JPH11133592A - Image forming material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an image forming material capable of dealing with both negative and positive types, enhanced in sensitivity and storage stability and improved in handleability for users (handleable under white fluorescent lamps) by forming a responsive layer containing a specified acid generator on a substrate. SOLUTION: This image forming material is provided, on the substrate, with the responsive layer containing a dye sensitive to light in the wavelength region of 700-1200 nm and a compound having a bond decomposable with an acid and the acid generator not absorbing light in the wavelengths of >=400 nm and responsive to light in the wavelengths of <=400 nm. It is preferred that the acid generator is at least one selected from organic halogen compounds and diphenyliodonium salts, and the organic halogen compounds are s-triazine compounds, and the responsive layer contains a resin component insoluble in water but soluble in an aqueous solution of alkali.

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 provided with a sensitive layer having a so-called positive type photosensitive composition which is solubilized by heat or active light, or a so-called negative material which is insolubilized by heat or active light. The present invention relates to an image forming material provided with a sensitive layer having a photosensitive composition of a type, and more particularly to a technique capable of forming an image by exposure to infrared rays such as a semiconductor laser.

[0002]

2. Description of the Related Art Hitherto, a composition for a photosensitive lithographic printing plate having a positive photosensitive layer which is solubilized by actinic light has been known.

[0003] As a photosensitive material using a positive composition which is solubilized by irradiation with actinic light, an image forming material having a photosensitive layer containing an acid generator and an acid-decomposable compound is known. For example, U.S. Pat. No. 3,779,779 discloses a photosensitive composition containing a compound having an orthocarboxylic acid or a carboxylic amide acetal group.
JP-A-3-133429 discloses a photosensitive composition containing a compound having an acetal in the main chain.
No. 49 and JP-A-60-112446 disclose a composition containing a compound having a silyl ether group. These are all sensitive to ultraviolet light, and are alkali-solubilized by exposure to ultraviolet light to form non-image areas, and unexposed areas form image areas.

As a negative type, for example, Japanese Patent Publication No. 52-73
JP-A Nos. 64 and 52-3216 disclose photosensitive materials which form an image area by irradiating active light with photopolymerization or photocrosslinking by irradiation with active light, and use ultraviolet rays as the exposure means as in the positive type. . Further, U.S. Pat.
No. 99 includes an acid generator, an acid crosslinking material (resole resin),
A technique has been disclosed in which a photosensitive material containing a binder (novolak resin) and an infrared absorbent is exposed to infrared light to insolubilize exposed portions with alkali.

On the other hand, in recent years, there has been a demand for improved work efficiency. In response to the trend in the plate making industry, in order to easily perform conventional manual and time-consuming editing work by software using a computer, a plate making method that can be digitally recorded by an inexpensive and compact infrared semiconductor laser, that is, CTP (computer to plate) ) Is in the spotlight. This technology requires dyes that can absorb infrared laser light as an essential requirement,
The dye is contained in the photosensitive layer of the image-forming material, whereby an image can be formed by exposure to the above infrared semiconductor laser or the like.

[0006] These CTPs have a problem that sufficient sensitivity is not obtained as compared with the conventional case of exposure with actinic light (ultraviolet rays), storage stability is poor, and safelight properties are not sufficient. . Specifically, the phenomena often observed in the positive type are that the dot reproducibility fluctuates greatly due to sensitivity fluctuations, and that the negative type is liable to cause character stains. As a result, sufficient resistance cannot be obtained under a white fluorescent lamp, the sensitive layer in the image area is reduced during development in the positive type, and the printing durability is reduced. There is a need for a solution to these problems, such as the ease of occurrence.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to improve sensitivity, storage stability and user-friendliness (can be handled under a white fluorescent lamp. A) To provide an image forming material corresponding to a negative type and a positive type.

[0008]

The above object of the present invention has been attained by the following constitutions.

(1) 700 to 1200 nm on a support
An image-forming material comprising a dye-sensitive layer having the following wavelength, a compound having a bond decomposable by an acid, and a sensitive layer containing an acid generator having a wavelength of 400 nm or less.

(2) 700 to 1200 nm on a support
An image forming material comprising a sensitive layer containing a dye sensitive to the following wavelengths, a compound insoluble in alkali in the presence of an acid, and an acid generator sensitive to a wavelength of 400 nm or less.

In a preferred embodiment, the acid generator is at least one selected from an organic halogen compound and a diphenyliodonium salt; the organic halogen compound is an s-triazine compound; and the sensitive layer is water-insoluble. And an alkali water-soluble resin component.

That is, the present inventors have conducted intensive studies on the problem that the sensitivity and storage stability are poor in the exposure with CTP and the safelight property is insufficient. As a result, it is found that the cause is the acid generator. The present invention has been made based on the idea that, if the safelight property can be improved particularly by exposure in a bright room, good results will be obtained in both sensitivity and storage stability.

Hereinafter, the present invention will be described in detail.

[1] Sensitive Layer Composition (Acid Generator) The acid generator of the present invention has a wavelength of 400 nm.
An acid is generated by irradiation of the following actinic rays, and 400 n
A compound having no absorption band at a wavelength greater than m is used. Under this limitation, various known compounds and mixtures can be used. For example, BF ₄ ⁻ , PF ₆ ⁻ , Sb of diazonium, phosphonium, sulfonium, and iodonium
^{_{F 6 -, SiF 6 2-,}} ClO 4 - salt such as, JP-A-4-42
No. 158, an alkylonium salt, an organic halogen compound, an orthoquinone-diazidosulfonyl chloride, and an organometallic / organohalogen compound are also actinic ray-sensitive components that form or separate an acid upon irradiation with actinic light. It can be used as a photoacid generator in the invention.
An organic halogen compound known in principle as a free radical-forming photoinitiator is a compound that forms hydrohalic acid, and is used as a photoacid generator in the present invention unless it has an absorption band at 400 nm or more. be able to.

Examples of the compounds forming the above-mentioned hydrohalic acid include US Pat. Nos. 3,515,552, 3,536,489 and 3,779,778, and West German Patent Publication. No. 2,243,621, and compounds capable of generating an acid by photolysis described in, for example, West German Patent Publication No. 2,610,842 can also be used. Also, o-naphthoquinonediazide-4-sulfonic acid halogenide described in JP-A-50-36209,
No. 134410, an acid generator capable of forming an acid polymer by ultraviolet rays, for example, a compound having two oxysulfonyl groups and two oxycarbonyl groups, and an acid generator described in JP-A-4-19666. Specifically, tetrakis-
Aryl halides such as 1,2,4,5- (polyhalomethyl) benzene, tris (polyhalomethyl) benzene,
The polymer sulfonium salt containing silyl ether and the alkyl halide disclosed in JP-A-6-342209 are disclosed in JP-A-9-342209.
Oxime sulfonate compounds of JP-A-96900 and JP-A-6-67433, halogenated sulfolane derivatives of JP-A-4-338557, JP-A-6-236024, JP-A-6-214391, JP-A-6-214392,
Sulfonic esters of N-hydroxyimide compounds, diazo compounds or diazo resins described in JP-A-7-244378 can be used.

Hereinafter, specific examples of the acid generator used in the present invention will be shown.

[0017]

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[0018]

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[0019]

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[0020]

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In the present invention, an organic halogen compound and a diphenyliodonium salt are preferred from the viewpoint of sensitivity in image formation by infrared exposure and storage stability. As the organic halogen compound, s-triazines having a halogen-substituted alkyl group are particularly preferred. The maximum absorption wavelength λmax of the acid generator is preferably from 200 to 350 nm, and the molar extinction coefficient ε at λmax is preferably 10,000 or more, particularly preferably 20,000 or more.

The s-triazine acid generator is also disclosed in
44737, JP-A-9-90633, and JP-A-4
No. 226454 can be used.

In the present invention, the photoacid generator comprises the following 1
It is also preferable that any one of the above items 3 to 3 is satisfied.

1. 1. having an alkali-soluble site; 2. a bromomethylaryl ketone derivative; It is a trichloroacetylamino group-containing aromatic compound.

Examples of the compound having one alkali-soluble moiety include esters, compounds having two or more hydroxyl groups and alkyl sulfonic acids, compounds having two or more phenolic hydroxyl groups, and alkyl sulfones having a combination selected from the following: An anthracene derivative having two or more acids and hydroxyl groups and a sulfonic acid can be given.

Examples of the acid generator comprising an ester of a compound having two or more hydroxyl groups and an alkyl sulfonic acid include alcoholic hydroxyl groups such as ethylene glycol, propylene glycol, glycerin, and 1,2,4-butanetriol; Esters with acids are mentioned. The alkyl group of this alkyl sulfonic acid is CnH ₂
Those where n _{+ 1} and n = 1 to 4 are effective. It is also effective to substitute a part or all of the hydrogen in the alkyl group with a halogen having a high electronegativity such as fluorine or chlorine. The alkyl sulfonic acid ester used for the photoacid generator does not need to convert all the hydroxyl groups of the compound containing two or more alcoholic hydroxyl groups into esters, and the hydroxyl groups may be left. Thereby, the solubility in an alkaline aqueous solution can be controlled.

Examples of the photoacid generator comprising an ester of a compound having two or more phenolic hydroxyl groups and an alkylsulfonic acid include catechol, resorcin, hydroquinone, pyrogallol, oxyhydroquinone, phloroglucin, trihydrobenzophenone, tetrahydrobenzophenone, An ester of a phenolic hydroxyl group such as a gallic acid ester and an alkylsulfonic acid may be mentioned. The alkyl group of the alkylsulfonic acid is the same as described above. The alkyl sulfonic acid ester used for the photoacid generator does not need to convert all the hydroxyl groups of the compound containing two or more alcoholic hydroxyl groups into esters, and the hydroxyl groups may be left. Thereby, the solubility in an alkaline aqueous solution can be controlled.

Examples of the photoacid generator comprising an ester of an anthracene derivative having two or more hydroxyl groups and a sulfonic acid include esters of a hydroxyl group of a dihydroxyanthracene, trihydroxyanthracene and tetrahydroxyanthracene with a sulfonic acid. Examples of the sulfonic acid include alkylsulfonic acid, arylsulfonic acid, and 1,2-naphthoquinonediazidosulfonic acid. The alkyl of the alkyl sulfonic acid is the same as described above. The sulfonic acid ester used for the photoacid generator does not need to convert all of the hydroxyl groups of the compound containing two or more hydroxyl groups into esters, and the hydroxyl groups may be left. Thereby, the solubility in an alkaline aqueous solution can be controlled.

As the bromomethylarylketone derivative, bromomethylarylketone or dibromomethylarylketone is preferable. For example, 2-bromoacetylnaphthalene, 2-bromoacetyl-6,7-dimethoxynaphthalene, 2-bromoacetylnaphthalene, 2-dibromoacetyl-6,7-dimethoxynaphthalene, 1-
Hydroxy-4-bromo-2-bromoacetylnaphthalene, 1-hydroxy-4-bromo-2-dibromoacetylnaphthalene, 2-hydroxy-1-bromoacetylnaphthalene, 1,4-bis (bromoacetyl) benzene,
4,4'-bis (bromoacetyl) biphenyl, 1,
3,5-tris (bromoacetyl) benzene, 1,3
5-tris (dibromoacetyl) benzene and the like, and these can be used alone or in combination of two or more.

Further, as the aromatic compound having a trichloroacetylamino group, those having the following structure are more preferable.

[0031]

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In the formula, R _{1 to} R ₅ represent hydrogen, an alkyl or alkoxy group having 4 or less carbon atoms, a halogen atom, a phenylamino group, a phenoxy group, a benzyl group, a benzoyl group, an acetyl group, and a trichloroacetylamino group. , R _1-
R ₅ may be the same or different. Specifically, for example, 4-phenoxytrichloroacetanilide,
4-methoxytrichloroacetanilide, 2,3-dimethoxytrichloroacetanilide, 4-methoxy-2-
Chlorotrichloroacetanilide, 3-acetyltrichloroacetanilide, 4-phenyltrichloroacetanilide, 2,3,4-trifluorotrichloroacetanilide, 2,4,5-trimethyltrichloroacetanilide, 2,4,6-tribromotrichloroacetanilide, 2, 4,6-trimethyltrichloroacetanilide, 2,4-dichlorotrichloroacetanilide, 2,
4, -dimethoxytrichloroacetanilide, 2,5-
Dichlorotrichloroacetanilide, 2,5-dimethoxytrichloroacetanilide, 2,6-dimethyltrichloroacetanilide, 2-ethyltrichloroacetanilide, 2-fluorotrichloroacetanilide, 2-methyltrichloroacetanilide, 2-methyl-6-ethyltrichloroacetanilide, 2- Phenoxyacetanilide, 2-propyltrichloroacetanilide, 3,
4-dichlorotrichloroacetanilide, 3,4-dimethoxytrichloroacetanilide, 3,4-dimethyltrichloroacetanilide, 4-butylacetanilide,
4-ethylacetanilide, 4-fluoroacetanilide, 4-iodoacetanilide, 4-propylacetanilide, 2,3,4,5,6-pentafluoroacetanilide, 4-propoxyacetanilide, 4-acetylacetanilide and the like, In particular, they have high thermal stability and can be suitable photoacid generators.

In the present invention, the acid generator may be used alone or in combination of two or more. The content thereof can be varied widely depending on its chemical properties and the composition of the sensitive layer or its physical properties. The amount is suitably in the range of about 0.1 to about 20% by weight, and preferably in the range of 0.2 to 10% by weight, based on the total weight of the solid matter of the sensitive layer when the product is in a dry state or as an image forming material. It is.

(Acid-decomposable compound) The acid-decomposable compound of the present invention is disclosed in JP-A-48-89003 and 51-12.
Nos. 0714, 53-133429 and 55-129
No. 95, No. 55-126236, No. 56-17345
Compounds having a C--O--C bond described in JP-A-60-37549 and compounds having a Si--O--C bond described in JP-A-60-112446; And other acid-decomposable compounds described in JP-A Nos. 60-10247. Further, compounds having a Si--N bond described in JP-A-62-222246, and compounds disclosed in JP-A-62-1251743. And orthotitanate described in JP-A-62-280841, and JP-A-62-80841.
Orthosilicate described in JP-A-280842, acetal and ketal described in JP-A-63-10153, compounds having a CS bond described in JP-A-62-244038, 63 -231
No. 442, a compound having a -OC (= O)-bond or the like can be used. Of these, acetal and silyl ether are preferred.

The acid-decomposable compound used in the present invention includes:
Compounds that generate a diol compound containing an ethylene glycol component or a propylene glycol component after being decomposed by the action of an acid are preferred. Examples of such diol compounds of the general formula _{- (CH 2 -CH 2 -O)} n- or - (C
Those containing a component represented by H ₂ —CH ₂ (CH ₃ ) —O) m— are preferable. Here, n or m is preferably in the range of 1 to 5. The _{- (CH 2 -CH 2 -O)} n- (CH 2 -CH
₂ (CH ₃₎ -O) m- with those containing a copolymer component represented also preferred. Specific examples of these diol compounds include:
Ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, pentapropylene glycol, polypropylene glycol, poly-ethylene glycol-propylene glycol Polymers.

From the standpoint of sensitivity and development stability, ethylene glycol and diethylene glycol are particularly preferred. Further, an acetal or a silyl ether containing these diol components is particularly preferable, and a polycondensation compound represented by the general formula (1) is particularly preferable.

[0037]

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Here, n is an integer of 1 or more, and m is an integer including 0. X represents a carbon atom or a silicon atom, R ₄
Represents an ethyleneoxy group or a propyleneoxy group, and corresponds to a diol compound containing an ethylene glycol component or a propylene glycol component. R ₂ and R ₅ are hydrogen atoms,
R ₃ and R ₆ represent an alkyl group or an aryl group;
It represents an aryl group, and R ₂ and R ₃ or R ₅ and R ₆ may combine with each other to form a substituted or unsubstituted ring. R ₇ represents an alkylene group. R ₁ is a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an alkyleneoxy group, a halogen atom, and R ₈ is a hydrogen atom or —XR ₂ R ₃ R ₁ or —XR ₅
R ₆ R ₁ is shown.

Acetals are preferably synthesized from the condensation of the above-mentioned diol compounds with the dimethyl acetal or diethyl acetal of aldehydes and ketones from the viewpoint of yield. Examples of such aldehydes include acetaldehyde, chloral, ethoxyacetaldehyde, benzyloxyacetaldehyde, phenylacetaldehyde, diphenylacetaldehyde, phenoxyacetaldehyde, propionaldehyde, 2-phenyl and 3-phenylacetaldehyde.
-Phenylaldehyde, isobutoxybivalinaldehyde, benzyloxybivalinaldehyde, 3-ethoxypropanal, 3-cyano-propanal, n-butanal, isobutanal, 3-chloro-butanal, 3-chlorobutanal
Methoxy-butanal, 2,2-dimethyl-4-cyano-butanal, 2- and 3-ethylbutanal, n-pentanal, 2- and 3-methyl-pentanal, 2-
Bromo-3-methyl-pentanal, n-hexanal, cyclopentanecarbaldehyde, n-heptanal, cyclohexanecarbaldehyde, 1,2,3,6-
Tetrahydro-benzaldehyde, 3-ethylpentanal, 3- and 4-methyl-hexanal, n-octanal, 2- and 4-ethyl-hexanal, 3,5
5-trimethylhexanal, 4-methylheptanal, 3-ethyl-n-heptanal, decanal, dodecanal, crotonaldehyde, benzaldehyde, 2
-, 3- and 4-bromobenzaldehyde, 2,4- and 3,4-chloro-benzaldehyde, 4-methoxy-
Benzaldehyde, 2,3- and 2,4-dimethoxy-
Benzaldehyde, 2-, 3- and 4-fluoro-benzaldehyde, 2,3- and 4-methylbenzaldehyde, 4-isopropyl-benzaldehyde, 3- and 4
-Tetrafluoroethoxy-benzaldehyde, 1- and 2-naphthaldehyde, furfural, thiophene-
Examples thereof include 2-aldehyde, terephthalaldehyde, piperonal, 2-pyridinecarbaldehyde, p-hydroxy-benzaldehyde, 3,4-dihydroxy-benzaldehyde, 5-methyl-furaldehyde, vanillin and the like. As ketones, phenylacetone, 1,3
-Diphenylacetone, 2,2-diphenylacetone,
Chloro- and bromo-acetone, benzylacetone, methyl ethyl ketone, benzyl-propyl ketone, ethyl benzyl ketone, benzyl methyl ketone, isobutyl ketone, 5-methyl-hexane-2-one, 2-methyl-
Pentan-2-one, 2-methyl-pentan-3-one, hexane-2-one, pentan-3-one, 2-methyl-butan-3-one, 2,2-dimethyl-butane-
3-one, 5-methyl-heptane-3-one, octane-2-one, octane-3-one, octane-3-one, nonan-2-one, nonan-3-one, nonane-5
-One, heptane-2-one, heptane-3-one, heptane-4-one, undecane-2-one, undecane-4-one, undecane-5-one, undecane-6
On, dodecane-2-one, dodecane-3-one, tridecane-2-one, tridecane-3-one, tridecane-7-one, dinonyl ketone, dioctyl ketone, 2-
Methyl-octane-3-one, cyclopropyl methyl ketone, decane-2-one, decane-3-one, decane-
4-one, methyl-α-naphthyl-ketone, didecyl ketone, diheptyl ketone, dihexyl ketone, acetophenone, 4-methoxy-acetophenone, 4-chloro-
Acetophenone, 2,4-dimethyl-acetophenone,
2-, 3- and 4-fluoroacetophenone, 2-, 3
-And 4-methylacetophenone, 2-, 3- and 4-
Methoxyacetophenone, propiophenone, 4-methoxy-propiophenone, butyrophenone, valerophenone, benzophenone, 3,4-dihydroxybenzophenone, 2,5-dimethoxybenzophenone, 3,4-
Dimethoxybenzophenone, 3,4-dimethylbenzophenone, cyclohexanone, 2-phenyl-cyclohexanone, 2-, 3- and 4-methyl-cyclohexanone, 4-t-butyl-cyclohexanone, 2,6-dimethylcyclohexanone, 2-chlorocyclohexanone,
Cyclopentanone, cycloheptanone, cyclooctanone, cyclononanone, 2-cyclohexen-1one, cyclohexylpropanone, flavanone, cyclohexane-1,4-dione, cyclohexane-1,3-dionetropone, isophorone and the like.

Particularly preferred are aldehyde or ketone components having a solubility in water at 25 ° C. of 1 to 100 g / L. If the amount is less than 1 g / L, sludge is likely to be generated in the continuous processing, and if it is more than 100 g / L, the resolution of the formed image tends to decrease. Specific examples include benzaldehyde, 4-hydroxybenzaldehyde, 3,4-dihydroxybenzaldehyde, 2-pyridinecarbaldehyde, piperonal, phthalaldehyde, terephthalaldehyde, 5-methyl-2-phthalaldehyde, phenoxyacetaldehyde, phenylacetaldehyde, cyclohexanecarba Examples include aldehyde, vanillin, cyclohexanone, cyclohexen-1one, isobutyraldehyde, pentanal and the like. Of these, cyclohexanone is the most stable and preferred in continuous processing.

Silyl ethers are synthesized by condensation of a silyl compound with the diol compound. In the present invention, the silyl ethers preferably have a solubility in water of 1 to 100 g / L at 25 ° C. of a silyl compound formed by decomposition by the action of an acid.

Specific examples of the silyl compound include dichlorodimethylsilane, dichlorodiethylsilane, methylphenyldichlorosilane, diphenyldichlorosilane, and methylbenzyldichlorosilane.

The above-mentioned acetals and silyl ethers may be co-condensed with another alcohol component in addition to the diol compound. Specific examples of the alcohol component include methanol, ethanol, n-propanol, isopropanol, butanol, pentanol, hexanol,
Substituted or unsubstituted monoalkyl alcohols such as cyclohexanol and benzyl alcohol; glycols such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monophenyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monophenyl ether Examples include ether alcohols, substituted or unsubstituted polyethylene glycol alkyl ethers and polyethylene glycol phenyl ethers. Examples of the dihydric alcohol include pentane-1,5-diol, n-hexane-1,6-diol, and 2-ethylhexane-1,6-diol.
Diol, 2,3-dimethyl-hexane-1,6-diol, heptane-1,7-diol, cyclohexane-
1,4-diol, nonane-1,7-diol, nonane-1,9-diol, 3,6-dimethyl-nonane-1,
9-diol, decane-1,10-diol, dodecane-1,12-diol, 1,4-bis- (hydroxymethyl) -cyclohexane, 2-ethyl-1,4-bis-
(Hydroxymethyl) -cyclohexane, 2-methyl-
Cyclohexane-1,4-diethanol, 2-methyl-
Cyclohexane-1,4-dipropanol, thio-dipropylene glycol, 3-methylpentane-1,5-diol, dibutylene-glycol, 4,8-bis- (hydroxymethyl) -tricyclodecane, 2-butene-
1,4-diol, p-xylylene glycol, 2,5
-Dimethyl-hexane-3-yne-2,5-diol,
Bis- (2-hydroxyethyl) -sulfide, 2,
2,4,4, -tetramethylcyclobutane-1,3-diol and the like. In this embodiment, the molar ratio between the diol compound containing the ethylene glycol component or the propylene glycol component and the other alcohol component is 70/30.
To 100/0 is preferable, and 85/15 to 100/0 is more preferable.

The preferred molecular weight range of the acid-decomposable compound is as follows:
Kel permeation chromatography (GPC)
Weight average molecular weight M measured in terms of polystyrene
w is 500 to 10000, preferably 1000 to 300
0.

Examples of the acid-decomposable compound include JP-A-62-2.
No. 22246, compounds having a Si--N bond, carbonates described in JP-A-62-251743, orthotitanates described in JP-A-62-280841, 62-28084
Orthosilicate described in No. 2;
A compound having a CS bond described in JP-A-2-244038, and -OC (= O) in JP-A-63-231442.
A compound having a bond can be used in combination.

The synthesis examples of the acid-decomposable compound used in the present invention are shown below.

(Synthesis of Acid Decomposable Compound A-1)
While stirring 1.0 mol of dimethoxycyclohexane, 1.0 mol of diethylene glycol, 0.003 mol of p-toluenesulfonic acid hydrate and 500 ml of toluene, 1
The reaction was performed at 00 ° C. for 1 hour, and then the temperature was gradually increased to 150 ° C., and the reaction was further performed at 150 ° C. for 4 hours. Methanol generated by the reaction was distilled off during this period. After cooling, the reaction product was thoroughly washed with water, 1% aqueous NaOH,
Washed sequentially with 1N aqueous NaOH. After washing with brine and dehydration over anhydrous potassium carbonate, the mixture was concentrated under reduced pressure.
It was dried for 10 hours while heating to 80 ° C. under vacuum to obtain a wax-like compound. The weight average molecular weight Mw in terms of polystyrene measured by GPC was about 1200.

(Compound which can be insolubilized in alkali in the presence of acid) Compounds which can be insolubilized in alkali in the presence of acid (hereinafter referred to as acid insolubilizing agents) include those which are insolubilized in the presence of acid and soluble in alkali. And the like. The degree to which the solubility in alkali can be reduced may be such that the resin is changed to physical properties showing complete alkali insolubility by finally insolubilizing, such as crosslinking with an alkali-soluble resin. What was originally alkali-soluble by the action of the acid insolubilizing agent shows insolubility in an alkaline solution used as a developer and remains on the printing plate. Examples of the acid insolubilizing agent include a methylol group or a derivative of a methylol group, a melamine resin, a furan resin, an isocyanate, and a blocked-isocyanate (an isocyanate having a protective group), and a methylol group or an acetylated methylol group. Preferred are compounds and resole resins.

The acid insolubilizing agent further includes a silanol compound, a compound containing a carboxylic acid or a derivative thereof, a hydroxy group-containing compound, a compound having a cationically polymerizable double bond,
Secondary or tertiary alcohol having an aromatic group, an alkali-soluble polymer having an aromatic compound having a methylol group, an alkoxymethyl group or an acetoxymethyl group in a molecule, an aminoplast, a compound represented by the general formula (p), and a fat Cyclic alcohols and / or heterocyclic alcohols can be mentioned. Hereinafter, description will be made in order.

The silanol compound is a compound having one or more hydroxyl groups bonded to silicon atoms per silicon atom on average. Here the average is
For example, even if there is one silicon atom to which no hydroxyl group is bonded in the compound, the same effect can be obtained if there is one silicon atom to which two hydroxyl groups are bonded. Such silanol compounds include, for example, diphenylsilanediol, triphenylsilanol, cis- (1,3,5,7-tetrahydroxy)-
1,3,5,7-tetraphenylcyclotetrasiloxane and the like can be used.

The amount of the silanol compound is 5 to 70% by weight.
Is preferably within the range.

Examples of the compound containing a carboxylic acid or a carboxylic acid derivative include aromatic carboxylic acids such as cinnamic acid, benzoic acid, tolylacetic acid, toluic acid and isophthalic acid, and aromatic compounds such as dimethyl isophthalate and di-t-butyl isophthalate. And acid anhydrides such as aliphatic esters, glutaric anhydride, succinic anhydride, and benzoic anhydride; and copolymers such as styrene-maleic anhydride copolymer and styrene-methacrylic acid copolymer.

As the compound having a hydroxyl group,
Polyhydric alcohols such as glycerin, poly p-hydroxystyrene, p-hydroxystyrene / styrene copolymer,
High molecular compounds such as novolak resins are exemplified.

The compound having a carboxylic acid or a derivative thereof and the compound having a hydroxyl group are preferably used in combination, and the composition ratio is preferably in the range of 1:30 to 30 to 1 in terms of equivalent ratio. One of the compound having a hydroxyl group and the compound having a carboxylic acid or a derivative thereof may be a high molecular compound. When the compound having a hydroxyl group is a polymer compound, it is preferable to use a carboxylic acid or a derivative thereof in an amount of 1 to 50 in a weight ratio to the polymer compound 100. When the compound having a carboxylic acid or a derivative thereof is a polymer compound, it is preferable to use a compound having a hydroxyl group with respect to the polymer compound 100 in an amount of 1 to 20 in a weight ratio.

From the viewpoint of film-forming properties, it is preferable that at least one of the compound having a carboxylic acid or a derivative thereof and the compound having a hydroxyl group is a polymer compound. However, even if both are low molecular weight, it is sufficient that the coating film can be formed by a method such as mixing a high molecular compound. Preferred examples of the high molecular compound include alkali-soluble polymers.

A polymer compound having both a compound having a hydroxyl group and a carboxylic acid or a carboxylic acid derivative can be used. Examples of the polymer compound include p-hydroxystyrene having a hydroxyl group and a carboxylic acid or a carboxylic acid derivative, such as methacrylic acid ester such as methyl methacrylate, acrylic acid ester such as methyl acrylate, maleic anhydride, methacrylic acid, and acrylic acid. And the like.

The weight average molecular weight of these high molecular compounds is desirably in the range of 1,000 to 50,000. If the molecular weight is less than 1,000, sufficient heat resistance and coating properties cannot be obtained. On the other hand, when the molecular weight exceeds 50,000, the solubility in an aqueous alkali solution is not sufficient, and pattern deformation due to swelling is observed, so that high resolution cannot be obtained.

The amount of the compound having a carboxylic acid or a derivative thereof and the compound having a hydroxyl group are 5 to 5
It is preferably in the range of 0% by weight.

Compounds having a cationically polymerizable double bond include p-diisopropenylbenzene, m-diisopropenylbenzene, diphenylethylene, indenone,
Acenaphthene, 2-norbornene, 2,5-norbornadiene, 2,3-benzofuran, indole, 5-methoxyindole, 5-methoxy-2-methylindole, N-vinyl-2-pyrrolidone, N-vinylcarbazole At least one compound selected from the group can be mentioned. The amount of the compound having a cationic double bond is preferably in the range of 5 to 50% by weight.

Examples of the secondary or tertiary alcohol having an aromatic group include biphenyl derivatives, naphthalene derivatives and triphenyl derivatives, and are specifically represented by the following general formulas (a) to (d). Compounds.

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In the general formulas (a) to (d), R ₁ and R ₂ may be the same or different and each represents a hydrogen atom,
X represents a methyl group or an ethyl group, X represents a hydrogen atom, a halogen atom, a methyl group or a methoxy group, and Y represents -SO _{2
-, - CH 2 -, -} S -, - C (CH 3) 2 - represents, n
Represents 1 or 2.

As specific compounds, for example, 4,4 '
-Bis (α-hydroxyisopropyl) biphenyl,
3,3'-bis (α-hydroxyisopropyl) biphenyl, 2,4,2 ', 4'-tetra (α-hydroxyisopropyl) biphenyl, 3,5,3', 5'-tetra (α-hydroxyisopropyl) Biphenyl, 4,4 '
-Bis (α-hydroxyisopropyl) biphenyl sulfone, 3,3′-bis (α-hydroxyisopropyl)
Biphenyl sulfone, 4,4'-bis (α-hydroxyisopropyl) biphenylmethane, 3,3'-bis (α
-Hydroxyisopropyl) biphenylmethane, 4,
4'-bis (α-hydroxyisopropyl) biphenyl sulfide, 3,3'-bis (α-hydroxyisopropyl) biphenyl sulfide, 2,2-bis (4-α-
Hydroxyisopropylphenyl) propane, 2,2-
And bis (3-α-hydroxyisopropylphenyl) propane. The naphthalene derivative is 1,5-bis (1
-Hydroxypropyl) naphthalene, 2,6-bis (α
-Hydroxypropyl) naphthalene and the like. Triphenyl derivatives include tris (4-α-hydroxyisopropylphenyl) methane, tris (3-α-hydroxyisopropylphenyl) methane, 1,1,1-tris (4-
α-hydroxyisopropylphenyl) ethane, 1,
1,1-tris (3-α-hydroxyisopropylphenyl) ethane and the like.

The secondary or tertiary alcohol having an aromatic group may further include compounds represented by the following general formulas (e) to (g).

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In the general formula (e), R ₁ and R ₂ may be the same or different and each represents a hydrogen atom, a halogen atom or a methoxy group, and R ₃ represents a hydrogen atom, a phenyl group or a cyclopropyl group. . In the general formula (f), R
₄ and R ₅ may be the same or different and each represents a hydrogen atom or a phenyl group. In the general formula (g), A represents an alkyl group having 4 or less carbon atoms or a methylol group. Secondary or tertiary alcohols having a hydroxyl group at the carbon directly bonded to the aromatic ring include phenylmethanol derivatives, alicyclic alcohols having an aromatic ring, and the like.

The phenylmethanol derivatives include:
For example, diphenylmethanol, 4,4'-difluorodiphenylmethanol, 4,4'-dichloro-diphenylmethanol, 4,4'-dimethyl-diphenylmethanol, 4,4'-dimethoxydiphenylmethanol, triphenylmethanol, α- (4 -Pyridyl) -benzhydrol, benzylphenylmethanol, 1,1-diphenylethanol, cyclopropyldiphenylmethanol, 1-phenylethyl alcohol, 2-phenyl-2
-Propanol, 2-phenyl-2-butanol, 1-
Phenyl-1-butanol, 2-phenyl-3-butyn-2-ol, 1-phenyl-1-propanol, 1,
2-diphenylethylene glycol, tetraphenylethylene glycol, 2,3-diphenyl-2,3-butanediol, α-naphtholbenzein, α, α′-dihydroxy-p-diisopropylbenzene, α, α′-
Dihydroxy-m-diisopropylbenzene and the like.

Examples of the alicyclic alcohol having an aromatic ring include 1-indanol, 2-bromoindanol, chromanol, 9-fluorenol, and 9-hydroxy-3.
-Fluorene, 9-hydroxyxanthene, 1-acenaphthenol, 9-hydroxy-3-nitrofluorene,
Thiochroman-4-ol, 9-phenylxanthene-
9-ol, 1,5-dihydroxy-1,2,3,4-
Tetrahydronaphthalene, dibenzosuberenol, dibenzosuberol and the like can be mentioned.

Further, in addition to the above, 1- (9-anthryl) ethanol, 2,2,2
Examples thereof include 2-trifluoro-1- (9-anthryl) ethanol and 1-naphthylethanol.

As the alkali-soluble polymer having an aromatic ring having a methylol group, an alkoxymethyl group or an acetoxymethyl group in the molecule, one or two hydrogen atoms on the aromatic ring of the compound represented by the following general formula (h) can be used. Polymers having the excluded group in the molecule are exemplified.

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In the general formula (h), X represents a methylol group, an alkoxymethyl group having 1 to 5 carbon atoms or an acetoxymethyl group. Y represents an alkyl group, a hydroxyl group, a halogen atom, a hydrogen atom, or an alkoxy group.

As the alkali-soluble polymer, a polymer compound having a repeating unit represented by the following general formula (i) or (j) is preferable.

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In the general formulas (i) and (j), R ₁ represents an alkyl group, a hydrogen atom, a halogen atom or a cyano group, and L represents a single bond, —O—, —O—CO—, —CONR _{3
-, - CONR 3 CO -,} - CONR 3 SO 2 -, - NR 3
_{-, - NR 3 CO -,} - NR 3 SO 2 -, - SO 2 -, - S
O ₂ NR ₃ — or —SO ₂ NR ₃ CO— (R ₃ is a hydrogen atom,
Alkyl group, aralkyl group or aromatic ring group). X and Y have the same meanings as X and Y in formula (h).

The repeating unit represented by the above general formula (i) or (j) includes vinyl benzyl alcohol, α-methyl vinyl benzyl alcohol, vinyl benzyl acetate, α-methyl vinyl benzyl acetate, p-methoxy styrene, It is preferable to copolymerize with a monomer such as methylolphenyl methacrylamide.

As the aminoplast, a compound represented by the following general formula (k) is preferable.

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In the general formula (k), Z represents -NRR 'or a phenyl group. _{R, R ', R 10 ~R} 13 are each a hydrogen atom, -CH ₂ OH, -CH ₂ ORa or -CO-ORa
Represents Ra represents an alkyl group.

The melamine or benzoguanamine represented by the general formula (k) can be easily obtained as a commercial product, and their methylols can be obtained by condensation of melamine or benzoguanamine with formalin. Ethers can be obtained by modifying a methylol compound with various alcohols by a known method. As the alkyl group represented by Ra in the general formula (k), an alkyl group having 1 to 4 carbon atoms which may be linear or branched is preferable.

Specific examples of the compound represented by the general formula (k) include the following, but are not limited thereto.

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As aminoplast, the following general formula (1)
A melamine resin in which a plurality of triazine nuclei are bonded through a bond represented by the following general formula (m), and a compound represented by the following general formula (n) or (o). can do.

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In the general formulas (1) to (o), R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

The compound represented by the general formula (p) is as follows.

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In the formula, R represents a hydrogen atom, an alkyl group having 3 or less carbon atoms, an aryl group or a tolyl group, and R ₁ , R ₂ , R
₃ and R ₄ each represent a hydrogen atom, an alkyl group having 3 or less carbon atoms, or an alkoxy group having 3 or less carbon atoms.

As the compound represented by the general formula (p), o
-Acetylbenzoic acid, o-aldehydebenzoic acid, o-benzoylbenzoic acid, o-toluoylbenzoic acid, and o-acetoxybenzoic acid are preferably used. The content of the compound represented by formula (p) in the photosensitive layer is suitably in the range of 5 to 50% by weight, preferably 10 to 30% by weight.
It is.

As the alicyclic alcohol, for example, 2-
Adamantanol, 2-methyl-2-adamantanol, 2-ethyl-2-adamantanol, 2-propyl-2-adamantanol, 2-butyl-2-adamantanol, exo-norborneol, endo-norborneol, borneol , DL-isoborneol,
Terpinen-4-ol, S-cis-verbenol, isopinocanphenol, pinanediol and the like.

As the heterocyclic alcohol, for example, 1,
4-dioxane-2,3-diol, 5-methyl-1,
4-dioxane-2,3-diol, 5,6-dimethyl-1,4-dioxane-2,3-diol, DL-ex
o-Hydroxytropinone, 4-hydroxy-4-phenylpiperidine, 3-quinuclidinol, 4-chromanol, thiochroman-4-ol, DL-mavalonic acid lactone and the like. The heterocyclic alcohol preferably contains O or S in the heterocyclic ring.

The alcohols include alicyclic alcohols,
A secondary or tertiary alcohol may be further used in addition to the heterocyclic alcohol. The content of the alicyclic or heterocyclic alcohol is suitably from 5 to 50% by weight, and preferably from 10 to 30% by weight.

(Dye) As the dye, 700 to 1200
A substance sensitive to a wavelength of not more than nm is used, and it is preferable to use, for example, an infrared absorbing dye, carbon black, magnetic powder, or the like having an absorption at a wavelength of 700 nm or more. Particularly preferred infrared absorbing dyes are dyes having a maximum absorption at 700 to 1200 nm and a peak molar extinction coefficient ε of 10 ⁵ or more.

Examples of the infrared absorbing dye include cyanine dyes, squarium dyes, croconium dyes, azurenium dyes, phthalocyanine dyes, naphthalocyanine dyes, polymethine dyes, naphthoquinone dyes, thiopyrylium dyes, and dithiol metal dyes. Examples include complex dyes, anthraquinone dyes, indoaniline metal complex dyes, and intermolecular CT dyes. Examples of the infrared absorbing dye include JP-A-63-139191 and JP-A-64-33547.
No., JP-A-1-160683 and 1-280750
Nos. 1-293342, 2-2074, 3-
No. 26593, No. 3-30991, No. 3-34891
No. 3-36093, No. 3-36094, No. 3-
No. 36095, No. 3-42281, No. 3-10347
No. 6 and the like.

In the present invention, as the infrared absorbing dye, a cyanine dye represented by the following general formula (2) or (3) is particularly preferred.

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In the formula, Z ₁ and Z ₂ each represent a sulfur atom, a selenium atom or an oxygen atom, and X ₁ and X ₂ each form an optionally substituted benzo-fused ring or naphtho-fused ring. And R ₃ and R ₄ each represent a substituent, and one of R ₃ and R ₄ has an anionic dissociable group. R ₅ , R ₆ , R ₇ and R ₈ each represent an alkyl group having 1 to 3 carbon atoms, a hydrogen atom or a halogen atom. L represents a chain of conjugated bonds having 5 to 13 carbon atoms.

The cyanine dyes represented by formula (2) or (3) include those which form a cation and have a counter anion. In this case, the counter anion is C
_{^{l -, Br -, ClO 4}} -, BF 4 -, include alkylboron arsenide of t- butyl triphenyl borate arsenide.

In the general formula (2) or (3), the number of carbon atoms (n) in the conjugated bond chain represented by L is determined by using a laser emitting infrared light as a light source for image exposure. It is preferable to select an effective value according to the transmission wavelength of the light. For example, Y at an emission wavelength of 1060 nm
When an AG laser is used, n is preferably 9 to 13. The conjugate bond may have any substituent, and the conjugate bond may form a ring with a plurality of substituents. Further, the ring represented by X ₁ and the ring represented by X ₂ can have an arbitrary substituent. The halogen atom as a substituent, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, -SO ₃ M and -CO
A group selected from OM (M is a hydrogen atom or an alkali metal atom) is preferable. R ₃ and R ₄ are each an arbitrary substituent, preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms;-((CH ₂ ) n-
_{O-) k- (CH 2) mOR} (n and m are each an integer of 1 to 3, k is 0 or 1, R represents an alkyl group having 1 to 5 carbon atoms);. R ₃ and R ₄ One of —R—SO ₃ M and the other —R—SO ₃ ⁻ (R represents an alkyl group having 1 to 5 carbon atoms, M represents an alkali metal atom); or one of R ₃ and R ₄ represents —R On the other hand -COOM is -R-COO ^- (R is an alkyl group having 1 to 5 carbon atoms, M represents an alkali metal atom.) it is. R ₃ and R ₄ are, in terms of sensitivity and developability, R ₃ and one is above R ₄ -R-SO ₃ ^- or -R-C
OO ⁻ , and the other is preferably —R—SO ₃ M or —R-COOM.

When a semiconductor laser is used as a light source for image exposure, the infrared absorbing dye has a wavelength of 750 to 900 nm.
When an AG laser is used, those having an absorption peak at 900 to 1200 nm and having a molar absorption coefficient of ε> 1 × 10 ⁵ are preferable.

Further, one or more dyes belonging to both systems may be used in combination.

Typical examples of the infrared absorbing dye preferably used in the present invention are shown below, but it should not be construed that the invention is limited thereto.

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These dyes can be synthesized by known methods, but the following commercially available products can also be used.

Nippon Kayaku: IR750 (anthraquinone type); IR002, IR003 (aluminum type);
R820 (polymethine type); IRG022, IRG03
3 (diimmonium-based); CY-2, CY-4, CY-
9, CY-20, Mitsui Toatsu: KIR103, SIR10
3 (phthalocyanine); KIR101, SIR114
(Anthraquinone type); PA1001, PA1005
PA1006, SIR128 (metal complex type), Dainippon Ink & Chemicals: Fastogen blue 8120, Midori Kagaku: MIR-101, 1011, 1021 and the like. In addition, it is also commercially available from various companies such as Nippon Kogaku Dye, Sumitomo Chemical, Fuji Photo Film and the like.

In the present invention, the amount of the infrared absorbing dye added is preferably in the range of 0.5 to 10% by weight. If the amount exceeds 10% by weight, the developability of the non-image area (exposed area) decreases, and if it is less than 0.5% by weight, the sensitivity decreases.

The photosensitive layer composition of the present invention can significantly improve the printing durability when used as a lithographic printing plate by having a pigment. Examples of the pigment include known organic and inorganic pigments, and the pigments described in “Coloring Material Engineering Handbook” by Asakura Shoten and “Pigment Handbook” by Seibundo Shinkosha can be used without any particular limitation. Further, in order to obtain visible image after development, the pigment is preferably colored, and more preferably a high density is obtained. In that respect, it is preferable that the pigment is selected from phthalocyanine and carbon black not only to improve the printing durability but also to obtain a visible image after development.

(Dye 2) 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.
The term “change in color tone” includes any of 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 Mitsui Chemicals, Inc.), Crystal Violet, Brilliant Green, Ethyl Violet, Methyl Violet, Methyl Green, Erythrosin B, Paysic Fuchsin, Malachite Green, Oil Red, m-cresol Purple, rhodamine B, auramine, 4-p
Triphenylmethane-based, diphenylmethane-based, diphenylmethane-based, oxazine-based, xanthene-based, iminonaphthoquinone-based, azomethine-based or anthraquinone-based dyes represented by -diethylaminophenyliminonaphthoquinone, cyano-p-diethylaminophenylacetanilide, etc. Examples of the color changing agent that changes to the color tone of

On the other hand, examples of the color changing agent that 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 sensitive layer composition is preferably 0.01 to 10% by weight, more preferably 0.0 to 10% by weight.
2 to 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.

(Binder) The sensitive layer preferably contains a resin that is insoluble in water and soluble in an aqueous alkaline solution. Examples of such a resin include a novolak resin, a polymer having a hydroxystyrene unit, and a polymer containing an acrylate monomer component.

Examples of the novolak resin include phenol-formaldehyde resin, cresol-formaldehyde resin, phenol-cresol-formaldehyde copolycondensate resin described in JP-A-55-57841, and JP-A-55-57841. And a copolycondensate resin of p-substituted phenol and phenol or cresol and formaldehyde as described in JP 127553.

Examples of the polymer having a hydroxystyrene unit include polyhydroxystyrene and hydroxystyrene copolymer described in JP-B-52-41050.

Examples of the polymer containing an acrylic acid ester monomer component include a copolymer containing a substituted or unsubstituted alkyl acrylate and a substituted or unsubstituted alkyl methacrylate monomer component. As such monomer components, 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, methyl methacrylate, ethyl methacrylate, propyl methacrylate,
Butyl methacrylate, amyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate, methacryldecyl, undecyl methacrylate, undecyl methacrylate, dodecyl methacrylate, benzyl methacrylate, cyclohexyl methacrylate, methacrylate- 2-chloroethyl, N,
N-dimethylaminoethyl methacrylate, glycidyl methacrylate and the like can be mentioned.

The copolymer is preferably obtained by copolymerizing a mixture of the following monomers.

1) Monomers having an aromatic hydroxyl group, for example, 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 methacrylate, 5-hydroxypentyl acrylate, -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-aminophenyl acrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- (p-aminosulfonylphenyl) acrylamide and the like.

4) a monomer having a sulfonamide group,
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) Acrylamide or methacrylamides, for example, acrylamide, methacrylamide,
N-ethylacrylamide, N-hexylacrylamide, N-cyclohexylacrylamide, N-phenylacrylamide, N-nitrophenylacrylamide,
N-ethyl-N-phenylacrylamide, N- (4-
(Hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide and the like.

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

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

9) Vinyl esters, for example, vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl benzoate and the like.

10) Styrenes, for example, styrene, methylstyrene, chloromethylstyrene and the like.

11) Vinyl ketones, for example, methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, phenyl vinyl ketone and the like.

12) Olefins, for example, ethylene,
Propylene, isobutylene, butadiene, isoprene and the like.

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

14) Monomers having a cyano group, for example, acrylonitrile, methacrylonitrile, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethylacrylate, o-cyanostyrene, m-cyanostyrene, p-cyanostyrene 15) Monomers having an amino group, for example, N, N-diethylaminoethyl methacrylate, N, N-dimethylaminoethyl acrylate, N, N-dimethylaminoethyl methacrylate, polybutadiene urethane acrylate, N, N-dimethylaminopropyl acrylamide,
N, N-dimethylacrylamide, acryloylmorpholine, N-isopropylacrylamide, N, N-diethylacrylamide and the like.

The weight of the copolymer high molecular weight is preferably from 10,000 to 200,000 as measured by GPC, but the weight average molecular weight is not limited to this range.

The binder resins usable in combination with the above resins include polyester resins, polyvinyl acetal resins, polyurethane resins, polyamide resins, cellulose resins, olefin resins, vinyl chloride resins, styrene resins, polycarbonates, and the like. Examples include polyvinyl alcohol, polyvinyl pyrrolidone, polysulfone, polycaprolactone resin, polyacrylonitrile resin, urea resin, epoxy resin, phenoxy resin, and rubber-based resin. Further, a resin having an unsaturated bond in the resin, for example, diallyl phthalate resin and its derivative, chlorinated polypropylene and the like can be polymerized with the above-mentioned compound having an ethylenically unsaturated bond, so that it is suitably used depending on the application. be able to.

The content of these alkali-soluble resins in the sensitive layer is preferably in the range of 20 to 90% by weight, more preferably in the range of 30 to 70% by weight.

It is preferable to use a novolak resin in combination with a polymer having a hydroxystyrene unit or a polymer containing an acrylic acid ester monomer component.
The range of / 70 to 95/5 is preferred.

Further, a lipophilic resin can be added to the sensitive layer in order to improve the oil sensitivity of the composition. Examples of the lipophilic resin include, for example, JP-A-50-1258.
No. 06, a condensate of a phenol substituted with an alkyl group having 3 to 15 carbon atoms and an aldehyde, for example, a t-butylphenol formaldehyde resin can be used.

It is also preferable to add a self-oxidizing compound such as nitrocellulose or metal powder, or an ultraviolet absorber to the sensitive layer.

[2] Method for Producing Image Forming Material The image forming material used in the present invention is dissolved in the following solvent that dissolves the above-mentioned components, and these are coated on a suitable support surface and dried. It is obtained by providing a sensitive layer.

Examples of the solvent include propylene glycol monomethyl ether, propylene glycol monoethyl ether, methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve, ethyl cellosolve acetate, dimethylformamide, dimethyl sulfoxide, dioxane, acetone, cyclohexanone, trichloroethylene, methyl ethyl ketone, lactic acid Examples include methyl, ethyl lactate, and dimethylacetamide. These solvents can be used alone or in combination of two or more.

The pH of the coating solution is adjusted to 3.5 to 8.
0 or less, more preferably 4.0 or more and 6.5 or less.
If the value is 3.5 or less, the above effect cannot be expected.

As such a pH adjuster, a basic compound is preferably added. The basic compound is a compound capable of capturing protons, and specifically includes inorganic or organic ammonium salts, organic amines, amides, urea and thiourea and derivatives thereof, thiazoles, pyrroles, pyrimidines, and piperazine. , Guanidines, indoles, imidazoles, imidazolines, triazoles, morpholines, piperidines, amidines, formazines, pyridines, Schiff bases, salts of weak acids with sodium or potassium, JP-A-8-123030 No. 9-54437, an organic basic compound described in JP-A-9-54437, a thiosulfonate compound described in JP-A-8-212598, and a heat-neutralized basic compound described in JP-A-7-219217 ( Sulfonyl hydrazide compound). When a heat-neutralized basic compound is used, the sensitivity is greatly improved by heating after exposure and before development. Specific examples are described below.

As the amine compound, ammonium acetate,
Methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, n-
Propylamine, di-n-propylamine, tri-n-
Propylamine, isopropylamine, sec-butylamine, tert-butylamine, cyclohexylamine, benzylamine, tricyclohexylamine, tribenzylamine, octadecylbenzylamine, stearylamine, α-phenylethylamine, β-phenylethylamine, ethylenediamine, tetramethylenediamine , Hexamethylenediamine, tetramethylammonium hydroxide, aniline, methylaniline, dimethylaniline, diphenylaniline, triphenylaniline, o
-Toluidine, m-toluidine, p-toluidine, o-
Anisidine, m-anisidine, p-anisidine, o-chloroaniline, m-chloroaniline, p-chloroaniline, o-bromoaniline, m-bromoaniline, p-bromoaniline, o-nitroaniline, m-nitroaniline, p-nitroaniline, 2,4-dinitroaniline,
2,4,6-trinitroaniline, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, benzidine, p-aminobenzoic acid, sulfanilic acid, sulfanilamide, pyridine, 4-dimethylaminopyridine, piperidine, piperazine 2-benzylimidazole, 4-phenylimidazole, 2-phenyl-4-methyl-imidazole, 2-undecyl-imidazoline, 2,4,5-trifuryl-2-imidazoline,
1,2-diphenyl-4,4-dimethyl-2-imidazoline, 2-phenyl-2-imidazoline, 1,2,3-
Triphenylguanidine, 1,2-ditolylguanidine, 1,2-dicyclohexylguanidine, 1,2,3
-Tricyclohexylguanidine, guanidine trichloroacetate, N, N'-dibenzylpiperazine, 4,4 '
-Dithiomorpholine, morpholinium trichloroacetic acid,
Examples include 2-amino-benzothiazole, 2-benzoylhydrazino-benzotoazole, allyl urea, thiourea, methyl thiourea, allyl thiourea, ethylene thiourea and the like.

Specific compounds of the Schiff base include compounds having at least one structure represented by the following general formula (4) in the molecule.

[0156]

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Provided that R ₁ and R ₂ are a hydrocarbon group (for example, an alkyl group such as methyl group, isopropyl group, octyl group, heptadecyl group, cycloalkyl group such as cyclobutyl group and cyclohexyl group, phenyl group, tolyl group, etc.). An aryl group, etc.) and R ₃ represent a hydrogen atom or a hydrocarbon group (the same groups as mentioned for R ₁ and R ₂ ).

The compound having the above structure can be synthesized by condensation of an aldehyde or ketone with an amine.

More specifically, a condensation reaction of a polyvalent amine with a monovalent aldehyde or monovalent ketone, a monovalent amine with a polyvalent aldehyde or polyvalent ketone,
It can be synthesized by a polycondensation reaction between a divalent amine and a divalent aldehyde or a divalent ketone.

Examples of monovalent amines include methylamine, propylamine, n-butylamine, n-amylamine, n-heptylamine, n-octylamine and n-octylamine.
Nanonylamine, n-decylamine, n-dodecylamine, n-tridecylamine, 1-tetradecylamine,
n-pentadecylamine, 1-hexadecylamine, n
-Heptadecylamine, 1-methylbutylamine, octadecylamine, isopropylamine, tert-butylamine, sec-butylamine, tert-amylamine, isoamylamine, 1,3-dimethylbutylamine, 3,3-dimethylbutylamine, tert-octylamine, 1,2-dimethylbutylamine, 4-methylpentylamine, 1,2,2-trimethylpropylamine, 1,3-dimethylpentylamine, cyclobutylamine, cyclopentylamine, cyclohexanemethylamine, cyclohexylamine, aniline, o-toluidine, m-Toluidine, p-toluidine, m-ethylaniline, p-ethylaniline, p-butylaniline and the like. Examples of divalent amines include methine diamine, ethylene diamine, 1,3-diaminopropane,
1,2-diaminopropane, 1,2-diamino-2-methylpropane, 2,5-dimethyl-2,5-hexanediamine, 1,4-diaminobutane, 1,5-diaminopentane, 1,4-hexane Diamine, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 4,
4'-methylenebiscyclohexaneamine, 1,2-diaminocyclohexane, 1,3-cyclohexanebismethylamine, benzidine, 4-aminophenyl ether, o-tolidine, 3,3'-dimethoxybenzidine,
o-phenylenediamine, 4-methoxy-o-phenylenediamine, 2,6-diaminotoluene, m-phenylenediamine, p-phenylenediamine, 2,3-diaminonaphthalene, 1,5-diaminonaphthalene, 1,8-
And diaminonaphthalene. Examples of monovalent aldehydes include formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, 2-methylbutyraldehyde,
Ethyl butyraldehyde, valeraldehyde, isovaleraldehyde, hexanal, 2-ethylhexanal,
2,3-dimethylvaleraldehyde, octylaldehyde, cyclohexanecarboxaldehyde, cyclooctanecarboxaldehyde, phenylacetaldehyde, 2-phenylpropionaldehyde, diphenylacetaldehyde, benzaldehyde, o-tolualdehyde, m-tolualdehyde, p-tolualdehyde, o -Anisaldehyde, m-anisaldehyde, p-anisaldehyde, o-ethoxybenzaldehyde, p-ethoxybenzaldehyde, 2,4-dimethylbenzaldehyde, 2,5-dimethylbenzaldehyde, 4-biphenylcarboxaldehyde, 2-naphthaldehyde, etc. Examples of divalent aldehydes include o-phthalic dicarboxaldehyde, isophthalaldehyde,
Terephthaldicarboxaldehyde and the like. Further, examples of monovalent ketones include acetone, 2-butanone, 2-pentanone, 3-pentanone, 3-methyl-
2-pentanone, 2-hexanone, 3-hexanone, 3
-Methylhexanone, 2-heptanone, 3-heptanone, 3-methylheptanone, 2-octanone, 3-octanone, 2-nonanone, cyclobutanone, cyclopentanone, phenylacetone, benzylacetone, 1-phenyl-2- Butanone, 1,1-diphenylacetone,
Examples include 1,3-diphenylacetone, 2-phenylcyclohexanone, 2-ylidene, β-tetralone, propiophenone, o-methylacetophenone, and benzophenone. Examples of divalent ketones include 2,4-pentane Dione, 2,3-hexanedione, 2,5-hexanedione, 2,7-octanedione, 2,3-butadione, 2-methyl-1,3-cyclopentadione, 1,3
-Cyclohexanedione, 1,4-cyclohexadione, 1,3-cyclopentanedione, 3-acetyl-2
-Heptanone, 2,2,6,6-tetramethyl-3,5
-Heptadione, 2-methyl-1,3-cyclohexanedione, 5,5-dimethyl-1,3-cyclohexanedione, dibenzoylmethane, 1,4-dibenzoylbutane, p-diacetylbenzene, m-diacetylbenzene, Benzyl, 4,4'dimethoxybenzyl, 2-phenyl-1,3-indandione, 1,3-indandione, o-dibenzoylbenzene, 1,2-naphthoquinone, 1,4-naphthoquinone and the like.

The following are specific examples of Schiff bases.

[0162]

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The basic compound can be used without any particular limitation in addition to the compounds described above as long as it can capture protons.

These basic compounds may be used alone or in combination of two or more. The amount used is 0.0
It is preferably from 0.01 to 10% by weight, more preferably from 0.01 to 5% by weight. When the content is 0.001% by weight or less, there is no effect of improving the storage stability and suppressing a decrease in reproducibility of small spots with time after exposure, and when the content is 10% by weight or more, the sensitivity is significantly reduced.

In the measurement, a photosensitive layer coating solution was prepared by dissolving a solid content of 10% by weight in an arbitrary organic solvent, water or a plurality of mixed solvents used for coating, and used as a measuring device by Toa Denpa Kogyo Co., Ltd. ) Digital pH meter HM-3
After the pH meter was standardized as a measurement condition using 0S, the measurement part of the pH meter was lowered vertically to the coating solution to be measured, and the measured value when immersed in the coating solution for 2 minutes was defined as the pH of the coating solution. .

As a support, aluminum, zinc,
Metal plates such as steel, copper, etc., and metal plates, paper, plastic films and glass plates plated or deposited with chromium, zinc, copper, nickel, aluminum, iron, etc., paper coated with resin, metal foil such as aluminum Paper, hydrophilically treated plastic film, and the like. Of these, an aluminum plate is preferred. When the present invention is applied to a photosensitive lithographic printing plate, it is preferable to use, as a support, an aluminum plate which has been subjected to surface treatment such as graining treatment, anodic oxidation treatment and, if necessary, sealing treatment. These processes are described in JP-A-53-67507.
No. 53-77702, No. 53-123204,
Nos. 54-63902, 54-92804, 54
-133903, 55-128494, 56-
No. 28893, No. 56-51388, No. 58-424
No. 93, No. 58-209597, No. 58-19709
No. 0, No. 59-182967, No. 60-190392
No. 62-160291 and No. 61-182950
No. 63-99992, JP-A-1-150583
No. 1-154797, No. 1-176594, No. 1-188699, No. 1-188395, No. 1-2
Nos. 15591, 1-2242289, 1-2494
No. 94, No. 1-304893, No. 2-16090,
2-81692, 2-107490, 2-1
No. 85493, No. 3-104694, No. 3-1775
No. 28, No. 4-176690, No. 5-24376,
Nos. 5-24377, 5-139067, 6-2
A known method such as that described in Japanese Patent No. 47070 can be applied.

Examples of the graining method include a mechanical method and an electrolytic etching method.
Examples of the mechanical method include a ball polishing method, a brush polishing method, a polishing method using liquid honing, and a buff polishing method. The various methods described above can be used alone or in combination depending on the composition of the aluminum material and the like.

For etching by electrolysis, phosphoric acid,
It is carried out using a bath in which inorganic acids such as sulfuric acid, hydrochloric acid and nitric acid are used alone or in combination of two or more. After the graining treatment, if necessary, a desmut treatment is performed with an aqueous solution of an alkali or an acid to neutralize and wash with water.

The anodic oxidation treatment is carried out by using a solution containing one or more of sulfuric acid, chromic acid, oxalic acid, phosphoric acid, malonic acid or the like as an electrolytic solution, and using an aluminum plate as an anode for electrolysis. The amount of anodic oxide film formed is 1 to 50 m
g / dm ² is suitable, and preferably 10 to 40 mg / g.
dm ² , particularly preferably 25 to 40 mg / dm ² . The amount of the anodic oxide film can be determined, for example, by immersing the aluminum plate in a chromic acid phosphate bath solution (prepared by dissolving 35 g of phosphoric acid 85% solution and 20 g of chromium (IV) oxide in 1 liter of water), It is determined by measuring the change in weight before and after dissolution of the coating on the plate.

Examples of the sealing treatment include boiling water treatment, steam treatment, sodium silicate treatment, and dichromate aqueous solution treatment. In addition, the aluminum plate support may be subjected to an undercoating treatment with an aqueous solution of a water-soluble polymer compound or a metal salt such as fluorinated zirconic acid.

On the back surface of the support, a coating layer made of a metal oxide obtained by hydrolysis and polycondensation of an organic metal compound or an inorganic metal compound or an organic polymer is used in order to suppress the elution of the anodic oxide film of aluminum. It is preferable to provide a coating layer made of a compound (hereinafter, referred to as a back coat layer).

The back coat layer may be used in such an amount that the elution of aluminum is suppressed during development, and is preferably in the range of 0.001 to 10 g / m ² , more preferably 0.01 to 1 g / m 2. ² or less, 0.02
It is most preferably at least 0.1 g / m ² .

As a method for coating the back coat layer on the back surface of the aluminum support, various methods can be applied.
The most preferable method for securing the above-mentioned coating amount is a method of preparing a coating liquid for the back coat layer, coating and drying.

As the method for applying the sensitive layer to the surface of the support, conventionally known methods such as spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating, curtain coating and the like are possible. is there. Although the amount of application varies depending on the application, for example, a lithographic printing plate preferably has a solid content of 0.5 to 5.0 g / m ² .

The image forming material of the present invention has a wavelength of 4
It is preferable to perform image exposure using a light source of 00 nm or more, particularly 700 nm or more. Examples of the light source include a semiconductor laser, a He-Ne laser, a YAG laser, a carbon dioxide laser, and the like. The output is suitably 50 mW or more per laser beam, preferably 100 mW or more.

[3] Image Forming Method As a method for forming an image on the image forming material of the present invention, the photosensitive layer is exposed imagewise, and the exposed portion of the exposed layer is removed using a developing solution. It is preferable to use the above-mentioned infrared laser as a means for performing imagewise exposure. As a specific method, continuous processing is performed while adding a replenisher to the developer. In the present invention, since the sensitive layer component dissolved in the developer is limited to decomposed products that do not affect the developability, replenishment of the developer can be greatly reduced as compared with the conventional method, and therefore, the continuous use time of the developer can be reduced. , And a period in which replacement is unnecessary is secured for a long period of time, which leads to a large increase in the continuous processing amount. In addition, since the development process can be suppressed with a small amount of replenishment, the amount of waste liquid can be reduced, and an environmentally and hygienically excellent effect can be expected. In the present invention, the replenishing amount to the developer is preferably 100 ml or less, more preferably 50 ml or less per 1 m ² of the image forming material. Further, the volume is most preferably 25 ml or less. The replenishment amount per 1 m ² is an amount necessary to compensate for a decrease in developer activity due to the development processing of the image forming material. In order to detect this, measurement of the processing area of the image forming material, measurement of the conductivity, pH, and impedance of the developer, measurement of the amount of the sensitive layer component mixed into the developer, and the like are performed. Is added to the developer, but any method may be used for detection. The timing of replenishment is optional as long as it does not affect the development stability in continuous processing. As a replenishment for factors other than the development processing of the image forming material, replenishment is performed to compensate for a decrease in developer activity due to carbon dioxide gas in the air, but the replenishment amount specified in the claims of the present invention is exclude. However, if the replenishment amount corresponding to the development processing of the image forming material can be reduced, it is obvious that the replenishment for the influence of the carbon dioxide gas can be greatly reduced, which contributes to the reduction of the waste liquid amount.

As the developing solution and the developing replenisher used for the development, an aqueous alkaline developing solution is preferable. The aqueous alkali developer includes, for example, aqueous solutions of alkali metal salts such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium metasilicate, potassium metasilicate, dibasic sodium phosphate, and tertiary sodium phosphate. . The concentration of the alkali metal salt is 0.05 or more and 20
It is preferably used in the range of not more than 0.1% by weight, more preferably 0.1 to 10% by weight.

The silicate concentration / alkali metal concentration (molar concentration of SiO ₂ / molar concentration of alkali metal) of the developing solution and the developing replenisher is preferably 0.15 or more and 1.0 or less. Is preferably 0.5 to 5.0% by weight. Particularly preferably, the silicate concentration / alkali metal concentration of the developer is from 0.25 to 0.75, the silicate concentration is from 1.0 to 4.0% by weight, and the silicate concentration of the developer replenisher / alkali metal. The concentration is 0.15 or more and 0.5, and the silicate concentration is 1.0 or more and 3.0% by weight or less.

Further, Japanese Patent Application Laid-Open No.
A non-silicic acid-based developer described in JP-160631 A can also be used.

An anionic, nonionic, cationic or amphoteric surfactant or an organic solvent can be added to the developer, if necessary.

Examples of the anionic surfactant include higher alcohol sulfates having 8 to 22 carbon atoms such as sodium salt of lauryl alcohol sulfate, sodium salt of octyl alcohol sulfate, ammonium salt of lauryl alcohol sulfate and secondary sodium alkyl sulfate. Salts, for example, aliphatic alcohol sulfates such as sodium salt of acetyl alcohol sulfate, for example, alkylaryl sulfonates such as alkyl benzene sulfonates, alkyl naphthalene sulfonates, and sodium metanitrobenzene sulfonic acid; For example, C ₁₇ H ₃₃ CON (CH ₃ )
Examples include sulfonic acids of alkylamides such as CH ₂ CH ₂ SO ₃ Na, and sulfonates of dibasic fatty acid esters such as dioctyl sodium sulfosuccinate and sodium sulfosuccidihexyl ester.

[0182] Nonionic surfactants include those described in
Nos. -84241, 62-168160 and 62-
No. 175758, cationic surfactants disclosed in JP-A-62-175775, and amphoteric surfactants include, for example, alkyl carboxy betaine type, alkyl amino carboxylic acid type and alkyl imidazoline type compounds. Alternatively, an organic boron compound disclosed in Japanese Patent Publication No. 1-57895 can be used. The surfactant is suitably contained in the range of 0.1 to 5% by weight based on the total weight of the developing solution at the time of use.

Suitable organic solvents are those having a solubility in water of about 10% by weight or less, and preferably those having a solubility in water of 2% by weight or less. For example, 1-phenylethanol, 2-phenylethanol, 3-phenylpropanol, 1,4-phenylbutanol, 2,2-phenylbutanol, 1,2-phenoxyethanol, 2-benzyloxyethanol, o-methoxybenzyl alcohol, m- Examples thereof include methoxybenzyl alcohol, p-methoxybenzyl alcohol, benzyl alcohol, cyclohexanol, 2-methylcyclohexanol, 4-methylcyclohexanol, and 3-methylcyclohexanol. In the present invention, propylene glycol, ethylene glycol monophenyl ether, benzyl alcohol, n-propyl alcohol and the like are useful.

The content of the organic solvent is preferably 1 to 5% by weight based on the total weight of the developing solution at the time of use. The amount used is closely related to the amount used of the surfactant, and it is preferable to increase the amount of the surfactant as the amount of the organic solvent increases.

The developer may further contain, if necessary, additives such as an alkali-soluble mercapto compound and / or a thioether compound, a water-soluble reducing agent, an antifoaming agent and a water softener.

As the water softener, for example, Na ₂ P ₂ O ₇ ,
Polyphosphates such as Na ₃ PO ₉ , Na ₂ O (NaO ₃ P) PO ₃ Na ₂ , and cargon (sodium polymetaphosphate), for example, ethylenediaminetetraacetic acid, its potassium salt, its sodium salt: diethylenetriaminepentaacetic acid, its potassium salt , Sodium salt; triethylenetetramine hexaacetic acid, its potassium salt, its sodium salt; hydroxyethylethylenediaminetriacetic acid, its potassium salt,
Its sodium salt; nitrilotriacetic acid, its potassium salt, its sodium salt; 1,2-diaminocyclohexanetetraacetic acid, its potassium salt, its sodium salt;
Aminopolycarboxylates such as 1,3-diamino-2-propanoltetraacetic acid, its potassium salt and its sodium salt, and organic sulfones such as ethylenediaminetetra (methylenephosphonic acid) and its potassium and sodium salts Acid salts and the like can be mentioned. The optimum amount of such a water softener varies depending on the hardness of the hard water used and the amount used. However, if a general amount is used, 0.01 to 5% by weight in the developer at the time of use is used. , More preferably 0.01
It is contained in the range of 0.5% by weight.

Examples of the water-soluble reducing agent include phenolic compounds such as hydroquinone and methoxyquinone; amine compounds such as phenyleneamine and phenylhydrazine; sulfites such as sodium sulfite, potassium sulfite and sodium hydrogen sulfite; Examples include phosphites such as potassium and potassium hydrogen phosphite, sodium thiosulfate, sodium dithionite and the like. The content is preferably from 0.01 to 10% by weight based on the total weight of the developing replenisher.

The alkali-soluble mercapto compound and / or thioether compound is preferably a compound having at least one mercapto group and / or thioether group in the molecule and at least one acid group, and more preferably one compound per molecule. Compounds having at least one mercapto group and a carboxyl group are preferred. For example, mercaptoacetic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid,
4-mercaptobutanoic acid, 2,4-dimercaptobutanoic acid, 2-mercaptotetradecanoic acid, 2-mercaptomyristic acid, mercaptosuccinic acid, 2,3-dimercaptosuccinic acid, cysteine, N-acetylcysteine, N-
(2-mercaptopropionyl) glycine, N- (2-
Mercapto-2-methylpropionyl) glycine, N-
(3-mercaptopropionyl) glycine, N- (2-
Mercapto-2-methylpropionyl) cysteine, penicillamine, N-acetylpenicillamine, glycine / cysteine / glutamine condensate, N- (2,3-dimercaptopropionyl) glycine, 2-mercaptonicotinic acid, thiosalicylic acid, 3-mercaptobenzoic Acid, 4-mercaptobenzoic acid, 3-carboxy-2-mercaptopyridine, 2-mercaptobenzothiazole-5-carboxylic acid, 2-carcapto-3-phenylpropenoic acid, 2-
Mercapto-5-carboxyethylimidazole, 5-
Mercapto-1- (4-carboxyphenyl) tetrazole, N- (3,5-dicarboxyphenyl) -2-mercaptotetrazole, 2- (1,2-dicarboxyethylthio) -5-mercapto-1,3,3 4-thiadiazole, 2- (5-mercapto-1,3,4-thiadiazolylthio) hexanoic acid, 2-mercaptoethanesulfonic acid, 2,3-dimercapto-1-propanesulfonic acid,
2-mercaptobenzenesulfonic acid, 4-mercaptobenzenesulfonic acid, 3-mercapto-4- (2-sulfophenyl) -1,2,4-triazole, 2-mercaptobenzothiazole-5-sulfonic acid, 2-mercaptobenzo Imidazole-6-sulfonic acid, mercaptosuccinimide, 4-mercaptobenzenesulfonamide, 2
-Mercaptobenzimidazole-5-sulfonamide, 3-mercapto-4- (2- (methylaminosulfonyl) ethoxy) toluene, 3-mercapto-4- (2
-(Methylaminosulfonylamino) ethoxy) toluene, 4-mercapto-N- (p-methylphenylsulfonyl) benzamide, 4-mercaptophenol, 3-
Mercaptophenol, 3-mercaptophenol,
3,4-dimercaptotoluene, 2-mercaptohydroquinone, 2-thiouracil, 3-hydroxy-2-mercaptopyridine, 4-hydroxythiophenol, 4-
Hydroxy-2-mercaptopyrimidine, 4,6-dihydroxy-2-mercaptopyrimidine, 2,3-dihydroxypropylmercaptan, tetraethylene glycol, 2-mercapto-4-octylphenyl ether methyl ether, 2-mercapto-4-octylphenol methane Sulfonylaminoethyl ether, 2-mercapto-4-octylphenol methylaminosulfonylbutyl ether thiodiglycolic acid, thiodiphenol, 6,8-dithiooctanoic acid or an alkali metal thereof,
Examples thereof include salts with alkaline earth metals and organic amines.
The content of the above compound in the developer is suitably from 0.01 to 5% by weight.

In the present invention, known gum solutions and rinsing solutions can be used. The gum solution is preferably added with an acid or a buffer for removing an alkali component of the developer, and may further contain a hydrophilic polymer compound, a chelating agent, a lubricant, a preservative, a solubilizing agent, and the like. When the gum solution contains a hydrophilic polymer compound, it also has a function as a protective agent for preventing scratches and stains on the plate after development.

The surface condition of the coating layer is improved by adding a surfactant to the gum solution used in the present invention. Surfactants that can be used include anionic surfactants and / or nonionic surfactants. For example, anionic surfactants include fatty acid salts, abietic acid salts, hydroxyalkanesulfonates, alkanesulfonates, dialkylsulfosuccinates, linear alkylbenzenesulfonates, branched alkylbenzenesulfonates, alkylnaphthalene sulfones Acid salts,
Alkylphenoxy polyoxyethylene propyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, N-methyl-N-oleyltaurine sodium, N-alkyl sulfosuccinate monoamidini sodium, petroleum sulfonates, nitrated castor oil,
Sulfated tallow oil, sulfates of fatty acid alkyl esters, alkyl nitrates, polyoxyethylene alkyl ether sulfates, fatty acid monoglyceride sulfates, polyoxyethylene alkyl phenyl ether sulfates, polyoxyethylene styryl phenyl sulfate Ester salts, alkyl phosphate salts, polyoxyethylene alkyl ether phosphate salts, polyoxyethylene alkyl phenyl ether phosphate salts, partially saponified styrene-maleic anhydride copolymers, olefin-maleic anhydride copolymers Partially saponified compounds, naphthalene sulfonate formalin condensates, and the like are included. Of these, dialkyl sulfosuccinates, alkyl sulfates and alkyl naphthalene sulfonates are particularly preferably used.

Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene polystyryl phenyl ether, polyoxyethylene polyoxypropylene alkyl ether, glycerin fatty acid partial esters, Sorbitan fatty acid partial esters, pentaerythritol fatty acid partial esters, propylene glycol monofatty acid ester, sucrose fatty acid partial ester, polyoxyethylene sorbitan fatty acid partial ester, polyoxyethylene sorbitol fatty acid partial ester, polyethylene glycol fatty acid ester, poly Glycerin fatty acid partial esters, polyoxyethylated castor oil, polyoxyethylene glycerin fatty acid partial esters, fats Acid diethanol amides, N, N-
Examples include bis-2-hydroxyalkylamines, polyoxyethylene alkylamines, triethanolamine fatty acid esters, and trialkylamine oxides.
Among them, polyoxyethylene alkyl phenyl ethers, polyoxyethylene-polyoxypropylene block polymers and the like are preferably used. Also, fluorine-based,
Silicon-based anionic and nonionic surfactants can be used as well. Two or more of these surfactants can be used in combination. For example, two or more different types can be used in combination. For example, a combination of two or more different anionic surfactants or a combination of an anionic surfactant and a nonionic surfactant is preferable. The amount of the surfactant used is not particularly limited, but is preferably 0.01 to 20% by weight of the post-treatment solution.

In the gum solution used in the present invention, a polyhydric alcohol, an alcohol and an aliphatic hydrocarbon can be used as a lubricant, if necessary, in addition to the above components.

Of the polyhydric alcohols, preferred specific examples include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, tetraethylene glycol, polyethylene glycol, glycerin, sorbitol and the like. Alcohols such as alcohols, alkyl alcohols such as pentanol, hexanol, heptanol and octanol, and alcohols having an aromatic ring such as benzyl alcohol, phenoxyethanol and phenylaminoethyl alcohol are exemplified. Examples of the aliphatic hydrocarbon include n-hexanol, methyl amyl alcohol, 2-ethylbutanol, n-heptanol,
3-heptanol, 2-octanol, 2-ethylhexanol, nonanol, 3,5,5-trimethylhexanol, n-decanol, undecanol, n-dodecanol, trimethylnonyl alcohol, tetradecanol, heptadecanol, 2-ethyl- 1,3-hexanediol, 1,6-hexanediol, 2,5-hexanediol, 2,4-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, etc. No. The content of these lubricants is suitably from 0.1 to 50% by weight, more preferably from 0.5 to 3.0% by weight in the composition.

In addition to the above components, if necessary, lubricants such as ethylene glycol, propylene glycol, triethylene glycol, butylene glycol, hexylene glycol, diethylene glycol, dipropylene glycol,
Glycerin, trimethylolpropane, diglycerin and the like are preferably used. These wetting agents may be used alone or in combination of two or more. Generally, it is preferred that the wetting agent be used in an amount of 1 to 25% by weight.

Various hydrophilic polymers can be contained for the purpose of improving the film-forming properties.

As such a hydrophilic polymer, any polymer which can be conventionally used in a gum solution can be suitably used. For example, gum arabic, cellulose derivatives (eg, carboxymethylcellulose, carboxyethylcellulose, methylcellulose, etc.) and their modified products, polyvinyl alcohol and its derivatives, polyvinylpyrrolidone, polyacrylamide and its copolymers, vinyl methyl ether / maleic anhydride copolymer Examples include a polymer, a vinyl acetate / maleic anhydride copolymer, and a styrene / maleic anhydride copolymer.

Generally, it is more advantageous to use the gum solution used in the present invention in an acidic range, pH 3 to 6. In order to adjust the pH to 3 to 6, it is generally adjusted by adding a mineral acid, an organic acid or an inorganic salt to the post-treatment liquid. The addition amount is preferably 0.01 to 2% by weight. For example, mineral acids include nitric acid, sulfuric acid, phosphoric acid, and metaphosphoric acid.

Examples of the organic acid include citric acid, acetic acid, oxalic acid, malonic acid, p-toluenesulfonic acid, tartaric acid, malic acid, lactic acid, levulinic acid, phytic acid, and organic phosphonic acid. Further, as inorganic salts, magnesium nitrate, monobasic sodium phosphate, dibasic sodium phosphate,
Nickel sulfate, sodium hexamethanoate, sodium tripolyphosphate and the like can be mentioned. At least one kind or two or more kinds of mineral acids, organic acids or inorganic salts may be used in combination.

The gum solution used in the present invention includes a preservative,
An antifoaming agent or the like can be added.

Examples of preservatives include phenol or derivatives thereof, formalin, imidazole derivatives, sodium dehydroacetate, 4-isothiazolin-3-one derivatives,
Benzoisothiazolin-3-one, benztriazole derivatives, amidizing anidine derivatives, quaternary ammonium salts, derivatives such as pyridine, quinoline and guanidine, diazines, triazole derivatives, oxazoles, oxazine derivatives and the like. Preferred addition amounts are bacteria,
It is an amount that exerts a stable effect on mold, yeast, etc., and varies depending on the kind of bacteria, mold, yeast, but the range of 0.01 to 4% by weight based on the plate surface protective agent at the time of use. Preferred and effective against various molds and bacteria
It is preferable to use at least one preservative in combination. Further, as the defoaming agent, a silicone defoaming agent is preferable. Among them, any of emulsification dispersion type and solubilization can be used. Preferably, the range is 0.01 to 1.0% by weight based on the gum solution at the time of use.

Further, a chelate compound may be added. Preferred chelating compounds include, for example, ethylenediaminetetraacetic acid, its potassium salt, its sodium salt;
Diethylenetriaminepentaacetic acid, its potassium salt, its sodium salt; triethylenetetraminehexaacetic acid,
Its sodium salt; triethylenetetramine hexaacetic acid, its potassium salt, its sodium salt, hydroxyethylethylenediaminetriacetic acid, its potassium salt, its sodium salt: nitrilotriacetic acid, its sodium salt;
1-hydroxyethane-1,1-diphosphonic acid, its potassium salt and its sodium salt; organic phosphonic acids such as aminotri (methylenephosphonic acid), its potassium salt and its sodium salt, or phosphonoalkanetricarboxylic acids; Can be done. Organic amine salts are also effective in place of the sodium and potassium salts of the above chelating agents. These chelating agents are selected from those which are stably present in the gum solution composition and do not inhibit printability. The addition amount is suitably 0.001 to 1.0% by weight based on the gum solution at the time of use.

In addition to the above components, if necessary, a sensitizer may be added. For example, hydrocarbons such as turpentine oil, xylene, toluene, loheptane, solvent naphtha, kerosene, mineral spirit, and petroleum fraction having a boiling point of about 120 ° C. to about 250 ° C., for example, dibutyl phthalate, dihebutyl phthalate, di-n-octyl Phthalate diester agents such as phthalate, di (2-ethylhexyl) phthalate, dinonyl phthalate, didecyl phthalate, dilauryl phthalate, butyl benzyl phthalate and the like, for example, dioctyl adipate, butyl glycol adipate, dioctyl azelate, dibutyl sebacate, di ( Aliphatic dibasic acid esters such as 2-ethylhexyl) sebacate and dioctyl sebacate, for example, epoxidized triglycerides such as epoxidized soybean oil, for example, tricresyl phosphate, trioctyl phosphate Feto,
The solidification point of phosphoric esters such as trischlorethyl phosphate, for example, benzoic esters such as benzyl benzoate, is 15 ° C. or less, and the boiling point at 1 atm is 300 ° C.
The above plasticizer is included.

Further, caproic acid, enanthic acid, caprylic acid, helargonic acid, capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid,
Saturated fatty acids such as palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachiic acid, behenic acid, lignoceric acid, cerotic acid, heptacosanoic acid, montanic acid, melicic acid, laccelic acid, isovaleric acid, and acrylic acid, crotonic acid, Such as isocrotonic acid, undecylenic acid, oleic acid, elaidic acid, setreic acid, nilucic acid, butesidic acid, sorbic acid, linoleic acid, linolenic acid, arachidonic acid, propiolic acid, stearolic acid, succinic acid, tallic acid, and licanoic acid Also included are unsaturated fatty acids. More preferably a fatty acid that is liquid at 50 ° C.,
More preferably, it has 5 to 25 carbon atoms, and most preferably, it has 8 to 21 carbon atoms. These sensitizers can be used alone or in combination of two or more. The preferred range is 0.01 to 10% by weight of the gum, and the more preferred range is 0.05 to 5% by weight.

[0204] The above oil-sensitizing agent may be prepared by emulsifying and dispersing a gum and may be contained as an oil phase thereof, or may be solubilized with the aid of a solubilizing agent.

In the present invention, the solid concentration of the gum solution is 5%.
-30 g / l is preferred. The gum film thickness can be controlled by the conditions of the squeezing means of the automatic processing machine. In the present invention, the amount of gum applied is preferably 1 to 10 g / m ² . If the gum application amount exceeds 10, the plate surface needs to be heated to a very high temperature in order to dry in a short time, which is disadvantageous in terms of cost and safety, and the effect of the present invention cannot be sufficiently obtained. If the amount is less than 1 g / m ² , uniform coating becomes difficult, and stable processability cannot be obtained.

In the present invention, the time from the end of application of the gum solution to the start of drying is preferably 3 seconds or less. More preferably, it is 2 seconds or less, and the shorter this time is, the better the ink deposition property is.

The drying time is preferably 1 to 5 seconds. When the drying time exceeds 5 seconds, the effect of the present invention cannot be obtained. If the drying time is less than 1 second, it is necessary to heat the plate surface to a very high temperature in order to sufficiently dry the photosensitive lithographic printing plate, which is not preferable in terms of safety and cost. As a drying method, a known drying method such as a warm air heater or a far infrared heater can be used. In the drying step, the solvent in the gum solution needs to be dried.

For that purpose, it is necessary to secure a sufficient drying temperature and heater capacity. The temperature required for drying depends on the components of the gum solution, but in the case of a gum solution in which the solvent is water, the drying temperature is usually preferably 55 ° C. or higher.
Heater capacity is often more important than drying temperature,
Its capacity is preferably 2.6 kW or more in the case of the hot air drying method. The larger the capacity, the better, but it is preferably 2.6 to 7 kW in terms of cost.

The developing process is described in, for example, JP-A-5-18860.
No. 1 and Japanese Patent Application No. 9-143882 are effective. As the developing solution, erasing solution and post-processing solution, the processing agents described in Japanese Patent Application No. 8-56894 can be used.

[0210]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto. In addition, "part"
Indicates "parts by weight".

(Preparation of photosensitive lithographic printing plate) Thickness 0.24
JIS-1050 aluminum plate of 10 mm at 85 ° C.
% Sodium hydroxide aqueous solution, degreased for 1 minute, and then washed with water. The degreased aluminum plate was immersed in a 10% aqueous sulfuric acid solution at 25 ° C. for 1 minute, desmutted, and then washed with water. Next, the aluminum plate was placed in a 1.0% aqueous nitric acid solution at a temperature of 30 ° C.
It was electrochemically roughened so that the amount of electricity 400c / dm ² at a current density of 50A / dm ^2. Then, at 50 ° C
Chemical etching was performed so that the amount of aluminum dissolved in a 3% aqueous sodium hydroxide solution was 3 g / m ² . Next, it is immersed in a 10% aqueous nitric acid solution at 25 ° C. for 10 seconds,
After the desmut treatment, it was washed with water. Then, at 35 ° C., 20
Anodizing treatment was performed in an aqueous solution of 2% sulfuric acid at a current density of 2 A / dm ² for 1 minute. Then, it was immersed in a 0.1% ammonium acetate aqueous solution at 80 ° C. for 30 seconds to perform a sealing treatment, and dried at 80 ° C. for 5 minutes. On one surface (back surface) of this aluminum plate, a JIS No. 3 sodium silicate aqueous solution (10 g / l) was applied using a wire bar,
For 3 minutes to prepare an aluminum support having a coating layer on the back surface. The coating layer has a dry weight of 10 mg / m
^It was applied so as to be ² .

Example 1 A lithographic printing plate 1 was obtained by applying a coating solution for a sensitive layer having the following composition on the support so that the film thickness after drying was 2 g / m ² and drying at 100 ° C. for 2 minutes. Was.

(Sensitive layer coating solution positive type) Binder A 70 parts Binder B 5 parts Acid-decomposable compound (Compound of Synthesis Example A-1) 20 parts Acid generator Exemplified compound S-1 3 parts Infrared absorber Exemplified compound IR53 1 part Crystal violet 0.3 part Fluorinated surfactant S-381 (manufactured by Asahi Glass) 0.5 part Methyl lactate 700 parts MEK 200 parts Binder A: Co-condensation of phenol, m-, p-mixed cresol and formaldehyde Novolak resin (M
w = 4000, and the molar ratio of phenol / m-cresol / p-cresol is 5/57/38, respectively) Binder B: copolymer of methyl methacrylate / hydroxyphenyl methacrylamide / methacrylamide / methacrylonitrile (copolymer weight ratio = 20/20/3
(0/30, Mw = 30000) MEK: methyl ethyl ketone An image was formed on the obtained lithographic printing plate material by the following method.

Exposure machine manufactured by Creo Products (Trend setter 3244; equipped with a semiconductor laser having an oscillation wavelength of 830 nm, laser output 10 W, 240 channel machine)
The image exposure was performed on the surface of the sensitive layer.

Next, an automatic developing machine PSZ- manufactured by Konica Corporation was used.
910 was used for development and washing. An aqueous solution having the following composition was used as a developer. 25 L of a developing solution was charged into the developing tank, a developing process was performed at a developing time of 12 seconds and a developing temperature of 32 ° C., and then a rinsing process was performed.

(Composition of Developer 1) Potassium A silicate 100.0 parts Potassium hydroxide 24.5 parts Caprylic acid 0.2 parts Maleic acid 2.0 parts EDTA 0.3 parts Water 1840 parts Lithographic plate after development processing The printing plate was evaluated for sensitivity, storability and safelight properties as follows.

(Evaluation)-Sensitivity-The sensitivity is defined as the exposure energy at which the sensitive layer in the exposed area can be removed.

-Storage Property- After storing at 50 ° C. and 80% RH for 3 days, the exposure energy at the time of developing the lithographic printing plate was defined as sensitivity, and the sensitivity was evaluated as storage property.

-Safelight Property- The composition was exposed to 1000 LUX under a white fluorescent lamp, and after developing the lithographic printing plate, the residual ratio of the sensitive layer in the image area was evaluated. 10
The time to divide 0% was examined.

Lithographic printing plates 2 to 10 were prepared by changing the acid generator as shown in Table 1, and exposed and developed in the same manner, and evaluated. The results obtained are shown in Table 1 below.

[0221]

[Table 1]

[0222]

Embedded image

As is apparent from Table 1, the wavelength was 400 nm.
The lithographic printing plates 1 to 9 of the present invention having an acid generator having no absorption band as described above have excellent sensitivity and also exhibit excellent preservability with little sensitivity fluctuation, and also exhibit excellent safelight properties. You can see that However, the comparative example has a wavelength of 40
It can be seen that since an acid generator having an absorption band at 0 nm or more is used, sensitivity fluctuation is large and safelight properties are not improved.

Example 2 The procedure of Example 1 was repeated except that the acid-decomposable compound in the composition for the sensitive layer was changed to hexamethoxymethylolmelamine (negative type), and the acid generator was changed as shown in Table 2. A lithographic printing plate 11 was prepared, exposed, developed, and evaluated. However, after exposure and before development, heat treatment was performed at 140 ° C. for 30 seconds. At this time, the unexposed portion of the sensitive layer was removed by development. In addition, here, it evaluated as follows.

(Evaluation)-Sensitivity-The sensitivity is defined as the exposure energy at which the sensitive layer in the exposed area can be removed.

-Preservability- After storing at 50 ° C. and 80% RH for 3 days, the background stain when the lithographic printing plate was developed was evaluated.

・ ・ ・: Not generated at all △: Slightly generated X: Stain is conspicuous.

-Safelight Property- Under a white fluorescent lamp, the lithographic printing plate was exposed to light at 1000 LUX, the background stain was evaluated, and the time until the background stain occurred was examined. The results obtained are shown in Table 2 below.

[0229]

[Table 2]

As is clear from Table 2, a wavelength of 400 nm
The lithographic printing plates 11 to 19 of the present invention having an acid generator having no absorption band as described above have excellent sensitivity and excellent storage stability with little fluctuation in sensitivity, while having excellent safelight properties. It can also be seen that However, it can be seen that the comparative example uses an acid generator having an absorption band at a wavelength of 400 nm or more, so that the sensitivity varies greatly and the safelight property is not improved.

[0231]

The image-forming material of the present invention contains an acid generator which does not absorb light of 400 nm or more, so that CTP
Even when an image is formed by infrared laser exposure, excellent effects of excellent sensitivity and storability and improving the handling of a user in a bright room can be obtained.

Claims (5)

[Claims] 1. A sensitive layer containing a dye sensitive to a wavelength of 700 to 1200 nm, a compound having a bond decomposable by an acid, and an acid generator that does not absorb light of 400 nm or more is provided on a support. An image forming material comprising: 2. A sensitive layer containing, on a support, a dye sensitive to a wavelength of 700 to 1200 nm, a compound insolubilizable in alkali in the presence of an acid, and an acid generator that does not absorb light of 400 nm or more. An image forming material comprising: 3. The image forming material according to claim 1, wherein the acid generator is at least one selected from an organic halogen compound and a diphenyliodonium salt. 4. The image forming method according to claim 3, wherein said organic halogen compound is an s-triazine compound. 5. The image forming material according to claim 1, wherein said sensitive layer is water-insoluble and contains an alkali-water-soluble resin component.