JPH024258A - Negative photosensitive printing plate - Google Patents

Abstract

PURPOSE:To obtain a negative type photosensitive printing plate having high sensitivity in a photosensitive layer, superior developability and durability for printing, as well as having superior printability for UV ink by incorporating a specified cocondensation diazo resin and a specified silane coupling agent in the photosensitive layer. CONSTITUTION:The title photosensitive printing plate contains a diazo resin consisting of an aromatic compd. having COOH group(s) and OH group(s), and an aromatic diazonium compds. as structural units. A silane coupling agent and/or a titan coupling agent is(are) contained together with the photosensitive diazo resin and a binder, wherein silane coupling agent is particularly preferred. Thus, a printing plate having superior developability, chemical resistance, and printability for UV ink is obtd.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a negative-working photosensitive printing plate, particularly a negative-working printing plate that has excellent chemical resistance, UV ink suitability, sensitivity, and developability in plate making and printing processes. Regarding photosensitive printing plates.

[Conventional technology]

Negative-working photosensitive lithographic printing plates generally have a photosensitive composition coated on a support such as an aluminum plate whose surface has been made hydrophilic, and when this is exposed to active light such as ultraviolet rays through a negative image, In the exposed area, polymerization or crosslinking occurs to form an insoluble and lipophilic film. On the other hand, by eluting the unexposed areas using a developer, the hydrophilic surface of the support is exposed. That is, an image area that repels water and receives ink and a non-image area that receives water and repel ink are obtained.

In this case, the photosensitive composition is particularly suitable for negative type 2
In the 8th edition, diazo resins such as the condensate of p-diazodiphenylamine and formaldehyde have been widely used.

In addition, using the high molecular weight condensed diazo resin
It is known from Japanese Patent Application Laid-Open No. 59-78340, and furthermore, it is also known from Japanese Patent Publication No. 49-48001 to use a diazo cocondensation resin.

On the other hand, in order to obtain a large number of printed materials on a single printing plate, the image area and the support are strongly bonded, and in order to improve the chemical resistance against various chemicals used in the plate-making process and the printing process. Furthermore, JP-A-59-192250 discloses providing a non-photosensitive intermediate layer containing a silane coupling agent between the support and the photosensitive layer.

[Problem to be solved by the invention]

However, when the above-mentioned condensed diazo resin is made to have a high molecular weight, although it becomes highly sensitive, it becomes poorly soluble in alkali, so the developability deteriorates inversely.

Further, although the above-mentioned co-condensed diazo resin has excellent developability, it has a drawback of low sensitivity.

On the other hand, when a non-photosensitive intermediate layer containing a silane coupling agent is provided between the support and the photosensitive layer as in JP-A-59-192250, there are drawbacks such as staining in non-image areas. be.

Therefore, the main object of the present invention is to provide a negative-working photosensitive printing plate that has high sensitivity in the photosensitive layer, excellent developability and stiffness resistance, good suitability for UV ink, and is free from stains in non-image areas. There is a particular thing.

[Means to solve the problem]

The above problem is achieved in a negative-working photosensitive printing plate having a photosensitive layer on a support; the photosensitive layer comprises (A) at least one organic group of at least one carboxyl group and at least one hydroxyl group; a co-condensed diazo resin containing an aromatic compound having an aromatic diazonium compound as a structural unit, (B) a silane cuff pulling agent, and at least one kind of camping agent among a titanium coupling agent. This can be solved.

[Specific structure of the invention]

The present invention will be described in further detail below.

In the present invention, the diazo resin is an aromatic compound having at least one organic group among at least one carboxyl group and at least one hydroxyl group;
A co-condensed diazo resin containing an aromatic diazonium compound as a constituent unit is used.

The aromatic compound having a carboxyl group and/or a hydroxyl group according to the present invention includes 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.

Preferable examples of the aromatic ring include aryl groups such as phenyl and naphthyl groups.

Furthermore, the above carboxyl group or hydroxyl group may be bonded directly to the aromatic ring or may be bonded via a joint.

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 to 3. Furthermore, examples of joints include alkylene groups having 1 to 4 carbon atoms.

Specific examples of aromatic compounds containing a carboxyl group and/or hydroxyl group that can be used in the present invention include benzoic acid, 0-di6-benzoic acid, m-chlorobenzoic acid, p-
Chlorobenzoic 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-methoxybenzoyl)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, phloroglycine, 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-probylsalicylic acid, 6-laurylsalicylic acid, 6-styarylsalicylic 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-dihydroxy4-benzoic acid, 4-chloro-2 , 6-dihydroxybenzoic acid, 4-methoxy-2,6-dioxybenzoic acid, gallic acid, phloroglucincarboxylic acid, 2,4.5 trihydroxybenzoic acid, m-galloyl gallic acid, tannic acid, m-benzoyl Gallic acid, m(p-toluyl) gallic acid, protocatechuo-gallic acid, 4,6-cyhydroxyphthalic acid, (2,4-dihydroxyphenyl)
Acetic acid, (2,6-dihydroxyphenyl)acetic acid, (3,
4,5-)dihydroxyphenyl)acetic acid, p-hydroxymethylbenzoic acid, p-hydroxyethylbenzoic acid H14
-(P-hydroxyphenyl)methylbenzoic acid, 4-(
〇-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-hydroxyphenylsulfonyl)benzoic M, 4-(p-hydroxyphenylthio)benzoic acid, etc. Among these, particularly preferred are salicylic acid, p-hydroxybenzoic acid, p-methoxybenzoic acid, and metachlorobenzoic acid.

For the aromatic diazonium compound of the present invention, diazonium salts such as those listed in Japanese Patent Publication No. 49-48001 can be used, but diphenylamine-4-diazonium salts are particularly preferred.

Diphenylamine-4-diazonium salts are derived from 4-amino-diphenylamines, such as 4-amino-diphenylamine, 4-amino-3-methoxy-diphenylamine, 4-amino-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-β-hydroxy-ethoxydiphenylamine, 4-amino-diphenylamine-2-sulfonic acid, 4-amino-diphenylamine-2-carboxylic acid, 4-amino-diphenylamine-2'carboxylic acid, etc. Among them, 3-methoxy-4-amino-diphenylamine and 4-amino-diphenylamine are particularly preferred.

The above co-condensed diazo resin is more preferably used in combination with a condensed diazo resin formed 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 9% by weight in the diazo resin.
The content is 5% by weight or less. The weight percent ratio of co-condensed diazo resin:condensed diazo resin is particularly preferably 30 to 70, near 0 to 30, for both sensitivity and developability.
It is.

The co-condensed diazo resin and condensed diazo resin of the present invention are
Known methods such as Photographic Science and Engineering (Photo, Sci,
, Eng.) Volume 17, Page 33, (1973),
U.S. Patent No. 2,063,631, U.S. Patent No. 2,679,4
According to the methods described in each specification of No. 98, diazonium salts, aromatic compounds having carboxyl and hydroxyl groups, and aldehydes, such as paraformaldehyde, acetaldehyde, benzaldehyde, or ketones, such as acetone and acetophenone, in sulfuric acid, phosphoric acid, or hydrochloric acid. It is obtained by polycondensation of

Furthermore, these aromatic compounds, aromatic diazo compounds, and aldehydes or ketones having carboxyl groups and/or hydroxyl groups in their molecules can be freely combined with each other, and two or more of each can also be mixed and co-condensed. It is possible.

The molar ratio of the aromatic compound having at least one of a carboxyl group and a hydroxyl group to the aromatic diazonium compound is 1:0.1 to 0.1=1; preferably 1:0.5 to 0.2: 1, more preferably 1:l to 0.
The ratio is 2:1. In this case, the molar ratio of the sum of aromatic compounds and aromatic diazonium compounds having at least one of a carboxyl group and a hydroxyl group to aldehydes or ketones is usually 1:0.6 to 1.2, preferably zo , 7 to 1.5, and reacted at a low temperature for a short time, for example, about 3 hours, to obtain a co-condensed diazo resin.

The counter anion of the diazo resin used in the present invention is
It contains an anion that stably forms a salt with the diazo resin and makes the resin soluble in an organic solvent.

These include organic carboxylic acids such as decanoic acid and benzoic acid, organic phosphoric acids such as phenylphosphoric acid, and sulfonic acids; typical examples include methanesulfonic acid, chloroethanesulfonic acid, dodecanesulfonic acid, benzenesulfonic acid. , toluenesulfonic acid, mesitylenesulfonic acid, and anthraquinonesulfonic acid, 2-hydroxy-4-
Aliphatic and aromatic sulfonic acids such as methoxybenzophenone-5-sulfonic acid, hydroxysulfonic acid, 4-acetylbenzenesulfonic acid, dimethyl-5-sulfoisophthalate, 2.2', 4.4'-tetrahydroxybenzophenone, Hydroxyl group-containing aromatic compounds such as 1,2,3-1-lyhydroxybenzophenone, 2,2',4-lyhydroxyhenzophenone, halogenated Lewis acids such as hexafluorophosphoric acid and tetrafluoroboric acid, Examples include peroxylic acids such as ClO4 and roa, but are not limited thereto. Among these,
Particularly preferred are hexafluorophosphoric acid and 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid.

The co-condensed diazo resin of the present invention can have any molecular weight by varying the molar ratio of each monomer and the condensation conditions; however, in order to effectively serve the purpose of the present invention, has a molecular weight of about 400 to, o
oo can be used, but preferably about 800
Suitable values are from s to ooo.

The photosensitive layer in the present invention includes the above photosensitive diazo resin,
At least one coupling agent selected from among a silane coupling agent and a titanium coupling agent is contained together with the binder described below.

As the camping agent, a silane coupling agent is particularly preferred, and this refers to a compound in which at least two reactive groups and/or atoms are bonded to a tetravalent silicon atom directly or via a linking group. Examples of reactive groups include amino groups, vinyl groups, and epoxyethyl groups (
CH, -CH-), \ 1 epoxyethylene group, (-CIl -CIl-), merka, 1 buto group, alkoxy group, alkyl group, acyloxy group,
Ammonium compound residues may be mentioned. Examples of the alkoxy group include those having 1 to 4 carbon atoms, such as a methoxy group and an ethoxy group.

Examples of the alkyl group include those having 1 to 4 carbon atoms, such as a methyl group and an ethyl group. Examples of the acyloxyl group include alkylcarbonyloxy groups having 2 to 4 carbon atoms, such as an acetyloxy group and a butyryloxy group. Examples of ammonium compound residues include quaternary ammonium compound residues such as octadecyldimethylammonium chloride residues.

These groups may have a substituent, and examples of groups having a substituent include α-methylvinyl group, β-methoxyethoxy group, anilino group, bis(β-hydroxyethyl)amino group, etc. .

Examples of the atom bonded to the silicon atom directly or via a linking group include a halogen atom such as a chlorine atom.

Examples of the above-mentioned linking group include alkylene groups having 1 to 5 carbon atoms such as ethylene, propylene, trimethylene, and tetramethylene groups, and carbon atoms such as trimethyleneoxymethylene and ethyleneoxyethylene groups. Alkyleneoxyalkylene groups having 2 to 8 carbon atoms, such as trimethyleneaminoethylene groups, alkyleneaminoalkylene groups having 2 to 8 carbon atoms, such as ethyleneoxycarbonyl groups, and trimethyleneoxycarbonyl groups; Alkyleneaminoalkyleneaminophenylene groups having 9 to 15 carbon atoms, such as 2 to 5 alkyleneoxycarbonyl groups (however, the alkylene group is directly bonded to the silicon atom), trimethyleneaminoethyleneaminomethylenephenylene groups; (However, the alkylene group is directly bonded to the silicon atom.). Further, the above-mentioned epoxyethyl group is bonded to a linking group and bonded to a silicon atom as an epoxycycloalkylalkyl group, such as a β-(3,4-epoxycyclohexylethyl group).

The silane coupling agent used in the present invention includes:
Furthermore, a disilazane compound such as hexaalkyldisilazane may also be contained.

Specific examples of the silane coupling agent include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, N-(2-aminoethyl)3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl)3-
Aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacrylic Examples include oxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-ureidopropyltriethoxysilane. In addition, as a titanium coupling agent,
Isopropyl triisostearoyl titanate, isopropyl tridodecylhenzensulfonyl titanate, isopropyl tri(dioctylpyrophosphate) titanate, tetraisopropyl bis(dioctyl phosphite) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2,2) Examples include -diallyloxymethyl-1-butyl)bis(ditridecylphosphite)titanate, bis(dioctylpyrophosphate)-oxyacetate titanate, and bis(dioctylpyrophosphate)ethylene thicnate.

Among the above-mentioned silane coupling agents, preferred in the present invention are those in which 2 to 3 alkoxy groups are directly bonded to a silicon atom, and a vinyl group is further bonded to a silicon atom via a linking group.

In the present invention, the silane coupling agent and/or the titanium coupling agent are usually contained in the photosensitive composition constituting the photosensitive layer at a ratio of o, oi to 5% by weight, particularly 0, 1 to 1.5% by weight. It is preferable to let

The photosensitive diazo cocondensation resin and coupling agent described above are preferably used in combination with an alkali-soluble (or swellable) lipophilic polymer compound as a binder resin.

As this lipophilic polymer compound, the following (1) to (2) are used.
Examples include copolymers whose structural units are the monomers shown below and which usually have a molecular weight of 20,000 to 200,000.

(1) Acrylamides, methacrylamides, acrylic esters, and methacrylic esters having an aromatic hydroxyl group, such as N-(4-hydroxyphenyl)
acrylamide or N-(4-hydroxyphenyl)methacrylamide, 0-m-, p-hydroxystyrene,
o-, m-, p-hydroxyphenyl-acrylate or methacrylate, (2) acrylic esters and methacrylic esters with aliphatic hydroxyl groups, such as 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate, (3) acrylics (4) Methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, 2-chloroethyl acrylate, glycidyl acrylate, N-
(Substituted) alkyl acrylates such as dimethylaminoethyl acrylate, (5) methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, cyclohexyl methacrylate, 4-hydroxybutyl methacrylate, glycidyl methacrylate, N-dimethylaminoethyl methacrylate, etc. (Substituted) alkyl methacrylate, (6) acrylamide, methacrylamide, N-methylol acrylamide, N-methylol methacrylamide, N-ethyl acrylamide, N-hexyl methacrylamide, N-cyclohexyl acrylamide, N-
Acrylamides or methacrylamides such as hydroxyethyl acrylamide, N-phenylacrylamide, N-nitrophenyl acrylamide, N-ethyl-N-phenylacrylamide, (7) ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, Vinyl ethers such as butyl vinyl ether, octyl vinyl ether, phenyl vinyl ether, (8) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl benzoate, etc. (9) Styrene, α-methylstyrene, methylstyrene, chloro Styrenes such as methylstyrene, 00) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, and phenyl vinyl ketone, Ql) Olefins such as ethylene, propylene, isobutylene, butadiene, and isoprene, (121N-vinylpyrrolidone) , N-vinylcarbazole, 4-vinylpyridine, acrylonitrile, methacrylatetrile, etc. Furthermore, monomers that can be copolymerized with the above monomers may be copolymerized.Also, copolymers obtained by copolymerization of the above monomers may be used, for example. , glycidyl methacrylate, glycidyl acrylate, etc., but are not limited to these.

More specifically, a copolymer having a hydroxyl group containing the monomers listed in (11 and (21) above is preferred, and a copolymer having an aromatic hydroxyl group is even more preferred.

The copolymer preferably contains an α,β-unsaturated carboxylic acid listed in (3), and the copolymer preferably has an acid value of 10 to 100.

The preferred molecular weight of the above copolymer is 40,000 to 150,000.

Further, polyvinyl butyral resin, polyurethane resin, polyamide resin, epoxy resin, novolac resin, natural resin, etc. may be added to the above copolymer as necessary.

This type of lipophilic polymer compound is usually 40 to 99% by weight, preferably 50 to 95% by weight in the solid content of the photosensitive composition.
Contain. Further, the photosensitive diazo resin used in the present invention is usually contained in an amount of 1 to 60% by weight, preferably 3 to 30% by weight.

On the other hand, particularly preferred as a binder are lipophilic polymer compounds having methyl acrylate as a structural unit. In this case, more preferred are the following copolymers.

That is, in the molecular structure, (a structural unit having an alcoholic hydroxyl group and/or
or 1 to 50 mol% of a structural unit having a phenolic hydroxyl group, (b) the following formula I, I ClI2 C'-'-・-・--IN (wherein R1 represents a hydrogen atom or an alkyl group) .) 5 to 40 mol% of structural units represented by fC) 5 to 40 mol% of units formed from methyl acrylate
, (dl The following formula ■, -CH2-C------------IfCOOR' (wherein, R2 represents a hydrogen atom, a methyl group, or an ethyl group, and R3 represents a carbon atom number of 2 ~12 alkyl groups or alkyl-substituted aryl groups.
It is a copolymer having a weight average molecular weight of 50,000 to 200,000.

Specific examples of the monomer forming the structural unit containing an alcoholic hydroxyl group include (meth)acrylic acid such as the compound shown in the following formula (I[[) as described in Japanese Patent Publication No. 52-7364. Examples include esters and acrylamides.

In the formula, R4 is a hydrogen atom or a methyl group, Rs is a hydrogen atom,
Methyl group, ethyl group or chloromethyl group, and n is 1
~Indicates an integer of IO.

Examples of (meth)acrylic acid esters include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 2-hydroxypentyl (meth)acrylate.
Examples of acrylamides include N-methylol(meth)acrylamide, N-
Examples include hydroxyethyl (meth)acrylamide. Preferably it is 2-hydroxyethyl (meth)acrylate.

In addition, examples of the seven polymers forming a structural unit having a phenolic hydroxyl group include N-(4-hydroxyphenyl)=(meth)acrylamide, N-(2-hydroxyphenyl)-(meth)acrylamide, N-( Monomers of (meth)acrylamides such as 4-hydroxynaphthyl)-(meth)acrylamide: o-, m-+ or p
-Hydroxyphenyl (meth)acrylate monomer:
Examples include Om- or halo-hydroxystyrene monomers. Preferably, o-, m- or p-hydroxyphenyl (meth)acrylate monomers, N-(4-hydroxyphenyl)-(meth)acrylamide monomers, more preferably 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 selected from the range of 1 to 50 mol%, preferably 5 to 30 mol%, in the polymer compound.

The monomers having a cyano group in the side chain and forming the structural unit represented by the above-mentioned formula (2) include acrylonitrile, methachloronitrile, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, o+ , m+, p-cyanostyrene, and the like. Preferred are acrylonitrile and methachloronitrile. The proportion of the structural unit having a cyano group in the side chain contained in the molecule of the polymer compound is selected from the range of 5 to 40 mol%, preferably 15 to 35 mol%.

The unit formed from methyl acrylate is 5 to 40 mol%, preferably 10 to 30 mol% in the polymer compound.
selected from the range.

Examples of the monomer having a carboxy ester group in the side chain and forming the structural unit represented by the formula (2) include ethyl acrylate, ethyl methacrylate, propyl acrylate, butyl acrylate, amyl acrylate,
amyl methacrylate, hexyl acrylate, octyl acrylate, 2-chloroethyl acrylate, 2-
Examples include hydroxyethyl acrylate, glycidyl acrylate, and the like. The unit formed from the monomer accounts for 25 to 60 mol%, preferably 3% by mole in the polymer compound.
It is selected from the range of 5 to 60 mol%.

Furthermore, examples of monomers forming structural units having carboxyl groups include methacrylic acid, acrylic acid, maleic anhydride, maleic acid, and the like. The monomer accounts for 2 to 30 mol%, preferably 5 to 15 mol% in the polymer compound.
Selected from the range of mol%.

Note that each of the above structural units is not limited to units formed from the monomers listed as specific examples.

As a method for synthesizing the polymer compound as a binder in the composition of the present invention, for example, using an initiator (0,1 ~4.0 mol%) by a solution polymerization method.

The molecular weight of the polymer compound is 50,000 to 200,000, preferably 8,000 to 200,000, and preferably 8,000 to 200,000. A range of 150,000 to 150,000 is used.

In addition to the components described above, the photosensitive composition used in the present invention may further include dyes, pigments, coating properties improvers,
Plasticizers and the like can be added.

Examples of the above-mentioned dyes include Victoria Pure Blue BOH (manufactured by Osugaya Kagaku Co., Ltd.) and Oil Blue #603 (
(manufactured by Orient Chemical Co., Ltd.), Patent Pure Blue (manufactured by Sumitomo Mikuni Chemical Co., Ltd.), Criscle Hiolesotho, Brilliant Green, Ethyl Violet, Methyl Green, Erythrosin B1 Basisofucsin, Malachite Green, Oil Red, m-Cresol Purple, Rhodamine B, triphenylmethane-based, diphenylmethane-based, oxazine-based, xanthine-based, iminonaphthoquinone-based, azomethine-based or Examples include anthraquinone dyes.

The dye is usually present in the photosensitive composition in an amount of about 0.5% to about IO% by weight.
, preferably about 1 to 5% by weight.

Examples of coating property improvers include alkyl ethers (e.g., ethyl cellulose, methyl cellulose), fluorine-based surfactants, and nonionic surfactants (e.g., Pluronic L-64 (manufactured by Asahi Denka)). Examples of plasticizers for imparting flexibility and wear resistance include butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, and tributyl phosphate. , trioctyl phosphate, tetrahydrofurfuryl oleate, and oligomers of acrylic acid or methacrylic acid. Examples of the oil-sensitizing agent for improving the oil-sensitivity of the image area include JP-A-55-527.
Examples of stabilizers include polyacrylic acid, tartaric acid, phosphoric acid, phosphorous acid, organic acids (acrylic acid, methacrylic acid, , citric acid, oxalic acid, benzenesulfonic acid, naphthalenesulfonic acid, 4-methoxy-2-hydroxybenzophenone-5
-sulfonic acid, etc.). The amount of these additives added varies depending on the purpose of use, but is generally 0.01 to 30% by weight based on the total solid content.

A photosensitive lithographic printing plate is obtained by applying the above photosensitive composition onto the surface of a support and drying it.

Examples of the coating solvent include cellosolves such as methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve, and ethyl cellosolve acetate, dimethyl formamide, dimethyl sulfoxide, dioxane, acetone, cyclohexanone, trichloroethylene, and methyl ethyl ketone.

These solvents may be used alone or in combination of two or more.

As the coating method, conventionally known methods such as spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating, curtain coating, etc. can be used. The amount of application is 0.2 to 1 Og/n based on solid content. is preferred.

It is preferable to use an aluminum plate as the support for the photosensitive lithographic printing plate of the present invention. The surface is grained by electrolytic roughening in nitric acid or an electrolytic solution containing nitric acid as a main component, or in hydrochloric acid or an electrolytic solution containing hydrochloric acid as a main component, preferably further anodized and sealed if necessary. Use one that has undergone surface treatment such as hole treatment.

Electrolytic surface roughening is carried out by immersing an aluminum plate in a bath containing 0.1 to 0.5 mol/l, preferably 0.2 to 0.4 mol/l of nitric acid or hydrochloric acid, and
Temperature of 0°C, preferably 25-40°C, current density of 20-40°C
It is preferable to perform electrolytic etching at 200 A/dm2 for about 10 seconds to 3 minutes. After this graining treatment, if necessary, a desmut treatment is performed with an aqueous alkali or acid solution to neutralize the material, and the material is washed with water.

The anodizing 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 electrolyte. The amount of anodic oxide film formed is 1 to 50 mg/d
m" is suitable, preferably 1O to 40 mg/dm"
It is. Here, the amount of anodized film is determined by, for example, replacing the aluminum solution with a phosphoric acid chromic acid solution (85% phosphoric acid aqueous solution 35II).
11 and 20 g of chromium oxide (Vl) dissolved in IIt water) to dissolve the oxide film, and measure the change in position before and after the film is dissolved.

Pore sealing treatments include boiling water treatment, steam treatment, sodium silicate treatment, dichromate aqueous solution treatment, and the like. In addition, water-soluble polymer compounds,
Subbing treatment can also be performed using an aqueous solution of a metal salt such as fluorinated zirconate.

The photosensitive lithographic printing plate thus obtained can be used by a known method. Typically, a negative film is brought into close contact with a photosensitive printing plate, exposed to light using an ultra-high pressure mercury lamp or a metal halide lamp, and developed using various known developers to obtain a printing plate. The lithographic printing plate produced in this way can be used in sheet-fed and off-wheel printing presses.

That is, by exposing through a transparent original with a line image, a halftone image lamp, and then developing with an aqueous developer,
A negative relief image is obtained for the original image. Light sources suitable for exposure include carbon arc lamps, mercury lamps, xenon lamps, metal halide lamps, strobes, and the like.

The developer used in the development of the photosensitive lithographic printing plate of the present invention may be any known developer, but examples include organic solvents such as benzyl alcohol and ethylene glycol monophenyl ether, and alkali metal silicate. and alkaline agents such as organic amine compounds, and those containing water as a main component, those that do not contain organic solvents, and anionic surfactants such as the above alkaline agents, higher alcohol sulfate ester salts and alkylaryl sulfonates. agent,
It is preferable to use one containing an organic carboxylic acid as a main component.

After the photosensitive lithographic printing plate of the present invention is imagewise exposed, if it is brought into contact with the above-mentioned developer or rubbed and rinsed, the photosensitive layer will be removed after 10 to 60 seconds at about 10 to 40 degrees Celsius. The photosensitive composition in the non-exposed areas is completely removed without adversely affecting the exposed areas.

〔Example〕

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples.

(Synthesis of co-condensed diazo resin) 3.5 g (0,025 mol) of p-hydroxybenzoic acid and 22.0 g (0,075 mol) of 4-diazo-4'-methoxydiphenylamine sulfate were mixed under water cooling with 9
Dissolved in 0g of concentrated sulfuric acid. After this reaction, 2.7 g of paraformaldehyde (0.09 mol) were added slowly. At this time, the addition was carried out so that the reaction temperature did not exceed 10°C. Thereafter, stirring was continued for 2 hours under water cooling. This reaction mixture was poured into 11 ethanol under water cooling, and the resulting precipitate was filtered.

After washing with ethanol, this precipitate was dissolved in 200 mj+ pure water, and a cold concentrated aqueous solution in which 10.5 g of zinc chloride was dissolved was added to this solution. The resulting precipitate was filtered, washed with ethanol, and dissolved in 30On11 pure water.

A cold concentrated aqueous solution containing 13.7 g of ammonium hexafluorophosphate was added to this solution. The resulting precipitate was filtered, washed with water, and then dried at 30°C for one day and night to obtain co-condensed diazo resin-1.

When the molecular weight of this co-condensed diazo resin-1 was measured by GPC, the weight average molecular weight was about 2,300.

Next, the aluminum plate was degreased with a 3% aqueous sodium hydroxide solution, and then heated at 25°C in a 2% hydrochloric acid bath at 3A/d.
After washing with water, anodizing was performed at 30°C for 2 minutes at 1.5A/dm'' in a 5.3% sulfuric acid bath.Next, a 1% aqueous sodium metasilicate solution was applied at 85°C.
The pores were sealed for 30 seconds and dried with hydroxide to obtain an aluminum plate for a lithographic printing plate.

A photosensitive lithographic printing plate sample was prepared by coating this aluminum plate with a photosensitive liquid having the following composition so that the film weight after drying was 1.1 g/rd.

Co-condensed diazo resin 1gH31P/
AN/HA/MAA copolymer 10g Jurimer AC-1OL (Nippon Pure Pharmaceutical Co., Ltd.) 0.6g
Victoria Pure Blue B OH 0.2 g (Odugaya Kagaku@) Silane coupling agent Listed in Table 1 Methyl cellosolve 150 g The proportions (shown in parentheses) and structural formula of the above copolymer are shown below.

Chapter 1 Table The film was immersed at 25°C for 40 seconds and developed by rubbing lightly with absorbent cotton.

The results are shown in Table 2.

Table 2 Note that Comparative Example 2 uses 1lyP/AN/
EA/MA/MA^ (10/25/15/4515) was used. In Comparative Example 3, a condensation resin of diphenylamine and paraformaldehyde (counter anion PF, -) was used instead of the cocondensation resin.

A negative original image and a step wedge (density difference 0.15) were placed on the obtained sample, and after exposure for 30 seconds from a distance of 60 cm using a 2 kW metal halide lamp, 5DN-21 developer (manufactured by Konica Corporation, diluted 1:3) was applied. ) Also, Table 3 shows the stains in the non-print areas when the dilution ratio of 5DN-21 was 1:11.

Further, the film was immersed in UV printing cleaning oil Tsurfit (manufactured by Clarei Sobrene Chemical Co., Ltd.) for 30 seconds, and the residual film rate of the remaining image area was measured, and the results were as shown in Table 5.

Table 5 ○... Not dirty at all ×... Dirty △... Slightly dirty These samples were immersed in Ultra Plate Cleaner for 1 hour to see how the printed areas were eroded. , as shown in Table 4.

Table 4 [Effects of the Invention] As described above, according to the present invention, a printing plate having excellent developability, chemical resistance, UV printability, etc. can be obtained.

○... has almost no change ×...The drawing area is removed.

Claims (1)

[Claims] (1) In a negative photosensitive printing plate having a photosensitive layer on a support; the photosensitive layer contains at least one organic group of (A) at least one carboxyl group and at least one hydroxyl group; a co-condensed diazo resin containing an aromatic diazonium compound as a constituent unit, and (B) at least one coupling agent selected from a silane coupling agent and a titanium coupling agent. A negative photosensitive printing plate.