JPH0279043A - Waterless photosensitive planographic printing plate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to positive and negative dampening water-free photosensitive lithographic printing in which an ink-repelling layer contains a polymer having polyorganosiloxane units in side chains. It concerns the edition.

(Prior Art) A number of photosensitive lithographic printing plates that do not require dampening water and are composed of a substrate, an ink repellent layer provided on the substrate, and a photosensitive layer provided on this layer have been proposed. Regarding a positive type photosensitive lithographic printing plate that does not require dampening water and uses a photosensitive layer containing an orthoquinonediazide compound together with a novolak resin, epoxy resin, acrylic resin, etc., Japanese Patent Publication No. Shojj-IA7313, Japanese Patent Publication Sho &/ -613 Publication, JP-A Shoj Otsu-237≠
It is stated in the Q bulletin. In addition, examples of negative-working photosensitive planographic printing plates that do not require dampening water and whose photosensitive layer is formed from a photopolymerizable composition, and negative-working photosensitive planographic printing plates that do not require dampening water using diazo resin are known. ing. (Tokuko Sho tIL7-23
(See Publication No. 67) (Problems to be Solved by the Invention) However, all of the printing plates disclosed in these documents use silicone having a siloxane bond as the main chain as an ink repellent layer, and there is a problem with silicone. It is difficult to manufacture because photosensitive layers with low affinity must be laminated. For example, in Japanese Patent Publication No. ShojJ'-11L7313,
A polyolefin film coated with a photosensitive layer,
A manufacturing method is shown in which a silicone layer is pressed onto a support. However, it is extremely difficult to manufacture industrially using such a method.

In addition, since photosensitive layers having low affinity with silicone are laminated, there is a problem that the adhesive force at the interface between the two layers is insufficient, making it difficult to obtain a good image.

For these reasons, an ink repellent layer that has strong affinity with the photosensitive layer and sufficient adhesive strength at the interface between the two layers has been desired.

(Means for Solving the Problems) The present inventors have developed an ink repellent layer that has a strong affinity with the photosensitive layer and has sufficient adhesion at the interface between the two layers, and that allows the photosensitive layer to be easily applied. As a result of intensive research on repellent layers, it was discovered that the above object could be achieved by incorporating a graft polymer having polyorganosiloxane units in the side chains (branch polymers) into the ink repellent layer, and the present invention was developed based on this knowledge. reached. That is, the gist of the present invention is a photosensitive lithographic printing plate in which an ink repellent layer and a photosensitive layer are provided in this order on a substrate, wherein the ink repellent layer is made of a polymer having polyorganopolysiloxane units in its side chains. A dampening water-free photosensitive lithographic printing plate characterized by containing:

The present invention will be explained in detail below.

The photosensitive lithographic printing plate that does not require dampening water of the present invention has a specific silicone layer serving as an ink repelling layer and a photosensitive layer serving as an ink receiving layer on a substrate in this order.

The substrate is not particularly limited as long as it has the flexibility to be set in a normal lithographic printing machine and can withstand the load applied during printing. Examples include papers such as coated paper, metal plates such as aluminum plates, and plastic films such as polyethylene terephthalate. It is also useful to provide antiversion layers on these substrates.

The resin used in the ink repellent layer of the present invention has side chains (
It is a graft polymer having a branch unit as shown in the following formula (1) in the branch polymer.

士S□−〇+−・・・・・・・・・・・・(1) Here R1,
R2 is each a hydrogen atom, an unsubstituted or substituted (e.g., halogen atom, cyano group, or amine group) carbon group 1 to 10 methyl groups, alkyl groups, alkenyl groups, or phenyl groups; selected. The molecular weight of the branched polymer is arbitrary, but preferably the number average molecular weight (
GPC method, polystyrene conversion is about ioo to 10,000, particularly preferably j00 to 7, θθθ.

Such graft polymers can be used, for example, in [Kobunshi Ronshu J.
VOL;J, &/ /%p, 7! / (/rB According to the description in o, it can be synthesized by copolymerizing a macromonomer having a polymerizable functional group at the end of a polyorganosiloxane and a monomer copolymerizable with it (macromonomer method). can.

When used in radical polymerization, the terminal polymerizable functional group of the macromonomer of polyorganosiloxane includes, for example, a methacryloyl group, an acryloyl group, a crotonoyl group, an incrotonoyl group, an oleoyl group, and the like. Preferred are methacryloyl group, acryloyl group, and crotonoyl group. In addition, when polymerizing with polyester or polyamide, examples of terminal polymerizable functional groups include hydroxyl group, dihydroxyl group, carboxyl group, and dicarboxyl group.

In the present invention, organopolysiloxane units are combined with side chains (
The copolymerizable component of the main chain (trunk polymer) of the graft polymer contained in the branch polymer is a monomer that can be copolymerized with the above-mentioned macromonomer.

In particular, as monomers for radical polymerization constituting these main chains, the following compounds having unsaturated bonds are used.

(1) Monomers having a hydroxyl group: 2-hydroxyethyl (meth)acrylate (in this specification, expressions such as (meth)acrylate etc.
Acrylate” and “Methacrylate”
Both are used as a generic term. ), (meth)acrylate monomers such as co-hydroxyprobyl (meth)acrylate, l-hydroxypentyl (meth)acrylate, Hiro-hydroxyphenyl (meth)acrylate, 2-hydroxyphenyl (meth)acrylate,
(meth)acrylamide monomers such as N-methylol (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, N-(hydroxyphenyl)-(meth)acrylamide, N-(hydroxynaphthyl)-(meth)acrylamide, o -, m-, p-hydroxystyrene monomers, etc. ((meth)acrylic acid ester or amide monomers other than 21(1): methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meta)
Alkyl (meth)acrylates such as acrylate, N
-Phenyl (meth)acrylamide, o-1m-1p-
Methoxyphenyl (meth)acrylamide, 0-1m-
1p-Ethoxyphenyl (meth)acrylamide, etc. (3) Monomers having a cyan group in the side chain: (meth)acrylonidonitrile, 2-pentenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, 0- lm-', p-cyanostyrene, etc. (4) Monomers 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, phthyl vinyl ether, octyl vinyl ether, phenyl vinyl ether, etc. (6) Styrenes: α-methylstyrene , methylstyrene, chloromethylstyrene, styrene, etc. (vinyl ketones 5: methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, etc. (8) (monomers other than 11 to (7): ethylene, propylene, imbutylene, phtadiene) , olefins such as vinyl chloride, N-vinylpyrrolidone, N-vinylcarbasol, and ≠-vinylpyridine.

Other monomers that can undergo radical copolymerization with these monomers may be used. In the present invention, the above (1)
, (21, (3) and/or (4) are preferred.

Although specific monomers have been listed as constitutional units of the main chain (stem polymer) component, the present invention is not limited to only those listed above.

In the above graft polymer, preferable examples of the structural unit having a polyorganosiloxane unit in the side chain include:
Examples include those represented by the following formula (2).

+CH, -C--← ・・・・・・・・・(2) C=
O ■ Not R5-Si-R'! In the formula, R3, R'lR'l and R7 each represent a hydrogen atom, an alkyl group (methyl group, ethyl group, etc.) or a halogen atom, and R' is a linking group, for example, a cycloalkylene group (cyclohexylene group, etc.) It represents an arylene group (phenylene group, tolylene group, naphthylene group, etc.), an alkylene group (alkylene group having carbon number/~!), and n represents an integer of 2 or more.

Further, preferable structural units constituting the copolymer with the above structural units include those represented by the following formulas (3) and/or (4).

C=OCN In the formula, R8 and R10 each represent a hydrogen atom or an alkyl group (especially preferably a methyl group or an ethyl group),
R9 represents a hydroxy group, an alkoxy group, a hydroxy group, or an alkoxy group. ) is shown.

The proportion of each of these structural units in the copolymer is expressed by the formula (2
) is the constituent unit indicated by! ~70 weight ratio, preferably
5 to 60% by weight of the structural unit represented by formula (3) o −t
o weight%, preferably 10 to 60% by weight, formula (4)
The structural units represented by Q to Rj% by weight, preferably 1
0-♂! Weight percent ranges are preferred.

The graft polymer has a weight average molecular weight of 10,000 to 1,000,000, preferably 1,000,000 to 600,000, as determined by the generally known gel permeation chromatography method.

When this graft polymer having polyorganosiloxane as a branch polymer is used as an ink repellent layer on a substrate, the film thickness is 0.3 μm~/! μm1 preferably ゛, 0.48m
"-' / 0 μm.

In the present invention, both positive type and negative type photosensitive layers are applicable. Examples of orthoquinone diazide compounds that can be used in positive type photosensitive lithographic printing plates that do not require dampening water include polycondensation resins of phenols and aldehydes or ketones and those represented by the following formula (5) or (6). Examples include orthoquinonediazide sulfonic acid esters or carboxylic acid esters obtained by chemically condensing orthoquinonediazide sulfonic acid or carboxylic acid derivatives.

(In the formula, X is a group represented by -8O, Y or -COY, and means a group that can be removed during condensation of Yfd halogen atom, alkali metal, etc.) As a specific example, n,
/, 2-benzoquinone diazide (2)-μm sulfonyl chloride, /, 2-benzoquinone diazide (21-
μ-carbonyl chloride, l,2-benzoquinone diazide (2)-j-sulfonyl chloride, /, J-benzoquinone diazide (21-J-1 carbonyl chloride, etc.).Compounds represented by the above formula (6) As a specific example, /, 2-naphthoquinonediazide (2)-μm
Sulfonyl chloride, /, 2-naphthoquinone diazide (
2) -≠-carbonyl chloride, /, 2-naphthoquinonediazide (2) -j-sulfonyl chloride, /, 2-naphthoquinonediazide (2) -j-carbonyl chloride, and the like.

Examples of polycondensation resins of phenols and aldehydes or ketones include polycondensation metals of pyrogallol and acetone, as described in Japanese Patent Publication No. 3-2-2-03; ! - As described in Publication No. 7t31At, a mixture of pyrogallol and resorcin and a polycondensed metal compound of acetone; Formaldehyde-novolac resin, Hala-substituted phenol formalin resin (e.g. para-cresol formalin resin, para-
T-butylphenol/formalin resin, para-ethylphenol/formalin resin, varapropylphenol/
Formalin resin, para-inglobylphenol formalin resin, para-n-edge/lz phenol-formalin resin, paraoctylphenol formalin resin, etc.) As described in Japanese Patent Publication No. 1982-60≠07, the number of carbon atoms is 3. A mixture of phenols containing a phenol substituted with an alkyl group or a phenol group of ~/2 and a phenol or its methyl substituted product or a mixture thereof at a molar ratio of 1 to 1 and a polycondensate of formaldehyde (for example, the above-mentioned para-substituted phenol and Polycondensates of phenol, vala-cresol, meta-cresol, or ortho-cresol, etc.).

The esterification rate of the orthoquinone diazide group to the hydroxyl group of the polycondensation resin of phenols and aldehydes or ketones is preferably lj to 100 molar ratio, more preferably 20 to 40 molar ratio.

Further, other orthoquinonediazide compounds include orthonaphthoquinonediazide sulfonic acid ester of polyhydroxybenzophenone (for example, /, 2-7toquinonediazide (2)-5-sulfonic acid ester, /, 2-naphthoquinonediazide (2) -Koichi sulfonic acid ester, etc.)
etc.

This polyhydroxybenzophenone is a compound formed by replacing two or more hydrogen atoms of benzophenone with hydroxyl groups, such as dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, pentahydroxybenzophenone, octahydroxybenzophenone, or a derivative thereof (for example, )・Substituted products of a rogene atom, an alkyl group, an aryl group, an aralkyl group, a carboxylic acid group), and the like.

Preferably, trihydroxybenzo7enone or tetrahydroxybenzophenone, more preferably,
2,3,4L-trihydroxybenzophenone, λ,
3. Hiroshi, i-tetrahydroxybenzophenone is listed as a keraler.

The esterification rate for hydroxyl groups is preferably 30 to 100.

As the orthoquinonediazide compound used in the present invention, each of the above compounds may be used alone, or two or more thereof may be used in combination.

Among these orthoquinonediazide compounds listed above, 2,3. (I-trihydroxybenzophenone/
, 2-naphthoquinonediazide (2)-yo-sulfonic acid ester or/, 2-naphthoquinonediazide (2)-
Hiro-sulfonic acid ester, metacresol-based formaldehyde/novolac resin/2-naphthoquinonediazide (21-j-sulfonic acid ester or/, 2-naphthoquinonediazide f2) - Hiro-sulfonic acid ester or a mixture thereof is more preferable.

The proportion of the orthoquinonediazide compound in the photosensitive layer is usually 5 to 60% by weight, preferably 20 to 60% by weight.

Conventionally known diazo compounds can be used as appropriate for negative-working photosensitive lithographic printing plates that do not require dampening water, and are typified by condensates of aromatic diazonium salts and, for example, active carbonyl-containing compounds, especially formaldehyde. Diazo resins are included, among which diazo resins soluble in organic solvents are preferred.

Preferred specific examples of the diazo resin include resins with a molecular weight of about 200 to 10 and θOO represented by the following formula (7).

In the formula, R12, R13 and R14 each represent a hydrogen atom, an alkyl group or an alkoxy group, preferably a hydrogen atom, and B15H1 a hydrogen atom, an alkyl group or a phenyl group, preferably a hydrogen atom.

X in the formula represents a counter anion of the diazo resin, specifically, organic carboxylic acids such as PFe, BF4, decanoic acid, and benzoic acid, organic phosphoric acids such as phenylphosphoric acid, and sulfonic acids such as methanesulfonic acid. It shows.

Y in the formula is N)1. It shows S and O. Furthermore, Z in the formula represents a sulfonic acid group, a sulfonate (Na salt, K
[%] represents a phenyl group or naphthyl group substituted with at least one substituent selected from a sulfine group, a sulfinate (Na salt, K salt, etc.) group, an OH group, and a COOH group. The ratio of m and n is m in molar ratio.
/n=/10~10, preferably l/θ~2
Indicates the range of

The content of diazo resin in the photosensitive layer is preferably /~70
The weight ratio is preferably selected from the range of 3 to zO weight ratio.

As the binder resin used in the photosensitive layer of the present invention, in the case of a positive type, for example, a novolak resin as described in JP-A-63-J'ttjθ, a novolac resin as described in JP-A-63-J'ttjθ;
Examples include acrylic resin as described in Japanese Patent No. 2324L. In the case of a negative type, for example, acrylic resin as described in Japanese Patent Application Laid-Open No. 62-57≠7, polyester resin as described in Japanese Patent Publication No. 7-2061, polyamide, etc. are used. can. Furthermore, in any type, it is also useful to use a graft polymer having polyalkyl acrylate (for example, polyethylene acrylate, polypropyl acrylate, polybutyl acrylate, etc.) as a branch polymer as a binder resin to improve ink receptivity. be.

These binder resins are used in the photosensitive layer in an amount of 30 to 77% by weight, preferably ≠0 to 77% by weight.

Also, the film thickness of the photosensitive layer is 0. /μm~lθμm1 preferably /
It is in the range of μm-rμm.

In addition to the above-mentioned materials, the photosensitive layer of the photosensitive lithographic printing plate that does not require dampening water of the present invention may contain dyes, pigments, coatability improvers, plasticizers, Agents, oil sensitizers, stabilizers, etc. can be added.

It is advantageous that the photosensitive layer of the positive type photosensitive lithographic printing plate that does not require dampening water further contains a known exposure-visible image imparting agent.

Examples of the above dyes include Victoria Pure Blue BOH, Oil Blue #603, and Oil Pink @3/2.
．． Patent pure blue, crystal violet, leuco crystal violet, brilliant green,
Ethyl violet, methyl green, erythrosin B
Representative examples include 1-basisofucsin, malachite green, leucomalachite green, m-cresol purple, cresol red, xylenol blue, rhodamine B1 auramine, ≠-p-diethylaminophenylimino naphthoquinone, cyano-p-diethylaminophenyl acetanilide, etc. Examples include triphenylmethane-based, diphenylmethane-based, oxazine-based, xanthine-based, iminonaphthoquinone-based, azomethine-based, and anthraquinone-based dyes.

The dye is usually contained in the photosensitive layer in an amount of about 0.07 to about 10, preferably about 0.05 to r.
Examples include fluorine-based surfactants (ethyl cellulose, methyl cellulose), and nonionic surfactants (eg, Pluronic L-4≠ (manufactured by Mudenka Co., Ltd.)).

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

An example of an oil-sensitizing agent for improving the oil-sensitivity of the image area is JP-A-Sho! j-! 27 esterified product of styrene-maleic anhydride copolymer with alcohol, etc.0 Furthermore, various sensitizers having hydrophobic groups such as p-#rif
p-t-butylphenol-formalin novolac resin, p-t-butylphenol-formalin novolac resin, p-t-
Modified novolak resins such as butylphenol benzaldehyde resin, rosin-modified novolac resin, and 0-naphthoquinonediazide sulfonic acid ester (OH group 17) varnish f conversion rate of these modified novolak resins from 20 to 70 mol%
) etc. can be added.

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, ≠-methoxy 2-hydroxybenzophenone-5-sulfonic acid, etc.).

The amount of these additives added varies depending on the intended purpose, but is generally 0.07% to 30% by weight based on the total solid content.
Weight percent is preferred.

The photosensitive layer of the positive type photosensitive lithographic printing plate that does not require dampening water may further contain a known exposure-visible image imparting agent.
The exposure visible image imparting agent is a compound that generates an acid upon exposure to form a salt with a dye.

As a compound that generates an acid upon exposure to light, a trihaloalkyl compound represented by the following formula is preferable.

(However, Xa is a torino-roalkyl group having carbon atoms/~3, W is N or P, and Z is 0, S or S
e, and Y is a group that cyclizes W and Z and has a chromophore. )Specifically, as a compound, OCR.

Oxadiazole compounds having a benzofuran ring such as
λ- described in Japanese Unexamined Patent Publication No. 1977-7u72r
Trichloromethyl-3-(p-methoxystyryl)-/
, 3. Examples include μm oxadiazole compounds.

Furthermore, ≠-(2,Hiro-dimethoxy-≠-styryl)-4-toIJ chloromethyl-corpyron compound, λ, ≠-bis-
(trichloromethyl)-6-p-methoxysteryl-8
-triazine compound, 2. Examples include Hiro-bis-(trichloromethyl)-6-p-dimethylaminostyryl-S-triazine compound.

The amount of the exposure visible image imparting agent added is 0.0/~20 in the photosensitive layer.
It is preferably a weight factor, more preferably 0. /~1
0 weight person.

The method for producing a photosensitive lithographic printing plate that does not require dampening water according to the present invention will be explained below.

Introduction: Coat the ink repellent layer on the substrate.

Coating solvents include cellosolves such as methylcellosolve, methylcellosolve acetate, ethylcellosolve, and ethylcellosolve acetate, carpitols such as methylcarpitol and ethylcarpitol, dimethylformamide, dimethylsulfoxide, dioxane, acetone,
Examples include methyl ethyl ketone, cyclohexanone, trichloroethylene and the like. As the coating method, conventionally known methods such as spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating, and curtain coating can be used.

Next, a photosensitive layer is applied onto the ink repellent layer. The photosensitive layer is coated by dissolving each of the above-mentioned components in a solvent. Examples of solvents that can be used include cellosolves such as methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve, and ethyl cellosolve acetate, methyl calpitol, Examples include carpitols such as ethyl carpitol, dimethylformamide, dimethyl sulfoxide, dioxane, acetone, methyl ethyl ketone, cyclohexanone, and trichloroethylene.

These solvents may be used alone or in combination of two or more. However, use a solvent that does not dissolve the ink repellent layer as much as possible. The ink repellent layer can be coated by conventionally known methods such as spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating and curtain coating. After coating, the coating film is sufficiently dried to obtain a photosensitive lithographic printing plate that does not require dampening water of the present invention.

Conventional methods can be applied to plate-making the photosensitive lithographic printing plate that does not require dampening water of the present invention obtained as described above. That is, a relief image is obtained by exposing the transparent original image having a line image, halftone image, etc. to light, and then developing it with an aqueous developer. A suitable light source for exposure is tr.

Any general-purpose light source including ultraviolet rays and visible light of nm or more may be used, but carbon arc lamps, mercury lamps, xenon lamps, metal halide lamps, strobes, etc. are particularly preferred.

The developer used in the development process of the dampening water-free photosensitive lithographic printing plate of the present invention may be any known developer, but in particular, in the positive type dampening water-free photosensitive lithographic printing plate, novolac resin is used as a binder resin. In such cases, it is possible to develop using an alkaline aqueous solution (described later) that does not contain an organic solvent. In other cases, it is preferable to use a specific organic solvent together with the alkaline aqueous solution in Mixing 1~. The specific organic solvent herein refers to an organic solvent that can dissolve or swell the non-image area of the photosensitive layer mentioned above when contained in the developer, and that has a solubility in water of 10 below the weight plate at room temperature. means. Such organic solvents only need to have the above-mentioned characteristics. Specifically, for example, carboxylic acid esters such as ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benzyl acetate, ethylene glycol motubutyl acetate, butyl lactate, butyl levulinate, ethyl butyl ketone, methylinobutyl ketone, and cyclohexanone. Ketones such as ethylene glycol motubutyl ether, ethylene glycol monobenzyl ether, ethylene glycol monophenyl ether, alcohols such as benzyl alcohol, methylphenylcarhinol, n-amyl alcohol, methyl amyl alcohol, alkyls such as xylene These include substituted aromatic hydrocarbons, methylene dichloride, halogenated hydrocarbons such as monochlorobenzene, etc. One or more of these organic solvents may be used. Ethylene glycol monophenyl ether and benzyl alcohol are particularly effective.

In addition, the content of these organic solvents in the developer is as follows:
Approximately /~20 weight ratio, particularly preferably Ir! 2
~70 weight class.

Certain solubilizers may also be included to aid in the solubility of these organic solvents in water. Such solubilizers include those that are more water soluble than the above-mentioned organic solvents,
It is better to use low molecular weight alcohols and ketones. Furthermore, anionic activators, amphoteric activators, etc. can also be used. Examples of such alcohols and ketones include methanol, ethanol, propatool, acetone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methoxybutanol, ethoxybutanol, Hiroshi-methoxy-methylbutanol, N- It is preferable to use methylpyrrolidone or the like. Preferred examples of the activator include sodium inpropylnaphthalene sulfonate, sodium n-butylnaphthalene sulfonate, sodium N-methyl-N-pentadecylaminoacetate, and sodium lauryl sulfate. The content of these solubilizers is preferably 30 weight leeward.

On the other hand, the alkaline agents contained in the developer include sodium silicate, potassium silicate, potassium hydroxide, sodium hydroxide, lithium hydroxide, sodium or ammonium salts of dibasic or tertiary phosphoric acid, and metasilicic acid. Inorganic alkaline agents such as sodium, ammonia, mono-, di- or trimethylamine, mono-, di- or triethylamine, mono- or di-impropylamine,
Examples include organic compounds such as n-butylamine, mono-, di- or triethanolamine, mono-, di- or tri-impropanolamine, ethyleneimine; ethylenediamine.

Preferred are organic amine compounds such as sodium silicate, potassium silicate, and organic silicate. Particularly preferred are potassium silicate and di- or triethanolamine.

The content of these alkaline agents in the developer is usually 0.
．． 0! ~♂weight ratio, preferably o3~6 weight ratio.

Further, in order to improve storage stability and the like, it is preferable to include a water-soluble sulfite in the developer as necessary. Such water-soluble sulfites include alkali sulfite IJ
or alkaline earth metal salts are preferred, such as sodium sulfite, potassium sulfite, lithium sulfite, magnesium sulfite, and the like. The content of these sulfites in the developer is usually 0.05 to 1% by weight, preferably 0.7 to 1% by weight.

After imagewise exposure, the photosensitive lithographic printing plate of the present invention that does not require dampening water can be brought into contact with the above-mentioned developer or rubbed, after 70 to 60 seconds at about 10°C to ≠0°C. , the photosensitive layer in the non-image area is completely removed without adversely affecting the image area of the photosensitive layer. A lithographic printing plate is thus obtained.

(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 Example 1 (Synthesis example of polyorganosiloxane macromonomer) α,ω-dihydroxydimethylpolysiloxane 2209 (0.1 mol) and CH represented by the following formula.

HC) fsiohrH(n-meanto)CH.

Pyridine 5', 4' P? (0.72 mol) dissolved in 00 ml of diethyl ether, 77/2.0 &
? A 70% diethyl ether solution (0.0 j mol) was gradually added dropwise at room temperature over 1 hour. The reaction proceeded immediately and white crystals of pyridine hydrochloride precipitated. After the dropwise addition was completed, the mixture was further stirred at room temperature for 1 hour, and the crystals of pyridine hydrochloride were removed by 8 filtration. Next, this liquid was placed in a separatory funnel, water was added thereto, and the mixture was thoroughly shaken and washed with water. After washing with water, the separatory funnel was left standing to separate the upper ether layer and the lower aqueous layer. Anhydrous sulfur was added to the obtained ether layer, and the mixture was left overnight at room temperature to dehydrate.

Thereafter, the anhydrous sulfate is removed by filtration, and the obtained dimethylpolysiloxane macromonomer 22s? has a methacryloyl group as a polymerizable functional group at the terminal and has a number average molecular weight of about r, ooo. I got it.

Synthesis example! (Synthesis Example of Graft Polymer for Ink Repellent Layer) Under a nitrogen stream, each component shown in Table 1 and azobisisobutyronitrile (AIBN)/, j molar ratios were mixed with i and s of the total weight of methyl ethyl ketone. This mixed solution was heated for 60 minutes while stirring. After this reaction, the coating solvent 4t-dioxane was added and the solvent was replaced by vacuum distillation. The mixture was refluxed for 1 hour at 0° C. Afterwards, the solid content was adjusted to 20%.

Table 1 In the table, AN is acrylonitrile, MA is methyl acrylate, PhMA is N-phenylmethacrylamide, M-
/ indicates the dimethylpolysiloxane macromonomer obtained in Synthesis Example 1.

The amount of each component used was expressed in "wt%".

Reference example! (Photosensitive liquid) Arrow l: Birogallol-acetone polycondensation 'h/, 2-naphthoquinonediazide-y-sulfonic acid ester (esterification rate 30%, M W == /, rioo') (b) Negative type Photosensitive liquid-pf2: Hexafluorophosphate of a polycondensate of p-diazodiphenylamine and paraformaldehyde. This diazo resin has a weight average molecular weight of 21rO00 as a polycondensation reaction product with β-naphthol. Table 2 In the table, AN is acrylonitrile, MA is methyl acrylate, and EAi! : Ethyl acrylate, MAA is methacrylic acid, PhMA is N-phenylmethacrylamide, M-2 is polypteracrylate macromonomer (A
B-manufactured by Otsujibaku Agosei Co., Ltd.).

The amount of each component used was expressed in "wt%".

Examples/-/j and Comparative Examples/-j (a) Evaluation of coating properties (Example) The graft polymer for the ink repellent layer shown in Table 1 was mixed with 100 parts of the graft polymer for the ink repellent layer based on the solid content of the polymer. It was dissolved in dioxane and coated onto a 0.3 tone aluminum plate using a spin coating machine at 0°C and /60 rpm. after that?
! It was dried at ℃ for 3 minutes to create a μμ ink repellent layer.

Next, the photosensitive liquid shown in Reference Example 1 was coated on the ink repellent layer using a spin coater at 1' (, to C, /! Orpm).
It was coated with.

After coating, the state of coating of the photosensitive layer on the ink repellent layer was evaluated. The results are shown in Table 3.

(Comparative example) 5H-2240 primer manufactured by Toray Silicone ■ was applied on an aluminum plate with a thickness of 0.31 at room temperature at / 00 rpm using a spin coater, and the aluminum was coated by air drying at room temperature for 5 minutes. A primer layer was provided on the board.

On this primer layer, a silicone rubber liquid having the following composition was applied using a spin coater at room temperature and 1100 rpm.
After air drying for 1 minute, it was dried at 60° C. for 12 minutes. Thereafter, the silicone rubber was left to cure sufficiently to form an ink repellent layer of //μ. Composition of silicone rubber liquid (a) Dimethylpolysiloxane with hydroxyl groups at both ends (viscosity/3000 Stokes) 100 parts (b)
Methyl tris(methyl ethyl ketoxime) silane 70 parts (C) Dibutyltin diacetate 0.2 parts (d) Methylcyclohexane 70 parts (C)
jIQO section Next, the photosensitive liquid shown in Reference Example 1 was applied onto the ink repellent layer using a spin coating machine at 10°C, l! orp
It was coated so that the film thickness was 3 μm.

After coating, the state of coating of the photosensitive layer on the ink repellent layer was evaluated. The results are shown in Table 3.

Table 3 (Continued from Table 3) In the table, "uncoatable" means that the photosensitive layer could not be coated on the ink repellent layer at all. Also, "coatable" means that the photosensitive layer was coated evenly and uniformly over the entire surface of the ink repellent layer.

(bJ Printing Evaluation) In Examples /-/j of (a) above, the respective photosensitive liquids were applied and then dried at ?!C for 3 minutes to produce photosensitive lithographic printing plates that did not require dampening water.

The obtained photosensitive lithographic printing plate that does not require dampening water is exposed to light from a distance of 700 cm using a 3KW ultra-high pressure mercury lamp, developed, and the actual printing is performed to improve ink receptivity in image areas and ink repulsion in non-image areas. The gender was evaluated.

The developing solution used was the following developer solution-7 except for the one using binder N-/(novolak resin). In the case of a positive type, the development method was carried out by immersing the following developer -/ in a solution diluted 12 times with water at 26"C for 2Q seconds, and then washing with water. In the case of a negative type, the following developer -7 was used. The sample was diluted with water to 1:1 and immersed at 2J°C for ≠θ seconds, and then washed with water.

Those using binder N-/(novolac resin) are 5D.
R-/ (manufactured by Konica ■) A developing solution diluted 6 times with water was immersed at 25° C. for ≠Q seconds and then washed with water for development.

(Composition of developer-7) Benzyl alcohol soy triethanolamine lj? sodium sulfite
Yo? Sodium butylnaphthalene sulfonate 2 nights? water
jθθ 2 printing is Sun Offset 22
Testing was carried out using 0E (manufactured by San Printing Machinery ■) without supplying dampening water. The ink used was Toyo King Tart 9TKU Aquares G ink (manufactured by Toyo Ink Manufacturing ■). Table ≠ shows the results of evaluating the ink receptivity of the image area and the ink repulsion of the non-image area on the printed matter. The quality of the ink repulsion in the non-image area was judged based on whether the printed matter had scumming or not. In addition, the ink receptivity of the image area was indicated by the number of sheets of waste paper.

Table μ (Effects of the present invention) As explained in detail above, if the graft polymer having the polyorganosiloxane of the present invention as a branch polymer is used in the ink repellent layer, it is extremely easy to manufacture and has excellent coating properties. A remarkable effect is obtained in that a photosensitive lithographic printing plate that does not require water is obtained. Therefore, the present invention is extremely useful industrially.

Claims (1)

[Claims] (1) A photosensitive lithographic printing plate in which an ink repellent layer and a photosensitive layer are provided in this order on a substrate, and the ink repellent layer contains a polymer having polyorganosiloxane units in side chains. Features a photosensitive lithographic printing plate that does not require dampening water.