JP2000347001A - Photopolymerizable composition and hard coat agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photopolymerizable composition having extremely small shrinkage upon curing, which is a cause of curling, and therefore having excellent adhesion, and excellent transparency, abrasion resistance and solvent resistance. Provide a hard coat agent. SOLUTION: An essential component is 100 parts by weight of an energy ray polymerizable material, and an average particle diameter of 1 to 500 parts by weight in terms of SiO _{2 with} respect to the energy ray polymerizable material.
Contains colloidal silica dispersed in a 200 nm organic solvent.

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 a hard coat agent, and more particularly, to a cured film having excellent transparency and excellent abrasion resistance, adhesion and solvent resistance after a photopolymerization reaction. And a hard coat agent for coating the surface of a plastic material.

[0002]

2. Description of the Related Art Generally, engineering plastics are widely used as substitutes for glass and metal because of their light weight, easy moldability and low cost. However, these have a problem that they are easily damaged and their surfaces are easily eroded by various solvents.

[0003] Conventionally, in order to eliminate these obstacles in engineering plastics, the surface of such plastics has been protected with an energy ray-curable resin paint having high hardness.

[0004] However, as market demands have increased,
Higher surface hardness is required, and it has been necessary to further increase the hardness of the surface protective film.

The easiest way to increase the hardness of the surface protective film with the energy ray-curable resin is to increase the crosslink density, but in this case, the internal stress remaining inside the cured film at the end of curing is large. A new problem that the adhesiveness is deteriorated due to the influence has newly arisen. Therefore, at present, there is no resin that can achieve both high hardness and good adhesion properties to various plastic surfaces.

Further, when an energy ray-curable resin having an increased crosslink density and a higher surface hardness is used as a protective material for a thin plastic film surface as described above, the plastic film curls as a result of large curing shrinkage. there were.

As a means for increasing the surface hardness of a cured film, an energy ray-curable resin obtained by blending colloidal silica with an acrylic resin has been developed. For example, JP-A-6-41467, JP-A-6-92011, JP-A-6-2011
-100799, JP-A-6-41468 and JP-A-6
-287470, JP-A-6-100797, JP-A-7-41732, JP-A-7-109355, JP-A-7-207190, JP-A-7-247383, JP-A-7-2588582, JP-A-7- 331179, JP-A-8-325474, JP-A-8-259719,
JP-A-8-209006, JP-A-9-157315
JP-A-9-194760, JP-A-10-6030
7, JP-A-10-95951, JP-A-10-818
No. 39, JP-A-10-287824 and the like disclose an energy ray-curable resin obtained by mixing colloidal silica with a specific (meth) acrylic resin.

However, these techniques do not provide any improvement in the reduction of the shrinkage of the (meth) acryloyl group during the polymerization, and the adhesion of the substrate is still insufficient due to the presence of a large internal stress at the time of curing. Alternatively, problems such as curling of a plastic film remain.

[0009]

Accordingly, an object of the present invention is to reduce the shrinkage at the time of curing, which is the cause of the above-described curl, and therefore to provide excellent adhesion, transparency, abrasion resistance and solvent resistance. Another object of the present invention is to provide an excellent photopolymerizable composition and a hard coat agent.

[0010]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that the above object can be achieved by employing the following constitution as a photopolymerizable composition. The present invention has been completed.

That is, the photopolymerizable composition of the present invention comprises, as essential components, 100 parts by weight of an energy-ray-polymerizable material and 1 to 500 parts by weight of the energy-ray-polymerizable material in terms of SiO _2. The organic solvent-dispersed colloidal silica having a particle diameter of 5 to 200 nm is contained.

In the photopolymerizable composition of the present invention, the energy ray polymerizable material comprises (1) a cationic polymerizable organic substance and (2) an energy ray sensitive cationic polymerization initiator, or The energy ray polymerizable material is (1) a cationic polymerizable organic substance, (2) an energy ray sensitive cationic polymerization initiator, (3) a radical polymerizable organic substance, and (4) an energy ray sensitive radical polymerization initiator. Is preferred. In this case, the weight ratio (1) :( 3) of the (1) cationically polymerizable organic substance and the (3) radically polymerizable organic substance in the energy ray polymerizable material is preferably from 1 to 100: 0 to 99. is there.

The hard coat agent for coating the surface of a plastic material of the present invention is characterized by using these photopolymerizable compositions.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The organic solvent-dispersed colloidal silica used in the present invention is obtained by dispersing silica particles in an organic solvent.

The organic solvent used here is not particularly limited. Examples thereof include ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone, alcohol solvents such as methanol, ethanol and isopropanol, benzene, and the like. BTX solvents such as toluene and xylene, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, cellosolve solvents such as ethylene glycol monobutyl ether, methyl acetate,
Ester solvents such as ethyl acetate, carbitol solvents,
And the like. These organic solvents can be used as one kind or a mixture of two or more kinds, preferably an organic solvent having a boiling point of 200 ° C. or less, and a water content of 5% or less. It is desirable that the content be not more than weight%.

The content of silica in the organic solvent is optional.
SiO in proportion to the energy ray polymerizable material described below
₂ is not particularly limited as long as the content is within a desired range, but preferably contains 1 to 60% by weight of SiO ₂ .

If the content of SiO ₂ is too small, it is difficult to obtain a high-hardness film, and if it is too large, colloidal silica tends to be unstable.

The average particle diameter of the SiO ₂ dispersed in the organic solvent is 5 to 200 nm, more preferably 5 to 100 nm. When the average particle diameter is less than 5 nm, stable colloidal state cannot be maintained, and the stability of the compounded energy ray polymerizable composition is deteriorated. On the other hand, when the thickness exceeds 200 nm, the transparency of the cured film deteriorates, and the transparency which is a feature of the present invention becomes inappropriate.

The organic solvent-dispersed colloidal silica used in the present invention requires that the silica particles be dispersed in an organic solvent in a colloidal state, and is used as a dispersion. By centrifugation for 30 minutes, the sediment was 5% by weight of the SiO ₂ content.
It is preferred to use the following stable dispersions.

Such an organic solvent-dispersed colloidal silica cannot be obtained simply by dispersing SiO ₂ powder in the aforementioned organic solvent. When a material obtained by simply dispersing SiO ₂ powder is used, a composition having excellent transparency cannot be obtained because the dispersed particles greatly deviate from the above-mentioned particle size range.

The organic solvent-dispersed colloidal silica usable in the present invention can be obtained, for example, by solvent exchange of water-dispersed colloidal silica or hydrolysis of ethyl silicate. In addition, it is also possible to use general commercial products as they are, and use Adelite (Asahi Denka Kogyo Co.
), Snowtex (manufactured by Nissan Chemical Co., Ltd.) and Cataroid (manufactured by Catalysis Kasei Co., Ltd.).

The surface silanol groups of the colloidal silica can be modified by a silane coupling agent such as alkoxysilane or a titanate coupling agent such as alkoxytitanium.

The reaction of the surface silanol groups includes a reaction caused by a dehydration condensation reaction between the hydroxyl groups and carboxyl groups of the dispersing solvent and the surface silanol groups under high temperature and pressure.

[0024] The photopolymerizable composition of the present invention comprises an energy ray
The above-mentioned average particle size of 5 to 100 parts by weight of the polymerizable material is used.
200 nm organic solvent-dispersed colloidal silica was
O₂ It contains 1 to 500 parts by weight in conversion.

If the amount of colloidal silica is less than the above amount, the surface hardness of the film cured by the energy beam becomes insufficient, and if the amount exceeds the above amount, the cured coating film becomes opaque and becomes unsuitable.

The energy ray polymerizable material used in the present invention comprises (1) a cationic polymerizable organic substance and (2) an energy ray sensitive cationic polymerization initiator, or the above (1), (2) In addition, (3) a radically polymerizable organic substance and (4) an energy ray-sensitive radical polymerization initiator can be used.

The (1) cationically polymerizable organic substance that can be used for the energy ray polymerizable material includes, for example, epoxy compounds, cyclic ether compounds, oxetane compounds,
Examples thereof include a cyclic lactone compound, a cyclic acetal compound, a cyclic thioether compound, a spiro orthoester compound, and a vinyl compound, and one or more of these can be used. 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, such as bisphenol A and bisphenol F, and furthermore an alkylene oxide. Glycidyl ether, epoxy novolak resin, epoxidized fluorene resin, epoxidized carbazole resin and the like.

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 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 tall hexaglycidyl ether, polyethylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether. Further, polyglycidyl ethers of polyether polyols obtained by adding one or more alkylene oxides to aliphatic polyhydric alcohols such as propylene glycol and glycerin, and diglycidyl esters of aliphatic long-chain dibasic acids can be mentioned. Can be 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, epoxidized polybutadiene, and the like.

(1) Specific examples of cationically polymerizable organic substances other than epoxy compounds include trimethylene oxide, 3,3-dimethyloxetane, 3,3-dichloromethyloxetane, 3-methyl-3-hydroxymethyloxetane, Oxetane compounds such as 3-ethyl-3-hydroxymethyloxetane and 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene; oxofuran compounds such as tetrahydrofuran and 2,3-dimethyltetrahydrofuran; trioxane; Acetal compounds such as 1,3-dioxolan, 1,3,6-trioxanecyclooctane, β-propiolactone, ε-
Cyclic lactone compounds such as caprolactone, ethylene sulfide, thiirane compounds such as thioepichlorohydrin,
Thietane compounds such as 1,3-propyne sulfide and 3,3-dimethylthiethane, cyclic thioether compounds such as tetrahydrothiophene derivatives, ethylene glycol divinyl ether, alkyl vinyl ether, 3,4-dihydropyran-2-methyl (3, 4-dihydropyran-2
-Carboxylate), vinyl compounds such as triethylene glycol divinyl ether, spiro orthoester compounds obtained by reacting epoxy compounds with lactones, ethylenically unsaturated compounds such as vinylcyclohexene, isobutylene, polybutadiene, and derivatives of the above compounds. Can be

In the present invention, (1) one or more compounds of the above-mentioned cationically polymerizable substances can be blended and used as the cationically polymerizable organic substance.

Although not limited thereto, preferred among (1) cationically polymerizable organic substances are alicyclic epoxy resins having at least two or more epoxy groups per molecule, bisphenol A Epoxy resin, bisphenol F epoxy resin, epoxidized fluorene resin, and epoxidized carbazole resin.

The (2) energy ray-sensitive cationic polymerization initiator which can be used for the energy ray polymerizable material is a compound capable of releasing a substance which initiates cationic polymerization by 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- .

[0035] 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 (Metalloid) which is the central atom of the halide complex.
And B, P, As, Sb, Fe, Sn, Bi, A
1, Ca, In, Ti, Zn, Sc, V, Cr, Mn,
Co or the like. 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 ) ⁻ , hexafluoroarsenate (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.

As the anion ^Bm- , tetrakis (pentafluorophenyl) borate can also be preferably used.

In the present invention, it is particularly effective to use an aromatic onium salt among such onium salts.
Among them, JP-A-50-151997 and JP-A-50-1
Aromatic halonium salts described in JP-A-58680, and VIA aromatics described in JP-A-50-151997, JP-A-52-30899, JP-A-56-55420, JP-A-55-125105 and the like. Group onium salt, JP-A-50
A VA-group aromatic onium salt described in JP-A-1558698;
JP-A-56-8428, JP-A-56-149402
And oxosulfoxonium salts described in JP-A-57-192429, aromatic diazonium salts described in JP-A-49-17040, and thiobrillium salts described in U.S. Pat. No. 4,139,655 are preferred. Other preferable examples include an iron / allene complex and an aluminum complex / photolytic silicon compound-based initiator.

Of 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. And a compound represented by the formula: (tolylcumyl) iodonium, bis (tertiarybutylphenyl) 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, 4- (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 hexafluoro Antimonate, 4- (2-chloro-4-benzoylphenylthio) phenylbis (4-hydroxyphenyl) sulfonium hexafluorophosphate,
(2-chloro-4-benzoylphenylthio) phenyl bis (4-hydroxyphenyl) sulfonium hexafluoroantimonate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, (tolylcumyl) iodonium hexafluorophosphate, (tolylcumyl )
Iodonium hexafluoroantimonate, (tolylcumyl) iodonium tetrakis (pentafluorophenyl) borate, bis (tertiarybutylphenyl) iodonium hexafluorophosphate, bis (tertiarybutylphenyl) iodonium hexafluoroantimonate, bis (tertiarybutylphenyl) Iodonium tetrakis (pentafluorophenyl) borate, benzyl-4-hydroxyphenylmethylsulfonium hexafluorophosphate, benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, benzyldimethylsulfonium hexafluorophosphate, benzyldimethylsulfonium hexafluoroantimonate, p -Chlorobenzyl-4-
Hydroxyphenylmethylsulfonium hexafluorophosphate, p-chlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 4-acetoxyphenyldimethylsulfonium hexafluorophosphate, 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-naphthylmethyltetra Methylenesulfonium hexafluoroantimonate, cinnamyldimethylsulfonium hexafluorophosphate, cinnamyldimethylsulfonium hexafluoroantimonate, cinnamyltetramethylenesulfonium hexafluorophosphate,
Cinnamyltetramethylenesulfonium hexafluoroantimonate, N- (α-phenylbenzyl) -2-
Cyanopyridinium hexafluorophosphate, N-
(Α-phenylbenzyl) -2-cyanopyridinium hexafluoroantimonate, 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.

The preferable amount of the (2) energy ray-sensitive cationic polymerization initiator used is 0.1 to 50% by weight based on 100 parts by weight of the cationically polymerizable organic substance.
More preferably, the content is adjusted to 1.0 to 20% by weight. If (2) the amount of the energy ray-sensitive cationic polymerization initiator is less than 0.1% by weight based on 100 parts by weight of the cationically polymerizable organic substance, the curing may be insufficient and the surface hardness may be insufficient. Is undesirably caused. Further, even if it is blended in an amount exceeding 50% by weight, various properties are not improved, and conversely, the adhesion to various bases after curing is lowered with the increase of the uncured energy ray-sensitive cationic polymerization initiator component. It is not preferable because it is easy.

The (3) radically polymerizable organic substance that can be used for the energy ray polymerizable material is preferably a compound having at least one or more unsaturated double bonds in one molecule.

Examples of such compounds include acrylate compounds, methacrylate compounds, allyl urethane compounds, unsaturated polyester compounds, styrene compounds and the like.

Among such radically polymerizable organic substances, compounds having a meth (acryl) group are preferred because they are easy to synthesize and obtain and easy to handle. For example, epoxy (meth) acrylate, urethane (meth) acrylate, polyester (meth) acrylate, polyether (meth) acrylate, and (meth) acrylate esters of alcohols may be mentioned.

Here, the epoxy (meth) acrylate is, for example, an acrylate obtained by reacting a conventionally known aromatic epoxy resin, alicyclic epoxy resin, aliphatic epoxy resin or the like with (meth) acrylic acid. It is. Among these epoxy acrylates, particularly preferred is an acrylate of an aromatic epoxy resin, in which a polyglycidyl ether of a polyhydric phenol having at least one aromatic nucleus or an alkylene oxide adduct thereof is reacted with (meth) acrylic acid. (Meta) obtained by reacting
Acrylate. For example, glycidyl ether obtained by reacting bisphenol A or an alkylene oxide adduct thereof with epichlorohydrin,
(Meth) acrylate obtained by reacting with (meth) acrylic acid, and (meth) acrylate obtained by reacting epoxy novolak resin with (meth) acrylic acid are exemplified. Preferred as urethane (meth) acrylates are (meth) acrylates obtained by reacting one or more hydroxyl-containing polyesters or hydroxyl-containing polyethers with hydroxyl-containing (meth) acrylates and isocyanates, (Meth) acrylates obtained by reacting the contained (meth) acrylic acid ester with isocyanates.

Preferred as the hydroxyl group-containing polyester used here is a hydroxyl group-containing polyester obtained by reacting one or more polyhydric alcohols with one or more polybasic acids, Examples of the aliphatic polyhydric alcohol include 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol,
Neopentyl glycol, polyethylene glycol, polypropylene glycol, polybutylene glycol, trimethylolpropane, glycerin, pentaerythritol, dipentaerythritol and the like can be mentioned. Examples of the polybasic acid include adipic acid, terephthalic acid, phthalic anhydride, trimellitic acid and the like.

Preferred as the hydroxyl group-containing polyether are hydroxyl group-containing polyethers obtained by adding one or more alkylene oxides to a polyhydric alcohol. The same thing can be illustrated. Examples of the alkylene oxide include ethylene oxide, propylene oxide, and butylene oxide.

Preferred as the hydroxyl group-containing (meth) acrylic acid ester is a hydroxyl group-containing (meth) acrylic acid ester obtained by an esterification reaction between a polyhydric alcohol and (meth) acrylic acid. The same compounds as those described above can be exemplified.

Among such hydroxyl group-containing (meth) acrylic acids, a hydroxyl group-containing (meth) acrylate obtained by an esterification reaction between a dihydric alcohol and (meth) acrylic acid is particularly preferred, for example, 2-hydroxyethyl (meth) acrylate. A) acrylate.

As the isocyanates, compounds having at least one isocyanate group in the molecule are preferable, and isocyanates such as tolylene diisocyanate, hexamethylene diisocyanate and isophorone diisocyanate.
Valent isocyanate compounds are particularly preferred.

The preferred polyester (meth) acrylate is a polyester (meth) obtained by reacting a hydroxyl group-containing polyester with (meth) acrylic acid.
Acrylate. Preferred as the hydroxyl group-containing polyester used here is a hydroxyl group-containing polyester obtained by an esterification reaction of one or more polyhydric alcohols with one or more monobasic acids or polybasic acids. As the polyhydric alcohol, those similar to the aforementioned compounds can be exemplified. Examples of the monobasic acid include formic acid, acetic acid, butyric acid, and benzoic acid.
Examples of polybasic acids include adipic acid, terephthalic acid,
Examples include phthalic anhydride and trimellitic acid.

Preferred as the polyether (meth) acrylate is a polyether (meth) acrylate obtained by reacting a hydroxyl group-containing polyether with meth (acrylic) acid. Preferred as the hydroxyl group-containing polyether to be used here is one of polyhydric alcohols.
A hydroxyl-containing polyether obtained by adding one or more alkylene oxides,
Examples of the polyhydric alcohol include the same compounds as those described above. Examples of the alkylene oxide include ethylene oxide, propylene oxide, and butylene oxide.

Preferred as (meth) acrylic acid esters of alcohols are aromatic or aliphatic alcohols having at least one hydroxyl group in the molecule, and an alkylene oxide adduct thereof reacted with (meth) acrylic acid. (Meth) acrylate obtained by, for example, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, isoamyl (meth) acrylate, lauryl (meth) acrylate, Stearyl (meth) acrylate, isooctyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobonyl (meth) acrylate, benzyl (meth) acrylate, 1,3-butanediol di (meth)
Acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate,
Neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, ethylene oxide-modified trimethylolpropane tri (meth) acrylate, propylene oxide-modified tri Methylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ε-caprolactone-modified dipentaerythritol hexa (meth) acrylate,
Examples thereof include fluorene derivative di (meth) acrylate and carbazole derivative di (meth) acrylate. One or more of these radically polymerizable organic substances can be used in combination according to desired performance.

(4) The energy ray-sensitive radical polymerization initiator which can be used for the energy ray-polymerizable material includes:
It is a compound capable of initiating radical polymerization by energy irradiation, and is preferably a ketone-based compound such as an acetophenone-based compound, a benzyl-based compound, a benzophenone-based compound, and a thioxanthone-based compound.

Examples of the acetophenone compounds include diethoxyacetophenone and 2-hydroxy-2-
Methyl-1-phenylpropan-1-one, 4'-isopropyl-2-hydroxy-2-methylpropiophenone, 2-hydroxymethyl-2-methylpropiophenone, 2,2-dimethoxy-1,2-diphenyl Ethane
1-one, p-dimethylaminoacetophenone, p-tert-butyldichloroacetophenone, p-tert-butyltrichloroacetophenone, p-azidobenzalacetophenone, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1- [4- ( Methylthio) phenyl] -2-morpholinopropanone-1, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, Benzoin-n-butyl ether, benzoin isobutyl ether and the like.

Examples of the benzyl compound include benzyl, anisyl and the like.

Examples of the benzophenone compound include benzophenone, methyl o-benzoylbenzoate, Michler's ketone, 4,4'-bisdiethylaminobenzophenone, 4,4'-dichlorobenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide and the like. No.

Examples of the thioxanthone compound include thioxanthone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, and 2,4-diethylthioxanthone.

One or more of these (4) energy ray-sensitive radical polymerization initiators can be used in combination according to the desired performance.

The above (4) energy ray-sensitive radical polymerization initiator is preferably used in an amount of 0.05 to 10% by weight, more preferably 0.1 to 10% by weight, based on (3) the radically polymerizable organic substance. %. If it exceeds this range, sufficient strength may not be obtained, and if it is below this range, the resin may not be sufficiently cured.

The photopolymerizable composition containing the above-mentioned (3) radically polymerizable organic substance and (4) an energy ray-sensitive radical polymerization initiator has a greater effect than the case where these are not used.
The curing speed upon irradiation with energy rays is further increased, which is preferable.

In the energy ray polymerizable material, (1)
The weight ratio (1) :( 3) of the cationically polymerizable organic substance and (3) the radically polymerizable organic substance is preferably from 1 to 100: 0 to 99. (1) When the content of the cationically polymerizable organic substance is less than 1% by weight, that is, when the content of the radically polymerizable organic substance (4) is more than 99% by weight, the adhesion to various types of bases deteriorates. Therefore, at least 1% by weight or more of the cationically polymerizable organic substance (2) is preferably contained in the total amount of the energy ray-curable organic substance.
More preferably, the cationically polymerizable organic substance (2) should be contained in an amount of 10% by weight or more in the total amount of the energy ray-curable organic substance.

The energy ray polymerizable material used in the present invention can be used together with an organic compound having two or more hydroxyl groups in one molecule, if necessary. For example, two molecules per molecule of a polyhydric alcohol, a hydroxyl group-containing polyether, a hydroxyl group-containing polyester, a polyhydric phenol, etc.
By blending an organic compound having at least two hydroxyl groups, the mechanical strength of the cured coating film can be increased.

Examples of polyhydric alcohols include ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, glycerin, pentaerythritol, dipentaerythritol, 1,3-butanediol, 1,4-butanediol, 1,6-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 polyphenols. 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 phenols with one or more monobasic acids or polybasic acids. And a hydroxyl-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.

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

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 the photopolymerizable composition of the present invention requires position selectivity for polymerization and curing, a laser beam having a good light-collecting property (particularly, 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 derived from the fact that the cured film after photopolymerization has excellent transparency, has extremely high surface hardness and abrasion resistance, and has small curing shrinkage during the curing treatment. Since the internal residual stress is small, it is particularly useful as a surface protective agent for substrates such as various engineering plastics.

Such a substrate is not particularly limited, but examples thereof include a poly-α-olefin resin,
Examples thereof include synthetic resin base materials such as polyester resin, epoxy resin, polyamide resin, polyurethane resin, polyimide resin, polyurea resin, and polycarbonate resin.

The photopolymerizable composition of the present invention is preferably applied to a substrate so as to have a thickness of 0.5 to 100 μm, preferably 1 to 100 μm, more preferably 1 to 30 μm. If the thickness exceeds 100 μm, the cured coating film tends to be easily cracked, and if the thickness is less than 0.5 μm, sufficient hardness cannot be exhibited, which is inappropriate.

[0075]

Next, the present invention will be described with reference to examples. 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 below. The evaluation method in the present invention is described below.

Preparation of test piece: A polyethylene terephthalate film (easy adhesion P
(Abbreviated as ET), a test resin diluted to a solid content of 50% by weight was applied so as to have a dry film thickness of 5 μm, and irradiated with an ultraviolet ray having an irradiation amount of 100 mJ / cm ² by a high-pressure mercury lamp to cure the photopolymerizable composition. This was used as a test piece. Transparency of cured film: The transmittance (%) and turbidity of the test piece were measured. Surface hardness: Evaluated according to the pencil scratch test method described in JIS K5400 6.14. Abrasion resistance: An abrasion test was performed 20 times with a load of 250 g using a taper abrasion tester. The degree of surface damage before and after the abrasion test was evaluated by turbidity of transmitted light (HAZE). Adhesion: In the method of preparing the test piece, the coating base was a polyethylene film (abbreviated as PE), a polycarbonate film (abbreviated as PC), a vinyl chloride resin film (abbreviated as PVC), a polyimide film (abbreviated as PI), SUS30
4. Changed to blue sheet glass. JIS K5400 6.
A peel test was performed according to the grid test described in No. 15, and the adhesion was confirmed. Curing shrinkage: Except for using a 50 μm-thick surface easy-adhesion treatment PET, the method was the same as the method for preparing test pieces. The size of the film was set to 50 × 120 mm, and the amount of warpage (mm) in the long side direction after curing was measured. The degree of cure shrinkage was determined by the amount of sled rise. Solvent resistance: A cotton swab was impregnated with methyl ethyl ketone, and the cured coating was rubbed back and forth, and the number of reciprocations until the surface of the cured coating dissolved or changed to cloudiness was observed. The maximum number of reciprocations was 200 times.

The materials used in Tables 1 and 2 are as follows. Epoxy resin 1: 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate Epoxy resin 2: 1,6-hexanediol diglycidyl ether Acrylic resin 1: Dipentaerythritol hexaacrylate Acrylic resin 2: Trimethylolpropane tri Acrylate colloidal silica 1: ethyl cellosolve dispersion (SiO ₂
Content 30% by weight, average particle diameter 12 nm, water content 0.2% by weight) Colloidal silica 2: Isopropanol dispersion (SiO ₂
Content: 30% by weight, average particle diameter: 90 nm, water content: 0.6% by weight) Photocationic polymerization initiator: 4,4′-bis (di (β-hydroxyethoxy) phenylsulfonio) phenylsulfidobis-hexa Fluoroantimonate Photo-radical polymerization initiator: 1-hydroxycyclohexyl phenyl ketone

[0078]

[Table 1]

[0079]

[Table 2]

[0080]

According to the present invention, a photopolymerizable composition and a hard coat agent which have extremely small shrinkage upon curing, have excellent adhesion, and have excellent transparency, abrasion resistance and solvent resistance are obtained. be able to.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hiroyuki Tachikawa F-term (Reference) 2K009 CC09 CC24 CC33 DD02 DD05 EE00 within 7-35 Higashiogu, Arakawa-ku, Tokyo

Claims (5)

[Claims] An essential component is 100 parts by weight of an energy ray-polymerizable material and an average particle diameter of 1 to 500 parts by weight in terms of SiO _{2 with} respect to the energy ray-polymerizable material.
A photopolymerizable composition comprising an organic solvent-dispersed colloidal silica having a thickness of from 200 to 200 nm. 2. The method according to claim 1, wherein the energy ray polymerizable material is (1)
The photopolymerizable composition according to claim 1, comprising a cationically polymerizable organic substance and (2) an energy ray-sensitive cationic polymerization initiator. 3. The method according to claim 1, wherein the energy ray polymerizable material is (1)
The photopolymerizable composition according to claim 1, comprising a cationic polymerizable organic substance, (2) an energy ray-sensitive cationic polymerization initiator, (3) a radical polymerizable organic substance, and (4) an energy ray-sensitive radical polymerization initiator. Composition. 4. In the energy ray polymerizable material,
The weight ratio (1) :( 3) of (1) the cationically polymerizable organic substance to (3) the radically polymerizable organic substance is from 1 to 100: 0 to 9
The photopolymerizable composition according to claim 3, which is 9. 5. A hard coat agent for coating the surface of a plastic material, comprising using the photopolymerizable composition according to any one of claims 1 to 4.