JPH0769607B2 - Photopolymerizable composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a photopolymerizable composition containing an unsaturated monomer, a photopolymerization initiator, and, if necessary, a linear organic polymer. In particular, the present invention relates to a photopolymerizable composition capable of providing a photocured image useful for producing a printing original plate, a photoresist and the like.

[Conventional technology]

A photopolymerizable composition prepared by mixing a polymerizable ethylenically unsaturated compound, a photopolymerization initiator, and if necessary, a linear organic polymer having a proper film-forming ability, a thermal polymerization inhibitor, etc. A method of duplicating an image by a static method is currently widely known. That is, as described in JP-B-35-5093 and JP-B-35-8495,
Since the photosensitive composition undergoes photopolymerization by irradiation with actinic rays and is insolubilized, the photosensitive composition is formed into a suitable film, and the composition is irradiated with actinic rays through a negative image of a desired image, and then is irradiated with a suitable solvent. A desired photopolymerized image can be formed by removing only the unexposed area (hereinafter simply referred to as development). There is no argument that this type of photosensitive composition is extremely useful as a photosensitizer for printing plates or photoresists.

Conventionally, benzyl, benzoin, benzoin ethyl ether, Michler's ketone, anthraquinone, acridine, phenazine, benzophenone, 2-ethylanthraquinone, etc. are known as typical ones as photopolymerization initiators for polymerizable ethylenically unsaturated compounds. Has been. Among them, aromatic ketones such as benzophenone are widely used because they are inexpensive and have good solubility in unsaturated compounds.

Further, JP-A-54-99185 discloses an α-substituted aliphatic-aromatic ketone, JP-A-58-157805 discloses a sulfur-containing α-amino aliphatic aromatic ketone, JP-A-61-21104. The publication proposes an aliphatic aromatic ketone composed of a specific carbazole derivative. However, these photopolymerization initiators have the drawback that they are used in large amounts or require long-term photoirradiation because of their low photopolymerization initiation ability, and the photopolymerizable composition to which the initiator is added is It has not been sufficient yet, because it has the drawback of poor storage stability for a long period of time.

[Problems to be solved by the invention]

Therefore, an object of the present invention is to provide a photopolymerizable composition having high sensitivity and excellent storage stability.

[Means for Solving Problems] The above object of the present invention is achieved by using an aromatic ketone composed of a specific carbazole derivative in combination with a thioxanthene compound and, if necessary, an organic amine compound.

That is, the present invention provides a photopolymerization product containing a monomer having at least one ethylenically unsaturated group capable of photopolymerization by actinic rays, a photopolymerization initiator, and, if necessary, a linear organic polymer. In the polymerizable composition, at least one of the following general formulas (I), (II) or (III) as a photopolymerization initiator (In the formula, R ₁ and R ₂ each represent an alkyl group, and R ₁ and
R ₂ may be bonded to each other to represent an alkylene group, R ₃ represents a hydrogen atom, an alkyl group or an acyl group, and X ₁ represents —OR ₅
Or The stands, R ₅ represents a hydrogen atom, an alkyl group or alkenyl group, each of R ₆ and R ₇ represents an alkyl or hydroxyalkyl group, and R ₆ and R ₇ is an alkylene group bonded to each other, oxa dialkylene Represents a group or iminodialkylene group, Y ₁ is a hydrogen atom or , Y ₂ represents a hydrogen atom, a halogen atom or a nitro group, R ₄ represents a direct bond or an alkylene group, and X ₂ represents —O.
-R ₈ -O- or R ₈ represents an alkylene group, R ₉ represents an alkyl group, and two R ₉ may be bonded to each other to represent an alkylene group. ) And at least one of the following general formula (IV) (In the formula, Ar and Ar ′ represent a substituted or unsubstituted aryl group.) A photopolymerizable composition comprising a combination of compounds represented by the formulas and, if necessary, an organic amine compound.

The “monomer having at least one ethylenically unsaturated group capable of being photopolymerized by actinic rays” used in the present invention is
At least one in one molecule with a boiling point of 100 ° C or higher at normal pressure,
More preferably, it is a monomer or oligomer having a molecular weight of 10,000 or less and having two or more addition-polymerizable ethylenically unsaturated groups. Examples of such monomers include monofunctional acrylates and methacrylates such as polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, and phenoxyethyl (meth) acrylate; polyethylene glycol di (meth) acrylate, trimethylolethanetri (Meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate,
Pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (acryloyloxypropyl) ether, tri (acryloyloxyethyl) isocyanurate, glycerin and trimethylol A poly (meth) acrylate obtained by adding ethylene oxide or propylene oxide to a polyfunctional alcohol such as ethane.
Urethane acrylates as described in JP-A-48-41708, JP-B-50-6034 and JP-A-51-37193, JP-A-48-64183, JP-B-49-43191 and JP-B-52 -30490 Polyester acrylates described in each publication,
Examples thereof include polyfunctional acrylates and methacrylates such as epoxy acrylates obtained by reacting an epoxy resin with (meth) acrylic acid. Furthermore, Japan Adhesive Association magazine Vo
Also, those introduced as photocurable monomers and oligomers on pages 300 to 308 of No. 7, No. 7, can be used. The amount of these used is 5 to 50 with respect to all components.
% By weight (hereinafter abbreviated as%), preferably 10-40%
Is appropriate.

In the general formula (I), (II) or (III), R ₁ , R ₂ , R
Examples of the alkyl group represented by ₃ , R ₅ , R ₆ , R ₇ , and R ₉ include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, sec-butyl, isobutyl, amyl, hexyl, octyl, isooctyl. , 2-ethylhexyl, nonyl, decyl, dodecyl, tridecyl, tetradecyl, octadecyl and the like; examples of the alkylene group formed by combining R ₁ and R ₂ include tetramethylene, pentamethylene, hexamethylene, heptamethylene and the like. Examples of the acyl group represented by R ₃ include acetyl, propionyl, butyroyl, 2-ethylhexanoyl, acryloyl, methacryloyl, benzoyl, trioyl, tert-butylbenzoyl, chlorobenzoyl and the like;
Examples of the alkenyl group represented by R ₅ include allyl, octadecenyl and the like; examples of the hydroxyalkyl group represented by R ₆ and R ₇ include hydroxyethyl, 2-hydroxypropyl, 2-hydroxybutyl and the like. ; R ₆ and R ₇
Examples of the alkylene group, oxadialkylene group or iminodialkylene group formed by bonding with each other include tetramethylene, pentamethylene, hexamethylene, oxadiethylene, iminodiethylene; and the halogen atom represented by Y ₂ is , Chlorine, bromine, fluorine and iodine; examples of the alkylene group represented by R ₄ include methylene, ethylene, trimethylene, tetramethylene, hexamethylene and decamethylene, and examples of the alkylene group represented by R ₈ include Include methylene, propylene, 2,2-dimethylpropylene, 1,4-butylene, 1,6-hexamethylene, 1,10-decamethylene, and the like. The alkylene group formed by combining two R ₉ 's is , Methylene, ethylene, propylene, butylene and the like. Specific examples of such compounds include carbazole derivative initiators described in JP-A-61-21104, such as 3- (2).
-Methyl-2-dimethylaminopropionyl) -carbazole, 3- (2-methyl-morpholinopropionyl)
-9-methylcarbazole, 3,6-bis (2-methyl-
2-morpholinopropionyl) -9-methylcarbazole, 3,6-bis (2-methyl-2-morpholinopropionyl) -9-n-butylcarbazole, 3- (2-methyl-2-morpholinopropionyl) -9-butyl Carbazole, 3- (2-ethyl-2-piperidinopropionyl) -9-butylcarbazole, 3- (2-methyl-2)
-Diethanolaminopropionyl) -9-methylcarbazole, 3- (2-methyl-2-dibutylaminopropionyl) -6-chlorocarbazole, 3- (2-methyl-2-piperazinopropionyl) -6-nitro-9 −
Methylcarbazole, 3- (2-methyl-2-morpholinopropionyl) -9-acetylcarbazole, 3,6-
Bis (2-methyl-2-morpholinopropionyl) -9
-Benzoylcarbazole, 3- (2-methyl-2-hydroxypropionyl) -9-methylcarbazole, 3
-(2-Methyl-2-methoxypropionyl) -9-methylcarbazole, 3- (2-methyl-2-allyloxypropionyl) -9-methylcarbazole, 3- (1-
Hydroxycyclohexanoyl) -9-butylcarbazole, 1,4-bis (9-butyl-3-carbazolyl)-
2,3-Dihydroxybutane-1,4-dione, 1,6-bis (9-methyl-3-carbazolyl) -2,5-bis (diethylamino) hexane-1,6-dione, 1,4-bis [ 1-
(9-Methyl-3-carbazolyloyl) isopropyl]
Piperazine, N, N'-dimethyl-N, N'-bis "1- (9
-Methyl-3-carbazolyloyl) isopropyl] -ethylenediamine, 2,7-bis [1- (9-butyl-3-)
Carbazolyloyl) isopropyl] -2,7-dimethyl-
3,6-dioxaoctane and the like can be mentioned.

Examples of the compound represented by the general formula (IV) used in the present invention include U.S. Pat. No. 3,857,769 and German Patent 3,018,891.
No. 2,075,506, JP 57-23602, JP 57-163377, JP 57-104135, and JP 52-34490.
Examples thereof include thioxanthone and its derivatives described in JP-A-52-150446, JP-A-54-14489, European Patent No. 33720, and JP-A-59-139378. Among these (X ₁ represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, Y ₁ represents Cl, —CN, —COOH, —COOR ″, and R ″
Represents an alkyl group or an aryl group. ) The thioxanthone derivative represented by

The content concentration of these photopolymerization initiator systems in the composition of the present invention is usually low, and when the content is inappropriately high, undesired results such as blocking of effective rays are produced. The amount of photoinitiator system in the present invention is (I), (II) or (II
The total amount of the compound represented by I) and the compound represented by (IV) is 0.01% to the total of the photopolymerizable ethylenically unsaturated compound and the linear organic polymer if necessary.
A range of 20% is sufficient, more preferably 1% to 10%
And get good results. Further, the proportions of the general formula (I), (II) or (III) and the general formula (IV) with respect to the total photopolymerization initiator are preferably 80 to 20% and 20 to 80%, respectively.

Further, in the photopolymerizable composition of the present invention, various organic amine compounds can be used in combination, if necessary, whereby the sensitivity can be further increased. Examples of these organic amine compounds include triethanolamine, dimethylamine, diethanolaniline, p-dimethylaminobenzoic acid ethyl ester, Michler's ketone and the like. The addition amount of the organic amine compound is preferably about 50% to 200% of the total amount of the photopolymerization initiator.

Further, the photopolymerization initiator used in the present invention may optionally contain N-phenylglycine, 2-mercaptobenzothiazole, N,
The photopolymerization initiation ability can be further enhanced by adding a hydrogen donating compound such as an N-dialkylbenzoic acid alkyl ester.

Any linear organic high molecular polymer may be used as the linear organic high molecular polymer in the present invention as long as it is a linear organic high molecular polymer compatible with the photopolymerizable ethylenically unsaturated compound. However, it is desirable to select a linear organic polymer which is soluble or swellable in water or weak alkaline water, which enables water development or weak alkaline water development.

The linear organic high molecular polymer is used not only as a film forming agent for the composition but also as a developer for water, weak alkaline water or an organic solvent. For example, water development becomes possible by using a water-soluble organic high molecular polymer. Examples of such a linear organic high molecular polymer include an addition polymer having a carboxylic acid in a side chain, for example, a methacrylic acid copolymer,
There are acrylic acid copolymers, itaconic acid copolymers, crotonic acid copolymers, maleic acid copolymers, partially esterified maleic acid copolymers, and the like.
Benzyl (meth) acrylate / (meth) acrylic acid / another addition-polymerizable vinyl monomer copolymer as required, as described in JP-B No. 15-34; as described in JP-B-54-34327. Methacrylic acid / methyl methacrylate or ethyl / alkyl methacrylate copolymer;
Other Japanese Patent Publication No. 58-12577, Japanese Patent Publication No. 54-25957, JP-A-54
-(Meth) acrylic acid copolymers as described in JP-A-92723; allyl (meth) acrylate / (meth) acrylic acid / necessarily as described in JP-A-59-53836 Accordingly, other addition-polymerizable vinyl monomer copolymers, polymers obtained by adding pentaerythritol triacrylate to the maleic anhydride copolymer described in JP-A-59-71048 by half-esterification, and the like. In-
_{COOH, -PO 3 H 2, -SO} 3 has H, -SO ₂ NH _2, a -SO ₂ NHCO- group, it may be mentioned acidic vinyl copolymer oxidation 50-200.

Similarly, there is an acidic cellulose derivative having a carboxylic acid in the side chain. In addition to these, those obtained by adding a cyclic acid anhydride to an addition polymer having a hydroxyl group are useful. In addition, polyvinylpyrrolidone, polyethylene oxide and the like are useful as the water-soluble linear organic polymer. To increase the strength of the cured film, alcohol-soluble nylon or 2,2
Polyethers of -bis- (4-hydroxyphenyl) -propane and epichlorohydrin are also useful.

In particular, among these, benzyl (meth) acrylate / (meth) acrylic acid / optionally other addition-polymerizable vinyl monomer copolymer and allyl (meth) acrylate /
(Meth) acrylic acid / another addition-polymerizable vinyl monomer copolymer, if necessary, are suitable. The amount of linear polymer used is 10% to 90%, preferably 30%, based on the total composition.
~ 85%. The weight ratio of the ethylenic addition-polymerizable monomer and the linear high molecular weight polymer is preferably 0.5 / 9.5 to 5/5, more preferably 1/9 to 4/6. .

Further, in the present invention, in addition to the above basic components, a small amount of a thermal polymerization inhibitor is added to prevent unnecessary thermal polymerization of the polymerizable ethylenically unsaturated compound during the production or storage of the photosensitive composition. Is desirable. Suitable thermal polymerization inhibitors include hydroquinone, p-methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4'-thiobis (3-methyl-6-t-butylphenol). ), 2,
2'-methylenebis (4-methyl-6-t-butylphenol), 2-mercaptobenzimidazole, N-nitrosophenylhydroxyamine primary molium salt and the like can be mentioned. Depending on the case, a dye or pigment may be added for the purpose of coloring the photosensitive layer, an inorganic filler or other known additives may be added for the purpose of improving the physical properties of the cured film.

The photopolymerizable composition of the present invention is used by dissolving it in various organic solvents at the time of coating, and the solvent used here is acetone, methyl ethyl ketone, dichlorohexane, ethyl acetate, ethylene dichloride, tetrahydrofuran. , Toluene, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, propylene glycol monoethyl ether, propylene glycol monoethyl ether, acetylacetone, cyclohexanone, diacetone alcohol, ethylene glycol monomethyl ether acetate, ethylene glycol ethyl ether acetate, Ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether acetate, 2-methoxy ether Nol, 3-methoxypropanol, methoxymethoxyethanol, 2-methoxyethyl acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, 3-methoxypropyl There are acetate, N, N-dimethylformamide, dimethylsulfoxide, γ-butyrolactone and the like, and these solvents may be used alone or in combination. And, the concentration of the solid in the coating solution is preferably 2 to 50% by weight.

The coating amount in the range of about 0.1 g / m ² ~ about 10 g / m ² in weight after drying are suitable, more preferably from 0.5 to 5 g / m ^2.

As the above support, a dimensionally stable plate-like material is used. Such dimensionally stable plate-like materials include those conventionally used as a support for printing plates, and they can be preferably used. Examples of such a support include paper, paper laminated with plastic (eg, polyethylene, polypropylene, polystyrene, etc.), metal plate such as aluminum (including aluminum alloy), zinc, copper, etc., such as cellulose diacetate, Films of plastics such as cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc., paper on which the above metals are laminated or vapor deposited. Alternatively, a plastic film or the like is included. Among these supports, the aluminum plate is particularly preferable because it is dimensionally remarkably stable and inexpensive. Furthermore, Japanese Patent Publication 48-183
A composite sheet in which an aluminum sheet is bonded on a polyethylene terephthalate film as described in Japanese Patent No. 27 is also preferable.

Further, in the case of a support having a surface of metal, especially aluminum, it is subjected to surface treatment such as graining treatment, immersion treatment in an aqueous solution of sodium silicate, potassium fluorozirconate, phosphate, etc., or anodization treatment. Is preferred.

Further, as described in U.S. Pat.No. 2,714,066, an aluminum plate which has been grained and then dipped in an aqueous solution of sodium silicate, as described in Japanese Patent Publication No. 47-5125, is used as an anode. A product obtained by immersing it in an aqueous solution of an alkali metal silicate after the oxidation treatment is also suitably used. The anodizing treatment, for example,
Inorganic acids such as phosphoric acid, chromic acid, sulfuric acid, boric acid, etc., or organic acids such as oxalic acid, sulfamic acid, etc., or an aqueous solution or a non-aqueous solution of these salts, singly or in combination of two or more kinds, and an aluminum plate as an anode It is carried out by flowing.

Further, silicate electrodeposition as described in US Pat. No. 3,658,662 is also effective.

Furthermore, JP-B-46-27481, JP-A-52-58602,
It is also useful to use a combination of the electrolytic grained support as disclosed in JP-A-52-30503 and the anodizing treatment and the sodium silicate treatment.

Further, those subjected to mechanical roughening, chemical etching, electrolytic graining, anodic oxidation treatment and sodium silicate treatment in this order as disclosed in JP-A-56-28893 are also preferable.

After further performing these treatments, a water-soluble resin, for example, polyvinyl phosphonic acid, a polymer and a copolymer having a sulfonic acid group in the side chain, polyacrylic acid, a water-soluble metal salt (for example, zinc acetate), or Those undercoated with a yellow dye, an amine salt or the like are also suitable.

These hydrophilization treatments, in addition to the treatment for making the surface of the support hydrophilic, prevent the harmful reaction of the photopolymerizable composition provided thereon, and further improve the adhesion of the photosensitive layer. It is provided for improvement.

On the layer of the photopolymerizable composition provided on the support, in order to completely prevent the polymerization inhibiting action by oxygen in the air,
For example, a protective layer made of a polymer having an excellent oxygen barrier property such as polyvinyl alcohol and acidic celluloses may be provided. The coating method of such a protective layer is described in detail, for example, in US Pat. No. 3,458,311 and JP-B-55-49729.

The photosensitive plate provided with the photopolymerizable composition of the present invention on a support is imagewise exposed using a light source rich in ultraviolet rays such as a metal halide lamp, a high pressure mercury lamp, etc. The exposed portion is removed, and a gum solution is finally applied to obtain a printing plate. Preferable examples of the developing solution include the developing solutions described in JP-B-57-7427, and include sodium silicate, potassium silicate, sodium hydroxide, potassium hydroxide, lithium hydroxide, and third. Inorganic alkaline agents such as sodium phosphate, dibasic sodium phosphate, tribasic ammonium phosphate, dibasic ammonium phosphate, sodium metasilicate, sodium bicarbonate, aqueous ammonia, etc. and organic such as monoethanolamine or diethanolamine. Aqueous solutions of alkaline agents are suitable and are added so that their concentration is 0.1 to 10% by weight, preferably 0.5 to 5% by weight.

In addition, the alkaline aqueous solution may optionally contain a surfactant, benzyl alcohol, 2-phenoxyethanol, or 2
An alkaline aqueous solution containing a small amount of an organic solvent such as butoxyethanol, and examples thereof include those described in US Pat. Nos. 3,475,171 and 3,615,480.

Furthermore, JP-A-50-26601, JP-A-58-54341, and JP-B-56-394
The developing solutions described in JP-A Nos. 64 and 56-42860 are also excellent as the developing solution for the photosensitive printing plate.

The present invention is described below with reference to examples, but the present invention is not limited thereto.

Example 1 An aluminum plate having a thickness of 0.30 mm was grained on its surface with a nylon brush and an aqueous suspension of 400 mesh pumice, and then washed thoroughly with water. It was immersed in 10% sodium hydroxide at 70 ° C. for 60 seconds for etching, washed with running water, neutralized with 20% HNO ₃ , and then washed with water. This is V _A =
Electrolytic surface roughening treatment was carried out in a 1% nitric acid aqueous solution under a condition of 12.7 V in an aqueous 1% nitric acid solution at an anodic electricity of 160 clones / dm ² . When its surface roughness was measured, it was 0.
It was 6 μ (Ra indication). Next, after soaking in 30% H ₂ SO ₄ aqueous solution and desmutting at 55 ° C for 2 minutes, 20% H ₂ SO 4
₄ Anodizing treatment was performed for 2 minutes in an aqueous solution at a current density of 2 A / dm ^{2 to} a thickness of 2.7 g / m ² .

On the aluminum plate thus treated, a photosensitive solution having the following composition was applied so that the dry coating weight would be 1.5 g / m ^2, and 1
A photosensitive plate was obtained by drying at 00 ° C for 2 minutes.

Allyl methacrylate / methacrylic acid copolymer 3.2 g (copolymerization molar ratio 80/20) Pentaerythritol tetraacrylate 1.7 g Photoinitiator X g Methyl ethyl ketone 20 g Propylene glycol monomethyl ether acetate 20
g Fluorine-based nonionic surfactant 0.03 g [3M, Fluorad FC-430 (trade name)] 3% by weight of polyvinyl alcohol (saponification degree: 86.5 to 89 mol%, polymerization degree: 1000) was placed on this photosensitive plate. The aqueous solution was applied so that the dry coating weight would be 2 g / m ^2, and dried at 100 ° C. for 2 minutes.

Exposure is performed using a vacuum baking machine, Fuji Photo Film Co., Ltd. PS light S type (metal halide lamp, 2KW)
I went from a distance of 1m for 10 seconds. The sensitivity was measured using a Fuji PS step guide (manufactured by Fuji Photo Film Co., Ltd., a step tablet having a transmission optical density of 0.05 at the first step and increasing the transmission optical density by 0.15 for each step up to 15 steps). Development is 1K potassium silicate 30g, potassium hydroxide 15g, It was carried out by immersing it in a developing solution consisting of 3 g and 1000 g of water at 25 ° C. for 1 minute.

Table 1 shows the results of sensitivity when the combination of photopolymerization initiators was changed.

It can be seen from Table 1 that the sensitivity is dramatically increased in Example 1 which is a combination of Comparative Examples 1-1 and 1-2 containing only the initiator.

In addition, as a storage stability test, samples were stored at 55 ° C and 15%.
It was confirmed that the same sensitivity can be obtained even in the sample left in RH for 5 days and in 35 ° C., 85% RH for 5 days, and the storage stability is also excellent.

Example 2 A photosensitive plate was prepared in the same manner as in Example 1 except that the photosensitive solution having the following formulation was used.

[Photosensitive solution formulation]

Trimethylolpropane tri (acryloyloxypropyl) ether 2.0 g Allyl methacrylate / methacrylic acid copolymer 2.0 g (copolymerization molar ratio 80/20) Initiator X g 0.1g Copper phthalocyanine pigment 0.2g Fluorinated nonionic surfactant 0.03g [3M, Fluorad FC-430 (trade name)] Methyl ethyl ketone 20g Propylene glycol monomethyl ether acetate 20
g The dry coating amount of this photosensitive solution was 1.5 g / m ² . Example 1
In the same manner as above, an oxygen barrier layer made of polyvinyl alcohol was provided at 2.0 g / m ² on this photosensitive layer, exposed using the same exposure apparatus as in Example 1, and developed.

It can be seen from Table 2 that the sensitivity of the combined initiator system is higher than that of the combined initiator system (+ amine).

Further, when the storage stability test in Example 1 was conducted in the same manner, it was confirmed that the same sensitivity could be obtained and the storage stability was excellent.

Example 3 20% H ₂ SO ₄ in the production of the aluminum substrate of Example 1
Instead of anodizing in an aqueous solution, anodizing in a 5% aqueous solution of phosphoric acid for 2 minutes at a current density of 2 A / dm ² to 0.8 g / m ² and then a 3% aqueous solution of sodium silicate. Using a substrate treated at 70 ° C. for 10 seconds, a photosensitive plate was prepared according to the following photosensitive solution formulation.

[Photosensitive solution formulation]

Pentaerythritol tetraacrylate 1.5g Benzyl methacrylate / methacrylic acid copolymer 3.
0 g (copolymerization molar ratio 65/35) Disclosing agent X g Copper phthalocyanine pigment 0.2 g Fluorine-based nonionic surfactant 0.03 g [3M, Fluorad FC-430 (trade name)] Methyl ethyl ketone 20 g Propylene glycol monomethyl ether acetate 20
g The dry coating amount of this photosensitive plate was 1.5 g / m ² . An oxygen barrier layer made of polyvinyl alcohol was provided on the photosensitive plate in the same manner as in Example 1, and exposure and development were carried out in the same manner as in Example 1 to develop the developer described in JP-B-56-42860. It was performed by immersing at 25 ° C. for 1 minute to remove the unexposed portion.

From Table 3, it can be seen that the sensitivity is higher when combined with the initiators alone.

Further, when the storage stability test in Example 1 was conducted in the same manner, it was confirmed that the same sensitivity could be obtained and the storage stability was excellent.

〔The invention's effect〕

The composition of the present invention has high sensitivity and excellent storage stability.

Claims (1)

[Claims] 1. A monomer comprising at least one ethylenically unsaturated group photopolymerizable by actinic radiation, a photopolymerization initiator, and, if necessary, a linear organic polymer. In the photopolymerizable composition, at least one of the following general formulas (I), (II) or (III) as a photopolymerization initiator (In the formula, R ₁ and R ₂ each represent an alkyl group, and R ₁ and
R ₂ may be bonded to each other to represent an alkylene group, R ₃ represents a hydrogen atom, an alkyl group or an acyl group, and X ₁ represents —OR ₅
Or The stands, R ₅ represents a hydrogen atom, an alkyl group or alkenyl group, each of R ₆ and R ₇ represents an alkyl or hydroxyalkyl group, and R ₆ and R ₇ is an alkylene group bonded to each other, oxa dialkylene Represents a group or iminodialkylene group, Y ₁ is a hydrogen atom or , Y ₂ represents a hydrogen atom, a halogen atom or a nitro group, R ₄ represents a direct bond or an alkylene group, and X ₂ represents —O.
-R ₈ -O- or R ₈ represents an alkylene group, R ₉ represents an alkyl group, and two R ₉ may be bonded to each other to represent an alkylene group. ) And at least one of the following general formula (IV) (In the formula, Ar and Ar ′ represent a substituted or unsubstituted aryl group.) A photopolymerizable composition comprising a combination of compounds represented by the formulas, and optionally an organic amine compound.