JP6275366B2 - Photosensitive aqueous epoxy resin curing fine particles, photosensitive aqueous epoxy resin curing fine particle production method, and photosensitive aqueous epoxy resin composition - Google Patents

Description

The present invention relates to fine particles for curing an epoxy resin that, when blended in a photosensitive aqueous epoxy resin composition, has excellent dispersibility and can improve curing efficiency. The present invention also relates to a method for producing the epoxy resin curing fine particles and a photosensitive aqueous epoxy resin composition containing the epoxy resin curing fine particles.

A photosensitive resin composition containing an oligomer or polymer as a main component is used in a wide range of fields such as photo patterning technology. The photosensitive resin composition allows a wide range of photosensitive wavelength regions to be set, and is manufactured at a relatively low cost. However, the photosensitive speed (curing speed) is extremely low as compared with the silver salt photosensitive material, and the sensitivity of even the most sensitive polymer photosensitive resin composition does not reach 1/1000 of that of the silver salt photosensitive material.

As a photosensitive resin composition, a resin composition that is cured by cationic polymerization has attracted attention. In cationic polymerization, unlike radical polymerization, there is no inhibition effect due to oxygen in the air, and in the case of ring-opening polymerization reaction such as epoxy group, volume shrinkage during curing is very small, and stress strain is reduced. . Among them, the epoxy resin composition has good adhesion and adhesion to the substrate surface due to the polarity of the oxygen atom derived from the epoxy group, and can give a cured film excellent in flexibility. Furthermore, the characteristics of the cured film can be further improved by heat treatment at the time of active energy ray irradiation or after irradiation.

Epoxy resin compositions often contain a base such as an amine as a curing agent, and research has been conducted on a photobase generator that generates a base by irradiating active energy rays to express a catalytic activity ( For example, Patent Document 1). However, when an amine is used as a curing agent, the curing mechanism is a sequential addition reaction between an amine and an epoxy group, so that the curing rate is low and it takes time to obtain a highly reliable cured product. Therefore, it is desirable to utilize an acid catalyzed reaction in order to achieve faster curing.
So far, a photosensitive resin composition using an acid-catalyzed reaction in which a photoacid generator that generates an acid by irradiation with active energy rays has been studied. However, although attempts have been made to improve the curing efficiency such as improving the quantum yield of the photoacid generator and improving the acid catalyst reaction rate, there has been a limit to improving the curing efficiency.

On the other hand, in recent years, water-based epoxy resins that have low environmental impact and high work safety are attracting attention due to environmental problems or increasing social demands for safety.
However, conventional photobase generators, photoacid generators and the like are oil-soluble, have low solubility in water-based epoxy resins, and are poorly dispersible. Is difficult to form. Moreover, if an organic solvent is used to dissolve the photobase generator, photoacid generator, etc., the intended use of the water-based epoxy resin, such as reduction of environmental burden or ensuring safety, cannot be achieved sufficiently. Accordingly, there is a need for a new epoxy resin curing agent that can handle water-based epoxy resins.

JP 2006-328427 A

An object of this invention is to provide the fine particle for epoxy resin hardening which is excellent in a dispersibility and can improve hardening efficiency, when it mix | blends with the photosensitive aqueous epoxy resin composition. Another object of the present invention is to provide a method for producing the epoxy resin curing fine particles and a photosensitive aqueous epoxy resin composition containing the epoxy resin curing fine particles.

The present invention is an epoxy resin curing fine particle having a group that causes an acid proliferation reaction on its surface, and is radically polymerizable mainly in a water-based medium having a monomer having a structure represented by the following general formula (1) It is the fine particle for epoxy resin hardening obtained by polymerizing a monomer.

一般式（１）中、Ｘは水素原子又はメチル基を表し、Ａは酸増殖反応を引き起こす基を表す。以下、本発明を詳述する。

In general formula (1), X represents a hydrogen atom or a methyl group, and A represents a group that causes an acid proliferation reaction. The present invention is described in detail below.

In order to improve the curing efficiency of the photosensitive resin composition, the present inventor has studied to accelerate the acid catalyzed reaction using an acid multiplication reaction. The acid growth reaction is a photoacid generator that generates an acid by irradiation with active energy rays, and a thermal acid generator that generates an acid by the catalytic action of the acid generated from the photoacid generator (referred to as an acid growth agent). When used in combination, it refers to a reaction in which an acid proliferates autocatalytically upon irradiation with active energy rays. That is, if one acid molecule generated from the photoacid generator can decompose one acid proliferator molecule and generate one new acid molecule, one acid molecule grows in one reaction. A total of two acid molecules. If this reaction occurs in a chain, the acid molecule will increase to the mouse formula.
As a result of the study, the present inventor has been able to radically polymerize a monomer having a group that causes an acid proliferation reaction, thereby being suitably used as an acid proliferation agent and dramatically improving the curing efficiency when blended in a photosensitive epoxy resin composition. It was found that fine particles for curing an epoxy resin can be obtained. Since such epoxy resin curing fine particles can dramatically improve the curing efficiency, they can be applied to a wide range of epoxy resins. Further, the present inventor has found that fine particles for curing an epoxy resin excellent in dispersibility with respect to an aqueous epoxy resin can be obtained by performing radical polymerization in an aqueous medium, and the present invention has been completed.

The fine particles for curing an epoxy resin of the present invention have a group that causes an acid proliferation reaction on the surface.
In the present specification, a group that causes an acid proliferation reaction is a group that decomposes when heated in the presence of an acid generated from a photoacid generator that generates acid by irradiation with active energy rays, and newly generates an acid. Say. By having the group that causes the acid proliferation reaction, the epoxy resin curing fine particles of the present invention are suitably used as an acid proliferation agent, and dramatically improve the curing efficiency when blended in a photosensitive aqueous epoxy resin composition. be able to. In addition, since the group causing the acid proliferation reaction is decomposed only by the action of an acid generated from a photoacid generator that generates an acid by irradiation with active energy rays, the epoxy resin curing fine particles of the present invention are photosensitive aqueous systems. The storage stability of the epoxy resin composition is not lowered.

The group causing the acid proliferation reaction is decomposed when heated to a temperature of 100 to 140 ° C., for example, in the presence of an acid generated from a photoacid generator that generates an acid upon irradiation with active energy rays. Is preferably generated. Examples of active energy rays for generating an acid from the photoacid generator include light such as infrared rays, visible rays, and ultraviolet rays, radiation such as X-rays and γ rays, ion beams, and the like.

The group that causes the acid proliferation reaction is not particularly limited, but preferably has a structure that causes an acid proliferation reaction represented by the following general formula (2) or (3).

一般式（２）及び（３）中、Ｒ^１は芳香族基又は脂肪族基を表し、ｎは整数を表す。ｎは１〜２０の整数であることが好ましく、２〜１０の整数であることがより好ましい。

In general formulas (2) and (3), R ¹ represents an aromatic group or an aliphatic group, and n represents an integer. n is preferably an integer of 1 to 20, and more preferably an integer of 2 to 10.

The aromatic group may be a group having a carbocyclic ring as an aromatic ring or a group having a heterocyclic ring.
Examples of the carbocycle include a monocyclic ring such as a benzene ring, a condensed polycyclic ring such as a naphthalene ring, a pyrene ring, an azulene ring, a fluorene ring, an anthracene ring, and a chrysene ring; A ring etc. are mentioned. The group having a heterocycle is a heteroaromatic group containing at least one heteroatom such as a nitrogen atom, an oxygen atom, or a sulfur atom. The heterocycle preferably has 4 to 20 ring atoms, more preferably 5 to 10 and specifically includes a thiophene ring, a benzothiophene ring, a furan ring, a benzofuran ring, and the like. It is done.

In the aromatic group, one or more substituents may be bonded to the aromatic ring. Examples of such a substituent include a halogen atom, an alkyl group having 1 to 6 carbon atoms, a nitro group, and a cyano group.

The aliphatic group preferably has 1 to 20 carbon atoms, and more preferably 1 to 10 carbon atoms. The aliphatic group may be a chain aliphatic group or a cyclic aliphatic group.
Examples of the chain aliphatic group include an alkyl group and an alkenyl group, an alkyl group having 1 to 20 carbon atoms is preferable, and an alkyl group having 1 to 4 carbon atoms is more preferable. Examples of the cycloaliphatic group include a cycloalkyl group having 5 to 20 carbon atoms, preferably 6 to 10 carbon atoms, and a bicycloalkyl group.

The aliphatic group may have a substituent. Examples of such a substituent include a halogen atom.

The fine particles for curing an epoxy resin of the present invention can be obtained by polymerizing a radical polymerizable monomer whose main component is a monomer having a structure represented by the following general formula (1) in an aqueous medium.

一般式（１）中、Ｘは水素原子又はメチル基を表し、Ａは酸増殖反応を引き起こす基を表す。

In general formula (1), X represents a hydrogen atom or a methyl group, and A represents a group that causes an acid proliferation reaction.

The monomer having the structure represented by the general formula (1) is not particularly limited, and examples thereof include a monomer having a structure that causes an acid proliferation reaction represented by the general formula (2) or (3).
Examples of the monomer having a structure that causes an acid proliferation reaction represented by the general formula (2) include monomers having a structure represented by the following formulas (2-1) to (2-9). Examples of the monomer having a structure that causes an acid proliferation reaction represented by the general formula (3) include monomers having a structure represented by the following formulas (3-1) to (3-9).

The radical polymerizable monomer is not particularly limited as long as the monomer having the structure represented by the general formula (1) is a main component, and other radical polymerizable monomers, emulsifiers, and water-soluble polymers as necessary. Further, it may contain a dispersant and the like.
The other radical polymerizable monomer is not particularly limited, and examples thereof include a carboxyl group-containing monomer, a nitrile monomer, an acrylic ester monomer, a methacrylic ester monomer, and a vinyl monomer. Among these other radical polymerizable monomers, hydrophilic monomers such as carboxyl group-containing monomers are preferable.

The carboxyl group-containing monomer is not particularly limited, and examples thereof include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, ethacrylic acid, crotonic acid, and cinnamic acid, maleic acid, itaconic acid, fumaric acid, citraconic acid, and the like. Saturated dicarboxylic acid etc. are mentioned.
The nitrile monomer is not particularly limited, and examples thereof include acrylonitrile and methacrylonitrile.
The acrylate monomer is not particularly limited, and examples thereof include methyl acrylate, ethyl acrylate, butyl acrylate, and dicyclopentenyl acrylate.
The methacrylic acid ester monomer is not particularly limited, and examples thereof include methyl methacrylate, ethyl methacrylate, butyl methacrylate, and isobornyl methacrylate.
The vinyl monomer is not particularly limited, and examples thereof include vinyl chloride, vinylidene chloride, vinyl acetate, styrene, and divinylbenzene.

The blending amount of the other radical polymerizable monomer is not particularly limited, but a preferable upper limit with respect to 100 parts by weight of the monomer having the structure represented by the general formula (1) as a main component is 50 parts by weight. When the blending amount of the other radical polymerizable monomer exceeds 50 parts by weight, the resulting epoxy resin curing fine particles have a small number of groups that cause an acid proliferation reaction on the surface and cannot function as an acid proliferation agent. is there.

The emulsifier is not particularly limited, and examples thereof include alkyl sulfate sulfonate, alkyl benzene sulfonate, alkyl sulfate triethanolamine, polyoxyethylene alkyl ether, and polyvinyl alcohol.
Although the compounding quantity of the said emulsifier is not specifically limited, The preferable minimum with respect to 100 weight part of said radically polymerizable monomers is 0.01 weight part, and a preferable upper limit is 10 weight part. If the amount of the emulsifier is less than 0.01 parts by weight, the particle diameter of the resulting epoxy resin curing fine particles may not be sufficiently reduced, and the formed epoxy resin curing fine particles may aggregate. May end up. When the amount of the emulsifier exceeds 10 parts by weight, the particle purity of the resulting epoxy resin curing fine particles may be lowered.

The water-soluble polymer is not particularly limited. For example, polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), polyethylene oxide, gum arabic, gelatin, glycerin, alkyl cellulose, hydroxy-alkyl cellulose, carboxyalkyl cellulose, polyacrylamide, Examples include polyacrylic acid and polymethacrylic acid.
A blending amount of the water-soluble polymer is not particularly limited, but a preferable lower limit with respect to 100 parts by weight of the radical polymerizable monomer is 0.001 part by weight, and a preferable upper limit is 5 parts by weight. When the blending amount of the water-soluble polymer is less than 0.001 part by weight, the dispersion stabilizing effect by using the water-soluble polymer may not be sufficiently obtained. When the amount of the water-soluble polymer exceeds 5 parts by weight, the water-soluble polymer adsorbed on the surface of the resulting epoxy resin curing fine particles or the non-adsorbed water-soluble polymer may cause cross-linking aggregation. .

As said dispersing agent, inorganic powder etc. are mentioned, for example.
The blending amount of the dispersant is not particularly limited, but a preferable lower limit with respect to 100 parts by weight of the radical polymerizable monomer is 0.001 part by weight, and a preferable upper limit is 5 parts by weight.

The aqueous medium is not particularly limited as long as it is an aqueous medium usually used for polymerizing a radical polymerizable monomer, and examples thereof include water, alcohol, a mixture of water and alcohol, and the like. Examples of the alcohol include methanol, ethanol, propanol, isopropanol, t-butanol, and the like.

The polymerization method is not particularly limited, and examples thereof include a polymerization method by emulsion polymerization, suspension polymerization, dispersion polymerization, soap-free polymerization and the like.

When the emulsion polymerization or the suspension polymerization is used, the epoxy resin curing fine particles of the present invention are obtained, for example, as follows.
To the aqueous medium, the radical polymerizable monomer, the polymerization initiator, and the emulsifier or the water-soluble polymer are added, and oil droplets containing the radical polymerizable monomer are dispersed in the aqueous medium. The radical polymerizable monomer is polymerized to obtain fine particles for curing the epoxy resin of the present invention. In order to disperse the oil droplets in the aqueous medium, generally an emulsifier is used in emulsion polymerization, and a water-soluble polymer and / or a dispersant is used in suspension polymerization.
In the emulsion polymerization and the suspension polymerization, a polymerization initiator may be added to the aqueous medium together with the radical polymerizable monomer and the like, and after the radical polymerizable monomer and the like are added to the aqueous medium in advance. When the radical polymerizable monomer is polymerized, it may be added to the aqueous medium. In the emulsion polymerization, the polymerization initiator is hydrophilic, and in the suspension polymerization, the polymerization initiator is lipophilic.

When the dispersion polymerization is used, the epoxy resin curing fine particles of the present invention are obtained, for example, as follows.
In the aqueous medium, the radical polymerizable monomer, the hydrophilic or lipophilic polymerization initiator, and the water-soluble polymer and / or the emulsifier are dissolved, and then the radical polymerizable monomer is polymerized to obtain a polymer. Precipitate. The polymer is agglomerated in the aqueous medium to form particles, whereby the epoxy resin curing fine particles of the present invention are obtained.

When using the soap-free polymerization, the epoxy resin curing fine particles of the present invention are obtained, for example, as follows.
The radical polymerizable monomer and the hydrophilic polymerization initiator are added to the aqueous medium, and oil droplets containing the radical polymerizable monomer are dispersed in the aqueous medium, and then dissolved in the aqueous medium. The above radical polymerizable monomers are sequentially polymerized to precipitate a polymer. The polymer is agglomerated in the aqueous medium to form particles, whereby the epoxy resin curing fine particles of the present invention are obtained.

The lipophilic polymerization initiator is not particularly limited, and examples thereof include peroxides and azo compounds. The lipophilic peroxide is not particularly limited, and examples thereof include benzoyl peroxide, diisopropyl peroxycarbonate, dioctyl peroxydicarbonate, t-butyl peroxylaurate, lauroyl peroxide, dioctanoyl peroxide and the like. .
The lipophilic azo compound is not particularly limited. For example, azobisisobutyronitrile, azobis (2,4-dimethylvaleronitrile), 1,1-azobis (cyclohexane-1-carbonitrile), dimethyl 2,2- And azobis (2-methylpropionate).
These polymerization initiators may be used independently and 2 or more types may be used together.

Moreover, you may use radical photopolymerization initiators, such as AIBN and Irgacure819, as said lipophilic polymerization initiator.

Examples of the hydrophilic polymerization initiator include peroxides and azo compounds. The hydrophilic peroxide is not particularly limited. For example, hydrogen peroxide, acetyl peroxide, cumyl peroxide, t-butyl peroxide, propionyl peroxide, benzoyl peroxide, chlorobenzoyl peroxide, dichlorobenzoyl peroxide, Bromomethylbenzoyl peroxide, lauroyl peroxide, ammonium persulfate, sodium persulfate, potassium persulfate, diisopropyl peroxycarbonate, tetralin hydroperoxide, 1-phenyl-2-methylpropyl-1-hydroperoxide, t-butyl perphenylacetate Hydroperoxide, t-butyl performate, t-butyl peracetate, t-butyl perbenzoate, t-butyl perphenylacetate, t-butyl permethoxyacetate, t-butyl per-N- (3-toluyl) carbamate, Examples thereof include ammonium bisulfate and sodium bisulfate.
The hydrophilic azo compound is not particularly limited. For example, 2,2′-azobis (2-amidinopropane), 2,2′-azobis (N, N′-dimethyleneisobutylamidine), 2,2′-azobis [2- (5-Methyl-2-imidazolin-2-yl) propane], 1,1′-azobis (1-amidino-1-cyclopropylethane), 2,2′-azobis (2-amidino-4- Methylpentane), 2,2′-azobis (2-N-phenylaminoamidinopropane), 2,2′-azobis (1-imino-1-ethylamino-2-methylpropane), 2,2′-azobis ( 1-allylamino-1-imino-2-methylbutane), 2,2′-azobis (2-N-cyclohexylamidinopropane), 2,2′-azobis (2-N-benzylamidinopropane) and its hydrochloric acid, 4,4′-azobis (4-cyanovaleric acid) and its alkali metal salts, ammonium salts, amine salts, etc., 2- (carbamoylazo) isobutyronitrile, 2,2′-azobis ( Isobutylamide), 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2′-azobis [2-methyl-N- (1,1′-bis (hydroxymethyl) ) Ethyl) propionamide], 2,2′-azobis [2-methyl-N-1,1′-bis (hydroxyethyl) propionamide], 2,2′-azobis [N- (2-carboxyethyl)- 2-methylpropionamide] and the like.
These polymerization initiators may be used independently and 2 or more types may be used together.

Since the epoxy resin curing fine particles of the present invention are obtained by polymerizing a radically polymerizable monomer whose main component is a monomer having a structure represented by the general formula (1) in an aqueous medium as described above, The hydrophilicity of the surface is so high that it can be uniformly dispersed in the water-based epoxy resin, and it can be uniformly dispersed in the water-based epoxy resin, forming a uniform cured product, and improving the reliability of the cured product. Can be increased.
The reason why the hydrophilicity of the surface of the epoxy resin curing fine particles is increased in this way is, for example, that the emulsifier, the water-soluble polymer or the dispersant is adsorbed on the surface of the epoxy resin curing fine particles. . In addition, for example, when the dispersion polymerization or the soap-free polymerization is used and the radical polymerizable monomer contains the hydrophilic monomer, the precipitated polymer aggregates with the hydrophilic group facing outward, etc. Also mentioned.

The epoxy resin curing fine particles of the present invention are groups obtained by polymerizing a radically polymerizable monomer whose main component is a monomer having a structure represented by the general formula (1), thereby causing an acid proliferation reaction on the surface. It can be suitably used as an acid proliferating agent, and when blended in a photosensitive aqueous epoxy resin composition, the curing efficiency can be dramatically improved.
The epoxy resin curing fine particles of the present invention preferably have a segment derived from a monomer having a structure represented by the general formula (1). Furthermore, it is more preferable that the epoxy resin curing fine particles of the present invention have a segment derived from the monomer having the structure represented by the general formula (1) and a segment derived from the hydrophilic monomer. Thereby, the hydrophilic property of the surface is increased, and the dispersibility with respect to the water-based epoxy resin is further improved.

The volume average particle diameter of the epoxy resin curing fine particles of the present invention is not particularly limited, but a preferable lower limit is 0.03 μm and a preferable upper limit is 0.5 μm. When the volume average particle diameter of the epoxy resin curing fine particles of the present invention is less than 0.03 μm, the epoxy resin curing fine particles may easily aggregate. When the volume average particle diameter of the epoxy resin curing fine particles of the present invention exceeds 0.5 μm, the epoxy resin curing fine particles may block the active energy rays and may not be sufficiently cured. The more preferable lower limit of the volume average particle diameter of the epoxy resin curing fine particles of the present invention is 0.05 μm, and the more preferable upper limit is 0.3 μm.

In the present specification, the volume average particle size of the epoxy resin curing fine particles means a value measured by a dynamic light scattering particle size distribution analyzer (manufactured by Particle Sizing Systems, "NICOMP model 380 ZLS-S"). .

The use of the epoxy resin curing fine particles of the present invention is not particularly limited, but as described above, it is preferably blended in the photosensitive epoxy resin composition as an acid proliferating agent. Moreover, since the epoxy resin curing fine particles of the present invention are excellent in dispersibility with respect to the aqueous epoxy resin, it is more preferable to be blended in the photosensitive aqueous epoxy resin composition. As described above, the epoxy resin curing fine particles of the present invention are excellent in dispersibility with respect to the aqueous epoxy resin because the epoxy resin curing fine particles of the present invention are represented by the general formula (1) in the aqueous medium. This is because it is obtained by polymerizing a radically polymerizable monomer whose main component is a monomer having the structure represented.

A method for producing fine particles for curing an epoxy resin having a group that causes an acid proliferation reaction on the surface thereof, which is a radically polymerizable monomer comprising, as a main component, a monomer having a structure represented by the general formula (1) in an aqueous medium A method for producing epoxy resin curing fine particles by polymerizing is also one aspect of the present invention.

A photosensitive aqueous epoxy resin composition containing an aqueous epoxy resin, a photoacid generator, and fine particles for curing an epoxy resin of the present invention is also one aspect of the present invention.
The water-based epoxy resin is not particularly limited, and a known water-based epoxy resin can be used. Examples of the aqueous epoxy resin include diglycidyl ether of bisphenol A and oligomers thereof, diglycidyl ether of hydrogenated bisphenol A and oligomers thereof, orthophthalic acid diglycidyl ester, isophthalic acid diglycidyl ester, terephthalic acid diglycidyl ester, p- Oxybenzoic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, succinic acid diglycidyl ester, adipic acid diglycidyl ester, sebacic acid diglycidyl ester, ethylene glycol diglycidyl ether, propylene glycol di Glycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, polyalkyl Glycol diglycidyl ethers, trimellitic acid triglycidyl ester, triglycidyl isocyanurate, 1,4-diglycidyloxybenzene, diglycidyl propylene urea, glycerol triglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol triglycidyl ether And triglycidyl ether of glycerol alkylene oxide adduct. These water-based epoxy resins may be used alone or in combination of two or more. Among these water-based epoxy resins, ethylene glycol diglycidyl ether and propylene glycol diglycidyl ether are preferable.

Commercially available products of the above water-based epoxy resins include, for example, W2801, W2811R70, W2821R70, W3432R67, DX255 (above, jER series, manufactured by Mitsubishi Chemical), 3520WY55, 3540WY55, 5003W55, 5522WY55, 6006W70 (above, Epiletts series, Mitsubishi Chemical) Adeka Resin EM Series (manufactured by ADEKA), EX-611, EX-612, EX-614, EX-614B, EX-512, EX-521, EX-421, EX-313, EX-314, EX -321, EX-810, EX-811, EX-850, EX-851, EX-821, EX-830, EX-832, EX-841, EX-861, EX-911, EX-941, EX-920 , EX-145, EX-17 (Above, manufactured by Nagase Chemtex Corporation), and the like.

In the present specification, the photoacid generator refers to a compound that generates an acid upon irradiation with active energy rays.
Examples of the photoacid generator include (4-methoxyphenyl) dimethylsulfonium triflate represented by the following formula.

Although the compounding quantity of the said photo-acid generator is not specifically limited, The preferable minimum with respect to 100 weight part of said aqueous epoxy resins is 0.5 weight part, and a preferable upper limit is 15 weight part. When the blending amount of the photoacid generator is less than 0.5 parts by weight, the curing efficiency of the photosensitive aqueous epoxy resin composition may be lowered. When the blending amount of the photoacid generator exceeds 15 parts by weight, light absorption of the photoacid generator is strong, so that light does not reach the deep part of the photosensitive aqueous epoxy resin composition and may cause poor curing. . The compounding amount of the photoacid generator is preferably 1.0 part by weight and more preferably 10 parts by weight with respect to 100 parts by weight of the aqueous epoxy resin.

The blending amount of the epoxy resin curing fine particles of the present invention is not particularly limited, but a preferable lower limit with respect to 100 parts by weight of the aqueous epoxy resin is 0.5 parts by weight, and a preferable upper limit is 50 parts by weight. When the compounding amount of the epoxy resin curing fine particles of the present invention is less than 0.5 parts by weight, the curing efficiency of the photosensitive aqueous epoxy resin composition may be lowered. When the blending amount of the epoxy resin curing fine particles of the present invention exceeds 50 parts by weight, the volume shrinkage of the cured product based on the decomposition of the epoxy resin curing fine particles may increase. As for the compounding quantity of the epoxy resin curing fine particles of the present invention, a more preferable lower limit with respect to 100 parts by weight of the aqueous epoxy resin is 1.0 part by weight, and a more preferable upper limit is 20 parts by weight.

In the photosensitive aqueous epoxy resin composition of the present invention, the preferable lower limit of the curing time immediately after irradiation with active energy rays is 0.5 minutes, and the preferable upper limit is 2.0 hours. If the curing time is less than 0.5 minutes, the epoxy resin curing fine particles may not be sufficiently decomposed. When the curing time exceeds 2.0 hours, it takes time to obtain a highly reliable cured product, which may be inferior in productivity. In the photosensitive water-based epoxy resin composition of the present invention, the more preferable lower limit of the curing time immediately after irradiation with active energy rays is 1.0 minute, and the more preferable upper limit is 30 minutes.

ADVANTAGE OF THE INVENTION According to this invention, when mix | blended with the photosensitive water-system epoxy resin composition, the fine particle for epoxy resin hardening which can be excellent in a dispersibility and can improve hardening efficiency can be provided. Moreover, according to this invention, the manufacturing method of this fine particle for epoxy resin hardening, and the photosensitive aqueous epoxy resin composition containing this fine particle for epoxy resin hardening can be provided.

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

Example 1
In a 300 mL round bottom separable flask, 1.5 g of polyvinylpyrrolidone, 150 g of methanol, and 4- (acryloyl) cyclohexyl 4-methylbenzenesulfonate (formula (1) as a monomer having a structure represented by the general formula (1) The monomer having a structure represented by 2-3)) (3.0 g) was added, and the inside of the flask was placed in a nitrogen atmosphere while stirring. Thereafter, a polymerization initiator solution obtained by dissolving 0.15 g of azobisisobutyronitrile in 10 g of methanol as a lipophilic polymerization initiator was added, and polymerization was carried out at 50 ° C. to obtain fine particles. The obtained fine particles were washed with methanol and then dried under reduced pressure to obtain fine particles for epoxy resin curing (volume average particle size 0.93 μm).

(Example 2)
In a 300 mL round bottom separable flask, 2.5 g of polyvinylpyrrolidone, 50 g of methanol, and 4- (acryloyl) cyclohexyl 4-fluorobenzenesulfonate (formula (as a monomer having a structure represented by the general formula (1)) The monomer having a structure represented by 2-7) 0.5 g and Irgacure 819 1 mol% were added, and the inside of the flask was brought into a nitrogen atmosphere while stirring. Thereafter, using a Hg—Xe lamp, light having a wavelength of 365 nm was irradiated at 20 J / cm ² to perform photopolymerization to obtain fine particles. The obtained fine particles were washed with methanol and then dried under reduced pressure to obtain fine particles for epoxy resin curing (volume average particle size of 0.10 to 0.15 μm).

(Example 3)
In a 300 mL round bottom separable flask, 5 g of polyvinylpyrrolidone, 50 g of methanol, and 4- (acryloyl) cyclohexyl 2,4-fluorobenzenesulfonate (formula (5) as a monomer having a structure represented by the general formula (1) The monomer having a structure represented by 2-8) 0.5 g and Irgacure 819 0.5 mol% were added, and the inside of the flask was brought into a nitrogen atmosphere while stirring. Thereafter, using a Hg—Xe lamp, light having a wavelength of 365 nm was irradiated at 20 J / cm ² to perform photopolymerization to obtain fine particles. The obtained fine particles were washed with methanol and then dried under reduced pressure to obtain fine particles for epoxy resin curing (volume average particle size of 0.09 to 0.11 μm).

(Evaluation)
The following evaluation was performed about the fine particle for epoxy resin hardening obtained in the Example. The results are shown in Table 1.

(1) Dispersibility with respect to aqueous epoxy resin 1 part by weight of a 10% by weight dispersion of epoxy resin curing particles obtained in Examples 1 to 3 and a water-soluble photoacid generator (4-methoxyphenyl) dimethylsulfonium triflate 0 0.5 parts by weight, 10 parts by weight of an aqueous epoxy resin (EX-512, manufactured by Nagase ChemteX Corporation) and 20 parts by weight of water were stirred and mixed using a homodisper to prepare an aqueous epoxy resin composition. Further, 0.5 part by weight of a water-soluble photoacid generator (4-methoxyphenyl) dimethylsulfonium triflate, 10 parts by weight of an aqueous epoxy resin (EX-512, manufactured by Nagase ChemteX Corporation), and 20 parts by weight of water, The mixture was stirred and mixed using a homodisper to prepare an aqueous epoxy resin composition as a comparative example (Comparative Example 1).

The obtained water-based epoxy resin composition was applied to a thickness of 500 μm, and the coating film was irradiated with light having a wavelength of 254 nm at 100 mJ / cm ² and then heated at 140 ° C. for 10 minutes. After removing the uncured portion of the aqueous epoxy resin composition after heating with ethyl methyl ketone, the aqueous epoxy resin composition was vacuum dried. By observing the cross section of the water-based epoxy resin composition after drying with a scanning electron microscope, the dispersibility of the epoxy resin curing fine particles in the water-based epoxy resin was evaluated. The case where the cavity of the uncured part was not seen was marked with ◯, and the case where the cavity of the uncured part was confirmed was marked with x. If the epoxy resin curing fine particles are not uniformly dispersed, an uncured portion remains, and the uncured portion is eluted with ethyl methyl ketone, resulting in a void in the uncured portion.

(2) Reliability of cured product 0.05 g of a 10% by weight dispersion of epoxy resin curing particles obtained in Examples 1 to 3 and a water-soluble photoacid generator (4-methoxyphenyl) dimethylsulfonium triflate 0025 g and 0.05 g of an aqueous epoxy resin (EX-512, manufactured by Nagase ChemteX Corporation) were mixed with stirring to prepare a photosensitive aqueous epoxy resin composition. Further, 0.0025 g of a water-soluble photoacid generator (4-methoxyphenyl) dimethylsulfonium triflate, 0.05 g of an aqueous epoxy resin (EX-512, manufactured by Nagase ChemteX Corporation), and 0.1 g of water are mixed with stirring. A photosensitive aqueous epoxy resin composition was prepared as a comparative example (Comparative Example 1).

The obtained photosensitive aqueous epoxy resin composition is bar-coated on a glass substrate to prepare a coating film. The coating film is irradiated with light having a wavelength of 254 nm at 100 mJ / cm ² and then at 140 ° C. for 10 minutes. Heating was performed. The hardness of the obtained cured film was evaluated by a pencil hardness test. In the pencil hardness test, the cured film was scratched with a pencil, and a state in which scratches of 3 mm or more were included was regarded as a defect, and the hardest pencil hardness without scratches was evaluated. The higher the pencil hardness, the higher the reliability of the cured product. In addition, about the photosensitive aqueous epoxy resin composition of the comparative example 1, hardening was not seen but it did not reach the film | membrane to evaluate.

(3) Storage stability The epoxy resin curing fine particles obtained in Examples 1 to 3 and the bisphenol A type epoxy resin (JER828, manufactured by Mitsubishi Chemical Corporation) were mixed at a weight ratio of 1:10 to obtain an epoxy resin composition. 300 g was prepared. A water-soluble photoacid generator (4-methoxyphenyl) dimethylsulfonium triflate and a bisphenol A type epoxy resin (JER828, manufactured by Mitsubishi Chemical Corporation) are mixed at a weight ratio of 1:20 to prepare 300 g of an epoxy resin composition. And it was set as the comparative example (comparative example 1).
The viscosity (Pa · s) at 25 ° C. of the obtained epoxy resin composition was measured with a B-type viscometer. Thereafter, the viscosity (Pa · s) after the epoxy resin composition was allowed to stand at 25 ° C. for 30 days in a light-shielded thermostatic chamber was measured. The storage stability was evaluated by calculating the difference in viscosity between before and after storage (25 ° C., before and after standing for 30 days).

ADVANTAGE OF THE INVENTION According to this invention, when mix | blended with the photosensitive water-system epoxy resin composition, the fine particle for epoxy resin hardening which can be excellent in a dispersibility and can improve hardening efficiency can be provided. Moreover, according to this invention, the manufacturing method of this fine particle for epoxy resin hardening, and the photosensitive aqueous epoxy resin composition containing this fine particle for epoxy resin hardening can be provided.

Claims (5)

A photosensitive aqueous epoxy resin curing fine particle comprising fine particles having a group that causes an acid proliferation reaction on the surface,
It is obtained by polymerizing a radically polymerizable monomer containing a monomer having a structure represented by the following general formula (1) in water, alcohol or a mixture of water and alcohol ,
The radical polymerizable monomer is a content of a radical polymerizable monomer other than the monomer having the structure represented by the following general formula (1) with respect to 100 parts by weight of the monomer having the structure represented by the following general formula (1). There Ri der less than 50 parts by weight,
The photosensitive water-based epoxy resin curing fine particles , wherein the group that causes an acid proliferation reaction has a structure that causes an acid proliferation reaction represented by the following general formula (2) or (3) .

In general formula (1), X represents a hydrogen atom or a methyl group, and A represents a group that causes an acid proliferation reaction.

In general formulas (2) and (3), R ¹ represents an aromatic group or an aliphatic group, and n represents an integer. The fine particles for curing a photosensitive aqueous epoxy resin according to claim 1, wherein the volume average particle diameter is 0.03 μm or more and 0.5 μm or less. The fine particle for curing a photosensitive aqueous epoxy resin according to claim 1 or 2 , wherein an emulsifier, a water-soluble polymer or a dispersant is adsorbed on the surface. A method for producing fine particles for curing a photosensitive aqueous epoxy resin having a group that causes an acid proliferation reaction on the surface,
In a mixture of water, alcohol or water and alcohol, a radical polymerizable monomer containing a monomer having a structure represented by the following general formula (1) is polymerized:
The radical polymerizable monomer is a content of a radical polymerizable monomer other than the monomer having the structure represented by the following general formula (1) with respect to 100 parts by weight of the monomer having the structure represented by the following general formula (1). There Ri der less than 50 parts by weight,
The method for producing fine particles for curing photosensitive water-based epoxy resin , wherein the group that causes an acid proliferation reaction has a structure that causes an acid proliferation reaction represented by the following general formula (2) or (3) : .

In general formula (1), X represents a hydrogen atom or a methyl group, and A represents a group that causes an acid proliferation reaction.

In general formulas (2) and (3), R ¹ represents an aromatic group or an aliphatic group, and n represents an integer. A photosensitive aqueous epoxy resin, a photoacid generator, according to claim 1, 2 or 3 photosensitive aqueous epoxy resin composition characterized by containing a photosensitive aqueous epoxy resin curing microparticles according.