JPH04235555A - Dampening water-free plate for planography - Google Patents

Abstract

PURPOSE:To obtain a dampening water-free photosensitive plate for planography which is excellent in stickiness to a primer layer even with the use of an aluminium plate support not subjected to activating treatment and hence excellent in printing resistance. CONSTITUTION:In a dampening water-free photosensitive plate for planography having at least a primer layer, a photosensitive layer and a silicon rubber layer stacked on a support in that order from the support side, the primer layer contains at least a polymer containing a tetrahydrofurfuryl group, an ethylene unsaturated monomer or oligomer and a photopolymerization initiator and is photochemically hardened before application of the photosensitive layer.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive lithographic printing plate that does not require dampening water, and more particularly to a photosensitive lithographic printing plate that does not require dampening water and has a photopolymerizable primer layer.

0002

[Prior Art] In recent years, attempts have been made to develop planographic printing plates that do not require dampening water. Water-free photosensitive lithographic printing plates are known.

[0003] In the photosensitive lithographic printing plate that does not require dampening water as described above, for example, Japanese Patent Publication No. 61-5
Thermosetting type epoxy resins described in publications such as No. 4219 and JP-A-62-194255, or JP-A-62-19425, etc.
A typical example is a photo-curing type that utilizes photo-crosslinking, etc., as described in Publication No. 229031.

0004

[Problems to be Solved by the Invention] In a photosensitive lithographic printing plate that does not require dampening water and uses a primer layer as described above,
Usually, when coating is performed using an aluminum plate as a support, the adhesion between the primer layer and the aluminum plate is insufficient, and for this reason, aluminum plates subjected to various activation treatments have been used in the past. Such poor adhesion occurs particularly when the printing plate is bent, resulting in a decrease in printing durability, so improvements in these have been desired.

[0005] Accordingly, an object of the present invention is to provide a novel photosensitive lithographic printing plate that does not require dampening water and eliminates the above-mentioned drawbacks. That is, an object of the present invention is to provide a photosensitive lithographic printing plate that does not require dampening water and has excellent adhesion to a primer layer even when an aluminum plate support is not subjected to activation treatment, and as a result, printing durability is improved. There is a particular thing.

[0006]

[Means for Solving the Problems] In view of the above-mentioned problems, the present inventors have conducted intensive research and found that the above-mentioned object of the present invention is to coat at least a primer layer, a photosensitive layer and a silicone rubber layer on a support from the support side. In the dampening water-free photosensitive lithographic printing plate, the primer layer comprises at least a)
A dampener comprising a tetrahydrofurfuryl group-containing polymer, b) an ethylenically unsaturated monomer or oligomer, and c) a photopolymerization initiator, and is photocured before coating a photosensitive layer. We have found that this can be accomplished by providing a water-free photosensitive lithographic printing plate.

The present invention will be explained in more detail below.

In the photosensitive lithographic printing plate that does not require dampening water of the present invention, the primer layer contains a) a tetrahydrofurfuryl group-containing polymer, b) an ethylenically unsaturated monomer or oligomer, and c) a photopolymerization initiator. There is.

In the present invention, tetrahydrofurfuryl (meth)acrylate is particularly preferably used as the tetrahydrofurfuryl group-containing polymer.

[0010] In the present invention, when an acrylic compound and a methacrylic compound are jointly referred to hereinafter, they will be written as "(meth)acrylic...".

The tetrahydrofurfuryl group-containing polymer may be a copolymer, and the copolymer monomers include (1) a monomer having an alcoholic hydroxyl group, such as 2
-Hydroxyethyl (meth)acrylate, N-(4-
Monomers such as hydroxyethylphenyl)methacrylamide and hydroxy-methyldiacetone(meth)acrylamide; (2) Monomers having an aromatic hydroxyl group, such as N-(4
-Hydroxyphenyl)(meth)acrylamide, o-
, m-, p-hydroxystyrene, o-, m-, p-hydroxyphenyl (meth)acrylate, (3) (meth)acrylic acid, α, β-unsaturated carboxylic acids such as maleic anhydride, (4) Methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (
meth)acrylate, amyl(meth)acrylate, hexyl(meth)acrylate, octyl(meth)acrylate, 2-chloroethyl acrylate, 2-hydroxyethyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, glycidyl(meth)acrylate acrylate, optionally substituted alkyl (meth)acrylate such as N-dimethylaminoethyl (meth)acrylate, (5) (meth)acrylamide, N-methylol (meth)acrylamide, N-ethylacrylamide, N-hexylmethacrylate Optionally substituted (meth)acrylamides such as amide, N-cyclohexylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, N-nitrophenylacrylamide, N-ethyl-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, etc. (7) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl benzoate, etc. (8) Styrenes such as styrene, α-methylstyrene, chloromethylstyrene, (9) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, phenyl vinyl ketone, (10) ethylene, propylene, Examples include olefins such as isobutylene, butadiene, and isoprene; (11) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, acrylonitrile, methacrylonitrile, and the like. In particular, compound (4) is preferably used.

The amount of the tetrahydrofurfuryl group-containing monomer in the tetrahydrofurfuryl group-containing polymer is not particularly limited, but is preferably 1 to 80% by weight, particularly preferably 2 to 50% by weight.

[0013] The tetrahydrofurfuryl group-containing polymer of the present invention was subjected to gel permeation chromatography (G
The weight average molecular weight measured by PC) method is 5,000.
~1,000,000 (in terms of styrene) is preferred. 5
If the value is lower than 1,000, it may be damaged by the coating solvent or developer of the photosensitive layer even after photocuring.
If the value is greater than 000, it is difficult to select a coating solvent.

The proportion of the tetrahydrofurfuryl group-containing polymer in the primer layer is usually 10 to 99% by weight, preferably 30 to 97% by weight.

Further, the ethylenically unsaturated monomer or oligomer used in the present invention has a boiling point of 1 at normal pressure.
It is a compound containing two or more terminal ethylene groups that can be polymerized at 00°C or higher, and various known compounds can be used. For example, unsaturated carboxylic acids, esters of unsaturated carboxylic acids and aliphatic polyhydroxy compounds, esters of unsaturated carboxylic acids and aromatic polyhydroxy compounds, unsaturated carboxylic acids and polyhydric carboxylic acids, and the aforementioned aliphatic polyhydroxy compounds. Examples include esters obtained by esterification reactions with polyhydric hydroxy compounds such as hydroxy compounds and aromatic polyhydroxy compounds.
For example, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate,
Examples include meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol triacrylate, hydroquinone di(meth)acrylate, pyrogallol triacrylate, 2,2'-bis(4-acryloxy-diethoxyphenyl)propane, and the like. Other examples include (meth)acrylamide, hexamethylenebis(meth)acrylamide, etc.
Examples include acrylamides, vinyl urethane compounds, and epoxy (meth)acrylates.

In the present invention, the amount of the ethylenically unsaturated monomer or oligomer in the primer layer is 10
~90% by weight, preferably 20-80% by weight.

[0017] As the photopolymerization initiator, conventionally known ones can be used, and for example, benzoin, benzoin alkyl ether, benzophenone, anthraquinone, benzyl, Michler's ketone, a complex system of hiimidazole and Michler's ketone, etc. are preferably used. I can do it.

The amount of the photopolymerization initiator in the primer layer is 0.1 to 20% by weight, preferably 0.2 to 10% by weight.

In the present invention, in addition to the above components, the primer layer may contain other fillers or antihalation agents, coloring agents such as dyes and pigments, coating improvers, plasticizers, stabilizers, and sensitizers, as required. It may also contain a curing agent or the like in an amount not exceeding 10% by weight. It is also possible to use various conventionally known polymers, such as polyamide and polyurethane, which are usually used in primer layers.

Examples of dyes that can be included in the primer layer include Victoria Pure Blue BOH, Oil Blue #603, Oil Pink #312, Patent Pure Blue, Crystal Violet, Leuco Crystal Violet, Brilliant Green, Ethyl Violet, and Methyl Green. , erythrosin B, basic fuchsin, malachite green, leucomalachite green, m-cresol purple, cresol red,
Xylenol Blue, Rhodamine B, Auramine, 4-
Triphenylmethane type, diphenylmethane type represented by p-diethylaminophenylimino naphthoquinone, cyano-p-diethylaminophenyl acetanilide, etc.
Oxazine type, xanthene type, iminonaphthoquinone type,
Examples include azomethine-based or anthraquinone-based dyes.

Examples of coating properties improvers include alkyl ethers (for example, ethyl cellulose, methyl cellulose), fluorine-based surfactants, and nonionic surfactants (for example, "Pluronic L-64" (manufactured by Asahi Denka), " FC-
430'' (manufactured by Sumitomo 3M).

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

Furthermore, 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-
Modified novolak resins such as butylphenol benzaldehyde resin and rosin-modified novolac resin, and o-naphthoquinonediazide sulfonic acid esters (esterification rate of OH group: 20 to 70 mol%) of these modified novolac resins can be added and used. can.

[0024] When the above primer composition contains a pigment, it is optionally dispersed in a suitable organic solvent by a known dispersion method (SGI, homogenizer, etc.) and then filtered. After coating the dispersion on a support and drying it,
The primer layer of the present invention is formed by photocuring.

For photocuring, a known light source such as a mercury lamp, a xenon lamp, or natural light is used, and an exposure amount sufficient to cure the primer layer (usually, for example, 50 mJ/cm2 to 5 J/c) is used.
This can be done by exposing to light within a range of m2.

Further, the above-mentioned curing is desirably carried out at least before the coating of the photosensitive layer is completed, and more preferably immediately after coating.

In the present invention, the thickness of the primer layer is 1
It is preferably from mg/dm2 to 500mg/dm2, more preferably from 3mg/dm2 to 300mg/dm
It is 2.

In the present invention, a photosensitive layer is provided on the primer layer, and 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. But it is possible.

Specifically, for example, a photo-solubilizable photosensitive layer containing an o-quinonediazide compound, an o-nitrobenzyl carbinol ester compound, etc., a photo-insolubilizable photosensitive layer containing a diazo compound, a compound having an addition-polymerizable vinyl group, etc. Examples include a photosensitive layer.

The above-mentioned o-quinonediazide compounds are compounds having at least one o-quinonediazide group, preferably an o-benzoquinonediazide group or an o-naphthoquinonediazide group, and include known compounds of various structures, such as J. Kosar, “Light Sensitive Systems” (John Wiley & Sams, Inc. 19)
This includes compounds described in detail on pages 339 to 353 (published in 1965). For example, various hydroxyl compounds and benzoquinone-1,2-diazide sulfonic acid,
Examples include esters with naphthoquinone-1,2-diazide sulfonic acid and the like. Examples of the hydroxyl compound used include condensation resins of phenols such as phenol, cresol and pyrogallol and carbonyl group-containing compounds such as formaldehyde, benzaldehyde and acetone, particularly resins obtained by condensation in the presence of an acidic catalyst.

As the photosensitive layer containing a diazo compound, a photosensitive layer containing as essential components a diazo resin and a (meth)acrylic ester or amide-containing polymer having a hydroxyl group is preferred, as disclosed in JP-A-1-104286.

In the case of such a photosensitive layer, the proportion of the diazo resin in the photosensitive layer is preferably 1 to 90% by weight, more preferably 3 to 60% by weight.

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, etc. and aliphatic polyhydroxy compounds, esters of unsaturated carboxylic acids and aromatic polyhydroxy compounds, unsaturated carboxylic acids and polyhydric carboxylic acids, and polyhydroxy compounds such as the aforementioned aliphatic polyhydroxy compounds and aromatic polyhydroxy compounds. Examples include esters obtained by an esterification reaction with a hydroxyl compound, and are specifically described in JP-A-59-71048 and the like.

In the present invention, all of the photosensitive layers listed above can be used, but a photosensitive layer containing a diazo resin is preferred from the viewpoint of adhesion to the primer layer.

Furthermore, in the present invention, in addition to the above-mentioned materials, dyes, pigments, known exposure visible image agents, coating property improvers, etc. may be added to the photosensitive layer to form a developed visible image. It is possible to improve the properties, exposure and visible image properties, and coating properties.

Further, in the present invention, it is preferable that the photosensitive layer contains a hydroxyl group-containing polymer. As such a hydroxyl group-containing polymer, an alcoholic hydroxyl group-containing poly(meth)acrylic acid ester or amide is preferably used.

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

Monomers copolymerizable with the above hydroxyl group-containing monomers include (1) monomers having an aromatic hydroxyl group, such as N-(4
-hydroxyphenyl)acrylamide, N-(4-hydroxyphenyl)methacrylamide, o-, m-, p
-Hydroxystyrene, o-, m-, p-hydroxyphenyl acrylate or -methacrylate (2) α,β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic anhydride, etc. (3) Methyl acrylate, acrylic 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
) (Substituted) alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, cyclohexyl methacrylate, 2-hydroxyethyl methacrylate, 4-hydroxybutyl methacrylate, glycidyl methacrylate, N-dimethylaminoethyl methacrylate, (5 ) Acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N-ethylacrylamide, N-hexylmethacrylamide, N-cyclohexylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, N-nitrophenylacrylamide, Acrylamides or methacrylamides such as N-ethyl-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 esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl benzoate, etc. (8) Styrenes such as styrene, α-methylstyrene, methylstyrene, chloromethylstyrene, (9) Methyl vinyl ketone, ethyl Vinyl ketones such as vinyl ketone, propyl vinyl ketone, phenyl vinyl ketone, (10) olefins such as ethylene, propylene, isobutylene, butadiene, isoprene, (11) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, Examples include acrylonitrile, methacrylonitrile, and the like. In particular, each of the compounds (1) to (4) is preferred.

[0039] The amount of the hydroxyl group-containing monomer in the hydroxyl group-containing polymer is not particularly limited, but is preferably 5 to 5.
It is 100% by weight, particularly preferably 20-100% by weight.

The weight average molecular weight of the hydroxyl group-containing polymer of the present invention measured by GPC method is 5,000 to 1,000,000 (
styrene equivalent) is preferred.

The proportion of the hydroxyl group-containing polymer in the photosensitive layer is usually 10 to 99% by weight, preferably 40 to 9% by weight.
It is 7% by weight.

The thickness of the photosensitive layer is 0.1 mg/dm2 to 30
mg/dm2 is preferred, 0.5mg/dm2 to 10m
g/dm2 is more preferred.

In the present invention, a silicone rubber layer is further provided on the photosensitive layer, and the silicone rubber used in the silicone rubber layer is preferably linear or crosslinked organopolysiloxane. The organopolysiloxane usually has a molecular weight of 1,000 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.

[0044] 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 above organopolysiloxane has a repeating unit represented by the following formula 1 in its main chain.

[0046]

[Formula 1] In the formula, R1 and R2 are alkyl, aryl, alkenyl, or a combination thereof, each of which may have a substituent such as a cyano group, a halogen atom, or a hydroxyl group; A fluoropropyl group is preferred, and a methyl group is particularly preferred.

[0047] As the silicone crosslinking agent, the following formula 2 is used.
So-called acetic acid-removed type, oxime-eliminated type, alcohol-eliminated type, deaminated type, dehydrated type, etc., which have a group represented by -OH (in the formula, R and R' are alkyl groups). Examples include condensed silicone crosslinking agents.

[0048]

embedded image Examples of such crosslinking agents include tetraacetoxysilane, methyltriacetoxysilane, ethyltriacetoxysilane, phenyltriacetoxysilane, dimethyldiacetoxysilane, diethyldiacetoxysilane, vinyltriacetoxysilane, and methyltriacetoxysilane. methoxysilane,
Dimethyldimethoxysilane, vinyltrimethoxysilane, methyltris(acetoneoxime)silane, methyltris(N-methyl,N-acetylamino)silane, vinyltri(methylethylketoxime)silane, methyltri(methylethylketoxime)silane or its oligomer, isocyanurate group Examples include reactive silane compounds that have

The amount of each of these crosslinking agents is preferably in the range of 0.5 to 30 parts by weight per 100 parts by weight of the organopolysiloxane.

Examples of the condensation catalyst include dibutyltin dilaurate, dibutyltin acetate, dibutyltin maleate, and the like.

The addition type refers to one in which a hydrogen group in a crosslinking agent is added to an unsaturated group in the main body, such as a vinyl group (-CH=CH2), resulting in crosslinking. 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.

[0052] For the silicone rubber layer in the present invention, either or both of condensation type silicone rubber and addition type silicone rubber can be used. It is also possible to use condensed and addition type organopolysiloxanes having hydroxyl groups, unsaturated groups, etc. in one organopolysiloxane.

[0053] Among the commercially available silicone rubbers according to the present invention, a preferred example is "
KS-705F”, “KE-41”, “KE-42”,
"KE-44", Toshiba Silicone (manufactured by) "YE5505"
”, “YF3057”, Toray Silicone Co., Ltd. “SH-
Condensation type silicone rubber such as "781", "PRX-305", "SH-237" and "KS-837" manufactured by Shin-Etsu Co., Ltd.
”, “KE-103”, “KE-106”, “KE-1
300”, Toshiba Silicone (manufactured by) “TSE-3032”
, "RTU-B", Toray Silicone (manufactured by) "SH-95"
Examples include addition-type silicone rubber such as "55".

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, such fillers preferably have an average particle diameter of 500 nm 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.
On the contrary, a certain degree of thickness is required from the viewpoint of printing stains, etc., so generally, 3 mg/dm2 to 50 mg/dm2 is preferable, and 5 mg/dm2 to 30 mg/dm2 is more preferable.

Furthermore, the photosensitive lithographic printing plate that does not require dampening water of the present invention may have a protective layer provided on the silicone rubber layer, and a method for providing the protective layer is the polypropylene film described in Japanese Patent Publication No. 61-614. There are known methods such as laminating or applying a high molecular weight polymer as described in JP-A No. 61-27545.

[0057] The substrate used in the present invention is as follows:
Any material can be used as long as it has the flexibility to be set in a normal lithographic printing machine and can withstand the load applied during printing, and there are no particular restrictions on the layer structure. Examples include papers such as coated paper, metal plates such as aluminum plates, and plastic films such as polyethylene terephthalate.
An aluminum plate or a composite material of aluminum foil and other materials is preferable, and from the viewpoint of printing durability, an aluminum plate is particularly preferable.

In 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, resulting in a primer layer. It is exposed as an image area, and a lithographic printing plate that does not require dampening water is formed.

In this case, it is preferable to dye the image area with a dye during or after development. For such dyeing, a dyeing solution containing water as a main component and a dye as an essential component is used. Preferred dyes include specifically the following acidic dyes and basic dyes.

Acidic dyes include nitro dyes, such as naphthol yellow (C.I. Acid Yellow 1).
, monoazo dyes such as Fast Red A (C.I.
．． Acid Red 88), disazo dyes such as Naphthol Blue Black (C.I. Acid Black 1), nitroso dyes such as Naphthol Green B (
C. I. Acid Green 1), triphenylmethane dyes such as Patent Blue (C.I. Acid Blue 3), Brilliant Milling Green B (C.I.
I. Acid Green 9), xanthene dyes such as Sulfo-Rhodamina B (C.I. Acid Red 52);
), anthraquinone dyes such as Alizarin Direct Blue A2G (C.I. Acid Blue 40),
Azine dyes, such as Woolfast Blue GL (C
．． I. Acid Blue 102), quinoline dyes, such as Quinoline Yellow (C.I. Acid Yellow 3);
), etc., and preferable basic dyes include, specifically, the following.

Diphenylmethane dyes such as auramine O (C.I. Basic Yellow 2), triphenylmethane dyes such as magenta (C.I. Basic Violet 14), methyl violet (C.I. Basic Violet 1) ), malachite green (
C. I. Basic Green 4), thiazole dye,
For example, Thioflavin T (C.I. Basic Yellow 1), xanthene dyes, such as Rhodamine B (C.I.
Basic Violet 10), oxazine dyes such as Neil Blue BX (C.I. Basic Blue 12), thiazine dyes such as Methylene Blue B (C.I.
．． I. Basic Blue 9), azine dyes such as Safranin T (C.I. Basic Red 2), azo dyes such as Bismarck Brown G (C.I. Basic Brown 1), indocyanine dyes such as Astraflaxin FF (C.I. Basic Red 12)
etc. In the present invention, triphenylmethane dyes are particularly preferably used. These dyes are used in aqueous solutions, and their concentrations are preferably between 0.1 g/liter and 10 g/liter.

[0062] In the present invention, when dyeing is performed using these dye aqueous solutions, the concentration thereof is 10°C to 50°C. The dyeing method is carried out by immersing the developed printing plate in a dyeing solution, or by applying or shower-sprinkling an aqueous dye solution onto the printing plate. A dyeing aid can be added to this aqueous dye solution as required.

[0063] As the dyeing aid, water-soluble organic solvents, surfactants, etc. are used to facilitate dyeing of the primer layer.

As the organic solvent, ethanol, solfit, benzyl alcohol, etc. are preferably used, and as the surfactant, nonionic surfactants are preferred from the viewpoint of foaming properties.

The light source used for exposure is 180n
Any general-purpose light source including ultraviolet rays and visible rays with a wavelength of more than m may be used, but carbon arc lamps, mercury lamps, xenon lamps, metal halide lamps, strobes, etc. are particularly preferred.

The developer used in the development process includes water, the following polar solvents, alkaline compounds such as amines, surfactants, aliphatic hydrocarbons (hexane, heptane, "Isoper E.H.G." Aromatic hydrocarbons (toluene, xylene, etc.) or halogenated hydrocarbons (triclene, etc.) are added as necessary. .

Polar solvent alcohols (methanol, ethanol, β-anilinoethanol, propylene glycol, 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, methyl cellosolve acetate, cellosolve acetate, carbitol acetate, etc.) Development can be done by rubbing with a developer pad containing a developer like the one mentioned above, or by pouring the developer onto the plate surface and then using a developer brush. This can be done by various known methods such as rubbing.

[0068]

【Example】

EXAMPLES The present invention will be explained in more detail below with reference to Examples, but the present invention is not limited to these Examples.

(Synthesis of Diazo Resin-1) 14.5 g of p-diazodiphenylamine sulfate was dissolved in 40.9 g of concentrated sulfuric acid under ice cooling. 1.0 g of paraformaldehyde was slowly added dropwise to this reaction solution so that the reaction temperature did not exceed 10°C. Thereafter, stirring was continued for 2 hours under ice cooling. This reaction mixture was added dropwise to 500 ml of ethanol under ice cooling, and the resulting precipitate was filtered. After washing with ethanol, this precipitate was dissolved in 100 ml of pure water, and to this solution was added a cold concentrated aqueous solution in which 6.8 g of zinc chloride was dissolved. 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.

[0070] The coupling product with β-naphthol is GP
The diazo resin had a weight average molecular weight (Mw) of 1,500 and a number average molecular weight of 500 in terms of styrene, as measured by method C.

(Preparation of photosensitive lithographic printing plate sample that does not require dampening water) The following primer layer composition was applied to a degreased aluminum plate with a thickness of 0.24 mm at 60°C using a whirler.
The primer layer was applied by drying at 100° C. for 2 minutes. The dry film thickness was 130 mg/dm2. The primer layer composition was dispersed using a high-pressure bulb homogenizer. (Primer layer composition) (1) Binder resin (listed in Table 1) 10
0 parts (2) DPCA-60 (manufactured by Nippon Kayaku Co., Ltd.)
60 copies

[0072]

[Chemical formula 3]

[0073]

[Chemical formula 4] (5) KET-YELLOW402 (yellow pigment manufactured by Dainippon Ink Co., Ltd.) 8 parts (6) Zinc oxide (average particle size: 0.12μ)
After applying 20 parts and drying, apply Unicure (Ushio Inc.)
Exposure was carried out at -160 W and 4 m/min.

Next, the following photosensitive composition was coated on the primer layer and dried at 80° C. for 2 minutes to a thickness of 0.3 μm.
A photosensitive layer was formed. (Photosensitive composition) (1) Diazo resin-1
100 parts (2) Copolymer resin of 2-hydroxyethyl methacrylate, N-(4-hydroxyphenylmethacrylamide, methacrylic acid in a molar ratio of 40/55/5 (Mw = 4.2 x 104)
100 copies (3) Orange IV
Part 8 (4) Methyl lactate
900 parts of the following silicone rubber composition was then applied onto the photosensitive layer to a thickness of 2.0 g/m2,
It was dried at 90°C for 10 minutes. (Silicone rubber layer composition) (1) Dimethylpolysiloxane having hydroxyl groups at both ends (molecular weight 52,000)
100 copies

[0075]

[Chemical formula 5] (3) Dibutyltin dilaurate
0.8 parts (4) Isopar E (manufactured by Esso Chemical) 900 parts Next, a 6μ thick polypropylene film was laminated on the silicone rubber layer to obtain a photosensitive lithographic printing plate sample 1-5 that did not require dampening water. Ta.

After vacuum-adhering a positive film to the top surface of each of the above samples, it was exposed to light at 400 mJ/cm2 using a metal halide lamp as a light source, and then the following developer was added to
Standard development was performed by immersion for 1 minute. Next, the surface of the plate material was rubbed with a pad impregnated with a developer to remove the unexposed silicone rubber layer and the photosensitive layer, and then a dyeing solution of the following composition was applied to a cloth and the plate was lightly rubbed. A printing plate was obtained by washing with water. (Developer) Potassium silicate
9 parts potassium hydroxide
4 parts propylene glycol 5 parts water

82 parts (staining solution) Solfit (solvent manufactured by Clarei Soprene Chemical Co., Ltd.) 20
Part Rheodol TW-0120 (surfactant manufactured by Kao Corporation) 0.
5 parts benzyl alcohol
5.0 part Victoria Pure Blue BOH
1.0 part water
A continuous load type scratch strength tester Type-HEIDON- manufactured by Shinto Kagaku Co., Ltd. was applied to the non-printing area of each of the 100 copies obtained.
Heidel GTO (manufactured by Heidel) with the dampening water supply device removed after making scratches using a sapphire needle with a diameter of 0.2 mm according to No. 18 at varying loads between 10 g and 80 g.
Aquares Five TP manufactured by Toyo Ink Manufacturing Co., Ltd.
Printing was performed using M ink. At this time, the load appearing as an image on the printed matter is shown in Table 2 as "HEIDON scratching load". The higher this value is, the better the scratch strength is. In addition, the number of printed sheets at which stains appear on the printed matter is defined as the printing durability, and is shown in Table 2.

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[Table 1]

[0078]

[Table 2] As is clear from Tables 1 and 2, Samples 1-4 of the present invention having the structure of the present invention are different from Comparative Sample 5 using a primer layer containing no tetrahydrofurfuryl group-containing polymer.
It can be seen that the scratch strength and printing durability are excellent compared to the above.

[0079]

Effects of the Invention As explained in detail above, the present invention provides excellent adhesion to the primer layer even when using an aluminum plate support that is not subjected to activation treatment, resulting in excellent printing durability and no need for dampening water. A photosensitive lithographic printing plate can be provided.

Claims (1)

[Claims] 1. A dampening water-free photosensitive lithographic printing plate comprising at least a primer layer, a photosensitive layer, and a silicone rubber layer in this order from the support side on a support, wherein the primer layer contains at least a) a tetrahydrofurfuryl group. dampening water-free photosensitive lithographic printing, characterized in that it contains a polymer, b) an ethylenically unsaturated monomer or oligomer, and c) a photopolymerization initiator, and is photocured before coating the photosensitive layer. Edition.