KR101169474B1 - Radiation sensitive resin composition, spacer, and its forming method, and liquid crystal display device - Google Patents

Abstract

The present invention can faithfully reproduce the design size of the mask pattern at high sensitivity, and excellent adhesion to the substrate, can achieve a sufficient spacer shape and film thickness with an exposure dose of 1500 J / ㎡ or less, and the problem of precipitation of the photopolymerization initiator in the developer It provides not only the solution but also the radiation sensitive resin composition which can form the spacer for liquid crystal display elements excellent also in intensity | strength, heat resistance, etc.

Means for solving the problems of the prior art in the present invention,

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

[B] a polymerizable compound having an ethylenically unsaturated bond and

[C] photopolymerization initiator

And a content of the photopolymerization initiator [C] is 0.1 to 5 parts by weight based on 100 parts by weight of [B].

Radiation-sensitive resin composition, spacer, liquid crystal display element, ethylenically unsaturated carboxylic acid, epoxy group containing ethylenically unsaturated compound, photoinitiator

Description

A radiation sensitive resin composition, a spacer, the formation method thereof, and a liquid crystal display element TECHNICAL FIELD [RADIATION SENSITIVE RESIN COMPOSITION, SPACER, AND ITS FORMING METHOD]

1 is a schematic diagram illustrating a cross-sectional shape of a spacer.

TECHNICAL FIELD This invention relates to a radiation sensitive resin composition, a spacer, its formation method, and a liquid crystal display element.

In the liquid crystal display device, spacer particles such as glass beads and plastic beads having a predetermined particle diameter are conventionally used to maintain a constant gap (cell gap) between two substrates, but these spacer particles are transparent substrates such as glass substrates. Since the particles are irregularly dispersed in the phase, when the spacer particles are present in the pixel formation region, there is a problem that the spacer particles are taken out or the incident light is scattered and the contrast of the liquid crystal display element is lowered.

Therefore, in order to solve this problem, a method of forming a spacer through photolithography has been used. In the above method, the radiation-sensitive resin composition is applied onto a substrate and developed after exposure to ultraviolet rays through a predetermined mask to form a dot or stripe-shaped spacer, whereby the spacer is formed only at a predetermined place other than the pixel formation region. The problem as described above is basically solved since it can be.

However, in the case of forming a spacer through a photographic plate on a substrate used in an actual spacer forming process, for example, a color filter or the like, a proximity exposure machine is often used. In the case of such close exposure, it is ideal to provide a predetermined gap between the mask and the substrate coated with the photosensitive resin composition and to expose the mask in a pattern as it is. However, there has been a problem that the gap is filled with air or nitrogen and the light passing through the opening (transparent portion) of the mask diffuses and spreads in the gap, so that the exposure is wider than the design size of the mask pattern.

Therefore, the present applicant has already disclosed in Japanese Patent Laid-Open No. 2001-261761 to solve this problem, 1,2-octanedione-1- [4- (phenylthio) phenyl]-as a photopolymerization initiator of radiation-sensitive resin composition. The use of 2- (O-benzoyl oxime) reveals that it is possible to faithfully reproduce the design size of the mask pattern even by proximity exposure, and to form a spacer for a display panel excellent in strength and heat resistance.

In addition, although the cell gap needs to be controlled more accurately with the increase in size of the liquid crystal display element, if the adhesion formed between the film formed from the radiation-sensitive resin composition for the spacer and the substrate is insufficient, the formed spacer is shifted from the substrate, resulting in a cell gap. It is impossible to keep accurate. In the liquid crystal display panel, the aperture ratio of pixels is advanced, and the area of the black matrix area | region which can arrange a spacer is also getting smaller. Therefore, even in the case where the spacer enters the pixel region to some extent, even if the color tone of the pixel is not damaged, higher transparency is required for the spacer.

 However, conventional radiation-sensitive resin compositions used in the formation of spacers, including those described in Japanese Unexamined Patent Publication No. 2001-261761, are not always sufficient in terms of adhesion to the substrate and transparency, and therefore, their The development of the radiation sensitive resin composition which also has the characteristic is calculated | required strongly. In addition, in recent years, due to the larger area of the liquid crystal display device or the improvement in productivity, the enlargement of mother glass substrates has been progressing. In the conventional substrate size (about 680 × 880 mm), since the substrate size is smaller than the mask size, it is possible to cope with the batch exposure method. However, in large substrates (e.g., about 1500 x 1800 mm), it is almost impossible to manufacture a mask having the same size as this substrate size and it is difficult to cope with the batch exposure method. Therefore, a stepwise exposure method has been proposed as an exposure method corresponding to a large substrate. However, the stepwise exposure method requires several exposures to one substrate and takes time for position alignment and step movement each time. In the stepwise exposure method, compared with the batch exposure method, a reduction in throughput is concerned. Although exposure sensitivity of about 3000 J / m <2> is permissible in the package exposure system, exposure sensitivity is required to be 1500 J / m <2> or less in the stepwise exposure system. However, it is difficult to achieve sufficient spacer shape and film thickness with an exposure dose of 1500 J / m 2 or less in existing materials.

In recent years, precipitation of insoluble components in a developing solution has become a problem. In the radiation-sensitive resin composition used in conventional spacer formation, many photopolymerization initiators which are insoluble in alkaline developing solutions are used. However, in order to achieve the high throughput, the sensitivity of the photopolymerization initiator can be set high to achieve high sensitivity. In this case, after dissolving and removing the unexposed part after spacer formation, a photoinitiator may precipitate in the developing solution after development, and the precipitated photoinitiator may reattach to a board | substrate, and a display element may become bad, or the developing tank of a developing apparatus, or The problem may arise that a photoinitiator precipitates in a developing nozzle, and this causes a developing fault. The problem of precipitation of a photoinitiator is more serious with the recent increase of the size of a board | substrate, ie, the increase of the unexposed area area.

Therefore, the problem of the present invention is to faithfully reproduce the design size of the mask pattern at high sensitivity, to have excellent adhesion with the substrate, to achieve sufficient spacer shape and film thickness at an exposure dose of 1500 J / m 2 or less, and to photopolymerize in the developer solution. A radiation-sensitive resin composition capable of forming a spacer for a liquid crystal display device having excellent strength and heat resistance as well as solving an initiator precipitation problem, a pattern forming process suitable for the radiation-sensitive resin composition, a spacer formed thereby and the spacer formed It is providing a liquid crystal display element.

According to the present invention, the problem is firstly

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

[B] a polymerizable compound having an ethylenically unsaturated bond and

[C] photopolymerization initiator

When the content of the [C] photopolymerization initiator is 0.1 to 5 parts by weight based on 100 parts by weight of the [B], the radiation-sensitive resin composition (hereinafter referred to as "radiation-sensitive resin composition (A)" Is achieved).

Second, the present invention

(1) forming a coating film of the radiation-sensitive composition on the substrate;

(2) irradiating at least a portion of said coating film under low oxygen conditions,

(3) developing process and

(4) heating process

It includes a spacer forming method characterized in that it comprises in order.

Third, the present invention includes a spacer forming method (hereinafter sometimes referred to as "step (a)"), wherein the low oxygen condition is an inert gas atmosphere.

Fourthly, the present invention includes a spacer forming method (hereinafter sometimes referred to as "step (b)"), wherein the low oxygen condition is under reduced pressure.

Fifth, the present invention includes a method for forming a spacer (hereinafter sometimes referred to as "step (c)"), wherein the low oxygen condition is a condition in which the surrounding atmosphere is blocked by a cover film.

Sixthly, the present invention includes a spacer formed by the above method.

Seventh, the present invention includes a liquid crystal display device having the spacer.

Hereinafter, the present invention will be described in detail.

Radiation-sensitive resin composition (A)

Copolymer [A]

[A] component in a radiation sensitive resin composition (A) is (a1) ethylenically unsaturated carboxylic acid and / or ethylenically unsaturated carboxylic anhydride, (a2) epoxy group containing ethylenically unsaturated compound, and (a3) Copolymers of other ethylenically unsaturated compounds (hereinafter sometimes referred to as "copolymer [A]").

(A1) ethylenically unsaturated carboxylic acid and / or ethylenically unsaturated carboxylic anhydride (hereinafter, referred to collectively as "unsaturated carboxylic acid monomer (a1)") in each component constituting the copolymer [A] Examples include monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, 2-methacryloyloxyethyl succinic acid and 2-methacryloyloxyethyl hexahydrophthalic acid; Dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, mesaconic acid and itaconic acid; Anhydrides of the said dicarboxylic acid, etc. are mentioned.

Among these unsaturated carboxylic acid monomers (a1), acrylic acid, methacrylic acid, maleic anhydride, and the like are preferred from the viewpoints of copolymerization reactivity, solubility in an aqueous alkali solution, and ease of acquisition.

In a radiation sensitive resin composition (a), an unsaturated carboxylic acid monomer (a1) may be used independently, or may mix and use 2 or more types.

The content of the repeating unit derived from the unsaturated carboxylic acid monomer (a1) in the copolymer [A] is preferably 5 to 50% by weight, more preferably 10 to 40% by weight, particularly preferably 15 to 30% by weight. %to be. In this case, when the content 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 decrease, and when it exceeds 40% by weight, the solubility in the aqueous alkali solution becomes too large. There is concern.

Examples of the (a2) epoxy group-containing ethylenically unsaturated compound (hereinafter sometimes referred to as "epoxy group-containing monomer (a2)") include glycidyl acrylate, 2-methylglycidyl acrylate, and 3,4-epoxy acrylate. Acrylic acid epoxy alkyl esters such as butyl, acrylic acid 6,7-epoxyheptyl and acrylic acid 3,4-epoxycyclohexyl; Meta, such as glycidyl methacrylate, 2-methylglycidyl methacrylate, 3,4-epoxybutyl methacrylate, 6,7-epoxyheptyl methacrylate, and 3,4-epoxycyclohexyl methacrylate Krylic acid epoxy alkyl esters; α-alkyl acrylate epoxy alkyl esters such as α-ethyl acrylate glycidyl, α-n-propyl acrylate glycidyl, α-n-butyl acrylate glycidyl and α-ethyl acrylate 6,7-epoxyheptyl; and glycidyl ethers such as o-vinyl benzyl glycidyl ether, m-vinyl benzyl glycidyl ether and p-vinyl benzyl glycidyl ether.

Among these epoxy group-containing monomers (a2), in view of copolymerization reactivity and the strength of the spacer, methacrylate glycidyl, methacrylic acid 2-methylglycidyl, methacrylic acid 6,7-epoxyheptyl, o-vinylbenzyl glycine Dyl ether, m-vinyl benzyl glycidyl ether, p-vinyl benzyl glycidyl ether, etc. are preferable.

In a radiation sensitive resin composition (a), an epoxy group containing monomer (a2) may be used independently, or may mix and use 2 or more types.

The content rate of the repeating unit derived from an epoxy group containing monomer (a2) in copolymer [A] becomes like this. Preferably it is 10-70 weight%, More preferably, it is 20-60 weight%, Especially preferably, it is 30-50 weight%. In this case, when the content rate of the repeating unit derived from an epoxy group containing monomer (a2) is less than 10 weight%, the intensity | strength of the spacer obtained tends to fall, and when it exceeds 70 weight%, the storage stability of the copolymer obtained will fall. There is a tendency.

Examples of (a3) other ethylenically unsaturated compounds (hereinafter sometimes referred to simply as "other monomers (a3)") include alkyl acrylates such as methyl acrylate and i-propyl acrylate; Methacrylic acid alkyl esters such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, and t-butyl methacrylate; 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 Acrylic alicyclic esters such as isoboroyl acrylate; Cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, tricyclo methacrylate [5.2.1.0 ^2,6 ] decane-8-yl, 2- (tricyclo [5.2.1.0 ^2,6 ] methacrylate Methacrylic acid alicyclic esters such as decan-8-yloxy) ethyl and isobornyl methacrylate; Aryl esters or aralkyl esters of acrylic acid such as phenyl acrylate and benzyl acrylate; Aryl esters or aralkyl esters of methacrylic acid, such as phenyl methacrylate and benzyl methacrylate; Dicarboxylic acid dialkyl esters such as diethyl maleate, diethyl fumarate and diethyl itaconic acid; Methacrylic acid hydroxyalkyl esters such as 2-hydroxyethyl methacrylic acid and 2-hydroxypropyl methacrylic acid; Unsaturated hetero five-membered and six-membered methacrylic acid esters containing one atom of oxygen such as tetrahydrofurfuryl methacrylate, tetrahydrofuryl methacrylate, tetrahydropyran-2-methylmethacrylate, and the like; Vinyl aromatic compounds such as styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, and p-methoxystyrene; Acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, vinyl chloride, vinylidene chloride, as well as conjugated diene-based compounds such as 1,3-butadiene, isoprene and 2,3-dimethyl-1,3-butadiene Vinyl acetate etc. are mentioned.

Among these other monomers (a3), 2-methylcyclohexyl acrylate, t-butyl methacrylate and tricyclo methacrylate [5.2.1.0 ^2,6 ] from the viewpoint of copolymerization reactivity and solubility of the obtained copolymer in aqueous alkali solution. Decan-8-yl, styrene, p-methoxystyrene, tetrahydrofurfuryl methacrylate, 1,3-butadiene and the like are preferred.

In the radiation-sensitive resin composition (A), the other monomers (a3) may be used alone or in combination of two or more thereof.

The content of the repeating unit derived from the other monomer (a3) in the copolymer [A] is preferably 10 to 70% by weight, more preferably 20 to 50% by weight, particularly preferably 30 to 50% by weight. In this case, when the content rate of the repeating unit derived from other monomers (a3) is less than 10 weight%, the storage stability of the copolymer obtained tends to fall, and when it exceeds 70 weight% with respect to the aqueous alkali solution of the copolymer obtained Solubility tends to be lowered.

Copolymer [A] has a carboxyl group and / or a carboxylic anhydride group and an epoxy group, has suitable solubility in aqueous alkali solution, and can be easily cured by heating without using a special curing agent. The radiation-sensitive resin composition (a) having (a) can easily form a spacer of a predetermined pattern in which developing residues do not occur during development and the film does not wear out.

Copolymer [A] can be produced, for example, by polymerizing an unsaturated carboxylic acid monomer (a1), an epoxy group-containing monomer (a2) and other monomers (a3) in the presence of a radical polymerization initiator in a suitable solvent.

Examples of the solvent used for the polymerization include alcohols, ethers, glycol ethers, ethylene glycol alkyl ether acetates, diethylene glycol, propylene glycol monoalkyl ethers, propylene glycol alkyl ether acetates, propylene glycol alkyl ether propionates, aromatic hydrocarbons, ketones And esters.

Specific examples of each of these include:

Examples of the alcohols include methanol, ethanol, benzyl alcohol, 2-phenylethyl alcohol, 3-phenyl-1-propanol, and the like;

Examples of the ethers include tetrahydrofuran and the like;

Examples of the glycol ethers include ethylene glycol monomethyl ether and ethylene glycol monoethyl ether;

Examples of ethylene glycol alkyl ether acetates include methyl cellosolve acetate, ethyl cellosolve acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monoethyl ether acetate, and the like;

Examples of diethylene glycol include diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, and the like;

Examples of propylene glycol monoalkyl ethers include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether and the like;

Examples of propylene glycol alkyl ether propionate include propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol butyl ether acetate, and the like;

Examples of propylene glycol alkyl ether acetates include propylene glycol methyl ether propionate, propylene glycol ethyl ether propionate, propylene glycol propyl ether propionate, propylene glycol butyl ether propionate and the like;

Examples of aromatic hydrocarbons include toluene, xylene and the like;

Examples of ketones include methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, and the like;

Examples of the ester include methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, methyl hydroxyacetate, Ethyl hydroxyacetate, butyl hydroxyacetate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, propyl 3-hydroxypropionate, butyl hydroxypropionate, 2-hydroxy-3-methyl butyrate, methyl methoxyacetate, ethyl methoxyacetate, methoxyacetic acid propyl, butyl acetate, methyl ethoxyacetate, ethoxyacetic acid, ethoxyacetic acid propyl, ethoxyacetic acid Butyl, methyl propoxy acetate, ethyl propoxy acetate, propyl propoxy acetate, butyl propoxy acetate, methyl butoxy acetate, butoxide Ethyl acetate, propyl butoxy acetate, butyl butoxy 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, 3 Methyl methoxypropionate, 3-methoxy ethylpropionate, 3-methoxy propylpropionate, 3-methoxy butyl propionate, 3-ethoxy propylpropionate, 3-ethoxy propylpropionate, 3-ethoxy propylpropionate, 3- Butyl ethoxypropionate, methyl 3-propoxypropionate, ethyl 3-propoxypropionate, propyl 3-propoxypropionate, butyl 3-propoxypropionate, methyl 3-butoxypropionate, ethyl 3-butoxypropionate, 3- Esters such as butyl butoxypropionate and butyl 3-butoxypropionate.

Among these, ethylene glycol alkyl ether acetate, diethylene glycol, propylene glycol monoalkyl ether and propylene glycol alkyl ether acetate are preferable, and especially diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, propylene glycol methyl ether, and propylene glycol methyl ether Acetate is particularly preferred.

The solvents may be used alone or in combination of two or more thereof.

In addition, the radical polymerization initiator used for the said polymerization is not specifically limited, For example, 2,2'- azobisisobutyronitrile, 2,2'- azobis- (2, 4- dimethylvaleronitrile) , 2,2'-azobis- (4-methoxy-2,4-dimethylvaleronitrile), 4,4'-azobis (4-cyanovaleric acid), dimethyl 2,2'-azobis ( Azo compounds such as 2-methylpropionate) and 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile); Organic peroxides such as benzoyl peroxide, lauroyl peroxide, t-butylperoxy pivalate and 1,1-bis (t-butylperoxy) cyclohexane; Hydrogen peroxide and the like. In addition, when using a peroxide as a radical polymerization initiator, it can also be used together with a reducing agent as a redox type initiator.

These radical polymerization initiators may be used independently, or may mix and use 2 or more types.

The copolymer [A] thus obtained may be used as it is for the production of a radiation sensitive resin composition, or may be separated from the solution and used for the production of a radiation sensitive resin composition.

The polystyrene reduced weight average molecular weight (hereinafter referred to as "Mw") by gel permeation chromatography (GPC) of the copolymer [A] is generally 2,000 to 100,000, preferably 5,000 to 50,000. In this case, when Mw is less than 2,000, developability, residual film ratio, etc. of the resulting film may be lowered, or pattern shape, heat resistance, etc. may be impaired, and when it exceeds 100,000, resolution may be lowered or pattern shape may be damaged.

Polymeric compounds [B]

[B] component in a radiation sensitive resin composition (a) contains the polymeric compound which has an ethylenically unsaturated bond (henceforth a "polymerizable compound [B]").

Although polymeric compound [B] is not specifically limited, Monofunctional, bifunctional, or trifunctional or more than (meth) acrylic acid ester is preferable from a viewpoint of the high polymerizability and the strength of the spacer obtained.

Examples of the monofunctional (meth) acrylic acid esters include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, diethylene glycol monoethyl ether acrylate, diethylene glycol monoethyl ether methacrylate, isobo Ronyl acrylate, isoboroyl methacrylate, 3-methoxybutyl acrylate, 3-methoxybutyl methacrylate, 2-acryloyloxyethyl-2-hydroxypropyl phthalate, 2-methacrylo Iloxyethyl-2-hydroxypropyl phthalate etc. are mentioned, Examples of a commercial item are Aronix M-101, Copper M-111, Copper M-114 (made by Toa Kosei Co., Ltd.); KAYARAD TC-110S, Copper TC-120S (manufactured by Nippon Kayaku Co., Ltd.); Biscot 158, East 2311 (The Osaka Yuki Kagaku Kogyo KK) etc. are mentioned.

Examples of the difunctional (meth) acrylic acid esters include ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, tetraethylene glycol diacrylate, Tetraethylene glycol dimethacrylate, 1,6-hexanedioldiacrylate, 1,6-hexanedioldimethacrylate, 1,9-nonanedioldiacrylate, 1,9-nonanedioldimethacrylate, Bisphenoxy ethanol fluorene diacrylate, bisphenoxy ethanol fluorene dimethacrylate, etc. are mentioned, Examples of a commercial item are Aronix M-210, M-240, M-6200 (Dagogo Ossei Co., Ltd., KAYARAD HDDA, East HX-220, East R-604 (made by Nippon Kayaku Co., Ltd.), Biscot 260, East 312, East 335 HP (Osaka Yuuki Kagaku Kogyo Co., Ltd.) ), And the like.

In addition, examples of the trifunctional or higher (meth) acrylic acid esters include trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, and pentaerythritol tetraacrylic acid. Late, pentaerythritol tetramethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, tri (2-acrylo) Monooxyethyl) phosphate, tri (2-methacryloyloxyethyl) phosphate, and the like.

In particular, as a 9- or more (meth) acrylate, the trifunctional, tetrafunctional, and 5-functional (meth) which has an alkylene linear and alicyclic structure, and contains a compound containing two or more isocyanate groups, and contains one or more hydroxyl groups in a molecule | numerator The urethane acrylate compound obtained by making an acrylate compound react is mentioned.

Examples of the commercially available products include Aronix M-309, M-400, M-405, M-450, M-7100, M-8030, M-8060, TO-1450 (Doa Kosei ( Co.Ltd), KAYARAD TMPTA, DONG DPHA, DONG DPCA-20, DONG DPCA-30, DONG DPCA-60, DONG DPCA-120 (product of Nippon Kayaku Co., Ltd.), BISCOORT 295, DONG 300, DONG 360, Copper GPT, copper 3PA, copper 400 (manufactured by Osaka Yuki Kagaku Kogyo Co., Ltd.). Examples of commercially available products of 9 or more polyfunctional urethane acrylates include New Frontier R-1150 (above, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and KAYARAD DPHA-40H (above, manufactured by Nippon Kayaku Co., Ltd.). Can be.

Among these monofunctional, bifunctional or trifunctional or higher (meth) acrylic acid esters, trifunctional or higher (meth) acrylic acid esters are more preferable, and trimethylolpropane triacrylate, pentaerythritol triacrylate and pentaerythritol tetra Acrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate are preferred.

The said monofunctional, bifunctional or trifunctional or more (meth) acrylic acid ester may be used individually, or may mix and use 2 or more types.

The usage-amount of the polymeric compound [B] in a radiation sensitive resin composition (A) becomes like this. Preferably it is 50-140 weight part, More preferably, it is 60-120 weight part with respect to 100 weight part of copolymers [A]. In this case, if the amount of the polymerizable compound [B] is less than 50 parts by weight, there is a fear that development residues occur during development, and if it exceeds 140 parts by weight, the hardness of the spacer obtained tends to be lowered.

Photoinitiator [C]

The photoinitiator as used in this invention means the component which generate | occur | produces the active species which can start superposition | polymerization of polymeric compound [B] by exposure by visible light, an ultraviolet-ray, an ultraviolet-ray, a charged particle beam, X-rays, etc. [C] component in the photosensitive resin composition (A) does not micro-associate in order to provide a high quantum yield in a composition coating film, and it is preferable that there is little optical energy loss by the self-quenching effect. For this reason, it is preferable that the component [C] in the photosensitive resin composition (A) is uniformly dispersed. In order to uniformly disperse the photosensitive resin composition (A) composed of an organic material, it has a solubility parameter almost equal to that of the composition. It is preferable to exist, and it is preferable that [C] alone has hydrophobicity to the extent that it does not melt | dissolve in an alkaline developing solution.

The amount of the photopolymerization initiator [C] used in the radiation-sensitive resin composition (A) is 0.1 to 5 parts by weight, preferably 0.2 to 3 parts by weight, more preferably 0.2 to 1.5 parts by weight based on the polymerizable compound [B]. to be. When it exceeds 5 parts by weight, the radically active species generated by [C] become inactivated by the radically generated radicals that are excessively generated, which may prevent the smooth progress of photopolymerization of the polymerizable compound [B]. In addition, there is a tendency that [C] is easy to micro-associate, and that light energy cannot be effectively used by magnetic quenching, or that [C] is easily precipitated in a developer. On the other hand, when it is less than 0.1 weight part, heat resistance, surface hardness, or chemical resistance tends to fall.

Photoinitiator [C] may be used independently, or may mix and use 2 or more types.

By using the radiation-sensitive resin composition (A) in the steps (a), (b) and (c), radical species generated from the photopolymerization initiator [C] can be effectively used, and at an exposure dose of 1500 J / m 2 or less. It is also possible to obtain spacers having sufficient sensitivity and adhesion.

Specific examples of such a compound [C] include biimidazole compounds, benzoin compounds, acetophenone compounds, benzophenone compounds, α-diketone compounds, polynuclear quinone compounds, xanthone compounds, phosphine compounds, and triazine compounds. A compound, an oxime compound, etc. are mentioned.

Oxime compounds include 1- [9-ethyl-6-benzoyl-9.H.-carbazol-3-yl] -nonane-1,2-nonane-2-oxime-O-benzoate, 1- [9- Ethyl-6-benzoyl-9.H.-carbazol-3-yl] -nonan-1,2-nonan-2-oxime-O-acetate, 1- [9-ethyl-6-benzoyl-9.H. -Carbazol-3-yl] -pentane-1,2-pentane-2-oxime-O-acetate, 1- [9-ethyl-6-benzoyl-9.H.-carbazol-3-yl] -octane -1-onoxime-O-acetate, 1- [9-ethyl-6- (2-methylbenzoyl) -9.H.-carbazol-3-yl] -ethane-1-onoxime-O-benzoate , 1- [9-ethyl-6- (2-methylbenzoyl) -9.H.-carbazol-3-yl] -ethane-1-onoxime-O-acetate, 1- [9-ethyl-6- (1,3,5-trimethylbenzoyl) -9.H.-carbazol-3-yl] -ethane-1-onoxime-O-benzoate, 1- [9-butyl-6- (2-ethylbenzoyl ) -9.H.-carbazol-3-yl] -ethane-1-onoxime-O-benzoate, 1,2-octadione-1- [4- (phenylthio) phenyl] -2- (O -Benzoyloxime), 1,2-butanedione-1- [4- (phenylthio) phenyl] -2- (O-benzoyloxime), 1,2-butanedione-1- [4- (phenylthio) phenyl ] -2- (O-acetyloxime), 1,2- Tadion-1- [4- (methylthio) phenyl] -2- (O-benzoyloxime), 1,2-octadione-1- [4- (phenylthio) phenyl] -2- (O- (4 -Methylbenzoyl oxime)) etc. are mentioned. Among these, 1,2-octadione-1- [4- (phenylthio) phenyl] -2- (O-benzoyloxime) is particularly preferable. Among these, 1- [9-ethyl-6- (2-methylbenzoyl) -9.H.-carbazol-3-yl] -ethane-1-one oxime-O-acetate is particularly preferable.

Examples of the acetophenone compounds include α-hydroxyketone compounds, α-aminoketone compounds, and compounds other than these.

Specific examples of the α-hydroxyketone compound include 1-phenyl-2-hydroxy-2-methylpropan-1-one and 1- (4-i-propylphenyl) -2-hydroxy-2-methylpropane -1-one, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexylphenyl ketone, and the like. The α-aminoketone compounds Specific examples of 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -Butanone-1, etc., Specific examples of compounds other than these include 2,2-dimethoxyacetophenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, and the like. Can be mentioned.

Specific examples of the biimidazole-based compound

2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetrakis (4-ethoxycarbonylphenyl) -1,2'-biimidazole,

2,2'-bis (2-bromophenyl) -4,4 ', 5,5'-tetrakis (4-ethoxycarbonylphenyl) -1,2'-biimidazole,

2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole,

Bis (2,4-dichlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole,

2,2'-bis (2,4,6-trichlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole,

2,2'-bis (2-bromophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole,

Bis (2,4-dibromophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole,

2,2'-bis (2,4,6-tribromophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole

And the like.

2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis (2) in the said biimidazole type compound , 4-dichlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis (2,4,6-trichlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole and the like are preferred, and particularly preferred is 2,2'-bis (2,4-dichlorophenyl) -4,4', 5,5 ' -Tetraphenyl-1,2'-biimidazole.

In order to increase or decrease the biimidazole compound, an aliphatic or aromatic compound having a dialkylamino group (hereinafter sometimes referred to as "sensitizer [D]") can be used.

Specific examples of the sensitizer [D] include N-methyldiethanolamine, 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis (diethylamino) benzophenone and ethyl p-dimethylaminobenzoate and p-dimethylaminobenzoic acid i-amyl and the like. Of these sensitizers, 4,4'-bis (diethylamino) benzophenone is preferred.

These sensitizers [D] can also use 2 or more types simultaneously.

The amount of the sensitizer [D] to be used is preferably 0.1 to 50 parts by weight, more preferably 1 to 20 parts by weight with respect to 100 parts by weight of [A].

When the amount of the compound [D] is less than 0.1 part by weight, the spacer film obtained tends to be worn or a pattern shape defect occurs, and when it exceeds 50 parts by weight, a pattern shape defect also tends to occur.

In the case of using a biimidazole compound, a thiol compound (hereinafter sometimes referred to as "thiol compound [D-2]") can be further used as a hydrogen donor compound. The biimidazole compound is sensitized by a benzophenone-based compound having a dialkylamino group, and the biimidazole compound cleaves to generate an imidazole radical. In this case, a high radical polymerization initiation ability is not exhibited, and in many cases, it becomes an undesirable shape, such as an inverse taper shape (one side of a film surface is longer than an edge of a board | substrate side, an inverted triangle shape in cross-sectional shape). . This problem is alleviated by adding thiol-based compound [D-2] to the system in which the biimidazole compound and the benzophenone-based compound having a dialkylamino group coexist. The donation of hydrogen radicals from thiol compounds to the imidazole radicals results in compounds having neutral imidazoles and sulfur radicals having high polymerization initiation capability. This makes the forward taper shape more preferable than the reverse taper shape.

The use ratio of the thiol-based compound [D-2] is preferably 0.1 to 50 parts by weight, more preferably 1 to 20 parts by weight with respect to 100 parts by weight of the compound [C]. When the amount of the thiol-based compound [D-2] is less than 0.1 part by weight, the spacer film obtained tends to be worn or a pattern shape defect occurs, and when it exceeds 50 parts by weight, a pattern shape defect also tends to occur.

Specific examples thereof include 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 2-mercaptobenzoimidazole, 2-mercapto-5-methoxybenzothiazole, 2-mercapto-5-methoxy And aliphatic monothiols such as aromatic thiols such as benzoimidazole, 3-mercaptopropionic acid, 3-mercaptopropionate methyl, 3-mercaptopropionate ethyl, and 3-mercaptopropionate octyl. Examples of the bifunctional or higher aliphatic thiol include 3,6-dioxa-1,8-octanedithiol, pentaerythritol tetra (mercaptoacetate), pentaerythritol tetra (3-mercaptopropionate), and the like. .

additive

Additives other than the said component can be mix | blended with a radiation sensitive resin composition (A) as needed within the range which does not impair the desired effect of this invention.

For example, surfactants may be blended to improve applicability. As said surfactant, a fluorine-type surfactant and a silicone type surfactant can be used preferably.

As the fluorine-based surfactant, a compound having a fluoroalkyl or a fluoroalkylene group in at least one of terminal, main chain and side chain can be preferably used. Specific examples thereof include 1,1,2,2-tetrafluoro Octyl (1,1,2,2-tetrafluoropropyl) ether, 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 di ( 1,1,2,2,3,3-hexafluoropentyl) ether, sodium perfluorododecylsulfonate, 1,1,2,2,8,8,9,9,10,10-decafluoro Rhododecane, 1,1,2,2,3,3-hexafluorodecane, sodium fluoroalkylbenzenesulfonate, sodium fluoroalkylphosphonate, sodium fluoroalkyl carboxylate, fluoroalkylpolyoxyethylene ether,Diglycerin tetrakis (fluoroalkyl polyoxyethylene ether), fluoroalkyl ammonium iodide, fluoroalkyl betaine, fluoroalkyl polyoxyethylene ether, perfluoroalkyl polyoxyethanol, perfluoroalkyl alkoxyl And fluorine-based alkyl esters.

In addition, examples of these commercial items include BM-1000, BM-1100 (above, manufactured by BM CHEMIE Co., Ltd.), Megapack F142D, East F172, East F173, East F183, East F178, East F191, East F471, East F476 (above, Dainippon Ink Chemical Industries, Ltd.), Florard FC-170C, FC-171, FC-430, FC-431 (above, Sumitomo 3M Corporation), Suplon S-112, East S-113 , S-131, S-141, S-145, S-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-106 (Above, Asahi Glass Co., Ltd.), F-Top EF301, East 303, East 352 (above, New Care Kasei Co., Ltd.), Butagent FT-100, East FT-110, East FT-140A, East FT -150, East FT-250, East FT-251, East FTX-251, East FTX-218, East FT-300, East FT-310, East FT-400S (above, Neos Co., Ltd.) have.

Examples of silicone surfactants include 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, DC-57, DC-190 (above, Toray Dow Corning Silicon Co., Ltd.), TSF-4440, TSF-4300, TSF-4445, TSF-4446, TSF-4460, TSF-4452 (above, What is marketed by brand names, such as GE Toshiba Silicone Co., Ltd., are mentioned.

Moreover, as an example of surfactant other than the above-mentioned, 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, are mentioned, As a commercial item, KP341 (made by Shin-Etsu Chemical Co., Ltd.) , Polyflow no. 57, No. 95 (manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd.).

These surfactants may be used alone or in combination of two or more thereof.

The blending amount of the surfactant 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 compounding quantity of surfactant exceeds 5 weight part, there exists a tendency for film | membrane roughness to arise easily at the time of application | coating.

Moreover, in order to further improve adhesiveness with a board | substrate, an adhesion | attachment adjuvant can be mix | blended.

As said adhesion | attachment adjuvant, a functional silane coupling agent is preferable, The silane coupling agent which has reactive functional groups, such as a carboxyl group, a methacryloyl group, an isocyanate group, an epoxy group, is mentioned, More specifically, a trimethoxysilyl Benzoic acid, γ-methacryloyloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatepropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, 2- ( 3, 4- epoxycyclohexyl) ethyl trimethoxysilane etc. are mentioned.

These adhesion aids may be used independently, or may mix and use 2 or more types.

The compounding quantity of an adhesion | attachment adjuvant becomes like this. Preferably it is 20 weight part or less, More preferably, it is 10 weight part or less with respect to 100 weight part of copolymers [A]. In this case, when the compounding quantity of an adhesion | attachment adjuvant exceeds 20 weight part, there exists a tendency for developing residue to become easy to generate | occur | produce.

Other additives can be added, and these are added for the purpose of improving storage stability and the like. Specifically, sulfur, quinones, hydroquinones, polyoxy compounds, amines, nitroso compounds are mentioned. Examples thereof include 4-methoxyphenol, N-nitroso-N-phenylhydroxylamine aluminum, and the like. These are preferably used in an amount of 3.0 parts by weight or less, more preferably 0.001 to 0.5 parts by weight with respect to 100 parts by weight of the copolymer [A]. When it exceeds 3.0 weight part, sufficient sensitivity is not achieved and a pattern shape deteriorates.

In addition, a compound having an N- (alkoxymethyl) glycoluril compound, an N- (alkoxymethyl) melamine compound, and a bifunctional or higher epoxy group in one molecule can be added for improving heat resistance. Specific 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-tetra (i-propoxymethyl) glycoluril, N, N, N, N-tetra (n-butoxy Methyl) glycoluril, N, N, N, N-tetra (t-butoxymethyl) glycoluril, and the like. Among these, especially N, N, N, N- tetra (methoxymethyl) glycoluril is preferable. Specific examples of the 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 (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, N, N, N, N, N-hexa (methoxymethyl) melamine is particularly preferable. As these commercial items, Nikarak N-2702, MW-30M (above, Sanwa Chemical Co., Ltd.), etc. are mentioned.

Examples of the compound having a bifunctional or higher functional epoxy group in one molecule include ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, and tripropylene glycol digly Cidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, trimethylol propane triglycidyl ether, hydrogen Addition bisphenol A diglycidyl ether, bisphenol A diglycidyl ether, etc. are mentioned. Specific examples of these commercial items include epolite 40E, epolite 100E, epolite 200E, epolite 70P, epolite 200P, epolite 400P, epolite 40E, epolite 1500NP, epolite 1600, epolite 80MF, epolite 100MF, Epolite 4000, epolite 3,002 (above Kyoeisha Chemical Co., Ltd. product) etc. are mentioned. These may be used independently, or may mix and use 2 or more types.

Composition solution

A radiation sensitive resin composition (A) is manufactured as a composition solution which melt | dissolved structural components, such as a copolymer [A], a polymeric compound [B], and a photoinitiator [C], in the appropriate solvent at the time of its use generally.

As a solvent used in the preparation of the composition solution, those components constituting the radiation-sensitive resin composition (A) are uniformly dissolved and do not react with each component. Examples thereof include polymerization to produce a copolymer [A]; The same thing as the solvent illustrated with respect to this is mentioned.

Among these solvents, for example, alcohols, glycol ethers, ethylene glycol alkyl ether acetates, esters, and diethylene glycol are preferably used from the viewpoints of solubility of each component, reactivity with each component, and ease of coating film formation. Among these, for example, benzyl alcohol, 2-phenylethyl alcohol, 3-phenyl-1-propanol, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether It may be particularly preferable to use diethylene glycol dimethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl methoxy propionate and ethyl ethoxypropionate.

Moreover, in order to improve the in-plane uniformity of a film thickness, you may use a high boiling point solvent together with the said solvent. Examples of the high boiling point solvent that can be used together include N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, and N-methylpyrrolidone , Dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether, acetonyl acetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl acetate, ethyl benzoate, diethyl oxalate, maleic acid Ethyl, (gamma) -butyrolactone, ethylene carbonate, a propylene carbonate, a phenyl cellosolve acetate, etc. are mentioned. Among them, N-methylpyrrolidone, γ-butyrolactone, and N, N-dimethylacetamide are preferable.

When using a high boiling point solvent together as a solvent of the radiation sensitive resin composition of this invention, the usage-amount is preferably 50 weight% or less, More preferably, it is 40 weight% or less, More preferably, it is 30 weight with respect to a solvent whole quantity. It can be made% or less. When the usage-amount of a high boiling point solvent exceeds the above-mentioned usage-amount, the film thickness uniformity, a sensitivity, and a residual film ratio of a coating film may fall.

When manufacturing the radiation sensitive resin composition of this invention in solution state, the total amount of components other than a solvent, ie, the copolymer [A], [B] component and [C] component, and the other components added arbitrarily in a solution The proportion to be occupied can be arbitrarily set according to the purpose of use or the value of the desired film thickness and the like, for example, 5 to 50% by weight, preferably 10 to 40% by weight, more preferably 15 to 35% by weight.

The composition solution thus prepared may be used after being filtered using a Millipore filter having a pore diameter of about 0.5 μm or the like.

The radiation sensitive resin composition (A) is particularly suitable as a material for forming a spacer used for a liquid crystal display element or a touch panel.

Spacer Formation Method

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

The spacer forming method of the present invention,

(1) forming a coating film of the radiation sensitive composition of the present invention on a substrate;

(2) irradiating at least a part of the coating film with radiation;

(3) developing process and

(4) heating process

It characterized in that it comprises in order.

Hereinafter, these processes are demonstrated in order.

(1) Process of forming the coating film of the radiation sensitive composition of this invention on a board | substrate

When forming the spacer for display panel using the photosensitive resin composition (A), after apply | coating a composition solution to the surface of a board | substrate or a film, it pre-fires, removes a solvent, and forms a coating film or apply | coats once on a board | substrate or a film Is used to transfer the formed coating film onto a separate substrate or film.

The coating method of a composition solution is not specifically limited, For example, the spraying method, the roll coating method, the spin coating method (spin coating method), the slit die coating method, the bar coating method, the inkjet coating method, etc. can be used, In particular, the spin coating method and the slit die coating method are preferable.

In addition, the conditions of prefiring vary depending on the type of each component, the mixing ratio, and the like, and are generally about 1 to 15 minutes at 70 ° C to 120 ° C.

(2) irradiating at least a part of the coating film with radiation

Subsequently, at least part of the formed film is exposed to radiation. In this case, when exposing to a part of film, it exposes through the photomask which has a predetermined pattern.

As the radiation used for exposure, visible rays, ultraviolet rays, far ultraviolet rays, and the like can be used, but radiation having a wavelength in the range of 190 to 450 nm is preferable, and particularly radiation containing 365 nm ultraviolet rays is preferable.

It is preferable that the said exposure process is performed under low oxygen conditions, For example, the surrounding atmosphere is formed by the process (a) of exposing under inert gas atmosphere, and forming a pattern, the process of exposing under vacuum (b), or a cover film. The step (c) of performing exposure in the blocked state and forming a pattern is preferably applied.

As a cover film layer which blocks the ambient atmosphere, a film layer that efficiently transmits the exposure and does not lose light energy is preferable, and an organic film or an inorganic film is used. The cover film layer is removed before development after exposure or dissolved in a developer upon development. When melt | dissolving and removing at the time of image development, it is necessary to be an organic composition which shows water solubility or alkali solubility.

(3) developing process

Next, by developing the film after exposure, the predetermined pattern from which the unnecessary part was removed is formed.

Examples of the developer used for development include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate and 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 appropriate amount of a water-soluble organic solvent such as methanol or ethanol and / or a surfactant may be added to the aqueous solution of the alkaline compound.

As a developing method, arbitrary methods, such as a paddle method, an immersion method, a shower method, etc. can be used, and developing time is generally about 10 second-180 second at normal temperature.

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

(4) heating process

Subsequently, the obtained pattern is subjected to a predetermined time at a predetermined temperature, for example, 150 ° C to 250 ° C by a heating device such as a hot plate, an oven, for example, 5 minutes to 30 minutes on an hot plate, in an oven. The desired spacer can be obtained by heating (post-baking) for 30 to 180 minutes.

Here, when the composition of the preferable radiation sensitive resin composition (A) is illustrated more concretely, it is as following (i)-(iv):

(i) As the component constituting the copolymer [A], the unsaturated carboxylic acid monomer (a1) contains a single or a mixture of two or more kinds of acrylic acid, methacrylic acid and maleic anhydride groups, and the epoxy group-containing monomer (a2) Single or two or more of the group of glycidyl methacrylate, 6,7-epoxyheptyl methacrylate, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether and p-vinylbenzyl glycidyl ether Mixtures, and other monomers (a3) are 2-methylcyclohexyl acrylate, t-butyl methacrylate, tricyclo methacrylate [5.2.1.0 ^2,6 ] decane-8-yl, styrene, p-methoxy Compositions comprising sole or a mixture of two or more of styrene, tetrahydrofurfuryl methacrylate and 1,3-butadiene groups;

(ii) In the above (i), the content of the repeating unit derived from the unsaturated carboxylic acid monomer (a1) in the copolymer [A] is 5 to 40% by weight, more preferably 10 to 30% by weight, and an epoxy group The content rate of the repeating unit derived from a containing monomer (a2) is 10 to 70 weight%, More preferably, it is 20 to 60 weight%, and the content rate of the repeating unit derived from other monomer (a3) is 10 to 70 weight%, Further Preferably 20 to 50% by weight of the composition;

(iii) In the above (i) or (ii), the polymerizable compound [B] is a monofunctional, difunctional or trifunctional or higher (meth) acrylic acid ester, particularly preferably trifunctional or higher (meth) acrylic acid ester Composition;

(iv) In any one of (i)-(iii), the usage-amount of a polymeric compound [B] is 50-140 weight part with respect to 100 weight part of copolymers [A], More preferably, it is 60-120 weight And the amount of the photopolymerization initiator [C] is 0.5 to 5 parts by weight, more preferably 0.5 to 3 parts by weight based on 100 parts by weight of the polymerizable compound [B].

Example

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, but the present invention is not limited to these Examples.

&Lt; Synthesis Example 1 &

5 parts by weight of 2,2'-azobis (2,4-dimethylvaleronitrile), 200 parts by weight of diethylene glycol methylethyl ether, and 18 parts by weight of methacrylic acid were added to a flask equipped with a cooling tube and a stirrer. 40 parts by weight of acid glycidyl, 5 parts by weight of styrene, and 32 parts by weight of tricyclo [5.2.1.0 ^2,6 ] decane-8-yl methacrylate were substituted for nitrogen, and then 5 parts by weight of 1,3-butadiene. The temperature of the solution was raised to 70 DEG C while stirring and slowly stirring, and polymerization was carried out while maintaining the temperature for 5 hours to obtain a solution of copolymer [A-1].

Solid content concentration of the said solution was 33.0 weight%, and Mw of copolymer [A-1] was 11,000.

&Lt; 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), 200 parts by weight of diethylene glycol methylethyl ether, 18 parts by weight of methacrylic acid, and methacrylic 20 parts by weight of acid glycidyl, 5 parts by weight of styrene, 32 parts by weight of tricyclo [5.2.1.0 ^2,6 ] decane-8-yl, 25 parts by weight of tetrahydrofurfuryl methacrylate were substituted with nitrogen. The temperature of the solution was raised to 70 ° C. with slow stirring, and polymerization was carried out while maintaining this temperature for 5 hours to obtain a solution of copolymer [A-2].

Solid content concentration of the said solution was 33.4 weight%, and Mw of the copolymer [A-2] was 9,000.

&Lt; Example 1 >

Preparation of Composition Solution

100 parts by weight (solid content) of the solution of the copolymer [A-1] obtained in Synthesis Example 1 as the copolymer [A], 80 parts by weight of KAYARAD DPHA (manufactured by Nippon Kayaku Co., Ltd.) as the polymerizable compound [B], 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one as a photopolymerization initiator [C] (trade name "Irgacure 369", manufactured by Ciba Specialty Chemicals, Inc.) 1 weight The part was dissolved in propylene glycol monomethyl ether acetate so that the solid content concentration was 35% by weight, and then filtered through a Millipore filter having a pore diameter of 0.2 μm to prepare a composition solution (S-1).

(I-1) Formation of Spacer

The composition solution was applied using a spinner on an alkali free glass substrate, and then prebaked on a hot plate at 90 ° C. for 3 minutes to form a coating film having a thickness of 6.0 μm.

The exposure intensity at a wavelength of 365 nm was obtained by using a step (a) in which the exposure gap was 150 µm and the remaining pattern was 10 µm in width and the coating film obtained above was replaced with a nitrogen gas atmosphere in the coating chamber. The exposure was performed with ultraviolet light of 300 W / m 2. Subsequently, development was performed at 25 DEG C for 60 seconds in an aqueous 0.05 wt% potassium hydroxide solution, followed by 1 minute washing in purified water. The spacer was also formed by heating in an oven at 150 ° C. for 120 minutes.

(I-2) Formation of Spacer

Similarly to (I-1), a coating film of 6.0 mu m thickness was formed. The exposure similar to (I-1) was performed using the process (b) which sets the mask and exposure gap similar to (I-1), and makes the inside of an exposure chamber chamber under reduced pressure (20 mmHg). Subsequently, it developed, washed, and heated like (I-1), and formed the spacer.

(I-3) Formation of Spacer

Similarly to (I-1), a coating film having a thickness of 6.0 µm was formed, and then NFC-620 (trade name) (manufactured by JSR Co., Ltd.) was applied under predetermined conditions to form a coating film. The exposure similar to (I-1) was performed using the process (c) which sets the mask and exposure gap similar to (I-1), and interrupts surrounding atmosphere. Subsequently, it developed similarly to (I-1), wash | cleans NFC-620, and simultaneously forms a pattern, wash | cleans and heats, and forms the spacer.

(I-4) Formation of Spacer

After forming a 6.0-micrometer-thick coating film similarly to (I-1) on a 50-micrometer-thick PET film, it bonded to the 100-micrometer-thick ARTON (brand name) (JSR Corporation) product. The same mask and exposure gap as (I-1) were set, and exposure similar to (I-1) was performed using the process (c) which exposes through a PET film. Subsequently, after peeling a PET film, it developed, washed and heated similarly to (I-1), and formed the spacer.

(I-5) Formation of Spacer (Comparative Example)

Similarly to (I-1), the composition solution was applied onto the alkali free glass substrate using a spinner, and then prebaked at 90 ° C. for 3 minutes to form a coating film having a thickness of 6.0 μm.

The exposure gap was 150 micrometers, and exposure to the coating film obtained above by the ultraviolet-ray whose exposure intensity in wavelength 365nm is 300 W / m <2> was carried out in air atmosphere to the coating film obtained above through the mask which is 10 micrometers in length. Subsequently, development was performed at 25 DEG C for 60 seconds in an aqueous 0.05 wt% potassium hydroxide solution, followed by 1 minute washing in purified water. The spacer was also formed by heating in an oven at 150 ° C. for 120 minutes.

(II) evaluation of resolution

The pattern obtained in the above (I) was evaluated as the minimum pattern size at a sensitivity at which the residual film ratio after development (film thickness after development / initial film thickness × 100) was 90% or more. The smaller the pattern size, the better the resolution.

(III) sensitivity evaluation

It can be said that the sensitivity is favorable if the sensitivity at which the residual film ratio after development is 90% or more with respect to the pattern obtained in the above (I) is 1500 J / m 2 or less.

(IV) Evaluation of pattern cross-sectional shape

As a result of observing the cross-sectional shape of the pattern obtained in the above (I) with a scanning electron microscope, it was shown which of the shapes A to C shown in FIG. As shown in A, when the pattern edge is a forward taper, the pattern shape can be said to be good. When the pattern edge is vertically formed as in B, it can be said that the pattern shape is slightly good. In addition, as shown in C, the shape of the reverse taper (the side of the film surface in the cross-sectional shape is longer than the side of the substrate side, the inverted triangle shape) is very likely to peel the pattern during the subsequent rubbing process. This shape was considered to be poor because of its highness.

(V) evaluation of compressive strength

The compressive strength of the spacer obtained in (I) was evaluated using a micro compression tester (MCTM-200, manufactured by Shimadzu Corporation). The amount of deformation when a load of 10 mN was applied using a plane indenter having a diameter of 50 μm was measured (measured temperature: 23 ° C.). When this value is 0.5 or less, compressive strength is favorable. The results are shown in Table 2 below.

(VI) evaluation of friction resistance

AL3046 (manufactured by JSR Co., Ltd.) as a liquid crystal aligning agent was applied to the substrate obtained in the above (I) with a liquid crystal aligning film coating printer, and dried at 180 ° C. for 1 hour to form an alignment film having a dry film thickness of 0.05 μm. It was.

The friction process was performed at the roll rotation speed of 500 rpm and the stage movement speed of 1 cm / sec with the friction machine with the roll wound the nylon cloth to the said coating film. Table 2 shows the presence or absence of wear or peeling of the spacer pattern at this time.

(VII) Evaluation of adhesion

Except not using a pattern mask, it carried out similarly to said (I), the cured film for adhesive evaluation was formed, and the adhesive test was done. The test method conformed to the 8.5.2 checker taping method in the adhesion test of JISK-5400 (1900) 8.5. At this time, the number of remaining checkerboard eyes is shown in Table 2.

(VIII) Evaluation of precipitates

It carried out similarly to said (I) using the 4-inch glass substrate, and the test method followed the 8.5 * 2 checker taping method in the adhesion test of JISK-5400 (1900) 8.5. At this time, the number of remaining checkerboard eyes is shown in Table 2.

(IX) precipitate in developer

It carried out similarly to said (I) using five 4-inch glass substrates, and developed by immersing in 50 cc of developing solution. The developer was stored in the dark at room temperature for 3 days, and the precipitates were visually and microscopically verified. When the crystals were found to be present, they were called 'with precipitates'.

<Examples 2 to 21, Comparative Examples 1 to 3>

A composition solution was prepared in the same manner as in Example 1 except that the kinds and amounts shown in Table 1 below were used as the [A] to [D] components in Example 1, and a spacer was formed and evaluated. The addition amount of [B]-[D] is a weight ratio with respect to 100 weight part of polymeric compounds [A].

In Table 1, the abbreviation of a component shows the following compound.

(B-1): KAYARAD DPHA (product of Nippon Kayaku Co., Ltd.)

(B-2): KAYARAD DPHA-40H (product of Nippon Kayaku Co., Ltd.)

(C-2): 1- [9-ethyl-6- (2-methylbenzoyl) -9.H.-carbazol-3-yl] -ethane-1-onoxime-O-acetate (Ciba specialty) Chemicals company CGI-242)

(C-3): 1,2-octadione-1- [4- (phenylthio) phenyl] -2- (O-benzoyl oxime) (CGI-124 by Ciba specialty chemicals company)

(C-4): 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one (Irucure 907 made by Ciba Specialty Chemicals)

(C-5): 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 (Irucure 369 by Ciba specialty chemicals company)

(D-1): 2,2'-bis (2,4-dichlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole

(D-2): 4,4'-bis (diethylamino) benzophenone

(D-3): 2-mercaptobenzothiazole

In Table 1, "-" indicates that the corresponding component was not added.

According to the present invention, the design size of the mask pattern can be faithfully reproduced at high sensitivity, and the adhesion with the substrate is excellent, and sufficient spacer shape and film thickness can be achieved with an exposure dose of 1500 J / m 2 or less, and the photopolymerization initiator precipitates in the developer. A liquid crystal display comprising a radiation-sensitive resin composition capable of forming a spacer for a liquid crystal display device having excellent strength and heat resistance as well as a problem, a pattern forming process suitable for the radiation-sensitive resin composition, a spacer formed thereby, and the spacer formed thereon. An element may be provided.

Claims (8)

(1) [A] (a1) Copolymer of ethylenically unsaturated carboxylic acid and / or ethylenically unsaturated carboxylic anhydride, (a2) epoxy group-containing ethylenically unsaturated compound and (a3) other ethylenically unsaturated compound, [ B] The coating film of the radiation sensitive composition containing the polymeric compound which has an ethylenically unsaturated bond, and [C] photoinitiator, and whose content of a [C] photoinitiator is 0.2-3.125 weight part with respect to 100 weight part of [B] Forming on a substrate, (2) irradiating at least a portion of the coating film under low oxygen conditions selected from an inert gas atmosphere condition, a vacuum or reduced pressure condition, or a condition in which the surrounding atmosphere is blocked by a cover film; (3) developing process and (4) heating process Spacer forming method comprising a. The method of forming a spacer according to claim 1, wherein the low oxygen condition is an inert gas atmosphere. The method of forming a spacer according to claim 1, wherein the low oxygen condition is a reduced pressure. The method of forming a spacer according to claim 1, wherein the low oxygen condition is a condition in which the surrounding atmosphere is blocked by a cover film. Spacer formed by the method of claim 1. A liquid crystal display device comprising the spacer of claim 5. delete delete

Images