JPS62194255A - Photosensitive lithographic printing plate without requiring damping water - Google Patents

Abstract

PURPOSE:To obtain a waterless PS plate having the printing resistance and scratching resistance equiv. to the printing resistance and scratching resistance of the conventional PS plate by making the thickness of a primer layer smaller than the thickness heretofore used. CONSTITUTION:The thickness of the primer layer 2 of a photosensitive lithographic printing plate which does not require damping water and has the primer layer 2, a photosensitive layer 3 and a silicone rubber layer 4 in this order on a base 1 is specified to 6-100mu. The primer layer formed by using an epoxy resin or polyurethane resin and curing the same by heating using a suitable curing agent is used. The resistance to scratching and wear is thereby improved even if the thickness of the photosensitive layer is made smaller and there is the advantage that the resultant waterless plate has high print resisting power.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides high printing durability, high scratch resistance, high sensitivity, high developability, and high This invention relates to a photosensitive lithographic printing plate that does not require dampening water (hereinafter referred to as a waterless PS plate) with improved practicality such as oil sensitivity.

[Prior art]

Various waterless PS plates having a photosensitive layer and a silicone rubber layer on a support have already been proposed (for example, Japanese Patent Publication No. 44-23042, Japanese Patent Publication No. 46
-16044, Special Publication No. 51-17081, Special Publication No. 51
No. 4-26923, Japanese Patent Publication No. 56-80046, Japanese Patent Publication No. 55-22781). Plate making methods using this type of waterless PS plate can be roughly divided into the following two types of methods. One method is to dissolve the photosensitive layer in the image area with a developer and remove the silicone rubber layer above it to form the image area (Japanese Patent Publication No. 16044/1983). In this method, a photoadhesive photosensitive layer (in the case of a positive type) or a photoremovable photosensitive layer (in the case of a negative type) is provided as a photosensitive layer, and only the portions of the silicone rubber layer that are not photoadhered by image exposure are swelled and removed. A method of selectively swelling and removing only the silicone rubber layer on the photosensitive layer, that is, swelling and removing only the silicone rubber layer in the area where photo-peeling occurred due to image exposure (Japanese Patent Publication No. 54-26923 and Japanese Patent Application Laid-Open No. 56-80046) No.). In the former method, even if the adhesive strength between the silicone rubber layer and the photosensitive layer is designed to be sufficiently high, the photosensitive layer is eluted and removed, so poor image formation and poor development are less likely to occur. Even when manufacturing a waterless PS plate that does not have a cover film on the rubber layer, it is possible to manufacture a waterless PS plate with stable adhesion strength of the silicone rubber layer, scratch resistance, and abrasion resistance. In addition, waterless plates obtained from such waterless PS plates can be expected to have high printing durability.

However, the image area of this waterless plate has to be a relatively deep recess formed by removing both the photosensitive layer and the silicone rubber layer, and the ink must be sufficiently deposited in this recess during printing. In order to do this, there was a problem in that it was necessary to increase the amount of ink supplied to the printing plate, or to apply a thick layer of ink. On the other hand, in the latter method, the image area is a relatively shallow recess formed by removing only the silicone rubber layer, so the ink can be applied thinly.
The silicone rubber layer has sufficient scratch resistance and abrasion resistance, and the adhesive strength between the silicone rubber layer and the photosensitive layer is increased in order to make a waterless plate with printing durability. Since it is inevitably difficult to remove (develop) the silicone rubber layer in the image area, the scratch resistance and abrasion resistance of the silicone rubber layer are insufficient, and the waterless plate has low printing durability. The essential drawback was that only a waterless PS version could be obtained.

In order to solve the above-mentioned problems, a method has been proposed in which a waterless PS plate is used, in which an extremely thin photosensitive layer is provided on a support and a silicone rubber layer is provided thereon (JP-A-6
O-229031). According to the above method, the adhesive strength between the silicone rubber layer and the photosensitive layer can be sufficiently increased, and even in the case of a waterless PS plate in which a cover film is not provided on the silicone rubber layer, the adhesive strength of the silicone rubber layer can be increased sufficiently. It has stable scratch resistance and wear resistance,
A waterless plate obtained from such a waterless PS plate can be expected to have high printing durability. Moreover, since the photosensitive layer is thin, the image area becomes a concave area where the silicone rubber layer and photosensitive layer are removed, but since the depth is only substantially equivalent to the thickness of the silicone rubber layer, a thin layer of ink cannot be applied. It is fully printable.

However, even waterless PS plates with sufficient performance are susceptible to scratches during the development process or when installing the plate on a printing machine, making them difficult to handle compared to PS plates that use regular dampening water. There was a hearing.

[Problem that the invention seeks to solve]

Therefore, an object of the present invention is to provide a waterless PS plate that can be coated with ink in a thin layer and has printing durability and scratch resistance comparable to conventional PS plates.

[Means for solving problems]

The present invention provides a photosensitive lithographic printing plate that does not require dampening water, in which a primer layer, a photosensitive layer, and a silicone rubber layer are arranged in this order from the support side, and when the thickness of the primer layer is thicker than the thickness conventionally used, This was done based on the knowledge that the above objectives could be effectively solved.

That is, the present invention provides a photosensitive lithographic printing plate that does not require dampening water and has a primer layer, a photosensitive layer, and a silicone rubber layer in this order on a support, in which the thickness of the primer layer is 6.
To provide a photosensitive lithographic printing plate that does not require dampening water and has a thickness of 100 μm.

The basic structure of the waterless PS plate of the present invention, as shown in the cross-sectional view in FIG. When this is imagewise exposed and developed, a waterless plate shown in FIG. 2 is obtained.

In FIG. 2, the image area 4A is a recess where both the silicone rubber layer and the photosensitive layer have been removed and the surface of the primer layer 2 is exposed, and 4B is a non-image area.

Hereinafter, each component and plate-making method of the waterless 28 plate of the present invention will be explained in detail.

Support: The support must be flexible enough to be set in a normal lithographic printing machine, etc., and must be able to withstand the load applied during printing. Typical examples include metal plates such as aluminum, copper, and steel, plastic films or sheets such as polyethylene terephthalate, coated paper, and rubber.

Further, a composite support, a support with rubber elasticity, a support with a rubber elastic layer, and a cylindrical support can also be used.

Primer layer> The primer layer used in the present invention needs to satisfy the following conditions. That is, it has good adhesion between the support and the photosensitive layer, is stable over time, is well-receptive to ink because the primer layer is exposed through exposure and development, and has good solvent resistance to developer solvents. That is.

If these conditions are met, 1. Examples include epoxy resins and polyurethane resins that are heat-cured using a suitable curing agent. Furthermore, a photocured layer made of a photodimerizable curable resin can also be used, but epoxy resin is particularly preferred.

Typical examples of epoxy resins used in the primer layer of the present invention are as follows.

(1) Reaction product between bisphenol A and epichlorohydrin (2) Reaction product between novolac resin and epichlorohydrin (3) Reaction product between bisphenol F and epichlorohydrin (4) Reaction product between tetrabromobisphenol A and epichlorohydrin (5) Cycloaliphatic epoxy resin (compound having a cyclohexene oxide group, tricyclodecene oxide group, or cyclopentene oxide group) (6) Glycidyl ester-based 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 with glycidylated hydantoin ring, and triglycidyl isocyanurate with triazine ring) Epoxy resins include: In addition to these, any known epoxy resin, that is, one having an average of at least one epoxy group per molecule, can be used, but particularly preferred are the bisphenol A-based epoxy resins shown in (1). be. The general formula is as follows, and there are various epoxy equivalents, but the epoxy equivalent is 180 to 40.
00 is preferred.

I〉= Tomomi Iゝ口='/ As curing agents for the above epoxy resin, aliphatic polyamines, aromatic polyamines, polyamidoamines, polymercaptans, acid anhydrides, and tertiary amines are effective, but among them, acid The most effective method is one using an anhydride as a curing agent and a tertiary amine as a curing accelerator.

The amount of acid anhydride curing agent added is 2 to 1 per epoxy resin.
00% by weight (hereinafter abbreviated as %). The particularly preferable range varies depending on the type of epoxy resin and acid anhydride used, but as an example, epoxy 50
When using an epoxy resin with a weight of 0 and an acid anhydride with an acid anhydride equivalent of 150, it is 10 to 50%.

The amount of the tertiary amine compound used as a curing accelerator is 0.5 to 30%, particularly preferably 5% to the epoxy resin.
It is in the range of ~20%.

The above-mentioned epoxy resin, acid anhydride, and tertiary amine compound are dissolved in a suitable organic solvent, coated on a support, and then cured by heating at a temperature of 80 to 150°C.

In this primer layer, if necessary, a filler such as titanium oxide, an antihalation agent, and a dye or acid generator for imparting printout properties may be appropriately mixed and used.

In the present invention, it is important that the thickness of the primer layer is 6μ to 100μ, preferably 8μ to 15μ. In other words, a thickness of less than 6 μm, which is the conventional thickness range, has no effect on scratch resistance. Further, when a metal plate finished through a normal rolling process is used as a support, a thicker film is advantageous in order to have a shielding effect against form defects and chemical adverse effects on the surface of the support.

On the other hand, if it is too thick, poor adhesion with the photosensitive layer will occur. The reason for this is not fully understood, but uncured substances and curing catalysts in the brimer layer collect at the interface between the primer layer and the photosensitive layer, forming a weak pandering layer. This is thought to be because it deteriorates the adhesion. Furthermore, if the film is thick, high temperature or long curing conditions are required to uniformly cure the entire primer layer, which is also economically disadvantageous.

Photosensitive layer> The photosensitive layer used in the present invention may be any layer as long as its solubility in a developer changes before and after exposure.

Compounds or compositions constituting such a photosensitive layer include the following.

(1) An unsaturated monomer or oligomer thereof with a boiling point of 100°C or higher and nonvolatile at room temperature, a photosensitizer, a thermal polymerization inhibitor, and if necessary, a filler to provide shape retention at room temperature and some A composition containing an additive.

Examples of unsaturated monomers include ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxyethyl(meth)acrylate,
A series of acrylic esters such as hydroxypropyl (meth)acrylate, glycidyl (meth)acrylate, 1-lyrolow-2-hydroxyethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, methacrylic esters, ethylenebisacrylamide , acrylamide derivatives such as N-methylol acrylamide and methoxymethyl acrylamide, esters of allyl alcohol such as triallyl cyanurate, triallyl phosphate, diallyl phthalate and diallyl maleate, other styrene derivatives, cinnamic acid derivatives, etc. I can do it.

Examples of photosensitizers include benzophenone derivatives, benzoin derivatives, anthraquinone derivatives, aldehydes, ketones,
Sulfur compounds, halogen compounds, or dyes such as methylene blue and 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 colloidal silica, calcium carbonate, magnesium carbonate, fine inorganic powders such as iron oxide, polyvinyl acetate, poly(meth)acrylic esters, polyethylene, polypropylene, polychloride with thousands of molecules. Examples include vinyl, vinyl polymers such as polyvinylidene chloride, resol phenol resins before curing, urea resins, melamine resins, epoxy resins, and unsaturated polyester resins.

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

Polymers whose main component is a photosensitive polymer such as chill, polyamide, or polycarbonate as a photosensitive group in the main chain or side chain (for example, U.S. Pat. No. 3.030.208
No. 3.707.373 and No. 3.453.2
Compounds such as those described in the specifications of No. 37); mainly composed of photosensitive polyesters derived from (2-properidene) malonic acid compounds such as cinnamylidene malonic acid and difunctional glycols (e.g. photopolymers such as those described in U.S. Pat. Nos. 2,956,878 and 3,173,787); polyvinyl alcohol, starch, cellulose and the like; Cinnamate esters of hydroxyl group-containing polymers such as U.S. Pat.
．． 372, No. 2, 732.301, etc.), as well as JP-A-58
The polymers described in Japanese Patent No. 25302 and No. 59-17550 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 salts of condensates of formaldehyde and diazo amines such as vara diazo diphenylamine, vara diazomonoethylaniline, and vara diazobenzylethylaniline.

The photocurable azide resin includes polyvinyl alcohol azidophthalic acid ester or azylbenzoic acid ester, styrene-maleic anhydride copolymer, and aromatic azide alcohol such as β-(4-azidophenol) ethanol. Examples include esters of

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

[4] A composition comprising an o-quinonediazide compound.

Particularly preferred 0-quinonediazide compounds are 0-naphthoquinonediazide compounds, such as U.S. Pat.
6, 118, 2.767, 092, 2.7
72,972, No. 2.859.112, No. 2.
No. 907.665, No. 3.046.110, No. 3
．． No. 046.111, No. 3.046.115, No. 3.046.118, No. 3.046.119, No. 3.046, 120, No. 3.046.121,
Same No. 3.046.122, Same No. 3.046.123, Same No. 3.061.430, Same No. 3.102゜809
No. 3.106.465, No. 3.635.70
Including the specifications of No. 9 and No. 3.647.443,
It is described in a large number of publications, and these can be suitably used. Among these, 0-naphthoquinonediazide sulfonic acid ester or 0-naphthoquinonediazidecarboxylic acid ester of aromatic hydroxy compounds,
and of aromatic amine compounds. - naphthoquinonediazide sulfonic acid amide or.

- naphthoquinone diazide carboxylic acid amide is preferred;
For example, benzoquinone-1,2-diazide sulfonic acid, ester of naphthoquinone-1,2-diazide sulfonic acid and polyhydroxyphenyl (hereinafter esters include partial esters), naphthoquinone-1,2-diazide-4
-Sulfonic acid or naphthoquinone-1,2-diazide-
Ester of 5-sulfonic acid and pyrogallol acetone resin, ester of benzoquinone-1,2-diazide sulfonic acid or naphthoquinone-1,2-diazide sulfonic acid and novolak type phenol formaldehyde resin or novolak type cresol formaldehyde resin, poly(
Amides of p-aminostyrene) and naphthoquinone-1,2-diazide-4-sulfonic acid or naphthoquinone-1,2-diazide-5-sulfonic acid, poly p-hydroxystyrene and naphthoquinone-1,2-diazide-4-sulfone Acids or esters of naphthoquinone-1,2-diazido-5-sulfonic acid, esters of polyethylene glycol and naphthoquinone-1,2-diazide-4-sulfonic acid or naphthoquinone-1,2-diazide-5-sulfonic acid, polymers Amine and naphthoquinone-1,2-diazide-4
-Sulfonic acid or naphthoquinone-1,2-diazide-
Amide of 5-sulfonic acid, polymethacrylic acid p-hydroxyanilide and naphthoquinone-1,2-diazide-4-
Sulfonic acid or naphthoquinone-1,2-diazide-5
- Esters of sulfonic acids, amine-modified natural resin rosins and amides of naphthoquinone-1,2-diazide-5-sulfonic acid, epoxy resins from bisphenol Δ and propylene oxide and naphthoquinone-1,2-diazide-5- Esters of sulfonic acids, polymers of monoesters of (meth)acrylic acid and dihydroxyphenyl and esters of naphthoquinone-1,2-diazido-4-sulfonic acid or naphthoquinone-1,2-diazido-5-sulfonic acid, aminoisophthalic acid Polymerized condensates of sialyl ester and naphthoquinone diazide sulfonic acid, polycarbonate and quinone diazide sulfonic acid esters or quinone diazides crosslinked with isocyanate, etc., bisphenol A and naphthoquinone-1,2-diazide-4-sulfone acid or ester of naphthoquinone-1,2-diazide-5-sulfonic acid, naphthoquinone-1
, 2-diazide-5-sulfonic acid and phenol, phenol such as p-cresol, ester of alcohol such as ethyl, propyl, butyl, amyl alcohol, naphthoquinone-1,2-diazide-5-sulfonic acid and aniline , acid amides with amines such as p-hydroxyaniline, and the like.

Among these, particularly preferred is the photodimerization type (2).

The thickness of the photosensitive layer as explained above is preferably as thin as possible as long as the photosensitive layer and silicone rubber layer in the image area can be removed in the development process after image exposure, but as a general guideline: 1 μ or less, especially 0.1 to 0
．． It is desirable and preferable that the thickness be selected from the range of 5μ.

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

Here, R is an alkyl group having 1 to 10 carbon atoms or a phenyl group, but preferably 60% or more of R is a methyl group. Such linear organic polysiloxanes are generally made into crosslinked silicone rubber by adding a reactive crosslinking agent. Crosslinking agents used in so-called room temperature (low temperature) curing silicone rubber include acetoxysilane, which may or may not have a monovalent organic group bonded to a silicon atom;
Silanes such as ketoximesilane, aminoxysilane, amidosilane, alkoxysilane, hydroxysilane,
There are siloxanes, organo-hydrodiene polysiloxanes, etc. which are condensates of these with a low degree of polymerization. In addition, in order to improve the adhesive strength of the photosensitive layer/silicone rubber layer and prevent the interlayer adhesive strength from decreasing even after a long period of time, reactive silane compounds having an allyl isocyanurate group, reactive silane compounds having an aminoalkyl group, etc. are used. It may also be added to silicone rubber compositions.

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

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

The thickness of the silicone rubber layer should be as thin as possible from the point of view of tone reproducibility, and a certain degree of thickness is required from the point of view of printing durability and printing smudges, so the appropriate thickness is usually about 0.5 to 10μ. Yes, 1.0 to 3.0μ is desirable.

The waterless PS plate of the present invention basically has the above-described structure, but if necessary, an adhesive layer can be interposed between the photosensitive layer and the silicone rubber layer. Various reactive crosslinking agents and silane coupling agents are used for such adhesive layers. Among them, effective ones include silane coupling agents containing oxime groups, reactive silicone compounds having aminoalkyl groups, reactive silane compounds having allyl isocyanurate groups, and organic titanate compounds (
titanium-based brimers), etc.

In principle, the thickness of the adhesive layer should be at least a monomolecular layer, but
For actual coating operations, a range of 10 mμ to 0.5 μm is selected. If it becomes too thick, it is not only economically disadvantageous;
It adversely affects the penetration of the developer into the photosensitive layer and deteriorates image reproducibility. - Furthermore, a protective film may be provided on the silicone rubber layer of the waterless PS plate of the present invention, if necessary.

Plate-making method> The waterless PS plate according to the present invention is exposed to light through a transparent original image, and then developed with a developer that dissolves the photosensitive layer in the non-image area and the silicone rubber layer thereon. is removed, forming a waterless plate.

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

As the developer, those known as those for waterless PS plates can be used. For example, aliphatic hydrocarbons such as bexane,
Heptane, “isopar E, H.

Add the following polar solvent to aromatic hydrocarbons (toluene, xylene, etc.) or halogenated hydrocarbons (triclene, etc.) It is preferable that

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 (ethyl acetate, methyl cellosolve acetate, cellosolve acetate, carpitol acetate, etc.) It is also possible to dye the image area at the same time as development by adding dyes such as crystal violet and acedrasin red to the developer.

Development can be carried out by a known method, such as rubbing with a developing pad containing a developer as described above, or pouring a developer onto the printing plate and then rubbing with a developing brush. As a result, the silicone rubber layer and photosensitive layer in the image area are removed, the surface of the primer layer is exposed, and that area becomes an ink receiving area.

〔Effect of the invention〕

In the waterless PS plate according to the present invention, by setting the thickness of the primer layer to 6 to 100 μm, even if the thickness of the photosensitive layer is reduced, it has excellent scratch resistance and abrasion resistance. Plates have the advantage of high printing durability.

Furthermore, the waterless PS plate according to the present invention is developed by dissolving the photosensitive layer in the image area with a developer and removing the silicone rubber layer thereon.
It has excellent developability.

Furthermore, since the waterless PS plate according to the present invention only needs to be provided with a thin photosensitive layer, the image area of the waterless plate prepared from this plate is not only the silicone rubber layer but also the concave portion from which the photosensitive layer is removed. Despite this, the depth is only substantially equivalent to the thickness of the silicone rubber layer, and the exposed primer layer has extremely high oil sensitivity. It has the advantage of being able to be plated thinly.

[Action of the invention]

In the present invention, the mechanism by which the scratch resistance is improved by using a thick primer layer has not been fully elucidated, but when the primer layer is thick, the primer layer is removed from the plate surface on the silicone rubber layer. This is thought to be because it absorbs the force received and recovers even if it is partially pushed. If the plate surface on the silicone rubber layer of a waterless PS plate, where the conventional primer layer is thin, is accidentally scratched with a metal piece or the like, the silicone rubber layer in that area is removed and becomes an ink receiving area, causing stains during printing. Waterless P where these plates were damaged and appeared as stains on the printed matter.
When the silicone rubber layer, photosensitive layer and primer layer of the S plate were removed and the support surface was observed under a microscope, deep concave scratches were found. On the other hand, for a waterless PS plate with a thick primer layer, when the silicone rubber layer, photosensitive layer and primer layer were removed in the same way from a plate surface scratched with a metal piece, etc., and the surface of the support was observed, it was found that He wasn't hurt at all.

Further, when the entire layer was observed, the silicone rubber layer remained with only a slight dent. This is thought to be because the thick resin layer of the primer layer functions as an elastic body, ie, a cushion layer, that recovers the partial force applied to the plate surface on the silicone rubber layer. On the other hand, if there is no brimer layer or if it is thin, the elastic resin layer is absent or thin, and it is thought that the surface of the metal support, which is susceptible to permanent strain, will be damaged.

Next, the present invention will be explained in more detail with reference to Examples.

〔Example〕

Example 1 The following brimer footwear composition was applied to a smooth aluminum plate degreased in a conventional manner to a dry film thickness of 10 μm, and cured by heating at 120° C. for 5 minutes.

Methyl cellosolve acetate 120 parts by weight Toluene
120 parts by weight of methyl ethyl ketone 120 parts by weight of ffi The cured primer layer is prepared using a developer or a mixed solvent for coating the photosensitive layer (mixture of methyl ethyl ketone/toluene-1 part by weight).
It did not dissolve even when immersed in water.

On the aluminum plate coated with the primer layer, the following photosensitive composition was applied to a dry film thickness of 0.25 μm and dried.

Dibutyltin dioctanoate 0.8 parts by weight Methyl ethyl ketone 450 parts by weight Toluene
450 parts by weight Next, the following silicone rubber composition was coated on the photosensitive layer to a dry film thickness of 2 μm, and dried and smoked to obtain a cured silicone rubber layer.

Dibutyltin dioctanoate 3.3-fold Isopar G
(manufactured by Esso Chemical Co., Ltd.) 1500 parts by weight A 12μ thick one-sided matted polypropylene film was laminated on the surface of the silicone rubber layer obtained as above, and waterless P was applied.
I got the S version.

A positive film was layered on this printing original plate, and the film was vacuum-adhered to the Nuark Co., Ltd. ET 26 V [IDN5 ULTRA-
After 30 counts of exposure using PLUSFLIP-TOP PLATB MAKBR, the laminate film was peeled off and 90 parts by weight of Isopar H (manufactured by Esso Chemical Co., Ltd.) was added.
When immersed in a developer consisting of 7 parts by weight of diethylene glycol monobutyl ether, 3 parts by weight of diethylene glycol monoethyl ether, 81 parts by weight of diethylene glycol monoethyl ether, and 5 parts by weight of diethyl succinate for 1 minute and lightly rubbed with a development pad, the unexposed areas of the photosensitive layer and silicone rubber layer were removed. removed. In this way, a waterless lithographic printing plate was obtained that faithfully reproduced the image of the positive film over the entire surface of the printing plate.

On the surface of the non-image area of this waterless lithographic printing plate, apply a continuous weight scratch strength tester TYPE-HBID manufactured by Shinto Kagaku Co., Ltd.
Wounds were made with ON-18 using a 0.4 mm diameter sapphire needle. The load was in the range of 10g to 500g.

This is a Heidelberg GTO with the dampening water supply system removed.
Attach it to the printing machine and use the Toyo Ink TOYOKING [
When printed with 1LTRA TKU Aquares G black ink, 10,000 clean prints were obtained.
The reproducibility of highlighted areas was also good. The plate surface whose non-image areas were scratched with a sapphire needle was only tingling and smudged at a load of 350 g or more.

Example 2 The following primer layer composition was applied to a smooth aluminum plate degreased in a conventional manner to a dry film thickness of 13 μm, and dried.

p-phenylene diacrylic acid varnish 100 parts by weight Photosensitive unsaturated polyester obtained by 1=1 polycondensation of chill and 1,4-dihydroxyethyloxycyclohexane 1-methyl-2-benzoylmethylate 6 parts by weight Ren-β
- Naphthothiazoline methyl cellosolve acetate 300 parts by weight toluene
Next, the aluminum plate coated with 150 parts by weight of the above composition was coated with Nuark's FT26V U.
DNSULTRA-PLUS FLIP-TOP P
LATB MA was exposed to light for 1000 counts by OR. The aluminum plate coated with the primer layer obtained in this way does not dissolve even if it is immersed in a developer or a mixed solvent for coating the photosensitive layer (a mixture of methyl cellosolve acedate/toluene-2-fluoride in a ratio of 1 part by weight). There wasn't. On the aluminum plate coated with the primer layer, the following photosensitive composition was applied to a dry film thickness of 0.25 μm and dried.

Methyl cellosolve acetate) 600 parts by weight, 11 parts by weight, toluene, 300 parts by weight.Next, the following silicone rubber composition was applied to the photosensitive layer to a dry film thickness of 2 parts.
．． It was applied to a thickness of 2 μm and dried to damage the silicone rubber cured layer.

Dibutyltin dioctanoate 2.0 parts by weight Isopar G (manufactured by Esso Chemical Co., Ltd.) 1200 parts by weight Example 1 was applied to the surface of the silicone rubber layer obtained as above.
A waterless PS plate was obtained by laminating a polypropylene film similar to the above.

When this waterless PS plate was imagewise exposed and developed in the same manner as in Example 1, the photosensitive layer and silicone rubber layer in the unexposed areas were quickly removed. Furthermore, in the same manner as in Example 1, when the plate surface in the non-printing area was scratched with a sapphire needle, the load was 40.
It was only slightly stained at areas weighing 0g or more. Highlight reproducibility was also good even in printing with low ink density.

Example 3 and Comparative Example 1 A primer layer consisting of the following composition was prepared so as to have a dry film thickness of 0.5 μ to 16 μ, as shown in Table 1. This composition was applied onto a smooth aluminum plate that had been degreased in a conventional manner and cured by heating at 120° C. for 5 minutes.

Methyl cellosolve acetate 120wt R toluene
Methyl ethyl ketone (highlighted part) 120 (highlighted part) On top of these coated and cured primer layers, a photosensitive layer and a silicone rubber layer similar to those in Example 1 were coated, and a polypropylene film similar to that in Example 1 was laminated. A PS version without water was obtained.

The printing plate precursor obtained in this way was prepared in the same manner as in Example 1.
When imagewise exposed, developed, and printed by scratching with a sapphire needle, the photosensitive layer and silicone rubber layer in the unexposed areas of each waterless lithographic printing plate were quickly removed. Further, in all printing plates, printed matter with good highlight reproducibility was obtained. However, as shown in Table 1, the scratch resistance varied depending on the thickness of the primer layer.

Table 1 From the results in Table 1, it can be seen that scratch resistance is good when the thickness of the primer layer is 6 μm or more.

It can be seen that when a primer with a thin film thickness is used as shown in the comparative example, the scratch resistance is insufficient.

[Brief explanation of drawings]

FIG. 1 is an enlarged sectional view of one embodiment of the waterless PS plate of the present invention, and FIG. 2 is an enlarged sectional view of a waterless plate made from this waterless PS plate. 1...Support 2...Primer layer 3...Photosensitive layer 4...Silicone rubber layer 4A...Image area 4B...Non-image area Fig. 1 4:S / Refoon Co. 7A4 2nd FI! J Procedural Amendments Director General of the Patent Office Mr. Michibu Uga 'A1, Indication of Case Patent Application No. 35755 of 1985
No. 2, Title of the invention Photosensitive lithographic printing plate that does not require dampening water 3, Person making the amendment Relationship to the case Applicant name (520) Fuji Photo Film Co., Ltd. 4, Agent 5, Date of amendment order Initiator 1, On page 11 of the specification, line 5, “as used” is changed to “
"The one I used," he corrected. 2. On page 35 of the circular, in lines 6 to 4 from the bottom, replace “120 parts by weight of methyl cellosolve acetate” with “mixed solvent (mixture of methyl cellosolve acenate/toluene/methyl ethyl ketone in a weight ratio of 1/1/1) 300 ~6.O
Corrected to ``O0 parts by weight''.

Claims (2)

[Claims] (1) A photosensitive lithographic printing plate that does not require dampening water and has a primer layer, a photosensitive layer, and a silicone rubber layer in this order on a support, characterized in that the thickness of the primer layer is 6 to 100 μm. Photosensitive planographic printing plate that does not require dampening water. (2) The dampening water-free photosensitive lithographic printing plate according to claim (1), wherein the photosensitive layer has a thickness of 1 μm or less.