JPH05323596A - Photosensitive composition and photosensitive lithographic printing plate - Google Patents

Abstract

PURPOSE:To improve the developing property in an alkaline developing solution by including diazo resin having at least one specific repeating unit in the photosensitive layer. CONSTITUTION:A photosensitive composition includes diazo resin having at least one repeating unit as expressed by the formula. In the formula, R<1> denotes a hydrogen atom, alkyl group, alkoxyl group, hydroxyl group, carboxyester group, or carboxyl group that may have a substituent, and R<2> denotes a hydroxyl group or a group having at least one alcoholic or phenolic hydroxyl group, and R<3>, R<4> denote a hydrogen atom, alkyl group, or alkoxyl group respectively, and X denotes -NH-, -O-, or -S-, and Y<-> denotes an anion. As the R<2>, that which includes an OH group is preferable. By providing an OH group in the base material of diazo resin, the hydrophilic property of the resin can be enhanced, and the developing property can be improved.

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. In particular, it relates to a photosensitive composition containing a diazo resin and a photosensitive lithographic printing plate having a layer containing a diazo resin.

[0002]

2. Description of the Related Art Conventionally, a diazo resin used in a photosensitive composition or a photosensitive lithographic printing plate has a p-type composition.
It is a polycondensation resin of diazodiphenylamine and formaldehyde. However, a photosensitive lithographic printing plate comprising a conventional photosensitive composition containing such a diazo resin, and a layer containing such a diazo resin, in terms of printing durability and developability,
It was not always satisfactory. In particular, an alkaline developer containing substantially no organic solvent is preferable from the standpoint of pollution or health of workers, but it has a problem that developability is insufficient when such a developer is used. It was

[0003]

It is an object of the present invention to solve the above problems and to provide a photosensitive lithographic printing plate having excellent printing durability, good developability, and substantially good developability with an alkaline developer containing substantially no organic solvent. It is an object to provide a plate, and also to provide a photosensitive composition that can be used for a printing plate having such an effect.

[0004]

The invention according to claim 1 of the present invention is characterized by containing a diazo resin having at least one repeating unit represented by the following general formula (I). And a composition that achieves the above object.

The invention of claim 2 of the present invention provides a photosensitive lithographic printing plate having a photosensitive layer on a support having a hydrophilic surface, wherein the repeating unit represented by the following general formula (I) is contained in the photosensitive layer. A photosensitive lithographic printing plate characterized by containing a diazo resin having at least one of the above-mentioned.

According to the invention of claim 3 of the present invention, a polymerizable compound having an ethylenically unsaturated bond, a photopolymerization initiator, and an alkali-soluble or swellable film can be formed on a support having a hydrophilic surface. A photosensitive layer formed of a photopolymerizable substance composed of a high molecular weight polymer or a photosensitive lithographic printing plate having such a photosensitive layer and an intermediate layer, wherein the intermediate layer or the photosensitive layer is represented by the following general formula (I). A photosensitive lithographic printing plate comprising a diazo resin having at least one repeating unit described above, which achieves the above object.

A fourth aspect of the present invention is directed to a photosensitive layer having an alkali-soluble or swelling photocrosslinkable polymer or a photosensitive lithographic plate having such a photosensitive layer and an intermediate layer on a support having a hydrophilic surface. A photosensitive lithographic printing plate, comprising a diazo resin having at least one repeating unit represented by the following general formula (I) in the intermediate layer or the photosensitive layer in the printing plate. The above object is achieved.

[Chemical 5]

In the formula, R ¹ represents a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a hydroxy group, a carboxyester group or a carboxyl group, and R ²
Represents a hydroxy group or a group having at least one alcoholic or phenolic hydroxy group, and R ³
Represents a hydrogen atom, an alkyl group or an alkoxy group, and R
⁴ represents a hydrogen atom, an alkyl group or an alkoxy group,
X is -NH -, - O-, or -S- are shown, Y ^- represents an anion.

In the present invention, the following groups are particularly preferable as R ² in the general formula (I).

[Chemical 6]

Although the function of the present invention is not always clear, by adding an OH group to the skeleton of the diazo resin, the hydrophilicity of the resin is enhanced, the developability is improved, and the association force between the molecules and the support. It is considered that the adhesion property with and the printing durability are improved.

The present invention will be described in more detail below. First, the diazo resin used in the present invention will be described.
The diazo resin used in the present invention has at least one repeating unit represented by the above-mentioned general formula (I) (hereinafter, such a diazo resin may be referred to as "the diazo resin of the present invention").

As means for synthesizing the diazo resin of the present invention, polycondensation of diphenylamine-4-diazonium salts and a carbonyl compound having a hydroxyl group can be mentioned.

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-methoxydiphenylamine, 4-amino-3-methyldiphenylamine, 4-amino-3-ethoxy-diphenylamine, 4
-Amino-3-β-hydroxy-ethoxydiphenylamine, 4-amino-diphenylamine-2-sulfonic acid, 4-amino-diphenylamine-2-carboxylic acid,
4-amino-diphenylamine-2'-carboxylic acid and the like can be mentioned. Particularly preferably 3-methoxy-4
-Amino-diphenylamine and 4-amino-diphenylamine.

As the carbonyl compound having a hydroxyl group, formic acid, p-hydroxybenzaldehyde, m
-Hydroxybenzaldehyde, o-hydroxybenzaldehyde, hydroxyacetaldehyde, hydroxypropanal, hydroxybutanal, hydroxypentanal, hydroxyhexanal, hydroxyheptanal and the like can be mentioned. Particularly preferred are formic acid and p-hydroxybenzaldehyde.

The diazo resin of the present invention can be prepared 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.
According to the method described in each of No. 31, No. 2,679,498, it can be obtained by polycondensing a diazonium salt and a carbonyl compound having a hydroxyl group in sulfuric acid, phosphoric acid or hydrochloric acid.

At this time, in the polycondensation of the diazonium salt and the aldehyde, both are usually in a molar ratio of 1:
0.6-1: 2, preferably 1: 0.7-1: 1.5
Then, the high-sensitivity diazo resin is obtained by reacting at low temperature for a short time, for example, at 10 ° C. or less for about 3 hours.

The counter anion of the diazo resin includes an anion which forms a salt with the diazo resin in a stable manner and makes the resin soluble in an organic solvent. Examples of such anions include organic carboxylic acids such as decanoic acid and benzoic acid and benzoic acid, organic phosphoric acids such as phenylphosphoric acid and sulfonic acid, and typical examples include methanesulfonic acid, Chloroethanesulfonic acid, dodecanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, mesitylenesulfonic acid, and anthraquinonesulfonic acid, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid,
Aliphatic and aromatic sulfonic acids such as hydroxysulfonic acid, 4-acetylbenzenesulfonic acid and dimethyl-5-sulfoisophthalate, 2,2 ', 4,4'-tetrahydroxybenzophenone, 1,2,3-trihydroxy benzophenone, 2,2 ', 4-hydroxyl group-containing aromatic compound of trihydroxy benzophenone, hexafluorophosphate, halide Lewis acids such as tetrafluoroboric acid, the like ClO _4, perhalogenic acid IO ₄ such like You can However, it is not limited to this. Among these, particularly preferable are hexafluorophosphoric acid and tetrafluoroboric acid.

The above-mentioned co-condensed diazo resin can be obtained with an arbitrary molecular weight by varying the molar ratio of each monomer and the condensation conditions. In the present invention, it is generally preferred that the molecular weight is about 400 to 10,000.
Those of about 800 to 5,000 are suitable, and those of about 800 to 5,000 are more suitable.

The diazo resin of the present invention may be one in which an aromatic compound having at least one of at least one of a carboxyl group and a hydroxyl group is introduced into the main chain by cocondensation.

Such an aromatic compound having a carboxyl group and / or a hydroxy group has an aromatic ring substituted with at least one carboxyl group and / or an aromatic ring substituted with at least one hydroxyl group in the molecule. In this case, the carboxyl group and the hydroxyl group may be substituted with the same aromatic ring or may be substituted with another aromatic ring. This carboxyl group or hydroxyl group may be directly bonded to the aromatic ring, or may be bonded via a bonding group. Preferred examples of the above-mentioned aromatic group include an aryl group such as a phenyl group and a naphthyl group.

In the co-condensed diazo resin that can be used in the present invention, the number of carboxyl groups bonded to one aromatic ring is preferably 1 or 2, and the number of hydroxyl groups bonded to one aromatic ring is 1 to 3 is preferable. When the carboxyl group or the hydroxyl group is bonded to the aromatic ring via the bonding group, examples of the bonding group include an alkylene group having 1 to 4 carbon atoms.

Specific examples of the aromatic compound having a carboxyl group and / or a hydroxyl group as the constitutional unit of the co-condensed diazo resin include benzoic acid, o-chlorobenzoic acid, m-chlorobenzoic acid and p-chloro. Benzoic acid, phthalic acid, terephthalic acid, diphenylacetic acid, phenoxyacetic acid, p-methoxyphenylacetic acid, p-methoxybenzoic acid, 2,4-dimethoxybenzoic acid, 2,4-dimethylbenzoic acid, p-phenoxybenzoic acid, 4 -Anilinobenzoic acid, 4- (m-methoxyanilino) benzoic acid, 4- (p
-Methylbenzoyl) 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, phloroglysin, 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'-dihydroxydiphenyl sulfide, 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-hydroxybenzoic acid, 6
-Methyl-4-hydroxybenzoic acid, 2,6-dimethyl-4-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,4-dihydroxy-6-methylbenzoic acid,
2,6-dihydroxybenzoic acid, 2,6-dihydroxy-4-benzoic acid, 4-chloro-2,6-dihydroxybenzoic acid, 4-methoxy-2,6-dioxybenzoic acid, gallic acid, phloroglucin carvone Acid, 2,4,5-trihydroxybenzoic acid, m-galloyl gallic acid, tannic acid, m-benzoyl gallic acid, m- (p-toluyl) gallic acid, protocatechuyl gallic acid, 4,6-dihydroxy Phthalic 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-hydroxyphenyl) Examples thereof include sulfonyl) benzoic acid and 4- (p-hydroxyphenylthio) benzoic acid. Of these, particularly preferable are salicylic acid, p-hydroxybenzoic acid, p-methoxybenzoic acid, and metachlorobenzoic acid.

The content of these diazo resins is preferably 3 to 30 wt% in the layer of the photosensitive composition or the photosensitive lithographic printing plate (photosensitive layer, etc.). More preferably, it is 5 to 20 wt%.

The synthesis examples of diazo resins 1 to 4 will be described below.

Synthesis of diazo resin 1 14.5 g of p-diazodifernylamine sulfate was dissolved in 40 g of concentrated sulfuric acid under ice cooling. To this reaction solution
61 g of formic acid was added slowly. At this time, the reaction temperature was added so as not to exceed 10 ° C. Then, stirring was continued under ice cooling for 2 hours. The reaction mixture was cooled with ice,
The mixture was added dropwise to 500 ml of ethanol, and the formed precipitate was filtered off. After washing the precipitate with ethanol, the precipitate was dissolved in 100 ml of pure water, and the solution was added to 6.
An aqueous solution in which 8 g of zinc chloride was dissolved was added. The resulting precipitate was filtered off, washed with ethanol and dissolved in 150 ml of pure water. An aqueous solution in which 8 g of ammonium hexafluorophosphate was dissolved was added to this solution, the resulting precipitate was filtered off, washed with water and ethanol, and then dried at 25 ° C. for 3 days to obtain diazo resin 1.

Synthesis of diazo resin 2 In the above synthesis of diazo resin 1, diazo resin 2 was obtained in the same manner except that 4.27 g of p-hydroxybenzaldehyde was used instead of 1.61 g of formic acid.

Synthesis of diazo resin 3 21.75 g of p-diazodifernylamine sulfate and 3.5 g of p-hydroxybenzoic acid were dissolved in 90 g of concentrated sulfuric acid under ice cooling. To this reaction solution was slowly added 4.14 g of formic acid. At this time, the reaction temperature was added so as not to exceed 10 ° C. Then, stirring was continued under ice cooling for 2 hours. The reaction mixture was added dropwise to 1 liter of ethanol under ice cooling, and the generated precipitate was filtered off. After washing the precipitate with ethanol, the precipitate was dissolved in 200 ml of pure water, and an aqueous solution in which 10.5 g of zinc chloride was dissolved was added to this solution. The resulting precipitate was filtered off, washed with ethanol and dissolved in 300 ml of pure water. An aqueous solution in which 29 g of sodium dodecylbenzenesulfonate was dissolved was added to this solution, and the resulting precipitate was filtered off, washed with water and ethanol, and then dried at 25 ° C. for 3 days to obtain diazo resin 2.

Synthesis of diazo resin 4 In the synthesis of diazo resin 3, p-hydroxybenzoic acid was changed to 4.5 g of N- (4-hydroxyphenyl) methacrylamide and sodium dodecylbenzenesulfonate was further added to ammonium hexafluorophosphate. 0.7 g
After that, the same procedure was followed to obtain a diazo resin 4.

At the same time, for comparison, a synthetic example of a conventionally used diazo resin will be described.

Synthesis of diazo resin 5 In the synthesis of diazo resin 1, the same procedure was followed except that formic acid was changed to 1.61 g of paraformaldehyde.
Got

The polymerizable compound having an ethylenically unsaturated bond which forms the photosensitive layer on the support in the invention of claim 3 has, for example, a boiling point of 100 ° C. or higher at room temperature and at least one molecule. A monomer or oligomer having a molecular weight of 10,000 or less and having one addition-polymerizable unsaturated group can be used.

Specific examples of such monomers as oligomers include monofunctional acrylates and methacrylates such as polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate and phenoxyethyl (meth) acrylate; polyethylene glycol di (Meth) acrylate, polypropylene di (meth) acrylate, trimethylolethane tri (meth) acrylate, neopentyl glycol di (meth)
Acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, hexanediol di (meth) acrylate, tri (acryloyloxyethyl) isocyanurate, glycerin, trimethylolethane, etc. (Meth) acrylate after adding ethylene oxide or propylene oxide to the polyhydric alcohol described in JP-B-48-4
1708, Japanese Examined Patent Publication No. 50-6034, JP-A-51-3
7193, urethane acrylates as described in each specification, JP-A-48-64183 and JP-B-49.
Examples thereof include polyfunctional acrylates and methacrylates such as polyester acrylates described in JP-B-43191 and JP-B-52-30490, and epoxy acrylates obtained by reacting an epoxy resin with a (meth) acrylic acid. Furthermore, in detail, the Japan Adhesive Association Vo
l. 20, No. The polymerizable compounds introduced as photocurable monomers and oligomers on pages 7,300 to 308 can also be used.

Further, it is preferable to use a photopolymerization initiator together with the compound having a polymerizable unsaturated bond in the molecule. As the photopolymerization initiator that can be contained in the photosensitive layer of the photosensitive lithographic printing plate of the present invention, known photopolymerization initiators can be optionally used, but preferred examples are thioxanthone-based, anthraquinone-based, and benzophenone-based. , Benzoin type, benzoic acid type and the like. Specifically, they are the following compounds.

[Chemical 7]

[Chemical 8]

[Chemical 9]

As the polymerization initiator, a trihalomethyloxathiazole compound or an s-triazine trihalomethyl compound can also be preferably used.
Examples of the photopolymerization initiator include the following compounds.

[Chemical 10]

In the invention of claim 3, the photopolymerization initiator is contained in an amount of 0.1 to 20 in the entire photosensitive composition forming the photosensitive layer.
%, Particularly preferably 0.5 to 10%.

Next, in the invention of claim 4, the alkali-soluble or swellable photocrosslinkable polymer which can be used by being contained in the photosensitive layer on the support will be described.

As such a compound, a polymer compound having a substituent capable of being crosslinked by a cycloaddition reaction can be used.

Preferred are polymer compounds having a maleimide group in the side chain, cinnamyl group having a photodimerizable unsaturated double bond adjacent to an aromatic ring, cinnamylidene group, chalcone group, etc. in the side chain or main chain. And the polymer compound described in 1.

These polymer compounds are obtained by polymerizing a monomer having one or more polymerizable unsaturated bonds and one or more photocrosslinking groups in a suitable solvent using a known polymerization initiator. Be done. At this time, it may be copolymerized with another arbitrary monomer, if necessary. Examples of the low molecular weight compound having one or more polymerizable unsaturated bonds and one or more photocrosslinking groups include, for example, Japanese Patent Publication No. 49-28122.
JP-B-55-12042, JP-A-50-24384
No. 5, Japanese Patent Publication No. 51-37673, and Japanese Patent Laid-Open No. 62-2843.
50, JP-A-51-125474, JP-A-52-9
88, etc. are mentioned.

Among these low molecular weight compounds, those particularly preferably used in the present invention are compounds represented by the following general formula (A) or (B).

[Chemical 11]

In the formula, R ⁴ and R ⁸ are each H or CH.
Indicates ₃ .

R ⁵ and R ⁹ are C, H, N, O and S, respectively.
Of these, a divalent linking group consisting of two or more atoms is shown. R
⁶ and R ⁷ each represent H, a halogen atom or an alkyl group, and R ⁶ and R ⁷ may be taken together to form a 5- or 6-membered ring. In addition, as the alkyl group of R ⁶ and R ⁷ ,
Those having 1 to 4 carbon atoms are preferable, and a methyl group is particularly preferable. Further, as the halogen atom, Cl, B
r and I are preferred.

R ¹⁰ , R ¹¹ are H, CN, NO ₂ ,
Halogen and an alkyl group having 1 to 6 carbon atoms are shown.

X ² and X ³ are each a single bond or --C.
OO -, - CONH- indicates, X ⁴ represents a O or NH.

Ar represents an aromatic group which may have a substituent or a heteroaromatic group, and preferably a phenyl group which may have a substituent.

Examples of the low molecular weight compound represented by the general formula (A) include the compounds shown below.

[Chemical formula 12]

In the formula, R ⁴ , R ⁶ and R ⁷ have the same meanings as described above, and n 1 to n 9 are integers, preferably 1 to 1
It is 2. R ¹² represents H or CH ₃ .

Examples of the low molecular weight compound represented by the general formula (B) include the compounds shown below.

[Chemical 13]

In the formula, R ⁸ , R ¹⁰ , R ¹¹ and Ar have the same meanings as described above, and n10 to n18 are integers, preferably 1
To 12. R ¹³ represents H or CH ₃ .

Further, it may be a multicomponent copolymer with one or more kinds of polymerizable low molecular weight compounds other than these.

Examples of such polymerizable low molecular weight compounds include acrylic acid, methacrylic acid, acrylonitrile, methacrylonitrile, acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers. , Vinyl esters, styrenes, crotonic acid esters and the like.

As the solvent used when synthesizing such a polymer compound, for example, ethylene dichloride, cyclohexanone, methyl ethyl ketone, acetone, methanol, ethanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-
Methoxyethyl acetate, 1-methoxy-2-propanol, 1-methoxy-2-propyl acetate, N,
Examples thereof include N-dimethylformamide, N, N-dimethylacetamide, toluene, ethyl acetate, methyl lactate, ethyl lactate, and dimethyl sulfoxide.

These solvents may be used alone or in admixture of two or more.

The above-mentioned polymer compound has an average of two or more photocrosslinkable groups in the side chain per molecule and preferably has a weight average molecular weight of 1,000 or more, more preferably 2,000 to 30. It is in the range of 10,000.

The number average molecular weight is preferably 800 or more, more preferably 1000 to 250,000. The polydispersity (weight average molecular weight / number average molecular weight) is preferably 1 or more, more preferably 1.1 to 10.

Further, the above-mentioned polymer compound may contain unreacted low-molecular compound. In this case, the ratio of the low molecular weight compound to the high molecular weight compound is preferably 15% by weight or less.

These polymer compounds preferably contain a copolymerization component having a photocrosslinkable group in a molar ratio of 20% or more, more preferably 30% to 90%.

The polymer compound used in the present invention is
Either a random polymer or a block polymer obtained by copolymerizing the above monomers may be used, but a random polymer is preferably used.

The content of the polymer compound is 10 to 99% by weight, preferably 50 to 95% by weight, based on the photosensitive composition forming the photosensitive layer.

If necessary, the photosensitive composition forming the photosensitive layer may contain a photosensitizer.

As the photosensitizer, a triplet sensitizer having a maximum absorption that allows practically sufficient light absorption in a range of 300 nm or more is preferable.

Examples of the sensitizer include benzophenone derivatives, benzanthrone derivatives, quinones, aromatic nitro compounds, naphthothiazoline derivatives, benzothiazoline derivatives, thioxanthones, naphthothiazole derivatives, ketocoumarin compounds, benzothiazole derivatives, naphthofuranone compounds, pyrylium salts. , Thiapyrylium salt and the like. Specifically, Michler's ketone, N, N '
-Diethylaminobenzophenone, benzanthrone,
(3-methyl-1,3-diaza-1,9-benz) anthrone picramide, 5-nitroacenaphthene, 2-chlorothioxanthone, 2-isopropylthioxanthone,
Dimethylthioxanthone, Methylthioxanthone-1-
Ethyl carboxylate, 2-nitrofluorene, 2-
Dibenzoylmethylene-3-methylnaphthothiazoline,
Examples thereof include 3,3-carbonyl-bis (7-diethylaminocoumarin), 2,4,6-triphenylthiapyrylium perchlorate and 2- (P-chlorobenzoyl) naphthothiazole. An appropriate amount of these sensitizers added is about 1 to about 20% by weight, more preferably 3 to 10% by weight, based on the total composition.

Next, the photosensitive composition of the present invention or the photosensitive layer of the photosensitive lithographic printing plate of the present invention may contain other polymer compounds as a binder resin. As such a polymer compound, an alkali-soluble / swellable polymer compound can be used. Here, the alkali-soluble / swellable polymer compound is either alkali-soluble or alkali-swellable, or has both properties. One kind or two or more kinds of such polymer compounds can be optionally used.

The alkali-soluble polymer compound is an alkaline solution, for example, having a pH of 12.0 at 25 ° C.
Among the above alkaline solutions, those that elute into the solution can be preferably used. Further, as the alkali-swelling polymer compound, those which are easily peeled from the support when the volume is expanded by permeation of the liquid in an alkaline solution and formed by coating on the support are preferable. Can be used.

In order to specify the molecular weights of various polymer compounds used in the practice of the present invention, the value of the molecular weight measured by GPC using a polystyrene standard can be used.

That is, the weight average molecular weight is measured by GPC
(Gel permeation chromatography method), and the number average molecular weight MN and the weight average molecular weight MW can be calculated by Morio Tsuge, Tatsuya Miyabayashi, and Masayuki Tanaka, "Chemical Society of Japan," pages 800-805 (1972). According to the method described in (1), the peaks in the oligomer region can be leveled (the peaks and valleys of the peaks can be connected to each other).

When the alkali-soluble / swellable polymer compound is used in the present invention, the following compounds can be used, for example. That is, as the polymer compound that can be used, polyamide, polyether, polyester, polycarbonate, polystyrene, polyurethane, polyvinyl chloride and copolymers thereof, polyvinyl butyral resin, polyvinyl formal resin, shellac, epoxy resin, phenol resin, acrylic resin, etc. Is mentioned.

Preferred are copolymers of the monomers shown in the following (1) to (12), which are alkali-soluble and swellable polymer compounds.

(1) A monomer having an aromatic hydroxyl group, for example, N- (4-hydroxyphenyl) acrylamide or N- (4-hydroxyphenyl) methacrylamide, o-, m-, p-hydroxystyrene, o-, m.
-, P-hydroxyphenyl-acrylate or -methacrylate.

(2) Monomers having an aliphatic hydroxyl group, such as 2-hydroxyethyl acrylate or 2,2-
Hydroxyethyl methacrylate.

(3) α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid and maleic anhydride.

(4) Methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate,
(Substituted) alkyl acrylates such as 2-chloroethyl acrylate, 2-hydroxyethyl acrylate, glycidyl acrylate, N-dimethylaminoethyl acrylate.

(5) Methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, cyclohexyl methacrylate, 2-hydroxyethyl methacrylate, 4-
(Substituted) alkyl methacrylates such as hydroxybutyl methacrylate, glycidyl methacrylate and N-dimethylaminoethyl methacrylate.

(6) Acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N-ethylacrylamide, N-hexylacrylamide, N-cyclohexylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, N- Acrylamide or methacrylamide such as nitrophenylamide and N-ethyl-N-phenylacrylamide.

(7) Ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, butyl vinyl ether,
Vinyl ethers such as octyl vinyl ether and phenyl vinyl ether.

(8) Vinyl acetates such as vinyl acetate, vinyl chloroacetate, vinyl butyrate and vinyl benzoate.

(9) Styrenes such as styrene, α-methylstyrene, methylstyrene and chloromethylstyrene.

(10) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone and phenyl vinyl ketone.

(11) Olefins such as ethylene, propylene, isobutylene, butadiene and isoprene.

(12) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, acrylonitrile, methacrylonitrile and the like.

Further, a monomer copolymerizable with the above-mentioned monomer may be copolymerized. In addition, a copolymer pair obtained by copolymerizing the above-mentioned monomers is also modified, for example, with glycidyl methacrylate, glycidyl acrylate, etc., but is not limited thereto.

More specifically, a hydroxyl group-containing copolymer containing the monomers listed in (1) and (2) above is preferable, and an aromatic hydroxyl group-containing copolymer is more preferable.

If necessary, polyvinyl butyral resin, polyurethane resin, polyamide resin, epoxy resin, novolac resin, natural resin or the like may be added to the above copolymer.

In the present invention, the photosensitive layer is soluble in alkali.
When a copolymer that is a swelling polymer compound is used, the following copolymers are particularly preferable.

That is, 1 to 50 mol% of (a) a structural unit having an alcoholic hydroxyl group and / or a structural unit having a phenolic hydroxyl group in the molecular structure, (b) the following general formula (VI):

[Chemical 14]

(Wherein R ²¹ represents a hydrogen atom or an alkyl group), the structural unit represented by 5 to 40 mol%,
(C) The following general formula (VII)

[Chemical 15]

(Wherein R ²² represents a hydrogen atom, a methyl group or an ethyl group, and R ²³ represents an alkyl group having 2 to 12 carbon atoms or an alkyl-substituted aryl group). Polymer compounds containing ˜60 mol% are preferred. And its weight average molecular weight is 20,
Copolymers of 000 to 200,000 are more preferred.

Specific examples of the monomer forming the structural unit having an alcoholic hydroxyl group of the above (a) include the following general formula (VII) as described in JP-B-52-7364.
Examples of the compound shown in I) include (meth) acrylic acid esters and acrylamides.

[Chemical 16]

In the formula, R ²⁴ is a hydrogen atom or a methyl group, R ^24
25 represents a hydrogen atom, a methyl group, an ethyl group or a chloromethyl group, and n represents an integer of 1 to 10.

Examples of (meth) acrylic acid esters include 2-hydroxyethyl (meth) acrylate and 2-hydroxyethyl (meth) acrylate.
Hydroxypropyl (meth) acrylate, 2-vidroxypentyl (meth) acrylate and the like, and examples of acrylamides include N-methylol (meth) acrylamide and N-hydroxyethyl (meth) acrylamide. 2-hydroxyethyl (meth) acrylate is preferable.

Examples of the monomer (a) for forming the structural unit having a phenolic hydroxyl group include N- (4-hydroxyphenyl)-(meth) acrylamide and N- (2-hydroxyphenyl)-( Monomers of (meth) acrylamides such as (meth) acrylamide, N- (4-hydroxynaphthyl)-(meth) acrylamide; o-, m- or p-hydroxyphenyl (meth) acrylate monomers; o-, m- or p -Hydroxystyrene monomer and the like. Preferably,
o-, m- or p-hydroxyphenyl (meth) acrylate monomer, N- (4-hydroxyphenyl)-
It is a (meth) acrylamide monomer, more preferably N- (4-hydroxyphenyl)-(meth) acrylamide monomer.

The structural unit having an alcoholic hydroxyl group and / or the structural unit having a phenolic hydroxyl group is
It is preferably selected from the range of 1 to 50 mol%, more preferably 5 to 30 mol% in the polymer compound.

The monomer having a cyano group in the side chain forming the structural unit represented by the general formula (VI) is
Examples thereof include acrylonitrile, methacrylonitrile, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, o-, m-, p-cyanostyrene and the like. Preferred are acrylonitrile and methacrylonitrile. The proportion of the structural unit having a cyano group in the side chain contained in the molecule of the polymer compound is preferably 5 to 40 mol%, more preferably 15 to 35 mol%.
Selected from the range of.

Examples of the monomer having a carboxy ester group in the side chain forming the structural unit represented by the general formula (VII) include ethyl acrylate, ethyl methacrylate, propyl acrylate, butyl acrylate, amyl acrylate and amyl methacrylate. Hexyl acrylate, octyl acrylate, 2-chloroethyl acrylate, 2-hydroxyethyl acrylate,
Examples thereof include glycidyl acrylate. The unit formed from the monomer is preferably 25 in the polymer compound.
-60 mol%, more preferably 35-60 mol%.

The above-mentioned preferred polymer compound may contain, for example, 2 to 30 mol% of a structural unit having a carboxyl group in its molecular structure.

As the monomer forming the structural unit having a carboxyl group, methacrylic acid, acrylic acid,
Examples thereof include maleic anhydride and maleic acid. The monomer is 2 to 30 mol% in the polymer compound, preferably
It is selected from the range of 5 to 15 mol%.

The above structural units are not limited to the units formed from the monomers given as specific examples.

When an alkali-soluble / swellable polymer compound is used in the present invention, it is preferably usually 40 to 99% by weight, more preferably 50 to 95% by weight in the solid content of the photosensitive composition constituting the photosensitive layer. % Contained. Further, in the present invention, when a photosensitive diazo resin is used, it is also preferably 1 to 60% by weight, more preferably 3 to 30% by weight.
It is contained by weight%.

The photosensitive layer of the photosensitive lithographic printing plate of the present invention can contain an acid and / or an acid anhydride.

When an acid is used, it can be arbitrarily selected from organic acids and inorganic acids. As the organic acid, at least one carboxyl group of monocarboxylic acid or polycarboxylic acid is used.
Acids having a unit are preferred. Malic acid, tartaric acid, and polyacrylic acid (commercially available under the trade name Jurimer) can be preferably used. Further, organic acids (citric acid, oxalic acid, benzenesulfonic acid, naphthalenesulfonic acid, 4-methoxy-2-hydroxybenzophenone-5-sulfonic acid, etc.) can also be used. As the inorganic acid, phosphoric acid, phosphorous acid and the like can be used. These acids can also function as stabilizers.

When an acid anhydride is used, the type of acid anhydride is also arbitrary, and those derived from aliphatic / aromatic monocarboxylic acids such as acetic anhydride, propionic anhydride, benzoic anhydride, and succinic anhydride. , Maleic anhydride, glutaric anhydride, phthalic anhydride, and the like derived from aliphatic / aromatic dicarboxylic acids.

The photosensitive lithographic printing plate of the present invention may contain a dye, particularly a dye which changes from colored to colorless or discolors by treatment. Preferably, a dye that changes from colored to colorless is included. The dye contained in the photosensitive lithographic printing plate may be contained in the photosensitive layer to form a colored photosensitive layer, or may be contained by providing a colored layer different from the photosensitive layer.

The following can be mentioned as dyes that can be preferably used in the practice of the present invention.

That is, for example, Victoria Pure Blue B
OH (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,
Triphenyl typified by methyl green, erythrosine B, basic fuchsin, malachite green, oil red, m-cresol purple, rhodamine B, auramine, 4-p-dimethylaminophenyliminonaphthoquine, cyano-p-diethylaminophenylacetanilide and the like. Methane-based, diphenylmethane-based, oxazine-based, xanthene-based, iminonaphthoquinone-based, azomethine-based or anthraquinone-based dyes can be mentioned as examples of dyes that change color from colorless to a different color.

Particularly preferred are triphenylmethane-based and diphenylmethane-based dyes, more preferred are triphenylmethane-based dyes, and Victoria Pure Blue BOH is particularly preferred.

When the above-mentioned color changing agent is contained in the photosensitive layer,
Usually, it is preferably contained in an amount of about 0.5 to about 10% by weight, more preferably about 1 to 5% by weight.

In the present invention, various additives can be further added to the photosensitive layer.

Examples of the additives include alkyl ethers (eg ethyl cellulose, etc.) for improving the coating property.
Methyl cellulose), fluorosurfactants, nonionic surfactants [for example, BLURONIC L-64 (manufactured by Asahi Denka Co., Ltd.)], a plasticizer for imparting flexibility and abrasion resistance of 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, oligomers of acrylic acid or methacrylic acid and Polymer), an oil-sensitizing agent 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). You can The amount of these additives added varies depending on the intended use and purpose, but is generally preferably 0.01 to 30% by weight based on the total solid content.

To obtain the photosensitive lithographic printing plate of the present invention, a predetermined amount of the diazo resin of the present invention and, if necessary, an alkali-soluble / swellable polymer compound and various additives are appropriately used. It is dissolved in a solvent (methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, acetone, methyl ethyl ketone, methanol, dimethylformamide, dimethylsulfoxide, water or a mixture thereof) to adjust the coating solution of the photosensitive composition, and this is used as a support. It can be coated on the above and dried to obtain a printing plate. The concentration of the photosensitive composition at the time of coating is preferably in the range of 1 to 50% by weight. In this case, the coating amount of the photosensitive composition is preferably about 0.2 to 10 g / m ² .

In the practice of the present invention, the photosensitive lithographic printing plate may have a colored photosensitive layer made of a photosensitive composition containing a dye, and a colored layer made of a dye or other binder and the photosensitive composition. It may have a structure having two layers including a photosensitive layer composed of. In the case of having the two layers, either layer may be arranged on the support side.

In the photosensitive lithographic printing plate of the present invention, various supports can be used. An aluminum plate is particularly preferable. However, when the aluminum plate is used without treatment, there are problems that the adhesiveness of the photosensitive composition is poor and the photosensitive composition is decomposed. In order to eliminate this problem, various proposals have hitherto been made.

For example, a method in which the surface of an aluminum plate is grained and then treated with silicate (US Pat. No. 2,71,71).
4,066), a method of treating with an organic acid salt (US Pat. No. 2,714,066), a method of treating with phosphonic acid and derivatives thereof (US Pat. No. 3,220,832).
, A method of treating with potassium hexafluorozirconate (US Pat. No. 2,946,683), a method of anodizing and a method of treating with an aqueous solution of an alkali metal silicate after anodizing (US Pat. No. 3,181, No. 461) etc.

In a preferred embodiment of the invention,
Aluminum plate (including alumina laminate, the same applies below)
After degreasing the surface, brush polishing method, ball polishing method,
Graining is performed by a chemical polishing method, an electrolytic etching method, or the like, and preferably, an electrolytic etching method that can obtain a deep and uniform grain is performed. The anodizing treatment is carried out by using, for example, an inorganic salt such as phosphoric acid, chromic acid, boric acid, sulfuric acid or the like, or an organic acid such as oxalic acid alone, or an aqueous solution in which two or more kinds of these acids are mixed, preferably an aqueous sulfuric acid solution It is performed by passing an electric current through an aluminum plate as an anode. Anodic oxide coating weight is preferably 5-60 mg / dm ^2, more preferably from 5 to 30 mg / dm ^2.

In carrying out the sealing treatment in the practice of the present invention, the treatment is preferably carried out by immersing in a sodium silicate aqueous solution having a concentration of 0.1 to 3% at a temperature of 80 to 95 ° C. for 10 seconds to 2 minutes. .. More preferably, it is then immersed in water at 40 to 95 ° C. for 10 seconds to 2 minutes for treatment.

The photosensitive lithographic printing plate of the present invention can be exposed to light and developed by a conventional method. That is, for example,
Sensitize through a transparent original image with line image, halftone image, etc.
Then, by developing with an aqueous developer, a negative leaf image can be obtained with respect to the original image. Suitable light sources for exposure include carbon arc lamps, mercury lamps, xenon lamps, metal halide lamps, strobes and the like.

Imagewise exposed photosensitive lithographic printing plate (PS
The method for developing the plate) is arbitrary and, for example, various conventionally known methods can be used.

Specifically, a method of immersing the image-exposed PS plate in a developing solution, a method of ejecting the developing solution from a large number of nozzles onto the photosensitive layer of the PS plate, and a PS solution with a sponge moistened with the developing solution are used. Various methods such as a method of wiping the photosensitive layer of the plate and a method of roller-coating the surface of the photosensitive layer of the PS plate with a developing solution can be used. Further, after the developing solution is applied to the photosensitive layer of the PS plate in this manner, the surface of the photosensitive layer can be lightly rubbed with a brush or the like.

The developing solution for developing the photosensitive lithographic printing plate of the present invention is arbitrary as long as it can develop the developing solution.

Preferably, a developer containing a specific organic solvent, an alkaline agent and water as essential components can be used. Here, the specific organic solvent means a solvent capable of dissolving or swelling the non-exposed area (non-image area) of the photosensitive layer when contained in a developing solution, and moreover, with respect to water at room temperature (20 ° C.). Organic solvents having a solubility of 10% by weight or less are preferable. As such an organic solvent,
It only needs to have the above characteristics,
Although not limited only to the following, for example, ethyl acetate, propyl acetate,
Carboxylic esters such as butyl acetate, amyl acetate, benzyl acetate, ethylene glycol monobutyl acetate, butyl acetate and butyl levulinate; ketones such as ethyl butyl ketone, methyl isobutyl ketone and cyclohexanone; ethylene glycol monobutyl ether,
Alcohols such as ethylene glycol benzyl ether, ethylene glycol monophenyl ether, benzyl alcohol, methylphenyl carbinol, n-amyl alcohol, methyl amyl alcohol; alkyl-substituted aromatic hydrocarbons such as xylene; methylene dichloride, ethylene dichloride, There are halogenated hydrocarbons such as monochlorobenzene. These organic solvents may be used alone or in combination of two or more. Among these organic solvents, ethylene glycol monophenyl ether and benzyl alcohol are particularly effective. Also,
The content of these organic solvents in the developer is preferably about 1 to 20% by weight, and particularly 2 to 10% by weight.
In this case, more favorable results are obtained.

On the other hand, preferred alkaline agents contained in the developing solution include (A) sodium silicate, potassium silicate, potassium hydroxide, sodium hydroxide, lithium hydroxide, sodium di- or triphosphate or Inorganic alkali agents such as ammonium salts, sodium metasilicate, sodium carbonate or ammonium, (B) mono-, di- or trimethylamine, mono-, di- or triethylamine, mono- or diisopropylamine, n-butylamine, mono-, di- or triethanolamine, mono , Organic amine compounds such as di- or triisopropanolamine, ethyleneimine and ethylenediamine.

The content of these alkaline agents in the developing solution is usually preferably 0.05 to 4% by weight, more preferably 0.5 to 2% by weight.

Further, in order to further improve the storage stability, printing durability and the like, it is preferable to include a water-soluble sulfite in the developer. As such a water-soluble sulfite, an alkali or alkaline earth metal salt of sulfite is preferable, and examples thereof include sodium sulfite, potassium sulfite, lithium sulfite and magnesium sulfite. The content of these sulfites in the developer composition is usually preferably 0.05 to 4% by weight, more preferably 0.1 to 1% by weight.

When such a developing solution is brought into contact with the photosensitive lithographic printing plate after development exposure or is ablated with the developing solution, it is generally at room temperature to 40 ° C. for 10 to 60 seconds, and then the exposed portion of the photosensitive layer is exposed. The photosensitive layer in the non-exposed area is completely removed without adversely affecting the above.

The developing conditions can be appropriately selected according to the developing method. As an example, in the developing method by immersion, for example, a developing solution at about 10 to 40 ° C. is used to form about 10 to 80
A method of dipping for a second can be used.

[0125]

EXAMPLES Examples of the present invention will be described below. As a matter of course, the present invention is not limited to the following examples.

Examples 1 to 7 and Comparative Examples 1 and 2 (Preparation of Support) Support 1 A 0.24 mm thick aluminum plate (material 1050, temper H16) was heated at 65 ° C. in a 5 wt% caustic soda aqueous solution. 1
After degreasing for 5 minutes, wash with water, and in a 0.5M hydrochloric acid aqueous solution at 25 ° C and a current density of 60 A / dm ² ,
Electrolytic etching treatment was performed for 0 seconds. Then, after desmutting at 60 ° C. for 10 seconds in a 5 wt% caustic soda aqueous solution, the temperature is set to 20 ° C. in a 20 wt% sulfuric acid aqueous solution.
Anodization treatment was performed for 1 minute under the condition of current density of 3 A / dm ² . Further, the substrate was washed with water, sealed with a 2.5% aqueous solution of sodium silicate at 80 ° C. for 20 seconds, and washed with water to prepare a support 1.

Support 2 In the same manner as in the preparation of Support 1, a desmutted aluminum plate was placed in a 20 wt% phosphoric acid aqueous solution at a temperature of 20 ° C. and a current density of 3 A / dm ² for 1 hour. Anodizing treatment was performed for a minute. Further, the support 2 was washed with water, sealed with a 2.5% aqueous solution of sodium silicate at 80 ° C. for 20 seconds, and washed with water to prepare a support 2.

(Preparation of Photosensitive Solution) Composition of Photosensitive Solution 1 Diazo resin shown in Table 1 g N- (4-hydroxyphenyl) methacrylamide / ethyl acrylate / methyl acrylate / acrylonitrile / methacrylic acid = 10/52/15/15 / 8 (molar ratio) Copolymer (Mw = 60000) 10 g Polyacrylic acid (Polymerization degree 100) 0.24 g Victoria Pure Blue BOH (Hodogaya Chemical Co., Ltd.) 0.1 g Ethylene glycol monomethyl ether 150 g

Composition of Photosensitive Solution 2 Diazo resin 1 g shown in Table 1 2-hydroxyethyl methacrylate / ethyl methacrylate / benzyl methacrylate / acrylonitrile / acrylic acid = 40/20/10/23/7 (molar ratio) copolymer (Mw = 55000) 10 g Malic acid 0.05 g Oil blue # 603 (Orient Chemical Industry KK) 0.15 g Megafac F-177 (Dainippon Ink and Chemicals, fluorinated surfactant) 0.03 g Ethylene glycol monomethyl ether 100 g Methyl ethyl ketone 50 g

Composition of Photosensitive Solution 3 Diazo resin shown in Table 1 0.2 g N- [2- (methacryloyloxy) ethyl] -2,3-dimethylmaleimide / methacrylic acid = 65/35 (molar ratio) copolymer 5 g Sensitizer represented by the structural formula: 0.25 g

[Chemical 17]

Dipicolinic acid 0.05 g Propylene glycol monomethyl ether 50 g Methyl ethyl ketone 50 g Megafac F-177 0.03 g Oil blue # 603 0.15 g

Composition of photosensitive liquid 4 Diazo resin shown in Table 1 0.2 g β-cinnamoyloxyethyl methacrylate / methacrylic acid = 70/30 (molar ratio) copolymer 5.0 g Sensitizer represented by the following structural formula 0.25g

[Chemical 18]

Dipicolinic acid 0.05 g Propylene glycol monomethyl ether 50 g Methyl ethyl ketone 50 g Megafac F-177 0.03 g Oil blue # 603 0.15 g

Composition of Photosensitive Solution 5 Diazo resin shown in Table 1 0.3 g Allyl methacrylate / benzyl methacrylate / methacrylic acid = 60/20/20 (molar ratio) Copolymer 5 g Trimethylolpropane triacrylate 2.0 g Represented photopolymerization initiator 0.25g

[Chemical 19]

Behenic acid amide 0.2 g Oil blue # 603 0.15 g Malic acid 0.05 g Megafac F-177 0.03 g Ethylene glycol monomethyl ether 100 g Methyl ethyl ketone 50 g Methanol 50 g

Composition of Photosensitive Solution 6 Diazo resin shown in Table 1 0.3 g Allyl methacrylate / methacrylic acid = 60/20/20 (molar ratio) Copolymer 5 g Pentaerythritol tetraacrylate 2.0 g Combination of photoinitiators below Lophine Dimer / Michler's Ketone 0.3 g / 0.3 g p-Methoxyphenol 0.2 g Oil Blue # 603 0.15 g Megameac F-177 0.03 g Ethylene glycol monomethyl ether 100 g Methyl ethyl ketone 50 g Methanol 50 g

Photosensitive solutions 1 to 6 were coated on the above supports 1 to 2 in a combination of Table 1 so that the dry film thickness was 2 g / m ² , dried at 80 ° C. for 2 minutes, and further required. (Listed in Table 1) A polyvinyl alcohol (saponification degree 86 to 89 mol%, polymerization degree 1000 or less) 3% by weight aqueous solution for the overcoat layer is applied so as to have a dry weight of 1.5 g / m ^2. Then, a photosensitive lithographic printing plate sample was obtained.

Example 8 A diazo resin having the following composition was coated on the above-mentioned support 1 so that the dry weight was 10 mg / m ^2, and dried at 80 ° C. for 1 minute to form an intermediate layer. Further on top of this,
The product except the diazo resin was applied in the same manner as in Examples 1 to 7 to obtain a photosensitive lithographic printing plate sample.

Composition of Diazo Resin Liquid Diazo Resin 1 0.1 g Methanol 150 g Pure Water 50 g

(Evaluation of photosensitive lithographic printing plate sample) A negative film original is passed through the obtained photosensitive lithographic printing plate sample, and 2
Exposure was carried out at 8 mW / cm ² for 30 seconds using a kW metal halide lamp, and a developing solution having the following composition was used at 25 ° C. for 3 seconds.
Development was carried out for 0 seconds. The developed sample is Heidelberg G
Printing was performed using a TO printing machine, and the number of sheets until the stain on the paper surface and the plate surface was worn out and printing became impossible were compared, and the developability and printing durability of the photosensitive lithographic printing plate sample were evaluated. The results are shown in Table 1.

Composition of developer Sodium silicate (SiO ₂ / Na ₂ O molar ratio about 1: 1) 20 g Sodium isopropylnaphthalene sulfonate 5 g Pure water 1000 g

[Table 1]

From the above experimental results, the photosensitive lithographic printing plate sample using the diazo resin of the present invention is superior in developability and printing durability as compared with the case of using the conventional diazo resin. Recognize.

[0143]

As described above, according to the present invention, it is possible to obtain a photosensitive lithographic printing plate excellent in developability and printing durability and a photosensitive composition capable of forming such a printing plate.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication location G03F 7/11 (72) Inventor Jiro Uemura 1000 Kamoshida-cho, Midori-ku, Yokohama-shi, Kanagawa Sanryo Kasei Co., Ltd. Corporate Research Institute (72) Inventor Masahisa Murata 1000 Kamoshida-cho, Midori-ku, Yokohama-shi, Kanagawa Sanryo Kasei Co., Ltd.

Claims (4)

[Claims] 1. A photosensitive composition comprising a diazo resin having at least one repeating unit represented by the following general formula (I). [Chemical 1] In the formula, R ¹ represents a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a hydroxy group, a carboxyester group or a carboxyl group, and R ² represents a hydroxy group or at least one alcoholic or phenolic group. Shows a group having a hydroxyl group, R ³ is a hydrogen atom,
Represents an alkyl group or an alkoxy group, R ⁴ represents a hydrogen atom, an alkyl group or an alkoxy group, and X represents —NH
-, -O-, or -S- is shown, and Y ^- is an anion. 2. A photosensitive lithographic printing plate having a photosensitive layer on a support having a hydrophilic surface, the diazo resin having at least one repeating unit represented by the following general formula (I) in the photosensitive layer. A photosensitive lithographic printing plate characterized by containing. [Chemical 2] In the formula, R ¹ represents a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a hydroxy group, a carboxyester group or a carboxyl group, and R ² represents a hydroxy group or at least one alcoholic or phenolic group. Shows a group having a hydroxyl group, R ³ is a hydrogen atom,
Represents an alkyl group or an alkoxy group, R ⁴ represents a hydrogen atom, an alkyl group or an alkoxy group, and X represents —NH
-, -O-, or -S- is shown, and Y ^- is an anion. 3. A light comprising a polymerizable compound having an ethylenically unsaturated bond, a photopolymerization initiator and an alkali-soluble or swellable high-molecular polymer capable of forming a film on a support having a hydrophilic surface. A photosensitive layer formed of a polymerizable substance or a photosensitive lithographic printing plate having such a photosensitive layer and an intermediate layer, wherein the intermediate layer or the photosensitive layer has at least one repeating unit represented by the following general formula (I). A photosensitive lithographic printing plate comprising a diazo resin. [Chemical 3] In the formula, R ¹ represents a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a hydroxy group, a carboxyester group or a carboxyl group, and R ² represents a hydroxy group or at least one alcoholic or phenolic group. Shows a group having a hydroxyl group, R ³ is a hydrogen atom,
Represents an alkyl group or an alkoxy group, R ⁴ represents a hydrogen atom, an alkyl group or an alkoxy group, and X represents —NH
-, -O-, or -S- is shown, and Y ^- is an anion. 4. A photosensitive layer having an alkali-soluble or swelling photocrosslinkable polymer or a photosensitive lithographic printing plate having such a photosensitive layer and an intermediate layer on a support having a hydrophilic surface, wherein the intermediate layer or A photosensitive lithographic printing plate comprising a diazo resin having at least one repeating unit represented by the following general formula (I) in a photosensitive layer. [Chemical 4] In the formula, R ¹ represents a hydrogen atom, an alkyl group which may have a substituent, an alkoxy group, a hydroxy group, a carboxyester group or a carboxyl group, and R ² represents a hydroxy group or at least one alcoholic or phenolic group. Shows a group having a hydroxyl group, R ³ is a hydrogen atom,
Represents an alkyl group or an alkoxy group, R ⁴ represents a hydrogen atom, an alkyl group or an alkoxy group, and X represents —NH
-, -O-, or -S- is shown, and Y ^- is an anion.