UX-3301, UX-4101, UX-6101, UX-7101, UX-8101, MU-2100, MU-4001 Nippon Kayaku Co., Ltd.), Biscot 260, East 312, East 335 HP (above, Osaka Yuki Kagaku Kogyo Co., Ltd. product) etc. are mentioned.

As (meth) acrylate more than trifunctional, for example, trimethylol propane triacrylate, trimethylol propane trimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentaerythritol Tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate , Tri (2-acryloyloxyethyl) phosphate, tri (2-methacryloyloxyethyl) phosphate, or a 9- or more functional (meth) acrylate, having a linear alkylene group and an alicyclic structure, and having two or more isocyanates 3, 4 or 5 acryloyloxy groups and / or methacryloyloxy having a compound having a group and at least one hydroxyl group in the molecule It is reacted with a compound and the like can be obtained urethane acrylate compound.

In addition, as a commercial item of (meth) acrylate more than trifunctional, for example, Aaronic M-309, copper-400, copper-402, copper-405, copper-450, copper-1310, copper-1600, copper- 1960, east-7100, east-8030, east-8060, east-8100, east-8530, east-8560, east-9050, aronix TO-1450 (above, product made by Doa Kosei Co., Ltd.), KAYARAD TMPTA, Copper DPHA, Copper DPCA-20, Copper DPCA-30, Copper DPCA-60, Copper DPCA-120, Copper MAX-3510 (above, made by Nippon Kayaku Co., Ltd.), Biscot 295, Copper 300, Copper 360, Copper As GPT, copper 3PA, copper 400 (above, product made by Osaka Yuki Kagaku Kogyo Co., Ltd.) and urethane acrylate compound, New frontier R-1150 (made by Daiichi Kogyo Seiyaku Co., Ltd.), KAYARAD DPHA- 40H (made by Nippon Kayaku Co., Ltd.) etc. are mentioned.

In this invention, a polymerizable unsaturated compound can be used individually or in mixture of 2 or more types.

The use amount of the polymerizable unsaturated compound in the radiation-sensitive resin composition of the present invention is preferably 30 to 200 parts by weight, particularly preferably 50 to 140 parts by weight based on 100 parts by weight of the [A] copolymer. In this case, when the usage-amount of a polymerizable unsaturated compound is less than 30 weight part, there exists a tendency for the film | membrane of the spacer obtained to fall easily or a fall of strength tends to occur, and when it exceeds 200 weight part, there exists a possibility that the adhesiveness of the spacer obtained may be insufficient.

[C] biimidazole compound-

As the biimidazole compound used in the present invention, for example, a compound represented by the following formula (1) (hereinafter referred to as "biimidazole compound (C1)"), a compound represented by the formula (2) (" Biimidazole type compound (C2) ", etc. are mentioned.

In the formula, X represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 9 carbon atoms, and A represents -COO-R, provided that R represents an alkyl group having 1 to 4 carbon atoms or 6 carbon atoms To an aryl group of to 9), n is an integer of 1 to 3, each m is an integer of 1 to 3.

In formula, X <^1> , X <^2> and X <^3> represent a hydrogen atom, a halogen atom, a cyano group, the C1-C4 alkyl group, or a C6-C9 aryl group mutually independently. However, two or more of X ¹ , X ² and X ³ are not hydrogen atoms at the same time.

As a biimidazole type compound, for example

2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (2-chlorophenyl) -4,4', 5,5 '-Tetrakis (4-ethoxycarbonylphenyl) biimidazole, 2,2'-bis (2-chlorophenyl) -4,4', 5,5'-tetrakis (4-phenoxycarbonylphenyl ) Bimidazole, 2,2'-bis (2,4-dichlorophenyl) -4,4 ', 5,5'- tetrakis (4-ethoxycarbonylphenyl) biimidazole, 2,2'- Bis (2,4-dichlorophenyl) -4,4 ', 5,5'-tetrakis (4-phenoxycarbonylphenyl) biimidazole, 2,2'-bis (2,4,6-trichloro Phenyl) -4,4 ', 5,5'-tetrakis (4-ethoxycarbonylphenyl) biimidazole, 2,2'-bis (2,4,6-trichlorophenyl) -4,4' , 5,5'-tetrakis (4-phenoxycarbonylphenyl) biimidazole, 2,2'-bis (2-cyanophenyl) -4,4 ', 5,5'-tetrakis (4- Ethoxycarbonylphenyl) biimidazole, 2,2'-bis (2-cyanophenyl) -4,4 ', 5,5'-tetrakis (4-phenoxycarbonylphenyl) biimidazole, 2 , 2'-bis (2-methylphenyl) -4,4 ', 5,5'-tetrakis (4-methoxy Carbonylphenyl) biimidazole, 2,2'-bis (2-methylphenyl) -4,4 ', 5,5'-tetrakis (4-ethoxycarbonylphenyl) biimidazole, 2,2'- Bis (2-methylphenyl) -4,4 ', 5,5'-tetrakis (4-phenoxycarbonylphenyl) biimidazole, 2,2'-bis (2-ethylphenyl) -4,4', 5,5'-tetrakis (4-methoxycarbonylphenyl) biimidazole, 2,2'-bis (2-ethylphenyl) -4,4 ', 5,5'-tetrakis (4-ethoxy Carbonylphenyl) biimidazole, 2,2'-bis (2-ethylphenyl) -4,4 ', 5,5'-tetrakis (4-phenoxycarbonylphenyl) biimidazole, 2,2' -Bis (2-phenylphenyl) -4,4 ', 5,5'-tetrakis (4-methoxycarbonylphenyl) biimidazole, 2,2'-bis (2-phenylphenyl) -4,4 ', 5,5'-tetrakis (4-ethoxycarbonylphenyl) biimidazole, 2,2'-bis (2-phenylphenyl) -4,4', 5,5'-tetrakis (4- Biimidazole type compounds (C1) such as phenoxycarbonylphenyl) biimidazole;

2,2'-bis (2,4-dichlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (2,4,6-trichlorophenyl) -4 , 4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (2,4-dibromophenyl) -4,4', 5,5'-tetraphenylbiimidazole, 2, 2'-bis (2,4,6-tribromophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (2,4-dicyanophenyl) -4 , 4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (2,4,6-tricyanophenyl) -4,4', 5,5'-tetraphenylbiimidazole, 2 , 2'-bis (2,4-dimethylphenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (2,4,6-trimethylphenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (2,4-diethylphenyl) -4,4', 5,5'-tetraphenylbiimidazole, 2,2'- Bis (2,4,6-triethylphenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (2,4-diphenylphenyl) -4,4', Biimidazole type, such as 5,5'- tetraphenyl biimidazole and 2,2'-bis (2,4,6- triphenylphenyl) -4,4 ', 5,5'- tetraphenyl biimidazole Compound (C2) etc. are mentioned There.

Among these biimidazole compounds, especially 2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole and 2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetrakis (4-ethoxycarbonylphenyl) biimidazole, 2,2'-bis (2-bromophenyl) -4,4', 5,5'- Tetrakis (4-ethoxycarbonylphenyl) biimidazole, 2,2'-bis (2,4-dichlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2' -Bis (2,4-dibromophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (2,4,6-trichlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (2,4,6-tribromophenyl) -4,4', 5,5'-tetraphenylbiimidazole and the like are preferred. Do.

The biimidazole-based compound (C1) and the biimidazole-based compound (C2) are excellent in solubility in solvents, do not generate foreign matters such as unsealed seafood and precipitates, have high sensitivity, and block wavelengths of 350 nm or less. Even in the radiation, the curing reaction can be sufficiently proceeded by the exposure of a small amount of energy, and an excellent spacer free from missing, missing or undercut patterns can be formed.

In the present invention, the biimidazole-based compound may be used alone or in combination of two or more thereof.

The amount of the non-imidazole compound in the radiation-sensitive resin composition of the present invention is preferably 0.1 to 50 parts by weight, particularly preferably 1 to 35 parts by weight based on 100 parts by weight of the [A] copolymer. In this case, when the amount of the non-imidazole compound is less than 0.1 part by weight, the spacer film obtained tends to be worn down or the strength thereof decreases. On the other hand, when the amount of the non-imidazole compound is greater than 50 parts by weight, the eluate in the liquid crystal increases and the voltage retention rate This tends to decrease.

[D] carbonyl group-containing polymerization initiator-

The component [D] in the present invention is a radiation-sensitive polymerization initiator having a carbonyl group (hereinafter referred to as "[D] carbonyl group-containing polymerization initiator") is a component having the function of adjusting the shape of the spacer to be formed.

[D] As the carbonyl group-containing polymerization initiator, for example, α-diketones such as benzyl and diacetyl; Acyl phosphorus such as benzoin; Acyloin ethers such as benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether; Thioxanthone, 2,4-diethyl thioxanthone, thioxanthone-4-sulfonic acid, benzophenone, 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis (diethylamino) benzo Benzophenones such as phenone; Acetophenone, 4-dimethylaminoacetophenone, α, α'-dimethoxyacetoxybenzophenone, 2,2'-dimethoxy-2-phenylacetophenone, 4-methoxyacetophenone, 2-methyl [4- ( Acetophenones, such as methylthio) phenyl] -2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1; Quinones such as anthraquinone and 1,4-naphthoquinone; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphineoxide, bis (2,4,6-trimethylbenzoyl) phenylforce Phosphine oxides, such as pin oxide, etc. are mentioned.

Moreover, as a commercial item of the [D] carbonyl group containing polymerization initiator, For example, IRGACURE-124, copper-149, copper-184, copper-369, copper-500, copper-651, copper-819, copper-907, copper -1700, east -1000, east-1800, east-1850, east-2959, Darocur-1173, east-1116, east-1664, east-2959, east-4043 (above, product made in Chiba specialty chemicals company), KAYACURE-DETX, East-MBP, East-DMBI, East-EPA, East-OA (above, made by Nippon Kayaku Co., Ltd.), LUCIRIN TPO (made by BASF Co. LTD.), VICURE-10, East-55 (more than And STAUFFER Co. LTD.

[D] carbonyl group containing polymerization initiator can be used individually or in mixture of 2 or more types in this invention.

In the radiation-sensitive resin composition of the present invention, the amount of the [D] carbonyl group-containing polymerization initiator to be used is preferably 1 to 50 parts by weight, particularly preferably 3 to 30 parts by weight based on 100 parts by weight of the [A] copolymer. . In this case, when the amount of the [D] carbonyl group-containing polymerization initiator is less than 1 part by weight, the spacer film to be obtained tends to be worn out or a defect in the pattern shape tends to occur. There is a fear that the size exceeds the allowable range.

[E] Compound Having Dialkylamino Group-

The compound having a dialkylamino group in the radiation-sensitive resin composition of the present invention is not particularly limited as long as it has a function of increasing or decreasing the [C] biimidazole compound, and as a preferable compound, for example, 4,4 ' -Bis (dimethylamino) benzophenone, 4,4'-bis (diethylamino) benzophenone, ethyl p-dimethylaminobenzoic acid, ethyl p-diethylaminobenzoic acid, p-dimethylaminobenzoic acid i-amyl, p-di Aromatic compounds, such as ethyl amino benzoic acid i-amyl, are mentioned. However, as in the case of 4,4'-bis (dimethylamino) benzophenone or 4,4'-bis (diethylamino) benzophenone, a compound having a dialkylamino group is included in the category of the [D] carbonyl group-containing polymerization initiator. In this case, a compound different from the above-mentioned [D] component is used.

Among the compounds having these dialkylamino groups, 4,4'-bis (diethylamino) benzophenone is particularly preferable.

The compound which has a dialkylamino group in this invention can be used individually or in mixture of 2 or more types.

 The amount of the compound having a dialkylamino group in the radiation-sensitive resin composition of the present invention is preferably 0.1 to 50 parts by weight, particularly preferably 1 to 20 parts by weight based on 100 parts by weight of the [A] copolymer. In this case, when the amount of the compound having a dialkylamino group is less than 0.1 part by weight, the spacer film to be obtained tends to be worn out or a defect in the pattern shape tends to occur. Tend to lose.

[F] thiol compounds-

The thiol compound in the radiation sensitive resin composition of the present invention is a component having a function of donating hydrogen radicals to the [C] biimidazole compound.

That is, the [C] biimidazole-based compound generates imidazole radicals by being sensitized and cleaved by a compound having a [E] dialkylamino group, but in this case, a high radical polymerization initiation capacity is not expressed unless a thiol-based compound is present. The resulting spacers often have an undesirable shape such as an inverted taper shape. However, by adding a thiol-based compound to a system in which a [C] biimidazole compound and a compound having a [E] dialkylamino group coexist, a hydrogen radical is donated to the imidazole radical, and the imidazole radical is converted into a neutral imidazole. At the same time as the conversion, a component having a sulfur radical having a high polymerization initiation capacity is generated, whereby the shape of the spacer can be made into a more preferable forward taper phase.

As a thiol type compound, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 2-mercaptobenzoimidazole, 2-mercapto-5-methoxybenzothiazole, 2-mercapto, for example Aromatic compounds such as -5-methoxybenzoimidazole; Aliphatic monothiol compounds such as 3-mercaptopropionic acid, 3-mercaptopropionic acid methyl, 3-mercaptopropionic acid ethyl, and 3-mercaptopropionic acid n-octyl; Aliphatic polythiol compounds such as 3,6-dioxa-1,8-octanedithiol, pentaerythritol tetra (mercaptoacetate), pentaerythritol tetra (3-mercaptopropionate), and the like. Can be.

The amount of the thiol-based compound used in the radiation-sensitive resin composition of the present invention is preferably 0.1 to 50 parts by weight, particularly preferably 1 to 20 parts by weight based on 100 parts by weight of the [C] biimidazole compound. In this case, when the amount of the thiol-based compound is less than 0.1 part by weight, the spacer film to be obtained tends to be worn out or defects in the pattern shape tend to occur. On the other hand, when the amount of the thiol compound exceeds 50 parts by weight, the pattern defect tends to occur easily. have.

Arbitrary Additives

The radiation sensitive resin composition of this invention can mix | blend arbitrary additives other than the above, for example, an adhesion | attachment adjuvant, surfactant, a storage stabilizer, a heat resistance improving agent, etc. in the range which does not impair the effect of this invention as needed.

The said adhesion aid is a component used in order to improve the adhesiveness of the formed spacer and a board | substrate.

As such an adhesion aid, a functional silane coupling agent having reactive functional groups such as carboxyl group, methacryloyl group, vinyl group, isocyanate group and epoxy group is preferable, and examples thereof include trimethoxysilylbenzoic acid and γ-methacryloxypropyl tri. Methoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatepropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimeth Oxysilane, etc. are mentioned.

These adhesion aids can be used individually or in mixture of 2 or more types.

The blending amount of the adhesion aid is preferably 20 parts by weight or less, and more preferably 10 parts by weight or less based on 100 parts by weight of the [A] copolymer. In this case, when the compounding quantity of an adhesion | attachment adjuvant exceeds 20 weight part, there exists a tendency for image development residue to occur easily.

In addition, the said surfactant is a component used in order to improve applicability | paintability.

As such surfactant, a fluorochemical surfactant, silicone type surfactant, etc. are preferable, for example.

As the fluorine-based surfactant, a compound having a fluoroalkyl group and / or a fluoroalkylene group in at least one of terminal, main chain and side chain is preferable, and examples thereof include 1,1,2,2-tetrafluoro -n-octyl (1,1,2,2-tetrafluoro-n-propyl) ether, 1,1,2,2-tetrafluoro-n-octyl (n-hexyl) ether, hexaethylene glycol di ( 1,1,2,2,3,3-hexafluoro-n-pentyl) ether, octaethylene glycol di (1,1,2,2-tetrafluoro-n-butyl) ether, hexapropylene glycol di ( 1,1,2,2,3,3-hexafluoro-n-pentyl) ether, octapropylene glycoldi (1,1,2,2-tetrafluoro-n-butyl) ether, perfluoro-n Sodium dodecanesulfonate, 1,1,2,2,3,3-hexafluoro-n-decane, 1,1,2,2,8,8,9,9,10,10-decafluoro- n-dodecane, sodium fluoroalkylbenzene sulfonates, sodium fluoroalkyl phosphates, sodium fluoroalkyl carboxylic acids, diglycerin tetrakis (Fluoroalkyl polyoxyethylene ether) s, fluoroalkyl ammonium iodides, fluoroalkyl betaines, other fluoroalkyl polyoxyethylene ethers, perfluoroalkyl polyoxyethanols, perfluoroalkyl alkoxyls And carboxylic acid fluoroalkyl esters.

Moreover, as a commercial item of a fluorine-type surfactant, BM-1000, BM-1100 (above, BM CHEMIE company make), Megapack F142D, copper F172, copper F173, copper F183, copper F178, copper F191, copper F471, Copper F476 (above, Dai Nippon Ink Chemical Co., Ltd.), fluoride FC-170C, copper -171, copper -430, copper -431 (above, Sumitomo 3M Co., Ltd.), Suplon S-112 , East-113, East-131, East-141, East-145, East-382, Suflon SC-101, East-102, East-103, East-104, East-105, East-106 (above, Asahi Glass Co., Ltd.), F-top EF301, copper 303, copper 352 (above, new baby Kasei Co., Ltd.), butanegent FT-100, copper-110, copper-140A, copper-150, copper-250, Copper-251, copper-300, copper-310, copper-400S, butanegent FTX-218, copper-251 (above, made by Neos), etc. are mentioned.

As said silicone type surfactant, Toray silicon DC3PA, copper DC7PA, copper SH11PA, copper SH21PA, copper SH28PA, copper SH29PA, copper SH30PA, copper SH-190, copper SH-193, copper SZ-6032, copper SF- 8428, copper DC-57, copper DC-190 (above, made by Toray Dow Corning Silicon Co., Ltd.), TSF-4440, TSF-4300, TSF-4445, TSF-4446, TSF-4460, TSF-4452 ( As mentioned above, what is marketed by brand names, such as GE Toshiba Silicone Co., Ltd., are mentioned.

Moreover, as surfactant other than the above, Polyoxyethylene alkyl ether, such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether; Polyoxyethylene aryl ethers such as polyoxyethylene-n-octylphenyl ether and polyoxyethylene-n-nonylphenyl ether; Nonionic surfactants such as polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate, organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), (meth ) Acrylic acid copolymer polyflo no. 57, East No. 95 (above, Kyoeisha Chemical Co., Ltd. product) etc. are mentioned.

These surfactant can be used individually or in mixture of 2 or more types.

The compounding quantity of surfactant is 1.0 weight part or less, More preferably, it is 0.5 weight part or less with respect to 100 weight part of [A] copolymers. In this case, when the compounding quantity of surfactant exceeds 1.0 weight part, there exists a tendency for film | membrane stain to arise easily.

Examples of the storage stabilizer include sulfur, quinones, hydroquinones, polyoxy compounds, amines, nitronitroso compounds and the like, and more specifically 4-methoxyphenol, N-nitroso-N- Phenyl hydroxyl amine aluminum etc. are mentioned.

These storage stabilizers can be used individually or in mixture of 2 or more types.

The compounding quantity of a storage stabilizer is 3.0 weight part or less with respect to 100 weight part of [A] copolymers, More preferably, it is 0.5 weight part or less. In this case, when the compounding quantity of a storage stabilizer exceeds 3.0 weight part, there exists a possibility that a sensitivity may fall and a pattern shape may deteriorate.

In addition, examples of the heat resistance improver include N- (alkoxymethyl) glycoluril compounds, N- (alkoxymethyl) melamine compounds, compounds having two or more epoxy groups, and the like.

Examples of the N- (alkoxymethyl) glycoluril compound include N, N, N, N-tetra (methoxymethyl) glycoluril, N, N, N, N-tetra (ethoxymethyl) glycoluril, N, N, N, N-tetra (n-propoxymethyl) glycoluril, N, N, N, N, N-tetra (i-propoxymethyl) glycoluril, N, N, N, N-tetra (n- Butoxymethyl) glycoluril, N, N, N, N-tetra (t-butoxymethyl) glycoluril, etc. are mentioned.

Among these N- (alkoxymethyl) glycoluril compounds, N, N, N, N-tetra (methoxymethyl) glycoluril is preferable.

Examples of the N- (alkoxymethyl) melamine compound include N, N, N, N, N, N-hexa (methoxymethyl) melamine, N, N, N, N, N, N-hexa (e) Methoxymethyl) melamine, N, N, N, N, N, N-hexa (n-propoxymethyl) melamine, N, N, N, N, N, N-hexa (i-propoxymethyl) melamine, N , N, N, N, N, N-hexa (n-butoxymethyl) melamine, N, N, N, N, N, N-hexa (t-butoxymethyl) melamine and the like.

Among these N- (alkoxymethyl) melamine compounds, N, N, N, N, N, N-hexa (methoxymethyl) melamine is preferable, and as the commercial item, for example, Nicarac N-2702, copper MW -30 M (above Sanwa Chemical Co., Ltd.) etc. are mentioned.

Examples of the compound having two or more epoxy groups include ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, triethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, and propylene glycol. Diglycidyl ether, dipropylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol digly Cylyl ether, glycerin diglycidyl ether, trimethylol propane triglycidyl ether, hydrogenated bisphenol A diglycidyl ether, bisphenol A diglycidyl ether, etc. are mentioned.

Moreover, as a commercial item of the compound which has two or more epoxy groups, for example, epolite 40E, copper 100E, copper 200E, copper 70P, copper 200P, copper 400P, copper 1500NP, copper 80MF, copper 100MF, copper 1600, copper 3002 And 4,000 (more than Kyueisha Chemical Co., Ltd. make) etc. are mentioned.

These heat resistance improvers can be used individually or in mixture of 2 or more types.

It is preferable to use it for using the radiation sensitive resin composition of this invention as a composition solution melt | dissolved in the suitable solvent.

As said solvent, what melt | dissolves each essential component and arbitrary additive component of the radiation sensitive resin composition of this invention uniformly, and does not react with each component is used.

As such a solvent, for example

Alcohols such as methanol and ethanol; Ethers such as tetrahydrofuran; Ethylene glycol ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether; Ethylene glycol alkyl ether acetates such as ethylene glycol methyl ether acetate and ethylene glycol ethyl ether acetate; Diethylene glycol ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether and diethylene glycol ethyl methyl ether;

Propylene glycol ethers such as propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol n-propyl ether and propylene glycol n-butyl ether; Propylene glycol alkyl ether acetates such as propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol n-propyl ether acetate, and propylene glycol n-butyl ether acetate; Propylene glycol alkyl ether propionates such as propylene glycol methyl ether propionate, propylene glycol ethyl ether propionate, propylene glycol n-propyl ether propionate, and propylene glycol n-butyl ether propionate;

Aromatic hydrocarbons such as toluene and xylene; Ketones such as methyl ethyl ketone, cyclohexanone, and 4-hydroxy-4-methyl-2-pentanone; Methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, methyl hydroxyacetate, ethyl hydroxyacetate, hydroxy N-propyl acetate, n-butyl hydroxyacetic acid, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, n-propyl 3-hydroxypropionate And other esters such as 3-hydroxypropionic acid n-butyl, 3-butoxypropionate methyl, 3-butoxyethyl propionate, 3-butoxypropionic acid n-propyl, and 3-butoxypropionic acid n-butyl. have.

Among these solvents, ethylene glycol ethers, ethylene glycol alkyl ether acetates, diethylene glycol ethers, and other esters are preferable from solubility, reactivity with each component, and ease of coating film formation.

The said solvent can be used individually or in mixture of 2 or more types.

In this invention, a high boiling point solvent can also be used together with the said solvent.

As the high boiling point solvent, for example, N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone , Dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether, acetonyl acetone, isophorone, capric acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, Diethyl maleate, gamma -butyrolactone, ethylene carbonate, propylene carbonate, phenyl cellosolve acetate, and the like.

These high boiling point solvents can be used individually or in mixture of 2 or more types.

In addition, the composition solution prepared as described above may be used by filtration with a Millipore filter having a pore size of about 0.5 μm.

Formation method of spacer

Next, the method of forming the spacer of this invention using the radiation sensitive resin composition of this invention is demonstrated.

The formation method of the spacer of this invention includes the process of at least (a)-(d) below.

(A) Process of forming the film of the radiation sensitive resin composition of this invention on a board | substrate.

(B) exposing radiation not containing a wavelength of less than 350 nm to at least a portion of the film.

(C) Process of developing the film after exposure.

(D) The process of heating the film after image development.

Hereinafter, each of these steps will be described in order.

(A) Process

A transparent conductive film is formed on one surface of a transparent substrate, and after apply | coating the composition solution of the radiation sensitive resin composition of this invention on this transparent conductive film, a film is formed by heating (prebaking) a coating surface.

As a transparent substrate used for formation of a spacer, a glass substrate, a resin substrate, etc. are mentioned, for example, More specifically, glass substrates, such as a soda-lime glass and an alkali free glass; And resin substrates containing plastics such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate, and polyimide.

Transparent conductive films provided on one side of the transparent substrate include NESA films containing tin oxide (SnO ₂ ) (registered trademark of PPG, USA) and ITO containing indium tin oxide (In ₂ O ₃ -SnO ₂ ). And the like.

As a coating method of a composition solution, the appropriate method, such as the spray method, the roll coating method, the rotation coating method, can be employ | adopted, for example.

In addition, although the conditions of prebaking differ also with kinds, mixing | blending ratio, etc. of each component, it is about 1 to 15 minutes at 70-120 degreeC normally.

-(B) process-

Subsequently, at least a portion of the formed film is exposed to radiation that does not substantially include a wavelength of less than 350 nm. In this case, when exposing to a part of film, it exposes through a predetermined pattern mask. In the present invention, by reducing the radiation of a wavelength of less than 350 nm having a high energy, it is possible to effectively suppress the reduction in the life of the mirror used in the exposure machine.

As the radiation used for exposure, visible rays, ultraviolet rays, ultraviolet rays, and the like can be used. However, it is preferable to block less than 350 nm from radiation having a wavelength in the range of 190 to 450 nm.

The exposure amount is a value measured by an illuminometer (OAI model 356, manufactured by OAI Optical Associates Inc.) of the intensity of the exposed radiation at 365 nm, and is usually 100 to 10,000 J / m 2, preferably 1,500 to 3,000 J / m 2. to be.

Although it does not specifically limit as a method of blocking the wavelength below 350 nm of radiation, For example, the method of using a filter can be employ | adopted.

As said filter, the ultraviolet transmission filter "UV-35" by Toshiba Glass Co., Ltd. can be used, for example.

The emission spectrum of the mercury lamp which transmitted the ultraviolet transmission filter "UV-35" (thick line) and the emission spectrum of the mercury lamp which were not transmitted (a thin line, but the emission spectrum of 350 nm or more partially overlaps with a thick line). 1 is shown. Although the wavelength of less than 350 nm is included in the light emission spectrum (thick line) of FIG. 1, the relative intensity and cumulative area are small enough, and it does not adversely affect the lifetime of the mirror used for an exposure machine.

-(C) process-

Next, by developing the film after exposure, an unnecessary part is removed and a predetermined pattern is formed.

As a developing solution used for image development, For example, inorganic alkalis, such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia; Aliphatic primary amines such as ethylamine and n-propylamine; Aliphatic secondary amines such as diethylamine and di-n-propylamine; Aliphatic tertiary amines such as trimethylamine, methyldiethylamine, dimethylethylamine and triethylamine; Pyrrole, piperidine, N-methylpiperidine, N-methylpyrrolidine, 1,8-diazabicyclo [5.4.0] -7-undecene, 1,5-diazabicyclo [4.3.0] Alicyclic tertiary amines such as -5-nonene; Aromatic tertiary amines such as pyridine, collidine, lutidine and quinoline; Alkanolamines, such as dimethylethanolamine, methyl diethanolamine, and triethanolamine; Aqueous solutions of alkaline compounds, such as quaternary ammonium salts, such as tetramethylammonium hydroxide and tetraethylammonium hydroxide, can be used.

In addition, an aqueous solution of the alkaline compound may be used by adding an appropriate amount of a water-soluble organic solvent such as methanol and ethanol and / or a surfactant.

As a developing method, any of a paddle method, an immersion method, a shower method, etc. may be sufficient, and developing time is about 10 to 180 second at normal temperature normally.

After the development, for example, washing with running water for 30 to 90 seconds, followed by air drying with, for example, compressed air or compressed nitrogen, forms a desired pattern.

-(D) process-

Subsequently, the obtained pattern is heated at a predetermined temperature, for example, 100 to 160 ° C. for a predetermined time, for example, 5 to 30 minutes on a hot plate, and 30 to 180 minutes in an oven, for example, by a heating device such as a hot plate or an oven. By heating (post-baking), a predetermined spacer can be obtained.

In the conventional radiation-sensitive resin composition used for forming the spacer, the obtained spacer could not exhibit sufficient performance unless the heat treatment was performed at a temperature of about 180 to about 200 ° C. or more, but the radiation-sensitive resin composition of the present invention had a conventional heating temperature. It can be made at a lower temperature, and as a result, a spacer excellent in various performances such as yellowing or deformation of the resin substrate and excellent in compressive strength, rubbing resistance at the time of liquid crystal alignment, and adhesion to a transparent substrate can be obtained.

Liquid crystal display device

Next, the liquid crystal display element of this invention is demonstrated.

The liquid crystal display element of this invention is equipped with the spacer formed as mentioned above.

Although it does not specifically limit as a structure of a liquid crystal display element, For example, as shown in FIG. 2, two alignment films which form the color filter layer and the spacer of this invention on a transparent substrate, and are arrange | positioned through a liquid crystal layer, opposing transparent The structure which has an electrode, an opposing transparent substrate, etc. is mentioned. In addition, as shown in FIG. 2, a protective film can also be provided on a polarizing plate and a color filter layer as needed.

In addition, as shown in FIG. 3, a color filter layer and a spacer of the present invention may be formed on a transparent substrate, and may be formed into a TN-TFT type liquid crystal display element by facing a thin film transistor (TFT) array through an alignment layer and a liquid crystal layer. Also in this case, a protective film can be provided on a polarizing plate and a color filter layer as needed.

<Example>

Hereinafter, an Example is given and embodiment of this invention is described further more concretely.

Synthesis Example 1

5 parts by weight of 2,2'-azobis (2,4-dimethylvaleronitrile) and 250 parts by weight of diethylene glycol methylethyl ether were added to a flask equipped with a cooling tube and a stirrer, followed by 20 parts by weight of styrene and methacryl 17 parts by weight of acid, 18 parts by weight of dicyclopentanyl methacrylate, and 45 parts by weight of glycidyl methacrylate were substituted for nitrogen, and then the temperature of the reaction solution was raised to 70 ° C. with slow stirring, and the temperature was maintained for 4 hours. And polymerizing to obtain a resin solution containing the [A] copolymer. Solid content concentration of this resin solution was 28.4 weight%, and Mw of the obtained [A] copolymer was 16,000. This [A] copolymer is called "copolymer (A-1)".

Mw of copolymer (A-1) and copolymer (A-2) mentioned later was measured using GPC (gel permeation chromatography) HLC-8020 (made by Tosoh Corporation).

Synthesis Example 2

4 parts by weight of 2,2'-azobis (2,4-dimethylvaleronitrile) and 250 parts by weight of diethylene glycol methylethyl ether were added to a flask equipped with a cooling tube and a stirrer, followed by 5 parts by weight of styrene and methacryl 16 parts by weight of acid, 34 parts by weight of dicyclopentanyl methacrylate and 40 parts by weight of glycidyl methacrylate were substituted for nitrogen, and then 5 parts by weight of 1,3-butadiene was added thereto, and the temperature of the reaction solution was slowly stirred. It heated up to 70 degreeC, hold | maintained this temperature for 4 hours, and obtained the resin solution containing the [A] copolymer. Solid content concentration of this resin solution was 28.6 weight%, and Mw of the obtained [A] copolymer was 15,000. This [A] copolymer is referred to as "copolymer (A-2)".

<Example 1>

(I) Preparation of a radiation sensitive resin composition

As the component (A), the resin solution obtained in Synthesis Example 1 was used as a copolymer (A-1) in 100 parts by weight (solid content), and as the component (B), dipentaerythritol hexaacrylate (trade name KAYARAD DPHA, Nippon Kayaku ( Note) agent) 80 parts by weight, 10 parts by weight of 2,2'-bis (2,4-dichlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole as the component [C], [D] As a component, 15 parts by weight of 2-methyl [4- (methylthio) phenyl] -2-morpholino-1-propane (trade name Irgacure 907, manufactured by Chiba Specialty Chemicals Co., Ltd.), 4 as [E] component 10 parts by weight of, 4'-bis (dimethylamino) benzophenone, 5 parts by weight of 2-mercaptobenzothiazole as the [F] component, 5 parts by weight of γ-glycidoxypropyltrimethoxysilane as an adhesion aid, and a surfactant 0.5 parts by weight of FTX-218 (trade name, manufactured by Neos Co., Ltd.), 0.5 parts by weight of 4-methoxyphenol as a storage stabilizer, and propylene glycol monomethyl so as to have a solid content concentration of 30% by weight. It was dissolved in Terre acetate, and an opening diameter of 0.5 mm ㎛ filtered through a pore filter to prepare a composition solution.

(II) Formation of spacer

After using the spinner on the alkali free glass substrate and apply | coating the said composition solution, it prebaked for 3 minutes on the 90 degreeC hotplate, and formed the film of 6.0 micrometers in film thickness.

Subsequently, the obtained film was a UV light having a strength at 365 nm of 250 W / m 2 and passing through the ultraviolet transmission filter "UV-35" manufactured by Toshiba Glass Co., Ltd. through a mask of a remaining pattern of 10 µm edges. Was exposed for 10 seconds. Thereafter, the solution was developed at 25 ° C. for 60 seconds with a 0.05% by weight aqueous solution of potassium hydroxide, and then washed with pure water for 1 minute. Then, the spacer of a predetermined pattern was formed by baking after baking at 150 degreeC for 120 minutes in oven.

(III) evaluation of resolution

When the pattern was formed in II, the case where the remaining pattern could be resolved was evaluated as good (○), and the case where the resolution could not be resolved as defective (×). The evaluation results are shown in Table 3 below.

(IV) evaluation of sensitivity

About the pattern obtained by said II, the case where the residual film rate (film thickness after image development x 100 / initial film thickness after development) is 90% or more was good ((circle)) and the case where it was less than 90% was evaluated as defect (x). Table 3 shows the results of the evaluation.

(V) Evaluation of pattern shape

The cross-sectional shape of the pattern obtained in said II was observed with the scanning electron microscope, and it evaluated by any of A-D shown in FIG. At this time, when the pattern edge is in a forward taper shape or a vertical shape like A or B, it can be said that the pattern shape as a spacer is favorable. On the other hand, as shown in C, the sensitivity is insufficient, the residual film ratio is low, the cross-sectional dimension is smaller than that of A and B, and when the bottom of the cross-sectional shape is a flat semiconvex lens shape, the pattern shape as a spacer is poor. Also, as shown in D, even when the cross-sectional shape is in the reverse tapered shape, the pattern shape as a spacer is regarded as defective because there is a high possibility that the pattern is peeled off during the subsequent rubbing treatment. Table 3 shows the results of the evaluation.

(VI) evaluation of compressive strength

About the pattern obtained by said II, the deformation amount at the time of applying the load of 10 mN by the planar indenter of 50 micrometers in diameter using a microcompression tester (MCTM-200, the Shimadzu Corporation make) measured temperature 23 Measured at ℃. When this value is 0.5 or less, the compressive strength can be said to be good. Table 3 shows the results of the evaluation.

 (VII) evaluation of rubbing resistance

After apply | coating AL 3046 (brand name, JSR Corporation make) to the board | substrate which formed the pattern obtained by said II as a liquid crystal aligning agent using the printing machine for liquid crystal aligning film application, it dried at 180 degreeC for 1 hour, and dried film thickness of 0.05 micrometer. The coating film of the orientation agent of was formed. Then, using the rubbing machine which has the roll which wound the cloth made from polyamide to this coating film, the rubbing process was performed at the roll speed of 500 rpm and the moving speed of 1 cm / sec of a stage. At this time, it was evaluated whether the pattern was cut or peeled off. Table 3 shows the results of the evaluation.

(VIII) Evaluation of adhesion

Except not having used the mask of the remaining pattern, it carried out similarly to said II and formed the cured film. Then, in the adhesion test of JISK-5400 (1900) 8.5, it evaluated by the 8.5 * 2 checker taping method. At this time, Table 3 shows the number of the remaining tiles among the 100 tiles.

<Examples 2 to 14>

Each composition solution was produced and evaluated similarly to Example 1 except having used each component shown in Table 1 as [A]-[F] component. Table 3 shows the results of the evaluation.

<Comparative Examples 1 to 9>

Each composition solution was produced and evaluated similarly to Example 1 except having used each component shown in Table 2 as [A]-[F] component. Table 3 shows the results of the evaluation.

In Table 1 and Table 2, each component other than a copolymer (A-1) and a copolymer (A-2) is as follows.

[B] component

B-1: dipentaerythritol hexaacrylate

[C] component

C-1: 2,2'-bis (2,4-dichlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole

C-2: 2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole

[D] component

D-1: 2-methyl [4- (methylthio) phenyl] -2-morpholino-1-propaneone

D-2: 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1

[E] component

E-1: 4,4'-bis (dimethylamino) benzophenone

[F] component

F-1: 2-mercaptobenzothiazole

F-2: pentaerythritol tetra (mercaptoacetate)

The radiation sensitive resin composition for spacer formation of this invention is high resolution and high sensitivity also in exposure by the radiation which does not contain the wavelength of 350 nm or less substantially, and it is a pattern shape, compressive strength, rubbing tolerance, adhesiveness with a transparent substrate, etc. It is possible to easily form a spacer excellent in various performances, and to lower the heating temperature after development in forming the spacer, and does not cause yellowing or deformation of the resin substrate.

Moreover, the liquid crystal display element of this invention is equipped with the spacer which was excellent in various performances, such as a pattern shape, compressive strength, rubbing tolerance, adhesiveness with a transparent substrate, and can express high reliability over a long term.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which illustrates the emission spectrum (thick line) of the mercury lamp which permeate | transmitted the ultraviolet transmission filter "UV-35", and the emission spectrum (thin line) of the mercury lamp which was not transmitted.

It is a schematic diagram which shows an example of the structure of a liquid crystal display element.

It is a schematic diagram which shows the other example of the structure of a liquid crystal display element.

It is a schematic diagram which illustrates the cross-sectional shape of a spacer.

Claims (5)

[A] a copolymer of (a1) unsaturated carboxylic acid and / or unsaturated carboxylic anhydride with (a2) epoxy group-containing unsaturated compound and (a3) other unsaturated compound, [B] a polymerizable unsaturated compound, [C] a biimidazole compound, [D] a radiation sensitive polymerization initiator having a carbonyl group, and [E] A radiation sensitive resin composition for forming a spacer, comprising a compound having a dialkylamino group and / or a [F] thiol compound. [C] The biimidazole compound is a compound represented by the following general formula (1) or (2), The radiation sensitive resin composition for spacer formation of Claim 1 characterized by the above-mentioned. <Formula 1> In the formula, X represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 9 carbon atoms, and A represents -COO-R, provided that R represents an alkyl group having 1 to 4 carbon atoms or 6 carbon atoms To an aryl group of to 9), n is an integer of 1 to 3, each m is an integer of 1 to 3. <Formula 2> Wherein X ¹ , X ² and X ³ independently represent a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 9 carbon atoms, provided that X ¹ , X ² and X ³ Two or more of them are not hydrogen atoms at the same time. The spacer formed from the radiation sensitive resin composition for spacer formation of Claim 1 or 2. A method of forming a spacer comprising at least the steps (a) to (d) below. (A) process of forming the film of the radiation sensitive resin composition for spacer formation of Claim 1 or 2 on a board | substrate, (B) exposing radiation to the at least a portion of the film that does not substantially include a wavelength of less than 350 nm, (C) developing the film after exposure, and (D) The process of heating the film after image development. The liquid crystal display element provided with the spacer of Claim 3.