JP2000199950A - Image forming material and image forming method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming material high with sensitivity to infrared rays and requiring no heat treatment after exposure and small affected by fluctuation of developing conditions and suitable to a large amount of develop ment processings by providing a image forming layer containing a novolak resin, infrared-absorbing material and resin having specified cyano groups. SOLUTION: This image forming material is provided on a support with the image forming layer changing its solubility in an aqueous alkaline developing solution on the exposed areas of the layer by imagewise exposing it to infrared laser beams. The image forming layer contains a novolak resin and an infrared absorbing material and a resin having cyano groups and repeating structural units represented by the formula, in which X is an alkylene or arylene group; (m) is 0 or 1; Y is a -COO- or -CONH- group; (n) is 0 or 1; and R1 is an H atom or an alkyl or hydroxyalkyl group or the like, thus permitting the obtained image forming material to be high in sensitivity with respect to infrared light, does not require heat treatment after exposure, and is hardly affected small by fluctuation of developing conditions.

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 having a photosensitive layer whose solubility in an aqueous developing solution is changed by actinic light and an image forming method using the same. The present invention relates to an image forming material capable of forming an image by exposure and suitable for a photosensitive lithographic printing plate and the like, and an image forming method using the same.

[0002]

2. Description of the Related Art Many image forming materials recordable with an infrared laser have been proposed, and among these image forming materials, proposals have been made for using a printing plate. Many of these are provided with an infrared-sensitive lipophilic layer coated on a hydrophilic support. A method is used in which a difference is caused in solubility in a developer and an image is formed by elution development.

For example, Japanese Patent Application Laid-Open No. 7-20629 discloses an image forming material applicable to a printing plate material by combining a novolak resin, a resol resin, an acid generator (latent Bronsted acid) and an infrared dye. Has been proposed. However, this material has a problem that the sensitivity to infrared laser light is not always sufficient, and image-wise scanning exposure requires a long time. In order to cover this, a method of performing heat treatment after performing image scanning exposure in a short time has also been proposed, but a large-scale facility for heat treatment is required, or an image due to fluctuations in heat treatment conditions is required. There were problems such as variations in reproducibility.

[0004] As a material which does not require heat treatment after imagewise scanning exposure, WO 97/39894 is combined with a polymer compound soluble in an aqueous developer and a substance reducing the solubility of the polymer compound. Materials have been proposed.
However, in this material, the difference between the solubility of the exposed part and the unexposed part in the developing solution after exposure is small, and the variation in image reproducibility due to fluctuations in conditions such as the concentration, composition, temperature, and developing time of the developing solution is large. However, there was a problem in the actual printing operation. Furthermore, when this material is subjected to a large amount of development with a certain amount of developing solution, compared to the plate developed earlier, the plate developed later has a reduced image portion or a non-image portion. There was a problem of poor elution. In addition, there is a problem that the printing durability is insufficient when subjected to printing because the process such as heat treatment is not performed.

[0005]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems of the prior art, and has a high sensitivity to infrared light, does not require a heat treatment after exposure, and is free from fluctuations in development conditions. An object of the present invention is to provide an image forming material which is not easily affected and is suitable for a large amount of development processing, and to provide an image forming material which is excellent in printing durability and suitable for a printing plate.

[0006]

The constitution of the present invention which achieves the above object of the present invention is as follows.

(1) An image forming layer comprising a novolak resin, an infrared absorber and a cyano group-containing resin containing a repeating structural unit represented by the following general formula (1) is provided on a support. Image forming material.

[0008]

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[In the formula, X represents an alkylene group or an arylene group, m represents 0 or 1, and Y represents -COO- or-
Represents CONH-, n represents 0 or 1, R ₁ represents a hydrogen atom, an alkyl group, a hydroxyalkyl group, an alkoxyalkyl group or a halogenated alkyl group. (2) An image-forming material having, on a support, an image-forming layer whose solubility in an alkaline aqueous developer changes by imagewise scanning exposure with infrared laser light,
An image forming material, wherein the image forming layer contains a novolak resin and a cyano group-containing resin containing a repeating structural unit represented by the following general formula (1).

[0010]

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[Wherein, X represents an alkylene group or an arylene group, m represents 0 or 1, and Y represents -COO- or-
Represents CONH-, n represents 0 or 1, R ₁ represents a hydrogen atom, an alkyl group, a hydroxyalkyl group, an alkoxyalkyl group or a halogenated alkyl group. (3) The image forming material as described in the above (1) or (2), wherein the repeating structural unit represented by the general formula (1) is the following general formula (2).

[0012]

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[In the formula, R ₂ represents an alkyl group, a hydroxyalkyl group, an alkoxyalkyl group or a halogenated alkyl group. (4) The image forming layer comprises a compound having a plurality of aromatic OH groups, wherein a part or all of the aromatic OH groups are represented by the following general formula (3)
The image forming material according to the above (1), (2) or (3), comprising a sulfonic acid ester compound substituted with a substituent having the structure:

Formula (3) R ₃ —SO ₂ —O— wherein R ₃ represents an alkyl group, an alkenyl group, a cycloalkyl group, a phenyl group or an alkyl-substituted phenyl group. (5) Novolak resin, infrared absorber,
And a sulfonic acid ester compound in which a part or all of the aromatic OH groups of a compound having a plurality of aromatic OH groups are substituted with a substituent having a structure represented by the following general formula (3). material.

Formula (3): R ₃ —SO ₂ —O— wherein R ₃ represents an alkyl group, an alkenyl group, a cycloalkyl group, a phenyl group or an alkyl-substituted phenyl group. (6) An image-forming material having, on a support, an image-forming layer in which the solubility of an exposed portion in an alkaline aqueous developer is changed by imagewise scanning exposure with infrared laser light,
The image forming layer comprises a novolak resin and a compound having a plurality of aromatic OH groups, in which a part or all of the aromatic OH groups are substituted with a substituent having a structure represented by the following general formula (3). An image forming material characterized by containing.

Formula (3): R ₃ —SO ₂ —O— wherein R ₃ represents an alkyl group, an alkenyl group, a cycloalkyl group, a phenyl group or an alkyl-substituted phenyl group. (7) The image forming material as described in (4), (5) or (6) above, wherein the compound having a plurality of aromatic OH groups is pyrogallol.

(8) The image forming material as described in any one of (4) to (6) above, wherein the compound having a plurality of aromatic OH groups is polyhydroxybenzophenone. (9) The compound according to any one of the above (4) to (6), wherein the compound having a plurality of aromatic OH groups is a compound having a structural unit represented by the following general formula (4) in the molecule. 2. The image forming material according to item 1.

[0018]

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[In the formula, R ₄ represents a hydrogen atom or an alkyl group having 1 to 9 carbon atoms. R ₅ represents a hydrogen atom or a methyl group. R ₆ represents a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group or a phenyl group. a
Represents an integer of 1 to 3. (10) The image forming layer according to any one of the above (1) to (9), wherein the image forming layer contains a compound that generates an acid by being decomposed, and a compound that is decomposed by the presence of the acid. The image forming material as described in the above.

(11) The above-mentioned (1) to (1), wherein the image forming layer contains a compound which generates an acid by being decomposed and a compound which is crosslinked by the presence of the acid.
The image forming material according to any one of (9).

(12) The above (1) to (1), wherein the surface of the support on which the image forming layer is coated is hydrophilic.
(11) The image-forming material according to any one of (1) to (12), after the image-forming material according to any one of (1) to (12) is image-wise scanned and exposed to infrared laser light. An image forming method comprising: eluting and removing a non-image portion with an alkaline aqueous developer.

Hereinafter, the present invention will be described in detail.

The image forming material of the present invention is characterized in that the image forming layer provided on the support has the following structure or the following structure.

A positive image forming layer containing a novolak resin, an infrared absorber, and at least one selected from the above-mentioned cyano group-containing resins and the above-mentioned sulfonic acid ester compounds.

A positive image forming layer further comprising a compound capable of generating an acid by decomposition and a compound decomposing by the presence of an acid in the above image forming layer.

A negative-type image forming layer further comprising a compound capable of generating an acid upon decomposition and a compound cross-linking in the presence of the acid.

The novolak resin used in the present invention includes:
For example, phenol-formaldehyde resin, cresol-formaldehyde resin, phenol-cresol-formaldehyde copolycondensate resin as described in JP-A-55-57841, JP-A-55-1275
No. 53, a copolycondensate resin of p-substituted phenol and phenol or cresol and formaldehyde, and the like.

The proportion of the novolak resin in the image forming layer is not particularly limited, but is preferably 50 to 95% by weight.

The cyano group-containing resin used in the present invention is a homopolymer or a copolymer having a repeating structural unit represented by the general formula (1). The structural unit is, specifically, acrylonitrile, methacrylonitrile, 4-cyanostyrene, o-cyanostyrene, m-cyanostyrene, 4-cyanophenylacrylate, 4-cyanophenylmethacrylate, 2- (4-cyanobenzoyl) Oxy) ethyl acrylate, 2- (4-cyanobenzoyloxy) ethyl methacrylate, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, 2-cyanoethyl methacrylate, represented by the general formula (2) Cyano group-containing monomers having a structure, for example, methyl-2-cyanoacrylate, ethyl-
Homopolymerization using one or more cyano group-containing monomers selected from 2-cyanoacrylate, propyl-2-cyanoacrylate, methoxyethyl-2-cyanoacrylate, and the like, or copolymerization with another copolymerizable monomer I can guide you. Among the above-mentioned cyano group-containing monomers, a cyano group-containing monomer having a structure represented by the general formula (2), for example, methyl-
2-cyanoacrylate, ethyl-2-cyanoacrylate, propyl-2-cyanoacrylate, methoxyethyl-2-cyanoacrylate and the like.

Other monomers to be copolymerized with these cyano group-containing monomers are optional, but specific examples include the following monomers (1) to (15).

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

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

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

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

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

(6) Substituted or unsubstituted alkyl acrylates, for example, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonyl acrylate , Decyl acrylate,
Undecyl acrylate, dodecyl acrylate, benzyl acrylate, cyclohexyl acrylate, acrylic acid
2-chloroethyl, N, N-dimethylaminoethyl acrylate, glycidyl acrylate and the like.

(7) Substituted or unsubstituted alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate Decyl methacrylate, undecyl methacrylate, dodecyl methacrylate, benzyl methacrylate, cyclohexyl methacrylate, 2-chloroethyl methacrylate, N, N-dimethylaminoethyl methacrylate, glycidyl methacrylate and the like.

(8) Acrylamide or methacrylamides such as acrylamide, methacrylamide,
N-ethylacrylamide, N-hexylacrylamide, N-cyclohexylacrylamide, N-phenylacrylamide, N-nitrophenylacrylamide,
N-ethyl-N-phenylacrylamide and the like.

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

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

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

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

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

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

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

The ratio of the cyano group-containing resin in the image forming layer is not particularly limited, but is preferably 1 to 50% by weight.

The sulfonic acid ester compound used in the present invention is a compound having a plurality of aromatic OH groups in which some or all of the aromatic OH groups are substituted with a substituent having the structure of the general formula (3). is there. The compound having a plurality of aromatic OH groups is optional, but preferred specific examples include pyrogallol, polyhydroxybenzophenones, and compounds having a structural unit represented by the above general formula (4) in the molecule. As a means for deriving a sulfonic acid ester compound from a compound having a plurality of aromatic OH groups, for example, a sulfonic acid chloride having a structure represented by the following general formula (5) may be used in the presence of a basic compound in the presence of a corresponding aromatic compound. There is a method of acting on a compound having a plurality of group OH groups.

Formula (5) R ₃ —SO ₂ —Cl In Formula (5), R ₃ represents an alkyl group, an alkenyl group, a cycloalkyl group, a phenyl group or an alkyl-substituted phenyl group.

Specific examples of the sulfonic acid ester compound of the present invention include, but are not limited to, the following compounds.

[0050]

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[0051]

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The proportion of the sulfonic acid ester compound in the image forming layer is not particularly limited, but is preferably 1 to 20% by weight.

The cyano group-containing resin of the present invention and an aromatic OH
It is preferable to use together with a sulfonic acid ester compound in which a part or all of the aromatic OH group of the compound having a plurality of groups is substituted with a substituent having the structure of the general formula (3).

<< Infrared absorbing agent >> As the infrared absorbing agent used in the present invention, an infrared absorbing dye having absorption at a wavelength of 700 nm or more, carbon black, magnetic powder and the like can be used. Particularly preferred infrared absorbers are 700 to 85
It has an absorption peak at 0 nm and the molar extinction coefficient ε at the peak
Is 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.

Further, as the above-mentioned infrared absorbing dye, JP-A-6
3-139191 and 64-33547, JP-A-1
-160683, 1-280750, 1-29
No. 3342, No. 2-2074, No. 3-26593,
3-30991, 3-34891, 3-36
Nos. 093, 3-36094, 3-36095,
The compounds described in JP-A-3-42281 and JP-A-3-103476 are exemplified.

In the present invention, a cyanine dye represented by the following general formula (6) or (7) is particularly preferred as the infrared absorbent.

[0058]

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In the general formula (6) or (7), Z ₁ and Z ₂ each represent a sulfur atom, a selenium atom or an oxygen atom, and X ₁ and X ₂ each represent a benzo-condensed group which may have a substituent. A nonmetallic atom group necessary for forming a ring or a naphtho condensed ring; R ₃ and R ₄ each represent a substituent; 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 the general formula (6) or (7) include those in which the general formula (6) or (7) forms a cation and has a counter anion. In this case, as the counter anion, Cl ⁻ , Br ⁻ , ClO ₄ ⁻ , BF ₄ ⁻ ,
Alkyl boron such as t-butyltriphenylboron and the like can be mentioned.

In the general formulas (6) and (7), the number of carbon atoms (n) in the chain of conjugated bonds represented by L is determined when a laser emitting infrared light is used 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 an arbitrary substituent, and the conjugate bond may form a ring with a plurality of substituents. In the general formulas (6) and (7), the ring represented by X ₁ and the ring represented by X ₂ can have an arbitrary substituent. As the substituent, a halogen atom, an alkyl group having 1 to 5 carbon atoms, 1 to 5 carbon atoms
And a group selected from —SO ₃ M and —COOM (M is a hydrogen atom or an alkali metal atom). R ₃ and R ₄ are each an arbitrary substituent, but are 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 ) _m OR (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. One of R ₃ and R ₄ is —R—SO ₃ M and the other is —
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-COOM other hand 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 -R-SO ₃ of R ₄ ^- or -R-COO ^-, it is preferred the other is -R-SO ₃ M or -R-COOM.

The cyanine dye represented by formula (6) or (7) has an absorption peak at 750 to 900 nm when a semiconductor laser is used as a light source for image exposure, and at 900 to 1200 nm when a YAG laser is used. And those having a molar extinction coefficient of ε> 1 × 10 ⁵ are preferred.

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

[0064]

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[0065]

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[0066]

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[0067]

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[0068]

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[0069]

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[0070]

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[0071]

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[0072]

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[0073]

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[0074]

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[0075]

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[0076]

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[0077]

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[0078]

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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, SIR103 (phthalocyanine-based); KIR101, SIR114 (anthraquinone-based); PA1001, PA1005, PA1006, S
IR128 (metal complex type) Dainippon Ink and Chemicals: Fastogen blue 812
0 Midori Kagaku: MIR-101, 1011, 1021 Others are also commercially available from companies such as Nippon Kogaku Dyestuffs, Sumitomo Chemical, and Fuji Photo Film.

In the present invention, the amount of the infrared absorbent added is preferably in the range of 0.5 to 5 wt%. When the amount added is 5
If the content exceeds wt%, the developability of the non-image portion (exposed portion) decreases, and if the content is less than 0.5 wt%, the development resistance of the image portion decreases.

According to a tenth aspect of the present invention, in the image forming layer according to the first to ninth aspects of the present invention, a compound capable of generating an acid by decomposition and a compound decomposing by the presence of an acid are contained. The invention according to claim 11 is a negative type wherein the image forming layer according to any one of claims 1 to 9 contains a compound that generates an acid when decomposed and a compound that cross-links due to the presence of the acid to form a negative type. It is.

In the invention according to claim 10 or 11,
Examples of the compound that generates an acid by decomposition (hereinafter, referred to as “acid-generating compound”) include various known compounds and mixtures. For example, diazonium, phosphonium, sulfonium and iodonium BF ₄ ⁻ , PF
^{_{6 -, SbF 6 -, SiF}} 6 2-, ClO 4 - , an organic halogen containing compound, ortho-quinone - diazide sulfonyl chloride, and formation or separation of the acid during the organometal / organohalogen compounds also show activity beam irradiation Actinic ray-sensitive component, and can be used as the compound that generates the acid of the present invention. In principle, all organic halogen compounds known as free-radical-forming photoinitiators are compounds which form hydrohalic acids and can be used as the acid-generating compounds according to the invention.

Examples of the compounds forming the above-mentioned hydrohalic acid include US Pat. No. 3,515,552,
Nos. 3,536,489 and 3,779,778
And compounds described in West German Patent Publication No. 2,243,621 and which generate an acid by photolysis described in West German Patent Publication No. 2,610,842, for example. Can also be used.

Further, o-naphthoquinonediazido-4-sulfonic acid halogenide described in JP-A-50-36209 can be used.

In the invention according to the tenth aspect, an organic halogen compound is preferable as the acid-generating compound from the viewpoints of sensitivity in image formation by infrared exposure and storage stability of the image forming material. As the organic halogen compound, triazines having a halogen-substituted alkyl group and oxadiazoles having a halogen-substituted alkyl group are preferable,
Particularly preferred are s-triazines having a halogen-substituted alkyl group.

Specific examples of oxadiazoles having a halogen-substituted alkyl group are described in JP-A-54-74728.
2-halomethyl-1,3,4-oxadiazole-based compounds described in JP-A Nos. 55-24113, 55-77742, 60-3626 and 60-138439. 2-halomethyl-1,3,4-
Preferred examples of the compound that generates an oxadiazole-based acid are shown below.

[0088]

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S- having the halogen-substituted alkyl group
As the triazine, a compound represented by the following general formula (8) is preferable.

[0090]

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In the general formula (8), R represents an alkyl group,
A halogen-substituted alkyl group, a phenylvinylene group or an aryl group (for example, a phenyl group, a naphthyl group or the like) which may be substituted with an alkoxy group, or a substituted product thereof;
X represents a halogen atom.

The following are examples of compounds that generate an s-triazine acid represented by the general formula (8).

[0093]

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[0094]

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In the invention according to claim 10 or 11,
The content of the acid-generating compound can vary widely depending on its chemical properties and the composition or physical properties of the photosensitive layer of the image-forming material of the present invention. A suitable range is from 0.1 to about 20% by weight, preferably from 0.2 to 10% by weight.

Compounds which decompose in the presence of an acid (hereinafter referred to as "acid-decomposable compounds") used in the invention according to claim 10 are specifically described in JP-A-48-89003 and JP-A-48-90303.
1-120714, 53-133429, 55
-12995, 55-126236, 56-1
Compounds having a C-O-C bond described in each of JP-A-7345 and JP-A-60-37549;
No. 1446, compounds having a Si--O--C bond described in JP-A Nos. 60-3625 and 60-1025.
247. Other acid-decomposable compounds described in each publication. Furthermore, a compound having an Si-N bond described in Japanese Patent Application No. 61-16687 is disclosed.
94603, the orthocarbonate described in Japanese Patent Application No. 60-251744, the orthotitanate described in Japanese Patent Application No. 61-125473, and the like. Noboru 61-
Orthosilicate described in Japanese Patent Application No. 125474, acetal and ketal described in Japanese Patent Application No. 61-155481, Japanese Patent Application No. 61-8776.
No. 9 having a CS bond.

Of the above, the above-mentioned JP-A-53-13342
No. 9, 56-17345, 60-12446
Nos. 60-37549 and Japanese Patent Application No. 60-25.
Compounds having a C—O—C bond described in each of the specifications of Nos. 1744 and 61-155481, Si—O—C
Compounds having a bond, orthocarbonates, acetals, ketals and silyl ethers are preferred.

Among them, JP-A-53-13342
Japanese Patent Application Laid-Open No. Sho 63-93, which discloses an organic polymer compound having a repeating acetal or ketal moiety in the main chain thereof and whose solubility in a developer is increased by the action of an acid.
The following structural units described in JP-A-10153.

[0099]

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Compounds having the formula and which can be decomposed by an acid are particularly preferred.

Specific examples of the acid-decomposable compound used in the present invention include the compounds described in the above publications and specifications. The method for synthesizing the compound is described in each of the above-mentioned publications and in the specification.

In the present invention, the acid-decomposable compound is-
A compound having a (CH ₂ CH ₂ O) _n -group (n represents an integer of 2 to 5) is preferred from the viewpoint of the balance between sensitivity and developability. Further, among these compounds, a compound in which the number of chains n of the ethyleneoxy group is 3 or 4 is particularly preferable. The above-(CH ₂
Specific examples of the compound having a CH ₂ O) _n -group include a condensation product of dimethoxycyclohexane, benzaldehyde and a substituted derivative thereof with any one of diethylene glycol, triethylene glycol, tetraethylene glycol, and pentaethylene glycol. .

In the present invention, as the acid-decomposable compound, a compound represented by the following general formula (9) is preferable from the viewpoint of sensitivity and developability.

[0104]

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Wherein R, R ₁ and R ₂ are each a hydrogen atom,
Represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a sulfo group, a carboxyl group or a hydroxyl group, p, q and r each represent an integer of 1 to 3, and m and n Represents an integer of 1 to 5, respectively.

In the general formula (9), the alkyl group represented by R, R ₁ and R ₂ may be linear or branched, for example, methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, Examples include a pentyl group, and examples of the alkoxy group include a methoxy group, an ethoxy group,
Propoxy group, isopropoxy group, butoxy group, ter
Examples thereof include a t-butoxy group and a pentoxy group, and the sulfo group and the carboxyl group include salts thereof. General formula (9)
Among the compounds represented by the formula, compounds wherein m and n are 1 or 2 are particularly preferred. The compound represented by the general formula (9) can be synthesized by a known method.

In the present invention, the content of the acid-decomposable compound is 5 to the total solid content of the composition for forming the image forming layer.
It is preferably from 70 to 70% by weight, particularly preferably from 10 to 50% by weight. One type of acid-decomposable compound may be used,
Mixtures of more than one species may be used.

In the invention according to the eleventh aspect, the compound which is cross-linked by the presence of an acid contained in the image forming layer (hereinafter referred to as “acid cross-linking compound”) includes, as a functional group, an alkoxymethyl group, a methylol group, an acetoxymethyl group and the like. Having at least two amino acids, for example, a melamine derivative [hexamethoxymethylated melamine (Cymel 300 series (1) manufactured by Mitsui Cyanamid Co., Ltd.)
Benzoguanamine derivatives [methyl / ethyl mixed alkylated benzoguanamine resin (Cymel 1100 series (2) manufactured by Mitsui Cyanamid Co., Ltd.)), glycoluril derivatives [tetramethylol glycoluril (Mitsui Cyanamid Co., Ltd., Cymel 1100 series) (3)) and the like, and at least a disubstituted aromatic compound having an alkoxymethyl group, a methylol group, an acetoxymethyl group or the like as a functional group, for example, 1,3,5-
Triacetoxymethylbenzene, 1,2,4,5-tetraacetoxymethylbenzene, and the like.
olym. Master. Sci. Eng. , 64 ,
241 (1991).

As the acid crosslinking agent, resole resins and furan resins can also be used in addition to the above. Further, an acrylic resin synthesized from monomers including the following monomers can be used.

N-methylolacrylamide, N-methylolmethacrylamide, N, N-dimethylolacrylamide, N, N-dimethylolmethacrylamide, N-methylolacrylamide
-(2-hydroxyethyl) acrylamide, N- (2
-Hydroxyethyl) methacrylamide, N, N-di (2-hydroxyethyl) acrylamide, N, N-di (2-hydroxyethyl) methacrylamide, N-hydroxymethyl-N- (2-hydroxyethyl) acrylamide, N -Hydroxymethyl-N- (2-hydroxyethyl) methacrylamide, hydroxyethyl vinyl ether, vinylbenzyl alcohol, α-methylvinylbenzyl alcohol, vinylbenzyl acetate, α-
An embodiment in which any one of methylvinylbenzyl acetate, vinylphenethyl alcohol, α-methylvinylphenethyl alcohol, vinylphenethyl acetate, and α-methylvinylphenethyl acetate is copolymerized in an amount of 1 to 50 mol%, preferably 5 to 30 mol%. .

A material in which solid fine particles are contained in the image forming layer of the image forming material of the present invention and the surface of the solid fine particles is modified with a crosslinking group contained in the following acid crosslinking compound can be used. As the material, fine particles formed of cross-linked or uncross-linked polymethyl methacrylate, polystyrene, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyethylene terephthalate, cross-linked vinyl polymer, etc. Fine particles of silicon dioxide (eg, colloidal silica), diatomaceous earth, zinc oxide, titanium oxide, zirconium oxide, glass, alumina, dextrin, starch (eg, rice starch), calcium stearate, zinc stearate, polysaccharide fatty acid ester, polyvinyl acetate , Polyvinylidene chloride, polyethylene oxide, polyethylene glycol, polyacrylic acid, polyacrylamide, alkyl polyacrylate, polystyrene and polystyrene derivatives and these Copolymer using a monomer of the polymer, polyvinyl methyl ether, epoxy resin, fusible phenol resin, polyamide, fine particles formed by the polyvinyl butyral. As the solid fine particles, silica particles or crosslinked acrylic resin particles are preferable. The average particle size of the solid fine particles is 0.01 to 0.5
The range of μm is preferred. The average particle diameter of the solid fine particles can be measured by, for example, a diffusion type particle size distribution meter, and the peak is a value read from the data of “particle diameter-% by weight”.

The content of the acid crosslinking compound is preferably from 5 to 60% by weight, particularly preferably from 20 to 45% by weight, based on the total solid content of the composition for forming the image forming layer. One kind of the acid crosslinking compound may be used alone, or two or more kinds may be used as a mixture.

In the image forming layer of the present invention, if necessary,
Nonionic surfactants, cationic surfactants, anionic surfactants and fluorine surfactants can be contained, and if necessary, dyes, pigments, sensitizers, organic acids, and organic acids other than those described above. Bases and the like can be contained.

The image-forming material of the present invention can be produced by dissolving the components for forming the image-forming layer in a solvent, coating the solution on a suitable support surface, and drying to provide 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 and the like. No. These solvents are used alone or in combination of two or more.

As the coating method, conventionally known methods, for example, spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating, curtain coating and the like are possible. The amount of application varies depending on the application, for example,
Speaking of photosensitive lithographic printing plates, 0.5 to 0.5
5.0 g / m ² is preferred.

Examples of the support on which the image forming layer of the present invention is provided include metal plates such as aluminum, zinc, steel, and copper, and metal plates plated or vapor-deposited with chromium, zinc, copper, nickel, aluminum, iron, and the like. Examples thereof include paper, plastic films and glass plates, paper coated with resin, paper covered with metal foil such as aluminum, and plastic films subjected to hydrophilic treatment.

When the present invention is applied to a photosensitive lithographic printing plate, an aluminum plate which has been subjected to surface treatment such as graining treatment, anodic oxidation treatment and, if necessary, sealing treatment may be used as a support. preferable. A known method can be applied to these processes.

The graining method includes, for example, 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 is determined, for example, by immersing an aluminum plate in a chromic 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) to dissolve the oxide film. It is determined from the weight change measurement before and after dissolution of the coating on the plate.

Examples of the sealing treatment include boiling water treatment, steam treatment, sodium silicate treatment, dichromate aqueous solution treatment and the like. 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.

The image forming material of the present invention has a wavelength of 700 nm.
Image exposure is performed using the above light sources. 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, preferably 100 mW or more.

As the developer used for developing the image forming material of the present invention, an aqueous alkali developer is suitable. As the aqueous alkaline developer, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate,
Aqueous solutions of alkali metal salts such as sodium metasilicate, potassium metasilicate, dibasic sodium phosphate, and tribasic sodium phosphate are included. The concentration of the alkali metal salt is 0.1.
It is suitable to use in the range of 05 to 20% by weight, more preferably 0.1 to 10% by weight.

In the image forming method of the present invention, an anionic surfactant, an amphoteric surfactant or an organic solvent such as alcohol can be added to the developer as required.

As the organic solvent, propylene glycol, ethylene glycol monophenyl ether, benzyl alcohol, n-propyl alcohol and the like are useful.

[0127]

Next, the present invention will be described more specifically with reference to examples. In the following examples and comparative examples, “parts” means “parts by weight”.

Example 1 (Preparation of Support) Preparation of Support A 0.24 mm-thick aluminum plate (material: 1050, tempered H16) was degreased in a 5% aqueous sodium hydroxide solution at 60 ° C. for 1 minute. Temperature, 25 ° C., current density; 60 A / dm ² , treatment time;
The electrolytic etching was performed under the condition of 30 seconds. Then
After desmutting at 60 ° C. for 10 seconds in a 5% aqueous caustic soda solution, the temperature is reduced to 20 ° C. in a 20% sulfuric acid solution.
Anodizing treatment was performed under the following conditions: current density: 3 A / dm ² , treatment time: 1 minute, and hot water sealing treatment with hot water at 30 ° C. for 20 seconds to obtain a lithographic printing plate material support. Was produced.

(Preparation of printing plate precursor) Coating solution 1 having the following composition
Was prepared, and a dry weight of 2 g /
m ^2, and the coating was dried to obtain a printing plate precursor 1.
Drying was performed at 95 ° C. for 2 minutes.

Composition of coating solution 1 Novolak resin 1 (described below) 8.0 g Infrared absorbing dye (exemplified compound IR56) 0.5 g Cyano group-containing resin 1 (described below) 1.0 g Crystal violet 0.5 g 2-butanone 54.0 g Propylene glycol monomethyl ether 36.0 g Novolak resin 1: Formaldehyde condensate of a mixture of m-cresol, p-cresol, and phenol (60/35/5). Mw = 4000 Cyano group-containing resin 1: poly (cyanomethyl methacrylate) Mw = 12,000 (exposure, development, evaluation) The obtained printing plate precursor 1 was scanned and exposed image-wise with an infrared laser, and Konica Corporation ) 30 times with PS plate developer SDR-1 (stock solution diluted 6 times)
Developing was carried out by immersing at 20 ° C. for 20 seconds with stirring to elute the exposed portion. At that time, the amount of energy required for complete elution of the exposed portion was 150 mj / cm ² . At this time, the unexposed portion corresponding to the image portion was not dissolved by the developing treatment, and a clear image was obtained. This value was taken as the sensitivity of printing plate precursor 1. In addition, the printing plate precursor 1 having 50% halftone dots exposed on the entire surface per 1 l
When the sensitivity was measured in the same manner using the fatigue developer after the m ² treatment, it was 225 mj / cm ² .

Comparative Example 1 A printing plate precursor comparison 1 was obtained in the same manner as the printing plate precursor 1 of Example 1 except that the cyano group-containing resin 1 was omitted from the composition of the coating solution 1 of Example 1. Exposure, development, and evaluation of this printing plate precursor comparison 1 were performed in the same manner as in Example 1. As a result, an unexposed portion corresponding to an image portion was eluted by development, and only a faint image was obtained. The sensitivity is 300mj
/ Cm ² . 500 mj / cm ^{2 for} fatigue developer
Exposure did not elute the exposed part.

Example 2 A printing plate precursor was prepared in the same manner as in Example 1 except that the cyano group-containing resin 1 was removed from the composition of the coating solution 1 of Example 1 and 0.5 g of the following cyano group-containing resin 2 was added instead. 2 was obtained. Exposure, development and evaluation of the printing plate precursor ² were performed in the same manner as in Example 1. As a result, the sensitivity was 125 mj / cm ² , and the sensitivity in the fatigue developing solution was 250 mj / cm ² , and clear images were obtained. .

Cyano group-containing resin 2: 30:20:50 copolymer of methacrylonitrile, 4-hydroxyphenylmaleimide, methyl methacrylate Mw = 20,0
Example 3 Example 1 A printing plate precursor 3 was prepared in the same manner as in Example 1 except that the cyano group-containing resin 1 was removed from the composition of the coating solution 1 and 0.5 g of pyrogallol trimethylsulfonate was added instead.
I got Exposure, development and evaluation of the printing plate precursor 3 were performed in the same manner as in Example 1, and the sensitivity was 175 mj / cm.
^2. Sensitivity in the fatigue developer was 200 mj / cm ² , and clear images were obtained in both cases.

Example 4 Example 1 The composition of the coating solution 1 was prepared by removing the cyano group-containing resin 1 and replacing it with 2,3,4-tris (methylsulfoxy).
A printing plate precursor 4 was obtained in the same manner as in Example 1 except that 0.5 g of benzophenone was added. Exposure of printing plate precursor 4,
When development and evaluation were carried out in the same manner as in Example 1, the sensitivity was 150 mj / cm ² , and the sensitivity in the fatigue developer was 200 mj.
/ Cm ² , and clear images were obtained.

Example 5 The same procedure as in Example 1 was repeated except that the cyano group-containing resin 1 was removed from the composition of the coating solution 1 and the hydroxyl group of the novolak resin 1 was replaced by 20 mol%, and 1.0 g of methylsulfonated resin was added. A printing plate precursor 5 was obtained in the same manner as in Example 1. Exposure, development and evaluation of the printing plate precursor 5 were performed in the same manner as in Example 1. As a result, the sensitivity was 200 mj / cm ² , and the sensitivity in the fatigue developing solution was 250 mj / cm ² , and clear images were obtained. .

Example 6 A printing plate precursor 6 was obtained in the same manner as in Example 1 except that 0.5 g of 2,3,4-tris (methylsulfoxy) benzophenone was added to the composition of the coating solution 1 of Example 1. Was. Printing plate precursor 6
Exposure, development and evaluation were performed in the same manner as in Example 1. As a result, the sensitivity was 100 mj / cm ² , and the sensitivity in the fatigue developer was 275 mj / cm ² , and clear images were obtained.

Example 7 A printing plate precursor 7 was obtained in the same manner as in Example 1 except that the coating liquid 1 of Example 1 was replaced with the coating liquid 7 having the following composition. Exposure, development and evaluation of the printing plate precursor 7 were performed in the same manner as in Example 1. As a result, the sensitivity was 250 mj / cm ² , and the sensitivity in the fatigue developing solution was 250 mj / cm ² , and clear images were obtained. .

Composition of Coating Solution 7 Novolak Resin 1 (described above) 8.0 g Ketal Compound 1 (described below) 2.0 g 1,3-bis (trichloromethyl) -5-methyl-s-triazine 0.1 g Infrared absorbing dye ( Exemplified compound IR56) 0.1 g Cyano group-containing resin 2 (described above) 1.0 g 2-butanone 54.0 g

[0139]

Embedded image

Example 8 A printing plate precursor 8 was obtained in the same manner as in Example 1 except that the coating liquid 1 of Example 1 was replaced with the coating liquid 8 having the following composition. After the same exposure as in Example 1 for the printing plate precursor 8 and 150 before development,
The evaluation was performed in the same manner as in Example 1 except that the heat treatment was performed at 2 ° C. for 2 minutes. The sensitivity was 225 mj / cm ² and the sensitivity in the fatigue developer was 400 mj / cm ² , and clear images were obtained. Was done.

Composition of Coating Liquid 8 Novolak Resin 1 (described above) 8.0 g Ketal Compound 1 (described above) 2.0 g 1,3-bis (trichloromethyl) -5-methyl-s-triazine 0.1 g Infrared absorbing dye ( Exemplified compound IR56) 0.1 g Cyano group-containing resin 2 (described above) 1.0 g 2-butanone 54.0 g Propylene glycol monomethyl ether 36.0 g

[0142]

According to the present invention, there is provided an image forming material which is highly sensitive to infrared light, does not require heat treatment after exposure, is less susceptible to fluctuations in development conditions, and is suitable for a large amount of development processing. can get. Further, according to the present invention, a lithographic plate which is highly sensitive to infrared light, does not require heat treatment after exposure, is less susceptible to fluctuations in development conditions, is suitable for a large amount of development processing, and has excellent printing durability An image forming material suitable for producing a printing plate is obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03F 7/32 G03F 7/32 F-term (Reference) 2H025 AA01 AA04 AA12 AB03 AC08 AD01 AD03 BE00 BE08 BE10 CB08 CB13 CB14 CB15 CB29 CB41 CC11 CC13 CC17 CC20 DA36 FA10 FA17 2H096 AA06 BA06 BA11 EA04 EA23 GA08 2H114 AA04 BA02 DA31 DA35 DA47 DA56 DA59 EA03 GA05

Claims (13)

[Claims] 1. An image forming layer comprising a novolak resin, an infrared absorber, and a cyano group-containing resin containing a repeating structural unit represented by the following general formula (1) on a support. Image forming material. Embedded image [Wherein, X represents an alkylene group or an arylene group;
Represents 0 or 1, Y represents -COO- or -CONH-, n represents 0 or 1, R ₁ represents a hydrogen atom, an alkyl group, a hydroxyalkyl group, an alkoxyalkyl group or a halogenated alkyl group Represent. ] 2. An image-forming material comprising, on a support, an image-forming layer whose solubility in an alkaline aqueous developer changes in an exposed portion by imagewise scanning exposure with infrared laser light. Contains a novolak resin and a cyano group-containing resin containing a repeating structural unit represented by the following general formula (1). Embedded image [Wherein, X represents an alkylene group or an arylene group;
Represents 0 or 1, Y represents -COO- or -CONH-, n represents 0 or 1, R ₁ represents a hydrogen atom, an alkyl group, a hydroxyalkyl group, an alkoxyalkyl group or a halogenated alkyl group Represent. ] 3. The repeating structural unit represented by the general formula (1) is represented by the following general formula (2).
Or the image forming material according to 2. Embedded image [In the formula, R ₂ represents an alkyl group, a hydroxyalkyl group, an alkoxyalkyl group or a halogenated alkyl group. ] 4. An image forming layer comprising a compound having a plurality of aromatic OH groups, wherein a part or all of the aromatic OH groups are substituted with a substituent having a structure represented by the following general formula (3). 4. The image forming material according to claim 1, wherein the image forming material is contained. Formula ₍₃₎ R ₃ -SO ₂ -O- wherein, R ₃ represents an alkyl group, an alkenyl group, a cycloalkyl group, phenyl or alkyl-substituted phenyl group. ] 5. A substituent having a structure represented by the following general formula (3), wherein a part or all of the aromatic OH group of a compound having a plurality of aromatic OH groups is provided on a support. An image forming material comprising a sulfonic acid ester compound substituted with: Formula ₍₃₎ R ₃ -SO ₂ -O- wherein, R ₃ represents an alkyl group, an alkenyl group, a cycloalkyl group, phenyl or alkyl-substituted phenyl group. ] 6. An image-forming material having an image-forming layer on a support, wherein the solubility of the exposed portion in an alkaline aqueous developer is changed by imagewise scanning exposure with an infrared laser beam. Is a novolak resin and an aromatic O
An image-forming material comprising a sulfonic acid ester compound in which a part or all of the aromatic OH group of a compound having a plurality of H groups is substituted with a substituent having a structure represented by the following general formula (3). Formula ₍₃₎ R ₃ -SO ₂ -O- wherein, R ₃ represents an alkyl group, an alkenyl group, a cycloalkyl group, phenyl or alkyl-substituted phenyl group. ] 7. The image forming material according to claim 4, wherein the compound having a plurality of aromatic OH groups is pyrogallol. 8. The image forming material according to claim 4, wherein the compound having a plurality of aromatic OH groups is polyhydroxybenzophenone. 9. The compound according to any one of claims 4 to 6, wherein the compound having a plurality of aromatic OH groups is a compound having a structural unit represented by the following general formula (4) in the molecule. The image forming material as described in the above. Embedded image [In the formula, R ₄ represents a hydrogen atom or an alkyl group having 1 to 9 carbon atoms. R ₅ represents a hydrogen atom or a methyl group. R ₆ represents a hydrogen atom, a methyl group, an ethyl group, an n-propyl group,
-Represents a propyl group or a phenyl group. a represents an integer of 1 to 3. ] 10. The image forming layer according to claim 1, wherein the image forming layer contains a compound that generates an acid by being decomposed and a compound that is decomposed by the presence of the acid. Image forming materials. 11. The image forming layer according to claim 1, wherein the image forming layer contains a compound that generates an acid by being decomposed and a compound that is cross-linked by the presence of the acid. Image forming materials. 12. The image forming material according to claim 1, wherein the surface of the support on the side on which the image forming layer is provided is hydrophilic. 13. An image forming material according to any one of claims 1 to 12, which is image-wise scan-exposed with an infrared laser beam, and then a non-image portion is eluted and removed with an alkaline aqueous developer. Characteristic image forming method.