JPH03225343A - Photosensitive composition - Google Patents

Abstract

PURPOSE:To enhance printing resistance by incorporating a novolak resin containing <= 5 wt.% phenols and a halomethyloxadiazole compound to be allowed to produce free halogen radicals by irradiation with active rays and a discororing agent. CONSTITUTION:The novolak resin is reduced in the content of the excess phenols used for synthesizing the resin to <= 5 wt.% after the synthesis by heating. The novolak resin has a weight average molecular weight Mw of 2.0X10<3> - 2.0X10<4>, and a number average molecular weight Mn of 7.0X10<2> - 5.0X10<3>, and the novolak resin containing the <= 5 wt.% phenols is contained in an amount of 50 - 90 wt.% of the photosensitive composition, and the halomethyldioxazole compound to be allowed to produce free halogen radicals by irradiation with active rays is contained in the photosensitive composition in an amount of 0.2 - 10 wt.%, and the discororing agent mutually reacting with the halogen free radicals produced by irradiation with the active rays and changing its tone is contained in an amount of 0.02 - 5 wt.% of the photosensitive composition, thus permitting high sensitivity and superior visualizability by exposure to light.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a photosensitive composition used in a photosensitive lithographic printing plate, and more particularly to a photosensitive composition containing a novolac resin as an alkali-soluble resin. be.

[Prior Art] Usually, the photosensitive layer of a positive photosensitive lithographic printing plate contains a quinonediazide compound as a photosensitive substance and an alkali-soluble resin as a component for increasing film strength and alkali solubility. . In particular, as the alkali-soluble resin, novolac resin is generally used from the viewpoint of strength of the image area, oil sensitivity, abrasion resistance, etc.

[Problems to be Solved by the Invention] However, since novolac resins are usually obtained by condensing phenols and formaldehyde in the presence of an acid catalyst, residual components of phenols such as cresol are inevitably present in the resin. As a result, environmental problems such as odor caused by the residual components have arisen in processes such as coating solution preparation, coating of photosensitive lithographic printing plates, and drying.

In order to solve this problem, attempts have been made to remove the phenols remaining in the novolac resin, but although this improves the odor problem, it reduces the sensitivity of the resulting photosensitive lithographic printing plate. In addition, there have been problems in that the exposed image quality is deteriorated and the printing durability is also reduced. Here, exposure visibility refers to the ability to easily align film originals, such as when performing so-called "multi-sided printing," in which multiple film originals are printed one after another on a photosensitive planographic printing plate in different positions. Therefore, it refers to the distinguishability when a visible image is formed on a photosensitive planographic printing plate by exposure in order to make it possible to distinguish exposed areas from unexposed areas.

Therefore, an object of the present invention is to improve the odor caused by the novolak resin in a photosensitive composition using a novolak resin as an alkali-soluble resin without reducing the sensitivity and exposure visible imageability of the resulting photosensitive lithographic printing plate. The object of the present invention is to provide a photosensitive composition that can be used as a photosensitive composition.

Another object of the present invention is to provide a photosensitive composition suitable for a photosensitive lithographic printing plate having excellent printing durability.

[Means for Solving the Problems] In view of the above problems, the present inventors have conducted extensive research, and as a result, the above object of the present invention is to provide (a) a 1,2-naphthoquinone-2-diazide-4-sulfonic acid ester compound. , (b) 5% by weight
Novolak resins containing less than phenolics and (c
) Methyloxadiazole compound and/or halomethyl S that generates halogen free radicals by irradiation with actinic rays
- a triazine compound; and (d) a color change agent that changes its color tone by interacting with the halogen free radicals.

The present invention will be explained in more detail below.

The novolak resin used in the present invention is a resin obtained by condensing phenols and formaldehyde in the presence of an acid catalyst. Examples of the phenols include phenol, 0-cresol, -1-cresol, p-cresol, , 3,5-xylenol, 2,4-xylenol, 2
, 5-xylenol, carvacrol, thymol, catechol, resorcinol, hydroquinone, pyrogallol, 7
Examples include glucine. The above phenols can be used alone or in combination with formaldehyde to obtain a resin. Among these, preferred novolac resins are resins obtained by copolycondensing formaldehyde with at least one selected from phenol, -1-cresol (or 0-cresol), and p-cresol, such as phenol-formaldehyde resin. ,
m-cresol/formaldehyde resin, 0-cresol/formaldehyde resin, phenol/p-cresol/formaldehyde copolymer resin, -1-cresol/formaldehyde resin
Examples include p-cresol/formaldehydose sol/formaldehyde copolycondensate resin, phenol/-monocresol/p-cresol/formaldehyde copolycondensate resin, and phenol/〇-cresol/p-cresol/formaldehyde copolycondensate resin. Furthermore, among the above novolac resins, phenol-
Mono-cresol/p-cresol/formaldehyde resins are preferred.

The novolac resin used in the present invention contains less than 5% by weight of phenols used for synthesis, preferably 3.5% by weight.
Although it contains no more than 3% by weight, more preferably no more than 3% by weight, such a novolak resin can be prepared by, for example, heating under reduced pressure after synthesis.

In the present invention, the above novolac resins may be used alone or in combination of two or more.

The molecular weight of the novolak resin (polystyrene standard) is a weight average molecular weight MW of 2.0 x 103 to 2.0 x
10 Gin, number average molecular weight Mn is 7, OX102-5. O
The value is preferably within the range of X103, and more preferably, IVIW is 3. OXi 03 ~6. OX1
Q3, Mn is 7.7x 102 ~ 1, 2x103
The value is within the range of . The molecular weight of the novolak resin in the present invention is measured by GPC (gel permeation chromatography).

The novolac resin containing less than 5% by weight of phenols is preferably contained in the photosensitive composition of the present invention in an amount of 30 to 95% by weight, preferably 50 to 90% by weight.

In the present invention, various alkali-soluble resins other than the above-mentioned novolac resins can be contained within a range that does not impair the purpose of the present invention. Examples of the resins used include vinyl polymers having phenolic hydroxyl groups and/or carboxyl groups, and urethane resins having carboxyl groups.

As vinyl polymers having phenolic hydroxyl groups,
Preferably used are polymers formed by polymerization by cleavage of carbon-carbon double bonds and containing at least one structural unit of the following general formulas [I] to [VI].

General formula [I] +CR+ R2-CRa + 〇-Co-B-Of-1 General formula [I[] +CR+ R2-CR3+ 〇〇NR+-+A+f-B-OH General formula [I[[] % formula% General formula [rV] +CR1R2-CR3→- -0H General formula [V] H General formula [VI] H In the formula, R1 and R2 each represent a hydrogen atom, an alkyl group, or a carboxyl group, preferably a hydrogen atom. R3 represents a hydrogen atom, a halogen atom, or an alkyl group, preferably a hydrogen atom or an alkyl group such as a methyl group or an ethyl group. R4 is a hydrogen atom, an alkyl group,
Represents an aryl group or an aralkyl group, preferably a hydrogen atom. A represents an alkylene group that may have a substituent that connects a nitrogen atom or an oxygen atom and an aromatic carbon atom, m represents an integer of 0 to 10, and B represents a phenylene group that may have a substituent. Represents a naphthylene group which may have a group or a substituent. In the present invention, among these, a copolymer containing at least one structural unit represented by the general formula [II] is preferred.

The vinyl polymer preferably has a copolymer-type structure, and in such a copolymer, at least one structural unit represented by each of the general formulas [I] to [VI] Monomeric units that can be used in combination with, for example, ethylenically unsaturated olefins such as ethylene, propylene, isobutylene, butadiene, isoprene, etc., such as styrene, α-methylstyrene,
Styrenes such as p-methylstyrene and p-chlorostyrene, acrylic acids such as acrylic acid and methacrylic acid, unsaturated aliphatic dicarboxylic acids such as itaconic acid, maleic acid, and maleic anhydride, such as methyl acrylate, acrylic ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, 12-chloroethyl acrylate, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate,
Esters of α-methylene aliphatic monocarboxylic acids such as ethyl ethacrylate, nitriles such as acrylonitrile and methacrylonitrile, amides such as acrylamide, such as acrylanilide, p-chloroacrylanilide, -m:troacrylanilide , anilides such as -methoxyacrylanilide, vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, vinyl butyrate, such as methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether,
Vinyl ethers such as β-chloroethyl vinyl ether, vinyl chloride, nylidene chloride, vinylidene cyanide, such as 1-methyl-1-methoxyethylene, 1
．． Ethylene derivatives such as 1-dimethoxyethylene, 1,2-dimethoxyethylene, 1,1-dimethoxycarbonylethylene 1-nitroethylene, such as N-
There are vinyl monomers such as N-vinyl compounds such as vinylpyrrole, N-vinylcarbazole, N-vinylindole, N-vinylvirolone, and N-vinylpyrrolidone. These vinyl monomers exist in polymer compounds with a structure in which unsaturated double bonds are cleaved.

Among the above monomers, those used in combination with at least one of the structural units represented by bottom [I] to [VI] include (meth)acrylic acids, esters of aliphatic monocarboxylic acids, and nitriles. shows excellent overall performance and is preferable. More preferred are methacrylic acid, methyl methacrylate, acrylonitrile, ethyl acrylate, and the like.

These monomers may be bonded to the vinyl polymer in either a block or random manner.

In the vinyl polymer, -bottom [I] to [VT
] The content of the structural units shown in each is 5 to 70
It is preferably mol %, particularly preferably 10 to 40 mol %.

Typical examples of vinyl polymers used in the present invention are listed below. In addition, in the compounds exemplified below, ly
lw is the weight average molecular weight, Mn is the number average molecular weight, s,
1, o, m and n are each exemplary compound CH.

(g) CH.

(j) CH3 ■ (k) CH.

(-) CH.

Examples of vinyl copolymers having a carboxyl group include acrylic acids such as acrylic acid and methacrylic acid; unsaturated aliphatic dicarboxylic acids such as itaconic acid, maleic acid, and maleic anhydride; Examples include vinyl copolymers synthesized using polymer components as essential components. In the copolymer, monomer components having carboxyl groups include, for example, ethylene,
Ethylenically unsaturated olefins such as propylene, isobutylene, butadiene, isoprene; e.g. styrene, α
- Styrenes such as methylstyrene, p-methylstyrene, p-chlorostyrene; e.g. methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, 2-chloroethyl acrylate, phenyl acrylate , esters of α-methylene aliphatic monocarboxylic acids such as methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, and ethyl ethacrylate; Nitriles such as acrylonitrile and methacrylonitrile; Amides such as acrylamide: For example, imides such as N-phenylmaleimide; for example, acrylanilide, p-chloroacrylanilide,
-m: Anilides such as troacrylanilide and m-methoxyacrylanilide; For example, vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, and vinyl butyrate; For example, methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, β-chloro Vinyl ethers such as ethyl vinyl ether: Vinyl chloride:
Vinylidene chloride: Vinylidene cyanide; for example, ethylene such as 1-methyl-1-methoxyethylene, 1.1-dimethoxyethylene, 1.2-dimethoxyethylene, 1.1-dimethoxycarbonylethylene, 1-methyl-1-nitroethylene, etc. Derivatives; for example, N-vinylpyrrole, N-vinylcarbazole, N-vinylindole, N-vinylvirolone, N-vinylpyrrolidone, etc.
-Vinyl monomers such as -vinyl compounds are preferred. These vinyl monomers exist in polymer compounds with a structure in which unsaturated double bonds are cleaved.

In the present invention, among the above monomers, esters of aliphatic monocarboxylic acids and nitriles are particularly preferably used.

These monomers may be bound in the above-mentioned polymer compound in either a block or random manner.

In addition, as a urethane resin having a carboxyl group,
Preferred examples include polyurethane resins whose basic skeleton is a reaction product of a diisocyanate compound represented by the following general formula (A) and a diol compound having a carboxyl group represented by the general formula (B) or (c).

0CN-R+ -NGO(A) HO-Ra Ar -R4-OHR5(c) OOH In the formula, R1 represents a divalent aliphatic or aromatic hydrocarbon which may have a substituent. If necessary, other functional groups that do not react with isocyanate groups in R1, such as esters,
It may have a urethane, amide, or ureido group.

R2 is a hydrogen atom, alkyl which may have a substituent,
Aralkyl, aryl, alkoxy, aryloxy 8
group, preferably a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 6 to 15 carbon atoms. Ra
, R4 and R5 may be the same or different, and represent a single bond, a divalent aliphatic group which may have a substituent, or an aromatic hydrocarbon group. Preferably carbon number 1-20
alkylene group, arylene group having 6 to 15 carbon atoms,
More preferably, it represents an alkylene group having 1 to 8 carbon atoms.

Further, if necessary, R3, R4 and R5 may contain other functional groups that do not react with isocyanate groups, such as eight groups such as ester, urethane, amide, ureido, and ether.

In addition, two or three of R2, R3, R4 and R5
may form a ring.

Ar represents a trivalent aromatic hydrocarbon group which may have a substituent, preferably an aromatic group having 6 to 15 carbon atoms.

Specifically, the diisocyanate compound represented by the general formula (A) includes 2,4-tolylene diisocyanate, 2
．． Dimer of 4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-xylylene diisocyanate, metaxylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, 3,3'- dimethyl-biphenyl 4
．． Aromatic diisocyanate compounds such as 4'diisocyanate; aliphatic diisocyanate compounds such as hexamethylene diisocyanate, trimethyl hexamethylene diisocyanate, lysine diisocyanate, dimer acid diisocyanate, etc.; isophorone diisocyanate, 4,4'-methylene bis(cyclohexyl isocyanate), methylcyclohexane-2,4 (or 2.6)
Diisocyanate, 1,3-(methyl isocyanate)
Alicyclic diisocyanate compounds such as cyclohexane; diisocyanate compounds which are reaction products of diol and diisocyanate such as an adduct of 1 mol of 1,3-butylene glycol and 2 mol of tolylene diisocyanate; and the like.

In addition, the diol compound having a carboxyl group represented by bottom (B) or (c) is specifically 3,5-
Dihydroxybenzoic acid, 2,2 bis(hydroxymethyl)propion 89.2. 2bis(hydroxyethyl)
Propionic acid, 2゜2-bis(3-hydroxypropyl)propionic acid, 2.2-bis(hydroxymethyl)acetic acid, bis-(4-hydroxyphenyl)acetic acid, 4.4bis-(4-hydroxyphenyl)pentane Examples include acid, tartaric acid, and the like.

The polyurethane resin may be formed from a diisocyanate compound represented by the general formula (A) and two or more diol compounds having a carboxyl group represented by the general formula (B) or (c).

In the present invention, an alkali-soluble resin other than the novolac resin of the present invention is contained in the photosensitive composition, for example, at a concentration of 2 to 80%.
Contains % by weight.

1,2-naphthoquinone-2-diazide in the present invention
Various known compounds can be used as the 4-sulfonic acid ester compound (hereinafter referred to as "the quinonediazide compound of the present invention"), but in particular 1.2-naphthoquinone-2-diazide-4-sulfonic acid and phenols. and ester compounds of aldehydes or ketones with polycondensation resins are preferably used.

Examples of the phenols include phenol, 0-
Cresol, -mono-cresol, p-cresol, 3,5
- Monohydric phenols such as xylenol, carvacrol, and thymol, dihydric phenols such as catechol, resorcinol, and hydroquinone, and trihydric phenols such as pyrogallol and 70-glucine. Examples of the aldehyde include formaldehyde, benzaldehyde, acetaldehyde, crotonaldehyde, and furfural. Preferred among these are formaldehyde and benzaldehyde. Further, examples of the ketone include acetone, methyl ethyl ketone, and the like.

Specific examples of the polycondensation resin include phenol/formaldehyde resin, m-cresol/formaldehyde resin, p-cresol/formaldehyde resin, I-
, p-mixed cresol/formaldehyde resin, resorcinol/benzaldehyde resin, pyrogallol/acetone resin, and the like.

O of the phenols of the quinonediazide compound of the present invention
1,2-naphthoquinone-2-diazide-4 for H group
- The condensation rate of sulfonic acid (reaction rate for one OH group) is preferably 15 to 80%, more preferably 20 to 60%.
%.

Further, as the quinonediazide compound of the present invention, the polyhydroxy compound 1,2-naphthoquinone-2-diazide-4
Examples of such compounds include cyclohexyl 1°2-naphthoquinonediazide-4-sulfonic acid ester, 1-(1,
2-naphthoquinonediazide-4-sulfonyl)-3,5
-dimethylpyrazole, 1,2-naphthoquinonediazide-4-sulfonic acid-4″-hydroxydiphenyl-4″
-Azo-β-naphthol ester, 2'(1,2-naphthoquinonediazide-4-sulfonyloxy)-1-hydroxy-anthraquinone, 1,2-naphthoquinonediazide-4-sulfonic acid-2,4-dihydroxybenzophenone ester, 1.2-naphthoquinonediazide-4-sulfonic acid-2,3,4-trihydroxybenzophenone ester, 1,2-naphthoquinonediazide-4-sulfonic acid-2,3,4',4'-tetrahydroxybenzophenone ester, 1.2-naphthoquinonediazide-
A condensate of 2 moles of 4-sulfonic acid chloride and 1 mole of 4°4'-dihydroxy-1,1'-diphenylsulfone,
Examples include a condensate of 1 mol of 1,2-naphthoquinonediazide-4-sulfonic acid chloride and 21 mol of purpurogasa.

In addition, 1.2 of polyurethane resin as shown below
-naphthoquinone-2-diazide-4-suυ (where n represents an integer from 2 to 300.

) Further, as the quinonediazide compound of the present invention, an ester compound of a vinyl polymer having a phenolic hydroxyl group and 1°2-naphthoquinone-2-diazide-4-sulfonic acid can also be used.

The vinyl polymer having a phenolic hydroxyl group that forms such an ester compound is a polymer having a unit having a phenolic hydroxyl group in its molecular structure, and preferably a vinyl polymer having a phenolic hydroxyl group that is used as the alkali-soluble resin. A material similar to a vinyl polymer can be used.

As the quinonediazide compound of the present invention, each of the above compounds may be used alone, or two or more thereof may be used in combination. The proportion of the quinonediazide compound of the present invention in the photosensitive composition of the present invention is preferably 5 to 601% by weight, particularly preferably 10 to 50% by weight.

The halomethyloxadiazole compounds that generate halogen free radicals upon irradiation with actinic rays used in the present invention include:
Preferably, a compound represented by the following general formula [VI'] is used.

General formula [] (wherein, Xa is a trihaloalkyl group having 1 to 3 carbon atoms, L is a hydrogen atom or a methyl group, J is a substituted or unsubstituted aryl group or a heterocyclic group, and n is 011 or 2 ) Specifically, the compounds represented by the general formula [■] include oxadiazole compounds having a benzofuran ring such as;
2-trichloromethyl-5-(p-methoxysdyryl)-1, which is described in JP-A-54-74728,
3,4-oxadiazole compound or the following compound described in JP-A-60-241049: The following compound described in JP-A-54-74728: The following compound described in JP-A-55-77742: 1986
The following compound described in Publication No.-3626: JP-A-60-17
The following compound described in Publication No. 7340: JP-A-61-143
Examples include the following compounds described in Japanese Patent No. 748.

The amount of the halomethyloxadiazole compound that generates halogen free radicals upon irradiation with actinic rays contained in the photosensitive composition is preferably 0.01 to 20% by weight, more preferably 0.1 to 20111%, particularly Preferably 0.2~
It is 10% by weight.

As the halomethyl 5-)-lyazine compound which generates halogen free radicals upon irradiation with actinic rays used in the present invention, for example, a compound represented by the following bottom [■] is preferably used.

a (wherein xa is a trihaloalkyl group having 1 to 3 carbon atoms, B' is a hydrogen atom or a methyl group, A' is a substituted or unsubstituted aryl group or a heterocyclic group, and n is 01
1 or 2. ) Specific examples of the compound represented by the above - bottom [■] include 2,4-bis-(trichloromethyl) described in JP-A-53-36223;
-6-p-methoxystyryl-8-triazine compound,
Examples include 2<4>-bis-(trichloromethyl)-6-1)-dimethylaminostyryl-S-triazine compound.

The amount of the halomethyl S-triazine compound contained in the total photosensitive composition is 0.01 to 20% by weight, more preferably 0.1 to 20% by weight, particularly preferably 0.2 to 10% by weight. .

In the present invention, the color changing agent that changes the color tone by interacting with the halogen free radicals generated by irradiating the halomethyl oxadiazole compound or halomethyl s-triazine compound with actinic rays includes those that develop color and those that fade or change color. There are two types: As the color-changing agent that causes fading or discoloration, various dyes such as diphenylmethane, triphenylmethane-based thiazine, oxazine-based, xanthine-based, anthraquinone-based, iminonaphthoquinone-based, and azomethine-based dyes are effectively used.

Specific examples of these include the following: Brilliant Green, Eosin, Ethyl Violet, Erythrosin B1 Methyl Green, Crystal Violet, Pesic Tsuksin, Phenolphthalein, 1,3-Diphenyltriazine, Alizarin Red S1 Thymolphthalein, Methyl Violet 2B,
Quinaldine Red, Rose Bengal, Metanyl Yellow Thymol Sulfophthalein, Xylenol Blue Methyl Orange, Orange ■, Diphenylthiocarbazone, 2
．． 7-dichlorofluorescein, rose methyl red, Congo red, benzobrulin 4B, α-naphthyl red, Nile blue 2B, Nile blue A1 phenacetaline, methyl violet, malachite green, rose tuxin, Victoria Pure Blue Boil (manufactured by Hodogaya Chemical), Oil Blue #603 [manufactured by Orient Chemical Industry ■], Oil Pink #312 [manufactured by Orient Chemical Industry ■], Oil Red 5B [manufactured by Orient Chemical Industry ■], Oil Blue Let #308 [manufactured by Orient Chemical Industry ■], Oil Red OG [manufactured by Orient Chemical Industry ■]
, Oil Red RR [manufactured by Orient Chemical Industry ■], Oil Green #502 [manufactured by Orient Chemical Industry ■], Spiron Red BEH Special [manufactured by Hodogaya Chemical Industry ■],
m-cresol purple, cresol red, rhodamine B10-damine 6G, fast acid violet R1 sulforhodamine B1 auramine, 4-D-diethylaminophenylimino naphthoquinone, 2-carboxyanilino-4-p-diethylaminophenylimino naphthoquinone, 2-carbo Stearylamino-4-p-dihydroxyethylamino-phenylimino naphthoquinone, p-methoxybenzoyl-p'-diethylamino 0
'-Methylphenyliminoacetanilide, cyano-p
-diethylaminophenyliminoacetanilide, 1-
Phenyl-3-methyl-4-p-diethylaminophenylimino-5-pyrazolone, 1-β-naphthyl-4-p
-diethylaminophenylimino-5-pyrazolone.

Moreover, arylamines can be mentioned as color-changing agents that develop color. Arylamines suitable for this purpose include not only simple arylamines such as primary and secondary aromatic amines, but also so-called leuco dyes, examples of which include the following.

Diphenylamine, dibenzylaniline, triphenylamine, diethylaniline, diphenyl°p-phenylenediamine, p-1-luidine, 4°4'-biphenyldiamine, 0-chloroaniline, 0-bromoaniline,
4-chloro-〇-phenylenediamine, O-bromo-N
, N-dimethylaniline, 1,2,3-triphenylguanidine, naphthylamine, diaminodiphenylmethane, aniline, 2,5-dichloroaniline, N-methyldiphenylamine, 0-toluidine, p,p'-tetramethyldiaminodiphenylmethane, N , N-dimethyl-
p-phenylenediamine, 1,2-dianilinoethylene, p,p',p''-hexamethyltriaminotriphenylmethane, p,p'-tetramethyldiaminotriphenylmethane, p.

p'-tetramethyldiaminodiphenylmethylimine,
p, 1. p"-triamino-0-methyltriphenylmethane, p, p', p"-triaminotriphenylcarbinolmethylaminodiphenyl-4-anilinonaphthylmethane, p. p'. p“-triaminotriphenylmethane, p
, p', p''-hexapropyltriaminotriphenylmethane.

In the present invention, among the above-mentioned color change agents, dyes that can change color in a pH range of 1 to 5 are preferred.

The proportion of the above color changing agent in the photosensitive composition is 0,0
It is preferably used in an amount of 1 to 10% by weight, more preferably 0.02 to 5% by weight.

Further, the photosensitive composition of the present invention can preferably contain an organic acid or acid anhydride.

As the organic acid used in the present invention, all known various organic acids can be used, but organic acids having a pKa value of 2 or more are preferable, and those having a pKa value of 3.0 to 9.0 are more preferable, and particularly preferable. An organic acid having a molecular weight of 3.5 to 8.0 is used. However, the pKa value used in the present invention is a value at 25°C.

Such organic acids include, for example, the Basics of Chemistry Handbook ■ (
Maruzen■1966. Among the organic acids described on pages 1054 to 1058), all compounds that can exhibit the pKa value of the present invention can be mentioned. Examples of such compounds include benzoic acid, adipic acid, azelaic acid, isophthalic acid, p-toluic acid, q-toluic acid, β-ethylglutaric acid, m-oxybenzoic acid, p-oxybenzoic acid, 3, 5-dimethylbenzoic acid, 3,4-dimethoxybenzoic acid, glyceric acid, glutaconic acid, glutaric acid,
p-anisic acid, succinic acid, sebacic acid, β,β-diethylglutaric acid, 1,1-cyclobutanedicarboxylic acid, 1
, 3-cyclobutanedicarboxylic acid, 1.

1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, β,β-dimethylglutaric acid, dimethylmalonic acid,
α-tartaric acid, speric acid, terephthalic acid, pimelic acid,
Phthalic acid, fumaric acid, β-propylglutaric acid, propylmalonic acid, mandelic acid, mesotartaric acid, β-methylglutaric acid, β,β-methylpropylglutaric acid, methylmalonic acid, malic acid, 1,1-cyclohexanedicarboxylic acid Acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, cis-4-cyclohexene-1,2-dicarboxylic acid, erucic acid, undecenoic acid, lauric acid, n-
Capric acid, pelargonic acid, n-undecanoic acid and the like can be mentioned. Other organic acids having an enol structure such as Meldrum's acid and ascorbic acid can also be preferably used. The proportion of the above organic acid in the photosensitive layer is 0.
．． 05 to 10% by weight is appropriate, preferably 0.1 to 10% by weight.
It is 5% by weight.

Further, as the acid anhydride used in the present invention, all known various acid anhydrides can be used, but cyclic acid anhydrides are preferable, such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, etc. phthalic acid,
3.6-Nindooxy-∆imaichi tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, glutaric anhydride, maleic anhydride, lyol maleic anhydride, α-phenyl maleic anhydride, succinic anhydride, pyromellitic acid, etc. It will be done. These acid anhydrides are preferably contained in the photosensitive layer in an amount of 0.05 to 10% by weight, particularly 0.1 to 5% by weight.

The photosensitive composition of the present invention preferably has the following general formula [IX]
It includes a condensation resin of substituted phenols and aldehydes represented by and/or an 0-naphthoquinonediazide sulfonic acid ester compound of the resin.

(In the formula, R5 and R6 each represent a hydrogen atom, an alkyl group, or a halogen atom, and R7 represents an alkyl group or a cycloalkyl group having 2 or more carbon atoms.) Substituted phenols represented by the above general formula [IX] , R5 and R6 are a hydrogen atom, an alkyl group (1
It includes those containing from 3 to 3 carbon atoms. C1 -C2 alkyl groups are particularly useful. ) or a halogen atom (among fluorine, chlorine, bromine and iodine atoms, chlorine and bromine atoms are particularly preferred), and R7 represents an alkyl group having 2 or more carbon atoms (preferably 15 or less carbon atoms). , C 3 -C 8 alkyl groups are particularly useful) or C cycloalkyl groups (including those containing 3 to 15 carbon atoms), C 3 -C 8 alkyl groups are particularly useful. ).

Examples of the substituted phenols include isopropylphenol, tert-butylphenol, tert-amylphenol, hexylphenol, tert-octylphenol, cyclohexylphenol, 3-methyl-
4-chloro-5-tert-butylphenol, isopropylcresol, tert-butylcresol, te
rt-amyl cresol, hexyl cresol, ter
Examples include t-octylcresol and cyclohexylcresol, among which tert-octylphenol and tert-butylphenol are particularly preferred.

Examples of the aldehydes include aliphatic and aromatic aldehydes such as formaldehyde, benzaldehyde, acetaldehyde, acrolein, crotonaldehyde, and furfural, including those having 1 to 6 carbon atoms. Among them, formaldehyde and benzaldehyde are preferred.

The resin in which the substituted phenol and aldehyde are condensed in the present invention is synthesized by polycondensing the substituted phenol represented by -bottom [IX] and the aldehyde in the presence of an acidic catalyst. Inorganic acids and organic acids such as hydrochloric acid, oxalic acid, sulfuric acid, and phosphoric acid are used as acidic catalysts, and the blending ratio of substituted phenols and aldehydes is as follows:
0.7 aldehydes per 1 mole part of substituted phenols
~1.0 mole part is used. Alcohols, acetone, water, tetrahydrofuran, etc. are used as the reaction solvent.

After reaction at a predetermined temperature (-5 to 120°C) for a predetermined time (3 to 48 hours), heat under reduced pressure, wash with water, and dehydrate.
Alternatively, the reactant can be obtained by precipitating water.

The O-naphthoquinonediazide sulfonic acid ester compound of the polymerized resin of substituted phenols and aldehydes of the present invention can be prepared by dissolving the condensed resin in a suitable solvent, such as dioxane, and adding O-naphthoquinonediazide sulfonic acid chloride to the solution. is added, and an alkali such as an alkali carbonate is added dropwise to the equivalence point while heating and stirring to esterify the product.

In the esterified product, the condensation rate of 0-naphthoquinonediazide sulfonic acid chloride with respect to the hydroxyl group of the phenol (reaction rate % with respect to one hydroxyl group) is 5 to 80%.
is preferable, more preferably 20 to 70%, still more preferably 30 to 60%. The condensation rate is calculated by determining the content of sulfur atoms in the sulfonyl group by elemental analysis.

The resin in which the substituted phenol represented by the above-mentioned bottom [IX] and the aldehyde are condensed and the 0-naphthoquinonediazide sulfonic acid ester compound of the resin occupying in the photosensitive composition of the present invention is 0.05 -15% by weight is preferred, particularly preferably 1-10% by weight, and the weighted average molecular weight MW is preferably 5.0X102-5.0X1
Q3 range, more preferably 7.0XIQ2-3
．． The range is 0x103. Its number average molecular weight Mn is 3
, OXlQ is preferably in the range of 2 to 2.5X103, more preferably 4.0X1Q2 to 2.0X
The range is 103.

The above molecular weight is measured by GPC method.

Calculation of number average molecular weight Mn and weighted average molecular weight MW is described in Morio Tsuge, Tatsuya Miyabayashi, and Masayuki Tanaka, “Journal of the Chemical Society of Japan” 80.
The test shall be carried out by the method described on pages 0 to 805 (1972), in which the peaks of the oligomer region are leveled (the centers of the peaks and valleys are connected).

The photosensitive composition of the present invention can also contain a compound having at least one of the following structural units [D] and [E] in its molecular structure.

Structural unit [D] 6CH2CH2O+- Structural unit [E] CH3 f-CH2CH-0k- (In the formula, n represents an integer from 2 to 5000.) The structural units [D] and [E] used in the present invention Any compound having at least one of the above structural units [D] and [E] may be used as long as it has one or both of the structural units [D] and [E], but in particular, 0 is an integer within the range of 2 to 5000. , and a boiling point of 240°C or higher, more preferably a compound where n is an integer in the range of 2 to 500 and a boiling point of 280°C or higher, and most preferred is a compound where n is 3 to 100. Compounds within the range of

Examples of such compounds include: ・Polyethylene glycol (HO-4CH2CH,O
")"rrH)・Polyoxyethylene alkyl ether (RO(cH2CH,0)nH)・Polyoxyethylene alkyl phenyl ether・Polyoxyethylene polystyrylphenyl ni・Polyoxyethylene-polyoxypropylene glycol (However, block polymer,・Polyoxyethylene-polyoxybrobylene alkyl ether (terminals form an alkyl ether) (including random polymers) CH.

Examples include ethylene oxide derivatives of alkylphenol formalin condensates, polyoxyethylene polyhydric alcohol fatty acid partial esters, polyoxyethylene fatty acid esters (for example, RCOO (cHz CHz O) n H), polyoxyethylene alkylamines, and the like.

Specifically, for example, the following are preferable.

Namely, polyoxyethylene lauryl ether, polyoxyethylene cetyl needle, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene higher alcohol ether, polyoxyethylene ocdylphenyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene Oxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tristearate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, polytetraoleate Oxyethylene sorbitol, polyethylene glycol monolaurate, polyethylene glycol monostearate, polyethylene glycol monooleate, polyethylene glycol distearate, polyoxyethylene nonylphenyl ether formaldehyde condensate, oxyethylene oxybrobylene block copolymer, polyethylene glycol, Tetraethylene glycol, etc.

The proportion of the compound having at least one of the structural units [D] and [E] in the photosensitive composition is preferably 0.1 to 20% by weight, more preferably 0.1 to 20% by weight based on the total composition.
．． It is 2 to 10% by weight.

Moreover, the above-mentioned compounds may be used alone or in combination of two or more types, as long as the content is within the above-mentioned range.

In addition to the above-mentioned materials, the photosensitive composition of the present invention may further contain pigments such as dyes and pigments, sensitizers, plasticizers, surfactants, etc., if necessary.

Furthermore, by dissolving each of these components in the following solvent and further applying and drying this on the surface of a suitable support,
A photosensitive layer can be provided to form a photosensitive lithographic printing plate.

Solvents that can be used to dissolve each component of the photosensitive composition of the present invention include cellosolves such as methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve, and ethyl cellosolve acetate, dimethyl formamide, dimethyl sulfoxide, dioxane, acetone, - Examples include cyclohexanone, trichloroethylene, methyl ethyl ketone, etc. These solvents can be used alone or in combination of two or more.

The coating method used for coating the surface of the support with the photosensitive composition of the present invention includes conventionally known methods, such as spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating, and curtain coating. Coating etc. are possible. At this time, the coating amount varies depending on the application, but for example, the solid content is 0.5 to 5. OIJ/12 is preferred.

The support on which the photosensitive layer using the photosensitive composition of the present invention is provided may be a metal plate made of aluminum, zinc, steel, copper, etc., or a plate plated or vapor-deposited with chromium, zinc, copper, nickel, aluminum, iron, etc. Examples include metal plates, paper, plastic films, glass plates, paper coated with resin, paper covered with metal foil such as aluminum, and plastic films treated to make them hydrophilic. Among these, aluminum plates are preferred. As a support for a photosensitive lithographic printing plate using the photosensitive composition of the present invention, it is preferable to use an aluminum plate that has been subjected to surface treatments such as graining, anodizing, and, if necessary, sealing. preferable.

Known methods can be applied to these treatments.

Examples of the graining treatment include a mechanical method and an electrolytic etching method. Examples of mechanical methods include ball polishing, brush polishing, liquid honing, and puff polishing.

The various methods described above can be used alone or in combination depending on the composition of the aluminum material. Preferred is a method using electrolytic etching.

Electrolytic etching is carried out in a bath containing one or a mixture of two or more inorganic acids such as phosphoric acid, sulfuric acid, hydrochloric acid, and nitric acid. After the graining process, desmutting is performed using an alkali or acid aqueous solution as necessary to neutralize the material, followed by washing with water.

The anodic oxidation treatment is performed by electrolyzing using an aluminum plate as an anode using a solution containing one or more of sulfuric acid, chromic acid, oxalic acid, phosphoric acid, malonic acid, etc. as an electrolytic solution. The amount of anodic oxide film formed is 1 to 50 m (1/d
f is appropriate, preferably 10 to 40111 Mdf. The amount of anodized film can be determined by, for example, dipping an aluminum plate in a phosphoric acid chromic acid solution (85% phosphoric acid solution: 35112, prepared by dissolving chromium oxide (■) = 20 o in 12 parts of water) and dissolving the oxide film. However, it can be determined by measuring the weight change before and after dissolving the film on the plate.

Specific 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 a subbing treatment using a water-soluble polymer compound or an aqueous solution of a metal salt such as fluorinated zirconate.

The photosensitive lithographic printing plate to which the photosensitive composition of the present invention is applied is:
It can be developed using a conventional method.

For example, the transparent positive film is exposed to light from a light source such as an ultra-high pressure mercury lamp, metal halide lamp, xenon lamp, or tungsten lamp, and then developed with various alkaline developers. As a result, only the unexposed portion remains on the surface of the support, forming a positive-positive relief image.

Examples of the alkaline developer include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate,
Examples include aqueous solutions of alkali metal salts such as sodium metasilicate, potassium metasilicate, sodium diphosphate, and sodium triphosphate. The concentration of alkali metal salt is 0.
1 to 10% by weight is preferred. Furthermore, an anionic surfactant, an amphoteric surfactant, and an organic solvent such as alcohol can be added to the developer as required.

[Example] (Preparation of aluminum plate) An aluminum plate with a thickness of 0.24 mm (material 1050, tempered H16) was heated in a 5% by weight sodium hydroxide aqueous solution.
After degreasing for 1 minute at 0°C, the temperature: 25°C, current density: 60A/
d1z, treatment time; electrolytic etching treatment was performed under the conditions of 30 seconds. Next, after desmutting in a 5% by weight aqueous sodium hydroxide solution at 60°C for 10 seconds,
Temperature: 20°C, current density: 3A/in 0% by weight sulfuric acid solution
dr, treatment time; anodizing treatment was performed under the conditions of 1 minute.

Furthermore, hot water sealing treatment was performed with hot water at 30°C for 20 seconds.
An aluminum plate as a support for lithographic printing plate material was produced.

Each photosensitive composition coating solution having the composition shown in Table 1 was applied to the aluminum plate prepared above using a spin coater, dried at 90°C for 4 minutes, and positive photosensitive lithographic printing plate sample No. I got ~7.

A step tablet for sensitivity measurement (Eastman
No. 12 manufactured by Kodak Co., gray scale of 21 steps with a density difference of 0.15) was placed in close contact and exposed from a distance of 90 cm using a 2KW metal halide lamp (Idol Fin 2000 manufactured by Iwasaki Electric Co., Ltd.) as a light source. Next, this sample was developed at 27 DEG C. for 20 seconds using a developer prepared by diluting 5DR-1 (manufactured by Konica ■) six times with water. Sensitivity was expressed as the exposure time required to completely clear the 5th and 0th steps of the step tablet.

Next, in order to examine the visible image quality after exposure, the difference in density between the exposed and unexposed areas of the sample before development, which was exposed under the above conditions, was visually observed under a white light and measured using a densitometer (Sakura densitometer PDA-1).
65) through a blue filter. It means that the larger the density difference ΔD is, the better the exposure visible image quality is.

In addition, in order to evaluate printing durability, we used Ultra Plate Cleaner (UPC: A, B, C, manufactured by Chemical Co., Ltd.) as a cleaning liquid during printing to wipe the plate surface every 1,000 sheets. Examined.

We also evaluated the odor generated when aligning the film during the printing process.

Table 2 Umbrella 4: Exposure visible image quality (visual observation) Q: Good Δ: Fairly bad 5: Odor ○: Almost no odor ○ Δ: Very slight odor Δ: Slight odor ×: Significant odor Umbrella 1: Novolac resin/Novolac resin A: Copolycondensation resin of phenol, m-1p-mixed cresol, and formaldehyde [molar ratio of phenol and m,p-mixed cresol is 2.0:8.0, weight average molecular weight MW = 6,000, dispersity MW /Mn = 5, unreacted free phenols (phenol, 1 cresol, p-
Cresol) 4.5% by weight] Novolak Resin B: Same as Novolak Resin A, but unreacted free phenols 3.
5% by weight - Novolac resin C: Same as novolac resin A, but unreacted free phenols 3.
0% by weight - Novolak resin D: Same as novolak resin A, but unreacted free phenols 2.
0% by weight - Novolac resin E - Copolycondensation resin of cresol, p-cresol and formaldehyde (molar ratio of -1-cresol and p-cresol 6:4, MW = 5,500, MW/Mn =
4.5, 3.5% by weight of unreacted free phenols) Novolak resin (a): 10% by weight of unreacted free phenols 2; Quinonediazide compound of the present invention QD-6 QD-'5 Compound No. 3 in which Q has the following structure: Free radical-forming compounds As is clear from Table 2, photosensitive planographic printing plate sample No. prepared using the photosensitive composition of the present invention.

Samples Nos. 1 to 5 were all superior in sensitivity and exposure visible image quality, and also had excellent printing durability, compared to samples Nos. 016 and 7 prepared from photosensitive compositions other than those of the present invention. Furthermore, there was almost no odor during production, and the environment was excellent.

[Effects of the Invention] As explained in detail above, the photosensitive composition of the present invention provides a photosensitive lithographic printing plate that has high sensitivity and excellent exposure visible imageability and provides excellent printing durability. can do. Furthermore, the odor during production is also improved.

Claims (1)

[Scope of Claims] (a) 1,2-naphthoquinone-2-diazide-4-sulfonic acid ester compound, (b) novolac resin containing less than 5% by weight of phenols, and (c) irradiation with actinic rays. A photosensitive material characterized by containing a halomethyloxadiazole compound and/or a halomethyl S-triazine compound that generates halogen free radicals, and (d) a color change agent that changes the color tone by interacting with the halogen free radicals. sexual composition.