JP2000330265A - Image forming material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a positive image forming material for IR laser for direct plate making which is excellent in chemical resistance and printing durability by forming a photosensitive layer containing an alkali soln.-soluble resin having urea bonds in the side chains and a compd. which absorbs light to generate heat on a supporting body. SOLUTION: A photosensitive layer containing an alkali soln.-soluble resin having urea bonds in the side chains and a compd. which absorbs light to generate heat is formed on a supporting body. In this image forming material, the photosensitive layer preferably further contains an alkali soln.-soluble resin having phenolic hydroxyl groups. In the alkali soln.-soluble resin, the urea bond group itself does not act as the alkali soln. soluble resin. The chemical resistance and strength of the resin after exposed are improved by the characteristics of the urea bond groups in the side chains introduced. Moreover, the urea bond groups do not inhibit solubility of the alkali soln. soluble resin with an alkali aq. soln. (developer).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming material which can be used as an offset printing master, and more particularly to a positive type image forming material for a so-called direct plate making infrared laser capable of making a plate directly from a digital signal of a computer or the like. About.

[0002]

2. Description of the Related Art In recent years, lasers have been remarkably developed. In particular, solid-state lasers and semiconductor lasers having a light-emitting region from the near-infrared ray to the infrared ray have been increasing in output and miniaturization. Therefore, these lasers are very useful as an exposure light source when making a plate directly from digital data of a computer or the like.

A positive lithographic printing plate material for an infrared laser, which uses an infrared laser having a light emitting region in the infrared region as an exposure light source, comprises a binder resin soluble in an aqueous alkali solution and an IR dye which absorbs light and generates heat. And the like. When the infrared laser is exposed to the infrared laser positive lithographic printing plate material, an IR dye or the like in the infrared laser positive lithographic printing plate material is mixed with the binder resin in a non-exposed area (image area). The interaction acts as a dissolution inhibitor that substantially reduces the solubility of the binder resin. On the other hand, in the exposed portion (non-image portion), the IR dye or the like absorbs light to generate heat, so that the interaction between the IR dye or the like and the binder resin is weakened. Therefore, at the time of development, the exposed portion (non-image portion) is dissolved in the alkaline developer to form a lithographic printing plate. However, in such a positive lithographic printing plate material for infrared laser, compared to a positive lithographic printing plate material made by UV exposure, a resin having high solubility in an alkali developing solution has to be used as a binder resin. Therefore, there is a problem that the chemical resistance during use is poor, and the use of a cleaner deteriorates the printing durability.

The above problem is caused by the following essential difference in the plate making mechanism between the positive lithographic printing plate material for infrared laser and the positive lithographic printing plate material made by UV exposure.

[0005] The positive type lithographic printing plate material to be made by UV exposure contains an alkaline aqueous solution-soluble binder resin and onium salts and quinonediazide compounds as essential components. Here, when the positive type lithographic printing plate material to be made by the UV exposure is exposed, the onium salt and the quinonediazide compound are exposed in the non-exposed area (image area) in the positive type lithographic printing plate material for infrared laser. Acts as a dissolution inhibitor in the same way as described above, but in exposed areas (non-image areas)
In, unlike the positive type lithographic printing material for infrared laser, decomposed by light to generate an acid,
It acts as a dissolution accelerator for the binder resin. Therefore, it is not necessary to use a resin having high solubility in an alkali developing solution in advance as a binder resin in a positive planographic printing plate material made by UV exposure.

On the other hand, in the positive lithographic printing plate material for infrared laser, the interaction between the IR dye or the like and the binder resin is weakened in the exposed portion (non-image portion) at the time of exposure, However, since it does not act as a dissolution accelerator for the binder, in order to increase the difference in solubility between the unexposed portion and the exposed portion, as described above, the binder resin must be dissolved in an alkali developer in advance. Therefore, it is necessary to use a resin having high properties.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and achieve the following objects. That is, an object of the present invention is to provide a positive image forming material for an infrared laser for direct plate making, which is excellent in chemical resistance and printing durability.

[0008]

Means for solving the above problems are as follows. That is, on the support,
An image forming material comprising: a photosensitive layer containing (A) a resin soluble in an aqueous alkaline solution having a urea bond in a side chain, and (B) a compound that absorbs light and generates heat.

In the image forming material, the photosensitive layer preferably further contains (C) a resin soluble in an aqueous alkali solution having a phenolic hydroxyl group.

(A) In an aqueous alkali solution-soluble resin having a urea bond in the side chain, the urea-bonding group itself does not act as an aqueous alkali solution-soluble group. In addition, due to the characteristics of the introduced urea binding group of the side chain, after exposure, chemical resistance,
Strength (hardness) is improved. Therefore, the solubility of the entire exposed portion (image portion) in the alkaline aqueous solution is reduced. On the other hand, the urea binding group does not inhibit the solubility of the resin (A) soluble in an aqueous alkaline solution in an aqueous alkaline solution (developer) during development. Therefore, it is presumed that (A) an image forming material using an aqueous alkali solution having a urea bond in the side chain is excellent in chemical resistance, and the printing durability is not reduced even by cleaning.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION -Photosensitive Layer- The photosensitive layer contains (A) a resin soluble in an aqueous alkali solution having a urea bond in a side chain, and (B) a compound which absorbs light and generates heat. .

[(A) Alkaline aqueous solution-soluble resin having urea bond in side chain] (A) Alkaline aqueous solution-soluble resin having urea bond in side chain (hereinafter referred to simply as “(A) Alkaline aqueous solution-soluble resin”) ) Is not particularly limited as long as it is a resin soluble in an aqueous alkali solution having a urea bond in a side chain, and a known resin can be used. In particular, from the viewpoint of chemical resistance when printing using a printing chemical, a vinyl polymer or polycondensation polymer having a structural unit represented by any of the following general formulas (a) to (c) A compound or a novolak resin having a urea bond in a side chain is particularly preferable. Further, it is preferable that a functional group which contributes to solubility in an aqueous alkali solution be present in the side chain in addition to the urea bond from the viewpoint of improving sensitivity.

[0013]

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In the above general formulas (a) to (c), R ₁
And R ₂ represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a carboxyl group, or a salt thereof. R
₃ represents a hydrogen atom, a halogen atom, an alkyl group or an aryl group. X represents a divalent linking group, such as an alkylene group or a phenylene group which may have a substituent. Y represents a divalent aromatic group which may have a substituent, for example, a phenylene group or a naphthylene group which may have a substituent.

The content of the structural unit represented by any one of the above general formulas (a) to (c) in the (A) alkali aqueous solution-soluble resin is 10 to 80 mol% in terms of charging ratio.
The copolymer is preferably contained, more preferably 15 to 70 mol%, particularly preferably 20 to 60 mol%. When the content is less than 10 mol%, the chemical resistance is poor, and when it exceeds 80 mol%, the solubility in an aqueous alkali solution is low and the sensitivity may be low.

The method for producing the polymer having the structural unit represented by any one of formulas (a) to (c) is not particularly limited, and it can be produced by various known methods. There is, for example, a method of polymerizing a polymerizable monomer in a solvent using a polymerization initiator.

In the method of polymerizing the polymerizable monomer in a solvent using a polymerization initiator, the polymerizable monomer may include one or more urea bonds in one molecule and one or more polymerizable monomers. And a monomer having an unsaturated bond such as a compound represented by the following general formula (d).

[0018]

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In the general formula (d), R represents a hydrogen atom or an alkyl group. X represents a divalent linking group, for example, an alkylene group or a phenylene group which may have a substituent. Y represents a divalent aromatic group which may have a substituent, and examples thereof include a phenylene group and a naphthylene group which may have a substituent.

Examples of the compound represented by the general formula (d) include 1- (N '-(4-hydroxyphenyl)
Ureido) methyl acrylate, 1- (N ′-(3-hydroxyphenyl) ureido) methyl acrylate, 1
-(N '-(2-hydroxyphenyl) ureido) methyl acrylate, 1- (N'-(3-hydroxy-4-
Methylphenyl) ureido) methyl acrylate, 1-
(N ′-(2-hydroxy-5-methylphenyl) ureido) methyl acrylate, 1- (N ′-(5-hydroxynaphthyl) ureido) methyl acrylate, 1-
(N ′-(2-hydroxy-5-phenylphenyl) ureido) methyl acrylate, 2- (N ′-(4-hydroxyphenyl) ureido) ethyl acrylate, 2-
(N ′-(3-hydroxyphenyl) ureido) ethyl acrylate, 2- (N ′-(2-hydroxyphenyl) ureido) ethyl acrylate, 2- (N ′-(3
-Hydroxy-4-methylphenyl) ureido) ethyl acrylate, 2- (N '-(2-hydroxy-5-methylphenyl) ureido) ethyl acrylate, 2-
(N '-(5-hydroxynaphthyl) ureido) ethyl acrylate, 2- (N'-(2-hydroxy-5-phenylphenyl) ureido) ethyl acrylate, 4-
(N ′-(4-hydroxyphenyl) ureido) butyl acrylate, 4- (N ′-(3-hydroxyphenyl) ureido) butyl acrylate, 4- (N ′-(2
-Hydroxyphenyl) ureido) butyl acrylate, 4- (N '-(3-hydroxy-4-methylphenyl) ureido) butyl acrylate, 4- (N'-(2
-Hydroxy-5-methylphenyl) ureido) butyl acrylate, 4- (N '-(5-hydroxynaphthyl) ureido) butyl acrylate, 4- (N'-(2
Acrylate derivatives such as -hydroxy-5-phenylphenyl) ureido) butyl acrylate: 1- (N '
-(4-hydroxyphenyl) ureido) methyl methacrylate, 1- (N ′-(3-hydroxyphenyl) ureido) methyl methacrylate, 1- (N ′-(2-hydroxyphenyl) ureido) methyl methacrylate,
1- (N '-(3-hydroxy-4-methylphenyl)
Ureido) methyl methacrylate, 1- (N ′-(2-
(Hydroxy-5-methylphenyl) ureido) methyl methacrylate, 1- (N ′-(5-hydroxynaphthyl) ureido) methyl methacrylate, 1- (N′-
(2-hydroxy-5-phenylphenyl) ureido)
Methyl methacrylate, 2- (N ′-(4-hydroxyphenyl) ureido) ethyl methacrylate, 2-
(N '-(3-hydroxyphenyl) ureido) ethyl methacrylate, 2- (N'-(2-hydroxyphenyl) ureido) ethyl methacrylate, 2- (N'-
(3-hydroxy-4-methylphenyl) ureido) ethyl methacrylate, 2- (N ′-(2-hydroxy-
5- (methylphenyl) ureido) ethyl methacrylate, 2- (N ′-(5-hydroxynaphthyl) ureido) ethyl methacrylate, 2- (N ′-(2-hydroxy-5-phenylphenyl) ureido) ethyl methacrylate, 4- (N ′-(4-hydroxyphenyl) ureido) butyl methacrylate, 4- (N ′-(3-hydroxyphenyl) ureido) butyl methacrylate,
4- (N '-(2-hydroxyphenyl) ureido) butyl methacrylate, 4- (N'-(3-hydroxy-
4- (methylphenyl) ureido) butyl methacrylate, 4- (N ′-(2-hydroxy-5-methylphenyl) ureido) butyl methacrylate, 4- (N′-
Examples thereof include methacrylate derivatives such as (5-hydroxynaphthyl) ureido) butyl methacrylate and 4- (N '-(2-hydroxy-5-phenylphenyl) ureido) butyl methacrylate. These may be used alone or in combination of two or more.

The polymerizable monomer has a characteristic absorption at 1600 to 1700 cm ⁻¹ in an infrared absorption spectrum based on a urea bond.
Can be identified. Further, identification by melting point, proton NMR or the like is also possible. For example, in the above specific example, 2-
(N ′-(4-hydroxyphenyl) ureido) ethyl methacrylate has a melting point of 131 to 133 ° C. and can be identified from absorption in an IR spectrum based on a hydroxyl group and the urea bond.

In addition to the compound represented by the general formula (d), for example, 2- (N '-(4-carboxylphenyl) ureido) ethyl acrylate, 2- (N'-
Such as (4-sulfamoylphenyl) ureido) ethyl acrylate, 2- (N ′-(4-sulfophenyl) ureido) ethyl acrylate, 2- (N ′-(4-phosphonophenyl) ureido) ethyl acrylate, etc. Acrylates having an acidic group: 2- (N ′-(4-carboxylphenyl) ureido) ethyl methacrylate;
2- (N '-(4-sulfamoylphenyl) ureido) ethyl methacrylate, 2- (N'-(4-sulfophenyl) ureido) ethyl methacrylate, 2-
Methacrylates having an acidic group such as (N ′-(4-phosphonophenyl) ureido) ethyl methacrylate: 2- (N′-methylureido) ethyl acrylate, 2- (N′-propylureido) ethyl acrylate, 2- (N'-phenylureido) ethyl acrylate, 2- (N '-(4-methylphenyl) ureido) ethyl acrylate, 2- (N'-(2-methylphenyl) ureido) ethyl acrylate, 2- (N '-Naphthylureido) ethyl acrylate, 2- (N'-(2
Acrylates having no acidic group, such as -phenylphenyl) ureido) ethyl acrylate;
(N′-methylureido) ethyl methacrylate, 2-
(N′-propylureido) ethyl methacrylate, 2
-(N'-phenylureido) ethyl methacrylate,
2- (N '-(4-methylphenyl) ureido) ethyl methacrylate, 2- (N'-(2-methylphenyl)
Ureido) ethyl methacrylate, 2- (N'-naphthylureido) ethyl methacrylate, 2- (N '-(2
Preferred are polymerizable monomers such as methacrylates having no acidic group such as -phenylphenyl) ureido) ethyl methacrylate.

In the above specific examples, 2- (N '-(4-carboxyphenyl) ureido) ethyl methacrylate is
It has a decomposition temperature of 220 ° C. and can be identified from the absorption of the IR spectrum based on the carboxyl group and the urea bond.

Regarding the method for producing the polymerizable monomer,
There is no particular limitation, and for example, a known production method in which an isocyanate compound represented by the following general formula (e) is reacted with an amine compound represented by the following general formula (f) is preferably used.

[0025]

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In the general formula (e), R represents a hydrogen atom or an alkyl group. X is the same as in the general formula (d). In the general formula (f), R ′ represents a hydrogen atom or an alkyl group which may have a substituent. Y is the same as in the general formula (d). Z represents a hydroxyl group, a carboxyl group, or a sulfonamide group.

In the above-mentioned production method, the above-mentioned general formula (e)
And Z in the general formula (f) is a hydroxyl group, R ′
Is a hydrogen atom, whereby a polymerizable monomer represented by the general formula (d) can be suitably obtained.

In the above production method, the amino group in the general formula (f) may be a hydroxyl group, a carboxyl group, or -N.
Since the activity to the isocyanate group is higher than that of the H-CO- group or the like, the polysynthetic monomer represented by the general formula (d) can be easily obtained. Also, if desired,
An excess of the amine compound represented by the general formula (f),
By gradually adding the isocyanate compound represented by the general formula (e) to this, the reaction can proceed more effectively.

The solvent is not particularly limited as long as it is a known organic solvent, and preferred is a solvent having no active hydrogen atom. Examples thereof include ethylene dichloride, cyclohexanone, methyl ethyl ketone, acetone, methanol, ethanol, and ethylene. Glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-methoxy-
2-propanol acetate, 1-methoxy-2-propyl acetate, 1-ethoxy-2-propyl acetate, dimethyl sulfoxide, toluene, ethyl acetate, methyl lactate, ethyl lactate, dioxane and the like. These may be used alone or in combination of two or more.

The reaction may be carried out until the isocyanate compound represented by the general formula (e) disappears or the amount of the urea bond becomes a constant amount, and is usually from 15 minutes to 24 hours. It is. Further, the reaction temperature is preferably 0 to 40 ° C.

The polymerizable monomer is optionally removed for the purpose of removing unreacted raw material components and by-products when reacted in an excess of the amine compound represented by the general formula (f). High purity can be obtained by neutralizing with an acidic compound such as dilute hydrochloric acid to convert the amine compound represented by the general formula (f) into a salt, followed by washing with water, filtration and vacuum drying.

The resin (A) soluble in an aqueous alkali solution is as follows:
A homopolymer of each polymerizable monomer containing a urea bond or 2
It may be a copolymer of at least one kind, but is preferably a copolymer with a compound having one or more polymerizable unsaturated bonds and containing no urea bond from the viewpoint of printing durability. .
The copolymer may have any structure such as a block, a random or a graft.

The copolymer is 100% by mole of the total amount of the polymerizable monomer and a compound having one or more polymerizable unsaturated bonds and not containing a urea bond. Those obtained by copolymerization using 10 to 80 mol% of a monomer are preferable.

Examples of the compound having one or more polymerizable unsaturated bonds and not containing a urea bond include, for example,
Methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, ethylhexyl acrylate, octyl acrylate, acrylic acid
t-octyl, chloroethyl acrylate, 2,2-dimethylhydroxypropyl acrylate, 5-hydroxypentyl acrylate, trimethylolpropane monoacrylate, pentaerythritol monoacrylate, glycidyl acrylate, benzyl acrylate,
Acrylates such as methoxybenzyl acrylate and tetrahydroacrylate: aryl acrylates such as phenyl acrylate and furfuryl acrylate: methyl methacrylate, ethyl methacrylate,
Propyl methacrylate, isopropyl methacrylate, amyl methacrylate hexyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, chlorobenzyl methacrylate, octyl methacrylate, 4-hydroxybutyl methacrylate, 5-hydroxypentyl methacrylate, 2,2-dimethyl-
Methacrylates such as 3-hydroxypropyl methacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, glycidyl methacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate: aryl methacrylates such as phenyl methacrylate, cresyl methacrylate, naphthyl methacrylate: Examples of acrylamide or a derivative thereof include N-methylacrylamide, N-ethylacrylamide, N-propylacrylamide, N-butylacrylamide, Nt-butylacrylamide, N-heptylacrylamide, N-octylacrylamide, N-cyclohexylacrylamide, and N-methylacrylamide. N-alkylacrylamides such as benzylacrylamide: N-arylacrylamides such as -phenylacrylamide, N-tolylacrylamide, N-nitrophenylacrylamide, N-naphthylacrylamide, N-hydroxyphenylacrylamide: N, N-dimethylacrylamide, N, N-diethylacrylamide, N, N -Dibutyl acrylamide,
N, N-dialkylacrylamides such as N, N-dibutylacrylamide, N, N-diisobutylacrylamide, N, N-diethylhexylacrylamide, N, N-dicyclohexylacrylamide: N-methyl-
N-phenylacrylamide, N-hydroxyethyl-
N, N-arylacrylamides such as N-methylacrylamide, N-2-acetamidoethyl-N-acetylacrylamide: N-methylmethacrylamide, N-ethylmethacrylamide, N-propylmethacrylamide as methacrylamide or derivatives thereof , N-
N-alkyl methacrylamides such as butyl methacrylamide, Nt-butyl methacrylamide, N-ethylhexyl methacrylamide, N-hydroxyethyl methacrylamide, N-cyclohexyl methacrylamide: N-phenyl methacrylamide, N-naphthyl methacryl N-aryl methacrylamides such as amides:
N, N-dialkyl methacrylamides such as N, N-diethyl methacrylamide, N, N-dipropyl methacrylamide, N, N-dibutyl methacrylamide:
N, N-diaryl methacrylamides such as N-diphenylmethacrylamide: N-hydroxyethyl-N-
Methacrylamide derivatives such as methyl methacrylamide, N-methyl-N-phenylmethacrylamide, N-ethyl-N-phenylmethacrylamide: allyl acetate, allyl caproate, allyl caprylate, allyl laurate, allyl palmitate, stearic acid Allyl compounds such as allyl, allyl benzoate, allyl acetoacetate, allyl lactate and allyloxyethanol: hexyl vinyl ether, octyl vinyl ether, dodecyl vinyl ether, ethylhexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, chloroethyl vinyl ether, 1-methyl- 2,2-dimethylpropyl vinyl ether, 2-ethylbutyl vinyl ether, hydroxyethyl vinyl ether, diethylene glycol vinyl ether Ter, dimethylaminoethyl vinyl ether, diethylaminoethyl vinyl ether, butylaminoethyl vinyl ether, benzyl vinyl ether, tetrahydrofurfuryl vinyl ether, vinyl phenyl ether, vinyl tolyl ether, vinyl chlorophenyl ether, vinyl 2,4-dichlorophenyl ether, vinyl naphthyl ether, vinyl Vinyl ethers such as anthranyl ether: vinyl butyrate, vinyl isobutyrate, vinyl trimethyl acetate, vinyl diethyl acetate, vinyl valate, vinyl caproate, vinyl chloroacetate, vinyl methoxy acetate, vinyl butoxy acetate, vinyl phenyl acetate, vinyl acetoate Acetate, vinyl lactate, vinyl-β-phenylbutyle And vinyl esters such as vinyl cyclohexylcarboxylate, vinyl benzoate, vinyl salicylate, vinyl chlorobenzoate, vinyl tetrachlorobenzoate and vinyl naphthoate: methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, Isopropyl styrene, butyl styrene, hexyl styrene, cyclohexyl styrene, dodecyl styrene, benzyl styrene, chloromethyl styrene, trifluoromethyl styrene, ethoxy methyl styrene, acetoxy methyl styrene, methoxy styrene, 4-methoxy-3-methyl styrene, dimethoxy styrene, Chlorostyrene, dichlorostyrene, trichlorostyrene, tetrachlorostyrene, pentachlorostyrene, bromostyrene, dibromo Styrene, iodostyrene, fluorostyrene, 2
Styrenes such as bromo-4-trifluoromethylstyrene and 4-fluoro-3-trifluoromethylstyrene: crotonates such as butyl crotonate, hexyl crotonate, crotonic acid and glycerin monocrotonate: dimethyl itaconate; Dialkyl itaconates such as diethyl itaconate and dibutyl itaconate: maleic acid or fumaric acid dialkyls such as dimethyl malate and dibutyl fumarate: maleimide, N-phenylmaleimide, N-2-methylphenylmaleimide, N-2 , 6-Diethylphenylmaleimide, N-2
Maleimides such as -chlorophenylmaleimide, N-cyclohexylmaleimide, N-laurylmaleimide and N-hydroxyphenylmaleimide; and N-vinylpyrrolidone, N-vinylpyridine, acrylonitrile, methacrylonitrile and the like. These compounds may be used alone or in combination of two or more.

Of these compounds, (meth) acrylates, (meth) acrylamides, maleimides, and (meth) acrylonitriles are particularly preferred.

In the present specification, the description referred to as (meth) acrylate means acrylate and methacrylate, and the description referred to as (meth) acrylic acid means acrylic acid and methacrylic acid. . Also,
The description of (meth) acrylonitrile means acrylonitrile and methacrylonitrile, and (meth) acrylamide means acrylamide and methacrylamide.

The molecular weight of the copolymer is preferably 2,000 or more in terms of weight average molecular weight, and
10,000 is more preferable. In addition, the number average molecular weight is 1000
The above is preferable, and 2000 to 400,000 is more preferable.

The photosensitive layer preferably further contains (C) a resin soluble in an aqueous alkali solution having a phenolic hydroxyl group (hereinafter sometimes referred to as “(C) a resin having a phenolic hydroxyl group”).

The mixing ratio of (C) the resin having a phenolic hydroxyl group to the resin (A) soluble in an aqueous alkali solution ((C) the resin having a phenolic hydroxyl group: (A) the aqueous resin soluble in an alkaline aqueous solution) is expressed as a weight ratio of 1 : 10
10 to 10: 1 is preferable, and 1: 5 to 5: 1 is more preferable. When the compounding ratio is less than the numerical range,
The interaction with the resin having a phenolic hydroxyl group is not sufficient, and the development latitude may be reduced.On the other hand, when the compounding ratio is beyond the above numerical range, the chemical resistance of the photosensitive layer becomes poor. Sometimes.

(C) Examples of the resin having a phenolic hydroxyl group include phenol formaldehyde resin and m
-Cresol formaldehyde resin, p-cresol formaldehyde resin, m- / p-mixed cresol formaldehyde resin, phenol / cresol (m-, p
Or a m- / p-mixture), and a novolak resin such as a mixed formaldehyde resin.

(C) The molecular weight of the resin having a phenolic hydroxyl group is from 500 to 2,000 in terms of weight average molecular weight.
The number average molecular weight is preferably 0 to 200 to 10,000.

Also, a condensate of phenol having an alkyl group having 3 to 8 carbon atoms as a substituent such as t-butylphenol formaldehyde resin or octylphenol formaldehyde resin described in US Pat. No. 4,123,279 is used. You may use together. These resins having a phenolic hydroxyl group may be used alone or in combination of two or more.

[(B) Compound that absorbs light to generate heat] (B) Compound that absorbs light to generate heat includes:
Various known pigments and dyes are preferably used. Examples of the pigment include commercially available pigments and color index (CI) handbook, "Latest Pigment Handbook" (edited by Japan Pigment Technical Association, published in 1977), "Latest Pigment Application Technology" (CMC
Publishing, 1986) and "Printing Ink Technology", CMC Publishing, 1984).

Examples of the pigments include black pigments, yellow pigments, orange pigments, brown pigments, red pigments, purple pigments, blue pigments, green pigments, fluorescent pigments, metal powder pigments, and polymer-bound pigments. . Specifically, insoluble azo pigments, azo lake pigments, condensed azo pigments, chelated azo pigments, phthalocyanine pigments, anthraquinone pigments, perylene and perinone pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, isoindolinone pigments And quinophthalone pigments, dyed lake pigments, azine pigments, nitroso pigments, nitro pigments, natural pigments, fluorescent pigments, inorganic pigments, carbon black and the like.

The pigment may be used without surface treatment, or may be used after surface treatment. Examples of the surface treatment include a method of surface-coating a resin or wax, a method of attaching a surfactant, and a method of bonding a reactive substance (for example, a silane coupling agent, an epoxy compound, or a polyisocyanate) to the pigment surface. Can be considered. The surface treatment method is described in “Properties and Applications of Metallic Soap” (Koshobo), “Printing Ink Technology” (CMC Publishing, 1984) and “Latest Pigment Application Technology” (CMC Publishing, 198).
6th edition).

The pigment has a particle size of 0.01 to 10
μm is preferable, and 0.05 to 1 μm is more preferable.
0.1-1 μm is particularly preferred. The particle size of the pigment,
If the thickness is less than 0.01 μm, the dispersion may not be preferable in terms of stability in the photosensitive layer coating solution.
If it exceeds μm, it is not preferable in terms of uniformity of the photosensitive layer.

As a method for dispersing the pigment, a known dispersion technique used in the production of ink or toner can be used. For the dispersion, an ultrasonic disperser, a sand mill, an attritor, a pearl mill, a super mill, a ball mill,
Impeller, desparser, KD mill, colloid mill,
A disperser such as a Dynatron, a three-roll mill, or a pressure kneader is used. For details, see “Latest Pigment Application Technology” (CM
C Publishing, 1986).

Examples of the dye include commercially available dyes and literatures (for example, "Dye Handbook" edited by The Society of Synthetic Organic Chemistry, Showa 45).
Known publications, for example, dyes such as azo dyes, metal complex salt azo dyes, pyrazolone azo dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinone imine dyes, methine dyes, and cyanine dyes. Can be Among the pigments and dyes, pigments and dyes that absorb infrared light or near infrared light are particularly preferable because they are suitable for use in lasers that emit infrared light or near infrared light.

As the pigment absorbing the infrared light or the near infrared light, carbon black is preferably used. Examples of the dye that absorbs infrared light or near infrared light include, for example, JP-A-58-125246 and JP-A-59-125246.
No. 84356, JP-A-59-202829, JP-A-Sho-6
0-78787, cyanine dyes described in JP-A-58-173696 and JP-A-58-181690.
Methine dyes described in JP-A-58-194595, JP-A-58-112793 and JP-A-58-112793.
No. 224793, JP-A-59-48187, JP-A-5-48187
Naphthoquinone dyes described in JP-A-9-73996, JP-A-60-52940 and JP-A-60-63744; squalilium dyes described in JP-A-58-112792; British Patent 434,875 And the like.

The dyes described in US Pat.
The near-infrared absorption sensitizers described in US Pat. No. 156,938 are also preferably used, and substituted arylbenzo (thio) pyrylium salts described in U.S. Pat. No. 3,881,924, JP-A-57-142645. (U.S. Pat. No. 4,327,169)
No. 3) described in JP-A-58-1983.
No. 181051, No. 58-220143, No. 59-4
Nos. 1363, 59-84248, 59-8424
No. 9, No. 59-146063, No. 59-146061
Pyrylium compounds described in JP-A-59-
No. 216146, US Pat.
Pentamethine thiopyrylium salt described in JP-A-83,475, pyrylium compounds disclosed in JP-B-5-13514 and JP-A-5-19702, and Epollight.
III-178, Epollight III-130, Epo
light III-125, Epollight V-176
A and the like are particularly preferably used.

Another particularly preferred example of the dye is a near-infrared absorbing dye described as formulas (I) and (II) in US Pat. No. 4,756,993. The amount of the pigment or dye added is preferably 0.01 to 50% by weight, more preferably 0.1 to 10% by weight, based on the total solid content of the printing plate material. In the case of the dye, 0.5 to 10% by weight is particularly preferable, and in the case of a pigment, 3.1 to 10% by weight is particularly preferable. When the amount of the pigment or dye is less than 0.01% by weight,
On the other hand, if the sensitivity is lowered, if it exceeds 50% by weight, the uniformity of the photosensitive layer may be lost and the durability of the recording layer may be deteriorated.

The dye or pigment may be added to the same layer as other components or to another layer. When added to a layer separate from other components, it is added to a layer adjacent to a layer containing a substance which is thermally decomposable and substantially reduces the solubility of the binder resin when not decomposed. Is preferred. The dye or pigment and the binder resin are preferably contained in the same layer, but may be contained in different layers.

[Other Components] The photosensitive layer may contain other components, if desired. Examples of the other components include various additives.Examples of such additives include thermally decomposable compounds such as onium salts, o-quinonediazide compounds, aromatic sulfone compounds, and aromatic sulfonate compounds. And a substance which substantially lowers the solubility of the resin (A) soluble in an aqueous alkali solution when not decomposed. The addition of the above-mentioned additive can improve the dissolution inhibiting property of the image area in the developer.

As the onium salt, a diazonium salt,
Examples thereof include ammonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenonium salts, arsonium salts and the like.

As the onium salt, for example, SI
Schlesinger, Photogr. Sci. Eng., 18, 387 (1974), T.
S. Bal et al, Polymer, 21, 423 (1980);
158230, diazonium salts described in U.S. Pat. Nos. 4,069,055 and 4,069,056, and ammonium salts described in the specification of JP-A-3-140140, DC Necker et al.
Macromolecules, 17, 2468 (1984), CS Wen et al, T
eh, Proc. Conf. Rad. Curing ASIA, p478 Tokyo, Oct
(1988), U.S. Patent Nos. 4,069,055 and 4,069,056, JV Crivello et al, Macromor
ecules, 10 (6), 1307 (1977), Chem. & Eng. News, Nov.
28, p31 (1988), EP 104,143, U.S. Patent 33
No. 9,049, No. 410,201, JP-A-2-150848, JP-A
Iodonium salt described in 2-296514, JV Crivello e
t al, Polymer J. 17, 73 (1985), JV Crivello et
al. J. Org. Chem., 43, 3055 (1978), WR Watt eta
l, J. Polymer Sci., Polymer Chem. Ed., 22, 1789 (1
984), JV Crivelloet al, Polymer Bull., 14, 279
(1985), JV Crivello et al, Macromorecules, 14
(5), 1141 (1981), JV Crivello et al, J. Polymer
Sci., PolymerChem.Ed., 17, 2877 (1979), European Patent Nos. 370,693, 233,567, 297,443, 297,
No. 442, U.S. Pat.Nos. 4,933,377, 3,902,114,
410,201, 339,049, 4,760,013, 4,734,4
No. 44, No. 2,833,827, German Patent No. 2,904,626,
The sulfonium salts described in 3,604,580 and 3,604,581, JV Crivello et al, Macromorecules, 10 (6), 1
307 (1977), JV Crivelloet al, J. Polymer Sci.,
Selenonium salts described in Polymer Chem. Ed., 17, 1047 (1979), CS Wen et al, Teh, Proc. Conf. Rad. C
Arsonium salts described in uring ASIA, p478 Tokyo, Oct (1988), and the like are preferably used. Among these, diazonium salts are particularly preferred, and as the diazonium salts,
Those described in JP-A-5-158230 are preferred.

The o-quinonediazide compound includes:
Compounds having various structures are preferred as long as they have at least one o-quinonediazide group and increase alkali solubility by thermal decomposition. Since the o-quinonediazide has both an effect of losing the ability to suppress the dissolution of the binder by thermal decomposition and an effect of changing o-quinonediazide itself to an alkali-soluble substance, the o-quinonediazide dissolves the binder. It can act as an accelerator.

The o-quinonediazide compound includes:
For example, J. "Light-Sensitive Systems", Coser (John Wiley & Sons. Inc.) 339-352
The compounds described on the page are mentioned, and in particular, sulfonic acid esters or sulfonic acid amides of o-quinonediazide reacted with various aromatic polyhydroxy compounds or aromatic amino compounds are preferable. Also, benzoquinone (1,2) -diazidosulfonic acid chloride or naphthoquinone- (1,1) described in JP-B-43-28403.
2) esters of -diazide-5-sulfonic acid chloride with pyrogallol-acetone resin, U.S. Pat. No. 3,046,12
Esters of benzoquinone- (1,2) -diazidesulfonic acid chloride or naphthoquinone- (1,2) -diazide-5-sulfonic acid chloride and phenol-formaldehyde resin described in No. 0 and 3,188,210. Preferred examples are given.

Further, esters of naphthoquinone- (1,2) -diazide-4-sulfonic acid chloride with phenol formaldehyde resin or cresol-formaldehyde resin, naphthoquinone- (1,2) -diazide-4-sulfonic acid chloride and pyrogallol Esters with acetone resins are likewise preferred. Other useful o-quinonediazide compounds are reported and known in numerous patents. For example, JP-A-47-5303,
JP-A-48-63802, JP-A-48-63803, JP-A-48-63802
No. 96575, JP-A-49-38701, JP-A-48-13354,
JP-B-41-11222, JP-B-45-9610, JP-B-49-17
No. 481, U.S. Pat.Nos. 2,797,213, 3,454,400,
No. 3,544,323, No. 3,573,917, No. 3,674,495
No. 3,785,825; British Patent No. 1,227,602;
Nos. 1,251,345, 1,267,005, 1,329,888,
No. 1,330,932, German Patent No. 854,890, and the like. These compounds may be used alone or in combination of two or more.

The amount of the o-quinonediazide compound to be added is preferably 1 to 50% by weight, more preferably 5 to 30% by weight, more preferably 10 to 30% by weight, based on the total solid content of the printing plate material.
% By weight is particularly preferred.

Examples of the counter ion of the onium salt include tetrafluoroboric acid, hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid, 5-nitro-o-toluenesulfonic acid, 5-sulfosalicylic acid, 2,5-dimethyl Benzenesulfonic acid, 2,4,6-trimethylbenzenesulfonic acid, 2-nitrobenzenesulfonic acid, 3-chlorobenzenesulfonic acid, 3-bromobenzenesulfonic acid, 2-fluorocaprylnaphthalenesulfonic acid, dodecylbenzenesulfonic acid, 1-naphthol -5-sulfonic acid, 2-
Methoxy-4-hydroxy-5-benzoyl-benzenesulfonic acid, p-toluenesulfonic acid and the like can be mentioned. Of these, particularly preferred are hexafluorophosphoric acid, alkylaromatic sulfonic acids such as triisopropylnaphthalenesulfonic acid and 2,5-dimethylbenzenesulfonic acid.

The amount of the additives other than the o-quinonediazide compound is preferably 1 to 50% by weight,
30% by weight is more preferable, and 10 to 30% by weight is particularly preferable. It is preferable that the additive and the binder are contained in the same layer.

For the purpose of further improving the sensitivity, a cyclic acid anhydride, phenols, and organic acids can be added. As the cyclic acid anhydride, U.S. Pat.
No. 8, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, 3,6-
Endoxy-Δ ⁴ -tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, maleic anhydride, chloromaleic anhydride, α-phenylmaleic anhydride, succinic anhydride, pyromellitic anhydride and the like. Examples of the phenols include bisphenol A, p-nitrophenol, p-ethoxyphenol, 2,4,4'-trihydroxybenzophenone, 2,3,4-trihydroxybenzophenone, 4-hydroxybenzophenone,
4 ', 4 "-trihydroxytriphenylmethane, 4,
4 ', 3 ", 4"-tetrahydroxy-3,5,3',
5'-tetramethyltriphenylmethane and the like. Examples of the mechanical acids include sulfonic acids, sulfinic acids, alkyl sulfates, and phosphonic acids described in JP-A-60-88942 and JP-A-2-96755.
There are phosphoric esters and carboxylic acids, and specifically, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, p-toluenesulfinic acid, ethyl sulfate, phenylphosphonic acid, phenylphosphinic acid, phenyl phosphate, phosphoric acid Diphenyl, benzoic acid, isophthalic acid, adipic acid, p-toluic acid, 3,4-dimethoxybenzoic acid, phthalic acid, terephthalic acid, 4-cyclohexene-
Examples thereof include 1,2-dicarboxylic acid, erucic acid, lauric acid, n-undecanoic acid, and ascorbic acid. The proportion of the cyclic acid anhydride, phenols or organic acids in the printing plate material is preferably 0.05 to 20% by weight, more preferably 0.1 to 15% by weight, and 0.1 to 10% by weight.
% By weight is particularly preferred.

The photosensitive layer may contain a surfactant, for example, a fluorine-based surfactant described in JP-A-62-170950, in order to improve coating properties. As the content of the surfactant, the content of the surfactant in the image forming material is set to 0.1.
It is preferably from 01 to 1% by weight, more preferably from 0.05 to 0.5% by weight.

The image-forming material of the present invention is formed by dissolving each of the above-mentioned components in a solvent and coating the solution on a support described later.

-Support-The support is preferably a dimensionally stable plate, for example, paper, paper laminated with plastic (for example, polyethylene, polypropylene, polystyrene, etc.), metal plate (for example, , Aluminum, zinc, copper, etc.), plastic films (eg, cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc.) ), Paper as described above, or paper or plastic film on which metal is laminated or vapor-deposited.

As the support, a polyester film or an aluminum plate is preferable, and among them, an aluminum plate which has good dimensional stability and is relatively inexpensive is particularly preferable. Suitable aluminum plates are a pure aluminum plate and an alloy plate containing aluminum as a main component and containing a trace amount of a different element, and may be a plastic film on which aluminum is laminated or vapor-deposited. The foreign elements contained in aluminum alloys include silicon, iron, manganese, copper,
Examples include magnesium, chromium, zinc, bismuth, nickel, and titanium. The content of the foreign element in the alloy is at most 10% by weight or less. As the aluminum plate, pure aluminum is preferable. However, since pure aluminum is difficult to produce due to refining technology, it may contain a slightly different element. As described above, the composition of the aluminum plate is not specified, and an aluminum plate of a conventionally known and used material can be appropriately used. The thickness of the aluminum plate is about 0.1 to 0.6 m
m is preferable, 0.15 to 0.4 mm is more preferable, and 0.2 to 0.3 mm is particularly preferable.

Prior to roughening the aluminum plate, if necessary, a degreasing treatment with a surfactant, an organic solvent, an alkaline aqueous solution or the like is performed to remove rolling oil on the surface. The surface roughening treatment of the surface of the aluminum plate is performed by various methods, for example, a method of mechanically roughening the surface, a method of electrochemically dissolving the surface, and a method of selectively dissolving the surface chemically. It is performed by the method of causing. As a mechanical method, a known method such as a ball polishing method, a brush polishing method, a blast polishing method, and a buff polishing method can be used. Further, as an electrochemical surface roughening method, there is a method of performing an alternating or direct current in a hydrochloric acid or nitric acid electrolyte. Further, as disclosed in JP-A-54-63902, a method in which both are combined can be used.

The aluminum plate thus roughened is
After an alkali etching treatment and a neutralization treatment as necessary, an anodic oxidation treatment is performed as required to increase the water retention and abrasion resistance of the surface. As the electrolyte used for the anodic oxidation treatment of the aluminum plate, various electrolytes for forming a porous oxide film can be used, and generally, sulfuric acid, phosphoric acid, oxalic acid, chromic acid or a mixed acid thereof is used. The concentration of these electrolytes is appropriately determined depending on the type of the electrolyte.

The conditions of the anodizing treatment vary depending on the electrolyte used, and thus cannot be specified unconditionally. In general, the concentration of the electrolyte is 1 to 80% by weight, and the solution temperature is 5%.
７０70 ° C., current density 5Ａ60 A / dm ² , voltage 1１〜
It is preferable that the electrolysis time is 100 seconds and the electrolysis time is 10 seconds to 5 minutes. The amount of the anodic oxide film by the anodic oxidation is 1.0
g / m ² or more is preferred. The amount of the anodized film is
When it is less than 1.0 g / m ² , the printing durability is insufficient, or when used as a lithographic printing plate, the non-image area is easily scratched, In some cases, so-called “scratch dirt” to which the toner adheres may easily occur.

After the anodic oxidation treatment, the surface of the aluminum is subjected to a hydrophilic treatment if necessary.
U.S. Pat.No. 2,714,066
Nos. 3,181,461, 3,280,734 and 3,902,
An alkali metal silicate (for example, sodium silicate aqueous solution) method as disclosed in US Pat. In this method, the support is immersed or electrolytically treated with an aqueous solution of sodium silicate. Also,
Methods for treating with potassium fluoride zirconate disclosed in U.S. Pat.No. 22063 and polyvinylphosphonic acid as disclosed in U.S. Pat.Nos. 3,276,868, 4,153,461 and 4,689,272. Can be

The solvent is not particularly limited and known solvents such as ethylene dichloride, cyclohexanone, methyl ethyl ketone, methanol, ethanol,
Propanol, ethylene glycol monomethyl ether, 1-methoxy-2-propanol, 2-methoxyethyl acetate, 1-methoxy-2-propyl acetate, dimethoxyethane, methyl lactate, ethyl lactate, N,
N-dimethylacetamide, N, N-dimethylformamide, tetramethylurea, N-methylpyrrolidone, dimethylsulfoxide, sulfolane, γ-butyrolactone, toluene and the like. These solvents may be used alone or as a mixture of two or more.

The concentration of each component (total solid content including additives) of the image forming material of the present invention in the solvent is preferably 1 to
50% by weight is preferred. The amount of coating (solid content) on the support obtained after coating and drying varies depending on the application,
When used for a photosensitive printing plate, generally, 0.5 to
5.0 g / m ² is preferred.

The coating method is not particularly limited, and includes known coating methods such as bar coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, blade coating, roll coating and the like. Can be As the amount of the coating decreases, the apparent sensitivity increases, but the film characteristics of the photosensitive layer deteriorate.

In the image forming material of the present invention, an undercoat layer can be provided between the support and the photosensitive layer, if desired. As the components of the undercoat layer, various organic compounds are used, and for example, phosphonic acids having an amino group such as carboxymethylcellulose, dextrin, gum arabic, and 2-aminoethylphosphonic acid, and may have a substituent. Phenylphosphonic acid, naphthylphosphonic acid, alkylphosphonic acid, glycerophosphonic acid, organic phosphonic acids such as methylenediphosphonic acid and ethylenediphosphonic acid, phenylphosphoric acid optionally having a substituent,
Organic phosphoric acids such as naphthylphosphoric acid, alkylphosphoric acid and glycerophosphoric acid, and optionally substituted phenylphosphinic acid, naphthylphosphinic acid, organic phosphinic acids such as alkylphosphinic acid and glycerophosphinic acid, glycine and β-alanine And the hydrochloride of an amine having a hydroxy group, such as the hydrochloride of triethanolamine. These may be used alone or in combination of two or more.

The undercoat layer can be provided by the following method. That is, water or methanol, ethanol, a method in which a solution obtained by dissolving the organic compound in an organic solvent such as methyl ethyl ketone or a mixed solvent thereof is coated on an aluminum plate, and provided by drying, water or methanol,
Ethanol, a solution in which the organic compound is dissolved in an organic solvent such as methyl ethyl ketone, or a mixed solvent thereof, is immersed in an aluminum plate to adsorb the compound,
After that, a method of washing and drying with water or the like and providing it is used.

In the former method, the concentration of the organic compound in the solution in which the organic compound is dissolved is 0.005
-10% by weight is preferred. In the latter method,
The concentration of the organic compound in the solution in which the organic compound is dissolved is preferably 0.01 to 20% by weight, and 0.05 to 5% by weight.
% By weight, and the temperature of the immersion is 20%.
To 90 ° C. is preferable, and 25 to 50 ° C. is more preferable. The immersion time is preferably 0.1 seconds to 20 minutes, and 2 seconds to
One minute is more preferred.

The solution in which the organic compound is dissolved contains a basic substance such as ammonia, triethylamine and potassium hydroxide and an acidic substance such as hydrochloric acid and phosphoric acid to adjust the pH to 1 to 12. Can also. Further, a yellow dye may be added for improving the tone reproducibility of the image forming material.

The coating amount of the organic undercoat layer is from 2 to 200
Preferably ^{mg / m 2, 5~100mg / m} 2 is more preferable. When the coating amount is out of the numerical range,
In some cases, sufficient printing durability may not be obtained.

The above-mentioned image forming materials include nonionic surfactants described in JP-A-62-251740 and JP-A-3-208514 in order to widen the stability of processing under development conditions. JP-A-59-121044, JP-A-4-13
An amphoteric surfactant as described in JP-A-149 can be contained.

Examples of the nonionic surfactant include sorbitan tristearate, sorbitan monopalmitate,
Sorbitan triolate, stearic acid monoglyceride, polyoxyethylene nonyl phenyl ether and the like can be mentioned. Examples of the surfactant include alkyldi (aminoethyl) glycine, alkylpolyaminoethylglycine hydrochloride, 2-alkyl-N-carboxyethyl-N-
Hydroxyethyl imidazolinium betaine and N-tetradecyl-N, N-betaine type (for example, trade name "Amogen K": manufactured by Dai-ichi Kogyo Co., Ltd.) and the like can be mentioned. The content of the nonionic surfactant and the amphoteric surfactant in the image forming material is 0.05 to 15% by weight.
Is preferable, and 0.1 to 5% by weight is more preferable.

Further, the image forming material may contain a printing-out agent for obtaining a visible image immediately after heating by exposure, and a dye or pigment as an image coloring agent. Representative examples of the printing-out agent include a combination of a compound that releases an acid upon exposure to light (photoacid releasing agent) and an organic dye that can form a salt. Specifically, a combination of o-naphthoquinonediazide-4-sulfonic acid halogenide and a salt-forming organic dye described in JP-A-50-36209 and JP-A-53-8128, −
36223, 54-74728, 60-3626, 61-1437
Combinations of trihalomethyl compounds and salt-forming organic dyes described in JP-A Nos. 48, 61-151644 and 63-58440 can be exemplified. Such trihalomethyl compounds include oxazole-based compounds and triazine-based compounds, both of which have excellent temporal stability and give clear print-out images.

As the colorant for the image, other dyes can be used in addition to the above-mentioned salt-forming organic dyes. Suitable dyes, including salt-forming organic dyes, include oil-soluble dyes and basic dyes. Specifically, Oil Yellow # 101, Oil Yellow # 103, Oil Pink # 312, Oil Green BG, Oil Blue BO
S, Oil Blue # 603, Oil Black BY, Oil Black BS, Oil Black T-505 (all manufactured by Orient Chemical Industries, Ltd.), Victoria Pure Blue,
Crystal violet (CI42555), methyl violet (CI42535), ethyl violet,
Rhodamine B (CI145170B), malachite green (CI42000), methylene blue (CI520
15) and the like. Also, JP-A-62-29
The dyes described in 3247 are particularly preferred. The content of these dyes is preferably from 0.01 to 10% by weight, and more preferably from 0.1 to 10% by weight, based on the total solid content of the image forming material.
3% by weight is more preferred. Further, a plasticizer is added to the image forming material, if necessary, in order to impart flexibility or the like to the photosensitive layer. For example, butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate,
An oligomer or polymer of trioctyl phosphate, tetrahydrofurfuryl oleate, acrylic acid or methacrylic acid, or the like is used.

The image forming material is usually subjected to image exposure and development processing. As a light source of the active light beam used for the image exposure, for example, a mercury lamp, a metal halide lamp,
Xenon lamps, chemical lamps, carbon arc lamps, and the like. Examples of the radiation include an electron beam, an X-ray, an ion beam, and a far-infrared ray. G-line, i-line, Deep-UV
Light, high-density energy beams (laser beams) are also used. Examples of the laser beam include a helium-neon laser, an argon laser, a krypton laser, a helium-cadmium laser, and a KrF excimer laser. In the present invention, a light source having an emission wavelength in the near infrared to infrared region is preferable, and a solid-state laser and a semiconductor laser are particularly preferable.

As a developing solution or a replenishing solution used in the developing treatment, a conventionally known aqueous alkali solution can be used. For example, sodium silicate, potassium, tribasic sodium, potassium, ammonium, dibasic sodium, potassium, ammonium, sodium carbonate, potassium, ammonium, sodium bicarbonate, potassium, potassium Ammonium, sodium borate, potassium, ammonium, sodium hydroxide,
And inorganic alkali salts such as ammonium, potassium and lithium. Also, monomethylamine,
Dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, ethyleneimine, ethylenediamine, Organic alkali agents such as pyridine are exemplified. One of these alkaline aqueous solutions may be used alone, or two or more thereof may be used in combination.

Among these alkaline aqueous solutions, aqueous silicate solutions such as sodium silicate and potassium silicate are particularly preferred. The reason is that the developability can be adjusted by the ratio and the concentration of the silicon oxide SiO ₂ and the alkali metal oxide M ₂ O which are the components of the silicate. And alkali metal silicates described in JP-B-57-7427.

When the development is carried out using an automatic developing machine, an aqueous solution (replenisher) having a higher alkali strength than the developer is added to the developer to replace the developer in the developing tank for a long time. A large amount of PS plates can be favorably processed without performing.

The developing solution and the replenishing solution may contain various surfactants or organic compounds as necessary for the purpose of promoting or suppressing the developing property, dispersing the developing residue, or enhancing the ink affinity of the printing plate image area. Solvents can be added. The surfactant is preferably an anionic, cationic, nonionic or amphoteric surfactant. Further, the developing solution and the replenisher may contain, if necessary, a reducing agent such as a sodium salt or a potassium salt of an inorganic acid such as hydroquinone, resorcin, sulfurous acid, and hydrogen sulfite; an organic carboxylic acid; an antifoaming agent; A softener or the like can be added.

The image-forming material developed using the above-mentioned developer and replenisher is post-treated with washing water, a rinsing solution containing a surfactant and the like, and a desensitizing solution containing gum arabic and a starch derivative. . As a post-process when the image forming material is used as a printing plate, these processes can be used in various combinations.

In recent years, in the plate making / printing industry, automatic developing machines for printing plates have been widely used in order to rationalize and standardize plate making operations. This automatic developing machine generally comprises a developing section and a post-processing section, and comprises a device for transporting a printing plate, each processing solution tank and a spray device, and while pumping the exposed printing plate horizontally, each pumped by a pump. The developing process is performed by spraying a processing liquid from a spray nozzle. Recently, a method has been known in which a printing plate is immersed and conveyed by a submerged guide roll or the like in a processing liquid tank filled with a processing liquid to perform processing. In such an automatic processing, the processing can be performed while replenishing each processing liquid with a replenisher according to the processing amount, the operating time, and the like. Further, a so-called disposable processing method in which processing is performed with a substantially unused processing liquid can also be applied.

The case where the image forming material is used as a photosensitive lithographic printing plate will be described. First, after the image forming material is exposed to light and developed, it is washed and / or rinsed and / or gummed, and an unnecessary image portion (for example, a film edge mark of an original film) of the obtained lithographic printing plate is obtained. If there is, the unnecessary image portion is erased. Such erasing is preferably carried out by applying an erasing liquid as described in, for example, Japanese Patent Publication No. 2-13293, to an unnecessary image portion, leaving it for a predetermined time, and then rinsing with water. A method described in JP-A-59-174842, in which active light guided by an optical fiber is applied to an unnecessary image portion and then developed, can also be used.

The lithographic printing plate obtained as described above can be subjected to a printing step after applying a desensitizing gum as required, but when it is desired to obtain a lithographic printing plate having higher printing durability. Is subjected to a burning process. When burning a lithographic printing plate, before burning,
No. 2518, No. 55-28062, JP-A No. 62-31859, No. 61-
It is preferable to treat with a surface-regulating liquid as described in each publication of 159655. As the method, a method of applying the printing solution on a lithographic printing plate with a sponge or absorbent cotton impregnated with the surface conditioning solution, or immersing the printing plate in a vat filled with the surface conditioning solution, Application by an automatic coater or the like is applied. Further, it is more preferable to make the application amount uniform with a squeegee or a squeegee roller after the application.

The coating amount of the surface conditioning liquid is generally 0.03 to 0.8.
g / m ² (dry weight) is preferred. The lithographic printing plate to which the surface conditioning liquid has been applied is dried if necessary, and then burned (for example, a burning processor sold by Fuji Photo Film Co., Ltd .: "BP-130").
0 "). The heating temperature and time in this case depend on the type of the component forming the image,
It is preferable to carry out at a temperature of 180 to 300 ° C. for about 1 to 20 minutes.

The burned lithographic printing plate can be subjected to conventional treatments such as washing with water and gumming if necessary. However, a surface conditioning solution containing a water-soluble polymer compound or the like can be used. When is used, so-called desensitizing treatment such as gumming can be omitted. The lithographic printing plate obtained by such a process is set on an offset printing machine or the like and used for printing a large number of sheets.

[0094]

Hereinafter, the present invention will be described with reference to Examples.
The scope of the present invention is not limited to these examples.

[(A) Synthesis of Alkaline Aqueous Solution-Soluble Resin] <Synthesis Example 1: Synthesis of (A) Alkaline Aqueous Solution-Soluble Resin 1>-Synthesis of Polymer Compound Containing Polymerizable Monomer-Methacryloyloxyethyl isocyanate 5g
And 15.0 g of 4-aminobenzoic acid were added to and dissolved in 150 g of dioxane solvent, and the mixture was stirred for 2 hours to give 2- (N ′-(4-carboxyphenyl) ureido) having the following structural unit. Ethyl methacrylate 28.0
g was obtained.

[0096]

Embedded image

-(A) Synthesis of Aqueous Solution of Alkaline Aqueous Solution- The obtained 2- (N '-(4-carboxyphenyl) ureido) ethyl methacrylate and N-phenylmaleimide (one or more polymerizable unsaturated bonds) And a compound having no urea bond) and a weight ratio (2- (N ′-(4
(Carboxyphenyl) ureido) ethyl methacrylate / N-phenylmaleimide) was polymerized at a ratio of 75/25 to obtain 20 g of (A) an aqueous alkaline solution-soluble resin 1 (weight average molecular weight (Mw) = 15,000).

<Synthesis Example 2: (A) Synthesis of Alkaline Aqueous Solution-Soluble Resin 2> In the synthesis of the polymer compound containing a polymerizable monomer of Synthesis Example 1, 15.5 g of methacryloyloxyethyl isocyanate was used and 4-amino Except that the phenol was 12.0 g and the dioxane solvent was 140 g, the same procedure as in Synthesis Example 1 was repeated except that
25.0 g of (N ′-(4-hydroxyphenyl) ureido) ethyl methacrylate was obtained.

[0099]

Embedded image

Next, in the synthesis of the aqueous alkaline solution-soluble resin 1 of Synthesis Example 1, the polymer compound containing a polymerizable monomer was 2- (N ′-(4-hydroxyphenyl) ureido) obtained above. Except for using ethyl methacrylate, in the same manner as in Synthesis Example 1, 20 g of (A) an alkali aqueous solution-soluble resin 2 (weight average molecular weight (Mw) = 16,000) was obtained.

<Synthesis Example 3: Synthesis of (A) Alkaline Aqueous Solution-Soluble Resin 3> In the synthesis of (A) alkali aqueous solution-soluble resin 1 of Synthesis Example 1, N-phenylmaleimide and methacrylamide were used as compounds containing no urea bond. And the weight ratio (2- (N ′-(4-carboxyphenyl))
(A) Alkaline aqueous solution-soluble resin 3 (weight average molecular weight (Mw)) except that ureido) ethyl methacrylate / N-phenylmaleimide / methacrylamide was polymerized at a ratio of 75/13/12. ) = 3
4,000) was obtained.

<Synthesis Example 4: Synthesis of (A) Alkaline Aqueous Solution-Soluble Resin 4> In the synthesis of (A) Alkaline Aqueous Solution-Soluble Resin 2 in Synthesis Example 2, methyl methacrylate and methacrylamide were used as compounds containing no urea bond. Use
Except that the weight ratio (2- (N ′-(4-carboxyphenyl) ureido) ethyl methacrylate / methyl methacrylate / methacrylamide) was polymerized in a ratio of 72/14/14, the same as in Synthesis Example 2, except that (A) Alkaline aqueous solution soluble resin 4 (weight average molecular weight (Mw) = 68,00
0) was obtained in an amount of 20 g.

<Synthesis Example 5: (A) Synthesis of Resin 5 Soluble in Aqueous Alkaline Solution> In the synthesis of (A) Resin 2 in Aqueous Solution Aqueous Solution of Synthesis Example 2, acrylonitrile and methacrylamide were used as compounds containing no urea bond. Except that the weight ratio (2- (N ′-(4-carboxyphenyl) ureido) ethyl methacrylate / methyl methacrylate / methacrylamide) was polymerized at a ratio of 65/20/15, the same as in Synthesis Example 1, except that (A) Alkaline aqueous solution-soluble resin 5 (weight average molecular weight (Mw) = 45,000)
Was obtained in an amount of 20 g.

<Synthesis Example 6: (A) Synthesis of resin 6 soluble in aqueous alkali solution> 11.9 g of phenyl isocyanate and 4-
12.0 g of aminophenol and dioxane solvent 120
g, and then dissolved for 2 hours.
22.0 g of (N′-phenylureido) phenol was obtained.

The obtained 4- (N'-phenylureido)
18.3 g of phenol and 2.4 of paraformaldehyde
Was dissolved in 100 g of oxalic acid, and the mixture was stirred and heated to 100 ° C. to give (A) an aqueous alkaline solution-soluble resin 6 (weight average molecular weight (Mw) = 2,000) represented by the following structural formula. ) Was obtained.

[0106]

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In the above structural formula, n is 1 to 15,
Ph in () is a benzene ring.

[Preparation of Support A] Al having a thickness of 0.3 mm
Wash the minium plate (material 1050) with trichlorethylene
After cleaning and degreasing, use a nylon brush and 400 mesh
Pumice-grain this surface with a water suspension and wash with water.
Washed well. This plate is made of 25% sodium hydroxide at 45 ° C.
Etch by dipping in an aqueous solution for 9 seconds.
Furthermore, it was immersed in 20% nitric acid for 20 seconds and washed with water. At this time
The amount of etching on the grained surface is about 3 g / m ^TwoMet.
Next, this plate was subjected to a current density of 15 A /
dm^Two3g / m^TwoAfter the DC anodic oxide coating of
And dried, and then the following undercoating liquid was applied,
It was dried at 0 ° C. for 1 minute to obtain a support A provided with an undercoat layer.
Was. The coating amount of the dried coating film is 10 mg / m^TwoMet.

-Undercoat liquid- 0.5 g of β-alanine 95 g of methanol 5 g of water

[Preparation of Support B] Al having a thickness of 0.3 mm
Wash the minium plate (material 1050) with trichlorethylene
After cleaning and degreasing, use a nylon brush and 400 mesh
Pumice-grain this surface with a water suspension and wash with water.
Washed well. This plate is made of 25% sodium hydroxide at 45 ° C.
Etch by dipping in an aqueous solution for 9 seconds.
Furthermore, it was immersed in 20% nitric acid for 20 seconds and washed with water. At this time
The amount of etching on the grained surface is about 3 g / m ^TwoMet.
Next, this plate was subjected to a current density of 15 A /
dm^Two3g / m^TwoAfter providing a direct current anodic oxide coating of
Treatment with 2.5% by weight aqueous solution of sodium at 30 ° C for 10 seconds
And apply the following undercoat liquid, and dry the coating film at 80 ° C for 15 seconds.
After drying, a support B provided with an undercoat layer was obtained. After drying
15 mg / m coating amount^TwoMet.

-Undercoat liquid--0.3 g of the following compound-100 g of methanol-1 g of water

[0112]

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(Example 1) A photosensitive solution containing the following components was applied to the obtained support A so as to have a coating amount of 1.3 g / m ² to obtain a lithographic printing plate.

-Photosensitive solution--Fluorine-containing polymer represented by the following structural formula 0.03 g-Soluble alkali aqueous solution (A) obtained in Synthesis Example 1 0.20 g Resin 1-m, p-cresol novolak (m, (p ratio = 6 / 0.80 g 4, weight average molecular weight = 3,500, unreacted cresol 0.5% by weight) ・ p-toluenesulfonic acid 0.003 g ・ tetrahydrophthalic anhydride 0.03 g ・ the following structural formula 0.017 g of a dye represented by the formula: 1-0.015 g of a counter ion of Victoria Pure Blue BOH as a naphthalenesulfonic acid anion; (Fluorinated surfactant) ・ γ-butyl lactone 10 g ・ methyl ethyl ketone 10 g ・ 1-methoxy-2-propanol 8 g

Fluorine-containing polymer

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Dye A

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-Evaluation of Printing Durability- The obtained lithographic printing plate was placed in an exposure unit (Trendsthethe).
r, manufactured by Creo Co., Ltd.) (laser power:
8.0 W, rotation speed: 140 rpm) and an automatic developing machine (L
P-900H, manufactured by FUJIFILM Corporation) and developer (L
H-DP (1: 7.8 dilution) at 30 ° C.
The development processing was performed for 2 seconds. Then, the lithographic printing plate is
Printing was performed with a printing machine (Heidel KOR-D machine). The printing was performed every 5000 sheets by wiping the lithographic printing plate with a cleaner (Plate Cleaner CL-1, manufactured by FUJIFILM Corporation). The printing durability at this time was evaluated based on the number of printed sheets. The printing durability was evaluated by visual observation, and evaluated based on the maximum number of printed sheets capable of maintaining the image quality at the beginning of printing. It can be said that the printing durability generally has no problem in practical use when it is about 50,000 sheets. The results are shown in Table 1.

Example 2 In Example 1, Synthesis Example 1
A lithographic printing plate was prepared in the same manner as in Example 1 except that the (A) aqueous alkali solution-soluble resin 2 obtained in Synthesis Example 2 was used instead of the (A) aqueous alkali solution-soluble resin 1 obtained in (1). The printing durability was evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Example 3) In Example 1, Synthesis Example 1
A lithographic printing plate was prepared in the same manner as in Example 1 except that the (A) aqueous alkali solution-soluble resin 3 obtained in Synthesis Example 3 was used instead of the (A) aqueous alkali solution-soluble resin 1 obtained in (1). The printing durability was evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Example 4) In Example 1, Synthesis Example 1
A lithographic printing plate was prepared in the same manner as in Example 1, except that the (A) aqueous alkali solution-soluble resin 4 obtained in Synthesis Example 4 was used instead of the (A) aqueous alkali solution-soluble resin 1 obtained in The printing durability was evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Example 5) In Example 1, Synthesis Example 1
In place of the dye A represented by the structural formula, the (A) aqueous alkali soluble resin 5 obtained in Synthesis Example 5 was used instead of the (A) aqueous alkali soluble resin 1 obtained in
Except for using Dye B represented by the following structural formula, a lithographic printing plate was prepared in the same manner as in Example 1, and the printing durability was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Dye B

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(Example 6) In Example 1, Synthesis Example 1
A lithographic printing plate was prepared in the same manner as in Example 1 except that the (A) aqueous alkali solution-soluble resin 6 obtained in Synthesis Example 6 was used instead of the (A) aqueous alkali solution-soluble resin 1 obtained in (1). The printing durability was evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Example 7) In Example 1, the support (A) provided with an undercoat layer was used in place of the support (A) provided with an undercoat layer, and the (A) alkaline aqueous solution obtained in Synthesis Example 1 was used. Instead of the soluble resin 1, the (A) aqueous alkali soluble resin 3 obtained in Synthesis Example 3 was used, and the dye B represented by the structural formula was used instead of the dye A represented by the structural formula. Except for the above, a lithographic printing plate was prepared in the same manner as in Example 1, and the printing durability was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 8 The procedure of Example 1 was repeated, except that the support B provided with an undercoat layer was used in place of the support A provided with an undercoat layer, and the (A) aqueous alkali solution obtained in Synthesis Example 1 was used. A lithographic printing plate was prepared in the same manner as in Example 1 except that the (A) aqueous alkali solution-soluble resin 6 obtained in Synthesis Example 6 was used instead of the soluble resin 1, The printing durability was evaluated. The results are shown in Table 1.

(Comparative Example 1) Synthesis Example 1 in Example 1
A lithographic printing plate was prepared in the same manner as in Example 1, except that 1.0 g of m, p-cresol novolak was used instead of 0.20 g of the alkali aqueous solution-soluble resin 1 obtained in Example 1. The printing durability was evaluated in the same manner as described above. The results are shown in Table 1.

(Comparative Example 2) In Example 1, a support B provided with an undercoat layer was used in place of the support A provided with an undercoat layer, and the alkaline aqueous solution-soluble resin 1 obtained in Synthesis Example 1 was used. A lithographic printing plate was prepared in the same manner as in Example 1, except that 1.0 g of m, p-cresol novolak was used instead of 0.20 g of
The printing durability was evaluated. The results are shown in Table 1.

[0128]

[Table 1]

Table 1 shows that the image-forming material of the present invention has excellent printing durability even when the cleaner is repeatedly used, and thus has excellent chemical resistance and printing durability.

[0130]

According to the present invention, it is possible to provide a positive type image forming material for an infrared laser for direct plate making which is excellent in chemical resistance and printing durability.

 ──────────────────────────────────────────────────続 き Continuing on the front page F-term (reference) 2H025 AA00 AA06 AA07 AA08 AA12 AC08 AD03 CB14 CB15 CB29 CB52 CC20 FA03 FA17 2H096 AA07 AA08 BA16 BA20 EA04 GA08 2H114 AA04 AA15 AA23 BA01 DA04 DA24 DA25 DA26 DA32 DA35 DA32 DA35 DA32 DA73 GA09 GA34

Claims (2)

[Claims] 1. A photosensitive layer comprising (A) a resin soluble in an aqueous alkali solution having a urea bond in a side chain and (B) a compound capable of absorbing light to generate heat on a support. An image forming material comprising: 2. The image forming material according to claim 1, wherein the photosensitive layer further contains (C) a resin soluble in an aqueous alkali solution having a phenolic hydroxyl group.