JPH0490549A - Dampening waterless photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To obtain the printing plate which is not stained during printing, has excellent plate wear, is wide in developing latitude and has excellent dot reproducibility by incorporating a specific photosensitive compsn. into a primer layer and specifying the thickness thereof. CONSTITUTION:The primer layer is formed by incorporating at least one of (1) a diazo resin, (2) an ethylenic unsubstd. compd. having at least two polymerizable unsatd. groups in one molecule and (a) a photopolymn. initiator therein and the thickness of the primer layer is specified to >=6mu. This plate is required to be produced by a method of photocuring the primer layer provided on a base then applying a photosensitive layer and an ink repulsion layer in this order thereon. The material for the primer layer includes, for example, a polyester resin, vinyl chloride/vinyl acetate copolymer, acrylic resin, vinyl chloride resin, polyamide resin, polyvinyl butyral resin, etc. If the thickness of the primer layer is >=6mum, impact and galling are relaxed (cushioned) by the primer layer and the printing plate resistant to flawing is obtd.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a photosensitive lithographic printing plate that does not require dampening water, and more specifically, it is free from stains during printing, has excellent printing durability, and is easy to develop. The present invention relates to a photosensitive lithographic printing plate which has a wide latitude and excellent halftone dot reproducibility and does not require dampening water.

[Background of the Invention] Conventionally, photosensitive lithographic printing plates that do not require dampening water (hereinafter referred to as "one-plate material" if necessary) have been known to have a photosensitive layer and an ink-repellent layer coated on a support in this order. It is being By exposing and developing this plate material, a lithographic printing plate that does not require dampening water (hereinafter referred to as "printing plate" as necessary) can be obtained.

Generally, in such plate materials, a primer layer is provided between the support and the photosensitive layer in order to improve the adhesion between them.

Various materials are used for the primer layer, but
As an example, JP-A No. 60-229031 describes a photosensitive lithographic printing plate that does not require dampening water and uses a primer layer formed by photocuring a layer made of a photodimerizable photocurable resin. This indicates that the silicone rubber layer has excellent scratch resistance and abrasion resistance, and the resulting waterless plate has high printing durability.

Further, this primer layer has the advantage of good scratch resistance, especially resistance to scratches on the surface of the silicone rubber layer due to impact.

However, the primer layer used in this waterless plate has the advantage of good scratch resistance, especially the resistance to scratches on the surface of the silicone rubber layer due to impact, and has excellent printing durability. However, the resistance to scratches, such as those caused by brushes during development or plate cleaning cloth during printing, is not necessarily sufficient, and eventually stains occur during printing due to scratches caused by the latter, reducing printing durability. Problems arise.

There is also the problem that the development latitude is narrow, such as the halftone dot reproducibility varying depending on development conditions (for example, brush rubbing conditions, etc.).

Furthermore, JP-A-62-194255 describes the use of a primer layer with a thickness in the range of 6 to 100 μm, and it has been shown that this improves the scratch resistance of the silicone rubber layer. has been done.

However, although this waterless plate has improved scratch resistance on the surface of the silicone rubber layer due to impact, it does not suffer from scratches such as brushing during development or cleaning of the plate surface during printing. Resistance to scratches from cloth, etc. is not necessarily sufficient, and in the end, the latter may cause scratches and stains occur during printing, reducing printing durability and reducing halftone dot reproducibility depending on development conditions, resulting in narrow development latitude. I found out that there is also a problem.

Therefore, in view of the above-mentioned problems, the present inventors conducted various studies and found that the initial It was discovered that the object could be achieved, and the present invention was hereby accomplished.

[Purpose of the Invention] Therefore, the purpose of the present invention is to provide a photosensitive lithographic printing plate that does not require dampening water, has no stains during printing, has excellent printing durability, has a wide development latitude, and has excellent halftone dot reproducibility. It is about providing.

[Structure of the Invention] The object of the present invention is to provide a photosensitive lithographic printing plate that does not require dampening water and has a primer layer, a photosensitive layer, and an ink repellent layer in this order on a substrate, wherein the primer layer comprises (1) a diazo resin; (2) an ethylenically unsaturated compound having at least two polymerizable unsaturated groups in one molecule; and (3) at least one photopolymerization initiator, and the primer layer has a thickness of 6μ or more. This was achieved with a photosensitive lithographic printing plate that does not require dampening water.

Below, the configuration of the present invention will be explained in more detail.

The present invention maintains printing durability and developability by containing a diazo resin and a photopolymerizable photosensitive composition in the primer layer of a photosensitive lithographic printing plate that does not require water, and making the thickness 6μ or more. A wide latitude and excellent halftone dot reproducibility can be obtained.

The water-free photosensitive lithographic printing plate used in the present invention can also be used in a type in which only the silicone rubber layer in the image area is removed after development, but preferably the photosensitive layer in the image area is removed after development. A type that can be removed to expose the primer layer in the image area is preferable.

The method for producing the plate material used in the present invention requires that after photocuring a primer layer provided on a support, a photosensitive layer and an ink repellent layer are sequentially applied.

Examples of the primer layer used in the present invention include polyester resin, vinyl chloride-vinyl acetate copolymer, acrylic resin, vinyl chloride resin, polyamide resin, polyvinyl butyral resin, epoxy resin, acrylate copolymer, and vinyl acetate copolymer. Examples include polymers, phenoxy resins, polyurethane resins, polycarbonate resins, polyacrylonitrile butadiene, polyvinyl acetate, and the like.

In addition, as the anchor agent constituting the primer layer,
For example, silane coupling agents, silicone primers, etc. can be used, and organic titanates and the like are also effective.

The thickness of the primer layer described above is preferably 6 μm or more, particularly preferably 6 μm to 50 μm.

If the thickness of the primer layer is 6 μm or less, the silicone rubber layer will be damaged if it is subjected to impact with a hard object or rubbed with a developing brush, cloth, etc.

On the other hand, if the thickness is 6 μm or more, the above-mentioned impact or rubbing is alleviated by the primer layer (cushioning effect), making it difficult to damage.

The photosensitive composition contained in the primer layer used in the present invention will be specifically explained.

(1) Photosensitive composition containing diazo resin The diazo resin used in the present invention includes various types, but is preferably a diazo resin typified by a condensate of p-diazodiphenylamine and formaldehyde,
Those which are water-insoluble and soluble in organic solvents, preferably those described in Japanese Patent Publication No. 47-1167 and Japanese Patent Publication No. 57-43890, are water-insoluble and soluble in ordinary organic solvents. Particularly preferably, the following general formula [I
] It is a diazo resin shown by.

- Formula [I] [In the formula, RI R2 and R3 represent a hydrogen atom, an alkyl group, or an alkoxy group, and R4 represents a hydrogen atom, an alkyl group, or a phenyl group.

X represents PFa or BF4, and Y represents -NH--3- or -0-. Examples of the diazo monomer in the diazo resin used in the present invention include 4-diazo-diphenylamine, 1
-Diazo-4-N,N-dimethylaminobenzene, 1-
Diazo-4-N, N-diethylaminobenzene, 1-diazo-4-N-ethyl-N-hydroxyethylaminobenzene, 1-diazo-4-N-methyl-N-hydroxyethylaminobenzene, 1-diazo-2 , 5-jethoxy-4-benzoylaminobenzene, 1-diazo-4-
N-benzylaminobenzene, l-diazo-4-N,N
-dimethylaminobenzene, 1-diazo-4-morpholinobenzene, l-diazo-2,5-dimethoxy-4-p
-Tolylmercaptobenzene, 1-diazo-2-ethoxy-4-N,N-dimethylaminobenzene, p-diazodimethylaniline, 1-diazo-2,5-dibutoxy-4-morpholinobenzene, 1-diazo- 2,5-jethoxy-4-sulfolinobenzene, 1-diazo-2,5
-dimethoxy-4-morpholinobenzene, ■-diazo2.5-jetoxy4-p-tolylmercaptobenzene, 1-diazo-4-N-ethyl-N-hydroxyethylaminobenzene, 1-diazo-3-ethoxy-4 -N
-Methyl-N-benzylaminobenzene, 1-diazo-
3-chloro-4-N,N-diethylaminobenzene, 1
-Diazo-3-methyl-4-pyrrolidinobenzene, 1-
Diazo-2-chloro-4-N,N-dimethylamino-5
-methoxybenzene, 1-diazo-3-methoxy-4-
Examples include pyrrolidinobenzene, 3-methoxy-4-diazodiphenylamine, 3-ditoxy-4-diazodiphenylamine, 3-(n-propoxy)-4-diazodiphenylamine, 3-(isopropoxy)-4-diazodiphenylamine, etc. It will be done.

Examples of the aldehyde used as a condensing agent with the diazo monomer include formaldehyde, adetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, and benzaldehyde.

Furthermore, water-soluble diazo resins can be obtained by using chloride ions, tetrachlorozinc acid, etc. as anions, and boron tetrafluoride, hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid, 4.4' -biphenyldisulfonic acid, 2,5-dimethylbenzenesulfonic acid,
By using 2-nitrobenzenesulfonic acid, 2-methoxy-4-hydroxy-5-benzoyl-benzenesulfonic acid, etc., an organic solvent-soluble diazo resin can be obtained. Particularly preferably, a diazo resin made of hexafluorophosphoric acid is used.

The diazo resin is preferably used in combination with a film-forming resin, particularly a lipophilic polymer compound having a hydroxyl group. Such lipophilic polymer compounds include monomers having aliphatic hydroxyl groups in their side chains, such as copolymers of 2- and droxyethyl acrylate or 2-hydroxyethyl methacrylate and other copolymerizable monomers. can be mentioned. In addition to these, polyvinyl butyral resin, polyurethane resin, polyamide resin, epoxy resin,
Novolak resin, natural resin, etc. may be added.

In addition, various polymer compounds can be used as the binder used in combination with the diazonium salt, but preferably,
A monomer having an aromatic hydroxyl group as described in Japanese Patent No. 4-98613, such as N-(4-hydroxyphenyl)acrylamide, N-(4-hydroxyphenyl)methacrylamide, o+, m+, or p - copolymers of hydroxystyrene, o-, m+, or p-hydroxyphenyl methacrylate, etc., with other monomers, hydroxyethyl acrylate units as described in U.S. Pat. No. 4,123,276; or polymers containing hydroxyethyl methacrylate units as the main turning unit, natural resins such as shellac and rosin, polyvinyl alcohol, polyamide resins described in U.S. Pat. No. 3,751,257, and U.S. Pat.
．． 860,097, linear polyurethane resins, polyvinyl alcohol phthalate resins, epoxy resins condensed from bisphenol A and epichlorohydrin, alkali-soluble resins such as novolac resins, and vinyl-based resins having phenolic hydroxyl groups. Examples include polymers, condensation resins of polyhydric phenols and aldehydes or ketones described in JP-A-55-57841, and the like. Examples of the novolac resin include phenol-formaldehyde resin, cresol-formaldehyde resin, phenol-cresol-formaldehyde copolycondensation resin as described in JP-A-55-57841, and phenol-cresol-formaldehyde copolycondensation resin as described in JP-A-55-127553. Examples include copolycondensation resins of p-substituted phenol and phenol or cresol and formaldehyde as described above.

In addition to the above-mentioned materials, these photosensitive compositions may also contain colorants such as dyes and pigments, sensitizing agents, plasticizers, surfactants, organic acids, acid anhydrides, and acids that can be removed by exposure to light. Compounds that may be generated can be added.

These binders are present in an amount of 10 to 95% in the solid content of the photosensitive composition.
It is contained in an amount of 40 to 80% by weight. The diazo resin is contained in an amount of 5 to 80% by weight, preferably 15 to 60% by weight.

Other dyes, pigments such as pigments, fat-sensitizing agents, plasticizers, surfactants, etc. can be added to these photosensitive compositions.

(2) Photopolymerizable composition comprising an addition polymerizable unsaturated compound This composition preferably comprises (a) a vinyl monomer having at least two terminal vinyl groups, (b) a photopolymerization initiator, and ( C) Consists of a polymer compound as a binder.

The vinyl monomer of this component (a) is
No. 5093, No. 35-14719, No. 44-2872
It is described in each publication No. 7.

Acrylic or methacrylic esters of polyols, such as diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, or methylene bis(meth)acrylamide , bis(meth)acrylamides such as ethylene bis(meth)acrylamide, or unsaturated monomers containing urethane groups, such as di(2'-methacryloxyethyl)-2,4-)
- lylene diurethane, di(2-acryloxyethyl)
Examples include reaction products of diol mono(meth)acrylates and diisocyanates, such as trimethylene diurethane.

As the photopolymerization initiator of the component (b), for example, J,
"Light Sensitive Systems" by Kosar
Examples include carbonyl compounds, organic sulfur compounds, perfusate compounds, redox compounds, azo and diazo compounds, halogen compounds, and photoreducible dyes as described in the 5th article. More specifically, it is disclosed in British Patent No. 1,459,563.

Furthermore, various known polymers can be used as the binder for component (C). Details of specific binders are described in US Pat. No. 4,072,527.

These photopolymerizable compositions contain thermal polymerization inhibitors, plasticizers,
It can contain dyes, pigments, etc.

A liposensitizing agent and a surfactant added to the photosensitive composition,
The amount of additives such as sensitizers, stabilizers, thermal polymerization inhibitors, plasticizers, and pigments such as dyes and pigments varies depending on the type, but in general, they are included in the photosensitive composition contained in the photosensitive coating liquid. 0.01 to 20% by weight, preferably 0.05 to 20% by weight based on the product
10% by weight is suitable.

The amount of the photosensitive composition contained in the primer layer is 60% to 100% by weight, preferably 70% to 90% by weight, based on the primer layer.

Examples of the photosensitive layer that can be used in the present invention include, in the case of a positive type, a photopolymerizable adhesive layer or a photocrosslinkable photosensitive layer, a photosensitive layer made of a diazo resin, a binder resin, and the like. In the case of a negative type, a photosensitive layer made of a quinonediazide compound, a binder resin, etc. can be used.

Various conventionally known diazo resins can be used as the above-mentioned diazo resin, but include diazo resins typified by condensates of aromatic diazonium salts and active carbonyl-containing compounds, especially formaldehyde, among which diazo resins soluble in organic solvents are used. Resins are preferred.

Preferred specific examples of the diazo resin include resins represented by the following formula [I].

- Formula [I] [In the formula, R12R'' and R'' each represent a hydrogen atom, an alkyl group, or an alkoxy group, preferably a hydrogen atom. R'5 represents a hydrogen atom, an alkyl group or a phenyl group, preferably a hydrogen atom. X represents a counter anion of the diazo resin, specifically, PFa, BF4
, organic carboxylic acids such as decanoic acid and benzoic acid, organic phosphoric acids such as phenylphosphoric acid, and sulfonic acids such as methanesulfonic acid. Y represents NH% S10. Further, Z is at least one or more groups selected from a sulfonic acid group, a sulfonate group (Na salt, K salt, etc.), a sulfine group, a sulfinate group (Na salt, K salt, etc.), an OH group, and a COOH group. Represents a phenyl group or naphthyl group substituted with a substituent. The ratio of m and n is m/n=11 in molar ratio.
The range is 0 to 1o, preferably 170 to 2. The diazo resin represented by formula [I] above preferably has a molecular weight of about 500 to 10,000.

The content of diazo resin in the photosensitive layer is preferably 1 to 70
It is selected from the range of 3% to 60% by weight, more preferably 3% to 60% by weight.

Orthoquinone diazide compounds are used in negative-working photosensitive lithographic printing plates that do not require dampening water, and examples of such compounds include polycondensation resins of phenols and aldehydes or ketones and the following formula [+1] or general formula [ I
Examples include orthoquinonediazide sulfonic acid esters or carboxylic acid esters obtained by chemically condensing orthoquinonediazide sulfonic acid or carboxylic acid esters represented by II].

General formula [■ General formula [II+] (In the formula, X is a group represented by -502Y or -CoY, and Y represents a group that can be removed during condensation of a halogen atom, an alkali metal, etc.) The above general formula Specific examples of the compound represented by [II] include 1,2-benzoquinonediazide (2)-4-sulfonyl chloride, 1,2-benzoquinonediazide (2)-
Examples thereof include 4-carbonyl chloride, 1°2-benzoquinonediazide (2)-5-sulfonyl chloride, and 1,2-benzoquinonediazide (2)-5-carbonyl chloride.

Specific examples of the compound represented by the above general formula [II+] include 1,2-naphthoquinonediazide (2)-4-sulfonyl chloride, 1,2-naphthoquinonediazide (2)
-4-carbonyl chloride, 1,2-naphthoquinone diazide (2)-5-sulfonyl chloride, 1,2-naphthoquinone diazide (2)-5-carbonyl chloride, and the like.

Examples of polycondensation resins of phenols and aldehydes or ketones include polycondensates of pyrogallol and acetone as described in Japanese Patent Publication No. 43-28403, and polycondensates of pyrogallol and acetone as described in Japanese Patent Publication No. 55-76346. As described in Irugoto, a polycondensate of a mixture of pyrogallol and resorcin and acetone, as described in Japanese Patent Publication No. 45-9610, phenol formaldehyde novolak resin or metacresol formaldehyde novolac resin, Japanese Patent Publication No. 50-5083 Para-substituted phenol formalin resins (e.g. para-cresol formalin resin, para-t-butylphenol formalin resin, para-ethylphenol formalin resin, parapropylphenol formalin resin, paraisopropylphenol formalin resin) , para-herbylphenol/formalin resin, para-octylphenol/formalin resin, etc.), Special Publication 1986
Phenol containing a phenol substituted with an alkyl group or a phenyl group having 3 to 12 carbon atoms and phenol or its methyl substituted product or a mixture thereof in a molar ratio of 1:9 to 9:1, as described in Publication No. -60407. Polycondensates of formaldehyde and formaldehyde mixtures (for example, polycondensates of the para-substituted phenol and phenol, vala-cresol, metacresol, etc.) can be mentioned.

The esterification rate of the orthoquinone diazide group to the hydroxyl group of the polycondensation resin of phenols and aldehydes or ketones is preferably 15 to 100 mol%, and 20 to 80 mol%.
Mol% is more preferred.

Furthermore, as an orthoquinonediazide compound, orthonaphthoquinonediazide sulfonic acid ester of polyhydroxybenzophenone (for example, 1,2-naphthoquinonediazide (
2)-5-sulfonic acid ester, 1,2-naphthoquinonediazide (2)-4-sulfonic acid ester, etc.).

This polyhydroxybenzophenone is a compound obtained by replacing two or more hydrogen atoms of benzophenone with hydroxyl groups, such as dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, pentahydroxybenzophenone, octahydroxybenzophenone, or derivatives thereof (for example, , a halogen atom, an alkyl group, an aryl group, an aralkyl group, a substituent for a carboxylic acid group), and the like. Preferred are trihydroxybenzophenone or tetrahydroxybenzophenone, and more preferred are 2°3.4-trihydroxybenzophenone and 23.4.4'-tetrahydroxybenzophenone.

In addition, the esterification rate for hydroxyl groups is 30 to 100%.
is preferred.

In the present invention, each of the above compounds may be used alone as the orthoquinone diazide compound, or two or more thereof may be used in combination.

Among these orthoquinonediazide compounds listed above, 2,3,4-trihydroxybenzophenone 1.
2-naphthoquinonediazide (2)-5-sulfonic acid ester or 1,2-naphthoquinonediazide (2)-4-
Sulfonic acid ester, 1,2-naphthoquinone diazide of metacresol formaldehyde novolac resin (
2)=5-sulfonic acid ester or 1,2-naphthoquinonediazide (2)-4-sulfonic acid ester, or a mixture thereof is more preferably used.

The proportion of the above-mentioned orthoquinonediazide compound in the photosensitive layer is preferably 5 to 60% by weight, more preferably 20 to 60% by weight.
It is 50% by weight.

Further, examples of binder resins used in the photosensitive layer include acrylic resins and novolak resins. As a copolymerization component of acrylic resin, there are several copolymerizable components.
Any of them can be used, and in particular, the following compounds having an unsaturated bond are used as monomers for radical polymerization.

(1) Monomers having hydroxyl groups: 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxypentyl (meth)acrylate, 4-hydroxyphenyl (meth)acrylate, 2-hydroxyphenyl ( (Meth)acrylate monomers such as meth)acrylate; N-methylol (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, N-(hydroxyphenyl)-(meth)acrylamide, N-(hydroxynaphthyl)-(meth) ) (meth)acrylamide monomers such as acrylamide; 20-1m-1p-hydroxystyrene monomers; (2) (meth)acrylic acid ester or amide monomers other than (1); methyl (meth)acrylate, ethyl ( meth)acrylate, propyl(meth)acrylate, butyl(meth)acrylate
Alkyl (meth)acrylates such as acrylate; N
-Phenyl (meth)acrylamide, o-, m-5p-
Methoxyphenyl (meth)acrylamide, o-, m-
1p-ethoxyphenyl (meth)acrylamide, etc., (3) Chimers having a cyan group in the side chain; (meth)acrylonidonitrile, 2-pentenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, 0-1m-1p-cyanostyrene, etc. (4) Chimers having carboxylic acid in the side chain: (meth)
Acrylic acid, itaconic acid and its anhydride, maleic acid and its anhydride, crotonic acid, etc. (5) Vinyl ethers: probyl vinyl ether, butyl vinyl ether, octyl vinyl ether, phenyl vinyl ether, etc. (6) Styrene: α-methyl Styrene, methylstyrene, chloromethylstyrene, styrene, etc. (7) Vinyl ketones; Methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, etc. (8) Thousands of polymers other than (1) to (7): ethylene, propylene , isobutylene, butadiene, olefins such as vinyl chloride, N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, etc., and other olefins that can undergo radical copolymerization with these polymers. good.

In the present invention, in addition to the above-mentioned materials, the photosensitive layer may also include dyes, pigments, coating properties improvers, plasticizers, fat-sensitizing agents, stabilizers, etc. A curing agent etc. can be added. It is advantageous for the photosensitive layer of the positive type photosensitive lithographic printing plate that does not require dampening water to further contain a known exposure-visible image imparting agent.

Examples of the above dyes include Victoria Pure Blue BOH, Oil Blue #603, and Oil Pink #312.
, patent pure blue crystal violet, leuco crystal violet, brilliant green,
Ethyl violet, methyl green, erythrosin B
1Basic Tsuksin, malachite green, leucomalachite green, m-cresol purple, cresol red, xylenol blue Examples include phenylmethane-based, diphenylmethane-based, oxazine-based, xanthine-based, iminonaphthoquinone-based, azomethine-based, and anthraquinone-based dyes.

The dye is generally contained in the photosensitive layer in an amount of 0.01 to about 10% by weight, preferably about 0.05 to 8% by weight.

Examples of the coating property improver include alkyl ethers (eg, ethyl cellulose, methyl cellulose), fluorine-based surfactants, nonionic surfactants (eg, Pluronic L64 (manufactured by Asahi Denka)), and the like.

Examples of plasticizers for imparting flexibility and abrasion resistance to the coating include butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, Examples include toptyl phosphate, trioctyl phosphate, tetrahydrafurfuryl oleate, and oligomers of acrylic acid or methacrylic acid.

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.
Weight percent is preferred.

The thickness of the photosensitive layer used in the present invention is usually 0.2 to 100.
μm1 is preferably 0.5 to 20 μm.

In the present invention, a silicone rubber layer is coated on the photosensitive layer. The silicone rubber used in the silicone rubber layer of the present invention is preferably cotton-like or crosslinked polyorganosiloxane to some extent.

The polyorganosiloxane usually has a molecular weight of 1 to 10 yen, and is suitably crosslinked in the form of a liquid, wax, or cake at room temperature.

The polyorganosiloxane is classified into condensed type and addition type depending on the method of crosslinking.

In the condensed type, crosslinking is performed by a condensation reaction, and water, alcohol, organic acid, etc. are released as a result of the reaction. Particularly useful condensation type silicone rubbers include mixtures of linear polyorganosiloxanes having hydroxyl groups, acetoxy groups, etc. at both ends or in a part of the main chain, and silicone crosslinking agents;
Examples include those in which hydroxyl groups are reacted with a silicone crosslinking agent, and in any case, adding a condensation catalyst is advantageous in terms of crosslinking speed.

The main chain of the polyorganosiloxane has the following repeating units.

R.

1%5i-0) In the formula, R and R7 are an alkyl group, an aryl group, an alkenyl group, each of which may have a substituent, or a combination thereof; A group is preferred, and a methyl group is particularly preferred.

The above-mentioned silicone crosslinking agents include so-called acetic acid-removal type, oxime-removal type, alcohol-removal type, deamination type, which have a functional group represented by -OH (in the formula, R and R' are alkyl groups); Examples include pure mold silicone crosslinking agents such as dehydrated types. Examples of such crosslinkers include tetraacetoxysilane, methyltriacetoxysilane, ethyltriacetoxysilane, phenyltriacetoxysilane, dimethyldiacetoxysilane, diethyldiacetoxysilane, vinyltriacetoxysilane, methyltrimethoxysilane, dimethyl Dimethoxysilane, vinyltrimethoxysilane, methyltris(acetoneoxime)silane, methyltri(N-methyl-N-
Examples include acetylamino)silane, vinyltri(methylethylketoxime)silane, methyltri(methylethylketoxime)silane, and oligolimers thereof.

These crosslinking agents are all polyorganosiloxane 1
The amount is preferably in the range of 0.5 to 30 parts by weight per 00 parts by weight.

Examples of the condensation catalyst include organic carboxylic acids, titanate esters, acetylacetone metal complexes, chloroplatinic acid, naphthenic acid, and the like.

The addition type refers to an unsaturated group in the main body, such as a vinyl group (-C
H=CH2) is crosslinked by the addition of a water-based group in a crosslinking agent.

Specifically, examples include vinyl group-containing organopolysiloxanes, hydrogenated organopolysiloxanes, and the like mixed with platinum-based catalysts (for example, chloroplatinic acid).

The polyorganosiloxane has repeating units similar to those of the condensed type in the main chain.

In the silicone rubber layer of the present invention, either or both of condensation type and addition type silicone rubber can be used.

It is also possible to use integrated and addition type polyorganosiloxanes having hydroxyl groups, unsaturated groups, etc. in one polyorganosiloxane.

In the present invention, an adhesive layer made of acrylic resin or the like may be provided between the photosensitive layer and the silicone layer, and the adhesive layer may also contain various reactive crosslinking agents, silane coupling agents, etc. , and the thickness of the adhesive layer is 0.1 m.
g/dm2-5 B/dm' is preferred.

As the substrate that can be used in the present invention, any substrate can be used as long as it has the flexibility to be set in a normal lithographic printing machine and can withstand the load applied during printing, and there are no particular restrictions on the layer structure. Examples include papers such as coated paper, metal plates such as aluminum plates, and plastic films such as polyethylene terephthalate.

In particular, an aluminum plate or a composite material of aluminum foil and other materials is preferable, and from the viewpoint of printing durability, an aluminum plate is particularly preferable.

In addition, from the viewpoint of storage stability, the substrate, particularly an aluminum plate, or a composite material of aluminum foil and other materials, can be surface-treated by a known method before use.

Such surface treatment includes, for example, a method of treating the surface of an aluminum plate with silicate (U.S. Pat. No. 2,714).
, 066), a method of treatment with organic acid salts (U.S. Patent No. 2
, 714,066), methods of treatment with phosphonic acids and their conductors (U.S. Pat. No. 3,220,832)
, a method of treatment with potassium hexafluorozirconate (
(U.S. Pat. No. 2,946,683), a method of anodizing, and a method of treating with an aqueous solution of an alkali metal silicate after anodizing (U.S. Pat. No. 3,181,461).

Such a support is provided with a primer layer and then a photosensitive layer in order to obtain sufficient adhesion between the photosensitive layer and the support.

The thickness of each layer constituting the plate material of the present invention is as follows. That is, the support has a thickness of 50 to 400 μm, preferably 100 μm.
~300 μm 1 photosensitive layer 0.05-10 μm, preferably 0.1-1.0 μm, silicone rubber layer 0.5-10 μm
100 μm, preferably 1-4 μm. The primer layer has a thickness of 0.1 to 20 μm, preferably 0.3 to 10 μm.

In the present invention, a protective layer may be provided on the upper surface of the silicone rubber layer, if necessary.

The plate material of the present invention that does not require dampening water is manufactured, for example, as follows.

A composition solution to form a primer layer is applied onto a support using a conventional coater such as a reverse roll coater, an air knife coater, a Meyer bar coater, or a rotary coating device such as a Whaler, and is dried and crosslinked to cure. Next, a composition solution to form a photosensitive layer is applied and dried.

A silicone rubber solution is applied on the photosensitive layer in the same manner, and heat-treated at a temperature of usually 100 to 120°C for several minutes.
Fully cure to form a silicone rubber layer. If necessary, a protective film can be provided on the silicone rubber layer using a laminator.

Next, a method for manufacturing a printing plate that does not require dampening water using the plate material that does not require dampening water of the present invention will be explained.

A positive film, which is an M draft, is vacuum-adhered to the surface of the positive plate material and exposed. As a light source for this exposure, a mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, a fluorescent lamp, etc., which generate abundant ultraviolet rays, are used.

Next, the positive film is peeled off and developed using a developer. As the developer, any known developer can be used for plate materials that do not require dampening water, but preferably an aqueous developer is used.

The aqueous developer is a developer containing water as a main component, such as those described in Japanese Patent Laid-Open No. 61-275759, etc., which contain water in an amount of 30% by weight or more, preferably 50% by weight to 9% by weight.
Examples include a developer containing 8% by weight of an organic solvent and a surfactant, and more preferably an alkali agent.

Organic solvents contained in water-based developers include:
For example, aliphatic hydrocarbons (hexane, heptane, 'alcohols H, G' (manufactured by Esso Chemical Co., Ltd., product name of aliphatic hydrocarbons), gasoline, kerosene, etc.), aromatic hydrocarbons (toluene, etc.), , xylene, etc.), or halogenated hydrocarbons (triclene, etc.), alcohols (methanol, ethanol, 1-butoxy-2-propanol, 3-methyl-3-methoxybutanol, β-anilinoethanol, benzyl alcohol) etc.), ethers (methyl cellosolve, ethyl cellosolve, butyl cellosolve, phenyl cellosolve, methyl calpitol, ethyl calpitol, butyl calpitol,
dioxane, diethylene glycol dimethyl ether,
Diethylene glycol diethyl ether, diethylene glycol dibutyl ether, ethylene glycol dibutyl ether, propylene glycol, dipropylene glycol butyl ether, tripropylene glycol methyl ether, polypropylene glycol methyl ether, etc.), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, 4- methyl-1,3-dioxolan-2-one, etc.), esters (
ethyl acetate, propyl acetate, hexyl acetate, methyl acetate, propyl acetate, diethyl succinate, dibutyl oxalate, diethyl maleate, benzyl benzoate, methyl cellosolve acetate, cellosolve acetate, carpitol acetate, etc.).

As the surfactant added to the developer of the present invention, anionic surfactants, nonionic surfactants, cationic surfactants and amphoteric ionic surfactants are used, and specific examples include the following.

Examples of anionic surfactants include (1) higher alcohol sulfate esters (e.g. sodium salt of lauryl alcohol sulfate, ammonium salt of octyl alcohol sulfate, ammonium salt of lauryl alcohol sulfate, sulfonic sodium alkyl sulfate, etc.) (2) Fat Group alcohol phosphate ester salts (e.g.
(3) Alkylaryl sulfonates such as sodium dodecylbenzenesulfonate, isopropylnaphthalenesulfonate sodium salt, dinaphthalenesulfonate sodium salt, metanitrobenzenesulfonate sodium salt, etc.) 4) Alkylamide sulfonate salts (CryH55CON-CH2CH2SO3Na etc.) H
3 (5) Sulfonic acid salts of dibasic aliphatic esters (e.g., dioctyl sodium sulfosuccinate, dihexyl sodium sulfosuccinate, etc.) (6) Formaldehyde condensates of alkylnaphthalene sulfonates (e.g., sodium dibutylnaphthalene sulfonate) formaldehyde condensates, etc.).

Examples of nonionic surfactants include polyoxyerylene alkyl ether, polyocoxyethylene alkylphenol ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, glycerin fatty acid ester, oxyethylene oxypropylene block polymer, etc. It will be done.

Examples of the cationic surfactant include alkylamine salts, quaternary ammonium salts, polyoxyethylene alkylamines, and the like.

Examples of amphoteric surfactants include alkyl betaines, but among these, anionic surfactants are commonly used.

These surfactants can be used alone or with 2f! The above can be used in combination.

The appropriate amount of the surfactant used in the present invention is 0.01% to 60% by weight, preferably 0.1% to 10% by weight.

Further, the surfactant used in the present invention is preferably used together with an alkaline agent, and the alkaline agents include (1) sodium silicate, potassium silicate, potassium hydroxide, sodium hydroxide, lithium hydroxide, or inorganic alkaline agents such as trisodium or ammonium phosphate, sodium metasilicate, sodium carbonate, ammonia, (2) mono, di or trimethylamine, mono, di or triethylamine, mono or diisopropylamine, n-butylamine, mono, Examples include organic amine compounds such as di- or triethanolamine, mono-, di- or triisopropanolamine, ethyleneimine, and ethylenediimine.

The amount of alkaline agent used is 0.05% to 20% by weight,
Preferably, 0.2% to 10% by weight is appropriate.

It is also possible to dye the image area simultaneously with development by adding a dye such as crystal violet or astrazonelet to the developer.

Development can be carried out, for example, by rubbing the above-mentioned developer with a developer-containing pad, or by pouring the developer onto the printing plate and then rubbing it with a developer brush.

By the above development, a printing plate is obtained in which the photosensitive layer and silicone rubber in the unexposed areas are removed, or a printing plate in which the silicone rubber layer is removed, the photosensitive layer is exposed, and the silicone rubber layer remains in the exposed areas.

Example-1 Synthesis of Diazo Resin-1 14.5 g (50 mmol) of p-diazodiphenylamine sulfate was dissolved in 40.9 g of concentrated sulfuric acid under water cooling. 1.35 g (45 mmol) of paraformaldehyde was slowly added to this reaction solution so that the reaction temperature did not exceed 10°C.

This reaction mixture was added dropwise to 500 mN ethanol under water cooling, and the resulting precipitate was filtered. After washing with ethanol, this precipitate was washed with 100mj! Dissolve in pure water and add 6. to this solution.
A cold concentrated aqueous solution of 8 g of zinc chloride was added.

The resulting precipitate was filtered, washed with ethanol, and dissolved in 150111 u of pure water. To this liquid was added a cold concentrated aqueous solution in which 8 g of ammonium hexafluorophosphate was dissolved. The resulting precipitate was collected by filtration, washed with water, and then dried to obtain diazo resin-1.

Production of Aluminum Plate A An aluminum plate with a thickness of 0.24 mm was crushed in a 3% aqueous sodium hydroxide solution and washed with water, and then anodized in a 32% aqueous sulfuric acid solution at a temperature of 30°C and a condition of 5^/dlD2 for 10 seconds. washed with water, crushed in a 2% aqueous sodium metasilicate solution at a temperature of 85°C for 37 seconds, and further boiled at a temperature of 90°C.
of water (pH 8.5) for 25 seconds, washed with water, and dried to obtain aluminum plate a.

A primer layer composition having the following composition was applied to an aluminum plate a, and after drying at 85° C. for 3 minutes, front exposure of 1000 m 47 cm” was performed using a 3 KW ultra-high pressure mercury lamp.

It was further dried at 100° C. for 4 minutes to form a primer layer with a thickness of 15 μm.

(Primer layer composition) Diazo resin - 110g Copolymer of 2-hydroxyethyl methacrylate/methyl methacrylate (501:50 molar ratio) 100g Zinc oxide (white pigment) 20g Get Yellow 402 (yellow pigment) 10g Methyl lactate 800g Next, the above A photosensitive composition having the following composition was applied on the brimer layer, and 100%
It was dried at ℃ for 2 minutes to form a photosensitive layer with a thickness of 0.3 μm.

(Photosensitive composition) (1) Diazo resin - 150 parts (2) 2-hydroxyethyl methacrylate, N(4-
(hydroxyphenyl) methacrylamide and methacrylic acid in a molar ratio of 40157/3 copolymer resin - 150 parts (3) Victoria Pure Blue BOf ((manufactured by Hodogaya Chemical Co., Ltd., dye) 1 part (4) Methyl cellosolve 900 parts then the above The following silicone rubber composition was applied on the photosensitive layer at a dry weight of 1.8 g/m
2 and dried at 90° C. for 10 minutes.

(Silicone rubber layer composition) (1) Dimethylpolysiloxane having hydroxyl groups at both ends (molecular weight 82,000) 100 parts (2) Triacetoxymethylsilane 10 parts (3) Dibutyltin laurate 0.8 part (4) Isopar E (manufactured by Esso Chemical) 900 parts Next, a 5 μm thick polypropylene film was laminated on the silicone rubber layer to obtain a waterless planographic plate.

After a positive film was vacuum-adhered to the upper surface of the above plate material, it was exposed to light using a metal halide lamp as a light source.

Next, after immersing it in the developer-1 below for 1 minute, the surface of the plate material is rubbed with a pad impregnated with the developer.
The silicone rubber layer and photosensitive layer in the unexposed areas are removed, and
A printing plate in which halftone dots of % to 98% were well reproduced was obtained.

Further, the image area of the above printing plate could be vividly dyed by applying a dyeing liquid having the composition shown below to a cloth, lightly rubbing the plate, and then washing with water.

This waterless plate was also mounted on a Heidelberg GTO printing machine with the water supply device removed, and black ink (TOYOKING LILTRA T
100,000 clean prints were obtained when printed with UK Aquares G).

(Developer) β-anilinoethanol 0.5 parts Bepropylene glycol 1.0 parts p-ter
t-Butylbenzoic acid 1.0 part Potassium hydroxide 1.0 part Polyoxyethylene lauryl ether 0.1 part Potassium sulfite
2.0 parts potassium metasilicate
3.0 parts water
91 parts (staining solution) Tulfit (manufactured by Kuraray Sobren Chemical Co., Ltd., solvent) 10 parts Leshidol TW-0120 (manufactured by Kao Corporation, surfactant) 0
．． 5 parts benzyl alcohol 2.5 parts Victoria Pure Blue B OHO, 5 parts water
100 parts Comparative Example-1 A lithographic printing plate material requiring no dampening water was obtained in the same manner as in Example-1, except that the primer layer composition of Example-1 was changed as follows.

(Primer layer composition) Photosensitive unsaturated polyester obtained by 1-part polycondensation of p-fuylene diallylic acid ester and 1,4-dihydroxyethyloxycyclohexane 10 parts by weight 1-methyl-2-benzoylmethylene-β -Naphthothiazoline 0.6 parts by weight KB
M-603 (manufactured by Shin-Etsu Chemical Co., Ltd., silane coupling agent,
N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane) 0.5 parts by weight Methyl cellosolve acetate 150 parts by weight Toluene 150 parts by weight Methyl cellosolve 150 parts by weight After coating this primer layer composition, the composition was heated at 120°C. It was heated and cured for 5 minutes.

Next, the film was developed using the developer described above, and then dyed.

The obtained results were 95% with poor halftone dot reproduction in some shadows.
It showed only reproducibility. Further, when printing was performed in the same manner as in Example 1, stains occurred in the non-image area after 55,000 sheets were printed.

Example 2 A lithographic printing plate material that does not require dampening water was obtained in the same manner as in Example 1, except that the primer layer composition of Example 1 was changed as follows.

(Primer layer composition) Copolymer of 2-hydroxyethyl methacrylate/methyl methacrylate (501:50 molar ratio) 100 parts by weight Pentaerythritol tetraacrylate 100 parts by weight DE
TX (initiator, manufactured by Nippon Kayaku Co., Ltd.) 5 parts by weight EPA
(Sensitizer, manufactured by Nippon Kayaku Co., Ltd.) 5 parts by weight Zinc oxide (manufactured by Sakai Chemical Co., Ltd., white pigment) 30 parts by weight Get Yellow 402 (manufactured by Inu Nippon Ink Co., Ltd., yellow pigment) 10 parts by weight Methyl lactate 1000 parts by weight When developed in the same manner as in Example-1, the silicone rubber layer and photosensitive layer in the unexposed areas were removed, and a printing plate with good dyeability and well-reproduced halftone dots of 2% to 98% was obtained. Ta.

Further, when printing was carried out in the same manner as in Example 1, 120,000 sheets of prints without stains were obtained.

Example 3 A lithographic printing plate material that does not require dampening water was obtained in the same manner as in Example 1, except that the photosensitive composition of Example 1 was changed as follows.

(Photosensitive composition) (1) 50 parts (2-1 ) 4 of glycidyl methacrylate and metaxylene diamine
: 25 parts of adduct of 1 (2-2)
Trimethylolpropane triethoxy triacrylate 10 parts (2-3) Tetramethylolmethane tetraacrylate 5 parts (2-4) Trimethylolpropane triacrylate
10 parts (3) 2,4-diethylthioxanthone 7
Part (4) p-dimethylaminobenzoic acid isoamyl ester Part 3 (5) Victoria Pure Blue BOH0.2 part (6) Methyl cellosolve
When 500 copies were developed in the same manner as in Example 1, the silicone rubber layer and photosensitive layer in the unexposed areas were removed, and a printing plate with good dyeability and well-reproduced halftone dots was obtained.

Further, when printing was carried out in the same manner as in Example 1, 75,000 sheets of prints without stains were obtained.

[Effects of the Invention] In the present invention, since the primer layer contains a photosensitive composition and the thickness of the primer layer is set to 6 μm or more, it is possible to obtain a printing plate with high stiffness resistance, wide development latitude, and halftone dots. Excellent reproducibility.

Claims (1)

[Claims] In a photosensitive lithographic printing plate that does not require dampening water and has a primer layer, a photosensitive layer, and an ink repellent layer in this order on a substrate, the primer layer is (1) a diazo resin, (2) at least two polymers can be polymerized in one molecule. (3) an ethylenically unsaturated compound having an unsaturated group; and (3) a photopolymerization initiator, the primer layer having a thickness of 6 μm or more. Lithographic printing plate.