JPH10239838A - Photosensitive composition and photosensitive lithographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the photosensitive composition sufficiently developable in a short time and high in sensitivity and needing not an oxygen shielding layer and ultraviolet printing aptitude by condensing an aromatic diazonium salt with a specified compound. SOLUTION: The photosensitive composition contains the compound obtained by condensing the aromatic diazo salt and a triazine compound and/or oxadizaole compound together with a <=6C lower aliphatic aldehyde, and this diazonium salt is represented by the formula in which X is a halide of Lewis acid, an organic carboxylic or sulfonic or phosphoric acid; and each of R1 and R2 is, independently, a H atom or a hydroxyl, <=6C alkyl or such alkoxy group. The counter anion (X) of the aromatic diazonium salt is selected from alkylbenzenesulfonic acid and hexafluorophosphoric acid and tetrafluoroboric acid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a photosensitive composition and a photosensitive planographic printing plate, and more particularly to a negative photosensitive composition and a photosensitive planographic printing plate.

[0002]

2. Description of the Related Art Conventionally, as a photocurable image forming method,
After exposure of a photosensitive composition containing a diazo resin and a polymer compound having a hydroxyl group, a method of removing unexposed portions with an aqueous alkali solution has been adopted. However, the diazo resin has poor solubility in an aqueous alkaline solution, and when the solubility of the aqueous alkaline solution is deteriorated, developability of an unexposed portion is deteriorated, and there is a disadvantage that an image is not sufficiently formed.

Accordingly, Japanese Patent Application Laid-Open Nos. 2-66 and 1-245 have been disclosed.
In the technology described in JP-A-355-355 and JP-A-2-29650, the developability is improved by using a diazo resin as a cocondensation resin of diazodiphenylamine and an aromatic compound having a hydroxyl group and / or a carboxyl group, but the sensitivity is improved. However, there is a disadvantage in that it slightly deteriorates in point.

Among the negative-type image forming methods, the method considered to be the most sensitive is a photo-radical generator and a compound having at least two or more radically polymerizable ethylenically unsaturated bonds in one molecule. This method is an image forming method by photopolymerization, and since the polymerization is significantly inhibited by the presence of oxygen, a protective layer such as an oxygen barrier layer is required.

As a method of reducing polymerization inhibition by oxygen, a hybrid type photopolymerization in which photopolymerization and photocationic polymerization of an acid generator such as an onium salt and a vinyl ether compound are combined is known. The sensitivity is still lacking without an oxygen barrier.

Further, as a photosensitive composition of a photosensitive lithographic printing plate, there is a photosensitive composition obtained by condensing an aromatic diazonium salt. However, the suitability for UV printing is inferior and is not practical.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a photosensitive composition which has sufficient developability in a short time, has high sensitivity, does not require an oxygen barrier layer, and has UV printability. To provide a lithographic printing plate.

[0008]

The above objects of the present invention have been attained by the following constitutions.

(1) An aromatic diazonium salt and a triazine compound and / or an oxadiazole compound are
A photosensitive composition comprising a compound co-condensed with a lower aliphatic aldehyde having 6 or less carbon atoms.

(2) The photosensitive composition as described in (1) above, wherein the aromatic diazonium salt is represented by the following general formula (1).

[0011]

Embedded image

[0012] wherein, X represents halide Lewis acids, organic carboxylic acids, organic sulfonic acid or organic phosphoric acid, R ₁
And R ₂ each independently represent a hydrogen atom, a hydroxyl group, an alkyl group having 6 or less carbon atoms, or an alkoxy group having 6 or less carbon atoms. (3) The counter anion (X) of the aromatic diazonium salt described in the general formula (1) is an acid selected from alkylbenzenesulfonic acid, hexafluorophosphoric acid, and tetrafluoroboric acid. Or the photosensitive composition according to 2.

(4) The photosensitive composition as described in any one of (1) to (3) above, further comprising a polymer compound having a hydroxyl group.

(5) The photosensitive composition as described in (4) above, which contains at least one compound having two or more radically polymerizable ethylenically unsaturated bonds in one molecule.

(6) The photosensitive composition as described in (4) or (5) above, further comprising a cationically polymerizable vinyl ether compound.

(7) The above 1 is placed on a hydrophilic support.
7. A photosensitive lithographic printing plate comprising a photosensitive layer containing the photosensitive composition according to any one of items 1 to 6.

Hereinafter, the present invention will be described in more detail. The aromatic diazonium salt of the present invention is preferably a compound represented by the above general formula (1), and X represents a halogenated Lewis acid, organic carboxylic acid, organic sulfonic acid or organic phosphoric acid. Specific examples include methanesulfonic acid, chloroethanesulfonic acid, dodecanesulfonic acid, benzenesulfonic acid,
Toluenesulfonic acid, mesitylenesulfonic acid, and anthraquinonesulfonic acid, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, hydroxysulfonic acid, 4-acetylbenzenesulfonic acid, dimethyl-5-
Aliphatic and aromatic sulfonic acids such as sulfoisophthalate, 2,2 ', 4,4'-tetrahydroxybenzophenone, 1,2,3-trihydroxybenzophenone,
Hydroxyl-containing aromatic compounds such as 2,2 ', 4-trihydroxybenzophenone, halogenated Lewis acids such as hexafluorophosphoric acid and tetrafluoroboric acid, ClO ₄ , IO
_{4 and the} like. Particularly, an acid selected from alkylbenzenesulfonic acid, hexafluorophosphoric acid, and tetrafluoroboric acid is more preferable.

In the general formula (1), R ₁ and R ₂ each independently represent a hydrogen atom, a hydroxyl group, an alkyl group having 6 or less carbon atoms or an alkoxy group having 6 or less carbon atoms, wherein R ₁ and R ₂ are It may be the same or different, and a hydrogen atom is preferred. Hereinafter, specific examples of the compound represented by formula (1) of the present invention will be shown, but the present invention is not limited thereto.

4-diazodiphenylamine / hexafluorophosphate 4-diazodiphenylamine / tetrafluoroborate 2-methoxy-4-diazodiphenylamine / hexafluorophosphate 4-diazodiphenylamine / 2-hydroxy-4 -Methoxybenzophenone-5-sulfonate 4-diazodiphenylamine / benzenesulfonate 2-methyl-4-diazodiphenylamine / hexafluorophosphate.

The triazine compound and oxadiazole compound of the present invention are described, for example, in JP-B-57-6096, JP-B-61-51788, JP-B-1-28369, and JP-A-6-28369.
And compounds having a trihalomethyl group described in JP-A-138538, JP-A-60-177340 and JP-A-60-241049. The trihalomethyl group includes at least one directly substituted triazine nucleus or oxadiazole nucleus, and the most preferred trihalomethyl group is a trichloromethyl group.

Specific examples of the oxadiazole compound and the triazine compound of the present invention are shown below.

[0022]

Embedded image

[0023]

Embedded image

The co-condensed compound used in the photosensitive composition of the present invention can be prepared by a known method, for example, photographic science and engineering (Pho).
to, Sci. , Eng. ) Volume 17, page 33 (19
73), U.S. Pat. Nos. 2,063,631, 2,673
No. 9,498, according to the method described in each specification, the above diazonium salt and the above triazine compound and / or the above oxadiazole compound are mixed in sulfuric acid, phosphoric acid, or hydrochloric acid with a lower fatty acid having 6 or less carbon atoms. It is obtained by co-condensing with an aromatic aldehyde. Examples of the aliphatic aldehyde having 6 or less carbon atoms include paraformaldehyde, acetaldehyde, and crotonaldehyde.
Paraformaldehyde is preferred.

The content ratio of the diazonium salt and the triazine compound and / or the oxadiazole compound is such that the content of the triazine compound and / or the oxadiazole compound is 0.1 to 10 mol per mol of the diazonium salt,
Preferably it is 0.2 to 2.0 mol, more preferably 0.1 to 2.0 mol.
3 to 1.0 mol.

The high molecular compound having a hydroxyl group used in the present invention is a high molecular compound composed of repeating units derived from a (meth) acrylic acid derivative, and preferably has a weight average molecular weight (Mw) of 10,000 to 300,000. And more preferably those having a molecular weight of 50,000 to 200,000.

Monomers forming a structural unit having a phenolic hydroxyl group as the hydroxyl group include o-, m- or p-hydroxyphenyl methacrylamide, o-, m
-Or p-hydroxyphenyl methacrylate, o-,
m- or p-hydroxystyrene.

As the monomer forming the structural unit having an alcoholic hydroxyl group as the hydroxyl group, 2-hydroxyethyl methacrylate is preferred.

The high molecular compound having a hydroxyl group is a vinyl polymer, and the content of the carboxyl group-containing monomer for imparting alkali solubility is 5 mol of the total constituent monomers.
It is preferably 1% or less from the viewpoint of improving the adhesiveness and brushing property. Examples of the carboxyl group-containing monomer include (meth) acrylic acid, itaconic acid, p-carboxybenzene (meth) acrylate, and p-carboxybenzene (meth) acrylamide.

Other monomer units that can be used include, for example, ethylenically unsaturated olefins such as ethylene, propylene, isobutylene, butadiene, and isoprene, for example, styrene, α-methylstyrene, p-methylstyrene, p-chlorostyrene. Styrenes such as styrene, for example, acrylic acids such as acrylic acid and methacrylic acid, for example, unsaturated aliphatic dicarboxylic acids such as itacone, maleic acid and maleic anhydride, for example, methyl acrylate, ethyl acrylate, n-butyl acrylate Esters of α-methylene aliphatic monocarboxylic acids such as isobutyl acrylate, dodecyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α-methyl methacrylate, methyl methacrylate, ethyl methacrylate, ethyl methacrylate Kind, for example, Nitriles such as rilonitrile and methacrylonitrile, for example, amides such as acrylamide, for example, anilides such as acrylanilide, p-chloroacrylanilide, m-nitroacrylanilide, and m-methoxyacrylanilide, for example, vinyl acetate, vinyl propionate, Vinyl esters such as vinyl benzoate and vinyl acetate, for example, vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether and β-chloroethyl vinyl ether, vinyl chloride, vinylidene chloride, vinylidene cyanide, for example, 1-methyl-1-methoxy Ethylene, 1,1
-Dimethoxyethylene, 1,2-dimethoxyethylene,
1,1-dimethoxycarbonylethylene, 1-methyl-
Ethylene derivatives such as 1-nitroethylene, for example, N-
There are N-vinyl monomers such as vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidene, and N-vinyl pyrrolidone. These vinyl monomers exist in a polymer compound in a structure in which an unsaturated double bond is cleaved.

Among the above-mentioned monomers, esters and nitriles of aliphatic monocarboxylic acids exhibit excellent performance for the purpose of the present invention and are preferred. These monomers may be bonded to the polymer used in the present invention in either a block or random state. The ratio of the vinyl polymer used in the present invention in the photosensitive composition is 5 to 5.
Preferably it is 95% by weight. The vinyl polymer may be used alone or in combination of two or more. Further, it can be used in combination with another polymer compound or the like.

The compound having at least two radically polymerizable ethylenically unsaturated bonds in one molecule used in the present invention is a photopolymerizable composition containing an addition polymerizable unsaturated compound, A monomer having a double bond, or a monomer having a double bond and a polymer binder, and a typical example of such a composition is described in, for example, US Pat. No. 2,760,863. And 2,79
1,504 and the like.

For example, a composition containing methyl methacrylate, a composition containing methyl methacrylate and polymethyl methacrylate, a composition containing methyl methacrylate, polymethyl methacrylate and a polyethylene glycol methacrylate monomer, methyl methacrylate, alkyd resin And a photopolymerizable composition such as a composition containing polyethylene glycol dimethacrylate monomer.

The cationically polymerizable vinyl ether compound used in the present invention is a compound containing at least one vinyl ether group in the molecule, and is cationically reacted with an acid generated by photolysis of a cationic polymerization initiator such as an onium salt. A compound that causes polymerization or crosslinking.
Specifically, monofunctional vinyl ether compounds such as 2-chloroethyl vinyl ether, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, dodecyl vinyl ether, propenyl ether propylene carbonate, triethylene glycol divinyl ether, tripropylene glycol divinyl ether, ,
Bifunctional vinyl ether compounds such as 4-butanediol divinyl ether, 1,4-cyclohexane dimethanol divinyl ether, and divinyl ether of bisphenol A are exemplified.

The photosensitive composition of the present invention may contain a surfactant. Examples of the surfactant include an amphoteric surfactant, an anionic surfactant, a cationic surfactant, a nonionic surfactant, and a fluorine-based surfactant.

Examples of the amphoteric surfactant include lauryl dimethylamine oxide, lauryl carboxymethyl hydroxyethyl, imidazolinium betaine and the like.

As anionic surfactants, fatty acid salts,
Alkyl sulfate, alkyl benzene sulfonate, alkyl naphthalene sulfonate, alkyl sulfosuccinate, alkyl diphenyl ether disulfonate, alkyl phosphate, polyoxyethylene alkyl sulfate, polyoxyethylene alkyl allyl sulfate, naphthalene Sulfonic acid formalin condensate,
And polyoxyethylene alkyl phosphates.

Examples of the cationic surfactant include an alkylamine salt, a quaternary ammonium salt, and an alkyl betaine.

Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene derivative, oxyethylene / oxypropylene block copolymer, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, and polyoxyethylene. Examples include sorbitol fatty acid esters, glycerin fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene alkylamines, alkylalkanolamides, and the like.

Examples of the fluorine-based surfactant include a copolymer of acrylate or methacrylate containing a fluoroaliphatic group and (polyoxyalkylene) acrylate or (polyoxyalkylene) methacrylate. These compounds can be used alone or in combination of two or more. Particularly preferred is FC-430.
(Sumitomo 3M) Fluorine-based polyethylene glycol #-
2000 (Kanto Chemical). The proportion occupying in the photosensitive composition is preferably 0.01 to 10% by weight, more preferably 0.01 to 5% by weight.

A printout material for forming a visible image upon exposure can be added to the photosensitive composition. The printout material is composed of an organic dye that changes its color tone by interacting with a compound that generates an acid or a free radical upon exposure.
-36209, o-naphthoquinonediazide-4-sulfonic acid halogenide, JP-A-53-36223
-Naphthoquinonediazide-4 described in
Ester compounds or amide compounds of sulfonic acid chloride and phenols having an electron-withdrawing substituent, or aniline acid, halomethylvinyls described in JP-A-55-77742, JP-A-57-148784, etc. Oxadiazole compounds, diazonium salts and the like can be mentioned.

The photosensitive composition of the present invention may further contain a dye. The dye is used for the purpose of obtaining a visible image by exposure (exposure visible image) and a visible image after development.

As the dye, those which change color tone by reacting with free radicals or acids can be preferably used.
Here, "change in color tone" includes both a change from colorless to a color tone and a change from color to colorless or a different color tone. Preferred dyes are those that form a salt with an acid to change the color tone. For example, Victoria Pure Blue BOH (made by Hodogaya Chemical Co., Ltd.), Oil Blue #
603 (manufactured by Orient Chemical Industries), patent pure blue (manufactured by Sumitomo Mikuni Chemicals), crystal violet,
Brilliant Green, Ethyl Violet, Methyl Violet, Methyl Green, Erythrosin B, Paysic Fuchsin, Malachite Green, Oil Red, m
-Cresol purple, rhodamine B, auramine,
Triphenylmethane-based, diphenylmethane-based, oxazine-based, xanthene-based, iminonaphthoquinone-based, azomethine-based or anthraquinone-based dyes represented by 4-p-diethylaminophenyliminaphthoquinone, cyano-p-diethylaminophenylacetanilide, etc. are colored to colorless Alternatively, it is mentioned as an example of a color changing agent that changes to a different color tone.

On the other hand, examples of the color changing agent which changes from colorless to colored include leuco dyes and, for example, triphenylamine, diphenylamine, o-chloroaniline, 1,2,3-triphenylguanidine, naphthylamine, diaminodiphenylmethane, p, p '-Bis-dimethylaminodiphenylamine, 1,2-dianilinoethylene, p, p',
p "-tris-dimethylaminotriphenylmethane,
p, p'-bis-dimethylaminodiphenylmethylimine, p, p ', p "-triamino-o-methyltriphenylmethane, p, p'-bis-dimethylaminodiphenyl-4-anilinonaphthylmethane, Primary or secondary arylamine dyes represented by p ', p "-triaminotriphenylmethane are exemplified.

The proportion of the above color changing agent in the photosensitive composition is preferably from 0.01 to 10% by weight, more preferably from 0.02 to 5% by weight.

These compounds can be used alone or in combination of two or more. Particularly preferred dyes are Victoria Pure Blue BOH and Oil Blue # 603.

A sensitizing agent for improving the lipophilicity of an image area (for example, a half-esterified product of a styrene-maleic anhydride copolymer with an alcohol described in JP-A-55-527, pt-butylphenol) Novolak resins such as formaldehyde resin, or partially esterified products of these with o-quinonediazide compounds, fluorine-based surfactants, 50% fatty acid esters of p-hydroxystyrene, etc.) are preferably used. The amount of these additives varies depending on the object and purpose of use, but is generally 0.01 to 30% by weight based on the total solid content.

Each of these components is dissolved in the following solvent,
The photosensitive lithographic printing plate of the present invention can be produced by providing a photosensitive layer by coating and drying the surface of the support. There is no particular limitation on the usage of the solvent.

Solvents that can be used for dissolving the photosensitive composition used in the support produced according to the present invention include methanol, ethanol, n-propanol and i-propanol.
Aliphatic alcohols such as propanol, n-butanol, n-pentanol and hexanol, allyl alcohol, benzyl alcohol, anisole, phenetole,
n-hexane, cyclohexane, heptane, octane,
Hydrocarbons such as nonane and decane, diacetone alcohol, 3-methoxy-1-butanol, 4-methoxy-1
-Butanol, 3-ethoxy-1-butanol, 3-methoxy-3-methyl-1-butanol, 3-methoxy-
3-ethyl-1-pentanol-4-ethoxy-1-
Pentanol, 5-methoxy-1-hexanol, acetone, methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl isobutyl ketone, methyl pentyl ketone, methyl hexyl ketone, ethyl butyl ketone, dibutyl ketone, cyclopentanone, cyclohexanone, methyl cyclohexanone, γ-butyrolactone,
3-hydroxy-2-butanone, 4-hydroxy-2-
Butanone, 4-hydroxy-2-pentanone, 5-hydroxy-2-pentanone, 4-hydroxy-3-pentanone, 6-hydroxy-2-hexanone, 3-methyl-
3-hydroxy-2-pentanone, ethylene glycol, diethylene glycol, triethylene glycol,
Tetraethylene glycol, propylene glycol, ethylene glycol monoacetate, ethylene glycol diacetate, propylene glycol monoacetate,
Propylene glycol diacetate, ethylene glycol alkyl ethers and their acetates (methyl cellosolve, ethyl cellosolve, butyl cellosolve, phenyl cellosolve, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, methyl cellosolve acetate, ethyl cellosolve acetate), diethylene glycol mono Alkyl ethers and their acetates (such as diethylene glycol monomethyl ether, monoethyl ether, mono i-propyl ether, monobutyl ether, diethylene glycol monomethyl ether acetate), diethylene glycol dialkyl ethers (DMDG, DEDG, DBDG, MEDG), and triethylene glycol Ethers (monomethyl ether, monoethyl ether, dimethyl ether, diethyl ether, methyl ethyl ether, etc.), propylene glycol alkyl ethers and their acetates (monomethyl ether, monoethyl ether, n-propyl ether, monobutyl ether, dimethyl ether, diethyl ether, Monomethyl ether acetate, monoethyl ether acetate, etc.), dipropylene glycol alkyl ethers (monomethyl ether, monoethyl ether, n-propyl ether, monobutyl ether, dimethyl ether, diethyl ether), ethyl formate, propyl formate, butyl formate, amyl formate , Methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, butyric acid Carboxylic acid esters such as tyl and ethyl butyrate, dimethylformamide, dimethylsulfoxide, dioxane, tetrahydrofuran, methyl lactate, ethyl lactate, methyl benzoate, ethyl benzoate, propylene carbonate and the like, and methyl lactate and / or ethyl lactate Is preferred from the viewpoints of safety, applicability, and material solubility. These solvents can be used alone or in combination of two or more.

In the photosensitive lithographic printing plate according to the present invention, a coating layer composed of a water-insoluble organic solvent-soluble polymer compound having a film-forming ability can be formed on the photosensitive layer.

On the surface of the photosensitive layer provided as described above, a mat layer may be provided in order to shorten the evacuation time in the close contact exposure using a vacuum printing frame and to prevent printing blur. preferable. Specifically, JP-A-50-1258
No. 05, Japanese Patent Publication No. 57-6582, No. 61-28986
And a method of thermally fusing a solid powder as described in Japanese Patent Publication No. 62-33737.

For the purpose of preventing oxygen inhibition of photopolymerization, an overcoat layer made of a polymer having excellent oxygen barrier properties such as polyvinyl alcohol and acidic cellulose can be provided on the surface of the photosensitive layer.

The purpose of the matte layer is to improve the vacuum adhesion between the image film and the photosensitive lithographic printing plate in the contact exposure, thereby shortening the evacuation time, and reducing the fine halftone dots during exposure due to poor adhesion. It is to prevent. As a method for applying the mat layer, a method of thermally fusing powdered solid powder described in JP-A-55-12974, and a method of spraying polymer-containing water described in JP-A-58-182636, are used. There is a method of drying the mat layer, and any method may be used. However, it is preferable that the mat layer itself is dissolved in the alkali developer or can be removed by this.

As the coating method used for coating the photosensitive composition, the coating layer or the mat layer on the surface of the support, conventionally known methods, for example, spin coating, wire bar coating, dip coating, air knife coating, roll coating Coating, blade coating, curtain coating and the like are used.

A surface-treated support used in the present invention;
Particularly, the support subjected to the hydrophilization treatment is preferably an aluminum support, and the aluminum support includes a support made of pure aluminum and an aluminum alloy.
Various aluminum alloys can be used, for example, silicon, copper, manganese, magnesium, chromium, zinc,
An alloy of aluminum, such as a metal such as lead, bismuth, or nickel, is used.

The aluminum support is preferably subjected to a degreasing treatment to remove rolling oil on the aluminum surface prior to roughening. As the degreasing treatment, trichlene,
A degreasing treatment using a solvent such as a thinner, an emulsion degreasing treatment using an emulsion of kesilon and triethanol and the like are used. In the degreasing treatment, an aqueous solution of an alkali such as caustic soda can be used. When an aqueous solution of an alkali such as caustic soda is used for the degreasing treatment, dirt and oxide films that cannot be removed only by the above degreasing treatment can be removed.

The graining treatment method for improving the adhesion to the photosensitive layer and improving the water retention includes the following:
There are a so-called mechanical surface roughening method in which the surface is mechanically roughened, and a so-called electrochemical surface roughening method in which the surface is electrochemically roughened. Examples of the mechanical surface roughening method include methods such as ball polishing, brush polishing, blast polishing, and buff polishing. As the electrochemical surface roughening method, for example, there is a method in which a support is electrolytically treated with an alternating current or a direct current in an electrolytic solution containing hydrochloric acid or nitric acid. Any one of these
By using one or two or more methods, the support can be grained.

Since smut is formed on the surface of the support obtained by graining as described above, it is generally appropriate to appropriately perform a treatment such as washing with water or alkali etching to remove the smut. preferable. Examples of such treatment include an alkali etching method described in JP-B-48-28123 and JP-A-53-28123.
A processing method such as a sulfuric acid desmutting method described in US Pat.

The support usually has abrasion resistance, chemical resistance,
In order to improve water retention, an oxide film is formed by anodic oxidation. In this anodic oxidation, generally, a method of electrolyzing at an electric current density of 1 to 10 A / dm ² using an aqueous solution containing sulfuric acid and / or phosphoric acid at a concentration of 10 to 50% is preferably used. Patent No. 1,41
There is a method of electrolyzing at high current density in sulfuric acid described in U.S. Pat. No. 2,768, and a method of electrolyzing using phosphoric acid described in U.S. Pat. No. 3,511,661.

After the anodizing treatment, the support is subjected to a hydrophilization treatment with an alkali silicate such as an aqueous solution of sodium metasilicate, a treatment with hot water, a water-soluble polymer compound such as polyvinylphosphonic acid, or a zirconium fluoride. It is preferable to perform a surface treatment such as immersion in an aqueous potassium solution.

In using the photosensitive lithographic printing plate thus obtained, a conventionally used method can be applied. For example, a transparent original having a line image, a halftone image or the like is adhered to the photosensitive surface. The relief image is obtained by exposing and then removing the photosensitive layer in the non-image area using an appropriate developing solution. As a light source suitable for exposure, a mercury lamp, a metal halide lamp, a xenon lamp, a chemical lamp, a carbon arc lamp and the like are used.

The developing solution and the developing replenisher used for the development of the photosensitive lithographic printing plate of the present invention may contain an organic solvent, or may have a pH substantially free of an organic solvent.
It may be 12 or more alkaline aqueous solutions.

First, an aqueous alkaline developer containing substantially no organic solvent (solvent) will be described. A developer containing substantially no organic solvent means that the content of the organic solvent is 1% by weight or less.

The aqueous alkaline developer is preferably an alkaline aqueous solution containing an alkali metal silicate, and contains an alkali metal silicate such as potassium silicate, sodium silicate, sodium metasilicate, potassium metasilicate, and the like. Aqueous alkaline developers containing these alkali metal silicates contain other alkali agents such as sodium hydroxide, potassium hydroxide trisodium phosphate, dibasic sodium phosphate, sodium carbonate and potassium carbonate. Can be done. The concentration of the aqueous alkali solution at this time varies depending on the type of the photosensitive composition and the alkali, but is generally in the range of 0.1 to 10% by weight.

In the developing solution, [SiO ₂ ] / [M]
(Wherein [SiO ₂ ] represents the molar concentration of SiO ₂ ,
[M] indicates the molar concentration of the alkali metal) is 0.5 to
1.2 is preferred, and the SiO ₂ concentration is
7% by weight is preferred.

A nonionic surfactant may be added to the developing replenisher. The addition amount of the nonionic surfactant is 0.01
The range is from 10 to 10% by weight, preferably from 0.02 to 2% by weight.

The development replenisher may be composed of two or more solutions, but the supply section and the storage tank of the replenisher become complicated,
For reasons such as an increase in the size of the apparatus, it is preferable that the developing replenisher has a one-component constitution.

The pH of the developer (25 ° C.) is 12 or more and 1
3.5 or less is preferable, and the pH of the developer replenisher (25 ° C.)
Is preferably 12.5 or more and 14 or less.
It is preferable that H is higher than the pH of the developer by 0.5 or more.

The developing replenisher may contain an alkali agent other than the alkali silicate. Such alkaline agents include potassium hydroxide, sodium hydroxide, lithium hydroxide, sodium phosphate tribasic, sodium phosphate dibasic, potassium phosphate tribasic, potassium phosphate dibasic, ammonium phosphate tribasic, Inorganic alkaline agents such as dibasic ammonium phosphate, sodium metasilicate, sodium bicarbonate, sodium carbonate, potassium carbonate, ammonium carbonate, etc .; organic alkaline agents such as mono, di or triethanolamine and tetraalkyl ammonium hydroxide; And organic ammonium silicate. The content of the alkali agent in the developer is preferably in the range of 0.05 to 20% by weight, and more preferably in the range of 0.1 to 10% by weight.

In the developing replenisher, [SiO ₂ ] /
[M] (where [SiO ₂ ] represents the molar concentration of SiO ₂ and [M] represents the molar concentration of the alkali metal) is 0.2
0.8 is preferable, and the SiO ₂ concentration is 4
~ 7% by weight is preferred. Further, known additives can be added to the developing solution and the developing replenisher.

Next, a developer containing an organic solvent (solvent) will be described. The developer used in the present invention is an alkaline solution containing water as a main solvent and contains an alkali agent and an organic solvent, and if necessary, an anionic surfactant and an inorganic salt.

Examples of the alkaline agent include sodium silicate,
Potassium silicate, potassium hydroxide, sodium hydroxide,
An inorganic alkaline agent such as lithium hydroxide, sodium triphosphate, sodium bicarbonate, sodium carbonate, potassium carbonate, ammonium carbonate or an organic alkaline agent such as mono-, di- or triethanolamine or propanolamine is advantageously used. You. The content of the alkali agent in the developer is preferably 0.05 to 4% by weight,
More preferably, the range is 2 to 2% by weight.

As the organic solvent, alcohols such as n-propyl alcohol and benzyl alcohol, and glycol ethers such as phenyl cellosolve are useful. The content of the organic solvent in the developer is 0.5
-15% by weight is preferable, and the range of 1-5% by weight is more preferable.

Examples of the anionic surfactant include alkyl sulfates such as sodium lauryl sulfate; alkyl allyl sulfonates such as dodecylbenzenesulfonic acid; sodium di (2-ethylhexyl) sulfosuccinate; Sulfonates of basic fatty acid esters, for example, alkyl naphthalene sulfonates such as sodium n-butyl naphthalene sulfonate, and polyoxyethylene alkyl (phenol) ether sulfates, among which n-butyl naphthalene Alkyl naphthalene sulfonic acid salts such as sulfonic acid are preferably used. The content of the anionic surfactant in the developer is preferably 0.1 to 5% by weight, and 0.5 to 5% by weight.
A range of 1.5% by weight is more preferred.

The inorganic salts include phosphoric acid, silicic acid, carbonic acid,
A water-soluble salt of an alkali or alkaline earth such as sulfurous acid is used, and an alkali or alkaline earth sulfite is particularly preferably used. The preferred content of the inorganic salt in the developer is in the range of 0.05 to 5% by weight, more preferably in the range of 0.1 to 1% by weight.

It is also useful to further include an antifoaming agent, a wetting agent and the like in the developer, if necessary.

Next, synthesis examples of the diazo compound of the present invention and the polymer compound and the diazo compound used in the present invention will be described.

<Synthesis of polymer compound capable of forming a film> Synthesis Example 1 Synthesis of polymer compound A 5 equipped with a thermometer, a reflux condenser, a stirrer, and a nitrogen inlet pipe
A mixed solvent of 50 ml of acetone and 50 ml of methanol was placed in a 00 ml four-necked flask, and 4.43 g (0.05 mol) of 4-hydroxyphenylmethacrylamide (HyPMA) was used as a compound constituting the polymer compound.
2-hydroxyethyl methacrylamide (HEMA) 2
2.78 g (0.35 mol) of methacrylic acid (MA
A) 1.29 g (0.03 mol) of acrylonitrile (AN) 6.63 g (0.25 mol) and methyl methacrylate (MMA) 16.02 g (0.32 mol)
l) was dissolved. Furthermore, as a polymerization reaction initiator, azoisobutyronitrile 0.62 g (0.0075 mol)
Was dissolved and refluxed while stirring under a nitrogen stream. Finally, as a reaction terminator, 0.050 g of hydroquinone
Was added to terminate the reaction.

After the completion of the reaction, the reaction solution was cooled to room temperature, poured into 5 l of water for precipitation, and this was collected by filtration and dried to obtain polymer compound A.

The weight average molecular weight of the obtained polymer compound was 125,000 as measured by gel permeation chromatography (GPC) using a pullulan standard and an N, N-dimethylformamide solvent.

Synthesis Example 2 Synthesis of polymer compound B The constituent compound was prepared as follows: HyPMA 4.43 g (0.05 mol)
l), HEMA 22.78 g (0.35 mol), MA
A 1.29 g (0.03 mol), AN 6.63 g
(0.25 mol), 13.52 g of MMA (0.27 m
ol) and 3.55 g of glycidyl methacrylate
(0.05 mol), except that polymer compound B was synthesized in the same manner as polymer compound A. The molecular weight of the obtained polymer compound B was 118,000.

<Synthesis of Diazo Compound> Synthesis Example 3 Synthesis Example of Diazo Compound A: 4-diazodiphenylamine / oxadiazole compound (Compound Example 7): 75/25
(Molar ratio) of co-condensate hexafluorophosphate, Mw.
3,400 19.12 g (0.058 mol) of an oxadiazole compound (Compound Example 7) was added to 200 g of ice-cooled concentrated sulfuric acid.
-Diazodiphenylamine sulfate 50.6 g (0.17 g)
(3 mol) is stirred and dissolved while taking care that the liquid temperature does not exceed 5 ° C.

Then, 6.22 g of paraformaldehyde
(0.207 mol) is added slowly over 1 hour with stirring to carry out a condensation reaction. At this time, care is taken so that the reaction solution does not exceed 5 ° C. After completion of the paraformaldehyde addition, stirring is continued at 5 ° C. or lower for 30 minutes.

After the completion of the reaction, the reaction solution is slowly poured into 1600 ml of ethanol cooled to 0 ° C. to produce a precipitate. At this time, care is taken that the liquid temperature does not exceed 40 ° C. The precipitate is collected by suction filtration and ethanol 300 ml
The reaction intermediate 1a (diazo compound sulfate) was obtained.

The reaction intermediate 1a taken out was mixed with 240 ml of water.
And then dissolved in 90 ml of water with 19.0 parts of zinc chloride.
When 4 g (0.14 mol) are added, a precipitate is formed again. The precipitate is collected by suction filtration and the reaction intermediate 1b
(Diazo compound zinc chloride double salt) was obtained.

The reaction intermediate 1b taken out was treated with 1000 m of water.
Then, 24.8 g (0.15 mol) of ammonium hexafluorophosphate dissolved in 180 ml of water is added, and a precipitate is formed. The precipitate is collected by suction filtration,
After washing with 300 ml of ethanol, it was dried at 30 ° C. for 3 days to obtain 48.4 g of diazo compound A.

Synthesis Example 4 Synthesis Example of Diazo Compound B: 4-diazodiphenylamine / triazine compound (Compound Example 8): 75/25 (molar ratio) cocondensate hexafluorophosphate, Mw. 3,4
19.12 g of oxadiazole compound (Compound Example 7)
(0.058 mol) was changed to 22.73 g (0.058 mol) of the triazine compound (Compound Example 8).
Diazo compound B as target by carrying out in the same manner as in Synthesis Example 3
Was obtained 49.7 g. Synthesis Example 5 Synthesis Example of Diazo Compound C: 4-diazodiphenylamine / triazine compound (Compound Example 12): 75/25 (molar ratio) cocondensate hexafluorophosphate, Mw. 3,
600 19.12 g of oxadiazole compound (Compound Example 7)
(0.058 mol) with a triazine compound (Compound Example 1)
2) Other than changing to 25.05g (0.058mol)
Diazo compound C as target by carrying out in the same manner as in Synthesis Example 3
Was obtained 50.1 g.

Synthesis Example 6 Synthesis Example of Diazo Compound D: 4-diazodiphenylamine / p-hydroxybenzoic acid: 75/25 (molar ratio) cocondensate hexafluorophosphate, Mw. 19.12 g of 3,400 oxadiazole compound (Compound Example 7)
(0.058 mol) was added to p-hydroxybenzoic acid 8.0.
Except that the amount was changed to 1 g (0.058 mol), the same procedure as in Synthesis Example 3 was carried out to obtain 42.6 g of the target diazo compound D.
Obtained.

[0089]

EXAMPLES The present invention will be described more specifically with reference to the following examples.

Example 1 <Preparation of support> The surface of a 0.3 mm thick aluminum plate (material 1050, tempered H16) was degreased with 3% sodium hydroxide in a 1% hydrochloric acid bath at 25 ° C. and 80 A / dm. electrolytic etching in an electrical quantity of 400c / dm ² under the conditions of the ^second current density, washed with water, the anodized film 3 g / m ² in 30% sulfuric acid bath arranged, 85 ° C., 20 seconds, 2% sodium silicate The support of the present invention was subjected to hydrophilization treatment with an aqueous solution.

<Preparation of Photosensitive Lithographic Printing Plate Sample 1> Photosensitive solution 1 having the following composition was applied on a support prepared as described above using a wire bar so that the dry weight became 1.6 g / dm ^2. The resultant was applied and dried in an air stream at 80 ° C. for 2 minutes to prepare a photosensitive lithographic printing plate sample 1.

<Photosensitive solution 1> Polymer compound A obtained in Synthesis Example 1 8.0 g DPHA (dipentaerythritol hexaacrylate) 2.0 g Diazo compound A obtained in Synthesis Example 3 1.0 g Succinic acid 0.4 g Fluorine System surfactant (FC430, manufactured by Sumitomo 3M) 0.01 g Dye (Victoria Pure Blue BOH, manufactured by Hodogaya Chemical Co.) 0.02 g Methyl lactate 180 ml 2-ethoxypropanol 20 ml.

<Preparation of photosensitive lithographic printing plate samples 2 to 8> A photosensitive lithographic printing plate sample 2 was prepared in the same manner as the photosensitive lithographic printing plate sample 1 except that the photosensitive solution was changed to the following photosensitive solutions 2 to 8. ~
8 was created.

<Photosensitive solution 2> Diazo compound A in photosensitive solution 1
Was changed to the diazo compound B obtained in Synthesis Example 4, except that

<Photosensitive solution 3> Diazo compound A in photosensitive solution 1
Was changed to the diazo compound C obtained in Synthesis Example 5, except that

<Photosensitive solution 4> Polymer compound A in photosensitive solution 1
Is the same as the photosensitive solution 1 except that the polymer compound B obtained in the synthesis example 2 is used.

<Photosensitive solution 5> Polymer compound A 8.0 g DPHA (dipentaerythritol hexaacrylate) 1.0 g Triethylene glycol divinyl ether 1.0 g Diazo compound A 1.0 g Succinic acid 0.4 g Fluorinated surfactant (FC430, manufactured by Sumitomo 3M) 0.01 g Dye (Victoria Pure Blue BOH, manufactured by Hodogaya Chemical Co., Ltd.) 0.02 g Methyl lactate 180 ml 2-ethoxypropanol 20 ml <Photosensitive solution 6> Polymer compound A 8.0 g DPHA 2. 0 g 2,4-bis (trichloromethyl) -6- (p-methoxystyryl) -S-triazine 0.3 g succinic acid 0.4 g Fluorinated surfactant (FC430, manufactured by Sumitomo 3M) 0.01 g Dye (Victoria Pure Blue BOH, manufactured by Hodogaya Chemical Co., Ltd.) 0.02 g Methyl lactate 1 0 ml 2-ethoxypropanol 20 ml <Photosensitive solution 7> Polymer compound A 8.0 g DPHA (dipentaerythritol hexaacrylate) 1.0 g Triethylene glycol divinyl ether 1.0 g 2,4-bis (trichloromethyl) -6- ( p-methoxystyryl) -S-triazine 0.3 g diphenyliodonium hexafluorophosphate 0.3 g succinic acid 0.4 g fluorinated surfactant (FC430, manufactured by Sumitomo 3M) 0.01 g dye (Victoria Pure Blue BOH, 0.02 g Methyl lactate 180 ml 2-Ethoxypropanol 20 ml <Photosensitive solution 8> Photosensitive solution 1 was used except that diazo compound A in photosensitive solution 1 was changed to diazo compound D obtained in Synthesis Example 6. the same.

Each of the obtained photosensitive planographic printing plate samples was evaluated for sensitivity and suitability for UV printing according to the following evaluation methods. Table 1 shows the results.

(Evaluation Method) <Sensitivity Test> The obtained sample was exposed to a Konica Corporation step tablet (density difference 0.15) from a distance of 50 cm using a 2 kw metal halide lamp, and the following developer was applied. And developed with a vat (30 ° C., 30 seconds).
Further, with respect to a sample obtained by washing with water and drying, the exposure time required to form four solid layers was evaluated as sensitivity.

<UV printing suitability test> The obtained sample was adhered to a film, exposed and developed under the conditions used in the sensitivity test, and then printed on a Heidel GTO printing machine using a UV ink without causing print defects. The possible number of prints was evaluated as UV printability.

(Developer) Phenyl glycol 180.0 g Diethanolamine 85.5 g Dibutylnaphthalene sulfonate 93.0 g Pure water 3835 ml

[0102]

[Table 1]

From Table 1, it can be seen that the sample of the present invention has higher sensitivity than the sample of the comparative example and also has excellent UV printability.

[0104]

According to the present invention, it is possible to provide a photosensitive composition and a photosensitive lithographic printing plate which have high sensitivity, do not require an oxygen blocking layer, and have a suitability for UV printing.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G03F 7/038 501 G03F 7/038 501

Claims (7)

[Claims] 1. A photosensitive composition comprising a compound obtained by co-condensing an aromatic diazonium salt, a triazine compound and / or an oxadiazole compound with a lower aliphatic aldehyde having 6 or less carbon atoms. . 2. An aromatic diazonium salt represented by the following general formula (1):
The photosensitive composition according to claim 1, wherein Embedded image [In the formula, X represents a halogenated Lewis acid, an organic carboxylic acid, an organic sulfonic acid or an organic phosphoric acid, and R ₁ and R ₂ each independently represent a hydrogen atom, a hydroxyl group, an alkyl group having 6 or less carbon atoms or a carbon number. Represents 6 or less alkoxy groups. ] 3. The method according to claim 1, wherein the counter anion (X) of the aromatic diazonium salt represented by the general formula (1) is an acid selected from alkylbenzenesulfonic acid, hexafluorophosphoric acid and tetrafluoroboric acid. Item 3. The photosensitive composition according to Item 1 or 2. 4. The photosensitive composition according to claim 1, which comprises a polymer compound having a hydroxyl group. 5. The photosensitive composition according to claim 4, comprising at least one compound having two or more radically polymerizable ethylenically unsaturated bonds in one molecule. 6. The photosensitive composition according to claim 4, further comprising a cationically polymerizable vinyl ether compound. 7. The method according to claim 1, wherein the support is a hydrophilic support.
A photosensitive lithographic printing plate comprising a photosensitive layer containing the photosensitive composition according to any one of the above.