TWI406062B - A photosensitive resin composition for optical spacers, an optical spacers, and a liquid crystal display device - Google Patents

Abstract

A photosensitive resin composition for photosensitive clearance material comprises a resin binder (A), a photo-polymerization compound (B), a photo-polymerization initiator (C) and a solvent (D), the photo-polymerization compound (B) contains a compound of the formula (I) with a content of 5-60 wt% in a total amount of resin binder, photo-polymerization compound (B) and photo-polymerization initiator (C). In formula (I), R1-R6 separately represent H or any group of formula (I-1) to (I-3), at least four groups of R1-R6 are selected from the groups of (I-1) to (I-3) and at least one group of R1-R6 is selected from the groups of (I-2) to (I-3).

Description

Photosensitive resin composition for photo spacer, photo spacer, and liquid crystal display device

The present invention relates to a photosensitive resin composition for a photo spacer.

A spacer is provided between the filter constituting the display device such as a liquid crystal display device or a touch panel and the array substrate to maintain a space between the two substrates. This spacer has been proposed as a photo spacer method in which a spacer is formed using a photosensitive resin composition in place of the conventional spherical particles.

The photosensitive resin composition used in the photo spacer method has proposed a light interval containing a methacrylic acid/allyl methacrylate copolymer as a binder resin and dipentaerythritol hexaacrylate as a photopolymerizable compound. A photosensitive resin composition is used for the object. (Refer to JP-A-2003-302639).

However, when a photo-spacer is formed by using a photosensitive resin composition for a photo spacer disclosed in Japanese Laid-Open Patent Publication No. 2003-302639, there is a problem that the amount of deformation is insufficient.

The present inventors have found that a photosensitive resin composition which can form a photo spacer having few problems as described above has been found to have a large amount of deformation of a photosensitive resin composition containing a certain photopolymerizable compound. Light spacers.

(disclosure of the invention)

An object of the present invention is to provide a photosensitive resin composition which can form a photo spacer having a large amount of deformation.

That is, the present invention provides the following [1] to [6].

[1] A photosensitive resin composition for a photo spacer comprising a binder resin (A), a photopolymerizable compound (B), a photopolymerization initiator (C), and a solvent (D), wherein: The photopolymerizable compound (B) contains a compound represented by the formula (I), and the content of the photopolymerizable compound (B) represented by the formula (I) is relative to the binder resin (A) and photopolymerizability. The total amount of the compound (B) and the photopolymerization initiator (C) is from 5 to 60% by mass.

In the formula (I), R ₁ to R ₆ each independently represent a hydrogen atom or a group of any one of the following formulas (I-1) to (I-3), and at least 4 of R ₁ to R ₆ The base of any of (I-1) to (I-3), the base of at least one of R ₁ to R ₆ is (I-2) or (I-3)]

[2] The composition of the item [1], wherein the content of the photopolymerizable compound (B) represented by the formula (I) is relative to the binder resin (A), the photopolymerizable compound (B), and photopolymerization. The total amount of the initiator (C) is 20 to 40% by mass.

[3] The composition of [1] or [2], wherein the binder resin (A) is a resin obtained by copolymerizing at least two of the compounds (A2) to (A5); (A2): Compound (A3) having an unsaturated bond copolymerizable with (A4): a carboxylic acid having an unsaturated bond (A4): a compound having an unsaturated bond and an epoxy group in one molecule (A5): However, the (A2) to (A5) systems are different from each other.

[4] The composition according to any one of [1] to [3] wherein the photopolymerization initiator (C) contains at least one selected from the group consisting of triazine, acetophenone, and biimidazole. A compound of the group consisting of a ruthenium compound and a ruthenium phosphine oxide compound.

[5] A photo spacer which is formed by using the composition according to any one of [1] to [4].

[6] A liquid crystal display device comprising the photo spacer according to [5].

(to implement the form of the invention)

Hereinafter, the present invention will be described in detail.

The photosensitive resin composition of the present invention is a photosensitive resin composition for a photo spacer, which comprises a binder resin (A), a photopolymerizable compound (B), a photopolymerization initiator (C), and if necessary The other additive (E) is dissolved and dispersed in the solvent (D), and the photopolymerizable compound (B) contains the compound represented by the formula (I), and the content of the compound (B) represented by the formula (I) is relative to the binder. The total amount of the resin (A), the photopolymerizable compound (B), and the photopolymerization initiator (C) is from 5 to 60% by mass.

The binder resin (A) is preferably a resin having alkali solubility or a resin having alkali solubility and having reactivity by light or heat.

In the above-mentioned binder resin (A), for example, at least two of the following compounds (A2) to (A5) ((A2), (A3), (A4), (A5)) are regarded as only 1 For example, a resin obtained by copolymerization of one of two different compounds belonging to (A2) is used.

(A2): Compound (A3) having an unsaturated bond copolymerizable with (A4): a carboxylic acid having an unsaturated bond (A4): a compound having an unsaturated bond and an epoxy group in one molecule (A5): Anhydride

However, (A2)~(A5) are different from each other.

The compound (A2) having an unsaturated bond copolymerizable with (A4) may, for example, specifically be methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, or (methyl) An unsubstituted or substituted unsaturated carboxylic acid alkyl ester such as 2-hydroxyethyl acrylate or aminoethyl (meth) acrylate; containing cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, Methylcyclohexyl (meth)acrylate, cycloheptyl (meth)acrylate, cyclooctyl (meth)acrylate, decyl (meth)acrylate, cyclopentenyl (meth)acrylate, ( Cyclohexene methacrylate, cycloheptenyl (meth) acrylate, cyclooctene (meth) acrylate, decadienyl (meth) acrylate, isobornyl (meth) acrylate, ( Ethyl methacrylate, adamantyl (meth)acrylate, norbornene (meth)acrylate, terpene (meth)acrylate, dicyclopentanyl (meth)acrylate, (meth)acrylic acid An alicyclic unsaturated ester compound such as dicyclopentenyl ester, dicyclopentyloxyethyl (meth)acrylate or dicyclopentenylethyl (meth)acrylate; (meth)acrylic acid Oligo a monosaturated carboxy ester compound of a glycol such as a diol monoalkyl ester; an aromatic carboxyl group-containing unsaturated carboxylate compound such as benzyl (meth)acrylate or phenoxy (meth)acrylate; styrene; , an aromatic vinyl compound such as α -methylstyrene, α -phenylstyrene or vinyltoluene; a vinyl carboxylate such as vinyl acetate or vinyl propionate; (meth)acrylonitrile, α- a cyanidated vinyl compound such as chloroacrylonitrile; an N-substituted malayanium such as N-cyclohexylmaleimide or N-phenylmaleimide or N-benzylmaleimide Amine compounds and the like. These may be used alone or in combination of two or more.

Here, the (meth) acrylate in the present specification means a group composed of at least one acrylate and (meth) acrylate. Further, (meth)acrylic means a group of at least one of acrylic acid and methacrylic acid.

The carboxylic acid (A3) having an unsaturated bond may specifically be, for example, acrylic acid or methacrylic acid. Acrylic acid and methacrylic acid can be used individually or in combination of both. Further, in addition to such acrylic acid or methacrylic acid, a carboxylic acid having another unsaturated group may also be used. Specific examples of the carboxylic acid having another unsaturated group include crotonic acid, itaconic acid, maleic acid, fumaric acid and the like. Further, a hydroxyl group and a carboxyl group may be contained in the same molecule as α- (hydroxymethyl)acrylic acid, and a carboxylic acid having an unsaturated group may be used.

The compound (A4) having an unsaturated bond and an epoxy group in one molecule may, for example, be glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, or (meth) Acrylic acid-β-ethyl glycidyl ester, β-propyl glycidyl (meth)acrylate, β-methyl glycidyl α -ethyl acrylate, 3-methyl (meth)acrylate 3-,4-epoxybutyl butyl ester, 3-ethyl-3,4-epoxybutyl (meth)acrylate, 4-methyl-4,5-epoxy (meth)acrylate The amyl amyl ester, 5-methyl-5,6-epoxyhexyl (meth)acrylate, glycidyl vinyl ether, etc. are preferably, for example, glycidyl (meth)acrylate.

The acid anhydride (A5) is a compound having one acid anhydride in one molecule, and specific examples thereof include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methyl terminal methylene. The tetrahydrofurfuric anhydride, methyltetrahydrophthalic anhydride, trimellitic anhydride or the like is preferably, for example, tetrahydrophthalic anhydride.

The binder resin (A) of the present invention can be obtained by arbitrarily polymerizing the above-mentioned respective compounds, but preferably, for example, a copolymer of (A2) and (A3); and (A2) and (A3) The carboxyl group of (A3) in the copolymer (4) further reacts the copolymer of (A4); the copolymer of (A2) and (A4) to obtain the copolymer 1, and the obtained copolymer 1 is (A3) reacting at an epoxy group derived from (A4) of the copolymer 1 to obtain a copolymer 2; and the obtained copolymer 1 and (A3) are derived from the copolymer 1 (A4) The epoxy group is reacted to obtain the copolymer 2, and the obtained copolymer 2 and (A5) are at least a part of the hydroxyl group formed by the reaction of (A4) and (A3) of the copolymer 1. The (A2) to (A5) copolymer obtained by the reaction.

The copolymer of (A2) and (A3) can be produced under the conditions generally carried out industrially. For example, in a flask equipped with a stirrer, a thermometer, a reflux cooling tube, a dropping funnel, and a nitrogen introduction tube, a solvent is introduced in an amount of 0.5 to 20 times based on the total mass of (A2) and (A3), and the environment inside the flask is from The air is replaced by nitrogen. Thereafter, the temperature of the solvent is raised to 40 to 140 ° C, and then the amount of (A2) and (A3), (A2) and (A3) is used in a total amount of 0 to 20 times by mass based on the mass. a polymerization initiator such as azobisisobutyronitrile or benzoyl peroxide, and a molar amount of (A2) and (A3), and a solution of 0.1 to 10 mol% (at room temperature or under heating) The mixture was dropped into the flask from the dropping funnel for 0.1 to 8 hours, and further stirred at a temperature of 40 to 140 ° C for 1 to 10 hours. Further, in the above step, a part or the whole amount of the polymerization initiator may be fed to the flask side, or a part or the whole amount of (A2) and (A3) may be fed to the flask side. Also, to control the molecular weight or molecular weight distribution. An α -methylstyrene or a thiol compound can also be used as the chain shifting agent. The amount of the α -methylstyrene or the thiol compound to be used is generally 0.005 to 5% by mass based on the total amount of (A2) and (A3). Further, the feeding method or the reaction temperature may be appropriately adjusted in consideration of the amount of heat generated by the manufacturing equipment or the polymerization.

The ratio of the constituent components derived from the respective compounds is preferably in the range of the molar fraction with respect to the total number of moles constituting the constituent components of the above-mentioned copolymer.

The constituent unit derived from (A2): 5~95 mol% is derived from the constituent unit of (A3): 5~95 mol%

Moreover, when the ratio of the above-mentioned constituent components is in the following range, the developing property is good, and it is more preferable.

The constituent unit derived from (A2): 10~90 mol% is derived from the constituent unit of (A3): 10~90 mol%

Further, in the copolymer obtained by reacting the above-mentioned (A2) and (A3) copolymer with (A4) at the site derived from the carboxyl group of (A3) of the above-mentioned copolymer, the addition of (A4) The amount is usually 5 to 60 mol%, more preferably 10 to 50 mol%, based on the carboxyl group of (A3) of the above copolymer.

When the composition ratio of (A4) is within the above range, excellent photosensitivity and sufficient photocurability or thermosetting property can be obtained, and the reliability is excellent, which is preferable.

Further, the above (A2) and (A4) are copolymerized to obtain a copolymer 1, and the obtained copolymer 1 and (A3) are reacted at an epoxy group derived from (A4) of the copolymer 1. The copolymer 2 is obtained, and the obtained copolymer 2 is further reacted with (A5) by a hydroxyl group formed by the reaction of (A4) and (A3) of the copolymer 1 (A2) to (A5). The copolymer is preferably used.

The aforementioned (A2) to (A5) copolymer can be produced as follows.

First, in order to obtain the copolymer 1, (A2) and (A4) are copolymerized. This copolymerization is carried out under normal conditions. For example, in a flask equipped with a stirrer, a thermometer, a reflux cooling tube, a dropping funnel, and a nitrogen introduction tube, a solvent of 0.5 to 20 times is introduced with respect to the mass ratio of (A2) and (A4), and the flask environment is introduced. Replaced from air to nitrogen. Thereafter, after raising the temperature of the solvent to 40 to 140 ° C, azobisisobutyronitrile or benzoic acid is used in a solvent having a mass ratio of 0 to 20 times based on the total amount of (A2) and (A4). The polymerization initiator of the thiol group or the like is added to the total number of moles of (A2) and (A4) by adding 0.1 to 10 mol% of the solution (stirring at room temperature or under heating) from the dropping funnel for 0.1 to 8 hours. The mixture was dropped into the flask, and further stirred at 40 to 140 ° C for 1 to 10 hours.

Further, in the above step, one part or the whole amount of the polymerization initiator may be fed to the flask side, or one part or the whole amount of (A2) and (A4) may be fed to the flask side. Also, to control the molecular weight or molecular weight distribution. An α -methylstyrene or a thiol compound can also be used as the chain shifting agent. The amount of use of the α -methylstyrene or the thiol compound is generally 0.005 to 5% based on the total mass of (A2) to (A3). Further, the feeding method or the reaction temperature may be appropriately adjusted in consideration of the amount of heat generated by the manufacturing equipment or the polymerization.

The ratio of the constituent components derived from the respective compounds to the total number of moles constituting the constituent components of the above-mentioned copolymer 1 is preferably in the range of the following.

The constituent unit derived from (A2): 2~97 mol% is derived from the constituent unit of (A4): 3~98 mol%

Further, when the ratio of the above-mentioned constituent components is in the following range, the balance between flexibility and heat resistance is good, and a preferred trunk polymer can be obtained, which is more preferable.

Component unit derived from (A2): 15~85 mol% derived from (A4) constituent unit: 15~85 mol%

Next, it is added to the above-mentioned copolymer 1 (A3) to impart photocurability or thermosetting property to the binder resin (A).

The reaction of the copolymer 1 and (A3) can be carried out, for example, under the conditions described in JP-A-2001-89533. Specifically, the atmosphere in the flask is replaced with nitrogen from air, and in the flask, the molar fraction of the constituent unit derived from (A4) of the above-mentioned copolymer 1 is set to 5 to 100 mol% (A3). In the case of a reaction catalyst of a carboxyl group and an epoxy group, for example, tris-methylaminomethylphenol is placed in a mass ratio of 0.01 to 5% with respect to the total of (A2) to (A4); In the polymerization inhibitor, for example, hydroquinone is placed in a total amount of 0.001 to 5% based on the total amount of (A2) to (A4), and reacted at 60 to 130 ° C for 1 to 10 hours. The aforementioned copolymer 1 is reacted with (A3) to obtain a copolymer 2. Moreover, the heat of the manufacturing equipment or the heat of polymerization may be considered, and the feed-in or reaction temperature may be appropriately adjusted.

The amount of (A3) added is usually from 5 to 100 mol%, preferably from 10 to 100%, based on the epoxy group (from (A4) component) in the resin obtained by copolymerizing (A2) and (A4). 95% by mole.

When the composition ratio of (A4) is within the above range, sufficient photocurability or thermosetting property can be obtained, and the reliability is excellent, which is preferable.

Finally, the copolymer 2 is reacted with (A5) to impart alkali solubility to the binder resin (A).

The reaction of the copolymer 2 and (A5) can be carried out, for example, under the conditions described in JP-A-2001-89533. Specifically, in the flask, 5 to 100 mol% (A5) is placed in relation to the constituent unit derived from (A3) of the above-mentioned copolymer 2, and in the case of the reaction catalyst, for example, For example, the triethylamine is placed in a mass ratio of 0.01 to 5% with respect to the total of (A2) to (A4), and the reaction is carried out for 1 to 10 hours at a temperature of 60 to 130 ° C to cause the aforementioned copolymer. 2 reacts with (A5). Moreover, the heat of the manufacturing equipment or the heat of polymerization may be considered, and the feed-in or reaction temperature may be appropriately adjusted.

The amount of addition of (A5) is usually from 5 to 100 mol%, preferably from 10 to 95 mol%, based on the number of moles of the alcoholic hydroxyl group of the copolymer 2 (derived from the (A3) component).

More specifically, the binder resin (A) is preferably at least one copolymer selected from the group consisting of the constituent units (U1), (U2) and (U3), and the constituent unit (U1). A group of copolymers (U1-2-4) composed of (U2) and (U4).

Here, the constituent unit (U1) indicates that at least one of the constituent units is selected from the group consisting of the constituent unit (U1-1) and the constituent unit (U1-2).

R ¹ each independently represents either a hydrogen atom, a methyl group, or a hydroxymethyl group.

R ² R ⁵ are diagrams may also be substituted with the phenyl group, -COOH, or -C (= O) OR ⁵ group.

R ³ represents an oxygen atom, a sulfur atom, -NH-, or -N(R ⁵ )- group.

R ⁴ represents a divalent group described below.

-CH ₂ . CH ₂ -,

Here, R ⁵ represents methyl, ethyl, propyl, butyl, pentyl, hexyl, cyclohexyl, phenyl, benzyl, naphthyl, adamantyl, isobornyl, dicyclopentanyl, Any one of a dicyclopentenyl group, a dicyclopentenyloxyethyl group, a dicyclopentenyloxyethyl group, or a hydroxyl group.

The polystyrene-equivalent weight average molecular weight of the binder resin (A) is preferably from 3,000 to 100,000, more preferably from 5,000 to 30,000. When the weight average molecular weight of the binder resin (A) is within the above range, the coating property is good, and it is difficult to cause a film to be reduced during development, and further, the release property of the unexposed portion tends to be good at the time of development, which is preferable.

The molecular weight distribution [weight average molecular weight (Mw) / number average molecular weight (Mn)] of the binder resin (A) is preferably from 1.5 to 6.0, more preferably from 1.8 to 4.0. If the molecular weight distribution is in the above range, the image forming property is excellent, which is preferable.

The content of the binder resin (A) used in the photosensitive resin composition for a photo spacer of the present invention is preferably 5 to 90% by mass based on the solid content of the photosensitive resin composition for the photo spacer. More preferably, it is 10 to 70% by mass. When the content of the binder resin (A) is within the above range, the solubility in the developing solution is sufficient, and it is difficult to generate a developing residue on the unexposed portion of the substrate, and the pixel portion of the exposed portion is large in development. It is difficult to cause a film to be reduced, and the unexposed portion has a good tendency to be removed, which is preferable.

The photopolymerizable compound (B) used for the photosensitive resin composition for a photo spacer of the present invention contains a compound represented by the formula (I) or a compound represented by the formula (I).

In the formula (I), R ₁ to R ₆ each independently represent a hydrogen atom or a group of any one of the following formulas (I-1) to (I-3), and at least 4 of R ₁ to R ₆ The base of any of (I-1) to (I-3), the base of at least one of R ₁ to R ₆ is (I-2) or (I-3)]

The compound represented by the formula (I) may, for example, be a polyfunctional acrylate compound in which dipentaerythritol is subjected to lactone modification. Specifically, for example, KAYARAD DPCA-60 (trade name) manufactured by Nippon Kayaku Co., Ltd., and KAYARAD DPCA-120 (trade name) may be used.

In the composition of the present invention, a polymerizable compound other than the binder resin (A) and the photopolymerizable compound (B) of the present invention may be contained in the composition of the present invention, and the compound may be used in combination. In addition to the functional monomer, a bifunctional monomer or a trifunctional or higher polyfunctional monomer (except for the compound represented by the formula (I)).

Specific examples of the monofunctional monomer include mercaptophenylcarbitol acrylate, 2-hydroxy-3-phenoxy acrylate, 2-ethylhexyl carbitol acrylate, and 2-hydroxyethyl acrylate. , N-vinyl pyrrolidone, and the like.

Specific examples of the bifunctional monomer include, for example, 1,6-hexanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, and triethyl ethane. Diol (meth) acrylate, bis (acryloyloxyethyl) ether of bisphenol A, 3-methyl pentanediol di (meth) acrylate, and the like.

Specific examples of the trifunctional or higher polyfunctional monomer include, for example, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol-5. A reaction product of (meth) acrylate, dipentaerythritol hexa(meth) acrylate, pentaerythritol tri(meth) acrylate and an acid anhydride, dipentaerythritol penta (meth) acrylate and an acid anhydride, and the like.

Among these, a trifunctional or higher polyfunctional monomer is preferably used.

The content of the photopolymerizable compound (B) is 100 parts by mass based on the total of the binder resin (A), the photopolymerizable compound (B), and the photopolymerization initiator (C) in the photosensitive resin composition for a photo spacer. It must be 5 to 60 parts by mass, preferably 10 to 50 parts by mass, more preferably 20 to 40 parts by mass. When the content of the photopolymerizable compound (B) is within the above range, the amount of plastic deformation of the photo spacer is large, and the surface smoothness tends to be good, which is preferable.

The photopolymerization initiator (C) contained in the photosensitive resin composition for a photo spacer of the present invention may, for example, be an acetophenone compound, a bisimidazole compound, an anthraquinone compound or a triazine compound. In addition, by using the photopolymerization initiator (C) and the photopolymerization initiation aid (C-1) in combination, the photosensitive resin composition has a higher sensitivity, and the productivity when forming a pattern is used. Improve, so good. However, when the absorption wavelength of the photopolymerization initiation aid (C-1) is on the longer wavelength side than the absorption wavelength of the photopolymerization initiator (C), the transmittance of the formed film becomes lower, so it is preferable to avoid the loss. The degree of the effect of the invention is used.

The aforementioned acetophenone-based compound may, for example, be diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, or 2-hydroxy- 1-[4-(2-hydroxyethoxy)phenyl]-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-(4-methylthiobenzene) 2-morpholinylpropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)butan-1-one, acetophenone Specific examples thereof include 2-(2-methylbenzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone and 2-(3-methylbenzylmethyl). -2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-(4-methylbenzyl)-2-dimethylamino-1-(4- Morpholinylphenyl)-butanone, 2-(2-ethylbenzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-(2- Propylbenzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-(2-butylbenzyl)-2-dimethylamino- 1-(4-morpholinylphenyl)-butanone, 2-(2,3-dimethylbenzyl) 2-Dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-(2,4-dimethylbenzyl)-2-dimethylamino-1-(4) -morpholinylphenyl)-butanone, 2-(2-chlorobenzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-(2- Bromobenzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-(3-chlorobenzyl)-2-dimethylamino-1- (4-morpholinylphenyl)-butanone, 2-(4-chlorobenzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-( 3-bromobenzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-(4-bromobenzyl)-2-dimethylamino- 1-(4-morpholinylphenyl)-butanone, 2-(2-methoxybenzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone , 2-(3-methoxybenzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-(4-methoxybenzyl) -2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-(2-methyl-4-methoxybenzyl)-2-dimethylamino- 1-( 4-morpholinylphenyl)-butanone, 2-(2-methyl-4-bromobenzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone , 2-(2-bromo-4-methoxybenzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone, 2-hydroxy-2-methyl- An oligomer of 1-[4-(1-methylvinyl)phenyl]propan-1-one or the like.

The aforementioned biimidazole-based compound may, for example, be 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenylbisimidazole, 2,2'-bis (2,3- Dichlorophenyl)-4,4',5,5'-tetraphenylbisimidazole (for example, JP-A-6-75372, JP-A-6-75373, etc.), 2, 2'-double (2) -Chlorophenyl)-4,4',5,5'-tetraphenylbisimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetra(alkoxy) Biphenyl)biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetrakis(dialkoxyphenyl)bisimidazole, 2,2'-bis ( 2-chlorophenyl)-4,4',5,5'-tetrakis(trialkoxyphenyl)bisimidazole (for example, JP-A-48-38403, JP-A-62-174204, etc.), 4 The imidazole compound in which the phenyl group at the 4', 5, and 5'-position is substituted with a carbonyl alkoxy group (for example, see JP-A-7-10913, etc.), etc., preferably, for example, 2,2'-bis (2) -Chlorophenyl)-4,4',5,5'-tetraphenylbisimidazole, 2,2'-bis(2,3-dichlorophenyl)-4,4',5,5'-four Phenyl diimidazole.

The above-mentioned oxime-based compound may, for example, be O-ethoxycarbonyl- α -oxyimino-1-phenylpropan-1-one, a compound represented by the formula (a), and substituted by the formula (b). Compounds, etc.

The aforementioned triazine-based compound may, for example, be 2,4-bis(trichloromethyl)-6-(4-methoxyphenyl)-1,3,5-triazine or 2,4-bis(trichloro). Methyl)-6-(4-methoxynaphthyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-piperidin-1,3,5-triazine , 2,4-bis(trichloromethyl)-6-(4-methoxystyryl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-( 2-(5-methylfuran-2-yl)ethynyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(2-(furan-2-yl) Vinyl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(2-(4-diethylamino-2-methylphenyl)vinyl)- 1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(3,4-dimethoxyphenyl)vinyl]-1,3,5-triazine Wait.

In addition, as long as the effect of the present invention is not impaired, a photopolymerization initiator or the like which is generally used in the field can be used in combination, and examples thereof include a benzoin-based compound, an acetophenone-based compound, and a thioxanthone-based compound. A photopolymerization initiator such as a lanthanide compound.

More specifically, for example, the following compounds may be used, and these may be used alone or in combination of two or more.

The benzoin-based compound may, for example, be benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether or benzoin isobutyl ether.

The acetophenone-based compound may, for example, be acetophenone, methyl ortho-benzoyl benzoate, 4-phenylacetophenone or 4-benzylidene-4'-methyldiphenyl sulfide. 3,3',4,4'-tetra(t-butylperoxycarbonyl)acetophenone, 2,4,6-trimethylacetophenone, and the like.

Examples of the thioxanthone-based compound include 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthiaxanone, and 2,4-dichlorothiazepine. Anthrone, 1-chloro-4-propoxythioxanthone, and the like.

The aforementioned lanthanoid compound may, for example, be 9,10-dimethoxyanthracene, 2-ethyl-9,10-dimethoxyanthracene, 9,10-diethoxy fluorene, 2-ethyl-9. , 10-diethoxyanthracene, and the like.

Others may also be used in combination with 2,4,6-trimethylbenzimidyldiphenylphosphine oxide, 10-butyl-2-chloroindanone, 2-ethylhydrazine, benzyl, 9,10-phenanthrene A photopolymerization initiator such as ruthenium, camphorquinone, methyl phenylglyoxylate or a titanocene compound.

Further, the photopolymerization initiator having a group which causes chain shift can be used in combination with the one described in JP-A-2002-544205.

The photopolymerization initiator having a group which causes the chain shift is exemplified by the compounds represented by the following formulas (2) to (7).

A photopolymerization initiator having a group which causes the aforementioned chain shift can be used as a constituent component (A2) of the copolymer 1. Then, the binder resin (A) obtained by using (A2) can be used in the binder resin of the present invention.

Further, the photopolymerization initiator may be used in combination with a photopolymerization initiation aid (C-1). The photopolymerization initiation aid is preferably an amine compound and a carboxylic acid compound described below, and the amine compound is more preferably an aromatic amine compound. However, when the absorption wavelength of the photopolymerization initiation aid (C-1) is on the longer wavelength side than the absorption wavelength of the photopolymerization initiator (C), the transmittance of the formed film becomes lower, so it is preferable to avoid the loss. The degree of the effect of the invention is used.

Specific examples of the photopolymerization initiation aid include aliphatic amine compounds such as triethanolamine, methyldiethanolamine, and triisopropanolamine, methyl 4-dimethylaminobenzoate, and 4-dimethylamine. Ethyl chlorate, isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 2-dimethylaminoethyl benzoate, N, N - dimethyl-p-toluidine, 4,4'-bis(dimethylamino)acetophenone (general name: Micheler's ketone), 4,4'-bis(dimethylamino)benzene An aromatic amine compound of ethyl ketone or the like.

Examples of the carboxylic acid compound include phenylthioacetic acid, methylphenylthioacetic acid, ethylphenylthioacetic acid, methylethylphenylsulfuric acid, dimethylphenylsulfuric acid, and methoxyphenylthioacetic acid. Aroma of dimethoxyphenylthioacetic acid, chlorophenylthioacetic acid, dichlorophenylthioacetic acid, N-phenylglycine, phenoxyacetic acid, naphthylthioacetic acid, N-naphthylglycine, naphthyloxyacetic acid, etc. Family of acetic acid and the like.

The content of the photopolymerization initiator (C) is preferably 0.1 to 40 parts by mass, more preferably 1 to 30 parts by mass, per 100 parts by mass of the total of the binder resin (A) and the photopolymerizable compound (B).

When the photopolymerization initiation aid (C-1) is used, the content thereof is preferably from 0.1 to 50 parts by mass, more preferably from 0.1 to 40 parts by mass, based on the above-mentioned basis.

When the content of the photopolymerization initiator (C) is in the above range, the photosensitive resin composition for a photo spacer has high sensitivity, and the surface of the photo spacer formed by using the photoreceptor forming photosensitive resin composition described above is used. The smoothness tends to be good, so it is good. In addition to the above, if the amount of the photopolymerization initiation aid (C-1) is within the above range, the sensitivity of the photosensitive resin composition for forming a photo spacer obtained is changed to be high, and the photo spacer for use is used. The productivity of the pattern substrate formed of the resin composition tends to be improved, which is preferable.

The solvent (D) to be contained in the photosensitive resin composition for a photo-spacer of the present invention is, for example, various organic solvents used in the field of the photosensitive resin composition.

Specific examples thereof include ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, and ethylene glycol monobutyl ether; Diethylene glycol dialkyl ethers such as diol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether and diethylene glycol dibutyl ether; methyl cellosolve Ethylene glycol alkyl ether acetates such as acetate and ethyl cellosolve acetate; propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate Alkyl glycol alkyl ether acetates such as methoxybutyl acetate and methoxypentyl acetate; aromatic hydrocarbons such as benzene, toluene, xylene and trimethylbenzene; methyl ethyl ketone, Ketones such as acetone, methyl amyl ketone, methyl isobutyl ketone and cyclohexanone; alcohols such as ethanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol and glycerin; An ester of ethyl ethoxypropionate or methyl 3-methoxypropionate; a cyclic ester of γ-butyrolactone or the like.

Among the above-mentioned solvents, in terms of coatability and drying property, an organic solvent having a boiling point of 100 to 200 ° C is preferably used among the above solvents, and more preferably an alkyl glycol glycol alkyl ether acetate can be used. Esters, ketones, ethyl 3-ethoxypropionate and methyl 3-methoxypropionate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ring Hexanone, ethyl 3-ethoxypropionate, methyl 3-methoxypropionate.

These solvents (D) may be used alone or in combination of two or more.

The content of the solvent (D) in the photosensitive resin composition for a photo-spacer of the present invention is preferably 60 to 95% by mass, and more preferably 70, based on the photosensitive resin composition for forming a photo spacer. ~90% by mass. If the content of the solvent (D) is in the above range, spin coater, slit type and spin coater, slit coater (sometimes referred to as die coater, curtain flow coating) When the coating device such as a cloth or an inkjet is applied, the coating property tends to be good, which is preferable.

In the photosensitive resin composition for a photo spacer of the present invention, a filler, other polymer compound, a surfactant, an adhesion promoter, an antioxidant, an ultraviolet absorber, a coagulant, and a chain shifting agent may be used in combination as needed. Other compounds ((E) component).

The filler may, for example, be glass, vermiculite, alumina or the like.

Other polymer compounds are exemplified by epoxy resins (commercially available from Mitsui Chemicals Co., Ltd.) Tecmoa VG 3101L (trade name), Sumitomo Chemical Co., Ltd. Sumi Epoxy series (trade name), Japan epoxy resin (shares) ) Epikote series (trade name), etc., curable resin such as maleic imine resin or polyvinyl alcohol, polyacrylic acid, polyethylene glycol monoalkyl ether, polyfluoroalkyl acrylate, polyester, poly A thermoplastic resin such as urethane or the like.

As the surfactant, a commercially available surfactant can be used, and examples thereof include a surfactant such as a polyfluorene-based, a fluorine-based, an ester-based, a cationic-based, an anionic-based, nonionic-based or amphoteric surfactant, and these can be used alone. Two or more types may be used in combination. Examples of the above-mentioned surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyethylene glycol diesters, sorbitan fatty acid esters, and fatty acid-modified polyesters. In addition to the tertiary amine-modified polyurethanes and polyethyleneimine, the trade name is KP (Shin-Etsu Chemical Co., Ltd.), Polyfolw (Kyoei Chemical Co., Ltd.), EFTOP (Tohkem). Products, Ltd., Megaface (Daily Ink Chemical Industry Co., Ltd.), Fluorid (Sumitomo 3M (share) system), Asahi Guard, saflow (above, Asahi Glass Co., Ltd.), Solsperse (made by Zeneca), EFKA (made by EFKA CHEMICALS), PB821 (made by Ajinomoto Co., Ltd.), etc.

Specific examples of the adhesion promoter include vinyl trimethoxy decane, vinyl triethoxy decane, vinyl tris(2-methoxyethoxy) decane, and N-(2-aminoethyl)-3. -Aminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 3-epoxypropanepropyltrimethoxydecane, 3-epoxypropanepropylmethyldimethoxydecane , 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane, 3-chloropropylmethyldimethoxydecane, 3-chloropropyltrimethoxydecane, 3-methylpropene oxime Oxypropyltrimethoxydecane, 3-hydrothiopropyltrimethoxydecane, and the like.

Specific examples of the antioxidant include 2,2'-thiobis(4-methyl-6-tert-butylphenol) and 2,6-di-t-butyl-4-methylphenol.

Specific examples of the ultraviolet absorber include 2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chlorobenzotriazole and alkoxyacetophenone.

Further, the aggregating agent may specifically be, for example, sodium polyacrylate or the like.

The chain shifting agent may, for example, be a dodecyl mercaptan or 2,4-diphenyl-4-methyl-1-pentene.

The photosensitive resin composition for a photo-spacer of the present invention can be easily adjusted by mixing the components (A) to (D) and the component (E) as needed in an arbitrary order.

The photoreceptor photosensitive resin composition is applied to a substrate by, for example, the following method, and photohardening and development are carried out to form a pattern. First, the composition is applied onto a substrate (generally a glass or a film) or a layer composed of a solid component of another photosensitive resin composition previously formed to form a photosensitive resin composition layer. The coating system can be carried out using a known device such as a spin coater, a slit coater, a curtain flow coater, or a rod coater.

The coating and the formed photosensitive resin composition layer are obtained by prebaking to remove volatile components such as a solvent to form a smooth coating film. The thickness of the coating film at this time is generally about 1 to 6 μm . The coating film thus obtained is irradiated with ultraviolet rays through a mask for forming a pattern of interest. In this case, the entire exposed portion is uniformly irradiated with parallel rays, and it is preferable to use a device such as a mask aligner or a stepper for aligning the correct position of the glass and the substrate. After that, the coating film which has been hardened is brought into contact with the aqueous alkali solution to dissolve the non-exposed portion, and development is carried out to obtain the desired pattern shape. The development method may be any one of a liquid-filling method, a dipping method, and a spraying method. Further, the substrate can be tilted or at an appropriate angle during development. After the development, the water is washed, and further, after the need to maintain the temperature range of 150 to 230 ° C for 10 to 60 minutes to perform post-baking.

The developing solution used for the development after the patterning exposure is generally an aqueous solution containing a basic compound and a surfactant.

The basic compound may also be an inorganic or organic basic compound. Specific examples of the inorganic basic compound include sodium hydroxide, potassium hydroxide, disodium hydrogen phosphate, sodium dihydrogen phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, potassium dihydrogen phosphate, sodium citrate, and potassium citrate. , sodium carbonate, potassium carbonate, sodium hydrogencarbonate, potassium hydrogencarbonate, sodium borate, potassium borate, ammonia, and the like.

Specific examples of the organic basic compound include tetramethylammonium hydroxide, 2-hydroxyethyltrimethylammonium hydroxide, monomethylamine, dimethylamine, trimethylamine, monoethylamine, and Ethylamine, triethylamine, monoisopropylamine, diisopropylamine, ethanolamine, and the like. These inorganic and organic basic compounds may be used alone or in combination of two or more. The concentration of the basic compound in the alkali developing solution is preferably from 0.01 to 10% by mass, more preferably from 0.03 to 5% by mass.

The surfactant in the alkali developing solution may be any of a nonionic surfactant, an anionic surfactant, or a cationic surfactant.

Specific examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene aryl ether, polyoxyethylene alkyl aryl ether, other polyoxyethylene derivatives, and oxyethylene/oxypropylene blocks. Copolymer, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, glycerin fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene alkyl Amines, etc.

The anionic surfactant may, for example, be a sodium alcohol lauryl sulfate or a higher alcohol sulfate salt of sodium oleyl sulfate, an alkyl sulfate of sodium lauryl sulfate or ammonium lauryl sulfate, or a dodecylbenzene. An alkyl aryl sulfonate such as sodium sulfonate or sodium dodecyl naphthalene sulfonate.

Specific examples of the cationic surfactant include stearylamine hydrochloride or an amine salt of lauryl trimethylammonium chloride or a fourth-order ammonium salt.

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

The concentration of the surfactant in the alkali developing solution is generally 0.01 to 10% by mass, preferably 0.05 to 8% by mass, more preferably 0.1 to 5% by mass.

Coating, drying, pattern exposure of the obtained dried coating film, and subsequent so-called development of the photosensitive resin composition as described above, on the substrate or on the color filter substrate Or a photo spacer is formed on the substrate for liquid crystal driving.

Further, this photo spacer can be used for a liquid crystal display device. Further, in the liquid crystal display device, the Multi-domain Vertical Alignment (hereinafter, MVA) liquid crystal display device having improved field of view is provided on the base of the alignment film, and a structure is partially provided to form a protrusion, and even if such a structure is formed, A photo spacer formed using the photosensitive resin composition of the present invention is useful. Further, when the photosensitive resin composition for a photo-spacer of the present invention is used, a hole-forming mask can be used for the pattern exposure of the dried coating film, and a hole can be formed, which is used as an interlayer insulating film. Further, when the photosensitive resin composition for a photo spacer of the present invention is used, when the dried coating film is exposed, a resin film can be formed by exposure, heat curing or only heat curing without using a photomask, and the resin film can be used as a resin film. Overlay.

The film thickness difference in the surface of the photo spacer used in the photosensitive resin composition for a photo spacer of the present invention is small, for example, a film thickness of 1 to 6 μm , and the in-plane film thickness difference is 0.15 μm or less. Further formed to be 0.05 μm or less. Therefore, the optical spacers thus obtained are excellent in smoothness, and by incorporating them into a color liquid crystal display device, it is possible to manufacture a liquid crystal display device of superior quality at a higher yield.

The method of manufacturing a liquid crystal display device can exemplify the following method.

The photosensitive resin composition for a photo-spacer of the present invention is applied and dried by a TFT array substrate having a step of forming an alignment film and a rubbing step, and the dried coating film on the obtained substrate is patterned and exposed. Then, a so-called development operation is performed to manufacture a substrate with a photo spacer. Then, the color filter with the ITO film and the substrate with the photo spacer are bonded to each other by the ITO film forming surface and the photo spacer forming surface, and the light between the color filter and the TFT array substrate is bonded. The spacer injects liquid crystal into the formed space, and by sealing the periphery, a liquid crystal display device can be manufactured.

In the photosensitive resin composition for a photo-spacer of the present invention, the storage stability is good and the sensitivity is high. Therefore, by using the photosensitive resin composition, a photo spacer having a large plastic deformation amount can be formed.

Example

Hereinafter, the present invention will be described in more detail based on the examples, but the invention is of course not limited by the examples.

Examples 1, 2 and Comparative Example 1

The structure of the binder resin Aa used in Example 1 and the molar ratio and the like are shown in the formula (X) and Table 1. In Table 1, a~d indicates the molar ratio.

Description of the constituent units

a: a constituent unit derived from (A2) in the copolymer 1.

b: a constituent unit derived from (A2) in the copolymer 1.

c: a constituent unit derived from the (A3) reaction in a constituent unit derived from (A4) in the copolymer 1.

d: a constituent unit derived from the reaction of (A5) at a site derived from (A3) in the copolymer 2.

The measurement of the polystyrene-equivalent weight average molecular weight (Mw) and the number average molecular weight (Mn) of the above-mentioned binder polymer was carried out by the GPC method under the following conditions.

Device: HLC-8120GPC (Tosoh system)

Pipe string: TSK-GELG4000HXL+TSK-GELG2000HXL (series connection)

Column temperature: 40 ° C

Solvent: THF

Flow rate: 1.0 mL / min

Injection volume: 50μL

Detector: RI

Determination of sample concentration: 0.6% by mass (solvent: THF)

Standard materials for calibration: TSK STANDARD POLYSTYRENE F-40, F-4, F-1, A-2500, A-500 (made by Tosoh)

The ratio of the weight average molecular weight and the number average molecular weight obtained above was defined as a molecular weight distribution (Mw/Mn).

The formulation compositions of the examples and comparative examples are shown in Table 2. The numerical values in Table 2 indicate the parts by mass.

A 2 square inch glass substrate (#1737: manufactured by Corning Incorporated) was washed with a neutral detergent, water, and alcohol in order, and then dried. On the glass substrate, the photosensitive resin composition (Table 2) was exposed to an exposure amount (365 mm) of 100 mJ/cm ² , developed, washed, and the film thickness after post-baking was 4.7 μm . Apply, then, in a clean room, pre-bake at 100 ° C for 3 minutes. After cooling, the substrate coated with the photosensitive resin composition and the quartz glass mask (having a pattern of a square having a side of 10 μm and a space of 100 μm from the spacer) were 150 μm , and the use was super. A high-pressure mercury lamp (USH-250D; manufactured by Ushio Electric Co., Ltd.) was irradiated with light at an exposure pressure (365 mm) of 100 mJ/cm ² under atmospheric pressure. Thereafter, the coating film (with a magnetic stirrer of 300 rpm) was immersed in a developing solution containing 0.12% by mass of a nonionic surfactant and 0.05% by mass of potassium hydroxide in a water-based developing solution at 80 ° C for 80 seconds. After the image was washed, it was post-baked at 220 ° C for 30 minutes to obtain a hardened resin pattern.

The results of measurement and the like in the following items of the obtained cured resin pattern are shown in Table 3.

(Description in Table 3)

Surface smoothness: The basis of the surface smoothness is a visual observation of the surface, and if it has a gloss, it is represented by ○, and a white turbidity (opaque) is represented by ×.

Line width: The dimensions of the two sides in the bottom of the pattern were measured using an SEM (Model S-4100; manufactured by Hitachi, Ltd.), and the average value of the obtained two sides was obtained.

Shape: A cross section perpendicular to the substrate of the pattern or the like, and the cross section is observed using the same SEM as described above. If the ridge line of the pattern is less than 90 degrees on the substrate, it is marked as a push-pull shape, and if it is greater than 90 degrees, it is marked as a reverse push-up shape.

Total displacement: Using a dynamic ultra-micro hardness tester (DUH-W201S; manufactured by Shimadzu Corporation), the total displacement ( μm ) was measured under the following conditions. Here, in general, if the amount of shaping displacement is large, the total displacement amount is also large.

Test mode: Load-except load test Test force: 5gf (SI unit conversion value: 0.049N) Load connection degree: 0.45gf/sec (SI unit conversion value: 0.0044N/sec) Hold time: 5 seconds Pressure: Conical table Pressure retention (diameter: 50 mm ψ) Storage stability: The viscosity change rate at 23 ° C for about 3 months was determined by the following formula.

Viscosity change rate (%) = [(viscosity after storage) / viscosity before storage] × 100

Linear expansion coefficient: After baking the photosensitive resin composition on a 4-inch wafer, it was formed into a film of 0.3 μm . At this time, the same operation as that of the glass substrate formed of 2 square inches was performed without using a photomask and omitting the development step.

The film thickness obtained by using an oblique incident X-ray analyzer (X'Pert MRD; manufactured by Philips) was measured at a film thickness of 30 ° C to 200 ° C. Further, X-ray output: 45 kV/40 mA, X-ray: CuKα1 line, environment: carried out with nitrogen.

Further, the unit of the coefficient of linear expansion is 10 ^{- 6} / °C.

Thermal analysis: In the operation of forming a cured resin pattern, the same operation was carried out without using a photomask, and the same operation was carried out to obtain a cured coating film having a film thickness of 3 μm . The hardened coating film was scraped off with a razor, and the heating loss at 240 ° C for 1 hour was measured (the weight of the sample when the temperature reached 240 ° C was 100, and the mass after 240 ° C × 1 hour of temperature retention was expressed as a percentage).

Device: Differential thermal and thermal weight simultaneous measuring device (TG/DTA220: Seiko Instruments) The measuring environment: nitrogen and nitrogen flow rate: 300 mL/min

It is understood that the photosensitive resin composition for photo spacers of Examples 1 and 2 containing the photopolymerizable compound represented by the formula (1) has a large total shift amount, and further has a smooth surface and a pattern shape. In the photosensitive resin composition for a photo-spacer of Comparative Example 1 which does not contain the photopolymerizable compound represented by the formula (1), the total amount of displacement is small.

Example 3, Comparative Example 2, Comparative Example 3

In Example 3, Comparative Example 2, and Comparative Example 3, the structure Ab, the composition, and the like of the resin used as the binder resin (A) are shown in the formula (Y) and Table 4. In Table 4, a~d represents the molar ratio.

The evaluation was carried out in the same manner as in Example 1 in the composition shown in Table 5. The results are shown in Table 6.

Description of the constituent units

a: a constituent unit derived from (A2) in the copolymer 1.

b: a constituent unit derived from (A2) in the copolymer 1.

c: a constituent unit derived from (A2) in the copolymer 1.

d: a constituent unit derived from (A3) in the copolymer 1.

e: a constituent unit derived from the reaction of (A4) by a constituent unit derived from (A3) in the copolymer 1.

The measurement of the polystyrene-equivalent weight molecular weight and the number average molecular weight of the resin Ab was carried out in the same manner as in Example 1.

<Preparation of photosensitive resin composition for photo spacers>

The formulation compositions of the examples and comparative examples are shown in Table 5. The numerical values in Table 5 indicate the parts by mass.

The results of the evaluation are shown in Table 6.

Follow-up test

The glass substrate (#1737; manufactured by Corning Co., Ltd.) which forms a hardened resin pattern was cut into 1 cm × 5 cm, and the same size of the glass substrate (#1737; manufactured by Corning) was superimposed in a cross shape via a hardened resin pattern. The area was 1 cm ² ), and it was pressure-bonded under the pressure of 300 Pa at 150 ° C for 1 hour.

After the test piece was taken out, and after cooling to room temperature, the bonded substrate was peeled off, and the substrate was formed on the cured resin pattern formed using the composition of Example 1-3, but was formed using the composition of Comparative Example 1. The substrate in the hardened resin pattern is not followed. Further, in the compositions of Comparative Examples 2 to 3, the cured resin pattern could not be formed (the film remained in the non-exposed portion), and therefore the test could not be performed.

Industrial use possibility

The photo spacer formed by the photosensitive resin composition for photo spacer formation of the present invention has a large plastic deformation amount and is excellent in surface smoothness, and can be analyzed to a fine pattern of 3 to 50 μm , so that the release property is good. Suitable for residual patterns such as photo spacers.

The photosensitive resin composition for forming a photo spacer of the present invention can be used for forming a photo spacer used in a liquid crystal display device, and can be used for an insulating film (contact hole formation), an overcoat layer (planarization film), The formation of the forming material for liquid crystal alignment control. Further, it can be used as an adhesive for its subsequent use.

Claims (5)

A photosensitive resin composition for a photo spacer comprising a binder resin (A), a photopolymerizable compound (B), a photopolymerization initiator (C), and a solvent (D), characterized in that the photopolymerizable property The compound (B) is a compound containing the compound represented by the formula (I), and the content of the photopolymerizable compound (B) represented by the formula (I) is relative to the binder resin (A) and the photopolymerizable compound (B). And the total amount of the photopolymerization initiator (C) is 5 to 60% by mass, wherein the photopolymerization initiator (C) contains at least one selected from the group consisting of triazine, acetophenone compound, and double A compound of the group consisting of an imidazole compound, an anthracene compound, and a fluorenylphosphine oxide compound. In the formula (I), R ₁ to R ₆ each independently represent a hydrogen atom or a group of any one of the following formulas (I-1) to (I-3), and at least 4 of R ₁ to R ₆ The base of any of (I-1) to (I-3), the base of at least one of R ₁ to R ₆ is (I-2) or (I-3)] The composition of the first aspect of the patent application, wherein the content of the photopolymerizable compound (B) represented by the formula (I) is relative to the binder resin (A), the photopolymerizable compound (B), and the photopolymerization initiation. The total amount of the agent (C) is 20 to 40% by mass. The composition of claim 1 or 2, wherein the binder resin (A) is a resin obtained by copolymerizing at least two of the compounds (A2) to (A5); (A2); A4) a copolymerized unsaturated-bonded compound; (A3); a carboxylic acid having an unsaturated bond; (A4); a compound having an unsaturated bond and an epoxy group in one molecule; (A5); an acid anhydride However, (A2)~(A5) are different from each other. A photo spacer which is formed by using the composition according to any one of claims 1 to 3. A liquid crystal display device comprising the photo spacer according to item 4 of the patent application.