JPH03274556A - Dampening waterless photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To improve flawing resistance, dyeability and adhesiveness by incorporating at least a hydroxyl group-contg. polymer and a diazo resin into a photosensitive layer and forming a silicone rubber layer of a silicone rubber compsn. contg. at least organo-polysiloxane and a reactive silane compd. having an isocyanurate group. CONSTITUTION:The photosensitive layer has at least the hydroxyl group-contg. polymer and the diazo resin and the silicone rubber is formed of the silicone rubber compsn. contg. at least the organo-polysiloxane and the reactive silane compd. having the isocyanurate group. A diazo resin, etc., obtd. by bringing a diazo compd. and a diproxyl group-contg. poly(meth)acrylic acid is preferably used as the hydroxyl group-contg. polymer. Linear organo-polysiloxane or the organo-polysiloxane crosslinked to some extent is preferably as the organo- polysiloxane. The improvement in the flawing resistance, the dyeability and the adhesiveness is made in this way.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a photosensitive planographic printing plate that does not require dampening water, and more specifically, a primer layer, a photosensitive layer, and a silicone rubber layer are formed on a substrate in this order This invention relates to a photosensitive lithographic printing plate that does not require dampening water and is coated.

[Prior art] Conventionally, in lithographic printing, it was necessary to perform printing by making use of the lipophilicity of the image area and the hydrophilicity of the non-image area, and by maintaining a delicate balance between water and ink, which required considerable skill. Needed.

In other words, in the conventional printing method that requires dampening water, an image-like lipophilic portion is formed by passing an image film through a plate material coated with a lipophilic photosensitive layer on a hydrophilic support, and then developing it. A printing plate is prepared by providing a parent wood portion which is a non-printing portion. During printing, water is first transferred to the non-image areas, and then ink is transferred. The ink does not adhere to the non-print areas where water is present, but only to the print areas. However, this method
It is difficult to control the delicate balance between the dampening water and the ink, which can cause emulsification of the ink, or the ink may mix with the dampening water, causing poor ink density and background smearing, which can cause major problems such as side paper. had.

Furthermore, the transfer of dampening water to the printing material causes a change in the dimensions of the printing material, which has the disadvantage that the sharpness of the image is impaired, especially when printing in multiple colors.

For this reason, attempts have been made to develop lithographic printing plates that do not require dampening water (hereinafter referred to as "waterless lithographic plates"). A waterless lithographic plate having a structure in which a silicone layer is provided on a photosensitive layer on a body is disclosed, and a plate making method is further disclosed in which the photosensitive layer is dissolved in a developer and the upper tricone rubber layer is removed to form an image area. Disclosed. Also,
Special Publication No. 54-25923 and No. 56-23150
The patent publication has a structure similar to the above in that a silicone rubber layer is provided on a photosensitive layer on a support, but the photosensitive layer does not dissolve in a developer and the photosensitive layer and silicone rubber layer are separated by image exposure. A method is disclosed in which the silicone rubber layer is selectively swelled and removed by photoadhesion or by irradiating light 1.

Furthermore, Japanese Patent Publication No. 61-54219, Japanese Patent Publication No. 60-22
No. 9031 and No. 62-494255 disclose waterless planographic plates having a structure in which a photosensitive layer and a silicone layer are provided on a primer layer on a support.

[Problem to be solved by the invention] The above-mentioned Japanese Patent Publications No. 44-23042 and No. 46-160
The method disclosed in Publication No. 44 can increase the adhesive strength between the silicone rubber layer and the photosensitive layer, and between the support and the photosensitive layer, and can be expected to produce a plate with excellent image quality, stiffness resistance, and scratch strength. There were disadvantages in that the lines had to be relatively deep recesses, and in order for the ink to be sufficiently deposited, it had to be thick.

Also, Japanese Patent Publication No. 54-26923 and No. 56-23
The method described in Publication No. 150 can avoid the above-mentioned drawbacks of ink build-up, but since it utilizes the delicate adhesion between the silicone rubber layer and the photosensitive layer, it is difficult to design the silicone layer, resulting in poor scratch strength and image reproducibility. There were some difficulties.

Furthermore, although the method disclosed in JP-A No. 60-229031 improves the above-mentioned drawbacks, it has the disadvantages of poor dyeability of the primer layer and insufficient adhesion between the photosensitive layer and the primer layer. Also, special public service Sho 61-542
In the methods described in Japanese Patent No. 19 and JP-A-62-194255, the primer layer is mainly thermally crosslinkable and cured by heating after being coated on the support, resulting in poor production efficiency and poor economics. It had the disadvantage of being disadvantageous.

In Japanese Patent Application No. 1-104286, the present inventors improved the above-mentioned drawbacks by containing at least (11) diazo resin and (2) hydroxyl group-containing polymer in the photosensitive layer. et al., as a result of intensive studies to provide a water-free photosensitive lithographic printing plate with such a structure and even higher scratch resistance, found that the photosensitive layer contains at least a water #, I-containing polymer and a diazo resin, and a silicone rubber. The present inventors have discovered that scratch resistance can be improved by forming the layer from a silicone rubber composition containing at least an organopolysiloxane and a reactive silane compound having an isocyanurate group.

That is, the object of the present invention is to improve the scratch resistance and to maintain the properties such as dyeability and adhesion without deteriorating. M l,
An object of the present invention is to obtain a water-free photosensitive lithographic printing plate, which comprises on a substrate at least a primer layer, a photosensitive layer, and a silicone rubber layer in this order from the substrate side;
The photosensitive layer contains at least a hydroxyl group-containing polymer and a diazo resin, and the silicone rubber layer is formed from a silicone rubber composition containing at least an organopolysiloxane and a reactive silane compound having an isocyanurate group. This is achieved using a photosensitive lithographic printing plate that does not require dampening water.

The present invention will be explained in more detail below.

The photosensitive layer used in the present invention contains a diazo resin and a hydroxyl group-containing polymer as essential components.

As the diazo resin, for example, Photo Ink Science and Engineering (Photo
, Sci, Eng,) Volume 17, Page 33 (I973)
, U.S. Patent No. 2,063°631, U.S. Patent No. 2.679,
A diazo compound and an active carbonyl compound (for example, formaldehyde, acetaldehyde or penzaldehyde, etc.) whose production methods are described in the specifications of No. 498, No. 3050.502, and JP-A-59-78340, etc. A diazo resin obtained by condensing in an acidic medium such as sulfuric acid, phosphoric acid, or hydrochloric acid, a method for producing the diazo compound is described in Japanese Patent Publication No. 49-4001, and a diphenyl ether derivative is condensed with the diazo compound. A diazo resin etc. obtained by the reaction can be used. Particularly preferred is a condensate of paradiazodiphenylamine and formalin.

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

These include organic carboxylic acids such as decanoic acid and benzoic acid;
Contains organic phosphoric acids and sulfonic acids such as phenyl phosphoric acid,
Typical examples include methanesulfonic acid, chloroethanesulfonic acid, dodecanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, mesitylenesulfonic acid and anthraquinonesulfonic acid, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, hydroquinone Sulfonic acid, 4-acetylbenzenesulfonic acid, dimethyl-5
= Aliphatic and aromatic sulfonic acids such as sulfoisophthalate, 2.2', 4.4'-tetrahydroxybenzophenone, 1.2.3-)lihydroxybenzophenone,
2. Hydroxyl group-containing aromatic compounds such as 2', 4-trihydroxybenzophenone, halogenated Lewis acids such as hexafluorophosphoric acid and tetrafluoroboric acid, Cl 04 ,
Halogenated Lewis acids such as perhalogen acids such as I 2 Oa are preferred, and hexafluorophosphoric acid is particularly preferred. The molecular weight of the diazo resin is determined by gel permeation chromatography (GPC) of the coupled product with β-naphthol.
) has a weight average molecular weight of 200 to 10,000.
(Styrene equivalent) is preferably in the range of 500 to 5000
The range is more preferable.

In the present invention, the proportion of the diazo resin in the photosensitive layer is usually 1 to 90% by weight, preferably 3 to 60% by weight.

Further, as the hydroxyl group-containing polymer in the present invention, an alcoholic hydroxyl group-containing poly(meth)acrylic acid ester or amide is preferably used.

Examples of the monomer having an alcoholic hydroxyl group include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, N-(4-hydroxyethylphenyl)methacrylamide, and hydroxy-methyldiacetone (meth)acrylamide. Particularly preferred are 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate.

The monomer copolymerizable with the above hydroxyl group-containing monomer includes (1) a monomer having an aromatic water M group, such as N-(4
-hydroxyphenyl)acrylamide, N-(4-hydroxyphenyl)methacrylamide, o-, m-,
p-hydroxystyrene, 0-m-, p-hydroxyphenyl-acrylate or -methacrylate, (2) α, β-unsaturated carboxylic acids such as acrylic acid, tamacrylic acid, maleic anhydride, (3) methyl acrylate, Ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, acrylic acid-
(Substituted) alkyl acrylates such as 2-chloroethyl, 2-hydroxyethyl acrylate, glycidyl acrylate, N-dimethylaminoethyl acrylate, (4) methyl methacrylate, ethyl methacrylate,
Propyl methacrylate, butyl methacrylate, amyl methacrylate, cyclohexyl methacrylate, 2
-Hydroxyethyl methacrylate, 4-hydroxybutyl methacrylate, glycidyl methacrylate, N-
(Substituted) alkyl methacrylates such as dimethylamine ethyl methacrylate, (5) acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N-ethyl acrylamide, N-hexyl methacrylamide, N-cyclohexyl acrylamide, N-hydroxyethyl Acrylamide, N-phenylacrylamide, N-nitrophenylacrylamide, N-ethyl-
Acrylamides or methacrylamides such as N-phenylacrylamide, (6) vinyl ethers such as ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether, phenyl vinyl ether, (7) vinyl acetate, Vinyl esters such as vinyl chloroacetate, vinyl butyrate, vinyl benzoate, (8) Styrenes such as styrene, α-methylstyrene, methylstyrene, chloromethylstyrene, (9) Methyl vinyl ketone, ethyl vinyl ketone, propyl Vinyl ketones such as vinyl ketone and phenyl vinyl ketone; (lO) olefins such as ethylenebucopyrene, isobutylene, butadiene, and isoprene; (11) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, acrylonitrile, methacryl Examples include nitrile, etc. Among these, particularly preferred are 1) to (4).
).

The amount of hydroxyl group-containing monomer in the hydroxyl group-containing polymer is not particularly limited, but is preferably 5 to 100% by weight.
, particularly preferably from 20 to 100% by weight.

The weight average molecular weight of the hydroxyl group-containing polymer of the present invention measured by GPC method is preferably 5,000 to 1,000,000 (in terms of styrene). If the value is lower than 5,000, it may be attacked by the coating solvent or developer of the photosensitive layer even after photocuring, and 1
If the value is larger than 000000, it is difficult to select a coating solvent.

The proportion of the hydroxyl group-containing polymer in the photosensitive layer is usually 10 to 99% by weight, preferably 40 to 97% by weight.

The weight ratio of diazo resin and hydroxyl base to polymer is l/9.
The range of 9 to 90/10 is preferable.

If the diazo resin is less than 1/99, it may not be sufficiently crosslinked even after photocuring and may be damaged by the coating solvent or developer. On the other hand, if the diazo resin is more than 90/10, the polymer ratio will inevitably be lowered. becomes smaller and the hydroxyl group content becomes lower, so the adhesion with the silicone layer tends to decrease.

Furthermore, the photosensitive layer of the present invention may also contain a photoinsolubilizable photosensitive substance such as a compound having an addition polymerizable vinyl group.

Examples of compounds having an addition polymerizable vinyl group include compounds having a boiling point of 100°C or higher under normal pressure and having two or more polymerizable terminal ethylene groups, such as unsaturated carboxylic acids, unsaturated carboxylic acids, and aliphatic polyhydroxy esters with compounds, esters between unsaturated carboxylic acids and aromatic polyhydroxy compounds, esters between unsaturated carboxylic acids and polyhydric carboxylic acids, and polyhydric hydroxy compounds such as the aforementioned aliphatic polyhydroxy compounds and aromatic polyhydroxy compounds. Examples include esters obtained by esterification reactions, which are specifically described in JP-A-59-71048.

In addition to the above-mentioned materials, the photosensitive layer of the present invention may also contain dyes, pigments, or exposure-visible agents, if necessary.
By adding a coating property improver or the like, it is possible to improve the developed visible image properties, the exposed visible image properties, and the coating properties.

As the above dye, for example, Victoria Pure Blue B
OH, oil blue #6o3, oil pink #312,
Patent pure blue, crystal violet, leuco crystal violet, brilliant green, ethyl violet, methyl green, erythrosin B1
Toxins such as basil, malachite green, leucomalachite green, m-cresol purple, cresol red, xylenol blue, rhodamine B, auramine, 4-p-diethylaminophenylimino naphthoquinone, cyano-p-diethylaminophenyl acetanilide, etc. Examples include phenylmethane-based, diphenylmethane-based, oxazine-based, xanthine-based, iminonaphthoquinone-based, azomethine-based, and anthraquinone-based dyes.

The above dye is usually about 0.01 to about 10% by weight in the photosensitive layer.
, preferably about 0.05 to 8% by weight.

As the coating property improver, alkyl ethers, (4M,
t-ethylcellulose, methylcellulose), fluorine-based surfactants, nonionic surfactants (e.g. "Pluronic L-64" (manufactured by Asahi Denka), "FC-430"
(manufactured by 3M)).

In addition, as the exposed visible image agent, for example, JP-A-54-74
Examples thereof include oxadiazole compounds described in JP-A No. 728 and triazine compounds described in JP-A-53-36223.

In the present invention, the film thickness of the photosensitive layer is 0.1■/dm2 to 3
0■/dm2 is preferable, 0.5 w/d+z~10
tz/ds" is more preferable.

The silicone rubber layer used in the present invention contains as essential components an organopolysiloxane and a reactive silane compound having an isocyanurate group.

The reactive silane compound having an isocyanurate group used in the present invention is represented by the following formula.

1 o, /N"z, p"C, the case where X=OMe is preferable, especially when R2R3=R
It is more preferable that R = -CH2CH2CH2S i (OMe): +.

The amount of the reactive silane compound added is 0.5 to 10%, preferably 1 to 5%, based on the alkaline polysiloxane.

If the amount added is more than 10%, it will adversely affect the ink repulsion.
When it is 0.5% or less, the improvement in scratch resistance is small.

The organopolysiloxane used in the present invention is preferably a linear or somewhat crosslinked organopolysiloxane. The organopolysiloxane usually has a molecular weight of 100,000 to several hundred thousand, and is suitably crosslinked in the form of a liquid, wax, or cake at room temperature. The organopolysiloxanes are 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 by the reaction. Particularly useful condensation-type silicone rubbers include a mixture of a linear organopolysiloxane having hydroxyl groups at both ends or a part of the main chain and a silicone crosslinking agent, or one in which the hydroxyl groups are reacted with a silicone crosslinking agent. In either case, adding a condensation catalyst is advantageous in terms of crosslinking speed.

The organopolysiloxane has the following repeating units in its main chain.

1,5i-0← 2 In the formula, R and R2 are alkyl, aryol, alkenyl, or a combination thereof, each of which may have a substituent such as a cyano group, a halogen atom, a hydroxyl group, and a methyl group, phenyl A vinyl group and a trifluoropropyl group are preferable, and a methyl group is particularly preferable.

The silicone bridge 41Jl is preferably a reactive silane compound having isocyanurate 5 alone, but may be mixed with a known crosslinking agent.

Known crosslinking agents include the so-called acetic acid-removal type, oxime-removal type, alcohol-elimination type, deamination type, dehydration type, and those having a functional group represented by -0H (in the formula, R and R' are alkyl groups). Examples include condensed silicone crosslinking agents such as molds. Examples of such crosslinkers include tetraacetoxysilane, methyltriacetoxysilane, ethylketoacetoxysilane, phenyltriacetoxysilane, dimethyldiacetoxysilane,
Diethyldiacetoxysilane, vinyltriacetoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, vinyltrimethoxysilane 1. Methyl tris (
Examples include methyltri(N-methyl, N-acetylamino)silane, methyltri(methylethylketoxime)silane, methyltri(methylethylketoxime)silane, and oligomers thereof.

All of these crosslinking agents are organopolysiloxane 10
The amount is preferably in the range of 0.5 to 30 parts by weight relative to 0 parts by weight.

Examples of the condensation catalyst include organic carboxylic acids, titanate esters, naphthenic acids, and the like.

The addition type refers to unsaturated groups in the main body, such as vinyl groups (CH
=CH2) is crosslinked by the addition of hydrogen in the crosslinking agent.

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

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

In the silicone rubber layer of the present invention, a condensation type is mainly used, but an addition type may be mixed.

It is also possible to use condensed and addition type organopolysiloxanes having hydroxyl groups, unsaturated groups, etc. in one organopolysiloxane.

Among the commercial products available as the silicone rubber according to the present invention, a preferable example is "KS-705F" manufactured by Shin-Etsu.
KE-41”, “KE-42”, KE-44”, Toshiba Silicone (manufactured) “YE5505”, “YF3057”,
Toshi Silicone (manufactured) “5H-781”, “PRX-3”
Condensation type silicone rubber such as 05""5H-237" and Shin-Etsu (l*I!"KS-837", "KE-103")
Examples include addition-type silicone rubbers such as "KE-106", "KE-1300", "TSE-3032"RTUB" manufactured by Toshiba Silicone Co., Ltd., and "5H-9!555'' manufactured by Toshi Silicone Co., Ltd.

Furthermore, for the purpose of improving the strength of silicone rubber, inorganic fillers such as silica, titanium oxide, and aluminum oxide may be added, and silica is particularly preferably used.

From the viewpoint of dispersibility or dispersion stability, it is preferable for such fillers to have an average particle diameter of 500 μm or less.

In the present invention, the thickness of the silicone rubber layer is preferably as thin as possible from the viewpoint of image quality and developability, but conversely a certain thickness is required from the viewpoint of rigidity resistance, printing stains, etc. dm” to 50■/dm” is preferable, and 5*/d
m" to 30 days/da+" is more preferable.

Surprisingly in the present invention, the above-mentioned characteristics of the silicone rubber layer are particularly effective when at least a hydroxyl group-containing polymer and a diazo resin are used in the photosensitive layer.
Although the detailed mechanism is unknown, it can be assumed that the affinity of the silane compound of the present invention with the isocyanurate group and the presence of a large number of reactive silane compounds in one molecule are involved.

In the present invention, a primer layer is provided between the photosensitive layer and the substrate.

As the primer layer, any of a variety of known primer layers can be applied, but for example, the primer layer described in Japanese Patent Publication No. 61-54219, such as one made by heating and curing epoxy resin, polyurethane resin, etc. using an appropriate hardening side. Alternatively, the primer layer described in JP-A No. 60-229031, which is obtained by photo-curing a layer made of a photodimer-type curable resin, etc., can be used. Furthermore, a primer layer obtained by photocuring a layer mainly composed of a diazo resin and a hydroxyl group-containing polymer is also preferably used. Such a diazo resin is the same as the diazo resin contained in the photosensitive layer, and is usually 1 to 90% by weight, preferably 3% by weight, in the brimer layer.
Contains ~60% by weight.

As the hydroxyl group-containing polymer, the same hydroxyl group-containing polymers contained in the photosensitive layer, polyvinyl alcohol derivatives, epoxy resins, novolac resins, gelatin, cellulose, etc. are used. Such hydroxyl group-containing polymers are contained in the primer layer in an amount ranging from 10 to 99% by weight, preferably from 40 to 97% by weight.

In the present invention, in addition to the above-mentioned essential components, the primer layer includes fillers such as titanium oxide and zinc oxide, or antihalation agents, coloring agents such as dyes and pigments, coating properties improving agents, plasticizers, and stabilizers. , an oil-sensitizing agent, etc., in an amount not exceeding 50% by weight.

As the dye and the coatability improving side, the same dyes as those contained in the photosensitive layer are used.

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, tetrahydrafurfuryl oleate, oligomers of acrylic acid or methacrylic acid, etc. .

In addition, in order to improve the printing ink adhesion of images, various additives having hydrophobic groups, such as p-octylphenol formalin novolac resin, p-t-butylphenol formalin novolak resin, p-t-butylphenol henzaldehyde, etc. Resins, modified novolak resins such as rosin-modified novolak resins, and 0-naphthoquinonediazide sulfonic acid esters (esterification rate of OHi of 20 to 70 mol %) of these modified novolak resins can be added.

The above-mentioned photocurable diazo resin or a composition containing the same and a hydroxyl group-containing polymer are dissolved in an appropriate organic solvent together with other additives added as necessary, and then applied onto a support and dried. After that, it is exposed to light to completely decompose the diazo resin and harden it, thereby forming a primer layer.

The thickness of the primer layer is 1■/d1112~200■/d
m”, more preferably 3■/dI
It is 112 to 100 .mu./di2.

Further, in the waterless planographic plate of the present invention, a protective layer may be provided on the silicone rubber layer, and methods for providing the protective layer include the method of laminating a polypropylene film etc. described in Japanese Patent Publication No. 61-614, or the method of laminating a polypropylene film etc. described in Japanese Patent Publication No. 61-614. A method of coating a high molecular weight polymer described in Japanese Patent No. 27545 is known.

As the substrate used in the present invention, any substrate can be used as long as it has the flexibility to be used 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.

The substrate used in the present invention is preferably an aluminum plate or a composite material of aluminum foil and other materials, and from the viewpoint of rigidity, an aluminum plate is particularly preferable.

In the present invention, the photosensitive lithographic printing plate prepared as described above is imagewise exposed, and then developed with a developer to dissolve the photosensitive layer and removed together with the silicone rubber layer thereon, so that the substrate or primer layer is removed. It is exposed as an image area and a waterless lithographic plate is formed.

In this case, it is preferable to dye the image area with a cationic dye such as Crystal Bioleft or Victoria Blue BOH during or after development.

The light source used for exposure may be any general-purpose light source including ultraviolet rays of 180 r+m or more and visible light, but carbon arc lamps, mercury lamps, xenon lamps, metal halide lamps, strobes, etc. are particularly preferred.

The developer used in the development process includes water, the following polar solvents, alkaline compounds such as amines, surface-active compounds, and, if necessary, aliphatic hydrocarbons (hexane, heptane, etc.).
"Isopar E, H, G" (trade name of aliphatic hydrocarbons manufactured by Esso Chemical), gasoline, kerosene, etc.), aromatic hydrocarbons (toluene, xylene, etc.), or halogenated hydrocarbons (triclene, etc.). It was added.

Polar solvent alcohols (methanol, ethanol, water, etc.) Ethers (methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl carpitol, ethyl carpitol, butyl carpitol, dioxane, etc.) Ketones (acetone, methyl ethyl ketone, etc.) Esters (acetic acid ethyl, methyl cellosolve acetate, cellosolve acetate, carpitol acetate, etc.) Development can be carried out using known methods such as rubbing with a developing band containing a developer as described above, or pouring a developer onto the plate surface and then rubbing with a developing brush. This can be done in various ways.

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

(Synthesis of Diazo Resin-1) 14.5 g of p-diazodiphenylamine sulfate was dissolved in 40.9 g of concentrated sulfuric acid under water cooling. 1 in this reaction solution
．． 0 g of rose formaldehyde was slowly added dropwise so that the reaction temperature did not exceed 10°C. Thereafter, stirring was continued for 2 hours under water cooling. This reaction mixture was heated for 500 m under water cooling.
1 of ethanol, and the resulting precipitate was filtered. After washing with ethanol, this precipitate was washed with 100mj! of pure water, and to this solution was added a cold concentrated aqueous solution containing 6.8 g of zinc chloride. The resulting precipitate was filtered, washed with ethanol, and dissolved in 150 ml 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 at 30°C all day and night to obtain diazo resin-1.

Weight average molecule of the diazo resin measured by GPC method in terms of styrene! (MW) is 1500, number average molecular weight is 50
It was 0.

(Examples 1 to 3, Comparative Examples 1 to 2) An aluminum plate with a thickness of 0.24 fl was immersed in a 3% aqueous sodium hydroxide solution to degrease it, washed with water, and then immersed in a 32% aqueous sulfuric acid solution at a temperature of 30°C for 5 A. /dl112 for 10 seconds, washed with water, immersed in a 2% sodium metasilicate aqueous solution at a temperature of 85°C for 37 seconds, further immersed in water at a temperature of 90°C (pH 8.5) for 25 seconds, and washed with water. , and dried to obtain an aluminum plate.

A primer layer composition having the following composition was applied to this aluminum plate, and after drying at 85° C. for 3 minutes, the entire surface was exposed to light at 1000 mJ/cm 2 using a high-pressure mercury lamp. It was further dried at 100° C. for 4 minutes to form a primer layer with a thickness of 0.8 μm.

(Primer layer composition) (1) Diazo resin - 18 parts (2) Copolymer resin of 2-hydroxyethyl methacrylate and methyl methacrylate in a molar ratio of 40/60 (M-4
．． 0XlO') 92 parts (3) γ-methacryloxypropyltrimethoxysilane
Part 2 (4) Methyl cellosolve 90
Part 0 Next, a photosensitive composition having the following composition was applied onto the above-mentioned brimer layer, and dried at 100°C for 2 minutes to a thickness of 0.3 μm.
An angry light layer was formed.

(Photosensitive composition) (11 diazo resin - 170 parts (2) 2-hydroxyethyl methacrylate, N-(4
-hydroxyphenyl) methacrylamide copolymer resin with a molar ratio of 30/70 (Mw・
4.8xlO') 30 parts (3) Victoria Pure Blue BOH (dye manufactured by Odugaya Kagaku ■) 1 part (4) Methyl cellosolve 900 parts Next, the following silicone rubber composition was applied on the above-mentioned irradiation layer to a certain thickness. It was applied and dried at 90°C for 10 minutes.

(Silicone rubber layer composition) Dimethylpolysiloxane having hydroxyl groups at both ends (molecular weight 52,000) 100
Part dibutyltin dilaurate 0.8 part Reactive silane compound listed below Each part (Table 1) C, H, S
i (OMe).

0 Isopar E (manufactured by Esso Chemical) 900 copies Next,
A single-sided matted polypropylene film having a thickness of 5 μm was laminated on the silicone rubber layer to obtain a waterless flat 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 performing standard development by immersing it in the following developer -■ for 1 minute, the surface of the plate material is rubbed with a pad impregnated with the developer to remove the silicone rubber layer and photosensitive layer in the unexposed areas. A printing plate with well reproduced halftone dots 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.

(Developer-1) β-anilinoethanol 0.5 parts Propylene glycol p-tert-butylbenzoic acid Potassium hydroxide polyoxyethylene lauryl ether Potassium sulfite Potassium metasilicate water (staining solution) 1.0 parts 1.0 parts 1.0 parts 0.1 parts 2.0 parts 3, 0 parts 91 parts Tulfit (manufactured by Kuraray Sobren Chemical ■, solvent) 20 parts Rheodol TW-0120 (manufactured by Kao ■, surfactant) Benzyl alcohol Victoria Pure Blue BOH Water 0 .5 parts 5.0 parts 1.0 parts 100 parts The results are shown in Table 1. Reactive silane compound is 0.5-10
It can be seen that the presence of a certain amount of oxide provides excellent scratch resistance and good image quality.

(Example-4) The binder of the photosensitive layer of Example-2 was a copolymer resin (M
A plate was obtained in the same manner except that W = 5.2 x 10').

When the scratch resistance was similarly evaluated, it was found to be poor despite the addition of 3 parts of the isocyanurate group-containing reactive silane compound at 5 g, indicating that it is essential that the photosensitive layer contains at least a hydroxyl group-containing polymer and a diaz resin. I found out something.

(Comparative Example-3) An attempt was made to obtain a plate in the same manner as in Example-1 except that the isocyanate group-containing reactive silane compound in the silicone layer was changed to aminopropyltrimethoxysilane, but the image quality was insufficient. I could only get something.

(Effects of the Invention) As explained in detail above, the present invention improves the adhesion between the photosensitive layer and the silicone layer, and as a result, provides a photosensitive lithographic plate that does not require soaking water and has excellent scratch resistance and image forming ability. I can do that.

Claims (1)

[Claims] The substrate has at least a primer layer, a photosensitive layer, and a silicone rubber layer in this order from the substrate side, and the photosensitive layer contains at least a hydroxyl group-containing polymer and a diazo resin, and the silicone rubber layer contains at least an organopolysiloxane and an isocyanurate. 1. A photosensitive lithographic printing plate that does not require dampening water and is formed from a silicone rubber composition containing a reactive silane compound having a group.