JPH1026824A - Photosensitive planographic printing plate and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive planographic printing plate of a negative type with which high image quality suppressed in dot gains is obtainable, and a process for producing the same. SOLUTION: At least one layer among the plural layers of the negative type photosensitive planographic printing plate having the plural layers varying in compsn. on a sheet-like base subjected to a hydrophilicity impartation treatment is a photosensitive layer forming a hydrophilic layer which is made insoluble in a developer by irradiation with active rays and any layer among the upper layers of the hydrophilic photosensitive layers described above is a photosensitive layer forming a hydrophobic layer which is made insoluble in the developer by irradiation with the active rays.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a negative photosensitive lithographic printing plate and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a negative photosensitive lithographic printing plate is obtained by coating a support having a hydrophilic surface with a photosensitive layer which is insolubilized in a developing solution by irradiating with an actinic ray. When a negative film is brought into close contact with this and exposed, and the unexposed portion is removed with a developing solution, the surface of the unexposed portion of the support is exposed, and the exposed portion forms a lipophilic positive image. At this time, it is necessary to provide a certain amount of exposure or more in order to sufficiently insolubilize the image area with a developing solution and further provide sufficient mechanical strength for printing.

However, upon exposure, due to light scattering in the photosensitive layer and diffuse reflection at the photosensitive layer / support interface, the actually obtained image area on the plate becomes larger than the area exposed through the negative film. However, there is a problem that a phenomenon called so-called dot gain occurs. In particular, when a halftone image document or a character document having a small series is used, the deterioration of image quality due to the dot gain becomes a problem. Conventionally, various devices have been devised in order to suppress the dot gain on this plate, but in reality, no satisfactory device has been obtained yet.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a negative photosensitive lithographic printing plate capable of obtaining high image quality with suppressed dot gain, and a method of manufacturing the same.

[0005]

The above objects of the present invention are as follows. On a negative photosensitive lithographic printing plate having a plurality of layers having different compositions on a sheet-shaped support subjected to a hydrophilic treatment, at least one of the plurality of layers is insolubilized in a developing solution by irradiation with actinic rays. A photosensitive layer that forms a hydrophilic layer, and any one of the upper layers of the hydrophilic photosensitive layer becomes insoluble in a developer by irradiation with actinic light, and forms a hydrophobic layer. A photosensitive lithographic printing plate, characterized in that

[0006] 2. The hydrophilic photosensitive layer contains, as constituent components, (A) a photopolymerization initiator composition, (B) a compound having a polymerizable ethylenically unsaturated bond, and (C) a polymer compound capable of forming a film. The above 1 characterized by the above-mentioned.
Described photosensitive lithographic printing plate,

[0007] 3. 3. The photosensitive lithographic printing plate according to the above 2, wherein the polymer compound capable of forming a film (C) is a water-soluble polymer compound.

[0008] 4. 4. The photosensitive material according to item 3, wherein (C) the polymer compound capable of forming a film is a homopolymer of N-vinyl-2-pyridinone and / or a copolymer with another copolymerizable monomer. Lithographic printing plate,

[0009] 5. The photosensitive lithographic printing plate according to any one of 2 to 4, wherein (B) the compound having a polymerizable ethylenically unsaturated bond has an alcoholic hydroxyl group in a molecule.

[0010] 6. (A) a water-soluble or water-dispersible photopolymerization initiator composition, (B) a compound having a water-soluble or water-dispersible polymerizable ethylenically unsaturated bond, (C) The photosensitive lithographic printing plate according to the above 1, wherein the photosensitive lithographic printing plate contains a polymer emulsion dispersible in an aqueous system, as a constituent component.

7. The hydrophobic photosensitive layer contains, as constituent components, (a) a photopolymerization initiator composition, (b) a compound having a polymerizable ethylenically unsaturated bond, and (c) a polymer compound capable of forming a film. The above 1 characterized by the above-mentioned.
A photosensitive lithographic printing plate according to any one of to 6,

8. The hydrophobic photosensitive layer comprises (a) a photopolymerization initiator composition, (b) a compound having a polymerizable ethylenically unsaturated bond, and (c) a polymer emulsion dispersible in an organic solvent system. The photosensitive lithographic printing plate according to any one of the above 1 to 6, characterized by containing as

9. Wherein the hydrophobic photosensitive layer contains a diazo compound as a component.
Photosensitive lithographic printing plate according to any of

10. The photosensitive lithographic printing plate according to any one of 1 to 9, wherein a layer for blocking oxygen is provided on the hydrophobic photosensitive layer.

11. On a sheet-like support that has been subjected to a hydrophilic treatment, a photosensitive layer that is insolubilized in a developer by irradiation with actinic light and forms a hydrophilic layer is provided. And a method for producing a negative photosensitive lithographic printing plate, characterized in that a photosensitive layer for forming a hydrophobic layer is provided.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. [Support] Aluminum is preferable as the support used in the present invention, and the aluminum support includes a support made of pure aluminum and an aluminum alloy. Various aluminum alloys can be used,
For example, an alloy of aluminum with a metal such as silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth, and nickel is used.

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

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

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

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

After the anodizing treatment, the support is subjected to a surface treatment such as a treatment with an alkali silicate, hot water, or the like, or a dipping in a water-soluble polymer compound such as polyvinylphosphonic acid or an aqueous solution of potassium fluorozirconate. Is preferably performed.

[Photosensitive composition] The present invention is a negative photosensitive lithographic printing plate having a plurality of layers having different compositions on the surface-treated support, wherein at least one of the plurality of layers is provided. A photosensitive layer that is insoluble in a developer by irradiation with actinic rays and forms a hydrophilic layer (hereinafter, also referred to as a hydrophilic photosensitive layer), and any one of the upper layers of the hydrophilic photosensitive layer. The photosensitive layer is a photosensitive layer in which a layer is insoluble in a developer by irradiation with actinic rays and forms a hydrophobic layer (hereinafter, also referred to as an oleophilic photosensitive layer).

In the present invention, the photosensitive system for both the hydrophilic photosensitive layer and the lipophilic photosensitive layer can be a photopolymerizable system or a diazo resin system.

The hydrophilic photosensitive layer may comprise (A) a photopolymerization initiator composition, (B) a compound having a polymerizable ethylenically unsaturated bond, and (C) a film-forming compound. A polymer compound as a component, and in particular, (C) a polymer compound capable of forming a film,
Preferably a water-soluble polymer compound, more specifically N-
More preferably, it is a homopolymer of vinyl-2-pyridinone and / or a copolymer with another copolymerizable monomer. Further, (B) the compound having a polymerizable ethylenically unsaturated bond preferably has an alcoholic hydroxyl group in the molecule.

Alternatively, the hydrophilic photosensitive layer may comprise (A) a water-soluble or water-dispersible photopolymerization initiator composition, and (B) a water-soluble or water-dispersible polymerizable ethylenic compound. The composition contains a compound having an unsaturated bond and (C) a polymer emulsion dispersible in an aqueous system as constituent components.

The hydrophobic photosensitive layer may comprise (a) a photopolymerization initiator composition, (b) a compound having a polymerizable ethylenically unsaturated bond, and (c) a film-formable film. A polymer compound as a component, or (a) a photopolymerization initiator composition, (b) a compound having a polymerizable ethylenically unsaturated bond, and c) a polymer emulsion that can be dispersed in an organic solvent system.

Hereinafter, the photosensitive composition used in the photosensitive lithographic printing plate of the present invention will be described.

[Diazo compound] The diazo compound in the photosensitive composition is, for example, a diazo resin represented by a condensate of an aromatic diazonium salt with formaldehyde or acetaldehyde. Particularly preferably, a salt of a condensate of p-diazophenylamine with formaldehyde or acetaldehyde, for example, the reaction product of the above condensate with hexafluoroborate, tetrafluoroborate, perchlorate or periodate Diazo resin inorganic salt,
Examples thereof include an organic salt of a diazo resin which is a reaction product of the condensate and a sulfonic acid as described in US Pat. No. 3,300,309. Furthermore, diazo resins are preferably used with binders. As such a binder, various polymer compounds can be used. Preferably, a monomer having an aromatic hydroxyl group, such as N- (4), described in JP-A-54-98613 is used. -Hydroxyphenyl) acrylamide, N
-(4-hydroxyphenyl) methacrylamide, o
-, M-, or p-hydroxystyrene, o-, m
-Or a copolymer of p-hydroxyphenyl methacrylate or the like with another monomer, U.S. Pat. No. 4,123,27
No. 6,751,257, a polymer containing a hydroxyethyl acrylate unit or a hydroxyethyl methacrylate unit as a main repeating unit, a natural resin such as shellac, rosin, polyvinyl alcohol, and the like described in the specification of US Pat. Linear polyurethane resin as described in the specification, phthalated resin of polyvinyl alcohol, epoxy resin condensed from bisphenol A and epichlorohydrin, cellulose acetate,
Cellulose derivatives such as cellulose acetate phthalate are included.

Further, the diazo compound is preferably a co-condensation resin of diazodiphenylamine and an aromatic compound having at least one group selected from a carbonyl group and a sulfonyl group in the molecule. The cocondensation ratio is a diazodiphenylamine / aromatic compound = 30/70 to 95/5 in a molar ratio, particularly preferably a cocondensate of diazodiphenylamine and p-hydroxybenzoic acid, and a molar ratio of 50/70. 50 to 80/20.

In the present invention, a particularly preferred diazo compound is a condensation resin of an aromatic diazonium compound and a carbonyl compound. In this condensation resin, it is preferable to use a diazo resin having a structure represented by the following general formula (1) or (2).

[0031]

Embedded image [In the formula, R represents a hydrogen atom, an alkyl group, or a phenyl group, R ¹ , R ^2, and R ³ each represent a hydrogen atom, an alkoxy group, or an alkyl group, and X represents a counter anion. Y represents -NH-, -O- or -S-. n represents an integer. ]

[0032]

Embedded image [Wherein, A represents a condensable aromatic group, and R, R ¹ ,
R ² , R ³ , X, Y, and n have the same meanings as those used in formula (1). ]

As the aromatic diazonium compound as a structural unit of the diazo resin represented by the general formulas (1) and (2), for example, a diazonium salt such as that described in JP-B-49-48001 may be used. Of these, diphenylamine-4-diazonium salts are particularly preferred. Diphenylamine-4-diazonium salts are derived from 4-aminodiphenylamines, such as 4-aminodiphenylamine, 4-aminodiphenylamine, 4-amino-3-methoxydiphenylamine, and 4-amino-2-amine. Methoxydiphenylamine, 4 '
-Amino-2-methoxydiphenylamine, 4'-amino-4-methoxydiphenylamine, 4-amino-3-
Methyldiphenylamine, 4-amino-3-ethoxydiphenylamine, 4-amino-3- (β-hydroxyethoxy) diphenylamine, 4-aminodiphenylamine-2-sulfonic acid, 4-aminodiphenylamine-2
-Carboxylic acid, 4-aminodiphenylamine-2'-carboxylic acid, and the like. Of these, particularly preferred are 4-aminodiphenylamine,
-Amino-3-methoxydiphenylamine.

In the general formula (2), specific examples of the aromatic compound which can be used to give the aromatic group represented by A include m-chlorobenzoic acid, diphenylacetic acid, phenoxyacetic acid, -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, phenol, cresol, xylenol, resorcin, 2-methylresorcin, methoxyphenol, 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-hydroxy Acetophenone, 4,4
'-Dihydroxydiphenyl ether, 4,4'-dimethoxydiphenylether, 4,4'-dihydroxydiphenylamine, 4,4'-dihydroxydiphenylsulfide, cumylphenol, chlorophenol, bromophenol, salicylic acid, p-hydroxybenzoic acid,
2-methyl-4-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 3,
5-dihydroxybenzoic acid, 4-chloro-2,6-dihydroxybenzoic acid, 4-methoxy-2,6-dihydroxybenzoic acid, gallic acid, phloroglysin carboxylic acid, N
-(4-hydroxyphenyl) methacrylamide, N-
(4-hydroxyphenyl) acrylamide, cinnamic acid,
Methyl cinnamate, ethyl cinnamate, p-hydroxycinnamic acid,
Styrene, hydroxystyrene, stilbene, 4-hydroxystilbene, 4,4'-dihydroxystilbene, 4-carboxystilbene, 4,4'-dicarboxystilbene, diphenolether, diphenylamine, diphenylthioether, 4-methoxydiphenylether, 4- Methoxydiphenylamine, 4-methoxydiphenylthioether and the like can be mentioned.

The above diazo resin can be prepared by a known method, for example,
Photographic Science and Engineering (Photo. Sci. Eng.) Vol. 17, p. 33 (1973), U.S. Pat. No. 2,063,631,
2,679,498, JP-B-49-480
No. 01, aromatic diazonium salt, an aromatic compound giving an aromatic group represented by A in the above general formula (2) and an active carbonyl compound in sulfuric acid, phosphoric acid or hydrochloric acid according to the method described in JP-A-01 For example, it can be obtained by polycondensing paraformaldehyde, acetaldehyde, benzaldehyde, acetone, acetophenone, or the like.

The counter anion of the diazo resin is preferably one that forms a salt with the diazo resin stably. In the case of a diazo resin applied to the lipophilic photosensitive layer, an anion that makes the resin soluble in an organic solvent is preferable. In the case of a diazo resin applied to the lipophilic photosensitive layer, an anion that makes the resin soluble in an organic solvent is preferable. Examples of the acid forming such an anion include organic carboxylic acids such as decanoic acid and benzoic acid,
Organic phosphoric acids such as phenylphosphoric acid, including organic sulfonic acids, typical examples include methanesulfonic acid, chloroethanesulfonic acid, dodecanesulfonic acid, benzenesulfonic acid,
Aliphatic sulfonic acids such as toluenesulfonic acid, mesitylenesulfonic acid, anthraquinonesulfonic acid, naphthylsulfonic acid, and alkyl-substituted naphthylsulfonic acid, and halogenated Lewis acids such as aromatic sulfonic acid, hexafluorophosphoric acid, and tetrafluoroboric acid, and perchloric acid Examples thereof include perhalic acids such as acid and periodic acid. However, it is not limited to this. Among them, particularly preferred are hexafluorophosphoric acid, tetrafluoroboric acid and mesitylenesulfonic acid. In the case of a diazo resin applied to the hydrophilic photosensitive layer, an anion that makes the resin water-soluble is preferable. Sulfuric acid and hydrochloric acid are typical examples of the acid forming such an anion.

In the present invention, the molecular weight of the diazo resin used is not particularly limited.
By variously changing the molar ratio of each monomer and the condensation conditions, the molecular weight can be obtained as an arbitrary value,
In the present invention, it is generally preferred that the molecular weight be about 400 to
10,000 can be effectively used, and more preferably about 800 to 5,000. The amount of these diazo compounds contained in the photosensitive composition is 0%.
To 30% by weight, more preferably 0.5 to 2% by weight.
0% by weight.

(Polymer compound capable of forming a film) Among the polymer compounds capable of forming a film according to the present invention, the one used in the lipophilic photosensitive layer contains a lipophilic polymer compound that functions as a binder. Can be.
As the lipophilic polymer compound as the binder that can be used in the present invention, any compound can be used, for example, polyamide, polyether, polyester, polycarbonate, polystyrene, polyurethane,
Examples include polyvinyl chloride and its copolymer, polyvinyl butyral resin, polyvinyl formal resin, shellac, epoxy resin, phenol resin, and acrylic resin. Among those preferably used in these,
Copolymers of monomers selected from the following monomers (1) to (12) may be mentioned.

(1) A monomer having an aromatic hydroxyl group, for example, N- (4-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide, o-hydroxystyrene, p-hydroxystyrene, m-hydroxystyrene , O-hydroxyphenyl acrylate, p-hydroxyphenyl acrylate,
m-hydroxyphenyl acrylate and the like.

(2) Monomers having an aliphatic hydroxyl group, for example, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, N-methylol acrylamide, N-methylol methacrylamide, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, 5-hydroxypentyl acrylate, 5-hydroxypentyl methacrylate, 6-hydroxyhexyl acrylate, 6-hydroxyhexyl methacrylate, N- (2-hydroxyethyl) acrylamide,
N- (2-hydroxyethyl) methacrylamide, hydroxyethyl vinyl ether and the like.

(3) Monomers having an aminosulfonyl group, for example, m-aminosulfonylphenyl methacrylate, p-aminosulfonylphenyl methacrylate,
m-aminosulfonylphenyl acrylate, p-aminosulfonylphenyl acrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- (p-aminosulfonylphenyl) acrylamide and the like.

(4) Monomers having an unsaturated sulfonamide, for example, N- (p-toluenesulfonyl) acrylamide, N- (p-toluenesulfonyl) methacrylamide and the like.

(5) α, β-unsaturated carboxylic acids, for example, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride and the like.

(6) A substituted or unsubstituted alkyl acrylate, for example, methyl acrylate, ethyl acrylate,
Propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonyl acrylate, decyl acrylate, undecyl acrylate, dodecyl acrylate, benzyl acrylate, cyclohexyl acrylate, acrylic acid -2-chloroethyl, N, N-dimethylaminoethyl acrylate, glycidyl acrylate and the like.

(7) Substituted or unsubstituted alkyl methacrylates, for example, methyl methacrylate, ethyl methacrylate, propyl methacrylate, amyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate, methacrylic acid Decyl, undecyl methacrylate, dodecyl methacrylate,
Benzyl methacrylate, cyclohexyl methacrylate,
2-chloroethyl methacrylate, N, N-dimethylaminoethyl methacrylate, glycidyl methacrylate and the like.

(8) Acrylamide or methacrylamide, for example, acrylamide, methacrylamide, N-ethylacrylamide, N-hexylacrylamide, N-cyclohexylacrylamide, N-phenylacrylamide, N-nitrophenylacrylamide, N-ethyl-N -Phenylacrylamide and the like.

(9) Monomers containing a fluoroalkyl group, for example, trifluoroethyl acrylate, trifluoroethyl methacrylate, tetrafluoropropyl acrylate, tetrafluoropropyl methacrylate, hexafluoropropyl methacrylate, octafluoropentyl acrylate, octafluoropentyl Methacrylate, heptadecafluorodecyl acrylate, heptadecafluorodecyl methacrylate, N-butyl-N- (2-acryloxyethyl) heptadecafluorooctylsulfonamide and the like.

(10) Vinyl ethers such as ethyl vinyl ether, 2-chloroethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether and phenyl vinyl ether.

(11) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate and vinyl benzoate.

(12) Styrenes such as styrene, methylstyrene and chloromethylstyrene.

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

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

(15) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine and the like.

(16) A cyano group-containing monomer, for example,
Acrylonitrile, methacrylonitrile, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethylacrylate, o-cyanostyrene, m-cyanostyrene, p-cyanostyrene and the like.

Further, a monomer copolymerizable with the above-mentioned monomer may be copolymerized. In addition, a copolymer obtained by copolymerization of the above-mentioned monomers may be modified with, for example, glycidyl acrylate, glycidyl methacrylate, or the like, but is not limited thereto.

The monomer to be used is arbitrary in the above-mentioned monomer group. However, when a general alkaline aqueous solution-based developer is used, a copolymer of a carboxylic acid and another monomer listed in the above-mentioned monomer group (5) is used. It is preferred that they are united. In this case, the copolymerization ratio of the carboxylic acid and the other monomer is preferably such that the carboxylic acid-containing monomer is in the range of 1 to 30 mol% of the whole. The molecular weight of the above copolymer was determined by gel permeation chromatography (G
PC). The weight average is preferably 10,000 to 200,000, but is not limited thereto.

Further, as another suitably used high molecular compound, polyurethane is alkali-solubilized,
4-19773, JP-A-57-94747, 60
Nos. -182437, 62-58242, 62-12
No. 3452, No. 62-123453, No. 63-113
No. 450 and the polymer compounds described in JP-A-2-14642 are also useful.

The lipophilic polymer compound contained in the photosensitive composition used in the photosensitive layer of the photosensitive lithographic printing plate of the present invention is preferably 30 to 95% by weight in the solid component of the photosensitive composition. To be included. If necessary, an arbitrary resin such as a polyvinyl butyral resin, a polyurethane resin, a polyamide resin, a polyester resin, an epoxy resin, a novolak resin, and a natural resin may be added.

The hydrophilic photosensitive layer is preferably a water-soluble polymer compound, especially a homopolymer of N-vinyl-2-pyridinone and / or a copolymer with another copolymerizable monomer. Examples of the copolymerizable monomer include the above-mentioned monomers (1) to (12).

[Compound having an addition-polymerizable unsaturated bond]
Compound having an addition-polymerizable unsaturated bond used in the photosensitive composition of the present invention (hereinafter, referred to as a photopolymerizable monomer).
Is not particularly limited, a conventionally known compound can be used, and a compound having one addition-polymerizable unsaturated bond in a molecule (hereinafter, referred to as a compound having one or more
It is called a monofunctional monomer. ) Or a compound having a plurality of compounds (hereinafter, referred to as a polyfunctional monomer). The addition-polymerizable unsaturated bond contained in the molecule is preferably an acryloyl group or a methacryloyl group.

Examples of the monofunctional monomer include linear or cyclic alkyl (meth) acrylate, aromatic alcohol (meth) acrylate, polyhydric alcohol mono (meth) acrylate, polyethylene oxide (meth) acrylate, and polypropylene oxide. (Meth) acrylate, fluorinated alkyl (meth) acrylate, glycidyl (meth) acrylate, hydroxy group-containing alkyl (meth) acrylate, alkoxy group-containing alkyl (meth) acrylate, and the like.

As the polyfunctional monomer, a compound obtained by introducing an addition-polymerizable unsaturated bond into a polyhydric alcohol or a high phenol is preferably used. As a method for introducing an addition-polymerizable unsaturated bond into a polyhydric alcohol or a polyhydric phenol, a method for introducing an acryloyl group or a methacryloyl group into a polyhydric alcohol or a polyhydric phenol through an ester bond is mentioned first. Polyhydric alcohols that can be used in this method include, for example, chain or cyclic alkanediol, polyethylene oxide, polypropylene oxide, alkanediol modified with ethylene oxide, alkanediol modified with propylene oxide, and modified with ethylene oxide. Polyhydric phenols, polyhydric phenols modified with propylene oxide, bisphenols modified with ethylene oxide, bisphenols modified with propylene oxide, condensates of polyethylene oxide and polypropylene oxide, glycerol, trimethylolpropane,
Pentaerythritol, dipentaerythritol, diglycerol, triglycerol, trishydroxyethyl isocyanurate and the like are preferably used.

Compounds obtained by introducing two or more acryloyl groups or methacryloyl groups into polyols obtained by modifying the hydroxyl groups of these polyhydric alcohols with ethylene oxide, polyethylene oxide, propylene oxide, polypropylene oxide, epichlorohydrin, caprolactone, etc. are also preferable. Can be used.

As other examples, the above-mentioned polyhydric alcohols are reacted with an isocyanate group-containing (meth) acrylate such as acryloyloxyethyl isocyanate and methacryloyloxyethyl isocyanate, or 2-hydroxyethyl (meth) is added to a high isocyanate compound. Urethane acrylates obtained by reacting a hydroxyl group-containing (meth) acrylate such as acrylate can also be mentioned. Further, derivatives of acryloyloxyethyl ester and methacryloyloxyethyl ester of phosphoric acid can also be used.

In addition to the above examples, "UV / EB Curing Handbook-Raw Material Edition", edited by Kiyoso Kato (Polymer Publishing Association)
Pp. 11-65, “Applications and Markets of UV / EB Curing Technology”
Photopolymerizable monomers / oligomers described on pages 7 to 55 of Yoneho Tabata, edited by Radotech Kenkyukai (CMC) can also be used.

The specific examples of the photopolymerizable monomers are those which can be used in the present invention, and the photopolymerizable monomers which can be used in the present invention include:
It is not limited by the above specific example. Further, a plurality of these photopolymerizable monomers can be used in combination in the photosensitive composition. The content of the photopolymerizable monomer in the photosensitive composition part is preferably in the range of 5 to 80% by weight,
More preferably, it is in the range of 10 to 50% by weight.

The compound having an addition-polymerizable unsaturated bond can be applied to both the lipophilic photosensitive layer and the hydrophilic photosensitive layer. Particularly, in the hydrophilic photosensitive layer, a compound having water solubility is desirable.

[Photopolymerization initiator] Examples of the photopolymerization initiator applicable to the lipophilic photosensitive layer include photopolymerization initiators generally known in this technical field, for example, benzoin derivatives such as benzoin methyl ether, and benzophenones such as benzophenone. Derivatives, thioxanthone derivatives, anthraquinone derivatives, acridone derivatives and the like can be mentioned, but as described in claim 2, preferably, the following general formula (I)
It contains at least one of the compounds having the structures represented by I), general formula (III), and general formula (IV).

[0069]

Embedded image In the formula, Ar represents a substituted or unsubstituted phenylene group, naphthylene group or heterocyclic aromatic group, and R ⁵ represents a hydrogen atom, an alkyl group, an alkoxy group, a dialkylamino group, an alkylthio group, a hydroxy group, a halogen, —COOR ⁶ , -O
— (CH ₂ ) _d —COOR ⁶ ,

[0070]

Embedded image ^{-R 8 -COOR 6, -R 8 -CONHR} 6, -NHC
OR ⁹ (R ⁶ represents a hydrogen atom, an alkyl group, a substituted alkyl group, an aryl group, or a substituted aryl group; R ⁷ represents a hydrogen atom or a methyl group; R ⁸ represents an alkylene group; R ⁹ represents an alkyl group; A, a substituted alkyl group, an alkoxy group, an aryl group, or a substituted aryl group, wherein d and e are 1 to
Indicates an integer of 10. ), B represents an integer of 0 to 2, X represents a halogen, c and d each represent an integer of 0 to 3, but c +
d ≦ 5.

[0071]

Embedded image In the formula, R ¹⁰ and R ¹¹ represent an alkyl group or a halogen,
f and g show the integer of 0-4.

[0072]

Embedded image In the formula, R ¹² and R ¹³ represent a hydrogen atom and a dialkylamino group.

Specific examples of the compound having the structure represented by the general formula (II) include the following.

[0074]

Embedded image

[0075]

Embedded image

[0076]

Embedded image

Specific examples of the compound having the structure represented by the general formula (III) include 2-chlorothioxanthone, 2,4-dimethylthioxanthone, and 2,4-dimethylthioxanthone.
Examples thereof include diethylthioxanthone, 2,4-diisopropylthioxanthone, and isopropylthioxanthone.

The content of the photopolymerization initiator in the photosensitive composition is preferably in the range of 0.2 to 15% by weight.
More preferably, it is in the range of 0.5 to 10% by weight.

The photopolymerization initiator applicable to the hydrophilic photosensitive layer preferably has water solubility. Examples of preferable compounds include Kayacure Q manufactured by Nippon Kayaku Co., Ltd.
Examples include thioxanthone containing a quaternary ammonium salt such as TX, and a combination of these compounds with a water-soluble tertiary amine such as triethanolamine is preferably used.

[Alkali-soluble resin] Examples of the alkali-soluble resin include novolak resins, vinyl polymers having a phenolic hydroxyl group, and condensation of polyhydric phenols and aldehydes or ketones described in JP-A-55-57841. Resins.

The novolak resins usable in the present invention include, for example, phenol-formaldehyde resin, cresol-formaldehyde resin, and JP-A-55-57841.
Phenol-cresol-formaldehyde copolymer resin as described in JP-A-55-127
No. 553, a copolymer resin of p-substituted phenol and phenol, or cresol and formaldehyde.

The molecular weight (polystyrene standard) of the novolak resin is preferably such that the number average molecular weight Mn is 3.00 ×
10 ^{2 to} 7.50 × 10 ³ , and a weight average molecular weight Mw of 1.
00 × 10 ^{3 to} 3.00 × 10 ⁴ , more preferably Mn
Is 5.00 × 10 ^{2 to} 4.00 × 10 ³ , and Mw is 3.0
It is 0 × 10 ^{3 to} 2.00 × 10 ⁴ . The novolak resins may be used alone or in combination of two or more. The proportion of the novolak resin in the photosensitive composition is preferably from 5 to 95% by weight. The vinyl copolymer having a phenolic hydroxyl group preferably used in the present invention is a polymer having a unit having the phenolic hydroxyl group in a molecular structure, and has the following general formulas [I] to [V].
Preferred are polymers containing at least one structural unit of

[0083]

Embedded image

[Wherein R ₁ and R ₂ each represent a hydrogen atom, an alkyl group or a carboxyl group, preferably a hydrogen atom. R ₃ represents a hydrogen atom, a halogen atom or an alkyl group, preferably a hydrogen atom or an alkyl group such as a methyl group or an ethyl group. R ₄ represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, preferably a hydrogen atom. A represents an optionally substituted alkylene group which connects a nitrogen atom or an oxygen atom to an aromatic carbon atom; m represents an integer of 0 to 10;
Represents a phenylene group which may have a substituent or a naphthylene group which may have a substituent. ]

The polymer used in the present invention is preferably a polymer having a copolymer type structure, and the polymer represented by the general formula [I]
Examples of the monomer unit that can be used in combination with the structural unit represented by any one of formulas [V] to [V] include ethylenically unsaturated orylenes such as ethylene, propylene, isobutylene, butadiene, and isoprene; Styrenes such as methylstyrene, p-methylstyrene and p-chlorostyrene; for example, acrylic acids such as acrylic acid and methacrylic acid; for example, unsaturated aliphatic dicarboxylic acids such as itacone, maleic acid, and maleic anhydride;
For example, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, Α such as ethyl methacrylate
-Esters of methylene aliphatic monocarboxylic acid, for example, nitriles such as acrylonitrile and methacrylonitrile, for example, amides such as acrylamide, for example, acrylanilide, p-chloroacrylanilide, m-nitroacrylanilide, m-methoxyacrylanilide and the like Anilides such as vinyl acetate, vinyl propionate,
Vinyl esters such as vinyl benzoate and vinyl acetate;
For example, methyl vinyl ether, ethyl vinyl ether,
Vinyl ethers such as isobutyl vinyl ether and β-chloroethyl vinyl ether, vinyl chloride, vinylidene chloride, vinylidene cyanide, for example, 1-methyl-1-methoxyethylene, 1,1-dimethoxyethylene, 1,2-dimethoxyethylene, 1,1 Ethylene derivatives such as -dimethoxycarbonylethylene and 1-methyl-1-nitroethylene, for example, N-vinylpyrrole, N
-N-vinyl monomers such as vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidene and N-vinyl pyrrolidone. These vinyl monomers exist in a polymer compound in a structure in which an unsaturated double bond is cleaved.

Of the above-mentioned monomers, esters and nitriles of aliphatic monocarboxylic acids exhibit excellent performance for the purpose of the present invention and are preferred. These monomers may be bonded to the polymer used in the present invention in either a block or random state.

The vinyl copolymer used in the present invention is not limited to the above, and other vinyl copolymers may be used in combination with the above vinyl copolymer.

The proportion of the vinyl polymer used in the present invention in the photosensitive composition is preferably from 30 to 95% by weight. As the vinyl polymer, the above polymers may be used alone or in combination of two or more. or,
It can also be used in combination with other polymer compounds and the like.

[Compound that Generates Acid by Exposure] Examples of the compound that generates an acid by exposure that can be used in the photosensitive composition include a halomethyloxadiazole compound and a halomethyl-s-triazine compound. Can be A halomethyloxadiazole compound is a compound having a halomethyl group, preferably a trichloromethyl group, in oxadiazoles.

These compounds are known, for example, JP-B-57-6096 and JP-B-61-51788.
JP-B-1-28369, JP-A-60-13853
No. 9, No. 60-177340, No. 60-24
No. 1049, for example. Further, a halomethyl-s-triazine compound is a compound having one or more halomethyl groups, preferably a trichloromethyl group, in an s-triazine ring. Examples of the compound capable of generating an acid upon exposure include o-naphthoquinonediazide-4-sulfonic acid halogenide described in JP-A-50-36209 and o-naphthalene described in JP-A-53-36223. Ester compounds or amide compounds of naphthoquinonediazide-4-sulfonic acid chloride and phenols having an electron-withdrawing substituent or aniline acid, described in JP-A-55-77742, JP-A-57-148784 and the like. Halomethylvinyloxadiazole compounds and diazonium salts.

The amount of the compound that generates an acid upon exposure to light in the photosensitive composition is preferably 0.01 to 30% by weight, more preferably 0.1 to 10% by weight, and particularly preferably 0.2 to 3% by weight. These compounds can be used alone or in combination of two or more.

[Oil Sensitizing Agent] The photosensitive composition of the present invention may contain an oil sensitizing agent. The sensitizing agent enhances the lipophilicity of the photosensitive layer surface, and includes, for example, an ester of p-hydroxystyrene and a fatty acid, a half-ester compound of a styrene-maleic anhydride copolymer with an alcohol, and a long-chain alkyl group-containing compound. Novolak resins, fluorine-based surfactants, etc. are preferred, and preferred are esters of p-hydroxystyrene and a fatty acid, half-ester compounds of styrene-maleic anhydride copolymer with alcohols, and novolak resins containing a long-chain alkyl group. Among them, a long-chain alkyl group-containing novolak resin (alkyl-substituted phenol resin) is particularly preferable. The amount added varies depending on the intended use and purpose, but is generally 0.01 to
30% by weight. The alkyl-substituted phenol resin is a resin obtained by polycondensation of an alkyl-substituted phenol with an aldehyde. The alkyl-substituted phenol used herein may have any position at which alkyl is substituted and the number of substituents, and particularly preferably a structure having one alkyl group at the 4-position. The structure of the alkyl group may be any of a chain, a branch, and a ring, and the number of carbon atoms constituting the alkyl group is arbitrary. An alkyl group having 1 to 20 carbon atoms is preferable. These alkyl-substituted phenols may have other substituents on the aromatic ring. In addition, when polycondensing an alkyl-substituted phenol with an aldehyde, co-condensation can be preferably performed by adding an unsubstituted phenol.

[Organic acid / inorganic acid / acid anhydride] The photosensitive composition may contain an organic acid / inorganic acid / acid anhydride. Examples of the acid used in the present invention include, for example,
No.-88942, Japanese Patent Application No. 63-293107, and an organic acid described in Chemical Society of Japan, edited by The Chemical Society of Japan, Maruzen Publishing.
Inorganic acids described on pages 92 to 158; Examples of the organic acid include sulfonic acids such as p-toluenesulfonic acid, dodecylbenzenesulfonic acid, mesitylenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, and m-benzenedisulfonic acid, and p-toluenesulfonic acid. , Benzylsulfinic acid, sulfinic acid such as methanesulfinic acid, phenylphosphonic acid, methylphosphonic acid, phosphonic acid such as chloromethylphosphonic acid, formic acid,
Acetic acid, propionic acid, butyric acid, isobutyric acid, pentanoic acid, hexanoic acid, aliphatic monocarboxylic acids such as heptanoic acid, alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid, benzoic acid, o-, m-, p-hydroxy Benzoic acid, o-, m
-, Aromatic monocarboxylic acids such as p-methoxybenzoic acid, o-, m-, p-methylbenzoic acid, 3,5-dihydroxybenzoic acid, phloroglysine carboxylic acid, gallic acid and 3,5-dimethylbenzoic acid Is mentioned. Also, saturated or unsaturated aliphatic dicarboxylic acids such as malonic acid, methylmalonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, itaconic acid and malic acid , Tetrahydrophthalic acid, 1,1-cyclobutanedicarboxylic acid, 1,1-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,1-cyclohexanedicarboxylic acid,
Examples thereof include alicyclic dicarboxylic acids such as 1,2-cyclohexanedicarboxylic acid and 1,3-cyclohexanedicarboxylic acid, and aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid.

Of the above organic acids, more preferred are p
-Toluenesulfonic acid, dodecylbenzenesulfonic acid,
Examples thereof include sulfonic acids such as mesitylenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, and m-benzenedisulfonic acid, and cis-1,2-cyclohexanedicarboxylic acid and syringic acid. Examples of the inorganic acid include nitric acid, sulfuric acid, hydrochloric acid, silicic acid, phosphoric acid, and the like, and more preferably, sulfuric acid and phosphoric acid.

When an acid anhydride is used, the type of the acid anhydride is also arbitrary, and those derived from aliphatic / aromatic monocarboxylic acids such as acetic anhydride, propionic anhydride, and benzoic anhydride, and succinic anhydride , Maleic anhydride, glutaric anhydride, phthalic anhydride, etc., and those derived from aliphatic / aromatic dicarboxylic acids. Preferred acid anhydrides are glutaric anhydride and phthalic anhydride. These compounds can be used alone or in combination of two or more. The content of these acids is generally from 0.05 to 5% by weight, preferably from 0.1 to 3% by weight, based on the total solids of the entire photosensitive composition.

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

Examples of the amphoteric surfactant include lauryl dimethylamine oxide, lauryl carboxymethyl hydroxyethyl, imidazolinium betaine and the like.
Examples of anionic surfactants include fatty acid salts, alkyl sulfate salts, alkyl benzene sulfonates, alkyl naphthalene sulfonates, alkyl sulfosuccinates,
Examples thereof include alkyl diphenyl ether disulfonate, alkyl phosphate, polyoxyethylene alkyl sulfate, polyoxyethylene alkyl allyl sulfate, naphthalene sulfonic acid formalin condensate, and polyoxyethylene alkyl phosphate. Examples of the cationic surfactant include an alkylamine salt, a quaternary ammonium salt, and an alkyl betaine. As nonionic surfactants, polyoxyethylene alkyl ether,
Polyoxyethylene alkyl allyl ether, polyoxyethylene derivative, oxyethylene / oxypropylene block copolymer, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, glycerin fatty acid ester, polyoxyethylene fatty acid ester, polyoxy Examples include ethylene alkylamine and alkyl alkanolamide.

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

[Dye] A dye can be further used in the photosensitive composition. The dye is used for the purpose of obtaining a visible image by exposure (exposure visible image) and a visible image after development.

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

On the other hand, examples of the color changing agent which changes from colorless to colored include leuco dyes and, for example, triphenylamine, diphenylamine, o-chloroaniline, 1,2,3-triphenylguanidine, naphthylamine, diaminodiphenylmethane, p, p '-Bis-dimethylaminodiphenylamine, 1,2-dianilinoethylene, p, p',
p "-tris-dimethylaminotriphenylmethane,
p, p'-bis-dimethylaminodiphenylmethylimine, p, p ', p "-triamino-o-methyltriphenylmethane, p, p'-bis-dimethylaminodiphenyl-4-anilinonaphthylmethane, Primary or secondary arylamine dyes represented by p ', p "-triaminotriphenylmethane are exemplified. The proportion of the above-mentioned color changing agent in the photosensitive composition is preferably from 0.01 to 10% by weight, more preferably from 0.02 to 10% by weight.
Used at 5% by weight. These compounds can be used alone or in combination of two or more. Particularly preferred pigments are Victoria Pure Blue BOH and Oil Blue # 6.
03.

[Solvent] Solvents that can be used for dissolving the photosensitive composition include methanol, ethanol, n-propanol, iso-propanol, n-butanol,
aliphatic alcohols such as n-pentanol and hexanol, allyl alcohol, benzyl alcohol, anisole, phenetole, n-hexane, cyclohexane, heptane, octane, nonane, hydrocarbons such as decane, diacetone alcohol, 3-methoxy- 1-butanol,
4-methoxy-1-butanol, 3-ethoxy-1-butanol, 3-methoxy-3-methyl-1-butanol, 3-methoxy-3-ethyl-1-pentanol-
4-ethoxy-1-pentanol, 5-methoxy-1-
Hexanol, acetone, methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl isobutyl ketone, methyl pentyl ketone, methyl hexyl ketone,
Ethyl butyl ketone, dibutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, γ-
Butyrolactone, 3-hydroxy-2-butanone, 4-
Hydroxy-2-butanone, 4-hydroxy-2-pentanone, 5-hydroxy-2-pentanone, 4-hydroxy-3-pentanone, 6-hydroxy-2-hexanone, 3-methyl-3-hydroxy-2-pentanone, Ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, ethylene glycol monoacetate, ethylene glycol diacetate, propylene glycol monoacetate, propylene glycol diacetate, ethylene glycol alkyl ethers and their acetates (methyl cellosolve, ethyl cellosolve) , Butyl cellosolve, phenyl cellosolve, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol Distearate ether, methyl cellosolve acetate, ethyl cellosolve acetate), diethylene glycol monoalkyl ethers and acetates thereof (diethylene glycol monomethyl ether, monoethyl ether, mono-i- propyl ether,
Monobutyl ether, diethylene glycol monomethyl ether acetate, etc.), diethylene glycol dialkyl ethers (DMDG, DEDG, DBDG, ME
DG), triethylene glycol alkyl ethers (monomethyl ether, monoethyl ether, dimethyl ether, diethyl ether, methyl ethyl ether, etc.), propylene glycol alkyl ethers and their acetates (monomethyl ether, monoethyl ether, n-propyl ether, Butyl ether, dimethyl ether, diethyl ether, monomethyl ether acetate, monoethyl ether acetate, etc.), dipropylene glycol alkyl ethers (monomethyl ether, monoethyl ether, n-propyl ether, monobutyl ether, dimethyl ether, diethyl ether), ethyl formate, formic acid Propyl, butyl formate,
Amyl formate, methyl acetate, ethyl acetate, propyl acetate,
Carboxylic esters such as butyl acetate, methyl propionate, ethyl propionate, methyl butyrate, and ethyl butyrate, dimethylformamide, dimethyl sulfoxide, dioxane, tetrahydrofuran, methyl lactate, ethyl lactate, methyl benzoate, ethyl benzoate, propylene carbonate, etc. Is mentioned. These solvents can be used alone or in combination of two or more.

[Coating Layer] In the photosensitive lithographic printing plate, a coating layer composed of a water-insoluble organic solvent-soluble polymer compound having a film-forming ability can be formed on the photosensitive layer.
On the surface of the photosensitive layer provided as described above, shorten the time of evacuation at the time of close contact exposure using a vacuum printing frame,
It is preferable to provide a mat layer in order to prevent burning blur. Specifically, a method of providing a mat layer as described in JP-A-50-125805, JP-B-57-6582 and JP-B-61-28986 is disclosed.
A method of thermally fusing a solid powder as described in 2-62337 is exemplified.

Further, as described in claim 10, an overcoat layer made of a polymer having excellent oxygen barrier properties such as polyvinyl alcohol and acidic cellulose for the purpose of preventing oxygen inhibition of photopolymerization on the surface of the photosensitive layer. Can also be provided. The overcoat layer having the oxygen blocking effect is particularly effective when a photopolymerization photosensitive system is applied to the lipophilic photosensitive layer. As a coating method, a conventionally known method similar to that for coating the photosensitive layer is used.

[Matting Agent] The purpose of the matting layer is to improve the vacuum adhesion between the image film and the photosensitive lithographic printing plate in the contact exposure, thereby shortening the evacuation time and, furthermore, the fine mesh during exposure due to poor adhesion. It is to prevent the collapse of points. As a method for applying the mat layer, Japanese Patent Application Laid-Open
No. 12974, a method of heat-sealing powdered solid powder, a method of spraying and drying polymer-containing water described in JP-A-58-182636, and the like. It is desirable that the mat layer itself be dissolved in the alkali developer or removed by this.

[Coating] As described above, the present invention has a structure having a plurality of layers having different compositions. As a method of applying a plurality of layers, after applying and drying a hydrophilic photosensitive layer solution,
Examples include a method of continuously applying and drying the lipophilic photosensitive layer solution, and a method of applying the lipophilic photosensitive layer solution by a wet-on-wet method while the hydrophilic photosensitive layer solution is in a wet state. As a coating method, a conventionally known method, for example, spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating, curtain coating or the like is used. In addition, it is also preferable to adopt the simultaneous multilayer coating method. The thickness of the photosensitive layer is not particularly limited, but is preferably 5 to 30 mg / m ² in total thickness.

[Exposure] In the use of the photosensitive lithographic printing plate thus obtained, a conventionally used method can be applied. For example, a transparent original having a line image, a halftone dot image or the like is applied to the photosensitive surface. Exposure is performed in close contact, and then the photosensitive layer is removed from the non-image area using a suitable developer to obtain a relief image. Light sources suitable for exposure include mercury lamps, metal halide lamps, xenon lamps,
Chemical lamps, carbon arc lamps and the like are used.

[Treatment] The developer and development replenisher used in the development of the photosensitive lithographic printing plate of the present invention may contain an organic solvent, or may have a pH of 12 or more containing substantially no organic solvent. May be used.

First, a developing solution which does not substantially contain an organic solvent (solvent) will be described. A developer containing substantially no organic solvent means that the content of the organic solvent is 1% by weight or less.

The aqueous alkaline developer containing an alkali metal silicate is a solution containing an alkali metal silicate, for example, potassium silicate, sodium silicate, sodium metasilicate, potassium metasilicate and the like. Aqueous alkaline developers containing metal silicates include sodium hydroxide, potassium tribasic sodium phosphate,
Other alkaline agents such as dibasic sodium phosphate, sodium carbonate, potassium carbonate and the like can be contained. The concentration of the aqueous alkali solution at this time varies depending on the type of the photosensitive composition and the alkali, but is generally in the range of 0.1 to 10% by weight.

In the developing solution, [SiO ₂ ] / [M]
(Wherein [SiO ₂ ] represents the molar concentration of SiO ₂ ,
[M] indicates the molar concentration of the alkali metal) is 0.5 to
1.2 is preferred, and the SiO ₂ concentration is from 4 to
7% by weight is preferred. A nonionic surfactant may be added to the developing replenisher. The amount of nonionic surfactant added is
It is in the range of 0.01 to 10% by weight, preferably 0.0
It is in the range of 2 to 2% by weight. The developing replenisher may be composed of two or more liquids, but it is preferable that the developing replenisher be composed of one liquid because the supply section and the storage tank of the replenishing device become complicated and the apparatus becomes large. . PH of developer (2
5 ° C.) is preferably from 12 to 13.5, and the pH of the replenisher (25 ° C.) is preferably from 12.5 to 14, and the pH of the replenisher is higher than the pH of the developer by at least 0.5. Is preferred.

The developing replenisher may contain an alkali agent other than the alkali silicate. Such alkaline agents include potassium hydroxide, sodium hydroxide, lithium hydroxide, sodium phosphate tribasic, sodium phosphate dibasic, potassium phosphate tribasic, potassium phosphate dibasic, ammonium phosphate tribasic, Inorganic alkaline agents such as dibasic ammonium phosphate, sodium metasilicate, sodium bicarbonate, sodium carbonate, potassium carbonate, ammonium carbonate, etc .; organic alkaline agents such as mono, di or triethanolamine and tetraalkyl ammonium hydroxide; And organic ammonium silicate. The content of the alkali agent in the developer is preferably in the range of 0.05 to 20% by weight, and more preferably in the range of 0.1 to 10% by weight. The development replenisher was [SiO ₂ ] / [M] (where [SiO ₂ ] represents the molar concentration of SiO ₂ , and [M]
Is a molar concentration of the alkali metal) is 0.2 to 0.8, SiO ₂ concentration of 4 to 7% by weight relative to the total weight. Further, known additives can be added to the developing solution and the developing replenisher.

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

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

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

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

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

[Desensitizing Treatment] In the present invention, the exposed and developed photosensitive lithographic printing plate may be subjected to a desensitizing treatment. As the desensitizing agent, a hydrophilic organic polymer compound, a surfactant,
It can include acids, buffers, and organic solvents.

[0119]

EXAMPLES The present invention will be described more specifically with reference to the following examples. Example 1 (Preparation of support) An aluminum plate (material: 1050, tempered H16) having a thickness of 0.3 mm was degreased in a 5% by weight aqueous solution of caustic soda at 65 ° C. for 1 minute, and then washed with water.
In a 5 molar hydrochloric acid aqueous solution, 25 ° C., current density 60 A / dm
Electrolytic etching treatment was performed for 30 seconds under the condition ( ² ). Next, after a desmut treatment at 60 ° C. for 10 seconds in a 5% by weight aqueous sodium hydroxide solution, an anodizing treatment was performed for 1 minute at 20 ° C. and a current density of 3 A / dm ^{2 in} a 20% by weight aqueous sulfuric acid solution. . Further washing with water, followed by sealing treatment with a 1.5% aqueous solution of No. 3 sodium silicate at 80 ° C. for 20 seconds,
After washing with water, a support was prepared.

On the support prepared as described above, a photosensitive solution 1 having the following composition was applied so as to have a dry weight of 1.0 g / m ^2, and dried under an air stream at 85 ° C. for 2 minutes. A photosensitive liquid 2 having the following composition was also dried at 1.0 g.
/ M ^2, and dried under a stream of air at 85 ° C. for 2 minutes to prepare a photosensitive lithographic printing plate sample.

Photosensitive solution 1 (for hydrophilic photosensitive layer) Polyvinylpyrrolidone 5.5 g ECH-modified glycerol triacrylate (Denacol acrylate DA-314, manufactured by Nagase & Co., Ltd.) 3.0 g Thioxanthon containing quaternary ammonium salt (Kayacure QTX, 0.5g Triethanolamine 0.5g Condensation resin of diazodiphenylamine sulfate and formaldehyde 0.5g Water 100ml

Photosensitive solution 2 (for lipophilic photosensitive layer) HEMA / AN / MAA / EMA (40/25/5/30) copolymer (Mw 100,000) 5.3 g Dipentaerythritol hexaacrylate 3.0 g 2 , 4-Diethylthioxanthone 0.5 g 1- (4-methoxystyryl) -3,5-bis (trichloromethyl) -s-triazine 0.2 g 4- (N, N-dimethylamino) benzoic acid 0.3 g diazo Condensation resin of diphenylamine hexafluorophosphate and formaldehyde 0.5 g Blue dye (Victoria Pure Blue BOH, manufactured by Hodogaya Chemical Co., Ltd.) 0.2 g Fluorinated surfactant (Fluorard FC-430, manufactured by Sumitomo 3M) 0.03 g lactic acid Methyl 65 ml Propylene glycol monoethyl ether 25 ml Methyl ethyl ketone 1 0 ml

Comparative Example 1 The photosensitive solution 2 of Example 1 was applied on the support prepared as described above so that the dry weight was 2.0 g / m ² ,
The photosensitive lithographic printing plate sample was prepared by drying for 2 minutes under an air flow of the above.

Example 2 A photosensitive solution 3 having the following composition was applied on the support prepared as described above so that the dry weight was 1.0 g / m ² .
It was dried for 2 minutes in an air stream at 85 ° C., and was coated thereon with a photosensitive solution 4 having the following composition so as to have a dry weight of 1.0 g / m ^2, and dried for 2 minutes in an air stream at 85 ° C. A photosensitive lithographic printing plate sample was prepared.

Photosensitive solution 3 (for hydrophilic photosensitive layer) Polyvinylpyrrolidone 5.5 g ECH-modified glycerol triacrylate (Denacol acrylate DA-314, manufactured by Nagase & Co., Ltd.) 3.0 g Thioxanthon containing quaternary ammonium salt (Kayacure QTX, Nippon Kayaku Co., Ltd.) 0.5g Triethanolamine 0.5g Water 100ml

Photosensitive solution 4 (for lipophilic photosensitive layer) HEMA / AN / MAA / EMA (40/25/5/30) copolymer (Mw 100,000) 5.3 g Dipentaerythritol hexaacrylate 3.0 g 2 , 4-Diethylthioxanthone 0.5 g 1- (4-methoxystyryl) -3,5-bis (trichloromethyl) -s-triazine 0.2 g 4- (N, N-dimethylamino) benzoic acid 0.3 g blue Dye (Victoria Pure Blue BOH, manufactured by Hodogaya Chemical Co., Ltd.) 0.2 g Fluorinated surfactant (Fluorard FC-430, manufactured by Sumitomo 3M) 0.03 g Methyl lactate 65 ml Propylene glycol monoethyl ether 25 ml Methyl ethyl ketone 10 ml

Example 3 The photosensitive solution 3 was applied on the support prepared as described above so that the dry weight became 1.0 g / m ^2, and dried under a stream of air at 85 ° C. for 2 minutes. The photosensitive solution 4 was applied to the same dry weight of 1.0 g / m ² , dried under a stream of air at 85 ° C. for 2 minutes, and placed on an oxygen barrier layer solution (3% aqueous solution of polyvinyl alcohol in an interface). Activator added) to a dry weight of 0.5 g / m ² ,
The resultant was dried under an air stream at 85 ° C. for 2 minutes to prepare a photosensitive lithographic printing plate sample.

Comparative Example 2 The photosensitive solution 4 was applied on the support prepared as described above so that the dry weight was 2.0 g / m ^2, and dried under an air stream at 85 ° C. for 2 minutes. A lithographic printing plate sample was prepared.

Comparative Example 3 The photosensitive solution 4 was applied on the support prepared as described above so that the dry weight became 2.0 g / m ^2, and dried under a stream of air at 85 ° C. for 2 minutes. An oxygen barrier layer solution (a solution in which a surfactant is added to a 3% aqueous solution of polyvinyl alcohol) is applied thereto so that the dry weight becomes 0.5 g / m ² ,
The resultant was dried under an air stream at 85 ° C. for 2 minutes to prepare a photosensitive lithographic printing plate sample.

The dot area of each of the resulting photosensitive lithographic printing plate samples was measured according to the following evaluation method. Table 1 shows the results.

(Evaluation Method) The obtained sample was passed through a dot manuscript using a metal halide lamp at 40 mJ / cm.
Exposure No. ² was performed. Next, PS plate developer SD manufactured by Konica Corporation
After immersing in N-21 (4 times dilution) at 25 ° C for 60 seconds,
It was developed by rubbing with a sponge in running water. Using the obtained printing plate, printing was performed with a Heidelberg GTO printing machine. The dot area on the obtained paper was measured in terms of reflection density.

[0132]

[Table 1]

[0133]

According to the present invention, it is possible to provide a negative photosensitive lithographic printing plate capable of obtaining high image quality with suppressed dot gain and a method of manufacturing the same.

Claims (11)

[Claims] 1. A negative photosensitive lithographic printing plate having a plurality of layers having different compositions on a sheet-like support subjected to a hydrophilic treatment, wherein at least one of the plurality of layers is irradiated with actinic rays. Is a photosensitive layer that forms a hydrophilic layer by insolubilizing the developer, and any of the upper layers of the hydrophilic photosensitive layer is insolubilized in the developer by irradiation with actinic light, and becomes hydrophobic. A photosensitive lithographic printing plate comprising a photosensitive layer for forming a layer. 2. The method according to claim 1, wherein the hydrophilic photosensitive layer comprises (A) a photopolymerization initiator composition, (B) a compound having a polymerizable ethylenically unsaturated bond, (C) a polymer compound capable of forming a film,
2. The photosensitive lithographic printing plate according to claim 1, wherein the photosensitive lithographic printing plate comprises: 3. The photosensitive lithographic printing plate according to claim 2, wherein the polymer compound capable of forming a film (C) is a water-soluble polymer compound. 4. The polymer compound capable of forming a film (C) is a homopolymer of N-vinyl-2-pyridinone and / or a copolymer with another copolymerizable monomer. The photosensitive lithographic printing plate according to claim 3. 5. The photosensitive lithographic printing method according to claim 2, wherein the compound (B) having a polymerizable ethylenically unsaturated bond has an alcoholic hydroxyl group in a molecule. Edition. 6. The hydrophilic photosensitive layer has (A) a water-soluble or water-dispersible photopolymerization initiator composition, and (B) a water-soluble or water-dispersible polymerizable ethylenically unsaturated bond. The photosensitive lithographic printing plate according to claim 1, comprising a compound, (C) a polymer emulsion dispersible in an aqueous system, as a component. 7. The method according to claim 1, wherein the hydrophobic photosensitive layer comprises (a) a photopolymerization initiator composition, (b) a compound having a polymerizable ethylenically unsaturated bond, (c) a polymer compound capable of forming a film,
Is contained as a constituent component.
6. The photosensitive lithographic printing plate according to any of 6. 8. The hydrophobic photosensitive layer, wherein the hydrophobic photosensitive layer comprises (a) a photopolymerization initiator composition, (b) a compound having a polymerizable ethylenically unsaturated bond, and (c) a polymer dispersible in an organic solvent system. The photosensitive lithographic printing plate according to any one of claims 1 to 6, further comprising an emulsion. 9. The photosensitive lithographic printing plate according to claim 1, wherein the hydrophobic photosensitive layer contains a diazo compound as a constituent. 10. The photosensitive lithographic printing plate according to claim 1, wherein a layer for blocking oxygen is provided on the hydrophobic photosensitive layer. 11. A photosensitive layer which is insolubilized in a developing solution by irradiation with actinic light and forms a hydrophilic layer on a sheet-like support which has been subjected to a hydrophilizing treatment. A method for producing a negative photosensitive lithographic printing plate, comprising providing a photosensitive layer which is insoluble in a developing solution by irradiation with light and forms a hydrophobic layer.