JPH0740133B2 - No dampening water required Photosensitive lithographic printing plate - Google Patents

Description

The present invention relates to a fountain solution-free photosensitive lithographic printing plate, and more particularly to a fountain solution-free photosensitive lithographic printing plate having improved scratch resistance.

[Conventional technology]

Conventionally, an aluminum plate has been used as a support for a lithographic printing plate. It has a hydrophilic surface,
This is because the surface treatment is easy and the mechanical strength of the printing plate is excellent. But aluminum is expensive,
It has the drawback of increasing the price of the printing plate. As a support for eliminating such a price defect, Japanese Patent Laid-Open No. 60-19639
No. 6, JP-A-58-112896 and JP-A-58-53491 disclose composite supports formed by laminating aluminum foils. However, with a printing plate using this support, dampening water soaks in during printing, and the support is likely to swell and peel off.If a core material and adhesive without such defects are used, it is difficult to reduce the price. There was a problem of becoming.

For the above reasons, an aluminum sheet plate has been generally used as a support for a photosensitive lithographic printing plate that does not require a fountain solution.

However, since such an aluminum sheet is plastically deformed by an external pressure, it has a drawback that it is easily scratched, that is, its scratch resistance is extremely poor. Therefore, the silicone rubber layer is destroyed by the force from the outside,
There is a problem that scratches and unevenness are generated, and ink is attached to this portion during printing, which causes printing stains. In order to improve the scratch resistance, Japanese Patent Application No. 61-35755 discloses a technique of providing a primer layer between the photosensitive layer and the aluminum sheet to serve as a cushion. The present invention provides a silicone rubber layer by providing a primer layer as a cushion layer with a sufficient thickness.
Although it is intended to suppress the destruction of the photosensitive layer, the effect is not yet sufficient.

Further, the aluminum sheet is heavy, and it is difficult to handle such that it is easy to cut a hand at the edge of the aluminum sheet.

Further, when the aluminum surface is used as it is, there is a defect that it is difficult to identify fine halftone dots due to the metallic luster of aluminum and streaks in the rolling direction during plate inspection.

[Problems to be solved by the invention]

Therefore, an object of the present invention is to provide a photosensitive lithographic printing plate that does not require fountain solution, has excellent scratch resistance, is lightweight, is easy to handle, and has excellent plate inspection property.

[Means for solving problems]

The above-mentioned object is a photosensitive lithographic printing plate not requiring fountain solution having a photosensitive layer and a silicone rubber layer on a support, and the support is a laminate comprising a cushion layer and metal layers laminated on both sides thereof. This is achieved by a photosensitive lithographic printing plate that does not require a fountain solution.

Hereinafter, each component of the photosensitive lithographic printing plate not requiring fountain solution (hereinafter referred to as waterless PS plate) of the present invention and the plate making method will be described in detail.

<Support> The support used in the present invention is composed of a cushion layer and metal layers laminated on both surfaces thereof.

<Metal layer> The metal layer is used on both sides in terms of the feel (stiffness) and curl of the plate. As the material of the metal layer, aluminum, iron,
Examples include galvanized iron, tin plate, and copper plate, but aluminum is most preferable from the viewpoint of compatibility with the plate cylinder, weight, and rust resistance. Aluminum material is appropriately selected according to the purpose,
A hard aluminum foil is more preferable so as not to impair the feel (stiffness) of the printing plate.

It is desirable that the thickness of the metal layer be appropriately selected from the range of 10 to 50 μ. When the thickness is less than 10 μm, the strength of the printing plate decreases, while when it is more than 50 μm, the function as a cushion layer composed of the adhesive layer and / or the core layer is not sufficiently exhibited, and the weight becomes heavy, and the handleability is increased. However, it is not preferable in terms of economy.

When an aluminum sheet is used as the metal layer, the surface of the support is preferably a surface roughened by the lap rolling method during the production of the aluminum foil. The normal average surface roughness is suitably in the range of 0.3 to 0.4 μ. Further, in order to improve the adhesion with the photosensitive layer, the surface of the metal layer may be subjected to a treatment such as graining, anodizing treatment, or chemical conversion treatment. The graining treatment may use any of a mechanical method, a chemical method and an electrochemical method. Moreover, you may combine those methods. A known method can be used for the anodizing treatment. Particularly preferable graining and anodic oxidation methods are described in detail in JP-B Nos. 51-33444, 46-27481 and 55-12877.

Also, as an alternative treatment to anodization, titanate treatment,
A chemical conversion treatment such as a chromate treatment may be performed.

<Cushion Layer> The cushion layer is composed of the adhesive layer alone, the core layer alone, or the adhesive layer and the core layer described below. As the cushion layer, Shimadzu Corporation, Shimadzu dynamic ultra-micro hardness tester DUH-50, opposite ridge angle 115 °, tip curvature radius 0.10 μm
When the indentation depth is measured using the following diamond indenter, it can be used as long as it has a larger value compared to the case of using the metal sheet alone, but when the load is 30 g, the indentation depth is 13 A material having a value of about 20 μ is suitable.

<Adhesive Layer> The adhesive layer is for fixing the core layer and the metal layer or for forming a cushion layer by itself, and is usually prepared by a laminating method. As a laminating method, a wet method,
Methods well known in the art such as a dry method, a hot melt method and an extrusion method can be used. In order to make the adhesive layer act as a cushion layer, a method of extruding a film having a sufficient thickness by an extrusion method and thermocompression-bonding with the core layer is preferable. As the film, low-density polyethylene, high-density polyethylene, polypropylene, etc. can be used. Used. The thickness of the film layer is appropriately in the range of 5 to 80 μm, and if it is thinner than 5 μm, the waterproofness and adhesiveness to the core layer become insufficient.
If it is made thicker than μ, further improvement in performance can no longer be expected and only the cost will increase.

Further, when the core layer and the adhesive layer are adhered, an anchor coating agent may be applied to the adhesive surface in order to improve the adhesive strength. In particular, polyethylene, polypropylene and the like have extremely poor adhesiveness because of their inert structure and non-polarity. In order to improve the adhesiveness of such materials, when polyethylene, polypropylene, etc. are melted, they are forcibly air-oxidized to impart polarity, and at the same time, an anchor coating agent is applied to the core material to perform adhesion promoting treatment. The method is generally taken. Preferable anchor coating agents include organic titanium-based, isocyanate-based, polyethyleneimine-based, and polybutadiene-based anchor coating agents.

Alkyl titanate is a typical organic titanium-based anchor coating agent, and tetraisopropyl titanate, tetrabutyl titanate, tetrastearyl titanate, 2-ethylhexyl titanate and the like can be mentioned, but the disadvantage is that pot life is short because of rapid hydrolysis. There is.

Examples of the isocyanate-based anchor coating agent include toluene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and isophorone diisocyanate. The isocyanate type has a longer pot life than alkyl titanate and is excellent in other performances, and is used in the largest amount.

In order to improve the adhesive strength between the core layer and the adhesive layer, corona discharge treatment of the surface, or further, Surlyn manufactured by DuPont, USA,
An ionomer resin such as high milan manufactured by Mitsui Polychemical Co., Ltd. may be applied.

On the other hand, there is also a method of bonding two metal sheets with an adhesive to form a support, and in this case, the adhesive functions as an adhesive layer. As a typical example of such an adhesive,
Examples include urethane rubber-based adhesives, chloroprene-based adhesives, nitrile rubber-based adhesives, styrene rubber-based adhesives, and butyl rubber-based adhesives.

When a material having a large elastic deformation is used for the core layer, in addition to the above adhesive, an adhesive composed of a copolymer of vinyl acetate and an unsaturated acid containing 2-ethylhexyl acrylate as a main monomer, methylol diacetone acrylamide, butoxymethyl Acrylamide, an adhesive obtained by copolymerizing a cross-linking monomer such as methacrylic acid butylamino ester, and further adding a water-soluble or water-dispersible epoxy compound, polyvinylpyrrolidone, an adhesive consisting of a copolymer of methyl vinyl ether maleate, An adhesive composed of a copolymer emulsion of methacrylic acid monoester of polyoxyethylene and an alkyl acrylate, an adhesive prepared by adding dextrin or polyvinyl alcohol to a polyvinyl acetate emulsion, and further epoxy, polyurea. Solution of down-based resin in an organic solvent may also be used.

When the cushion layer is composed of the core layer and the adhesive layer, the thickness of the adhesive layer is not particularly limited, but is 5 to 80 μ, generally 20 μ.
The following is sufficient. When the cushion layer is composed of the adhesive layer alone, the thickness of the adhesive layer is appropriately 20 to 80 μm.

<Core layer> The core layer is made of paper (synthetic paper, waterproof paper), plastic film, metal sheet (iron, aluminum, copper, etc.), flexible rubber sheet, non-woven fabric, woven fabric and these materials, as well as iron, aluminum and copper. There is a composite with a metal sheet such as.

In conventional PS plates that require fountain solution, the core layer must have excellent water resistance, and paper is generally unsuitable.

The waterless PS plate of the present invention does not use dampening water, and since the plate making process is also short, there is little need for water resistance,
Therefore, it has become possible to use paper as the core layer. Paper is also preferable from the economical point of view, and it is possible to realize a support that is lightweight, inexpensive, and has no problem in practical printing. The paper is also
It is more elastic than metal sheets and is also advantageous in terms of scratch resistance. However, the paper used as the core layer is
A water resistant material is preferable in terms of strength, and a melamine formalin resin, a urea formalin resin, a polyamide epichlorohydrin resin, or the like, a high-quality paper wet-reinforced with carbon fiber, a resin-coated paper, or the like is particularly preferable. Coated paper finished with a super calendar or the like is also preferable in order to have surface smoothness.

The thickness of the cushion layer cannot be generally determined because it varies depending on the material used, but it is generally about 5μ to about 250μ as the total thickness of the cushion layers contained in the support.
The range is appropriate. As it becomes thinner than 5μ, the function as a cushion layer deteriorates. On the other hand, 250
When the thickness is larger than μ, the strength of the support is lowered, the handleability is lowered, and the weight is increased. A more preferable range of the thickness of the cushion layer is 20μ to 200μ.

<Primer layer> The waterless PS plate of the present invention preferably has a primer layer on a support. The primer layer strengthens the adhesion between the support and the photosensitive layer, and when the primer layer is exposed after exposure and development, it has good developer resistance and is easily dyed with a dye to provide plate inspection property, and the ink It is desirable to be receptive. Hardened epoxy resin, urethane resin, hardened gelatin, etc. are mentioned as a thing satisfying such a condition.

Typical examples of epoxy resins are as follows.

(1) Reaction product of bisphenol A and epichlorohydrin (2) Reaction product of novolak resin and epichlorohydrin (3) Reaction product of bisphenol F and epichlorohydrin (4) Reaction product of tetrabromobisphenol A and epichlorohydrin (5) Cyclic Aliphatic Epoxy Resin (Compound Having Cyclohexene Oxide Group, Tricyclodecene Oxide Group, Cyclopentene Oxide Group) (6) Glycidyl Ester Epoxy Resin (Reaction Product of Polycarboxylic Acid and Epichlorohydrin) (7) ) Glycidylamine-based epoxy resin (reaction product of amine and epichlorohydrin) (8) Heterocyclic epoxy resin (hydantoin-type epoxy resin obtained by glycidylating hydantoin ring and triglycidyl group) Other than the above, as the epoxy resin, any known epoxy resin, that is, any epoxy resin having at least one epoxy group per molecule on average can be used, but particularly preferable ones are shown in (1). The bisphenol A-based epoxy resin represented by the following general formula has various epoxy equivalents, and the epoxy equivalent of 180 to 4000 is preferable.

Typical examples of the acid anhydride used as a curing agent for the above epoxy resin are as follows.

(1) Aromatic acid anhydrides (phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, 3,3 ', 4,4'-benzophenone tetracarboxylic acid anhydride, etc.) (2) Cyclic fat Aromatic acid anhydrides (maleic anhydride, succinic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic acid anhydride, alkenylsuccinic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylcyclohexanetetracarboxylic acid Acid anhydrides, etc.) (3) Aliphatic acid anhydrides (polyadipic acid anhydride, polyazelaic acid anhydride, polysebacic acid anhydride, etc.) (4) Halogenated acid anhydrides (chlorendic acid) Anhydrides, tetrabromophthalic anhydride, etc.) Tertiary amines used as curing accelerators when curing acid anhydrides of epoxy resins Representative examples of compounds are those such as the following.

(1) Aliphatic tertiary amines (including tetramethylguanidine, alkyl-tert-monoamine, triethanolamine, etc.) (2) Cyclic aliphatic tertiary amines (N, N'-dimethylpiperazine, triethylenediamine) , Etc.) (3) Aromatic tertiary amines (including pyridine, picoline, etc.) (4) Aliphatic tertiary amines having an aromatic ring (benzyldimethylamine, 2- (dimethylaminomethyl)) Phenol, 2,4,6-tris (dimethylaminomethyl) phenol, etc.) The acid anhydride curing agent is added in an amount of 2 to 10 relative to the epoxy resin.
It is in the range of 0% by weight. A particularly preferred range depends on the type of epoxy resin and acid anhydride used, but one example is an epoxy resin having an epoxy equivalent of 500 and an acid anhydride equivalent of 150.
When the acid anhydride of 10 is used, 10 to 50% by weight is suitable.

The addition amount of the tertiary amine compound which is a curing accelerator is in the range of 0.5 to 30% by weight based on the epoxy resin. It is particularly preferably in the range of 5 to 20% by weight.

The above-mentioned epoxy resin, acid anhydride and tertiary amine compound are dissolved in a suitable organic solvent, coated on a support, and then heat-cured at a temperature of 80 to 150 ° C. A suitable thickness of the primer layer is 0.1 to 50 µ, more preferably 0.5 to 10 µ.

If necessary, a filler such as titanium oxide, an antihalation agent, a dye for imparting printout property, or an acid generator may be appropriately mixed and used in the primer layer.

<Photosensitive Layer> The photosensitive layer used in the present invention may be any layer as long as it changes the solubility in a developing solution before and after exposure.

The compound or composition constituting such a photosensitive layer includes the following.

(1) A unsaturated monomer or an oligomer thereof, which has a boiling point of 100 ° C. or higher and is non-volatile at room temperature, a photopolymerization initiator, a thermal polymerization inhibitor, and, if necessary, a filler for imparting shape retention at room temperature and a little. A photopolymerizable composition containing an additive.

As unsaturated monomers, ethylene glycol di (meth) acrylate, polyethylene glycol di (meth)
A series of acrylic acid esters such as acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate, 1-chloro-2-hydroxyethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, Methacrylic acid esters, acrylamide derivatives such as ethylenebisacrylamide, N-methylolacrylamide, and methoxymethylacrylamide can be used.

As the photopolymerization initiator, a benzophenone derivative, a benzoin derivative, an anthraquinone derivative, an aldehyde, a ketone, a sulfur compound, a halogen compound, or a dye such as methylene blue or riboflavin can be used.

As the thermal polymerization inhibitor, hydroquinone derivatives, phenol derivatives, nitro-substituted benzenes, tertiary amines, and phenothiazine derivatives are used.

Fillers or additives include fine powders of inorganic materials such as colloidal silica, calcium carbonate, magnesium carbonate, iron oxide, polyvinyl acetate, poly (meth) acrylic acid ester, polyethylene having a molecular weight of several thousand, polypropylene, and pyrivinyl chloride. Examples include vinyl polymers such as polyvinylidene chloride, resol phenolic resins before curing, urea resins, melamine resins, epoxy resins, unsaturated polyester resins, and the like.

(2) In the main chain or side chain of the polymer A composition comprising a polymer compound containing.

As a photosensitive group on the polymer main chain or side chain Containing a photosensitive polymer such as polyesters, polyamides, and polycarbonates containing (for example, US Pat. Nos. 3,030,208, 3,707,373 and 3,45).
Compounds as described in each of the 3,237 specifications);
Photosensitive polyesters derived from (2-properidene) malonic acid compounds such as cinnamylidene malonic acid and bifunctional glycols as main components (for example, US Pat. Nos. 2,956,878 and 3,173,787 Sensitized polymers such as those described in U.S. Pat. No. 4,962,819; cinnamic acid esters of hydroxyl-containing polymers such as polyvinyl alcohol, starch, cellulose and the like (eg US Pat.
690,966, No. 2,752,372, No. 2,732,301 and the like photosensitive polymers as described in each specification), further described in JP-A-58-25302, 59-17550 Polymers and the like are included.

(3) Photocurable diazo resin or azide resin, and if necessary, a photosensitizer and some filler additives.

Examples of the photocurable diazo resin include zinc chloride double salt of a condensation product of a diazo amine such as paradiazophenylamine, paradiazomonoethylaniline, paradiazobenzylethylaniline and formaldehyde.

Examples of the photocurable azide resin include polyvinyl alcohol azidophthalate ester, azidobenzoic acid ester, styrene-maleic anhydride copolymer, and aromatic azide alcohol such as β- (4-azidophenol) ethanol ester. Can be given.

As the photosensitizer, the filler, and the additives, those mentioned in the example (1) can be used.

(4) A composition comprising an o-quinonediazide compound.

A particularly preferred o-quinonediazide compound is an o-naphthoquinonediazide compound and is described, for example, in U.S. Pat. No. 2,766,11.
No. 8, No. 2,767,092, No. 2,772,972, No. 2,859,1
No. 12, No. 2,907,665, No. 3,046,110, No. 3,046,
No. 111, No. 3,046,115, No. 3,046,118, No. 3,04
No. 6,119, No. 3,046,120, No. 3,046,121, No. 3,0
No. 46,122, No. 3,046,123, No. 3,061,430, No. 3,
102,809, 3,106,465, 3,635,709, and
It is described in a large number of publications including the respective specifications of 3,647,443, and these can be preferably used. Among these, o-naphthoquinone diazide sulfonic acid ester or o-naphthoquinone diazide sulfonic acid ester of aromatic hydroxy compound, and o-naphthoquinone diazide sulfonic acid amide or o-naphthoquinone diazide carboxylic acid amide of aromatic amine compound are particularly preferable. , For example benzoquinone-1,2-diazide sulfonic acid,
Ester of naphthoquinone-1,2-diazide sulfonic acid and polyhydroxyphenyl (hereinafter ester also includes partial ester), naphthoquinone-1,2-diazide-4-
Sulfonic acid or naphthoquinone-1,2-diazide-5-
Ester of sulfonic acid and pyrogallol acetone resin,
Benzoquinone-1,2-diazidesulfonic acid or naphthoquinone-1,2-diazidesulfonic acid and ester of novolac type phenol formaldehyde resin or novolac type cresol formaldehyde resin, poly (p-aminostyrene) and naphthoquinone-1,2- Amide of diazido-4-sulfonic acid or naphthoquinone-1,2-diazide-5-sulfonic acid, poly-p-hydroxystyrene and naphthoquinone-1,2-diazide-4-sulfonic acid or naphthoquinone-1,2-diazide-5 -Ester of sulfonic acid, polyethylene glycol and naphthoquinone-1,2-diazide-4-sulfonic acid or ester of naphthoquinone-1,2-diazide-5-sulfonic acid, polymer amine and naphthoquinone-1,2-diazide-4 -Sulfonic acid or naphthoquinone-1,2-diazide-5-sulfo Amides of acids, esters of polymethacrylic acid p- hydroxyanilide and naphthoquinone-1,2-diazide-4-sulfonic acid or naphthoquinone-1,2-diazide-5-sulfonic acid,
Natural resin rosin modified with amine and naphthoquinone-
1,2-diazide-5-sulfonic acid amides, epoxy resins from bisphenol A and propylene oxide and naphthoquinone-1,2-diazide-5-sulfonic acid esters, (meth) acrylic acid and dihydroxyphenyl monoesters Polymer and naphthoquinone-1,2-diazide-4
-Sulfonic acid or naphthoquinone-1,2-diazide-5
-Sulfonic acid ester, polymer of condensation product of aminoisophthalic acid diallyl ester and naphthoquinone diazide sulfonic acid, quinone diazide sulfonic acid ester of polycarbonate or quinone diazide crosslinked with isocyanate, bisphenol A and naphthoquinone- 1,2-Diazide-4-sulfonic acid or naphthoquinone-1,2-diazide-5-sulfonic acid ester, naphthoquinone-1,2-diazide-5-sulfonic acid and phenol, phenols such as p-cresol, ethyl , Esters with alcohols such as propyl, butyl and amyl alcohol, and acid amides with naphthoquinone-1,2-diazide-5-sulfonic acid and amines such as aniline and p-hydroxyaniline.

Of these, particularly preferred photosensitive layers are the photopolymerizable composition (1) and the photodimerization type (2).

The thickness of the photosensitive layer as described above is preferably as thin as possible as long as the photosensitive layer in the image area and the silicone rubber layer can be removed in the developing step after image exposure, but it is a general guideline. Is less than 1μ, especially 0.1-0.5μ
It is desirable and preferable to be selected from the range below.

Further, as described in JP-B-54-26923 or JP-B-61-54222, when a developing method for removing only the silicone rubber layer in the image area is adopted, the thickness of the photosensitive layer is Wide range is possible, from about 0.1μ to about 100
μ, preferably 0.5 μ to 10 μ.

<Silicone Rubber Layer> The silicone rubber layer used in the present invention is mainly composed of a linear organic polysiloxane having the following repeating unit and having a molecular weight of several thousand to several hundred thousand.

Here, R is an alkyl group having 1 to 10 carbon atoms or a phenyl group, and preferably 60% or more of R is a methyl group. Such a linear organic polysiloxane is generally made into a crosslinked silicone rubber by adding a reactive crosslinking agent. Crosslinking agents used for so-called room temperature (low temperature) curable silicone rubbers include acetoxysilane, ketoximesilane, aminoxysilane, amidosilane, alkoxysilane, and hydroxy having or not having a monovalent organic group bonded to a silicon atom. There are silanes such as silanes, siloxanes which are condensation products of these having a low degree of polymerization, and organo-hydrogenpolysiloxanes. Further, in order to improve the adhesive force between the photosensitive layer / silicone rubber layer and prevent the interlayer adhesive force from being deteriorated even after a long period of time, a reactive silane compound having an allyl isocyanurate group, a reactive silane compound having an aminoalkyl group, etc. May be added to the silicone rubber composition.

The addition amount of the reactive crosslinking agent and / or the reactive silane compound contained in the silicone rubber layer is preferably 0.
05-10%, more preferably 0.1-5% is selected. It is also possible to use a mixture of these adhesive components.

In addition, a small amount of an organic tin compound or the like is generally added to the silicone rubber layer as a catalyst.

The thickness of the silicone rubber layer is preferably as thin as possible from the point of tone reproducibility. Also, from the viewpoint of printing durability and printing stains, a certain thickness is required, so 0.5 to 10μ is usually appropriate, 1.0 to 3.0μ is desirable.

The waterless PS plate of the present invention basically has the constitution as described above, but an adhesive layer may be interposed between the photosensitive layer and the silicone rubber layer, if necessary. As such an adhesive layer, various reactive crosslinking agents and silane coupling agents are used. Among them, effective ones include a silane coupling agent having an oxime group, a reactive silicone compound having an aminoalkyl group, a reactive silane compound having an allyl isocyanurate group, and an organic titanate compound (titanium-based primer).

In principle, the thickness of the adhesive layer should be a monolayer or more,
The range of 10 mμ to 0.5 μ is selected in the actual coating operation. If it is too thick, not only is it economically disadvantageous, but it also adversely affects the penetration of the developing solution into the photosensitive layer and deteriorates the image reproducibility.

Furthermore, if necessary, a protective film may be provided on the silicone rubber layer of the waterless PS plate of the present invention.

<Plate-making method> The waterless PS plate according to the present invention is exposed through a transparent original image and then developed with a developer capable of dissolving the photosensitive layer in the non-image area, and the photosensitive layer in the non-image area and the silicone rubber layer thereon. Are removed to form a plate without water.

Alternatively, a developing method in which substantially only the silicone rubber layer in the image area is removed can be used, and specifically, Japanese Patent Publication No.
No. 61-54222, JP-A-54-89805, and 55-156947.
No. 60-60051, the method described in each publication can be used.

Examples of light sources for image exposure include ultra-high pressure mercury lamps, carbon arc lamps, metal halide lamps, xenon lamps,
Chemical lights, fluorescent lights, sunlight, etc. are used.

As the developing solution used in the present invention, a known developing solution for a waterless PS plate can be used. For example, aliphatic hydrocarbons (hexane, heptane, “isopar E, H, G”)
(Trade name of aliphatic hydrocarbons manufactured by Esso Chemical Co., Ltd.) or gasoline, kerosene, etc., aromatic hydrocarbons (toluene, xylene, etc.) or halogenated hydrocarbons (tricklene, etc.) with the following polar solvent added Is preferred.

Alcohols (methanol, ethanol, water, etc.) Ethers (methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl carbitol, ethyl carbitol, butyl carbitol, dioxane, etc.) Ketones (acetone, methyl ethyl ketone, etc.) Esters (ethyl acetate, ethyl acetate, (Methyl cellosolve acetate, cellosolve acetate, carbitol acetate, etc.) Further, a dye such as crystal violet or acetrazone red may be added to the developer to dye the image area simultaneously with the development.

The development can be carried out by a known method such as rubbing with a developing pad containing the above-mentioned developing solution or rubbing with a developing brush after pouring the developing solution onto the plate surface. As a result, the silicone rubber layer and the photosensitive layer in the image area are removed, the surface of the primer layer is exposed, and the area becomes the ink receiving area.

<Examples> Hereinafter, the present invention will be described in more detail with reference to Examples.

Roughened by lap rolling, width 800 m / m, thickness 20 ~
Aluminum foil with 80μ and average roughness 0.3-0.5μ (IN-30)
Then, an adhesive layer was provided on one or both of water resistant paper (PHO manufactured by Fuji Tokushu Paper Co., Ltd.) or a steel plate, and they were laminated by a laminating machine so that the roughened surface became the surface.

As the adhesive layer, samples using polypropylene film manufactured by Mitsubishi Petrochemical (Examples 1, 2, 3, 4, 5, 6,
In 7), the molten polypropylene resin was pressure-bonded and cooled between the aluminum foil and the waterproof paper by the extrusion laminating method to bond them. To increase the adhesive strength,
As a pretreatment, an anchor coating agent was applied to the aluminum surface on the adhesive side. As the anchor coating agent, an isocyanate type is selected, and Titabond-120 manufactured by Nippon Soda Co., Ltd.
~ 5 g / m ^{2 was} applied. Samples using a butyl rubber sheet for the adhesive layer (Examples 8 and 9) were prepared by applying a nitrile rubber / brominated butyl rubber blend adhesive to the butyl rubber surface,
On top of that, a general rubber adhesive was overcoated. On the aluminum surface, the above-mentioned isocyanate-based anchor coating agent was applied in an amount of 4 to 5 g / m ² and heat-pressed.

The samples (Examples 10 and 11) using the adhesive (polyurethane type) for the adhesive layer were dry lamination method, the adhesive was applied to the aluminum foil by the gravure coating method, and the organic solvent was evaporated by a drier to obtain water resistance. Paper and 80 ℃
It was thermocompression bonded.

Next, the following primer layer composition was applied so as to have a dry weight of 2.0 g / m ² , and was heated and cured at 120 ° C. for 5 minutes.

・ Epicoat 1001 (Bisphenol A epoxy resin manufactured by Shell Chemical Co., Ltd., epoxy equivalent is 450-500) 100 parts by weight ・ Methyltetrahydrophthalic anhydride 36 parts by weight Acid ・ 2,4,6-Tris (dimethylamido 10 parts by weight nomethyl) phenol ・Methyl cellosolve acetate 600 parts by weight Toluene 600 parts by weight Methyl ethyl ketone 600 parts by weight On the aluminum plate coated with the above primer layer, the following photosensitive composition is applied to a dry weight of 0.25 g / m ² and dried. did.

Photosensitive unsaturated polyester obtained by 1: 1 polycondensation of p-phenylenediacrylic acid ester and 1,4-dihydroxyethyloxycyclohexane 10 parts by weight 1-methyl-2-benzoylmethylene-β naphthothiazoline 0.6 parts by weight Part Sumitone Cyanine Blue VH 514 (Sumitomo Chemical Phthalocyanine Blue Pigment) 2 parts by weight Methyl Cellosolve Acetate 600 parts by weight Toluene 300 parts by weight Next, the following silicone rubber composition on the above-mentioned photosensitive layer in a dry weight of 2.0 g It was coated so as to be / m ² and dried to obtain a silicone rubber cured layer.

Dimethyi having hydroxyl groups at both ends 100 parts by weight Lupolysiloxane (molecular weight of about 600,000) Methylhydrogen polysiloxane having trimethylsilyl groups at both ends of 3.5 parts by weight (molecular weight of about 2500) 1-Methoxysilylpropyl-3.3 parts by weight 3,5 -Diallyl isocyanurate Dibutyltin dioctanoate 3.3 parts by weight Isopar G (manufactured by Esso Chemical Co., Ltd.) 2000 parts by weight The surface of the silicone rubber layer obtained as described above is laminated with a matte polypropylene film having a thickness of 12 μ, without water. I got the PS version.

ET26V UDNS ULTRA-PLUS FLIP-TOP PLATE MAKER made by Nuark Co., Ltd.
After 30 counts of exposure, the laminate film was peeled off, and a developer comprising 90 parts by weight of Isopar H (manufactured by Esso Kagaku), 7 parts by weight of diethylene glycol monobutyl ether, 3 parts by weight of diethylene glycol monoethyl ether and 5 parts by weight of diethyl succinate. After immersing in a sheet for 1 minute and rubbing lightly with a developing pad, the unexposed portion of the photosensitive layer and the silicone rubber layer were removed. In this way, a fountain solution-free lithographic printing plate that faithfully reproduced the image of the positive film was obtained over the entire surface of the printing plate.

Load 10 using HEIDON scratch strength tester
After scratching from above the silicone rubber layer with a sapphire needle at 0 to 500 g, attach it to the Heidelberg GTO printing machine without dampening water supply device, and use TOYO KING ULTRA TKU AQUALES G ink Printed. The results are shown in Table 1.

The scratch resistance was determined by the degree of occurrence of print stains on the scratched scratches when 1,000 sheets were printed by the above printing machine.

The indentation amount of the support for a constant load is measured by Shimadzu Dynamic Ultra-micro Hardness Tester DUH-50 manufactured by Shimadzu Corporation using a diamond indenter with a dihedral angle of 115 ° and a tip curvature radius of 0.10μ or less at a load of 30g. Was measured.

As shown in Table 1, the waterless PS plate of the present invention has a significantly improved scratch resistance as compared with the comparative example using a support made of aluminum only. This made it light and easy to handle, and the surface was roughened by superposition and rolling, and the effect of improving plate inspection was also created.

[Effect of the Invention] According to the present invention, by using a laminated support comprising metal layers on both sides of an adhesive layer or core layer having cushioning properties, scratch resistance is improved and silicone layers and photosensitive layers are improved. Destruction is suppressed and printing stains can be prevented. Further, the problems regarding the weight feeling when handling the aluminum support and the difficulty in handling such as easy cutting of the hand due to the edges of the aluminum sheet are solved, which have been problems with lithographic printing plates and the like.

Claims (5)

[Claims] 1. A photosensitive lithographic printing plate which does not require fountain solution and has a photosensitive layer and a silicone rubber layer on a support, the support comprising a cushion layer and metal layers laminated on both sides thereof. A photosensitive lithographic printing plate that does not require fountain solution. 2. The photosensitive lithographic printing plate not requiring fountain solution according to claim 1, wherein the cushion layer comprises a core layer and adhesive layers laminated on both sides thereof. 3. A photosensitive lithographic printing plate not requiring fountain solution according to claim 1 or 2, wherein the metal layer is an aluminum sheet. 4. The photosensitive lithographic printing plate not requiring fountain solution according to claim 3, wherein the surface of the aluminum sheet is a surface roughened by a lap rolling method. 5. A photosensitive lithographic printing plate which does not require a fountain solution, in which a primer layer, a photosensitive layer and a silicone rubber layer are sequentially provided on a support, the support being a cushion layer and a metal laminated on both sides thereof. A photosensitive lithographic printing plate not requiring dampening water, which is a laminate comprising layers.