JPH0471401B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a photopolymerizable composition, and more particularly, to a photopolymerizable composition containing a specific aromatic ketone compound as a photopolymerization initiator. It is known that polymerization can be carried out by adding a suitable photopolymerization initiator to an unsaturated monomer or unsaturated polymer (prepolymer) and irradiating it with light, and many compounds are used for this purpose. It has been developed and proposed as a drug. Among these photopolymerization initiators, aromatic ketones such as benzophenone are widely used because they are inexpensive and have good solubility in unsaturated compounds. However, these initiators that have been used conventionally have disadvantages such as coloring the polymer, their small effect, and the need to use large amounts or irradiate them with light for a long time. Another drawback was that photopolymerizable compositions containing the initiator could not be stored for long periods of time. In view of the above-mentioned current situation, the inventors of the present invention have conducted intensive studies and found that the aromatic ketone compound represented by the following general formula () has an extremely large effect as a photopolymerization initiator, and that It has been found that polymerization can be allowed to proceed until required and does not impart color to the polymer. Furthermore, the photopolymerizable composition containing the aromatic ketone compound represented by the following general formula () has excellent storage stability and has the advantage that it does not deteriorate even when stored for a long period of time. I found out. The present invention was made based on the above findings, and
The present invention provides a photopolymerizable composition comprising a compound having at least one ethylenically unsaturated double bond and an aromatic ketone compound represented by the following general formula (). (In the formula, R ₁ is a hydrogen atom, a halogen atom, or

[Formula], R ₂ represents a hydrogen atom, an alkyl group, or an acyl group, R ₃ represents a hydrogen atom,
It represents a halogen atom, an alkyl group or _-COOR4 , and _R4 represents a hydrogen atom or an alkyl group. ) The photopolymerizable composition of the present invention will be explained in detail below. The aromatic ketone compound represented by the general formula () functions as a photopolymerization initiator, and the halogen atoms represented by R ₁ and R ₃ include chlorine, bromine, fluorine, and iodine, and R ₂ , R ₃ and
Alkyl groups represented by R ₄ include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tertiary-butyl, isobutyl, amyl, hexyl, octyl, isooctyl, 2-ethylhexyl, nonyl, decyl, dodecyl, tridecyl, and tetradecyl. , hexadecyl, octadecyl, etc., and examples of the acyl group represented by R ₂ include acetyl, propionyl, butyroyl, 2-ethylhexanoyl, dodecanoyl, acryloyl, methacryloyl, benzoyl, chlorobenzoyl, toluoyl, tert-butylbenzoyl, etc. It will be done. Representative examples of the compound represented by the general formula () include the following compounds. Among these aromatic ketone compounds, compounds in which R ₂ is a hydrogen atom or an alkyl group are particularly preferred because of their remarkable effects. Some of the above aromatic ketone compounds are known compounds, and other compounds can also be produced by known methods. For example, it can be easily produced by reacting a carbazole or a substituted carbazole with a benzoyl chloride or an aromatic acid anhydride, followed by N-alkylation or N-acylation as necessary. Next, a specific synthesis example of the aromatic ketone compound represented by the general formula () used in the present invention will be given. Synthesis example 1 (Synthesis of No. 1 compound) Carbazole 16.7g, benzoin chloride 15
While stirring the mixture at room temperature, 15 g of anhydrous aluminum chloride was added in three portions at intervals of 10 minutes to a mixture of g and 100 ml of tetrachloroethane.
After stirring at room temperature for 2 hours, the mixture was heated and stirred at 60° C. for 3 hours. After cooling, the blue-green colored reaction mixture was poured into a mixture of 50 g of ice and 50 g of concentrated hydrochloric acid with stirring, and stirring was continued for 1 hour. Next, add 100 ml of chloroform and transfer the organic layer to a separating funnel.
Washing with water was repeated several times, drying with anhydrous sodium carbonate, filtration, and then solvent removal. This colored residue after solvent removal was recrystallized twice from toluene, and the desired product (melting point 207-210℃) was obtained as pale yellow crystals.
I got it. Synthesis Example 2 (Synthesis of Compound No. 3) Synthesis Example 1 was added to a mixture of 11.2 g of N-n butylcarbazole, 8 g of benzoin chloride, and 50 ml of tetrachloroethane while stirring the mixture at room temperature.
Similarly, 8 g of anhydrous aluminum chloride was charged in three portions, and stirring was continued at room temperature for 8 hours. Synthesis example 1
In the same manner as above, the mixture was treated with ice-hydrochloric acid, washed with water, dried, and desolvated to obtain a viscous blue liquid (residue from desolvation). Next, 1% activated carbon and 100 ml of ethanol were added to the solvent-removed residue, treated on a water bath for 1 hour, filtered while hot, and the filtrate was collected as colorless crystals of the desired product (melting point 127~
129°C). Synthesis Example 3 (Synthesis of Compound No. 4) Add anhydrous chloride to a mixture of 11.2 g of N-n-butylcarbazole, 7.5 g of phthalic anhydride, and 50 ml of tetrachloroethane in the same manner as in Synthesis Example 1 while stirring the mixture at room temperature. 16 g of aluminum was charged in three portions, and stirring was continued at room temperature for 12 hours. In the same manner as in Synthesis Example 1, the mixture was treated with ice-hydrochloric acid, washed with water, dried, and the solvent was removed. Add 100ml of ethanol and 3 sulfuric acid to this removed solvent residue.
The mixture was added dropwise to perform an esterification reaction on a water bath for 6 hours, then added to a large amount of toluene, washed with water, dried, and the solvent removed to obtain the desired product as a slightly yellow viscous liquid. Synthesis Example 4 (Synthesis of Compound No. 8) 3-benzoylcarbazole obtained in Synthesis Example 1
5.4 g was dissolved in 30 ml of acetone, 1.2 g of potassium hydroxide and 1 g of water were added thereto, and the mixture was stirred at room temperature for 1 hour. Then, 3.3 g of 2-ethylhexylic acid chloride was added dropwise, and the mixture was stirred under reflux for 4 hours. After cooling, the reaction mixture was poured into a large amount of cold water and extracted three times with toluene, followed by washing with water, drying, and desolvation to obtain a dark red viscous liquid (residue after desolvation). Hexane was added to this solvent-removed residue, the precipitated end-reacted 3-benzoylcarbazole was removed by filtration, the hexane solution was allowed to stand overnight, and the precipitated white crystals were washed with filtered hexane to obtain the desired product (melting point 111-113 °C) was obtained. Synthesis Example 5 (Synthesis of Compound No. 11) 14 g of N-n-octylcarbazole, 16 g of benzoyl chloride, and 100 ml of tetrachloroethane
While stirring the mixture at room temperature, 16 g of anhydrous aluminum chloride was charged in four portions, and the mixture was stirred at room temperature for 6 hours and at 60-70°C for 4 hours. After cooling, the mixture was treated with ice-hydrochloric acid, washed with water, dried, and solvent removed in the same manner as in Synthesis Example 1. This desolvation residue was dissolved in toluene, 1% activated carbon was added thereto, treated on a water bath for 1 hour, filtered while hot, and the filtrate was desolvated.
This solution was allowed to stand overnight, and the precipitated crystals were filtered to obtain the desired product as colorless crystals (melting point: 164-166°C). The effect can be further enhanced by using various organic amine compounds in combination with the aromatic ketone compound represented by the general formula () used in the present invention. Examples of these organic amine compounds include:
Triethanolamine, triisopropanolamine, methyldiethanolamine, octyldiethanolamine, dodecyldiethanolamine,
Octadecyldiethanolamine, dibutylethanolamine, dioctylethanolamine, methyl-hydroxyhexyloctanolamine,
Diethanolaniline, diethanolamine, methylethanolamine, butylethanolamine, dodecylethanolamine, tetrahydroxyethylethylenediamine, tetrahydroxyethylhexamethylenediamine, triethylamine, tributylamine, dimethylaminopropylamine, dimethylaniline, diethylamine, dibutylamine, dioctylamine, Examples include tetramethylethylenediamine and Michler's ketone, but alkanolamines are particularly preferred because of their great effects. The compound having at least one ethylenically unsaturated double bond used in the present invention cures by addition polymerization when the photopolymerizable composition is irradiated with actinic rays, resulting in a cured product that becomes substantially insolubilized. It is a monomer to give or a polymer having an ethylenically unsaturated double bond in the side chain or main chain. Such compounds include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, and fumaric acid; esters of the unsaturated carboxylic acids and monohydric or polyhydric alcohols, or monohydric or polyhydric amines. (meth)acrylates of polyhydroxy esters obtained from polyhydric carboxylic acids and polyhydric alcohols; unsaturated polyesters or unsaturated polyamides obtained from unsaturated dicarboxylic acids (and other dicarboxylic acids) and polyhydric amines; ;Urethane acrylate obtained by reacting a urethane compound having terminal isocyanate obtained from diisocyanate and polyhydric alcohol with hydroxyalkyl (meth)acrylate;By reacting polyglycidyl ether of bisphenols or polyol with (meth)acrylic acid. Epoxy acrylate obtained; Linear polyester obtained by reacting dicarboxylic anhydride with glycidyl (meth)acrylate; Di( Examples include meth)acrylic modified polyester and polyamide. In these compounds, monohydric or polyhydric alcohols include, for example, methanol, ethanol, butanol, allyl alcohol, octanol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, neopentyl glycol, 1,4-butanediol, 1 , 3-butanediol, 1,6-hexanediol, glycerin, trimethylolpropane, trimethylolethane, tris(2-hydroxyethyl)isocyanate, pentaerythritol, diglycerin, ditrimethylolpropane, dipentaerythritol, etc.; Examples of monovalent or polyvalent amines include ammonia, methylamine, butylamine, octylamine, diethylamine, dibutylamine, ethylenediamine, diethylenetriamine, piperazine,
Examples include 1,6-hexamethylene diamine and melamine; examples of polycarboxylic acids other than unsaturated dicarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, tetrahydrophthalic acid, succinic acid, and adipic acid. , sebacic acid and the like; examples of the diisocyanate include toluene diisocyanate, diphenylmethane diisocyanate, isocyanatomethylcyclohexane isocyanate, hexamethylene diisocyanate, isophorone diisocyanate and the like. Specific examples of the unsaturated carboxylic acid ester or amide having at least one ethylenically unsaturated double bond used in the present invention include methyl-, ethyl-, butyl-, isooctyl- or 2-hydroxyethyl-acrylate. , methyl- or ethyl-methacrylate, ethylene glycol diacrylate, triethylene glycol diacrylate, 1,4-butanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate,
Tris(2-hydroxyethyl)isocyanurate triacrylate, dipentaerythritol-
Tetra-hexaacrylate, glycerin diacrylate, triethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate,
Examples include ethylene glycol dicrotonate, diallyl maleate, bis(acryloyloxyethyl phenyl) propane, acrylamide, methacrylamide, ethylene bis acrylamide, hexamethylene bis acrylamide, methylene bis methacrylamide, and the like. In addition to the above compounds, examples of compounds having at least one ethylenically unsaturated double bond used in the present invention include diallyl phthalate, diallyl malonate, divinyl adipate, divinyl phthalate, vinyl acetate, isobutyl vinyl ether, and ethylene glycol. divinyl ether, styrene,
Acrylonitrile, triallyl isocyanurate, triallyl phosphate, etc. can also be used. In addition, the blending ratio in the photopolymerizable composition of the present invention is 0.1 to 20 parts by weight of the aromatic ketone compound represented by the general formula () per 100 parts by weight of the compound having at least one ethylenically unsaturated double bond. Parts by weight. The photopolymerizable composition of the present invention may further contain thermal polymerization inhibitors, colorants, plasticizers, surface protectants, smoothing agents, etc., if necessary. Examples of the thermal polymerization inhibitor include hydroquinone, p-methoxyphenol, pyrogallol, catechol, 2,6-di-tert-butyl-p-cresol, β-naphthol, and tert-butylhydroquinone. The above colorants include carbon black, yellow lead,
Titanium white, Milori blue, Chrome Vermilion,
Inorganic pigments such as Hansa Yellow, Benzidine Yellow, Vulcan Orange, Permanent Orange, Lake Red C, Brilliant Carmine B,
Examples include organic pigments such as rhodamine lake, eosin, phloxine, Victoria blue lake, phthalocyanine blue, phthalocyanine green, quinacridone red, and dioxazine violet, and dyes such as alkali blue toner and methyl violet. The photopolymerizable composition of the present invention is useful in a wide range of fields of application, and can be used, for example, in the preparation of printing plates such as lithographic plates, letterpress plates, and intaglio plates, photocurable inks, paints, printed circuit boards, adhesives, and the like. As an exposure light source that can be applied to the photopolymerizable composition of the present invention, general-purpose light sources such as a carbon arc, a high-pressure mercury lamp, a xenon lamp, a methane halide lamp, a tungsten lamp, an argon laser, a helium-cadmium laser, etc. can be used. Hereinafter, the present invention will be explained in more detail with reference to Examples. Example 1 Blend (parts by weight) Urethane acrylate (molecular weight 1500) (Shin Nakamura Chemical; NK Ester U-108A) 75 1,6-hexanediol diacrylate 25 N-methyldiethanolamine 1 Photoinitiator (Table 1) ) 0.5 After thoroughly kneading the above formulation, it was uniformly coated onto paper to a thickness of 50 μm using a bar coater. The paper coated with the above composition was placed under irradiation with a high-pressure mercury lamp (manufactured by Toshiba; H-400P) and exposed for 15 seconds (irradiation distance: 12 cm). Next, the cured state of this coating was examined by the pencil hardness method. The results are shown in Table-1.

【table】

[Table] Example 2 Formulation (parts by weight) Epoxy acrylate (molecular weight approximately 1500) (manufactured by Shin Nakamura Chemical; NK Ester UVX-2) 80 Trimethylolpropane triacrylate 20 Titanium dioxide 70 N-methyldiethanolamine 6 Photoinitiator (Table 2) 6 After thoroughly kneading the above blend, it was uniformly coated onto paper to a thickness of 10 μm using a bar coater. The paper coated with the above formulation was placed under irradiation with a high-pressure mercury lamp (manufactured by Toshiba; H-400P) and exposed for 30 seconds (irradiation distance: 15 cm). Next, the cured state of this coating was examined by the pencil hardness method. The results are shown in Table-2.

[Table] Example 3 Compound (parts by weight) Urethane acrylate (molecular weight 1500) (Shin Nakamura Chemical; NK Ester U-108A) 80 Trimethylolpropane triacrylate 20 Carbon black 18 N,N'-tetraethyl-4,4 '-Diaminobenzophenone 4 Photopolymerization initiator (Table 3) 7 The above mixture was thoroughly kneaded and then coated uniformly onto paper to a thickness of 10 μm using a bar coater. The paper coated with the above formulation was placed under irradiation with a high-pressure mercury lamp (manufactured by Toshiba; H-400P) and exposed for 30 seconds (irradiation distance: 15 cm). Next, the cured state of this coating was examined by the pencil hardness method. The results are shown in Table-3.

[Table] Example 4 1 mol of terephthalic acid, propylene glycol
An unsaturated polyester was produced by heating and esterifying 3.3 moles of maleic anhydride and 2 moles of maleic anhydride. 55 parts by weight of the above unsaturated polyester and styrene
2 parts by weight of a photopolymerization initiator (Table 4) was added to 45 parts by weight, and the mixture was stored in a dark place at 60°C, and the number of days until a gel was formed was observed. The results are shown in Table 4.

【table】

Claims (1)

[Scope of Claims] 1. A photopolymerizable composition comprising a compound having at least one ethylenically unsaturated double bond and an aromatic ketone compound represented by the following general formula (). (In the formula, R ₁ represents a hydrogen atom, a halogen atom, or [Formula], R ₂ represents a hydrogen atom, an alkyl group, or an acyl group, and R ₃ represents a hydrogen atom, a halogen atom, an alkyl group, or -COOR ₄ . ,
R ₄ represents a hydrogen atom or an alkyl group. )