JP2001040068A - Photopolymerizable composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a photopolymerizable composition curable at a low temperature in a short time, having excellent moisture resistance at a high temperature and a high humidity, excellent adhesion characteristics to various materials, capable of curing a part such as an overhang part not to be directly exposed to the sun. SOLUTION: This photocurable composition comprises a cationic polymerizable substance (1) composed of >=1 wt.% and <=75 wt.% of an epoxy- modified butadiene resin (a) and >=25 wt.% and <=99 wt.% of a cationic polymerizable organic substance (b) except the epoxy-modified butadiene resin (a) and an energy ray sensitive polymerization initiator (2) as essential components.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photopolymerizable composition, and more particularly to a photopolymerizable composition in which a cured film after a photopolymerization reaction has both moisture resistance and excellent adhesion to various substrates.

[0002]

2. Description of the Related Art Conventionally, mounting devices, such as epoxy resin, acrylic resin, silicone resin, phenol resin or polyimide resin, which are hardened by heat, are used to protect mounting devices which are extremely sensitive to humidity such as electronic and electric parts. Adhesives and the like are widely used.

[0003] Such protective coatings, fillers,
Adhesives are widely used to protect mounted circuit boards, ICs, diodes, transistors, capacitors, coils, etc., in which high-temperature, high-humidity conditions are maintained for a long period of time. Used for various applications.

However, conventional protective coating agents, fillers, and adhesives are thermosetting resins, which require a long curing treatment to achieve a predetermined performance, and are difficult to mount on heat-sensitive mounting boards. Had the disadvantage that it was difficult to adapt.

[0005] Furthermore, in order to ensure storage stability, it is possible to supply them in two liquids and mix them immediately before use. In order to solve this problem, the one-part curable resin and curing agent are used to simplify the handling. There was a problem that it was difficult to achieve both.

On the other hand, JP-A-61-118414 and JP-A-61-120864 disclose compositions of an epoxy acrylate resin, a silane coupling agent and a peroxide. These can be cured at a lower temperature and in a shorter time than conventional thermosetting resins, but must be stored at a low temperature to suppress decomposition of peroxides. The problems associated with the resin could not be fundamentally solved.

[0007] Ultraviolet curing has also been proposed as a system for curing in a short time at a low temperature.
There is also a problem that a moisture-proof property, an adhesive property, etc. are insufficient, and a complicated adhesive part, that is, a part which is hardly irradiated with ultraviolet light, such as an overhang part, is not cured.

Further, JP-A-7-238240 discloses a composition containing a photopolymerizable terminal (meth) acryloxypolybutadiene, a wax, and a radical photopolymerization initiator. It could not be solved.

[0009]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a curing treatment which can be performed at a low temperature and in a short time, has a good moisture-proof property at a high temperature and a high humidity, and has a good adhesive property to various materials. Another object of the present invention is to provide a photopolymerizable composition capable of curing a portion which is not directly irradiated with ultraviolet rays such as an overhang portion.

[0010]

In order to solve the above-mentioned problems, the photopolymerizable composition of the present invention comprises, as an essential component, 1% by weight or more and 75% by weight of an epoxy-modified butadiene resin (a).
The following, 25% by weight or more and 99% by weight of a cationically polymerizable organic substance (b) other than the epoxy-modified butadiene resin (a)
It is characterized by containing a cationic polymerizable substance (1) comprising the following and an energy ray-sensitive cationic polymerization initiator (2).

In the photopolymerizable composition of the present invention, the epoxy-modified butadiene resin (a) has a number average molecular weight of 100
It is preferably in the range of 10,000 to 10,000, and the epoxy-modified butadiene resin (a) may be a hydrogenated one. Further, the cationically polymerizable organic substance (b) other than the epoxy-modified butadiene resin (a) includes bisphenol A-type epoxy resin and its modified product, hydrogenated bisphenol A-type epoxy resin and its modified product, bisphenol F-type epoxy resin and its It is preferably at least one selected from the group consisting of a modified product, a hydrogenated bisphenol F type epoxy resin and a modified product thereof, a novolak phenol resin and a modified product thereof, an alicyclic epoxy resin and a modified product thereof.

[0012]

Embodiments of the present invention will be described below. Cationic polymerizable substance (1) in the present invention
Comprises an epoxy-modified butadiene resin (a) and a cationically polymerizable organic substance (b) other than the epoxy-modified butadiene resin (a).

The epoxy-modified butadiene resin (a) used in the present invention is not particularly limited, and epoxy obtained by epoxidizing polybutadiene by a conventional method and / or introducing an epoxy group into polybutadiene by a conventional method. All modified butadiene resins can be used.

The polybutadiene used herein is 1,
Either 2-butadiene or 1,4-polybutadiene may be used, and any mixture thereof may be used. Preferably, a polybutadiene having a number average molecular weight of 100 to 10,000, more preferably 500 to 5,000 is used.

[0015] The method of epoxy modification is not limited at all. Examples of a very small number of methods include, for example, a method of reacting an oxidizing agent such as peracetic acid with a double bond of polybutadiene to effect epoxidation. A method in which a hydroxyl group is introduced into the terminal of 1,2-polybutadiene, the hydroxyl group is further urethanized with isocyanate, and a primary hydroxyl group-containing epoxy compound is reacted therewith to introduce an epoxy group.

In the epoxy-modified butadiene resin used in the present invention, the degree of epoxy modification is not particularly limited, but is preferably 50 to 1000 meq / epoxy equivalent.
g, more preferably 70 to 500 meq / g.

As the epoxy-modified butadiene resin that can be used in the present invention, those sold as general commercial products can also be used. For example, BF-1000 (trade name, manufactured by Asahi Denka Kogyo Co., Ltd., Japan) EPB-13 and EPB-1054 (trade names) manufactured by Soda Co., Ltd., and E-700-3.5 and E-7 (trade names) manufactured by Nippon Petrochemical Co., Ltd.
00-6.5, E-1000-3.5, E-100
0-6.5, E-1000-8, E-1800-
6.5 and the like. These can be used alone or in combination of two or more.

The epoxy-modified butadiene resin (a) used in the present invention may be a hydrogenated one. Hydrogen may be added at any stage, after polybutadiene is epoxy-modified, hydrogen may be added to the remaining double bond, or after partially hydrogenating polybutadiene, the remaining double bond is epoxidized. Is also good. When an epoxy group is introduced after terminal modification, hydrogenation may be performed before or after epoxy modification.

The cationically polymerizable organic substance (b) other than the epoxy-modified butadiene resin (a) used in the present invention is a substance which undergoes a polymerization or a cross-linking reaction by an energy ray-sensitive cationic polymerization initiator. Specifically, for example, an epoxy compound, a cyclic ether compound, an oxetane compound, a cyclic lactone compound, a cyclic acetal compound, a cyclic thioether compound, a spiroorthoester compound, a vinyl compound, etc., and one or more of these are used be able to. Among them, epoxy compounds that are easily available and convenient to handle are suitable. As such an epoxy compound, an aromatic epoxy resin, an alicyclic epoxy resin, an aliphatic epoxy resin and the like are suitable.

Specific examples of the aromatic epoxy resin include a polyhydric phenol having at least one aromatic ring or a polyglycidyl ether of an alkylene oxide adduct thereof, for example, bisphenol A, bisphenol F,
Glycidyl ether of a compound obtained by further adding an alkylene oxide thereto, an epoxy novolak resin,
Examples include bisphenol A novolak diglycidyl ether and bisphenol F novolak diglycidyl ether.

Specific examples of the alicyclic epoxy resin are obtained by epoxidizing a polyglycidyl ether of a polyhydric alcohol having at least one alicyclic ring or a compound containing a cyclohexene or cyclopentene ring with an oxidizing agent. And a compound having a vinylcyclohexane oxide structure obtained by epoxidizing a compound having a cyclohexene oxide structure, a compound having a cyclopentene oxide structure, or a compound having a vinylcyclohexane structure with an oxidizing agent.
For example, hydrogenated bisphenol A diglycidyl ether, 3,4-epoxycyclohexylmethyl-3,4-
Epoxycyclohexyl carboxylate, 3,4-epoxy-1-methylcyclohexyl-3,4-epoxy-1-methylcyclohexanecarboxylate, 6-methyl-3,4-epoxycyclohexylmethyl-6-methyl-3,4-epoxy Cyclohexanecarboxylate, 3,4-epoxy-3-methylcyclohexylmethyl-3,4-epoxy-3-methylcyclohexanecarboxylate, 3,4-epoxy-5-methylcyclohexylmethyl-3,4-epoxy-5-methyl Cyclohexanecarboxylate, 2- (3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy) cyclohexane-metadioxane, bis (3,4-epoxycyclohexylmethyl) adipate, vinylcyclohexene dioxide 4-vinyl epoxycyclohexane, bis (3,4-epoxy-6-methylcyclohexyl methyl) adipate, 3,4-epoxy-6-methylcyclohexyl carboxylate, methylene bis (3,
4-epoxycyclohexane), dicyclopentadiene diepoxide, ethylene glycol di (3,4-epoxycyclohexylmethyl) ether, ethylene bis (3,4-epoxycyclohexanecarboxylate), dioctyl epoxyhexahydrophthalate, epoxyhexahydrophthalate And di-2-ethylhexyl acid.

Specific examples of the aliphatic epoxy resin include a polyglycidyl ether of an aliphatic polyhydric alcohol or an alkylene oxide adduct thereof, a polyglycidyl ester of an aliphatic long-chain polybasic acid, and an aliphatic long-chain unsaturated hydrocarbon. And glycidyl acrylate or glycidyl methacrylate homopolymer, glycidyl acrylate or glycidyl methacrylate copolymer, and the like. Representative compounds include 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, triglycidyl ether of glycerin, triglycidyl ether of trimethylolpropane, tetraglycidyl ether of sorbitol, dipentaerthry Glycidyl ethers of polyhydric alcohols such as hexaglycidyl ether of tall, diglycidyl ether of polyethylene glycol, and diglycidyl ether of polypropylene glycol; and one or more alkylenes in aliphatic polyhydric alcohols such as propylene glycol and glycerin. The polyglycidyl ether of a polyether polyol obtained by adding an oxide and the diglycidyl ester of an aliphatic long-chain dibasic acid can be used. Furthermore, monoglycidyl ethers of aliphatic higher alcohols, phenol, cresol, butylphenol, monoglycidyl ethers of polyether alcohols obtained by adding alkylene oxides to these, glycidyl esters of higher fatty acids, epoxidized soybean oil, epoxy stearin Octyl acid, butyl epoxystearate, epoxidized linseed oil and the like can be mentioned.

The cationically polymerizable organic substance (b) other than the epoxy-modified butadiene resin (a) includes, but is not limited to, bisphenol A type epoxy resin and its modified product, hydrogenated bisphenol A resin and its Modified products, bisphenol F type epoxy resins and modified products thereof, hydrogenated bisphenol F type epoxy resins and modified products thereof, novolak phenol resins and modified products thereof, and alicyclic epoxy resins and modified products thereof are preferred. Here, the “modified product” is a modified product within the range of conventional modification in the technical field to which the invention belongs.

The epoxy-modified butadiene resin (a) in the cationically polymerizable substance (1) is preferably from 1% by weight to 75% by weight, more preferably from 3% by weight to 50% by weight.
Used in an amount of 25% by weight or less (in other words, preferably 25% by weight or more and 99% by weight or less, more preferably 25% by weight or more and 99% by weight or less of the cationically polymerizable organic substance (b) other than the epoxy-modified butadiene resin (a)). Used in).

If the amount of the epoxy-modified butadiene resin (a) in the cationically polymerizable substance (1) is less than the above-mentioned amount, the adhesiveness to the adhesive substrate is poor, and the moisture-proof property is also insufficient.

If the amount is more than the above range, the resulting adhesive layer becomes excessively flexible, so that a strong adhesive force cannot be obtained at high temperatures.

The energy ray-sensitive cationic polymerization initiator (2) in the present invention is a compound capable of releasing a substance which initiates the polymerization of the polymerizable organic substance upon irradiation with energy rays. A double salt that is an onium salt that releases a Lewis acid upon irradiation, or a derivative thereof. Representative examples of such compounds include salts of cations and anions represented by the general formula [A] ^{m +} [B] ^m- .

[0028] Here, it is preferable ⁺ cation ^{A m} is an onium, and its structure, for example, can be represented by _{^{[(R 1) a Z]}} m +.

Further, R ¹ is an organic group having ¹ to 60 carbon atoms and which may contain any number of atoms other than carbon. a is an integer of 1 to 5. a number of R ¹ are each independently, it may be the same or different. Also, at least one
One is preferably an organic group having an aromatic ring as described above. Z is S, N, Se, Te, P, As, Sb,
An atom or atomic group selected from the group consisting of Bi, O, I, Br, Cl, F, and N = N. Also, cation A
^{When the} valence of Z in ^{m +} is z, it is necessary that the relationship m = az is satisfied.

Further, the anion ^{B m-is} preferably a halide complex, and its structure, for example, can be represented by _[LX ^{b] m-.}

Here, L is a metal or metalloid which is a central atom of the halide complex, and B, P, As, Sb, Fe, Sn, Bi, Al,
Ca, In, Ti, Zn, Sc, V, Cr, Mn, Co
And so on. X is a halogen. b is an integer of 3 to 7. Further, when the valence of L in the anion B ^m− is p, it is necessary that the relationship m = bp holds.

Specific examples of the anion [LX _b ] ^{m- in} the above general formula include tetrafluoroborate (BF ₄ ) ⁻ , hexafluorophosphate (PF ₆ ) ⁻ , hexafluoroantimonate (SbF ₆ ) ⁻ , hexafluoro Arsenate (AsF ₆ ) ⁻ , hexachloroantimonate (SbCl ₆ ) ^{− and the} like.

Further, the anion ^{B m-may} be preferably used a structure represented by ^{_{m- [LX b-1 (OH}} )].
L, X and b are the same as above. Other anions that can be used include perchlorate ion (ClO
₄ ) ⁻ , trifluoromethyl sulfite ion (CF ₃ SO
₃ ) ⁻ , fluorosulfonic acid ion (FSO ₃ ) ⁻ , toluenesulfonic acid anion, trinitrobenzenesulfonic acid anion, and the like.

Further, as ^m- anion ^B, it is possible to also use preferably tetrakis (pentafluorophenyl) borate.

In the present invention, among such onium salts, it is particularly effective to use an aromatic onium salt. Among them, JP-A-50-151997 and JP-A-50-501997
Aromatic halonium salts described in JP-A-158680, JP-A-50-151997, JP-A-52-30899
JP-A-56-55420, JP-A-55-1251
No. 05, etc., a group VIA aromatic onium salt described in JP-A-50-158698, JP-A-56-8428, JP-A-56-1494.
No. 02, oxosulfoxonium salts described in JP-A-57-192429, aromatic diazonium salts described in JP-A-49-17040, U.S. Pat. No. 4,139,655.
And the like are preferred. Also,
Other preferable examples include an iron / allene complex and an aluminum complex / photolytic silicon compound-based initiator.

Among these aromatic onium salts, particularly preferred are those as cations. Or (Wherein, R represents a hydrogen atom, a halogen atom, or a hydrocarbon group optionally containing an oxygen atom or a halogen atom, or an alkoxy group optionally having a substituent, and Ar represents one or more hydrogen atoms. Which is a phenyl group whose atom may be substituted) and (tolylcumyl) iodonium, bis (tert-butylphenyl) iodonium, triphenylsulfonium and the like. For example, 4,4'-
Bis (di (β-hydroxyethoxy) phenylsulfonio) phenylsulfide-bis-hexafluorophosphate, 4- (4-benzoyl-phenylthio) phenyl-di- (4-fluorophenyl) sulfonium hexafluorophosphate, 4,4 '-Bis (di (β-hydroxyethoxy) phenylsulfonio) phenylsulfide-bis-hexafluorophosphate, 4,
4′-bis (di (β-hydroxyethoxy) phenylsulfonio) phenylsulfide-bis-hexafluoroantimonate, 4,4′-bis (difluorophenylsulfonio) phenylsulfide-bis-hexafluorophosphate, 4,4 '-Bis (difluorophenylsulfonio) phenylsulfide-bis-hexafluoroantimonate, 4,4'-bis (phenylsulfonio) phenylsulfide-bis-hexafluorophosphate, 4,4'-bis (phenylsulfonio) Phenyl sulfide-bis-hexafluoroantimonate,
4- (4-benzoylphenylthio) phenyl-di-
(4- (β-hydroxyethoxy) phenyl) sulfonium hexafluorophosphate, 4- (4-benzoylphenylthio) phenyl-di- (4- (β-hydroxyethoxy) phenyl) sulfonium hexafluoroantimonate, 4- (4 -Benzoylphenylthio) phenyl-di- (4-fluorophenyl) sulfonium hexafluorophosphate, 4- (4-benzoylphenylthio) phenyl-di- (4-fluorophenyl) sulfonium hexafluoroantimonate, 4- (4-
Benzoylphenylthio) phenyl-diphenylsulfonium hexafluorophosphate, 4- (4-benzoylphenylthio) phenyl-diphenylsulfonium hexafluoroantimonate, 4- (phenylthio)
Phenyl-di- (4- (β-hydroxyethoxy) phenyl) sulfonium hexafluorophosphate,
(Phenylthio) phenyl-di- (4- (β-hydroxyethoxy) phenyl) sulfonium hexafluoroantimonate, 4- (phenylthio) phenyl-di-
(4-fluorophenyl) sulfonium hexafluorophosphate, 4- (phenylthio) phenyl-di-
(4-fluorophenyl) sulfonium hexafluoroantimonate 4- (phenylthio) phenyl-diphenylsulfonium hexafluorophosphate,
(Phenylthio) phenyl-diphenylsulfonium hexafluoroantimonate, 4- (2-chloro-4-
Benzoylphenylthio) phenylbis (4-fluorophenyl) sulfonium hexafluorophosphate,
4- (2-chloro-4-benzoylphenylthio) phenylbis (4-fluorophenyl) sulfonium hexafluoroantimonate, 4- (2-chloro-4-benzoylphenylthio) phenyldiphenylsulfonium hexafluorophosphate, 4- ( 2-chloro-4-
Benzoylphenylthio) phenyldiphenylsulfonium hexafluoroantimonate, 4- (2-chloro-4-benzoylphenylthio) phenylbis (4-hydroxyphenyl) sulfonium hexafluorophosphate, 4- (2-chloro-4-benzoylphenylthio ) Phenylbis (4-hydroxyphenyl) sulfonium hexafluoroantimonate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, (tolylcumyl) iodonium hexafluorophosphate, (tolylcumyl) iodonium hexafluoroantimonate, (tolylcumyl) Iodonium tetrakis (pentafluorophenyl) borate, bis (tert-butylphenyl) iodine Umm hexafluorophosphate,
Bis (tertiarybutylphenyl) iodonium hexafluoroantimonate, bis (tertiarybutylphenyl) iodoniumtetrakis (pentafluorophenyl) borate, benzyl-4-hydroxyphenylmethylsulfonium hexafluorophosphate, benzyl-4-hydroxyphenylmethylsulfonium hexa Fluoroantimonate, benzyldimethylsulfonium hexafluorophosphate, benzyldimethylsulfonium hexafluoroantimonate, p-chlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluorophosphate, p-chlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 4-acetoxyphenyldimethylsulfonium hexaflu Lophosphate, 4-acetoxyphenyldimethylsulfonium hexafluoroantimonate, 4-methoxycarbonyloxyphenyldimethylsulfonium hexafluorophosphate, 4-methoxycarbonyloxyphenyldimethylsulfonium hexafluoroantimonate, 4-ethoxycarbonyloxyphenyldimethylsulfonium hexafluorophosphate , 4-ethoxycarbonyloxyphenyldimethylsulfonium hexafluoroantimonate, α-
Naphthylmethyldimethylsulfonium hexafluorophosphate, α-naphthylmethyldimethylsulfonium hexafluoroantimonate, α-naphthylmethyltetramethylenesulfonium hexafluorophosphate, α-naphthylmethyltetramethylenesulfonium hexafluoroantimonate, cinnamyldimethylsulfonium hexafluorophosphate, Cinnamyldimethylsulfonium hexafluoroantimonate, cinnamyltetramethylenesulfonium hexafluorophosphate, cinnamyltetramethylenesulfonium hexafluoroantimonate, N- (α-phenylbenzyl) -2-cyanopyridinium hexafluorophosphate, N- (α- Phenylbenzyl) -2-cyanopyridinium hexafluoro Antimonate, N-cinnamyl-2-cyanopyridinium hexafluorophosphate, N-cinnamyl-2-cyanopyridinium hexafluoroantimonate, N- (α-naphthylmethyl)-
2-cyanopyridinium hexafluorophosphate,
N- (α-naphthylmethyl) -2-cyanopyridinium hexafluoroantimonate, N-benzyl-2-cyanopyridinium hexafluorophosphate, N-benzyl-2-cyanopyridinium hexafluoroantimonate and the like can be mentioned.

The preferable amount of the energy ray-sensitive cationic polymerization initiator (2) used is 0.1 to 100 parts by weight of the total amount of the cationically polymerizable organic substance (1).
It is good to prepare with 1 to 50 parts by weight, more preferably 0.5 to 10 parts by weight.

If the amount of the energy-ray-sensitive cationic polymerization initiator is too large, the cured film becomes brittle, and if the amount is too small, the curing speed becomes extremely slow.

Although not essential for the photopolymerizable composition of the present invention, if necessary, an organic compound having two or more hydroxyl groups in one molecule may be replaced with a cationically polymerizable organic substance (1).
1 to 20 parts by weight can be added to 100 parts by weight. For example, polyhydric alcohol, hydroxyl group-containing polyether, hydroxyl group-containing polyester, polyhydric phenol, etc.
The curing rate can be improved by blending an organic compound having two or more hydroxyl groups in the molecule,
If it exceeds 20 parts by weight, the moisture permeability deteriorates.

Examples of polyhydric alcohols include ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, glycerin, pentaerythritol, dipentaerythritol, 1,3-butanediol, 1,4-butanediol, 6-hexanediol and the like.

The hydroxyl group-containing polyether is a compound obtained by adding one or more alkylene oxides to one or more polyhydric alcohols or phenols. Examples of the polyhydric alcohol used for this include ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, glycerin, pentaerythritol, dipentaerythritol, 1,3-butanediol, 1,4-butanediol. , 1,6-hexanediol and the like. Examples of the polyhydric phenol include bisphenol A, bisphenol F, phenol novolak resin, and cresol novolak resin. Examples of the alkylene oxide include butylene oxide, propylene oxide, and ethylene oxide.

The hydroxyl group-containing polyester is a hydroxyl group-containing polyester obtained by an esterification reaction of one or more polyhydric alcohols or polyphenols with one or more monobasic acids or polybasic acids. And a hydroxyl group-containing polyester obtained by an esterification reaction of one or more polyhydric alcohols or phenols with one or more lactones. Examples of the polyhydric alcohol and the polyhydric phenol include the same as those described above. Examples of the monobasic acid include formic acid, acetic acid, butyric acid, and benzoic acid. Examples of the polybasic acid include adipic acid, terephthalic acid, trimellitic acid and the like. Lactones include β-propiolactone, γ-butyrolactone, ε-caprolactone, and the like.

A polyhydric phenol is a compound containing two or more hydroxyl groups directly bonded to an aromatic ring in one molecule.
The same as those described above can be used.

Although not essential for the photopolymerizable composition of the present invention, an inorganic powder insoluble in the photopolymerizable composition of the present invention can be used as a filler if necessary.
For example, calcium carbonate, barium carbonate, barium sulfate, fused silica, titanium white, etc. When blending such an insoluble inorganic powder in the photopolymerizable composition of the present invention, excessive blending causes an extreme decrease in transparency,
Curability may be deteriorated. Although it cannot be said unconditionally depending on the particle size and type of the insoluble inorganic powder to be compounded, in general,
The blending amount is preferably from 1 part by weight to 50 parts by weight based on 100 parts by weight of the cationically polymerizable substance (1) of the present invention.

Although not essential, a radical polymerizable substance such as a (meth) acrylic resin and an energy ray-sensitive material are used in an amount of less than 20 parts by weight based on 100 parts by weight of the cationic polymerizable substance (1) of the present invention. A radical polymerization initiator can be blended.

The photopolymerizable composition of the present invention is polymerized and cured by irradiation with active energy rays. Examples of the active energy rays include ultraviolet rays, electron beams, X-rays, radiation, and high frequencies, and ultraviolet rays are the most economical and preferable. Examples of the ultraviolet light source include an ultraviolet laser, a mercury lamp, particularly a (ultra) high-pressure mercury lamp, a xenon lamp, an alkali metal lamp, and a commercially available electrodeless lamp (for example, V bulb (trade name) manufactured by Fusion, D
Valve (trade name)). When position selectivity is required for polymerization and curing of the photopolymerizable composition of the present invention, a laser beam having a good light-collecting property (especially an oscillation wavelength of 300
nm to 450 nm) is preferred. If the position selectivity is not so high, a mercury lamp or the like is economical and preferable.

The photopolymerizable composition of the present invention is such that the cured product after the photopolymerization reaction is excellent in transparency, has good moisture-proof properties at high temperature and high humidity, has good adhesive properties to various materials, and has an overhang. It is very useful as a moisture-proof paint, a moisture-proof adhesive, and a moisture-proof sealant, for example, which can harden even a part that is not directly exposed to ultraviolet rays, such as a part.

In the photopolymerizable composition of the present invention, the optimum cured film thickness may be set according to the intended use. Although not limited to the following description, generally, when used as a moisture-proof paint for a thin film film or the like, 500 μm
Hereinafter, it is preferable to apply the coating so as to have a thickness of preferably 1 to 100 μm.

When used as a moisture-proof adhesive, the distance between the adherends is 1000 μm or less, preferably 1 to 200 μm.
m.

5 mm when used as a moisture-proof sealant
Hereinafter, it is preferable to apply the coating so as to have a thickness of preferably 0.1 to 3 mm or less.

If each of the film thicknesses is less than the described film thickness, sufficient moisture-proof properties cannot be obtained. Further, when the coating is applied in a thickness exceeding the described film thickness, the curability in the deep part direction is deteriorated.

[0052]

Next, the present invention will be described based on embodiments. Photopolymerizable compositions having the composition shown in Tables 1 and 2 below were prepared and evaluated as follows. The results obtained are shown in Tables 1 and 2. The evaluation method in the present invention is described below.

Moisture permeability test: A fluorine-based release agent was applied to a 3 mm-thick blue plate glass, and 300 μm spacers were placed on both sides of the blue plate glass. After compounding, the photopolymerizable composition sufficiently degassed in a vacuum is placed on the above-mentioned soda lime glass, and similarly sandwiched between soda lime glass coated with a fluorine release agent,
It was extended until it became the thickness of. 100 sides with high pressure mercury lamp
Irradiation with an energy beam of 0 mJ / cm ² (100
0 mJ / cm ² ), and a cured test piece was taken out from the blue plate glass and left at room temperature overnight to form a measurement cured film, and a measurement sample was prepared using the measurement cured film.

The method of preparing the measurement sample is JIS Z 2
08. The prepared sample was subjected to a temperature of 40 ° C. and a relative humidity of 90 ± 2%, and a temperature of 85 ° C. and a relative humidity of 85 ± 2%.
And the moisture permeability was measured according to the method of JIS. (Unit: g / m ² , 24 hr)

Adhesion test 1: coating thickness of 100 on various bases
coated with a thickness of μm, sandwiched between the same substrate, and irradiated with an energy ray of 1000 mJ / cm ^{2 by} a high pressure mercury lamp,
The photopolymerizable composition was cured and left at room temperature overnight. Furthermore, after leaving for 3 days in an environment of a temperature of 23 ° C. and a relative humidity of 65%, the peel strength was measured by a T-shaped peel test. (Unit: K
g / 25mm)

Adhesion test 2: Test pieces were prepared according to Adhesion test 1. After leaving for 3 days in an environment at a temperature of 80 ° C. and a relative humidity of 65%, a T-peel test was performed under the same conditions to measure the peel strength. (Unit: Kg / 25mm)

Adhesion test 3: Test pieces were prepared according to Adhesion test 1. The T-peel test was carried out at a temperature of 23 ° C. and a relative humidity of 65% for 100 hours, and the T-peel test was carried out at a temperature of 23 ° C. and a relative humidity of 65%. It was measured. (Unit: Kg / 25
mm)

Overhang curing test: The photocurable composition 3 as a test piece was placed on an aluminum plate 4 using the test device shown in FIG.
Irradiated with energy beam of cm ² and left overnight. After standing overnight, the aluminum light-shielding cover 1 was removed, and the degree of curing of the light-shielding portion was evaluated by finger touch. In addition, the pass was a state in which there was no tackiness by touch. In the case of tack residue and uncured state, the fact is described. The compounds represented by the abbreviations for the resin, filler and polymerization initiator described in Tables 1 and 2 are as follows, and all the numerical values are parts by weight. The surface-treated PET in the table is manufactured by Toray Industries, Inc. under the trade name Lumirror U-9.
8 was used. Epoxy resin 1: 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate Epoxy resin 2: bisphenol A diglycidyl ether Epoxy resin 3: bisphenol F diglycidyl ether Epoxy-modified butadiene resin 1: Epoxy-modified 1,4-
Polybutadiene oligomer (number average molecular weight 1500: trade name E-1000-8 manufactured by Nippon Petrochemical Co., Ltd.) Epoxy-modified butadiene resin 2: epoxy-modified 1,4-
Hydrogenated polybutadiene oligomer (number average molecular weight 1500: trade name E-1000-8 manufactured by Nippon Petrochemical Co., Ltd.) Photocationic polymerization initiator: 4,4′-bis (di (β-hydroxyethoxy) phenylsulfur Fonio) phenyl sulfide-bis-hexafluoroantimonate Acrylic resin: Bisphenol A type epoxy-modified diacrylate Photoradical polymerization initiator: 1-hydroxycyclohexyl phenyl ketone Filler: Calcium carbonate powder (Reagent manufactured by Kanto Chemical Co., Ltd.)

[0059]

[Table 1]

[0060]

[Table 2]

[0061]

As described above, the photopolymerizable composition of the present invention has good moisture-proof properties at high temperature and high humidity and good adhesion to various materials by using an epoxy-modified butadiene resin. It also has excellent properties such that it has properties and is capable of curing a portion that is not directly exposed to ultraviolet rays, such as an overhang portion.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a test apparatus used for an overhang curing test in an example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aluminum light-shielding cover 2 High-pressure mercury lamp 3 Photocurable composition 4 Aluminum plate

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Kazuo Okawa 2-35 Higashiogu, Arakawa-ku, Tokyo Asahi Denka Kogyo Co., Ltd. F-term (reference) 4J036 AA05 AC08 AD08 AF06 AK03 BA02 GA01 GA04 GA06 GA19 GA20 GA22 GA23 GA24 GA25 HA01 HA13 JA06 JA07

Claims (4)

[Claims] An essential component is an epoxy-modified butadiene resin (a) in an amount of 1% by weight to 75% by weight, and a cationically polymerizable organic substance (b) other than the epoxy-modified butadiene resin (a) in an amount of 25% by weight to 99%. A photopolymerizable composition comprising a cationically polymerizable substance (1) consisting of at most 1% by weight and an energy ray-sensitive cationic polymerization initiator (2). 2. The epoxy-modified butadiene resin (a)
The photopolymerizable composition according to claim 1, wherein the number average molecular weight of the photopolymerizable composition is in the range of 100 to 10,000. 3. The epoxy-modified butadiene resin (a)
The photopolymerizable composition according to claim 1 or 2, wherein is a hydrogenated product. 4. The epoxy-modified butadiene resin (a)
A cationically polymerizable organic substance (b) other than bisphenol A type epoxy resin and its modified product, hydrogenated bisphenol A type epoxy resin and its modified product, bisphenol F
And at least one member selected from the group consisting of hydrogenated bisphenol F type epoxy resins and modified products thereof, novolak phenol resins and modified products thereof, alicyclic epoxy resins and modified products thereof. 1 to
4. The photopolymerizable composition according to any one of 3.