JP2016186609A - Photosensitive resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition having a good appearance during application, from which a high-definition spacer having excellent adhesiveness and elastic recovery property can be formed.SOLUTION: The photosensitive resin composition comprises, as essential components, a hydrophilic resin (A) having a radically polymerizable organic group, a polyfunctional (meth)acrylate (B), a photopolymerization initiator (C), a compound (D) having two or more hydrolyzable alkoxy groups, a fluorine-based surfactant (E), and a silicone-based surfactant (F).SELECTED DRAWING: None

Description

  The present invention relates to a photosensitive resin composition. Specifically, the present invention relates to a photosensitive resin composition for a photo spacer or a color filter protective film.

In recent liquid crystal display panels and the like, the size of a substrate has been increased, and a photosensitive resin composition is usually formed by a spin coating method in order to form a transparent film or pattern such as a coat layer on a substrate surface. The coating is formed by a slit & spin method or the like. On the other hand, from the viewpoint of improving productivity, supporting large screens, etc., a method for forming a high-quality uniform coating film while reducing the liquid content of the photosensitive resin composition solution has been studied.

From such a background, in order to form an excellent quality coating film, selection of a solvent type is being sought. For example, when a low boiling point solvent is used, the coating film is rapidly dried. On the other hand, at the time of evaporation of the solvent, the microbubbles contained in the coating film forming composition may be bumped. Such bumping causes bubbles to appear on the surface of the coating film, resulting in crater-like defects.
Therefore, conventionally, a high boiling point solvent has been used as a solvent. For example, a photosensitive resin composition containing a high-boiling solvent such as diethylene glycol ethyl methyl ether (boiling point 176 ° C.) and benzyl alcohol (boiling point 205 ° C.) has been proposed (for example, Patent Document 1).

JP 2007-25645 A

  An object of the present invention is to provide a photosensitive resin composition capable of forming a high-definition spacer with little surface unevenness during coating (high coating property) and excellent adhesion and elastic recovery characteristics.

The inventors of the present invention have reached the present invention as a result of studies to achieve the above object.
That is, the present invention has a hydrophilic resin (A) having a radical polymerizable organic group, a polyfunctional (meth) acrylate monomer (B), a photopolymerization initiator (C), and two or more hydrolyzable alkoxy groups. An alkali-developable photosensitive resin composition comprising a compound (D), a fluorine-based surfactant (E), and a silicone-based surfactant (F) as essential components; and these photosensitive resins A photo spacer and a color filter protective film formed on the liquid crystal display element by curing the composition.

  The photosensitive resin composition of the present invention is highly coatable and has the effect of being able to form a high-definition photospacer having excellent adhesion and elastic recovery characteristics.

The photosensitive resin composition capable of alkali development of the present invention comprises a hydrophilic resin (A) having a radical polymerizable organic group, a polyfunctional (meth) acrylate monomer (B), a photopolymerization initiator (C), two or more. A compound (D) having a hydrolyzable alkoxy group, a fluorine-based surfactant (E), and a silicone-based surfactant (F) are contained as essential components.

In this specification, “(meth) acrylate” means “acrylate or methacrylate”, “(meth) acrylic acid” means “acrylic acid or methacrylic acid”, and “(meth) acrylic resin” means “ “Acrylic resin or methacrylic resin”, “(meth) acryloyl group” means “acryloyl group or methacryloyl group”, and “(meth) acryloyloxy group” means “acryloyloxy group or methacryloyloxy group”.

  The term “alkaline developable” means that the uncured portion can be removed cleanly with an alkaline aqueous solution of the developer in the step of removing the uncured portion using a developer.

Below, (A)-(F) which is an essential structural component of the photosensitive resin composition of this invention is demonstrated in order.
The hydrophilicity index in the hydrophilic resin (A) having a radically polymerizable organic group, which is the first essential component in the present invention, is defined by HLB. Generally, the larger this value, the higher the hydrophilicity.
The HLB value of (A) is preferably 4 to 19, more preferably 5 to 18, and particularly preferably 6 to 17. When it is 4 or more, the developing property is further improved when developing the photospacer, and when it is 19 or less, the water resistance of the cured product is further improved.

Here, “HLB” is an index indicating a balance between hydrophilicity and lipophilicity, and is described in, for example, “Introduction to Surfactants” (published by Sanyo Chemical Industries, Ltd., 2007, Takehiko Fujimoto), page 212. It is known as the calculated value by the Oda method, not the calculated value by the Griffin method.
The HLB value can be calculated from the ratio between the organic value and the inorganic value of the organic compound.
The organic value and the inorganic value for deriving HLB = 10 × inorganic / organic HLB can be calculated by using the values in the table described in “Introduction of Surfactant” on page 213.

Further, the solubility parameter (hereinafter referred to as SP value) [(unit is (cal / cm ³ ) ^1/2 ]) of the hydrophilic resin (A) is preferably 7 to 14, more preferably 8 to 13, particularly preferably. Is from 9 to 13. If it is 7 or more, the developability can be further improved, and if it is 14 or less, the water resistance of the cured product is further improved.

The SP value in the present invention is calculated by the method described in the following document proposed by Fedors et al.
"POLYMER ENGINEERING AND SCIENCE, February, 1974, Vol. 14, No. 2, Robert F. Fedors (pp. 147-154)"
Those with close SP values are likely to mix with each other (highly dispersible), and those with a distant numerical value are difficult to mix.

  The hydrophilic resin (A) of the present invention has a radical polymerizable group contained in the molecule, and as the radical polymerizable organic group, from the viewpoint of photocurability, a (meth) acryloyl group, a vinyl group and an allyl group. Group is preferred, more preferably a (meth) acryloyl group.

  In addition, the functional group contributing to the hydrophilicity contained in the molecule of the hydrophilic resin (A) having a radical polymerizable organic group of the present invention is a carboxyl group, an epoxy group, a sulfonic acid group, from the viewpoint of alkali developability. A phosphoric acid group is preferable, and a carboxyl group is more preferable.

  Specific examples of the hydrophilic resin (A) that can be used in the present invention include a hydrophilic epoxy resin (A1) having a radical polymerizable organic group and a hydrophilic (meth) acrylic resin having a radical polymerizable organic group. (A2) etc. are mentioned.

As the hydrophilic epoxy resin (A1) having a radical polymerizable organic group of the present invention, a commercially available epoxy resin is reacted with a compound having a radical polymerizable organic group, and further a compound having a hydrophilic functional group is reacted. Can be synthesized.
For example, a novolac type epoxy resin having an epoxy group in the molecule is reacted with (meth) acrylic acid, and further reacted with a polyvalent carboxylic acid such as phthalic acid or phthalic anhydride, or a polyvalent carboxylic acid anhydride.

  The hydrophilic (meth) acrylic resin (A2) having a radically polymerizable organic group of the present invention is obtained by polymerizing a (meth) acrylic acid derivative by an existing method and further reacting with a compound having a radically polymerizable group. Can do.

  As a method for producing the hydrophilic (meth) acrylic resin (A2), radical polymerization is preferable, and a solution polymerization method is preferable because the molecular weight can be easily adjusted.

  Examples of the monomer used for producing the hydrophilic (meth) acrylic resin (A2) include (meth) acrylic acid (a21) and (meth) acrylic acid ester (a22).

  Examples of (a22) include methyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, hydroxyethyl (meth) acrylate, isobornyl (meth) acrylate, and preferably ( (Meth) methyl acrylate.

  As a monomer constituting the hydrophilic (meth) acrylic resin (A2), an aromatic ring-containing vinyl compound (a23) is used in combination with (a21) and (a22) from the viewpoint of elastic recovery characteristics of the photosensitive resin composition. May be. Examples of such (a23) include styrene.

  In the hydrophilic (meth) acrylic resin (A2), it is preferable to introduce a (meth) acryloyl group into a side chain or a terminal as necessary for the purpose of further improving the elastic recovery property of the photospacer.

  Examples of the method for introducing a (meth) acryloyl group into the side chain include the following methods (1) and (2).

(1) A polymer is produced using a monomer having a group capable of reacting with an isocyanate group (such as a hydroxyl group or a primary or secondary amino group) in at least a part of (a21) or (a22); A method of reacting a compound [(meth) acryloyloxyethyl isocyanate etc.] having a (meth) acryloyl group and an isocyanate group.

(2) A polymer using a monomer having a functional group capable of reacting with an epoxy group (hydroxyl group, carboxyl group, primary or secondary amino group, etc.) in at least a part of (a21) or (a22) A method of producing and then reacting a compound having a (meth) acryloyl group and an epoxy group (glycidyl (meth) acrylate, etc.)

The number average molecular weight of the hydrophilic resin (A) of the present invention is 1,000 to 100,000, preferably 3,000 to 50,000.

  Content of the hydrophilic resin (A) in the photosensitive resin composition of this invention is 10 to 80 weight% from the viewpoint of developability, based on the total weight of (A)-(D), Preferably 15- 70% by weight.

The polyfunctional (meth) acrylate monomer (B) which is the second essential component of the present invention is not particularly limited as long as it is a monomer having two or more (meth) acryloyl groups.
The number average molecular weight of the polyfunctional (meth) acrylate monomer (B) of the present invention is less than 1,000.
As such polyfunctional (meth) acrylate monomer (B), bifunctional (meth) acrylate (B1), trifunctional (meth) acrylate (B2), 4-6 functional (meth) acrylate (B3) and 7- A 10 functional (meth) acrylate (B4) is mentioned.

Examples of the bifunctional (meth) acrylate (B1) include esterified products of polyhydric alcohol and (meth) acrylic acid [for example, di (meth) acrylate of glycol, di (meth) acrylate of glycerin, dimethyl methacrylate). (Meth) acrylate, di (meth) acrylate of 3-hydroxy-1,5-pentanediol, di (meth) acrylate of 2-hydroxy-2-ethyl-1,3-propanediol]; alkylene oxide of polyhydric alcohol Adducts and esterified products of (meth) acrylic acid [for example, di (meth) acrylate of trimethylolpropane ethylene oxide adduct, di (meth) acrylate of glycerin ethylene oxide adduct]; OH group-containing both-end epoxy acrylate; Polyhydric alcohol and (meth) acryl Esters of acids and hydroxy carboxylic acids [e.g. hydroxypivalic acid neopentyl glycol di (meth) acrylate], and the like.
In addition, it is not necessary to make all the hydroxyl groups of a polyhydric alcohol react with (meth) acrylic acid, an alkylene oxide adduct, etc., and unreacted hydroxyl groups may remain.

Trifunctional (meth) acrylate (B2) includes tri (meth) acrylate of glycerin, tri (meth) acrylate of trimethylolpropane, tri (meth) acrylate of pentaerythritol; and trioxide of ethylene oxide adduct of trimethylolpropane. (Meth) acrylate etc. are mentioned.

Examples of tetra to hexafunctional (meth) acrylate (B3) include pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate; dipentaerythritol ethylene oxide addition Tetra (meth) acrylate of a product, penta (meth) acrylate of an ethylene oxide adduct of dipentaerythritol, penta (meth) acrylate of a propylene oxide adduct of dipentaerythritol, and the like.

  Examples of 7 to 10 functional (meth) acrylate compounds include a compound obtained by reaction of dipentaerythritol penta (meth) acrylate and hexamethylene diisocyanate, and the like by reaction of a diisocyanate compound with a hydroxyl group-containing polyfunctional (meth) acrylate compound. Can be obtained.

  The content of the polyfunctional (meth) acrylate monomer (B) in the photosensitive resin composition of the present invention is 10 to 80% by weight based on the total weight of (A) to (D) from the viewpoint of the elastic recovery rate. It is preferably 20 to 70% by weight.

As a photopolymerization initiator that is the third essential component of the present invention, a radical capable of initiating polymerization of a polymerizable unsaturated compound by exposure to radiation such as visible light, ultraviolet light, far infrared light, charged particle beam, and X-ray. Any component may be used as long as it is generated.

As the photopolymerization initiator (C), α-hydroxyalkylphenone type (C-1) (for example, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, etc.); α-aminoalkylphenone type (C-2) (for example, (2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1 -(4-morpholinophenyl) -butanone-1 etc.); thioxanthone compound type (C-3) (eg, (isopropylthioxanthone, diethylthioxanthone etc.); phosphate ester type (C-4) (eg, (2, 4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine Oxides); acyloxime type (C-5) (for example, 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)], ethanone, 1- [9- Ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime) etc.); benzyldimethyl ketal type (C-6) etc .; benzophenone type (C-7) (For example, benzophenone, 4-benzoyl-4′-methyldiphenyl sulfide, etc.).

  Of these, α-aminoalkylphenone is preferable from the viewpoint of curability of the cured product, and 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one is more preferable. 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1.

  The usage-amount of a photoinitiator (C) is 2 to 15 weight% from a viewpoint of sclerosis | hardenability and coloring of hardened | cured material based on the sum total of (A)-(D), Preferably it is 3 to 10 weight%.

Examples of the fourth essential component of the present invention include polysiloxanes having two or more hydrolyzable alkoxy groups.
Examples of the hydrolyzable alkoxy group include a methoxy group, an ethoxy group, a propoxy group, and a phenoxy group.

Among these, for the purpose of improving the elastic recovery property of the photospacer, an alkoxypolysiloxane represented by the following general formula (1) is preferable.

In the formula, (1) and R ¹ represent one or more organic groups selected from the group consisting of a (meth) acryloyloxyalkyl group, a glycidoxyalkyl group, a mercaptoalkyl group, and an aminoalkyl group.
R ² represents an aliphatic saturated hydrocarbon group, an alicyclic saturated hydrocarbon group, or an aromatic hydrocarbon group. R ³ represents an alkyl group having 1 to 4 carbon atoms.
m is 0 or 1.

Among R ² , examples of the aliphatic saturated hydrocarbon group include a linear alkyl group, a branched alkyl group, and an alicyclic saturated hydrocarbon group.
Linear alkyl groups include methyl, ethyl, n-propyl, n-butyl, n-octyl and n-dodecyl groups, branched alkyl groups such as isopropyl, isobutyl, sec-butyl and 2-ethylhexyl groups, and cyclic Examples of the saturated hydrocarbon group include a cyclohexyl group, a cyclooctyl group, a cyclohexylmethyl group, a cyclohexylethyl group, and a methylcyclohexyl group.

Among R ² , examples of the aromatic hydrocarbon group include an optionally substituted aryl group, aralkyl group, and alkylaryl group.
The aryl group is phenyl, biphenyl, naphthyl group and their respective fluorine or chlorine substituents; the aralkyl group is tolyl, xylyl, mesityl group and their fluorine or chloride; and the alkylaryl group is methylphenyl and ethyl A phenyl group etc. are mentioned.

R ² is preferably a linear alkyl group, a branched alkyl group and an aryl group from the viewpoint of curing reactivity, more preferably a linear alkyl group and an aryl group, particularly preferably a methyl group, an ethyl group and a phenyl group. And combinations thereof.

Examples of R ³ include an alkyl group having 1 to 20 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a sec-butyl group, and preferably a heat group. From the viewpoint of curing reactivity, a methyl group and an ethyl group.

In the general formula (1), examples of the silane compound having a (meth) acryloyloxyalkyl group as R ¹ include the following compounds.
Examples of the trifunctional silane compound in which m is 0, that is, three alkoxy groups include 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3- Examples include acryloyloxypropyltriethoxysilane.

Examples of the trifunctional silane compound in which m is 1, that is, two alkoxy groups include 3-methacryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, 3-acryloyloxypropylmethyldimethoxysilane, 3 -Acryloyloxypropylmethyldiethoxysilane and the like.

Examples of the silane compound having a glycidoxyalkyl group as R ¹ include the following compounds.
Examples of the trifunctional silane compound in which m is 0, that is, three alkoxy groups include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, etc.

As the trifunctional silane compound having m of 1, that is, two alkoxy groups, 3-glycidoxy. Examples include propylmethyldimethoxysilane and 3-glycidoxypropylmethyldiethoxysilane.

Examples of the silane compound having a mercaptoalkyl group as R ¹ include the following compounds.
Examples of the trifunctional silane compound in which m is 0, that is, three alkoxy groups include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and the like.

Examples of the trifunctional silane compound in which m is 1, that is, two alkoxy groups include 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, and the like.

Examples of the silane compound having an aminoalkyl group as R ¹ include the following compounds.
Examples of trifunctional silane compounds in which m is 0, that is, three alkoxy groups include N-2 aminoethyl γ-aminopropyltrimethoxysilane, N-2 aminoethyl γ-aminopropyltriethoxysilane, and 3-aminopropyltrimethoxy. Silane, 3-aminopropyltriethoxysilane, etc. are mentioned.

Examples of trifunctional silane compounds in which m is 1, that is, two alkoxy groups include N-2 aminoethyl γ-aminopropylmethyldimethoxysilane, N-2 aminoethyl γ-aminopropylmethyldiethoxysilane, and 3-aminopropylmethyl. Examples include dimethoxysilane and 3-aminopropylmethyldiethoxysilane.

Of the compounds (D), a (meth) acryloyloxyalkyl group-containing trifunctional silane compound having three alkoxy groups and a glycidoxyalkyl group-containing trifunctional silane compound having three alkoxy groups are preferable. More preferred are 3-acryloyloxypropyltrimethoxysilane and 3-glycidoxypropyltrimethoxysilane.

  The content of the polysiloxane compound (D) having two or more hydrolyzable alkoxy groups in the photosensitive resin composition of the present invention is the total of (A) to (D) from the viewpoint of elastic recovery and adhesion. Based on the weight, it is usually 0.2 to 15% by weight, preferably 0.5 to 12% by weight.

    Examples of the fluorine-based surfactant (E) that is the fifth essential component of the present invention include anion type (E1) (for example, carboxylate, phosphate) and nonionic type (E2) (oxygen such as ethylene oxide and propylene oxide). Compounds having an alkylene chain, and other hydrophilic group / lipophilic group-containing compounds).

  Of these, nonionic fluorine-based surfactant (E2) is preferable from the viewpoint of compatibility, and a compound having an oxyalkylene chain is more preferable.

  The amount of the fluorosurfactant (E) used is usually 0.1 to 5% by weight, preferably 0.5 to 3% by weight from the viewpoint of surface unevenness and compatibility based on the total of (A) to (D). %.

  The silicone-based surfactant (F) as the sixth essential component of the present invention includes amino-modified silicone surfactant (F1), silicone-based surfactant (F2) having an oxyalkylene chain, and epoxy group-modified silicone. Surfactants (F3), hydroxyl group-modified silicone surfactants (F4), mercapto group-modified silicone surfactants (F5), and the like.

  Among these, from the viewpoint of compatibility, a silicone surfactant (F2) having an oxyalkylene chain is preferable, and a compound having an oxyalkylene chain in the side chain is more preferable.

  The usage-amount of a silicone type surfactant (F) is 0.01-3 weight% normally from a surface nonuniformity and compatibility viewpoint based on the sum total of (A)-(D), Preferably it is 0.02-2 weight. %.

  Furthermore, the weight ratio of the content of the fluorosurfactant (E) and the content of the silicone surfactant (F) is usually 1 to 300, preferably 30 to 200. . If it is smaller than 1, the compatibility is poor, and if it is larger than 300, the surface unevenness becomes large.

The photosensitive resin composition according to the present invention may further contain other components as necessary. Other components include inorganic fine particles (eg, titanium oxide, alumina, etc.), sensitizers, polymerization inhibitors, solvents, thickeners, and other additives (eg, silane coupling agents, antioxidants, and Antifoaming agent).

  Hereinafter, although an example and a comparative example explain the present invention further, the present invention is not limited to these. Hereinafter, unless otherwise specified, “%” represents “% by weight” and “parts” represents “parts by weight”.

Production Example 1 [Production of hydrophilic vinyl resin (A-1)]
172 parts of propylene glycol monomethyl ether acetate was charged into a glass Kolben equipped with a heating / cooling / stirring device, a reflux condenser, a dropping funnel, and a nitrogen introduction tube, and heated to 90 ° C. A solution in which 177 parts of methacrylic acid, 13 parts of methyl methacrylate, 395 parts of styrene, and 207 parts of propylene glycol monomethyl ether acetate were uniformly mixed, and dimethyl-2,2′-azobis (2-methylpropionate) 5 Part of the solution and 12 parts of propylene glycol monomethyl ether acetate were added dropwise, and radical polymerization was performed in glass Kolben to obtain a reaction product.
The reaction product was further charged with 19 parts of glycidyl methacrylate, reacted at 90 ° C. for 5 hours, and then diluted with propylene glycol monomethyl ether acetate so that the hydrophilic resin content was 50% by weight. A 50% propylene glycol monomethyl ether acetate solution of the resin (A-1) was obtained.
The acid value in terms of pure content of this resin was 100.2. The number average molecular weight (Mn) by GPC was 5,800. The SP value was 10.5 and the HLB value was 5.8.

Production Example 2 [Production of hydrophilic epoxy resin (A-2)]
A glass Kolben equipped with a heating / cooling / stirring device, a reflux condenser, a dropping funnel and a nitrogen introduction tube, cresol novolac type epoxy resin “EOCN-102S” (Epoxy equivalent 200 from Nippon Kayaku Co., Ltd.) and propylene 245 parts of glycol monomethyl ether acetate was charged and heated to 110 ° C. to dissolve uniformly. Subsequently, 76 parts of acrylic acid (1.07 mol part), 2 parts of triphenylphosphine and 0.2 part of p-methoxyphenol were charged and reacted at 110 ° C. for 10 hours.
The reaction product was further charged with 91 parts (0.60 mole part) of tetrahydrophthalic anhydride, reacted at 90 ° C. for 5 hours, and then the hydrophilic resin content was adjusted to 50% by weight with propylene glycol monomethyl ether acetate. Dilution was performed to obtain a 50% propylene glycol monomethyl ether acetate solution of a carboxyl group-containing cresol novolac epoxy resin (A-1) as a hydrophilic resin having an acryloyl group and a carboxyl group of the present invention.
The acid value in terms of pure content of this resin was 88.4. The number average molecular weight (Mn) by GPC was 2,200. The SP value was 11.3 and the HLB value was 6.4.

Production Example 3 [Production of hydrolyzable alkoxy group-containing polysiloxane compound (D-1)] To a glass Kolben equipped with a heating / cooling / stirring device, a reflux condenser, a dropping funnel and a nitrogen introducing pipe, 3-acryloyl Roxypropyltrimethoxysilane 46 parts (0.2 mol part), diphenyldimethoxysilane 160 parts (0.65 mol part), ion-exchanged water 45 g (2.5 mol parts), and oxalic acid 0.1 part (0. 001 mol part), and heated and stirred at 60 ° C. for 6 hours. Further, by using an evaporator, methanol produced as a by-product by hydrolysis was removed under reduced pressure over 2 hours to obtain an acrylic-modified alkoxypolysiloxane (D -1) (Mn: 2,100) was obtained.

Example 1
According to the number of parts (parts by weight) in Table 1, a 50% propylene glycol monomethyl ether acetate solution of the hydrophilic vinyl resin (A-1) produced in Production Example 1 in a glass container, (B-1), (C- 1), (E-1), (F-1) Further, the acrylic-modified alkoxypolysiloxane compound (D-1) produced in Production Example 3 was charged, stirred until uniform, and an additional solvent (propylene glycol monomethyl) Ether acetate) was added to obtain a photosensitive resin composition of Example 1.

Examples 2-5 and Comparative Examples 1-3
Moreover, the photosensitive resin composition of Examples 2-5 and Comparative Examples 1-3 was obtained by the mixing | blending part number of Table 1 using the same apparatus. In addition, in the case of a solution, the weight part of Table 1 is a pure part conversion.

The details of the abbreviated chemicals in Table 1 are as follows.
(B-1): “Neomer DA-600” (dipentaerythritol pentaacrylate: Sanyo Chemical Industries, Ltd .; 6 functional groups)
(B-2): “Neomer EA-300” (pentaerythritol tetraacrylate: Sanyo Chemical Industries, Ltd .; 4 functional groups)
(C-1): “Irgacure 819” (bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide: manufactured by BASF Corp.))
(C-2): “Irgacure 907” (2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one: manufactured by BASF Corporation)
(C-3): “Kayacure DETX-S” (2,4-diethylthioxanthone: manufactured by Nippon Kayaku Co., Ltd.)
(D-2): “KR-513” (acryl-modified methoxypolysiloxane: manufactured by Shin-Etsu Chemical Co., Ltd.)
(E-1): “Surflon S-386” (fluorine compound having an oxyalkylene chain: manufactured by AGC Seimi Chemical Co., Ltd.)
(E-2): “Megafac TF-2066” (fluorine compound having an oxyalkylene chain: manufactured by DIC Corporation)
(F-1): “KF-352A” (polydimethylsiloxane having an oxyalkylene chain: manufactured by Shin-Etsu Chemical Co., Ltd.)
(F-2): “BYK-377” (hydroxyl group-containing polydimethylsiloxane having an oxyalkylene chain: manufactured by Big Chemie Japan Co., Ltd.)

Hereinafter, a method for evaluating the performance of surface unevenness (high applicability), adhesion, and elastic recovery during application will be described.

<Evaluation of high coatability>
[Creation of substrate for coating unevenness observation]
A 10 cm × 10 cm square glass substrate was coated with a spin coater and dried to form a coating film having a dry film thickness of 5 μm. This coating film was heated on a hot plate at 80 ° C. for 3 minutes.
The obtained coating film was irradiated with 60 mJ / cm ² of light from an ultrahigh pressure mercury lamp (illuminance 22 mW / cm ^{2 in} terms of i-line) to prepare a substrate for coating unevenness observation.

[Determination of high coatability]
The board | substrate created above was illuminated with the sodium lamp, and the coating surface was confirmed visually.
When the coating unevenness was clearly confirmed, it was evaluated as x, when it was slightly confirmed, and when it was hardly confirmed, it was evaluated as ◯.

[Production of photo spacer]
A 10 cm × 10 cm square glass substrate was coated with a spin coater and dried to form a coating film having a dry film thickness of 5 μm. This coating film was heated on a hot plate at 80 ° C. for 3 minutes.
The obtained coating film was irradiated with light of an ultrahigh pressure mercury lamp at 60 mJ / cm ² through a plurality of masks for forming a photospacer having 10,000 openings per cm ² and diameters of 7, 8, 9 and 10 μm (i Illuminance 22 mW / cm ^{2 in} line conversion).
In addition, it exposed with the space | interval (exposure gap) of a mask and a board | substrate 100 micrometers.
Thereafter, alkali development was performed using a 0.05% aqueous KOH solution. After washing with water, post-baking was performed at 230 ° C. for 30 minutes to form 10,000 photospacers per 1 cm ² on the glass substrate.
Note that a photo spacer having a desired lower base diameter can be formed by adjusting the mask opening diameter.

<Evaluation of adhesion>
With the miniaturization and high definition of the LCD, the size of the photo spacer manufactured on the substrate is required to be 10 μm or less. However, the smaller the ground contact area between the substrate and the photo spacer, the higher the adhesion is required.
In other words, a photo spacer with higher adhesion is more excellent in performance that is less likely to be peeled off by rubbing or the like even if the lower bottom diameter of the spacer is smaller.
Therefore, the adhesiveness was evaluated by setting the bottom bottom diameter of the spacer to 8 μm in diameter and performing the following swab rubbing test.

Select only a mask having a bottom base diameter of 8 μm from the photo spacers prepared using a plurality of masks for forming photo spacers having openings with diameters of 7, 8, 9 and 10 μm, and have the following adhesion properties: A test was conducted.
(1) A cross mark of 1 cm in length and 1 cm in width is marked with an oil-based pen on the back side of the glass substrate on which the photo spacer is formed.
(2) First, rubbing the surface of the front side of the glass substrate marked with a cross with a cotton swab soaked with acetone 10 times from the top of the vertical line downward at a speed of 2 cm per second.
Next, rubbing 10 times from the left of the horizontal line to the right at a speed of 2 cm per second.
(3) Count the number of remaining photospacers without peeling off the point where the rubbed portions in (2) intersect with an optical microscope.
In the case where no peeling occurs, there are 100 (10 × 10) spacers per mm ² on the glass substrate.

<Evaluation of elastic recovery characteristics>
The elastic recovery characteristic of the photospacer can be evaluated by an “elastic recovery rate” when a certain pressure defined by the following formula (1) is applied.
The higher the elastic recovery rate (%), the better the elastic recovery characteristics.
Generally, 70% or more is required.
The elastic recovery characteristic this time was evaluated by measuring the elastic recovery rate under a pressure condition of 0.25 mN / μm ² .

(1) A micro hardness tester (Fischer Instruments, Inc .; “Fischer Scope H-100”) and a planar indenter having a square cross section for one photo spacer selected arbitrarily from among photo spacers formed on a glass substrate. (50 μm × 50 μm) was used to measure the amount of deformation when a load was applied and when the load was returned.
At this time, the load was applied to 60 mN over 30 seconds at a load speed of 2 mN / second and held for 5 seconds.
The amount of deformation from the initial position of the photospacer in a state where a load was applied was measured. The amount of change at this time is defined as a total deformation amount T ₀ (μm).
(2) Next, the load was released to 0 over 30 seconds at an unloading speed of 2 mN / second, and the state was maintained for 5 seconds. The deformation amount of the photo spacer at this time is defined as a plastic deformation amount T ₁ (μm).
(3) From the total deformation amount T ₀ and the plastic deformation amount T ₁ measured as described above, the elastic recovery rate was calculated using the following mathematical formula (1).

Elastic recovery rate (%) = [(T ₀ −T ₁ ) / T ₀ ] × 100 (1)

As shown in Table 1, the photosensitive resin compositions of Examples 1 to 5 of the present invention are excellent in all aspects of surface unevenness during coating, (high coating property) adhesion, and elastic recovery rate.
On the other hand, Comparative Example 1 which does not include the compound having an alkoxy group of the present invention does not satisfy the elastic recovery rate and the adhesiveness. Further, in Comparative Example 2 in which no fluorosurfactant is added and in Comparative Example 3 in which no silicone surfactant is added, surface unevenness is deteriorated.

  Since the photosensitive resin composition of the present invention is excellent in elastic recovery characteristics after curing and adhesion to a glass substrate, it can be suitably used as a photo spacer for display elements or a protective film for color filters. In addition, resist for forming an insulating film for touch panel, and other various resist materials, such as photo solder resist, photosensitive resist film, photosensitive resin relief plate, screen plate, photoadhesive or hard coat material, etc. It is suitable as a resin composition.

Claims (11)

Hydrophilic resin (A) having radically polymerizable organic group, polyfunctional (meth) acrylate (B), photopolymerization initiator (C), compound having two or more hydrolyzable alkoxy groups (D), fluorine-based A photosensitive resin composition capable of alkali development, which comprises a surfactant (E) and a silicone surfactant (F) as essential components. 2. The content of (E) is 0.1 to 5% by weight and the content of (F) is 0.01 to 3% by weight based on the total weight of (A) to (D). The photosensitive resin composition as described. The photosensitive resin composition according to claim 1 or 2, wherein the weight ratio (E) / (F) of the contents of (E) and (F) is 1 to 300. The photosensitive resin composition according to claim 1, wherein the fluorine-based surfactant (E) is a compound having an oxyalkylene chain. The photosensitive resin composition according to claim 1, wherein the silicone-based surfactant (F) is a compound having an oxyalkylene chain. The photosensitive resin composition according to claim 1, wherein the compound (D) having two or more hydrolyzable alkoxy groups is polysiloxane.   The photosensitive resin composition according to any one of claims 1 to 6, wherein the hydrophilic resin (A) has an HLB of 4 to 19.   Based on the total amount of (A) to (D), the hydrophilic resin (A) is 10 to 80% by weight, the polyfunctional (meth) acrylate (B) is 10 to 80% by weight, and the photopolymerization initiator (C). The photosensitive resin composition according to any one of claims 1 to 7, which comprises 2 to 15% by weight of the compound (D) having 2 to 15% by weight and 2 or more hydrolyzable alkoxy groups.   A photo spacer formed by subjecting the photosensitive resin composition according to claim 1 to light development, followed by alkali development to form a pattern, and further post-baking.   A protective film for a color filter, which is formed by subjecting the photosensitive resin composition according to claim 1 to light development, followed by alkali development to form a pattern, and further post-baking.   A protective film or an insulating film for a touch panel, which is formed by subjecting the photosensitive resin composition according to claim 1 to light development, followed by alkali development to form a pattern, and further post-baking. film.