JPH08171207A - Photosensitive composition and photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE: To provide a photosensitive planographic printing plate free of printing stains, highly adhesive to a substrate and having sufficient printing durability. CONSTITUTION: This composition contains a compd. having at least one ethylenic unsaturated double bond, an acidic vinyl copolymer soluble or swollen in alkaline water, a photopolymerization initiator and a diazo resin. A diazo resin layer or a hydrophilic resin layer is provided on a substrate having a hydrophilic surface as an intermediate layer, and further a photosensitive layer contg. a photosensitive composition is furnished adjacent to the intermediate layer to constitute a photosensitive planographic printing plate. The acidic vinyl copolymer contains a structural unit having an aromatic compd. having at least one kind among the group consisting of an aromatic hydroxyl and a sulfonamide group on the side chain, a structural unit having an alcoholic hydroxyl on the side chain and a structural unit having a cyano group on the side chain.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a photosensitive composition and a photosensitive lithographic printing plate. More particularly, it relates to a negative photosensitive lithographic printing plate which can be developed with an alkali developing solution containing no organic solvent.

[0002]

2. Description of the Related Art In a negative-working photosensitive lithographic printing plate, generally, a photosensitive composition is coated on a support such as an aluminum plate, and an actinic ray such as an ultraviolet ray is irradiated through a negative image to a portion irradiated with light. Polymerize or crosslink to make it insoluble in the developer,
It can be obtained by eluting the non-irradiated portion with a developing solution and making each portion an image portion which repels water to receive ink and a non-image portion which receives water to repel ink.

Conventionally, as a photosensitive composition used for such a purpose, a combination of a diazo resin and a polymer compound has been well known in the case of a negative photosensitive lithographic printing plate, and its composition is well known. As a developing solution, one containing an organic solvent and an alkaline agent has been widely used. However, the organic solvent generally has toxicity and odor, has a risk of fire, and has many inconveniences such as being subject to BOD regulation even in the waste liquid, and the cost becomes high. Therefore, there is a need for a developer that does not contain these problems and does not contain an organic solvent, but since the polymer compound used in a conventional negative-working photosensitive lithographic printing plate is not alkali-soluble, the above-mentioned photosensitive composition is used. After exposing the photosensitive lithographic printing plate having,
When developing with an alkali developing solution containing no organic solvent, there is a problem that a residual film is generated in a portion to be removed, resulting in deterioration of printability.

On the other hand, Japanese Patent Application Laid-Open No. 61-275838 discloses a polymer compound containing a sulfonamide group and a diazo resin, and Japanese Patent Publication No. 57-43890 discloses a polymer compound containing an aromatic hydroxyl group and a diazo resin. Each of the photosensitive compositions containing is disclosed. However, when a photosensitive lithographic printing plate containing these specifically disclosed alkali-soluble components in the photosensitive layer is developed with an alkali developer containing no organic solvent, the resistance of the photosensitive layer to alkali is weak,
The problems that the image area is scratched during development and the adhesive force of the photosensitive layer to the support is lowered still remain.

Further, JP-A-59-206825, JP-A-59-53836, and JP-A-59-178449.
JP-A-57-196230 and JP-A-57-196230 disclose a technique of combining a diazo resin with a photopolymerizable composition in an attempt to obtain a photosensitive lithographic printing plate which can obtain high printing durability. In a system in which this photopolymerizable composition is combined with a diazo resin, in order to impart alkali developability to the photosensitive layer,
When a polymer compound containing a sulfonamide group or an aromatic hydroxyl group is used as a binder, the compatibility between the binder and the photopolymerizable compound is poor. However, there arises a problem that uneven development occurs during development. In addition, special fair 3-
Japanese Patent No. 65542 discloses a technique of providing a photopolymerization layer adjacent to a diazo resin intermediate layer. However, a photopolymerization layer containing the alkali-soluble binder is applied onto the intermediate layer containing the diazo resin. When the photosensitive lithographic printing plate is developed with an alkali developing solution after imagewise exposure, the adhesive force between the intermediate layer and the photopolymerizable layer is lowered, and the photopolymerizable layer is peeled off.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and when used for printing, there is no print stain, and the adhesiveness with the support is strong and sufficient printing durability can be obtained. It is intended to provide a lithographic printing plate, that is, a photosensitive lithographic printing plate in which desired development is achieved even when developed with an alkali developing solution containing no organic solvent, and in which development unevenness does not occur over time.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventor has found that by combining a polymerizable compound with a specific binder resin, the alkali developability, printing durability and storage stability are improved. It was found that an excellent photosensitive lithographic printing plate was obtained in all, and the present invention was completed.

Accordingly, the object of the present invention is to provide a compound having at least one ethylenically unsaturated double bond, an acidic vinyl copolymer soluble or swellable in alkaline water,
In a photosensitive composition containing a photopolymerization initiator and a diazo resin, the acidic vinyl copolymer has a side chain of an aromatic compound having (a) at least one member selected from the group consisting of an aromatic hydroxyl group and a sulfonamide group. A structural unit having in (b)
A photosensitive composition comprising a structural unit (c) having an alcoholic hydroxyl group as a side chain and a structural unit having a cyano group as a side chain, or a support having a hydrophilic surface A diazo resin layer or a hydrophilic resin layer containing a diazo resin as an intermediate layer, and a compound having at least one ethylenically unsaturated double bond adjacent to the intermediate layer, soluble or swellable in alkaline water In the photosensitive lithographic printing plate provided with a photosensitive layer containing the acidic vinyl copolymer and the photopolymerization initiator, the acidic vinyl copolymer is (a) a group consisting of an aromatic hydroxyl group and a sulfonamide group. Structural unit having at least one aromatic compound in the side chain (b) Structural unit having an alcoholic hydroxyl group in the side chain (c) Copolymer containing a structural unit having a cyano group in the side chain A photosensitive lithographic printing plate characterized by being, or on a support having a hydrophilic surface, a diazo resin layer or a hydrophilic resin layer containing a diazo resin is provided as an intermediate layer, and further adjacent to the intermediate layer. And a photosensitive lithographic printing plate provided with a photosensitive layer containing a compound having at least one ethylenically unsaturated double bond, an acidic vinyl copolymer soluble or swellable in alkaline water, a photopolymerization initiator and a diazo resin. In the plate, the acidic vinyl copolymer is
(A) A structural unit having an aromatic compound having at least one selected from the group consisting of an aromatic hydroxyl group and a sulfonamide group in its side chain (b) A structural unit having an alcoholic hydroxyl group in its side chain (c) a cyano group side It is easily achieved by a photosensitive lithographic printing plate characterized by being a copolymer containing structural units having a chain.

The present invention will be described in detail below. At least one ethylenically unsaturated double bond in the present invention is used.
Examples of the compound having an individual (hereinafter, abbreviated as “ethylenic compound”) include unsaturated carboxylic acids, esters of unsaturated carboxylic acids and aliphatic polyhydroxy compounds,
Obtained by esterification reaction of an unsaturated carboxylic acid and an aromatic polyhydroxy compound, an unsaturated carboxylic acid and a polyvalent carboxylic acid, and the above-mentioned aliphatic polyhydroxy compound and polyvalent hydroxy compound such as an aromatic polyhydroxy compound. Examples thereof include diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate described in JP-A-59-71048. Examples thereof include pentaerythritol triacrylate, hydroquinone di (meth) acrylate, pyrogallol triacrylate, and 2,2′-bis (4-acryloxydiethoxyphenyl) propane. Other examples include (meth) acrylamides such as ethylene bis (meth) acrylamide and hexamethylene bis (meth) acrylamide, vinyl urethane compounds and epoxy (meth) acrylates. The amount of the ethylenic compound used is usually 5 to 70% by weight, preferably 10 to 50% by weight based on the total solid content of the photosensitive composition or the photosensitive layer.

The acidic vinyl copolymer of the present invention is soluble or swellable in alkaline water and has at least one member selected from the group consisting of (a) aromatic hydroxyl group and sulfonamide group.
A structural unit having a side chain of an aromatic compound having a seed,
(B) A copolymer containing a structural unit having an alcoholic hydroxyl group in the side chain and (c) a structural unit having a cyano group in the side chain.

In the present invention, the compound containing an aromatic compound having an aromatic hydroxyl group in the side chain contained in the acidic vinyl copolymer represented by a is, for example, N- (4-
Hydroxyphenyl)-(meth) acrylamide, N-
Monomers of (meth) acrylamides such as (2-hydroxyphenyl)-(meth) acrylamide, N- (4-hydroxynaphthyl)-(meth) acrylamide: o
-, M- or p-hydroxyphenyl (meth) acrylate monomer: o-, m- or p-hydroxystyrene monomer and the like. Preferred are o-, m- or p-hydroxyphenyl (meth) acrylate monomers and N- (4-hydroxyphenyl)-(meth) acrylamide monomers, and more preferred are N- (4-
Hydroxyphenyl)-(meth) acrylamide monomer.

Specific examples of compounds having a side chain of an aromatic compound having a sulfonamide group include N- (o
-Aminosulfonylphenyl) methacrylamide, N-
(M-aminosulfonylphenyl) methacrylamide,
Methacrylamides such as N- (p-aminosulfonylphenyl) methacrylamide and acrylamides having the same substituents as described above, o-aminosulfonylphenyl methacrylate, m-aminosulfonylphenyl methacrylate, p-aminosulfonylphenyl methacrylate and the like. Examples thereof include methacrylic acid esters and acrylic acid esters having the same substituents as above. Preferred are N- (p-aminosulfonylphenyl) methacrylamide and N- (p-aminosulfonylphenyl) acrylamides.

In the present invention, specific examples of the structural unit having an alcoholic hydroxyl group in the side chain which constitutes the acidic vinyl copolymer represented by b include the following general formula as described in JP-B-52-7364. Examples of the compound shown in [I] include (meth) acrylic acid esters and acrylamides.

[0014]

Embedded image

In the formula, R ¹ is a hydrogen atom or a methyl group, and R ^{2 is}
Is a hydrogen atom, a methyl group, an ethyl group or a chloromethyl group,
And n shows the integer of 1-10. Examples of (meth) acrylic acid esters include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxypentyl (meth) acrylate, and examples of acrylamides include N. -Methylol (meth) acrylamide, N-hydroxyethyl (meth) acrylamides are mentioned. 2-hydroxyethyl (meth) acrylate is preferable.

On the other hand, the structural unit having a cyano group in the side chain constituting the acidic vinyl copolymer represented by c in the present invention includes acrylonitrile, methacrylonitrile, 2-pentenenitrile and 2-methyl-3-butene. Nitrile, 2-cyanoethyl acrylate, o-, m-,
Examples include p-cyanostyrene and the like. Preferred are acrylonitrile and methacrylonitrile.

A structural unit having an aromatic compound having a phenolic hydroxyl group and / or a sulfonamide group in its side chain, a monomer having an alcoholic hydroxyl group in its side chain, and a monomer having a cyano group in its side chain are used together with other monomers. It is also effective to polymerize and use. The monomers to be copolymerized are (1) (meth) acrylic acid, itaconic acid and its anhydrides, maleic acid and its anhydrides, monomers having a carboxyl group in the side chain such as crotonic acid, preferably methacrylic acid and acrylic acid. (2) Methyl (meth) acrylate, ethyl (meth) acrylate, methyl α-ethyl acrylate, ethyl α-ethyl acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth ) Acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, s-butyl (meth) acrylate, n-pentyl (meth) acrylate, i-pentyl (meth) acrylate, n-hexyl (meth) acrylate , T-hexyl (meth) acrylate, heptyl (meth) acryle DOO, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate.
Preferably methyl (meth) acrylate and ethyl (meth) acrylate.

(3) (meth) acrylamide, N-ethylacrylamide, N-hexylacrylamide, N-
(Meth) acrylamides such as phenylacrylamide (4) Vinyl ethers such as propyl vinyl ether, butyl vinyl ether, octyl vinyl ether and phenyl vinyl ether (5) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate and vinyl benzoate ( 6) Styrenes such as styrene, α-methylstyrene, methylstyrene and chloromethylstyrene (7) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone and phenyl vinyl ketone (8) Ethylene, propylene, isobutylene, Examples thereof include olefins such as butadiene and isoprene, N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine and the like.

The acidic vinyl copolymer used in the present invention usually has a solid content of 30 to 30 in the photosensitive composition or the photosensitive layer.
90 wt%, preferably 40 to 95 wt% may be contained. The photopolymerization initiator in the present invention is not particularly limited and conventionally known ones can be used, for example, benzoin,
Benzoin alkyl ether, benzophenone, anthraquinone, Michler's ketone, trihalomethyl-s-triazine compound, oxadiazole compound, biimidazole and Michler's ketone complex system, thioxanthone and aromatic tertiary amine complex system, etc. are preferably used. I can do things. The amount of the copolymerization initiator used in the present invention is usually 0. 0 in the solid content of the photosensitive composition or the photosensitive layer.
It is 5 to 30% by weight, more preferably 2 to 10% by weight.

As the diazo resin contained in the photopolymerizable composition and / or the intermediate layer used in the present invention, conventionally known ones can be appropriately used, but the aromatic diazonium salt and the active carbonyl-containing compound, particularly formaldehyde, can be used. The diazo resin represented by the condensate of is included, and the organic solvent-soluble diazo resin is preferable among them.

The diazo resin is, for example, a diazo resin inorganic salt which is an organic solvent-soluble reaction product of a condensate of p-diazodiphenylamine and formaldehyde or acetaldehyde, and hexafluorophosphate or tetrafluoroborate. Also, as described in U.S. Pat. No. 3,300,309, the condensate and a sulfonic acid such as paratoluenesulfonic acid or a salt thereof, a phosphinic acid such as benzenephosphinic acid or a salt thereof, a hydroxyl group-containing compound such as Examples thereof include organic solvent-soluble diazo resin organic acid salts that are reaction products of 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, or salts thereof. In the present invention, other diazo resins that can be preferably used include a carboxyl group, a sulfonic acid group, a sulfinic acid group,
It is a (co) condensate containing as a structural unit an aromatic compound having at least one organic group of an oxygen acid group and a hydroxyl group of phosphorus and a diazonium compound, preferably an aromatic diazonium compound.

The aromatic compound having at least one of the above-mentioned carboxyl group, sulfonic acid group, sulfinic acid group, phosphorus oxygen acid group, and hydroxyl group (hereinafter, these groups are referred to as “acid group”) is The molecule contains an aromatic ring substituted with at least one acid group, and in this case, two or more of the above acid groups may be substituted with the same aromatic ring. And as the above-mentioned aromatic ring, a phenyl group and a naphthyl group can be preferably cited.
The above-mentioned acid group may be directly bonded to the aromatic ring or may be bonded via a linking group. Examples of the linking group include groups having 1 or more carbon atoms containing an ether bond.

Specific examples of the aromatic compound containing at least one of the above-mentioned carboxyl group, sulfonic acid group, sulfinic acid group, phosphorus oxygen acid group and hydroxyl group include benzoic acid, o-chlorobenzoic acid, m-chlorobenzoic acid, p-chlorobenzoic acid, phthalic acid, terephthalic acid, diphenylacetic acid, phenoxyacetic acid, p-methoxyphenylacetic acid, p-methoxybenzoic acid, 2,4-dimethoxybenzoic acid, 2,4-dimethylbenzoic acid Acid, p-phenoxybenzoic acid, 4-anilinobenzoic acid, 4- (m-methoxyanilino) benzoic acid, 4- (p-methoxybenzoyl) benzoic acid, 4- (p-methylanilino) benzoic acid,
4-phenylsulfonylbenzoic acid, phenol, (o,
m, p) -cresol, xylenol, resorcin, 2
-Methylresorcin, (o, m, p) -methoxyphenol, m-ethoxyphenol, catechol, phloroglucin, p-hydroxyethylphenol, naphthol, pyrogallol, hydroquinone, p-hydroxybenzyl alcohol, 4-chlororesorcin, biphenyl 4, 4'-diol, 1,2,4-benzenetriol, bisphenol A, 2,4-dihydroxybenzophenone, 2,3,4-trihydroxybenzophenone,
p-hydroxyacetophenone, 4,4-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenylamine, 4,4'-dihydroxydiphenylsulfide cumylphenol, (o, m, p) -chlorophenol, (o, m, p) -Bromophenol, salicylic acid,
4-methylsalicylic acid, 6-methylsalicylic acid, 4-ethylsalicylic acid, 6-propylsalicylic acid, 6-laurylsalicylic acid, 6-stearylsalicylic acid, 4,6-dimethylsalicylic acid, p-hydroxybenzoic acid, 2-methyl-4-hydroxy Benzoic acid, 6-methyl-4-hydroxybenzoic acid, 2,6-dimethyl-4-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,4-dihydroxy-6-methylbenzoic acid, 2,6-dihydroxy Benzoic acid, 2,6-dihydroxy-4-benzoic acid, 4-chloro-2,6-dihydroxybenzoic acid, 4-methoxy-
2,6-dihydroxybenzoic acid, gallic acid, phloroglucincarboxylic acid, 2,4,5-trihydroxybenzoic acid, m-galloyl gallic acid, tannic acid, m-benzoyl gallic acid, m- (p-toluyl) Gallic acid, protocatechue oil-gallic acid, 4,6-dihydroxyphthalic acid, (2,4-dihydroxyphenyl) acetic acid, (2,6
-Dihydroxyphenyl) acetic acid, (3,4,5-trihydroxyphenyl) acetic acid, p-hydroxymethylbenzoic acid, p-hydroxyethylbenzoic acid, 4- (p-hydroxyphenyl) methylbenzoic acid, 4- (o- (Hydroxybenzoyl) benzoic acid, 4- (2,4-dihydroxybenzoyl) benzoic acid, 4- (p-hydroxyphenoxy) benzoic acid, 4- (p-hydroxyanilino) benzoic acid, bis (3-carboxy-4-) Hydroxyphenyl)
Amine, 4- (p-hydroxyphenylsulfonyl) benzoic acid, 4- (p-hydroxyphenylthio) benzoic acid, benzenesulfonic acid, p-toluenesulfonic acid, benzenesulfinic acid, p-toluenesulfinic acid, aniline-2- Sulfonic acid, 4-amino-m-toluenesulfonic acid, 2,5-diaminobenzenesulfonic acid, 1-naphthalenesulfonic acid, 1-amino-2-naphthalenesulfonic acid, 5-amino-2-naphthalenesulfonic acid, 7-
Amino-1,3-naphthalenedisulfonic acid, 2-amino-1,5-naphthalenedisulfonic acid, 2-sulfobenzoic acid (these sulfonic acids or sulfinic acids may be free sulfonic acids or sulfinic acids, It may be a metal salt such as sodium, potassium, lithium, cesium, calcium, barium, magnesium, aluminum, zinc, or an unsubstituted or substituted ammonium salt), phenylphosphoric acid, phenylphosphorous acid, phenylphosphonic acid, phenyl Phosphonous acid, phenylphosphinic acid, phenylphosphinic acid, benzylphosphoric acid, benzylphosphorous acid, benzylphosphonic acid, benzylphosphonous acid, benzylphosphinic acid, benzylphosphinic acid,
2-phenylethyl phosphoric acid, 2-phenylethyl phosphorous acid, 1-naphthyl phosphoric acid, 1-naphthyl phosphorous acid, 1-
Naphthylphosphonic acid, 1-naphthylphosphonous acid, 1-
Naphthylphosphinic acid, 1-naphthylphosphinic acid,
2-naphthylphosphoric acid and the like can be mentioned.

Of these, particularly preferred are 4-methoxybenzoic acid, 3-chlorobenzoic acid, 2,4-dimethoxybenzoic acid, p-phenoxybenzoic acid, 4-anilinobenzoic acid, phenoxyacetic acid, phenylacetic acid, p-acetic acid. -Hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, benzenesulfonic acid, p-toluenesulfinic acid, 1-naphthalenesulfonic acid, phenylphosphoric acid, phenylphosphonic acid. Examples of the aromatic diazonium compound forming the constitutional unit of the above-mentioned copolymerized diazo resin include, for example, JP-B-49-4800.
Although diazonium salts such as those listed in JP-A-1 can be used, diphenylamine-4-diazonium salts are particularly preferable.

The diphenylamine-4-diazonium salts are derived from 4-amino-diphenylamines, and such 4-amino-diphenylamines include 4-amino-diphenylamine and 4-amino-3-.
Methoxy-diphenylamine, 4-amino-2-methoxy-diphenylamine, 4'-amino-2-methoxy-
Diphenylamine, 4'-amino-4-methoxy-diphenylamine, 4-amino-3-methyldiphenylamine, 4-amino-3-ethoxy-diphenylamine, 4
-Amino-3-β-hydroxyethoxydiphenylamine, 4-amino-diphenylamine-2-sulfonic acid,
4-amino-diphenylamine-2-carboxylic acid, 4-
Amino-diphenylamine-2'-carboxylic acid and the like can be mentioned, and particularly preferred are 3-methoxy-4-amino-diphenylamine and 4-amino-diphenylamine.

The co-condensed diazo resin can be obtained by a known method, for example, Photographic Science and Engineering (Photo. Sci. Eng.) No. 17
Vol. 33 (1973), U.S. Pat. No. 2,063,6.
No. 31, 2,697,498, the method described in each of the specification, aromatic compounds and aldehydes having a diazonium salt, carboxy and or hydroxyl acid group in sulfuric acid, phosphoric acid or hydrochloric acid, such as paraformaldehyde, It can be obtained by polycondensing acetaldehyde, benzaldehyde or ketones such as acetone and acetophenone. The charged molar ratio of the aromatic compound having at least one of the acid groups and the aromatic diazo compound is 1: 0.1 to 0.1: 1, preferably 1 :.
0.5-0.2: 1, more preferably 1: 1-0.2:
It is 1. Further, in this case, the total amount of the aromatic compound and the aromatic diazo compound having at least one of the acid groups and the aldehyde or the ketone are usually in a molar ratio of 1: 0.6.
To 1.2, preferably 1: 0.7 to 1.5, and reacted at a low temperature for a short time, for example, for about 3 hours to obtain a co-condensed diazo resin.

The counter anion of the diazo resin used in the present invention includes an anion that forms a salt with the diazo resin in a stable manner and makes the resin soluble in an organic solvent. These include organic carboxylic acids such as decanoic acid and benzoic acid, organic phosphoric acids such as phenylphosphoric acid and sulfonic acids, and typical examples are methanesulfonic acid, chloroethanesulfonic acid, dodecanesulfonic acid, benzenesulfonic acid. ,
Toluenesulfonic acid, naphthalenesulfonic acid, dibutylnaphthalenesulfonic acid, mesitylenesulfonic acid, and anthraquinonesulfonic acid, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, hydroxysulfonic acid, 4-acetylbenzenesulfonic acid, dimethyl-
Aliphatic and aromatic sulfonic acids such as 5-sulfoisophthalate, 2,2 ', 4,4'-tetrahydroxybenzophenone, 1,2,3-trihydroxybenzophenone, 2,2', 4-trihydroxybenzophenone Hydroxyl group-containing aromatic compound, hexafluorophosphoric acid, halogenated Lewis acid such as tetrafluoroboric acid, CIO ₄ ,
Examples thereof include perhalogenic acid such as IO _4, etc., but are not limited thereto. Among these, particularly preferred are dibutylnaphthalene sulfonic acid, hexafluorophosphoric acid, 2-hydroxy-4-methoxybenzophenone-
It is 5-sulfonic acid.

The molecular weight of the above co-condensed diazo resin can be obtained as an arbitrary value by variously changing the molar ratio of each monomer and the condensation conditions, but it is effectively used for the intended purpose of the present invention. To have a molecular weight of about 400-1
Those of 10,000, preferably about 800 to 5,000 are suitable.

The thickness of the intermediate layer provided as necessary in the present invention can be arbitrarily changed, but it must be a thickness capable of performing a uniform bond forming reaction with the upper photosensitive layer when exposed. . Usually about 1 to 500m as a dry solid
Good application rate of g / m ² , 100-400 mg / m ²
Is particularly good. Furthermore, in addition to diazo resins, diazo stabilizers, sensitizers, antihalation agents, polymer binders,
Various additives such as surfactants can also be blended. The ratio of the diazo resin to the intermediate layer is 5 to 100% by weight,
Preferably, it is 20 to 100% by weight. The intermediate layer is formed by dissolving the diazo resin used in the present invention and any compound in a solvent, coating the solution on a support, and drying. In addition, as a method other than coating, the support can be obtained by immersing the support in a solution containing a component for an intermediate layer and drying.

A dye may be further used in the photosensitive composition of the present invention. The dye is used for the purpose of obtaining a visible image by exposure (exposed visible image) and / or a visible image after development. As the dye, those that change color tone by reacting with free radicals or acids can be preferably used. Here, "the color tone changes" includes any change from colorless to colored color tone, and from colored to colorless or different colored color tone. Preferred dyes are those which form a salt with an acid to change the color tone.

For example, Victoria Pure Blue BOH
[Hodogaya Chemical Co., Ltd.], Oil Blue # 603 [Orient Chemical Co., Ltd.], Patent Pure Blue [Sumitomo Mikuni Chemical Co., Ltd.], Crystal Violet, Brilliant Green, Ethyl Violet, Methyl Violet, Methyl Green, Erythrosin B, Basic Fuchsin, malachite green, oil red, m-cresol purple, rhodamine B, auramine, 4-p-diethylaminophenyliminonaphthoquinone, cyano-p-diethylaminophenylacetanilide, and other triphenylmethanes, diphenylmethanes, oxazines,
Examples of the discoloring agent include xanthene-based, iminonaphthoquinone-based, azomethine-based, or anthraquinone-based dyes that change from a colored color to a colorless or different colored 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, p, Examples thereof include primary or secondary arylamine dyes represented by p ′, p ″ -triaminotriphenylmethane.

Particularly preferably, triphenylmethane type and diphenylmethane type dyes are effectively used, more preferably triphenylmethane type dyes, and particularly Victoria Pure Blue BOH. The above-mentioned dye is usually contained in the solid content of the photosensitive composition in an amount of 0.5 to 10% by weight, preferably about 1 to 5% by weight.

Various additives can be further added to the photosensitive composition of the present invention. For example, alkyl ethers (eg, ethyl cellulose,
Methyl cellulose), fluorine-based surfactants, nonionic surfactants [for example, Pluronic L-64 (manufactured by Asahi Denka Co., Ltd.)], a plasticizer for imparting flexibility and abrasion resistance to the coating film ( For example, butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate, trioctyl phosphate, tetrahydrofurfuryl oleate, acrylic acid or methacrylic acid Oligomers and polymers), an oil sensitizer for improving the oil sensitivity of the image area (for example, a half-esterified product of an alcohol of a styrene-maleic anhydride copolymer described in JP-A-55-527) with alcohol, stability Agents [eg phosphoric acid, phosphorous acid, organic acids (citric acid, oxalic acid Benzenesulfonic acid, naphthalenesulfonic acid, 4-methoxy-2-hydroxy-5-sulfonic acid, tartaric acid)], development accelerators (such as higher alcohols, acid anhydrides and the like) and the like. The amount of these additives added varies depending on the intended purpose, but generally, with respect to the total solid content of the photosensitive composition,
It is 0.01 to 30% by weight.

When such a photosensitive composition is applied to the production of a photosensitive lithographic printing plate, it is coated on a suitable support. The support used for the above-mentioned photosensitive lithographic printing plate includes paper, plastic (for example, polyethylene, polypropylene, polystyrene, etc.) laminated paper, metal plate such as aluminum (including aluminum alloy), zinc, copper, etc. , Cellulose diacetate, cellulose triacetate,
Films of plastics such as cellulose propionate, polyethylene terephthalate, polyethylene, polypropylene, polycarbonate polyvinyl acetal, etc., papers or plastic films laminated or vapor-deposited with the metals described above, steel plates plated with aluminum or chrome, etc. Of these, aluminum and aluminum-coated composite supports are particularly preferable.

Further, it is desirable that the surface of the aluminum material is roughened for the purpose of enhancing water retention and improving adhesion to the photosensitive layer. Examples of the roughening method include generally known brush polishing method, ball polishing method, electrolytic etching, chemical etching, liquid honing, sand blasting and the like and combinations thereof, preferably brush polishing method, electrolytic etching, chemical method. Etching and liquid honing, of which the roughening method involving the use of electrolytic etching is particularly preferred. Further, as an electrolytic bath used in electrolytic etching,
An aqueous solution containing an acid, an alkali or a salt thereof or an aqueous solution containing an organic solvent is used, and among these, an electrolytic solution containing hydrochloric acid, nitric acid or a salt thereof is particularly preferable.
Further, the surface-roughened aluminum plate is desmutted with an acid or alkali aqueous solution, if necessary. The aluminum plate thus obtained is preferably subjected to anodizing treatment, and particularly preferably, a method of treating with a bath containing sulfuric acid or phosphoric acid can be mentioned. Also,
Further, if necessary, surface treatment such as treatment with an alkali silicate or hot water, or immersion in a water-soluble polymer compound or an aqueous solution of potassium fluorozirconate can be performed.

In order to provide the above-mentioned photosensitive composition on a support, a photosensitive diazo resin, a lipophilic polymer compound and, if necessary, various additives in predetermined amounts are added in an appropriate solvent (methyl cellosolve, ethyl). Cellosolve, methyl cellosolve acetate, acetone, methyl ethyl ketone, methanol,
It may be dissolved in dimethylformamide, dimethylsulfoxide, water or a mixture thereof to prepare a coating solution of the photosensitive composition, which is coated on a support and dried. The concentration of the photosensitive composition at the time of coating is preferably in the range of 1 to 50 weight. In this case, the coating amount of the photosensitive composition may be about 0.2 to 10 g / m ² .

The layer of the photosensitive composition provided on the support has an excellent oxygen barrier property such as polyvinyl alcohol and acidic celluloses in order to prevent the polymerization inhibiting action by oxygen in the air. You may provide the protective layer which consists of a polymer. The photosensitive material coated on the support is
Conventional conventional methods are applied. That is, by exposing through a transparent original image having a line image, a halftone image, etc., and then developing with an aqueous developer, a negative relief image is obtained with respect to the original image. Examples of the active light source suitable for exposure include a carbon arc lamp, a mercury lamp, a xenon lamp, a metal halide lamp, and a strobe.

The developer for the photosensitive composition of the present invention is not particularly limited, but an alkaline aqueous solution containing substantially no organic solvent is particularly preferable. The term "substantially free from" of an organic solvent means that the organic solvent is not contained to the extent that the effects on hygiene, safety, etc. are impaired, and generally 1% by weight or less in the developer composition. No problem.

The content of the organic solvent is preferably 0.5% by weight or less, and more preferably, no organic solvent is contained. As the alkaline agent used in the developing solution, preferably potassium silicate,
Lithium silicate, sodium silicate, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium phosphate tribasic, sodium phosphate dibasic, potassium phosphate tribasic,
Dibasic potassium phosphate, sodium carbonate, potassium carbonate and the like can be mentioned. Among these, a developer containing an alkali silicate such as potassium silicate, lithium silicate, or sodium silicate is the most preferable because it has good development gradation, and the composition of the alkali silicate is [SiO ₂ ] / [M] =
0.5 to 1.5 (here, [SiO ₂ ] and [M] represent the molar concentration of SiO _{2 and} the molar concentration of total alkali metal, respectively), and 0.8 to 8% by weight of SiO ₂ The developer contained is preferably used. Of this alkaline silicate composition, a molar ratio of [SiO ₂ ] / [M] = 0.5
A developing solution having a concentration of .about.0.75 and SiO ₂ of 0.8 to 4% by weight is preferably used because the developing waste solution can be easily neutralized due to its low concentration, while 0.75 to 1.3 A developing solution having a molar ratio of 1 to 8% by weight and having a SiO ₂ content of 1 to 8% by weight has a high buffering power and a high processing capacity, and is therefore preferably used.
The pH (25 ° C.) of the developer according to the present invention is 12 or more, preferably 12.5 to 14. In the developer, for example, sodium sulfite, potassium sulfite,
Water-soluble sulfites such as lithium sulfite and magnesium sulfite can be added. The preferred content of sulfite in the developer composition is 0.05 to 4% by weight, more preferably 0.1 to 1% by weight.

Further, in the developing solution, there is disclosed in JP-A-50-5132.
4, anionic surfactants and amphoteric surfactants, as described in JP-A No. 4-75255, and nonionic surfactants as described in JP-A-59-75255 and 60-111246. By containing at least one of the agents, or by containing a polymer electrolyte as described in JP-A-55-95946 and JP-A-56-142528, the wettability to the photosensitive composition is improved. Is preferably used because it can enhance the gradation and the gradation. The amount of such a surfactant added is not particularly limited, but is preferably 0.003 to 3% by weight, and particularly preferably 0.
A concentration of 006 to 1% by weight is preferred. Further, it is preferable that 20 mol% or more of potassium is contained as the alkali metal of the alkali silicate in all alkali metals, because the generation of insoluble matter in the developer is small, and potassium is more preferably 90%.
It is to be contained in an amount of not less than mol%, and most preferably 100% by mol of potassium. Further, the developer used in the present invention may contain an antifoaming agent. Suitable defoamers include organosilane compounds.

[0042]

EXAMPLES The present invention will now be specifically described with reference to examples, but the present invention is not limited to these examples. Synthesis of co-condensed diazo resin 3.5 g (0.025 mol) of p-hydroxybenzoic acid,
And p-diazodiphenylamine sulfate 21.75 g
(0.075 mol) was dissolved in 90 g of concentrated sulfuric acid under ice cooling. After this reaction 2.7 g paraformaldehyde (0.09 mol) was added slowly. At this time, the reaction temperature was controlled not to exceed 10 ° C. Then, stirring was continued for 2 hours under ice cooling. The reaction mixture was poured into 1 l of methanol under ice cooling, and the formed precipitate was filtered. After washing with ethanol, the precipitate was dissolved in 200 ml of pure water, and a cold concentrated aqueous solution containing 10.5 g of zinc chloride was added to the solution. The generated precipitate was filtered, washed with ethanol, and dissolved in 300 ml of pure water. 1 in this liquid
A cold concentrated aqueous solution of 3.7 g ammonium hexafluorophosphate was added. The resulting precipitate was filtered off, washed with water and dried at 30 ° C. for 24 hours to obtain diazo resin 1. When the molecular weight of this co-condensed diazo resin 1 was measured by GPC (gel permeation chromatography), the weight average molecular weight was about 2300.

Example 1 An aluminum plate was degreased with 3% sodium hydroxide and this was degreased in a 11.5 g / l hydrochloric acid bath at 25 ° C. and 80 A / dm ^2.
Electrolytic etching was performed at a current density of 11 seconds for 11 seconds, followed by washing with water and anodic oxidation for 15 seconds in a 30% sulfuric acid bath at 30 ° C. and 11.5 A / dm ² . Next, 1% sodium metasilicate aqueous solution 8
It was treated at 5 ° C. for 30 seconds, washed with water and dried to obtain an aluminum plate for a lithographic printing plate. Next, the following photosensitive solution I was prepared.

[0044]

[Table 1]

After the photosensitive solution I was filtered, it was coated on a support using a bar coater so that the weight after drying was 1.5 g / m ² . The photosensitive lithographic printing plate thus obtained was designated as Sample A. The copolymer of the photosensitive solution I is changed to poly (N
-(4-Aminosulfonylphenyl) methacrylamide / acrylonitrile / methyl methacrylate / 2-hydroxyphenyl methacrylate / methacrylic acid) copolymer Copolymer with a molar ratio of 20/30/25/20/5 (M
w: 45000) was also prepared, and a photosensitive solution II was prepared and coated on the same support by the same method to obtain sample B.

As a comparative example, the copolymer of the photosensitive solution I was changed to a copolymer of poly (N- (4-hydroxyphenyl) methacrylamide / acrylonitrile / methylmethacrylate / methacrylic acid) in a molar ratio of 20/30/45/5 (Mw). : 40000), and prepare a photosensitive solution III
Sample C was obtained by the same method. The obtained photosensitive lithographic printing plate was stored at room temperature for 10 days, and then the negative transparent original image was brought into vacuum contact with it, and then it was exposed to 60 cm with a 2 kW metal halide lamp.
Exposure from the distance of 30 seconds, developing solution of the following composition, 25 ℃
After immersing in 40 seconds for 40 seconds, it was lightly rubbed with absorbent cotton and developed.

[0047]

[Table 2] Developer A Potassium silicate: 225 g Potassium hydroxide: 25 g Pure water: 1000 g

After development, when uneven development on the plate was examined,
Samples A and B were uniformly developed and no development unevenness was observed. On the other hand, on Sample C, band-like unevenness with a film-like image area was observed.

Example-2 An undercoating liquid having the following composition was prepared and coated on the surface of the support of Example-1 using a bar coater so that the coating amount after drying was about 0.2 g / m ² .

[0050]

[Table 3] Undercoating liquid Co-condensation diazo resin 1 g Methyl cellosolve 100 g

A photosensitive lithographic printing plate obtained by applying the photosensitive solution I on this undercoat layer was designated as sample D. On the same undercoat layer, a photosensitive solution IV obtained by removing the cocondensed diazo resin from the photosensitive solution-I was applied, and the obtained photosensitive lithographic printing plate was designated as sample E. As a comparative example, Photosensitive Solution III of Example-1 was applied onto the same undercoat layer, and the resulting photosensitive lithographic printing plate was used as Sample F. As a comparative example, the photosensitive solution V excluding the photosensitive solution-III co-condensed diazo resin of Example-1 was applied onto the same undercoat layer, and the obtained photosensitive lithographic printing plate was used as sample G. The obtained photosensitive lithographic printing plate was stored at room temperature for 10 days, and then the negative transparent original image was vacuum-contacted thereto,
3 from a distance of 60 cm with a 2 kW metal halide lamp
It was exposed for 0 seconds, immersed in a developer having the following composition at 25 ° C. for 40 seconds, and then lightly rubbed with absorbent cotton to develop.

[0052]

[Table 4] Developer A Potassium silicate: 225 g Potassium hydroxide: 25 g Pure water: 1000 g

Adhesive images were obtained in D, E and F, whereas images were peeled off during development in G. Further, when the development unevenness on the plate was examined, Samples D and E were uniformly developed and no development unevenness was observed, whereas on Sample F, band-like unevenness where the image areas were partially film-like was observed. I was seen. The lithographic printing plate thus obtained (Sample D,
E, F) was used to print on high-quality paper with a commercially available ink (Toyo High Plus M Red) with a diamond printing machine manufactured by Mitsubishi Heavy Industries. Samples D and E were obtained even with 60,000 copies. The printed matter had no problem and an excellent printed matter was obtained, whereas the sample F could print only 20,000 copies.

[0054]

INDUSTRIAL APPLICABILITY The photosensitive composition and the photosensitive lithographic printing plate of the present invention are photosensitive materials which, when used for printing, have no printing stain and have a strong adhesion to a support and sufficient printing durability. Type lithographic printing plate, that is, even when developed with an alkali developing solution containing no organic solvent, desired development is achieved, and uneven development with time does not occur.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomoyuki Matsumura 1 Sakura-cho, Hino-shi, Tokyo Konica stock company (72) Inventor Nobuyuki Ishii 1 Sakura-cho, Hino-shi, Tokyo Konica stock company (72) Inventor Noriyuki Kizu No. 1 Sakura-cho, Hino City, Tokyo Konica Stock Company

Claims (7)

[Claims] 1. A photosensitive composition comprising a compound having at least one ethylenically unsaturated double bond, an acidic vinyl copolymer soluble or swellable in alkaline water, a photopolymerization initiator and a diazo resin, A structural unit in which the acidic vinyl copolymer has (a) an aromatic compound having at least one member selected from the group consisting of an aromatic hydroxyl group and a sulfonamide group in its side chain, and (b) a structure unit having an alcoholic hydroxyl group in its side chain. A photosensitive composition comprising a unit (c) a copolymer containing a structural unit having a cyano group in a side chain. 2. The acidic vinyl copolymer contains 5 to 40 mol% of a structural unit a, 5 to 40 mol% of a structural unit b, and 10 to 40 mol% of a structural unit c. Photosensitive composition. 3. The photosensitive composition according to claim 1, wherein the structural unit b of the acidic vinyl copolymer is 2-hydroxyethyl methacrylate. 4. A diazo resin layer or a hydrophilic resin layer containing a diazo resin is provided as an intermediate layer on a support having a hydrophilic surface, and an ethylenically unsaturated double bond is further provided adjacent to the intermediate layer. In a photosensitive lithographic printing plate provided with a photosensitive layer containing at least one compound, an acidic vinyl copolymer soluble or swellable in alkaline water, and a photopolymerization initiator, the acidic vinyl copolymer is (a) ) At least one selected from the group consisting of aromatic hydroxyl groups and sulfonamide groups
Structural unit (b) having an aromatic compound containing a seed in its side chain
A photosensitive lithographic printing plate comprising a structural unit (c) having an alcoholic hydroxyl group as a side chain and a copolymer containing a structural unit having a cyano group as a side chain. 5. A diazo resin layer or a hydrophilic resin layer containing a diazo resin is provided as an intermediate layer on a support having a hydrophilic surface, and an ethylenically unsaturated double bond is further provided adjacent to the intermediate layer. In a photosensitive lithographic printing plate provided with a photosensitive layer containing a compound having at least one, an alkaline water-soluble or swellable acidic vinyl copolymer, a photopolymerization initiator and a diazo resin, the acidic vinyl copolymer is (A)
A structural unit having an aromatic compound having at least one selected from the group consisting of an aromatic hydroxyl group and a sulfonamide group in its side chain (b) a structural unit having an alcoholic hydroxyl group in its side chain (c) having a cyano group in its side chain A photosensitive lithographic printing plate characterized by being a copolymer containing structural units. 6. The acidic vinyl copolymer contains 5 to 40 mol% of a structural unit a, 5 to 40 mol% of a structural unit b, and 10 to 40 mol% of a structural unit c. The photosensitive lithographic printing plate described. 7. The photosensitive lithographic printing plate according to claim 4, wherein the structural unit b of the acidic vinyl copolymer is 2-hydroxyethyl methacrylate.