JPH05181269A - Photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To obtain a photosensitive planographic printing plate having high liposensitive and sensitivity by incorporating a specified polymer compd. and a diazo resin into a photosensitive layer. CONSTITUTION:A polymer compd. and a diazo resin expressed by formulae (I)-(IV) (wherein R<1>, R<2>, R<3>, R<3+a> are hydrogen atoms, alkyl groups, or aryl groups, and A or B represents an end group) are incorporated into a photosensitive layer on a supporting body. This polymer compd. acts as a sensitization agent. The amt. of these compds. in the photosensitive layer is 0.5-30wt.%. As for the diazo resin to be used as a photosensitive material, it is preferable to use condensation copolymer diazo resins consisting of aromatic diazonium compd. and aromatic compd. having carboxyl groups or hydroxyl groups as the structural units. By this constitution, a photosensitive planographic printing plate having good ink depositing property is obtd. without decreasing the sensitivity.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a photosensitive lithographic printing plate.

[0002]

BACKGROUND OF THE INVENTION Various photosensitive lithographic printing plates (hereinafter sometimes referred to as PS plates) have been proposed.

For example, conventionally, a photosensitive lithographic printing plate having a photosensitive layer containing a diazo resin as a photosensitive compound has been proposed.

When the photosensitive printing plate is, for example, a negative type, it is usually irradiated with a light beam through a negative image or the like, and the part irradiated with light is polymerized or crosslinked to make this part insoluble in a developing solution. , And then develop to elute the non-irradiated areas in the developer, and each area is defined as an image area that repels water and receives oil-based ink, and a non-image area that receives water and repels oil-based ink. It is generally used in the form.

However, a conventional photosensitive lithographic printing plate using a diazo resin, for example, a conventional negative PS plate generally has a low surface oil sensitivity, and has insufficient ink receptivity during printing, or printing. There was a problem that a large amount of spoiled paper (called scrap paper) was generated.

[0006]

As described above, a conventional negative photosensitive lithographic printing plate having a photosensitive layer composed of a diazo resin and a binder is, for example, an oil-based ink used for sensitizing the image area, that is, lithographic printing. The ability to accept is low.
For this reason, when printing is performed using a conventional printing plate, there is a problem that a large number of prints with poor ink-feeding, that is, a low image density, are produced from the start of printing until a print showing normal ink inking is obtained. is there. It is not preferable in terms of cost and working time that there are many printed matters (waste paper) showing defective inking, and therefore it is desired to solve such a problem.

In order to solve this problem, various techniques have been proposed, for example, techniques using various sensitizers. However, when various conventional oil sensitizers are added to form a photosensitive layer, the added oil sensitizers are dissolved during development and the effect required during printing cannot be enhanced, and the effect is insufficient. However, there is a problem that performance such as sensitivity is deteriorated.

An object of the present invention is to solve the above problems and
An object of the present invention is to provide a photosensitive lithographic printing plate having sufficient oil sensitivity (ink receptivity) and good sensitivity.

[0009]

In order to solve the above-mentioned problems, the photosensitive lithographic printing plate of the present invention has one of the following general formulas (1) to (4) on at least one surface of a support. The photosensitive layer contains a diazo resin and at least one polymer compound arbitrarily selected from the group of polymer compounds represented by

[Chemical 2]

In the general formulas (1) to (4), R ¹ , R ² and R
³ , ..., R3 + a are hydrogen atoms, alkyl groups (including those having a substituent), or aryl groups (including those having a substituent). However, in each formula, not all hydrogen atoms are taken. A and B represent terminal groups.
l, m, n, ..., N + a are numbers determined by the degree of polymerization in each formula. In the general formula (4), a is a number of 1 or more and 17 or less.

The present invention will be further described below. In the photosensitive layer of the photosensitive lithographic printing plate according to the present invention, the general formula (1)
Any at least one polymer compound represented by any one of (4) (hereinafter may be appropriately referred to as “polymer compound of the present invention”) is contained. explain.

In the general formulas (1) to (4), R ¹ , R
² , R ³ , ..., R ³ + a are hydrogen atoms, alkyl groups (including those having a substituent), or aryl groups (including those having a substituent), provided that in each formula, Not all of them take hydrogen atoms, but in this case, the alkyl group preferably has 1 to 25 carbon atoms (the number of carbon atoms in the alkyl portion of the main chain when having a substituent), preferably 1 to 10 carbon atoms. Those are more preferable. In the case of a substituted alkyl group, a substituent having a halogen atom, a hydroxy group, an alkoxy group, an amino group, a carboxyl group, an aryl group or the like is preferable as the substituent bonded to the alkyl group. When it is an aryl group, it preferably has 6 to 20 carbon atoms (the carbon number of the aryl group portion when it has a substituent). R
When there are two or more of ¹ , R ² ... R ¹ , R ² ·
Any of the ... May be hydrogen. In addition, R ¹ , R ²
Both may be a (substituted) alkyl group or a (substituted) aryl group, and the combination thereof is arbitrary. In the general formula (2), the ratio of 1: m is arbitrary, but is 50: 5.
0 to 96: 4 is preferable. In the general formula (3), l:
The ratio of m: n is arbitrary, but (l + m): n = 50: 5
0 to 96: 4 is preferable. In the general formula (4),
The ratio of l: m: n: ...: n + a is arbitrary.

When there are hydrogen atoms in R ¹ , R ^2, ..., The total amount of hydrogen atoms is preferably 50 mol% or less. The weight average molecular weight of the polymer compound of the present invention is preferably 1,000 to 100,000.

Various means can be employed for synthesizing the polymer compound of the present invention. For example, when synthesizing the polymer compound of the present invention, fumaric acid diester, fumaric acid monoester, maleic acid diester, maleic acid monoester. A homopolymerization or copolymerization reaction of a monomer selected from the ester can be used. As the polymerization reaction, radical polymerization, cationic polymerization, anionic polymerization or the like can be used, but radical polymerization is suitable. Specific examples of the monomer to be used include dimethyl fumarate, diethyl fumarate, di-n-propyl fumarate, diisopropyl fumarate, di-n-butyl fumarate, di-t-butyl fumarate, di-isobutyl fumarate, and fumarate. Acid dipropyl, dihexyl fumarate, diheptyl fumarate, dioctyl fumarate, dinonyl fumarate, didecyl fumarate, monomethyl fumarate,
Monoethyl fumarate, monoisopropyl fumarate, mono-n-propyl fumarate, mono-n-butyl fumarate,
Mono-isobutyl fumarate, mono-t-butyl fumarate, monopropyl fumarate, monohexyl fumarate, monoheptyl fumarate, monooctyl fumarate, monononyl fumarate, monodecyl fumarate, diphenyl fumarate, ditolyl fumarate, fumarate Examples include maleic acid diesters and maleic acid monoesters similar to fumaric acid esters such as dibenzyl, methylphenyl fumarate, and ethylbenzyl fumarate.

Next, synthetic examples of the polymer compound of the present invention will be shown. (Synthesis Method of Polymer Compound A) Di-n-butyl fumarate 2
28 g was dissolved in a mixed solvent of 100 ml of methanol and 100 ml of acetone, and azobisisobutyronitrile 3.2 was added.
Add 8 g. After distilling under a nitrogen stream for 6 hours, the reaction solution was poured into 3 liters of water, and the obtained white precipitate was collected by filtration and dried,
Polymer compound A was obtained. The weight average molecular weight of the polymer compound A measured by GPC was 12,000.

(Synthesis Method of Polymer Compound B) In the synthesis method of Polymer Compound A, 228 g of di-n-butyl fumarate was used.
Instead of, 86 g of diethyl fumarate and 96 g of monophenyl fumarate were synthesized in the same manner to obtain polymer compound B.
Got The weight average molecular weight was 16,000.

In the photosensitive lithographic printing plate of the present invention, the polymer compound of the present invention functions as an oil sensitizer. The preferable content of the compound of the present invention in the photosensitive layer is 0.5.
To 30% by weight, more preferably 1 to 20% by weight
Is.

Next, the diazo resin contained in the photosensitive layer of the photosensitive lithographic printing plate of the present invention will be described.

The above diazo resin is used as a photoconductor. Any diazo resin can be used in the present invention.

In the present invention, as the diazo resin, a co-condensed diazo resin containing an aromatic compound having at least one of at least one of a carboxyl group and a hydroxyl group and an aromatic diazonium compound as constitutional units is preferably used. You can

Such an aromatic compound having a carboxyl group and / or a hydroxy group has an aromatic ring substituted with at least one carboxyl group and / or an aromatic ring substituted with at least one hydroxyl group in the molecule. In this case, the carboxyl group and the hydroxyl group may be substituted with the same aromatic ring or may be substituted with another aromatic ring. This carboxyl group or hydroxyl group may be directly bonded to the aromatic ring, or may be bonded via a bonding group. Preferred examples of the above-mentioned aromatic group include an aryl group such as a phenyl group and a naphthyl group.

In the co-condensed diazo resin usable in the present invention, the number of carboxyl groups bonded to one aromatic ring is preferably 1 or 2, and the number of hydroxyl groups bonded to one aromatic ring is preferably 1. 1 to 3 is preferable. When the carboxyl group or the hydroxyl group is bonded to the aromatic ring via the bonding group, examples of the bonding group include an alkylene group having 1 to 4 carbon atoms.

Specific examples of the aromatic compound containing a carboxyl group and / or a hydroxyl group as the constitutional unit of the co-condensed diazo resin include benzoic acid, o-chlorobenzoic acid, m-chlorobenzoic acid and p-chloro. Benzoic acid, phthalic acid, terephthalic acid, diphenylacetic acid, phenoxyacetic acid, p-methoxyphenylacetic acid, p-methoxybenzoic acid, 2,4-dimethoxybenzoic acid, 2,4-dimethylbenzoic acid, p-phenoxybenzoic acid, 4 -Anilinobenzoic acid, 4- (m-methoxyanilino) benzoic acid, 4- (p
-Methylbenzoyl) benzoic acid, 4- (p-methylanilino) benzoic acid, 4-phenylsulfonylbenzoic acid, phenol, (o, m, p) -cresol, xylenol, resorcin, 2-methylresorcin, (o, m,
p) -methoxyphenol, m-ethoxyphenol,
Catechol, phloroglysin, p-hydroxyethylphenol, naphthol, pyrogallol, hydroquinone,
p-hydroxybenzyl alcohol, 4-chlororesorcin, biphenyl-4,4'-diol, 1,2,4-
Benzenetriol, bisphenol A, 2,4-dihydroxybenzophenone, 2,3,4-trihydroxybenzophenone, p-hydroxyacetophenone, 4,
4-dihydroxydiphenyl ether, 4,4′-dihydroxydiphenylamine, 4,4′-dihydroxydiphenyl sulfide, cumylphenol, (o, m,
p) -chlorophenol, (o, m, p) -bromophenol, salicylic acid, 4-methylsalicylic acid, 6-methylsalicylic acid, 4-ethylsalicylic acid, 6-propylsalicylic acid, 6-laurylsalicylic acid, 6-stearylsalicylic acid, 4 , 6-dimethylsalicylic acid, p-hydroxybenzoic acid, 2-methyl-4-hydroxybenzoic acid, 6
-Methyl-4-hydroxybenzoic acid, 2,6-dimethyl-4-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,4-dihydroxy-6-methylbenzoic acid,
2,6-dihydroxybenzoic acid, 2,6-dihydroxy-4-benzoic acid, 4-chloro-2,6-dihydroxybenzoic acid, 4-methoxy-2,6-dioxybenzoic acid, gallic acid, phloroglucin carvone Acid, 2,4,5-trihydroxybenzoic acid, m-galloyl gallic acid, tannic acid, m-benzoyl gallic acid, m- (p-toluyl) gallic acid, protocatechuyl gallic acid, 4,6-dihydroxy Phthalic acid, (2,4-dihydroxyphenyl)
Acetic acid, (2,6-dihydroxyphenyl) acetic acid, (3,
4,5-trihydroxyphenyl) acetic acid, p-hydroxymethylbenzoic acid, p-hydroxyethylbenzoic acid, 4
-(P-hydroxyphenyl) methylbenzoic acid, 4-
(O-Hydroxybenzoyl) benzoic acid, 4- (2,4
-Dihydroxybenzoyl) benzoic acid, 4- (p-hydroxyphenoxy) benzoic acid, 4- (p-hydroxyanilino) benzoic acid, bis (3-carboxy-4-hydroxyphenyl) amine, 4- (p-hydroxyphenyl) Examples thereof include sulfonyl) benzoic acid and 4- (p-hydroxyphenylthio) benzoic acid. Of these, particularly preferable are salicylic acid, p-hydroxybenzoic acid, p-methoxybenzoic acid, and metachlorobenzoic acid.

The aromatic diazonium compound used as the constitutional unit of the co-condensed diazo resin is, for example, Japanese Patent Publication No. 49-48.
Although diazonium salts such as those listed in No. 001 can be used, diphenylamine-4-diazonium salts are particularly preferable. The diphenylamine-4-diazonium salts are derived from 4-amino-diphenylamines, and such 4-amino-diphenylamines include 4-amino-diphenylamine, 4-amino-3-methoxy-diphenylamine, 4-amino-diphenylamine and 4-amino-3-methoxy-diphenylamine. Amino-2-
Methoxy-diphenylamine, 4'-amino-2-methoxy-diphenylamine, 4'-amino-4-methoxydiphenylamine, 4-amino-3-methyldiphenylamine, 4-amino-3-ethoxy-diphenylamine, 4-amino-3- Examples thereof include β-hydroxy-ethoxydiphenylamine, 4-amino-diphenylamine-2-sulfonic acid, 4-amino-diphenylamine-2-carboxylic acid and 4-amino-diphenylamine-2′-carboxylic acid. Particularly preferred are 3-methoxy-4-amino-diphenylamine and 4-amino-diphenylamine.

As the copolymerized diazo resin which can be used in the present invention, those represented by the following general formula (5) are preferable.

[Chemical 3]

In the general formula (5), A is a group derived from an aromatic compound having at least one of a carboxyl group and a hydroxyl group, and examples of such an aromatic compound include those exemplified above. it can.

In the formula, R ¹¹ , R ¹² and R ¹³ represent a hydrogen atom, an alkyl group or a phenyl group, R represents a hydrogen atom, an alkyl group or a phenyl group, and X represents a counter anion. n preferably represents a number of 1 to 200.

When a co-condensed diazo resin is used in the present invention, it is more preferably used in combination with a condensed diazo resin obtained by condensing an aromatic diazonium compound.

In this case, the co-condensed diazo resin is 5% by weight or more in the diazo resin, and the condensed diazo resin is
It is preferably used in an amount of 95% by weight or less in the diazo resin. Further, in this case, the weight ratio of co-condensed diazo resin: condensed diazo resin is particularly preferably from 30 to 70: from the viewpoint of excellent sensitivity and developability.
70 to 30.

The above-mentioned co-condensed diazo resin and the condensed diazo resin used in combination therewith or independently as the diazo resin are known in the art, for example, Photographic Science and Engineering (Phot).
o. Sci. Eng. ) Volume 17, page 33 (197)
3), U.S. Pat. Nos. 2,063,631 and 2,67
According to the method described in each specification of 9,498, aromatic compounds and aldehydes having a diazonium salt, carboxy and hydroxyl groups in sulfuric acid, phosphoric acid or hydrochloric acid,
For example, it can be obtained by polycondensation with paraformaldehyde, acetaldehyde, benzaldehyde or ketones such as acetone and acetophenone.

The aromatic compounds, aromatic diazo compounds and aldehydes or ketones having a carboxyl group and / or a hydroxyl group in these molecules can be freely combined with each other, and two or more kinds of them can be mixed and co-condensed. It is also possible to do so.

The charged molar ratio of the aromatic compound having at least one of a carboxyl group and a hydroxyl group to the aromatic diazonium compound is preferably 1: 0.1.
0.1: 1, more preferably 1: 0.5 to 0.2: 1,
More preferably, it is 1: 1 to 0.2: 1. Further, in this case, the total of the aromatic compound and the aromatic diazonium compound having at least one of a carboxyl group and a hydroxyl group and the aldehyde or the ketone are usually preferably in a molar ratio of 1: 0.6 to 1.2, and more preferably Is 1:
A co-condensed diazo resin is obtained by charging at 0.7 to 1.5 and reacting at low temperature for a short time, for example, for about 3 hours.

The counter anion of the diazo resin includes an anion which forms a salt with the diazo resin in a stable manner and makes the resin soluble in an organic solvent. Examples of such anions include organic carboxylic acids such as decanoic acid and benzoic acid and benzoic acid, organic phosphoric acids such as phenylphosphoric acid and sulfonic acid, and typical examples include methanesulfonic acid, Chloroethanesulfonic acid, dodecanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, mesitylenesulfonic acid, and anthraquinonesulfonic acid, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid,
Aliphatic and aromatic sulfonic acids such as hydroxysulfonic acid, 4-acetylbenzenesulfonic acid, dimethyl-5-sulfoisophthalate, 2,2 ', 4,4'-tetrahydroxybenzophenone, 1,2,3-trihydroxy benzophenone, 2,2 ', 4-hydroxyl group-containing aromatic compound of trihydroxy benzophenone, hexafluorophosphate, halide Lewis acids such as tetrafluoroboric acid, the like ClO _4, perhalogenic acid IO ₄ such like You can However, it is not limited to this. Among these, particularly preferable are hexafluorophosphoric acid and 2-
Hydroxy-4-methoxybenzophenone-5-sulfonic acid.

The molecular weight of the above co-condensed diazo resin can be obtained as an arbitrary value by variously changing the molar ratio of each monomer and the condensation conditions. In the present invention, it is generally preferred that the molecular weight is about 400 to 10,000.
Those of about 800 to 5,000 are suitable, and those of about 800 to 5,000 are more suitable.

In the present invention, in addition to the above-mentioned co-condensed diazo resin, those which can be preferably used as the diazo resin include, for example, the above-mentioned Photographic Science and Engineering (Photo.Sci.
Eng. ) Volume 17, page 33 (1973) and U.S. Pat. Nos. 2,063,631 and 2,679,498,
No. 3,050,502, JP-A-59-783
No. 40, etc., the production method is described, and a diazo resin obtained by condensing an active carbonyl compound such as formaldehyde, acetaldehyde or benzaldehyde in an acidic medium such as sulfuric acid, phosphoric acid, hydrochloric acid, etc. Examples of the diazo compound and diphenyl resin whose production method is described in JP-A-49-4001 can be cited.

Among the above, the diazo resin which can be preferably used in the present invention is represented by the following general formula (6), and 20 mol% of the resin in which n in each formula is 5 or more is used.
Above, more preferably, it contains 20 to 60 mol%. In the formula, R ^{11 to} R ¹³ , R, X, and n have the same meanings as in the general formula (5). In the general formula (6), examples of the alkyl group and the alkoxy group of R ¹¹ , R ¹² and R ¹³ include an alkyl group having 1 to 5 carbon atoms and an alkoxy group having 1 to 5 carbon atoms. Examples of the alkyl group include alkyl groups having 1 to 5 carbon atoms.

[Chemical 4]

The photosensitive diazo resin can be prepared by a known method,
For example, it can be manufactured according to the methods described in the above-mentioned US Pat.

At this time, in the polycondensation of the diazonium salt and the aldehyde, both are usually in a molar ratio of 1:
0.6-1: 2, preferably 1: 0.7-1: 1.5
Then, the high-sensitivity diazo resin is obtained by reacting at low temperature for a short time, for example, at 10 ° C. or less for about 3 hours.

As the counter anion of the diazo resin represented by the general formula (6), the same counter anions as those mentioned for the co-condensed diazo resin can be mentioned.

Next, the photosensitive lithographic printing plate of the present invention contains at least one of the above-mentioned polymer compounds represented by the general formulas (1) to (4), which functions as an oil sensitizer, and the above-mentioned. It is preferable to include a polymer compound as a binder in the photosensitive layer together with the diazo resin.

In the present specification, in order to specify the molecular weights of various polymer compounds including the polymer compound as a binder described below, the value of the molecular weight measured by GPC according to polystyrene standard can be used. That is,
The weight average molecular weight can be measured by GPC (gel permeation chromatography method), and the number average molecular weight Mn and the weight average molecular weight MW can be calculated by Morio Tsuge, Tatsuya Miyabayashi, and Masayuki Tanaka, "Chemical Society of Japan", p. 800. ~
According to the method described on page 805 (1972), it can be carried out by a method of leveling the peaks in the oligomer region (connecting the peak and valley center lines).

The polymer compound as a binder that can be used in the present invention may be of any type, and the following compounds can be used, for example. That is, as the polymer compound that can be used, polyamide, polyether, polyester, polycarbonate, polystyrene, polyurethane, polyvinyl chloride and copolymers thereof, polyvinyl butyral resin, polyvinyl formal resin, shellac, epoxy resin, phenol resin, acrylic resin, etc. Is mentioned.

Preferred are copolymers of the monomers shown in the following (1) to (12).

(1) A monomer having an aromatic hydroxyl group, for example, N- (4-hydroxyphenyl) acrylamide or N- (4-hydroxyphenyl) methacrylamide, o-, m-, p-hydroxystyrene, o-, m.
-, P-hydroxyphenyl-acrylate or -methacrylate.

(2) Monomers having an aliphatic hydroxyl group, such as 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate.

(3) α, β-of acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, itaconic anhydride, etc.
Unsaturated carboxylic acid.

(4) Methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate,
(Substituted) alkyl acrylates such as 2-chloroethyl acrylate, 2-hydroxyethyl acrylate, glycidyl acrylate, N-dimethylaminoethyl acrylate.

(5) Methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, cyclohexyl methacrylate, 2-hydroxyethyl methacrylate, 4-
(Substituted) alkyl methacrylates such as hydroxybutyl methacrylate, glycidyl methacrylate and N-dimethylaminoethyl methacrylate.

(6) Acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N-ethylacrylamide, N-hexylacrylamide, N-cyclohexylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, N- Acrylamide or methacrylamide such as nitrophenylamide and N-ethyl-N-phenylacrylamide.

(7) Ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, butyl vinyl ether,
Vinyl ethers such as octyl vinyl ether and phenyl vinyl ether.

(8) Vinyl acetates such as vinyl acetate, vinyl chloroacetate, vinyl butyrate and vinyl benzoate.

(9) Styrenes such as styrene, α-methylstyrene, methylstyrene and chloromethylstyrene.

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

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

(12) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, acrylonitrile, methacrylonitr and the like.

Further, a monomer copolymerizable with the above-mentioned monomer may be copolymerized. In addition, a copolymer pair obtained by copolymerizing the above-mentioned monomers is also modified, for example, with glycidyl methacrylate, glycidyl acrylate, etc., but is not limited thereto.

More specifically, a hydroxyl group-containing copolymer containing the monomers listed in (1) and (2) above is preferable, and an aromatic hydroxyl group-containing copolymer is more preferable.

If necessary, polyvinyl butyral resin, polyurethane resin, polyamide resin, epoxy resin, novolac resin, natural resin or the like may be added to the above copolymer.

In the present invention, the following copolymers are particularly preferable as the polymer compound as the binder.

That is, the structural unit (a) having a carboxyl group in the molecular structure is 2 mol% or more, preferably 3 to 2
0 mol%, (b) 1 unit of a structural unit having an alcoholic hydroxyl group and / or a structural unit having a phenolic hydroxyl group
˜50 mol%, (c) the following general formula (7)

[Chemical 5]

(Wherein R ²¹ represents a hydrogen atom or an alkyl group), a structural unit represented by 5 to 40 mol%,
(D) The following general formula (8)

[Chemical 6]

(Wherein R ²² represents a hydrogen atom, a methyl group or an ethyl group, and R ²³ represents an alkyl group having 1 to 12 carbon atoms or an alkyl-substituted aryl group). Polymer compounds containing 25 to 60 mol% are preferred.

Specific examples of the monomer forming the structural unit having an alcoholic hydroxyl group of the above (b) include the following general formula (9) as described in JP-B-52-7364.
(Meth) acrylic acid esters and acrylamides such as the compounds shown in 1.

[Chemical 7]

In the formula, R ²⁴ is a hydrogen atom or a methyl group, and R ²⁴ is
²⁵ represents a hydrogen atom, a methyl group, an ethyl group or a chloromethyl group, and n represents an integer of 1 to 10.

Examples of (meth) acrylic acid esters include 2-hydroxyethyl (meth) acrylate and 2-hydroxyethyl (meth) acrylate.
Hydroxypropyl (meth) acrylate, 2-hydroxypentyl (meth) acrylate and the like, and examples of acrylamides include N-methylol (meth) acrylamide and N-hydroxyethyl (meth) acrylamide. 2-hydroxyethyl (meth) acrylate is preferable.

Examples of the monomer (b) for forming the structural unit having a phenolic hydroxyl group include N- (4-hydroxyphenyl)-(meth) acrylamide and N- (2-hydroxyphenyl)-( Monomers of (meth) acrylamides such as (meth) acrylamide, N- (4-hydroxynaphthyl)-(meth) acrylamide; o-, m- or p-hydroxyphenyl (meth) acrylate monomers; o-, m- or p -Hydroxystyrene monomer and the like. Preferably,
o-, m- or p-hydroxyphenyl (meth) acrylate monomer, N- (4-hydroxyphenyl)-
It is a (meth) acrylamide monomer, more preferably an N- (4-hydroxyphenyl)-(meth) acrylamide monomer.

The structural unit having an alcoholic hydroxyl group and / or the structural unit having a phenolic hydroxyl group is
In the polymer compound, 1 to 50 mol%, preferably 5 to 3
It is selected from the range of 0 mol%.

The monomer having a cyano group in the side chain forming the structural unit represented by the general formula (7) includes acrylonitrile, methacrylonitrile, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, o-, m-, p-cyanostyrene and the like can be mentioned. Preferred are acrylonitrile and methacrylonitrile. The ratio of the structural unit having a cyano group in the side chain contained in the molecule of the polymer compound is preferably 5 to 40 mol%, more preferably 15 to 35 mol%.

Examples of the monomer having a carboxy ester group in the side chain which forms the structural unit represented by the general formula (8) include ethyl acrylate, ethyl methacrylate, propyl acrylate, butyl acrylate, amyl acrylate and amyl methacrylate. , Hexyl acrylate, octyl acrylate, 2-chloroethyl acrylate, 2-hydroxyethyl acrylate, glycidyl acrylate and the like. The unit formed from the monomer is preferably 25 to 25 in the polymer compound.
60 mol%, more preferably 35 to 60 mol% is selected.

The above structural units are not limited to the units formed from the monomers given as specific examples.

The polymer compound contained in the photosensitive layer of the photosensitive lithographic printing plate of the present invention is preferably 40 to 99% by weight, more preferably usually, in the solid content of the photosensitive composition constituting the photosensitive layer. Is contained in an amount of 50 to 95% by weight. Further, the photosensitive diazo resin contained in the photosensitive material according to the present invention,
Similarly, the content is usually preferably 1 to 60% by weight, more preferably 3 to 30% by weight.

The photosensitive layer of the photosensitive lithographic printing plate of the present invention can contain an acid and / or an acid anhydride.

In this case, the acid contained in the photosensitive layer can be arbitrarily selected from organic acids and inorganic acids. As the organic acid, an acid having at least one carboxyl group of monocarboxylic acid or polycarboxylic acid is preferable. Malic acid, tartaric acid, and polyacrylic acid (commercially available under the trade name Jurimer) can be preferably used. Phosphoric acid or the like can be used as the inorganic acid.

In the case of containing an acid anhydride, the kind of the acid anhydride is optional, and those derived from an aliphatic / aromatic monocarboxylic acid such as acetic anhydride, propionic anhydride, benzoic anhydride, and amber Examples thereof include acids, maleic anhydride, glutaric anhydride, phthalic anhydride, and the like derived from aliphatic / aromatic dicarboxylic acids.

The light-sensitive material composition for forming the light-sensitive layer of the light-sensitive lithographic printing plate of the present invention may contain a dye, particularly a dye that changes from colored to colorless or discolors upon treatment. Preferably, a dye that changes from colored to colorless is included.

The following are examples of dyes that can be preferably used in the practice of the present invention.

That is, for example, Victoria Pure Blue B
OH (Hodogaya Chemical Co., Ltd.), Oil Blue # 603 (Orient Chemical Co., Ltd.), Patent Pure Blue (Sumitomo Mikuni Chemical Co., Ltd.), Crystal Violet, Brilliant Green, Ethyl Violet, Methyl Violet,
Triphenyl typified by methyl green, erythrosine B, basic fuchsin, malachite green, oil red, m-cresol purple, rhodamine B, auramine, 4-p-dimethylaminophenyliminonaphthoquine, cyano-p-diethylaminophenylacetanilide and the like. Methane-based, diphenylmethane-based, oxazine-based, xanthene-based, iminonaphthoquinone-based, azomethine-based or anthraquinone-based dyes can be mentioned as examples of dyes that change color from colorless to a different color.

Particularly preferred are triphenylmethane-based and diphenylmethane-based dyes, more preferred are triphenylmethane-based dyes, and Victoria Pure Blue BOH is particularly preferred.

The above color-changing agent is usually contained in the photosensitive layer in an amount of about 0.5-.
The content is preferably about 10% by weight, more preferably about 1 to 5% by weight.

Various additives can be further added to the photosensitive composition forming the photosensitive layer of the photosensitive lithographic printing plate of the present invention.

Examples of the additives include alkyl ethers (eg, ethyl cellulose and methyl cellulose) for improving coating properties, fluorosurfactants, and nonionic surfactants [eg, Bourronic L-64 (manufactured by Asahi Denka Co., Ltd. )], A plasticizer for imparting flexibility and abrasion resistance to the coating film (for example, butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate,
Tricresyl phosphate, tributyl phosphate, trioctyl phosphate, tetrahydrofurfuryl oleate, oligomers and polymers of acrylic acid or methacrylic acid), stabilizers [eg phosphoric acid, phosphorous acid, organic acids (citric acid,
Oxalic acid, benzenesulfonic acid, naphthalenesulfonic acid, 4-methoxy-2-hydroxybenzophenone-5
-Sulfonic acid, tartaric acid, etc.)] and the like. The amount of these additives added varies depending on the intended use and purpose, but is generally preferably 0.01 to 3 relative to the total solid content.
It is 0% by weight.

To install such a photosensitive layer on a support, the above-mentioned diazo resin and, if necessary, various amounts of various additives are added in a suitable solvent (methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, acetone). , Methyl ethyl ketone, methanol, dimethylformamide,
The coating solution of the photosensitive composition may be prepared by dissolving it in dimethyl sulfoxide, water or a mixture thereof, etc., and the solution may be coated on a support and dried. The concentration of the photosensitive composition at the time of coating is preferably in the range of 1 to 50% by weight. In this case, the coating amount of the photosensitive composition is preferably about 0.2 to 10 g / m ² .

In the photosensitive lithographic printing plate of the present invention, the support for coating the photosensitive composition to form a photosensitive layer is
Various ones can be used. When used in a photosensitive lithographic printing plate, an aluminum plate is particularly preferable. However, when the aluminum plate is used without treatment, there are problems that the adhesiveness of the photosensitive composition is poor and the photosensitive composition is decomposed. In order to eliminate this problem, various proposals have hitherto been made.

For example, a method in which the surface of an aluminum plate is grained and then treated with silicate (US Pat. No. 2,71,71)
4,066), a method of treating with an organic acid salt (US Pat. No. 2,714,066), a method of treating with phosphonic acid and derivatives thereof (US Pat. No. 3,220,832).
Of treating with potassium hexafluorozirconate
(U.S. Pat. No. 2,946,683), a method of anodizing, a method of treating with an aqueous solution of alkaline metal silicate after anodizing (US Pat. No. 3,181,461), and the like.

In a preferred embodiment of the invention,
Aluminum plate (including alumina laminate, the same applies below)
After degreasing the surface, brush polishing method, ball polishing method,
Graining is performed by a chemical polishing method, an electrolytic etching method, or the like, and preferably, an electrolytic etching method that can obtain a deep and uniform grain is performed. The anodizing treatment is carried out by using, for example, an inorganic salt such as phosphoric acid, chromic acid, boric acid, sulfuric acid or the like, or an organic acid such as oxalic acid alone, or an aqueous solution in which two or more kinds of these acids are mixed, preferably an aqueous sulfuric acid solution It is performed by passing an electric current through an aluminum plate as an anode. Anodic oxide coating weight is preferably 5~600mg / dm ^2, more preferably from 5 to 30 mg / dm ^2.

When carrying out the pore-sealing treatment in the practice of the present invention, the treatment is preferably carried out by immersing in a sodium silicate aqueous solution having a concentration of 0.1 to 3% at a temperature of 80 to 95 ° C. for 10 seconds to 2 minutes. .. More preferably, it is then immersed in water at 40 to 95 ° C. for 10 seconds to 2 minutes for treatment.

The developing solution for developing the photosensitive lithographic printing plate of the present invention is optional as long as it can develop the developing solution.

Preferably, a developer containing a specific organic solvent, an alkaline agent and water as necessary components can be used. Here, the specific organic solvent means a solvent capable of dissolving or swelling the non-exposed area (non-image area) of the layer comprising the photosensitive composition of the present invention, when contained in the developer, and An organic solvent having a solubility in water of 10% by weight or less at room temperature (20 ° C) is preferable.

As such an organic solvent, any organic solvent may be used as long as it has the above-mentioned characteristics, and the organic solvent is not limited to the following. For example, ethyl acetate, Propyl acetate, butyl acetate,
Carboxylic acid esters such as amyl acetate, benzyl acetate, ethylene glycol monobutyl acetate, butyl lactate, butyl levulinate; ketones such as ethyl butyl ketone, methyl isobutyl ketone, cyclohexanone;
Alcohols such as ethylene glycol monobutyl ether, ethylene glycol benzyl ether, ethylene glycol monophenyl ether, benzyl alcohol, methylphenyl carbinol, n-amyl alcohol, methyl amyl alcohol; alkyl-substituted aromatic hydrocarbons such as xylene; methylene There are halogenated hydrocarbons such as dichloride, ethylene dichloride and monochlorobenzene. One or more of these organic solvents may be used. Among these organic solvents, ethylene glycol monophenyl ether and benzyl alcohol are particularly effective. Further, the content of these organic solvents in the developer is preferably about 1 to 20% by weight, and particularly preferable results are obtained when the content is 2 to 10% by weight.

On the other hand, preferred alkaline agents contained in the developing solution include (A) sodium silicate, potassium silicate, potassium hydroxide, sodium hydroxide, lithium hydroxide, and sodium di- or triphosphate. , Inorganic alkali agents such as sodium carbonate and ammonium, (B) mono,
Di or trimethylamine, mono, di or triethylamine, mono or diisopropylamine, n-butylamine, mono, di or triethanolamine, mono,
Examples thereof include organic amine compounds such as di- or triisopropanolamine, ethyleneimine and ethylenediamine.

The content of these alkaline agents in the developing solution is usually preferably 0.05 to 4% by weight, more preferably 0.5 to 2% by weight.

Further, in order to further improve the storage stability, printing durability and the like, it is preferable to include a water-active sulfite in the developer. As such a water-soluble sulfite, an alkali or alkaline earth metal salt of sulfite is preferable, and examples thereof include sodium sulfite, potassium sulfite, lithium sulfite and magnesium sulfite. The content of these sulfites in the developer composition is usually preferably 0.05 to 4% by weight, more preferably 0.1 to 1% by weight.

When such a developing solution is brought into contact with the photosensitive composition after development exposure or rubbed with the developing solution, the exposed portion of the photosensitive layer is adversely affected after 10 to 60 seconds at room temperature to 40 ° C. The development is carried out by completely removing the non-exposed portion without affecting.

[0094]

EXAMPLES Examples of the present invention will be described below. As a matter of course, the present invention is not limited to the following examples.

In each of the following examples, the following polymer compounds (1) and (2), which are alkali-soluble and swellable polymer compounds, were used as the binder resin. The following diazo resins 1 and 2 were used as the diazo resin.

Synthesis of polymer compound (1) N- (4-hydroxyphenyl) methacrylamide 1
7.7 g, methacrylic acid 8.6 g, acrylonitrile 1
0.6 g, 60.0 g of ethyl acrylate, and 1.64 g of azobisisobutyronitrile were dissolved in 130 ml of an acetone-methanol 1: 1 mixed solution, the atmosphere was replaced with nitrogen, and the mixture was heated at 60 ° C. for 6 hours.

After the reaction was completed, the reaction solution was poured into 5 liters of water with stirring, and the white precipitate formed was collected by filtration and dried to obtain 87 g of polymer compound (1).

The molecular weight of this polymer compound (1) was measured by gel permeation chromatography (hereinafter abbreviated as GPC. Polystyrene standard), and the weight average molecular weight was 82,000. GPC
The weight average molecular weight MW can be calculated by (gel permeation chromatography method) by Morio Tsuge, Tatsuya Miyabayashi and Masayuki Tanaka, "Journal of the Chemical Society of Japan", pages 800-805 (197).
According to the method described in (2 years), it can be performed by a method of leveling the peaks in the oligomer region (connecting the peaks and the center lines of the valleys).

Synthesis of polymer compound (2) 2-hydroxyethyl methacrylate 13.0 g, methacrylic acid 8.6 g, acrylonitrile 10.6 g, ethyl acrylate 60.0 g, and azobisisobutyronitrile 1.64 g were mixed with acetone. -Dissolve in 130 ml of a 1: 1 mixed solution of methanol and replace with nitrogen, and
Heated for hours.

Thereafter, 83 g of the polymer compound (2) was obtained in the same manner as the polymer compound (1).

When the molecular weight of this polymer compound (2) was measured by GPC, the weight average molecular weight was 67,000.
It was 0.

Synthesis of diazo resin 1 14.5 g of p-diazodifernylamine sulfate was dissolved in 40 g of concentrated sulfuric acid under ice cooling. To this reaction solution
05 g paraformaldehyde was added slowly. At this time, the reaction temperature was added so as not to exceed 10 ° C. Then, stirring was continued under ice cooling for 2 hours. The reaction mixture was added dropwise to 500 ml of ethanol under ice cooling, and the generated precipitate was filtered off. After washing the precipitate with ethanol,
This precipitate was dissolved in 100 ml of pure water, and this solution was added to 6.
An aqueous solution in which 8 g of zinc chloride was dissolved was added. The precipitate formed was filtered off, washed with ethanol and dissolved in 150 ml of pure water. An aqueous solution in which 8 g of ammonium hexafluorophosphate was dissolved was added to this solution, the resulting precipitate was filtered off, washed with water and ethanol, and then dried at 25 ° C. for 3 days to obtain diazo resin 1.

Synthesis of diazo resin 2 21.75 g of p-diazodifernylamine sulfate and 3.5 g of p-hydroxybenzoic acid were dissolved in 90 g of concentrated sulfuric acid under ice cooling. 2.7 g of paraformaldehyde was slowly added to the reaction solution. At this time, the reaction temperature was added so as not to exceed 10 ° C. Then 2
Stirring was continued under ice cooling for an hour. The reaction mixture was added dropwise to 1 liter of ethanol under ice cooling, and the generated precipitate was separated by filtration. After washing the precipitate with ethanol, the precipitate is washed with 200
It was dissolved in pure water (ml), and an aqueous solution in which 10.5 g of zinc chloride was dissolved was added to this solution. After filtering off the resulting precipitate,
It was washed with ethanol and dissolved in 300 ml of pure water. To this solution, an aqueous solution in which 13.7 g of ammonium hexafluorophosphate was dissolved was added, the resulting precipitate was filtered off, water,
After washing with ethanol, it was dried at 25 ° C. for 3 days to obtain diazo resin 2.

Next, examples will be described together with comparative examples. Examples-1 and 2 and Comparative Examples-1 and 2 Aluminum plates were desalted with a 10 wt% sodium hydroxide aqueous solution, and this was dewatered in a 1.8% hydrochloric acid bath at 25 ° C and 30 A /.
Electrolytic etching was performed under a current density condition of dm ² for 30 seconds, washed with water, and then anodized for 30 seconds in a 30% sulfuric acid bath at 30 ° C. and 6.5 A / dm ² . Next, a 1 wt% sodium metasilicate aqueous solution was used for sealing treatment at 85 ° C. for 30 seconds, followed by washing with water and drying to obtain an aluminum plate as a lithographic printing plate support.

The photosensitive solutions shown in Table 1 were applied to this aluminum plate so that the coating film weight after drying was 20 mg / dm ² , to prepare a photosensitive lithographic printing plate sample.

[Table 1]

A negative transparent original image is placed on the obtained sample and 2 k
After exposing with a metal halide lamp of W from a distance of 60 cm for 30 seconds, 27 using Konica PS plate automatic processor PSK-910 and Konica PS plate developer SDN-21 (4 times dilution) (both manufactured by Konica Corporation) Development processing was performed at 20 ° C. for 20 seconds.

The sensitivities of the respective samples were compared by the number of solid steps when exposure and development were performed using a Konica step tablet as an original image. In addition, the obtained plate is Konica PS gum liquid SG
After applying Q-3 (diluted 2 times) and drying, printing with Heidelberg GTO printing machine, the gum in the image area is removed,
The number of sheets required to obtain normal inking was compared, and the ink inking property was evaluated. The results are shown in Table 2.
Shown in.

[Table 2]

It can be seen from Table 2 that both Examples-1 and 2 have improved ink receptivity without lowering the sensitivity as compared with Comparative Example 2. On the other hand, in Comparative Example-1, it is found that the ink receptivity is improved but the sensitivity is lowered. Moreover, in Example-1,
Both ink receptivity and sensitivity are improved.

[0109]

As described above, according to the present invention, a photosensitive lithographic printing plate having good ink receptivity can be obtained without lowering the sensitivity.

Claims (1)

[Claims] 1. At least one polymer selected from the group consisting of polymer compounds represented by any of the following general formulas (1) to (4) on at least one surface of a support. A negative photosensitive lithographic printing plate having a photosensitive layer containing a compound and a diazo resin. [Chemical 1] In the general formulas (1) to (4), R ¹ , R ² , R ³ , ...,
R3 + a is a hydrogen atom, an alkyl group (including those having a substituent), or an aryl group (including those having a substituent). However, in each formula, not all hydrogen atoms are taken. A and B represent terminal groups. l, m, n, ...
.., n + a are numbers determined by the degree of polymerization in each formula. In the general formula (4), a is a number of 1 or more and 17 or less.