JPH10246952A - Waterless original ligthographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a negative waterless original lithographic printing plate of a photosensitive-layer-remaining type, good in image reproducibility and superior in storage stability. SOLUTION: This waterless original lighographic printing plate is provided with a primer layer, a photosensitive layer, and a silicone rubber layer in this order on a base plate and this photosensitive layer contains an cetone-pyrogallol resin having a cross-linking structure, and the silicone rubber layer is hardened by the addition reaction of vinyl groups and SiH groups.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lithographic printing plate precursor without water, and more particularly, to a lithographic printing plate precursor having good image reproducibility and excellent storage stability.

[0002]

2. Description of the Related Art Conventionally, various printing plates have been proposed for performing lithographic printing using silicone rubber or fluororesin as an ink repellent layer without using dampening water.

As photosensitive lithographic printing plates using a fluororesin for the ink repellent layer, there are JP-A-2-254449 and JP-A-2-85855, and the like.
H, 1H, 2H, 2H-heptadecafluorodecyl acrylate and 1H, 1H, 2H, 2H-heptadecafluorodecyl methacrylate are used.

A positive type photosensitive lithographic printing plate having a silicone rubber as an ink repellent layer is disclosed in, for example, JP-B-54-26.
No. 923, Japanese Patent Publication No. 56-23150, etc., a waterless planographic printing plate in which a photopolymerizable adhesive layer and a silicone rubber layer are laminated on a substrate;
No. 5, JP-B-3-56622 and the like, and a waterless planographic printing plate in which a photodimerizing photosensitive layer and a silicone rubber layer are laminated on a substrate.

A negative type photosensitive lithographic printing plate using silicone rubber for the ink repellent layer is disclosed in Japanese Patent Publication No. 61-6 / 1986.
No. 16, JP-B-61-54218, etc. propose a waterless planographic printing plate having a photosensitive layer containing a quinonediazide compound on a support and a silicone rubber layer provided on the photosensitive layer via an adhesive layer.

Various inventions have also been made on methods for improving the UV ink resistance and solvent resistance of a printing plate after the printing plate is manufactured. For example, JP-B-61-617, JP-A-57-192965, and JP-A-57-192957.
JP-A-57-205740, JP-A-60-133
452 and JP-A-60-169852.

[0007] Of these, Japanese Patent Application Laid-Open No. Sho 60-169852
In Japanese Patent Laid-Open Publication No. H11-264, a waterless lithographic plate having a photosensitive layer using a compound obtained by adding a quinonediazide group to an acetone pyrogallol resin is proposed. However, in this method, the developability is unstable because the acetone pyrogallol resin is not crosslinked in the raw plate state, and it is necessary to perform image exposure and overall exposure after development in order to improve the solvent resistance of the photosensitive layer. Therefore, the workability was poor and the effect of improving the solvent resistance was not satisfactory. Further, in this method, a so-called solution-developing waterless lithographic plate in which the photosensitive layer is dissolved by development, there is a problem in that the ink deposition property and the ink mileage are inferior.

In Japanese Patent Application Laid-Open Nos. 60-133453 and 60-35735, waterless lithographic plates using a compound obtained by adding a quinonediazide group to an acetone pyrogallol resin have been proposed. The waterless lithographic plate has poor ink deposition and ink mileage, and requires heat treatment to improve the solvent resistance of the unexposed areas after development, resulting in poor workability and low effect of improving solvent resistance. It was not a target.

As a method for solving these problems, for example, Japanese Patent Publication No. 61-54222 discloses a method in which 1,2 is coated on a support.
Negative having a photo-peelable photosensitive layer in which a partially esterified product of naphthoquinone-2-diazide-5-sulfonic acid chloride and phenol formaldehyde hydronovolak resin is cross-linked with a polyfunctional isocyanate, and the photosensitive layer in the image area remains during development. Lithographic printing plates without mold water have been proposed. By this method, not only the solvent resistance during development but also the UV
Ink resistance and solvent resistance were also improved.

However, since these waterless lithographic plates have a small number of hydroxyl groups in the photosensitive component, the reaction with the isocyanate is slow, and it is necessary to use an excess of isocyanate in order to obtain a solvent resistance that can withstand practical use. For this reason, there is a problem that the isocyanate which has not been reacted at the initial stage promotes the crosslinking of the photosensitive layer with time, and the sensitivity is lowered.

On the other hand, regarding the silicone rubber layer used as the ink repellent layer of the waterless planographic printing plate precursor, a condensation type silicone rubber has conventionally been generally used. There was a problem that it was difficult to control the speed and the adhesion to the photosensitive layer.

As a method for solving these problems, various methods using an addition type silicone rubber have been proposed. Japanese Patent Application Laid-Open No. 4-68353 proposes a positive waterless planographic printing plate precursor in which an additional silicone rubber layer containing a hydrogensiloxane having a specific structure is coated on a photopolymerizable photosensitive layer. However, there was a problem that the adhesiveness with the photopolymerizable photosensitive layer was insufficient, and the curability of the silicone rubber layer was not sufficient, and it took time to cure. Therefore, Japanese Patent Application Laid-Open Nos.
No. 94007 proposes a method for improving the curability of a silicone rubber layer by using a photopolymerizable monomer having a specific structure as a photopolymerizable monomer in a photosensitive layer. JP-A-4-17
No. 4437 proposes a method of using a photopolymerizable monomer having 6 to 60 ethylene oxide groups or propylene oxide groups in one molecule. However, although the curability of the silicone rubber layer is improved, the photosensitive layer is improved. Is not sufficient and has not been put to practical use.

Further, JP-A-6-202313 discloses an addition type containing a tertiary amine-based organosilicon compound having a hydrolyzable group as an adhesion promoter on a photopolymerizable, photocrosslinkable or photoremovable photosensitive layer. A method of applying a silicone rubber layer has been proposed. Although the adhesiveness with the photosensitive layer can be improved by this method, the adhesiveness changes depending on the humidity at the time of coating the silicone rubber layer, and it is difficult to obtain stable adhesiveness. There is a problem that ink resilience decreases.

Japanese Unexamined Patent Publication (Kokai) No. 6-202313 discloses a waterless planographic printing plate precursor in which the photosensitive layer contains an acetone pyrogallol resin having a quinonediazide group and the silicone rubber layer uses an addition type silicone rubber.
Since the photosensitive layer is not cross-linked, the curability of the silicone rubber layer is insufficient, and the solvent resistance of the non-image area is insufficient, as in the case of the above, and the ink adhesion and ink mileage are poor. Has not been reached.

[0015]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a waterless planographic printing plate precursor having good image reproducibility and excellent storage stability.

[0016]

As a result of repeated studies, the present inventors have found that the above-mentioned problems can be solved by the following method.

That is, the objects of the present invention are as follows: (1) In a waterless lithographic printing plate precursor comprising at least a primer layer, a photosensitive layer and a silicone rubber layer laminated on a substrate in this order, the photosensitive layer forms a crosslinked structure. A waterless planographic printing plate precursor comprising an acetone pyrogallol resin having a quinonediazide group and a silicone rubber layer cured by an addition reaction between a vinyl group and a SiH group.

(2) The waterless planographic printing plate precursor as described in (1), wherein the acetone pyrogallol resin is represented by the following general formula 1.

[0019]

Embedded image (Wherein X, Y, and Z each independently represent a hydroxyl group or a sulfonic ester group of quinonediazide; n is 5
Represents an integer of from 12 to 12. (3) An organopolysiloxane in which the silicone rubber layer has two or more vinyl groups in the molecule and three or more Si atoms in the molecule
The lithographic printing plate precursor according to (1) or (2), further comprising a hydrogen siloxane having an H group and a platinum compound.

(4) The value of the number of SiH groups / molecular weight in the molecule of the hydrogen siloxane is 0.001 mol /
g of the lithographic printing plate precursor without water according to (1) to (3).

(5) The number of vinyl groups in the silicone rubber layer is 1
The waterless planographic printing plate precursor as described in any one of (1) to (4), wherein the ratio of the number of SiH groups to the lithographic printing plate is from 1.5 to 15.

(6) When the acetone pyrogallol resin is 1,2
-Naphthoquinone-2-diazide-5-sulfonic acid chloride or 1,2-naphthoquinone-2-diazide-4
It is esterified with sulfonic acid chloride and has a degree of esterification of 5 to 67% (1)
Waterless planographic printing plate precursors according to (5).

(7) The waterless planographic printing plate precursor as described in any one of (1) to (6), wherein the acetone pyrogallol resin is crosslinked with an isocyanate compound.

(8) The isocyanate content in the photosensitive layer is 5 to 45% by weight based on the acetone pyrogallol resin having a quinonediazide group.
Waterless planographic printing plate precursors according to (7).

Is achieved by:

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

First, the photosensitive layer used in the present invention will be described.

The photosensitive layer of the present invention needs to contain an acetone pyrogallol resin having a quinonediazide group and the acetone pyrogallol resin has to form a crosslinked structure.

First, the acetone pyrogallol resin will be described. The acetone pyrogallol resin referred to in the present invention refers to a resin obtained by polymerizing acetone and pyrogallol in the presence of a catalyst such as phosphorous oxychloride, and has a structure as represented by the general formula (1). As the acetone pyrogallol resin used in the present invention, those in which n in the general formula (1) is in the range of 5 to 12 are preferable.
When n is less than 5, a large amount of a crosslinking agent is required to crosslink the photosensitive layer, and as a result, storage stability is adversely affected. Since it is difficult, it is expensive and not preferable.

The acetone pyrogallol resin used in the present invention must have a quinonediazide group in the molecule. As a method of adding a quinonediazide group to the acetone pyrogallol resin, a method of esterification with benzoquinonediazidesulfonic acid, naphthoquinonediazidesulfonic acid or the like is preferable.

Specifically, 1,2-benzoquinone-2-
Diazido-4-sulfonic acid chloride, 1,2-benzoquinone-2-diazide-4-sulfonic acid, 1,2-naphthoquinone-2-diazide-4-sulfonic acid chloride, 1,
2-naphthoquinone-2-diazide-4-sulfonic acid,
1,2-naphthoquinone-2-diazide-5-sulfonic acid chloride, 1,2-naphthoquinone-2-diazide-5
Sulfonic acid, 1,2-naphthoquinone-2-diazide-6
-Sulfonic acid chloride, 1,2-naphthoquinone-2-diazide-6-sulfonic acid, and the like, but the present invention is not limited thereto.

Among these compounds, 1,2-naphthoquinone-2-diazide-4-sulfonic acid chloride and
1,2-Naphthoquinone-2-diazide-5-sulfonic acid chloride is particularly effective.

The addition amount of the quinonediazide compound is as follows:
The esterification rate is preferably 5 to 67%, more preferably 15 to 60%, and still more preferably 30 to 50%.
Is preferred. The esterification ratio is a ratio of the number of hydroxyl groups esterified with the quinonediazide compound to the number of hydroxyl groups of the acetone pyrogallol resin expressed as a percentage. If the esterification ratio is less than 5%, the photosensitive components tend to decrease, and the image reproducibility tends to decrease. This is not preferred. If the esterification ratio is greater than 67%, the residual hydroxyl groups of the acetone pyrogallol resin decrease, A crosslinking reaction becomes difficult, and as a result, storage stability tends to decrease, which is not preferable.

In the photosensitive layer of the present invention, the above-mentioned acetone pyrogallol resin having a quinonediazide group needs to form a crosslinked structure. As a method of forming such a crosslinked structure, there is a method of adding a polyfunctional isocyanate or a polyfunctional epoxy compound shown below and thermally crosslinking the compound.

Examples of the polyfunctional isocyanates include paraphenylene diisocyanate, 2,4- or 2,6-toluylene diisocyanate (TDI), 4,4-diphenylmethane diisocyanate (MDI), tolidine diisocyanate (TODI), xylylene diisocyanate ( XDI), hydrogenated xylylene diisocyanate, cyclohexane diisocyanate, meta-xylylene diisocyanate (MXDI), hexamethylene diisocyanate (HDI or HMDI), lysine diisocyanate (LDI) (also known as 2,6-diisocyanatomethylcaproate), hydrogenated MDI (H12MDI) (also known as 4,4'-methylenebis (cyclohexyl isocyanate)), hydrogenated TDI (HTDI) (also known as methylcyclohexane 2,4 (2 , 6) diisocyanate), hydrogenated XDI (H6XDI) (also known as 1,3- (isocyanatomethyl) cyclohexane), isophorone diisocyanate (IPDI), diphenyl ether isocyanate,
Trimethylhexamethylene diisocyanate (IPD
I), diphenyl ether isocyanate, trimethylhexamethylene diisocyanate (TMDI), tetramethyl xylylene diisocyanate, polymethylene polyphenyl isocyanate, dimer acid diisocyanate (DDI), triphenylmethane triisocyanate,
Tris (isocyanatephenyl) thiophosphate, tetramethylxylylene diisocyanate, lysine ester triisocyanate, 1,6,11-undecane triisocyanate, 1,8-diisocyanate-4
-Isocyanate methyl octane, 1,3,6-hexamethylene triisocyanate, bicycloheptane triisocyanate and the like, polyhydric alcohol adducts of polyisocyanates, and polymers of polyisocyanates.

Examples of the polyfunctional epoxy compound include compounds obtained by reacting a hydroxyl group-containing compound with epihalohydrin.

Specific examples of the polyfunctional hydroxyl group-containing compound include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, 1,3-
Butanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-
Nonanediol, 1,10-decanediol, 2-butene-1,4-diol, 5-hexene-1,2-diol, 7-octene-1,2-diol, 3-mercapto-1,2-propanediol , Hydroquinone, dihydroxyanthraquinone, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, bisphenol A, bisphenol S, phenol formaldehyde novolak resin, resole resin, resorcinbenzaldehyde resin, pyrogallol acetone resin, hydroxystyrene polymers and copolymers, glycerin , Diglycerin, trimethylolpropane, 1,2,4-butanetriol, pentaerythritol, dipentaerythritol, sorbitol, sorbitan, polyvinyla Call, cellulose and its derivatives, polymers and copolymers of hydroxyethyl (meth) acrylate, and the like.

Of these, polyfunctional isocyanate compounds are preferred.

The amount of these polyfunctional compounds used is determined based on the amount of acetone pyrogallol resin having quinonediazide groups.
The amount is preferably 1 to 80 parts by weight, more preferably 2 to 50 parts by weight, even more preferably 2 to 20 parts by weight with respect to 0 parts by weight.
Parts by weight are preferred.

These thermal cross-linking reactions must be carried out at a temperature at which the photosensitivity of the quinonediazide group is not lost, usually at 150 ° C. or lower. For this purpose, it is preferable to use a catalyst in combination.

The acetone pyrogallol resin used in the present invention has about twice the number of hydroxyl groups per the same molecular weight as compared to the phenol formaldehyde novolak resin used in the conventional photosensitive layer cross-linked lithographic plate without water. It is considered that the number of residual hydroxyl groups after the addition of the quinonediazide group to be reacted with the crosslinking agent such as isocyanate increases, and the crosslinking reaction in the initial stage is likely to proceed. Therefore, as a result, the unreacted crosslinking agent can be reduced, so that the storage stability is considered to be improved.

Further, the photosensitive layer of the present invention preferably contains a binder polymer having a shape maintaining function. As such a binder polymer, any one which is soluble in an organic solvent and has a film forming ability can be used. Specific examples of the binder polymer include the following, but the present invention is not particularly limited to these examples.

(1) Vinyl polymers (a) Polyolefins Specific examples include poly (1-butene), poly (5-cyclohexyl-1-pentene), poly (1-decene), and poly (1,1-dichloroethylene). , Poly (1,1-dimethylbutane), poly (1,1-dimethylpropane), poly (1-dodecene), polyethylene, poly (1-heptene), poly (1-hexene), polymethylene, poly (6
-Methyl-1-heptene), poly (5-methyl-1-hexene), poly (2-methylpropane), poly (1-nomene), poly (1-octene), poly (1-pentene), poly (1-pentene) 5-phenyl-1-pentene), polypropylene, polyisobutylene, poly (1-butene), poly (vinyl butyl ether), poly (vinyl ethyl ether), poly (vinyl isobutyl ether), poly (vinyl methyl ether) and the like. Can be

(B) Polystyrenes A specific example is poly (4-[(2-butoxyethoxy)
Methyl] styrene), poly (4-decylstyrene), poly (4-dodecylstyrene), poly [4- (2-ethoxyethoxymethyl) styrene], poly [4- (hexoxymethyl) styrene], poly (4-hexyl) Styrene), poly (4-nonylstyrene), poly [4- (octoxymethyl) styrene], poly (4-octylstyrene), poly (4-tetradecylstyrene) and the like.

(C) Acrylic acid ester polymer and methacrylic acid ester polymer Specific examples include poly (butyl acrylate) and poly (s
ec-butyl acrylate), poly (tert-butyl acrylate), poly [2- (2-cyanoethylthio)
Ethyl acrylate], poly [3- (2-cyanoethylthio) propyl acrylate], poly [2- (cyanomethylthio) ethyl acrylate], poly [6- (cyanomethylthio) hexyl acrylate], poly [2- (3
-Cyanopropylthio) ethyl acrylate], poly (2-ethoxyethyl acrylate), poly (3-ethoxypropyl acrylate), poly (ethyl acrylate), poly (2-ethylbutyl acrylate), poly (2-ethylhexyl acrylate), Poly (5-ethyl-2-nonyl acrylate), poly (2-ethylthioethyl acrylate), poly (3-ethylthiopropyl acrylate), poly (heptyl acrylate), poly (2-heptyl acrylate), poly (hexyl acrylate) ), Poly (isobutyl acrylate), poly (isopropyl acrylate), poly (2-methoxyethyl acrylate), poly (3-methoxypropyl acrylate), poly (2-methylbutyl acrylate), poly (3-methylbutyl acrylate) Relate), poly (2-methyl-7-ethyl-4-undecyl acrylate), and the like.

(2) Unvulcanized rubber Natural rubber, (NR), a homopolymer or a copolymer selected from butadiene, isoprene, styrene, acrylonitrile, acrylates and methacrylates, such as polybutadiene ( BR), styrene-butadiene copolymer (SBR), carboxy-modified styrene-
Butadiene copolymer, polyisoprene (NR), polyisobutylene, polychloroprene (CR), polyneoprene, acrylate-butadiene copolymer, methacrylate-butadiene copolymer, acrylate-acrylonitrile copolymer ( ANM), isobutylene-isoprene copolymer (IIR), acrylonitrile-butadiene copolymer (NBR), carboxy-modified acrylonitrile-butadiene copolymer, acrylonitrile-chloroprene copolymer, acrylonitrile-isoprene copolymer, ethylene-propylene copolymer Polymer (EP
M, EPDM), vinyl pyridine-styrene-butadiene copolymer, styrene-isoprene copolymer and the like.

(3) Polyoxides (polyethers) Trioxane, ethylene oxide, propylene oxide, 2,3-epoxybutane, 3,4-epoxybutene, 2,3-epoxypentane, 1,2-epoxyhexane, epoxycyclohexane , Epoxycycloheptane, epoxycyclooctane, styrene oxide, 2-
Phenyl-1,2-epoxypropane, tetramethylethylene oxide, and the like.

(4) Polyesters Polyesters obtained by polycondensation of polyhydric alcohols and polycarboxylic acids as shown below, polyesters obtained by polymerization of polyhydric alcohols and polycarboxylic anhydrides, and ring opening of lactones Examples include polyester obtained by polymerization and the like, and polyester obtained from a mixture of these polyhydric alcohols, polycarboxylic acids, polycarboxylic anhydrides, and lactones.

Specific examples of polyhydric alcohols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butylene glycol, 1,5-pentanediol, and 1,6-pentanediol. Hexanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, triethylene glycol, p-xylene glycol, hydrogenated bisphenol A, bisphenol hydroxypropyl ether,
Glycerin, trimethylolethane, trimethylolpropane, trishydroxymethylaminomethane, pentaerythritol, dipentaerythritol, sorbitol and the like can be mentioned.

Specific examples of polycarboxylic acids and polycarboxylic anhydrides include phthalic anhydride, isophthalic acid, terephthalic acid, succinic anhydride, adipic acid, azelaic acid,
Sebacic acid, Tetrahydrophthalic anhydride, Hexahydrophthalic anhydride, Tetrabromophthalic anhydride, Tetrachlorophthalic anhydride, Hetic anhydride, Hymic anhydride, Maleic anhydride, Fumaric acid, Itaconic acid, Trimellitic anhydride, Methylcyclohexentricarboxylic acid Anhydride, pyromellitic anhydride and the like can be mentioned.

Examples of the lactone include β-propiolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone and the like.

(5) Polyurethanes Polyurethanes of 1,4-butanediol with hexamethylene diisocyanate, toluene diisocyanate, naphthalene-1,5-diisocyanate and the like can be mentioned.

(6) Polyamides Copolymers of the following monomers may be mentioned. ε-caprolactam, ω-laurolactam, ω-aminoundecanoic acid, hexamethylenediamine, 4,4-bis-aminocyclohexylmethane, 2,4,4-trimethylhexamethylenediamine, isophoronediamine, glycols, isophthalic acid, adipine Acids, sebacic acid, dodecanoic acid and the like.

These polymers that can be used as the binder polymer may be used alone, or a mixture of several kinds of polymers may be used.

Among these binder polymers, polyurethane, polyester, vinyl polymer and unvulcanized rubber are preferred.

The use amount of the binder polymer is preferably from 15 to 80% by weight, more preferably from 1 to 80% by weight, based on the components of the photosensitive layer.
5 to 75% by weight. 15% by weight of binder polymer
When the amount is less than 80%, it is difficult to develop satisfactory photosensitive properties. On the other hand, when the amount is more than 80% by weight, the amount of quinonediazide groups is reduced, which deteriorates image reproducibility and developability.

In addition to the above components, it is optional to add additives such as acids, dyes, pigments, photochromic agents and catalysts to the photosensitive layer composition, if necessary.

Preferred compositions of the water-free lithographic photosensitive layer of the present invention include the following.

(1) 5 to 100 parts by weight of an acetone pyrogallol resin having a quinonediazide group (2) 5 to 50 parts by weight of a polyfunctional compound (3) 30 to 95 parts by weight of a binder polymer having shape retention 30 to 95 parts by weight The thickness is preferably 0.5 to 3 g / m ² in terms of dry weight, and 1.0 to 5 g / m ^{2 in} terms of workability during production.
Is more preferred. If the thickness of the photosensitive layer is less than 0.5 g / m ^2, pinholes and the like are likely to occur, which is not preferable in view of coatability. On the other hand, if it exceeds 5 g / m ² , it is disadvantageous from an economic point of view and is not preferred.

Next, the waterless planographic substrate used in the present invention will be described. The waterless lithographic printing plate of the present invention must be flexible enough to be set in a normal printing press and withstand the load applied during printing. Accordingly, typical substrates include coated paper, metal plates such as aluminum, plastic films such as polyethylene terephthalate, rubber, and composites thereof. The surface of these substrates can be further coated with a primer layer or the like for the purpose of preventing halation and for other purposes.

The primer layer is obtained, for example, by curing various photosensitive polymers proposed in Japanese Patent Application Laid-Open No. Sho 60-22903 before exposing the photosensitive layers to each other. A methacrylic phosphorus-containing monomer proposed in Japanese Patent Application Laid-Open No. H07-15095 cured by exposing it before laminating a photosensitive layer, and a methacrylic epoxy compound proposed in JP-A-2-7049 before laminating a photosensitive layer. Exposed and cured, JP-A-62-5
No. 0760, epoxy resin cured by heat, gelatin disclosed in JP-A-63-133151, hardened gelatin, JP-A-1-2
No. 82270 and Japanese Patent Application Laid-Open No. 2-21072 using a urethane resin. In addition, a casein cured case is also effective.

For the purpose of further softening the primer layer, the primer layer has a glass transition temperature of room temperature or less, such as polyurethane, polyamide, styrene / butadiene rubber, carboxy-modified styrene / butadiene rubber, acrylonitrile / butadiene rubber, carboxy-modified acrylonitrile / Polymers such as butadiene rubber, polyisoprene rubber, acrylate rubber, polyethylene, chlorinated polyethylene and chlorinated polypropylene may be added.
The addition ratio is arbitrary, and the primer layer may be formed only with the additives as long as the film layer can be formed.

For the purpose of improving plate inspection, a dye, a pH indicator, an exposure baking agent, a photochromic compound, a photopolymerization initiator, and an adhesion auxiliary agent such as a polymerizable monomer, a diazo resin, a silane Additives such as coupling agents, titanate coupling agents, aluminum coupling agents, zirconia coupling agents, and boron coupling agents), white pigments, and silica particles.

The thickness of the primer layer used in the present invention is preferably in the range of 0.1 to 20 g / m ^{2 on} a dry weight basis.
The range of from 10 to 10 g / m ² is more preferable.

Next, the addition type silicone rubber layer used in the present invention will be described. The addition type silicone rubber layer that can be used in the present invention has a thickness of 0.5 to 50 g / m ² , preferably 0.5 to 10 g / m ² , and has transparency through which ultraviolet rays can pass.

Such an addition type silicone rubber layer comprises an organopolysiloxane having at least two vinyl groups in a molecule and at least three SiHs in a molecule.
A solution obtained by diluting a hydrogen siloxane having a group and a platinum compound with an appropriate solvent is coated on the photosensitive layer,
It is formed by heating, drying and curing.

Examples of the organopolysiloxane having at least two vinyl groups in the molecule used in the silicone rubber layer of the present invention include those having a vinyl group at either the molecular chain terminal or in the middle, and an alkenyl group. Preferred as the organic group other than the above are a substituted or unsubstituted alkyl group and an aryl group. Further, it may contain a trace amount of hydroxyl group.

Specific examples of the organopolysiloxane having two or more vinyl groups in the molecule include the following, but the present invention is not limited thereto.

Polydimethylsiloxane having vinyl groups at both terminals, (methylvinylsiloxane) (dimethylsiloxane) copolymer having methyl groups at both terminals, (methylvinylsiloxane) (dimethylsiloxane) copolymer having vinyl groups at both terminals, A compound in which two or more molecules of a vinyl group polydimethylsiloxane are cross-linked by dimethylene, a (methyl 1-hexene siloxane) (dimethyl siloxane) copolymer having a methyl group at both terminals, and a (methyl 1-
Hexene siloxane) (dimethyl siloxane) copolymer and the like.

The organopolysiloxane having two or more vinyl groups in the molecule preferably has a molecular weight of 5,000 or more, more preferably 10,000 or more, in view of rubber properties after curing.

Further, these organopolysiloxanes having two or more vinyl groups in the molecule can be used alone, or a plurality of kinds thereof can be used by mixing at an arbitrary ratio.

The hydrogen siloxane having at least three or more SiH groups in the molecule includes a molecular chain terminal,
A compound having a SiH group at any one of the intermediates,
Preferred as the organic group other than the iH group are a substituted or unsubstituted alkyl group and an aryl group.

Specific examples of the hydrogen siloxane having at least three or more SiH groups in the molecule include the following, but the present invention is not limited thereto.

Polydimethylsiloxane having SiH groups at both terminals, polymethylhydrogensiloxane having methyl groups at both terminals, (methylhydrogensiloxane) (dimethylsiloxane) copolymer having methyl groups at both terminals, SiH at both terminals
(Methyl hydrogen siloxane) (dimethyl siloxane) copolymer, cyclic polymethyl hydrogen siloxane and the like.

Among these, those which can be preferably used in the present invention include at least three or more SiHs in the molecule.
The value obtained by dividing the number of SiH groups in the hydrogen siloxane having a group by the molecular weight is preferably 0.001 mol / g or more, more preferably 0.002 mol / g or more. If the amount is less than 0.001 mol / g, the curing rate is undesirably reduced.

These hydrogen siloxanes having three or more SiH groups in the molecule can be used alone, or two or more kinds can be used as a mixture at an arbitrary ratio.

The organic groups of the organopolysiloxane having two or more vinyl groups in the molecule and the hydrogensiloxane having three or more SiH groups in the molecule generally account for at least 60% of the number of groups in terms of improving ink repellency. Is preferably a methyl group.

When the organopolysiloxane having two or more vinyl groups in the molecule and the hydrogensiloxane having three or more SiH groups in the molecule are mixed and used, the ratio of the vinyl in the silicone rubber composition is as follows. When the number of groups is 1, the mixing ratio is preferably such that the number of SiH groups is 1.5 to 15, and more preferably 1.5 to 12.

When the number of SiH groups to the number of vinyl groups is 1.5
If it is less than 1, the curability of the silicone rubber layer decreases, and
If it is larger than 5, the silicone rubber becomes brittle and the wear resistance is undesirably reduced.

The platinum compound preferably used in the silicone rubber layer of the present invention is arbitrarily selected from known compounds, and includes platinum alone, platinum chloride, chloroplatinic acid, olefin-coordinated platinum and the like. Among these, olefin-coordinated platinum is preferable.

For the purpose of controlling the curing rate of the addition type silicone rubber composition, tetracyclo (methyl vinyl)
Vinyl group-containing organopolysiloxane such as siloxane, alcohol containing carbon-carbon triple bond, acetone,
It is preferable to add a reaction inhibitor such as methyl ethyl ketone, methanol, ethanol, and propylene glycol monomethyl ether.

The following are typical examples of the addition-type silicone rubber composition preferably used in the present invention.

(1) 100 parts by weight of organopolysiloxane having 2 or more vinyl groups in the molecule (2) 0.1 to 10000 parts by weight of hydrogen siloxane having 3 or more SiH groups in the molecule (3) Platinum compound 0.00001 to 10 parts by weight (4) Reaction inhibitor 0.1 to 10 parts by weight (5) Solvent 100 to 4000 parts by weight In addition to these compositions, a known adhesion promoter such as alkenyl trialkoxysilane is added. Or addition of a hydroxyl group-containing organopolysiloxane or a hydrolyzable functional group-containing silane (or siloxane), which is a composition of the condensation type silicone rubber layer, and silica for the purpose of improving rubber strength. It is also optional to add a known filler such as.

In the waterless lithographic printing plate described herein, it is optional to further coat various silicone rubber layers on the silicone rubber layer, and the adhesive force between the photosensitive resin layer and the silicone rubber layer can be reduced. It is optional to provide an adhesive layer between the photosensitive resin layer and the silicone rubber layer for the purpose of raising or for preventing poisoning of the catalyst in the silicone rubber composition.

The silicone rubber layer forming the surface layer of the waterless planographic printing plate precursor thus configured has problems that it is easily scratched during handling and that the negative film is hard to adhere in vacuum during the exposure step. It is preferable to attach a transparent protective film on the silicone rubber layer. The protective film is useful in the exposure step, but needs to be removed by peeling or dissolving in the development step.

The protective film has a UV-transmitting property, and
Those having a thickness of 0 μm or less, preferably 10 μm or less are preferred. Specific examples of the protective film include polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyethylene terephthalate, cellophane, and the like. These films may be provided with a mat in order to improve the vacuum adhesion in the printing frame during image exposure.

Further, a protective layer may be formed by coating a polymer which can be dissolved and removed instead of the protective film.

Next, a method for producing a waterless planographic printing plate precursor according to the present invention will be described. The primer layer composition is applied to the substrate using a normal coater such as a slit die coater, a reverse roll coater, an air knife coater, or a Meyer bar coater, or a rotary coater such as a wheyer, if necessary, and coated at 100 to 300 ° C. After curing at a temperature of several minutes, a coating solution for a photosensitive layer composition is applied,
After drying at a temperature of 0 ° C. for several minutes and heat curing as required, a silicone rubber layer composition is coated thereon,
Heat-treated at a temperature of 150 ° C. for several minutes to cure the rubber and form. Thereafter, a protective film is laminated as necessary.

It is preferable that the entire surface of the waterless planographic printing plate of the present invention is exposed to weak light before the image exposure in order to enhance the adhesion between the photosensitive layer and the silicone rubber layer. As the light source used for the overall exposure, a light source usually used for image exposure of a printing plate can be used. Specifically, there are a mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, a tungsten lamp, a fluorescent lamp and the like.

In the overall exposure, it is necessary that the photoreactive functional group of the quinonediazide compound, that is, the quinonediazide group is not completely reacted (deactivated) by the treatment.

The waterless planographic printing plate precursor of the present invention thus produced is exposed to actinic rays through a vacuum-contacted negative film. As a light source used in this exposure step, a high-pressure mercury lamp, a carbon arc lamp, a xenon lamp, a fluorescent lamp or the like can be usually used.

The exposed printing plate is peeled off the protective film, immersed in a developing solution, and developed using a developing pad or a developing brush. At this time, the silicone rubber layer at the exposed portion is peeled off and the photosensitive layer is exposed. As the developer used in the present invention, those known as developers for lithographic printing plates without water can be used. For example, aliphatic hydrocarbons (hexane, heptane, "Isoper E, H, G" (trade names of aliphatic hydrocarbons manufactured by Esso Chemical Co., Ltd.) or gasoline, kerosene, etc.), aromatic hydrocarbons (toluene,
Xylene), or a halogenated hydrocarbon (such as tricrene) to which the following polar solvent is added, or the polar solvent itself is preferable.

(1) alcohols methanol, ethanol, propanol, benzyl alcohol, ethylene glycol monophenyl ether,
-Methoxyethanol, 2-ethoxyethanol, carbitol monoethyl ether, carbitol monomethyl ether, triethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, polypropylene glycol monomethyl ether, polypropylene Glycol, triethylene glycol, tetraethylene glycol and the like.

(2) Ketones Examples include acetone and methyl ethyl ketone.

(3) Esters Ethyl acetate, methyl lactate, ethyl lactate, butyl lactate, propylene glycol monomethyl ether acetate, carbitol acetate, dibutyl phthalate, diethyl phthalate and the like can be mentioned.

(4) Others Examples include triethyl phosphate and tricresyl phosphate.

Further, water is added to the above-mentioned organic solvent-based developer, and the above-mentioned organic solvent is solubilized in water using a surfactant or the like. Further, an alkali agent such as sodium carbonate, monoethanolamine is further added thereon. An inorganic alkaline agent such as diethanolamine, triethanolamine, sodium silicate, potassium silicate, sodium hydroxide, potassium hydroxide, sodium borate, or mono, di, or triethanolamine, mono, di, or triethylamine; Mono, diisopropylamine, n-butylamine,
Organic amine compounds such as mono-, di-, or triisopropanolamine, ethyleneimine, and ethylenediimine can also be used.

Further, known basic dyes such as crystal violet, Victoria Pure Blue, and Astrazone Red, acid dyes, and oil-soluble dyes can be added to a developing solution to simultaneously develop and dye the image area.

However, the most preferable method for developing the waterless planographic printing plate precursor according to the present invention is disclosed in Japanese Patent Publication No. 4-386.
No. 5 and Japanese Patent Publication No. 4-29053 are preferable to process the exposed plate with a pretreatment liquid containing a basic compound and then develop with water or a developer containing water as a main component.

When developing the waterless planographic printing plate used in the present invention, the plate surface is pretreated with the above-mentioned developer using an automatic developing machine such as that commercially available from Toray Industries, Inc. After that, the developing can be suitably performed by rubbing the rotating brush plate surface while showering with tap water or the like. A specific example of the developing machine is TWL-1 manufactured by Toray Industries, Inc.
160, TWL-860, TWL-650, TWL-4
00, or JP-A-4-2265 or JP-A-5-265.
2272 and JP-A-5-6000. When an automatic developing machine is used, NP-1 (Toray Industries, Inc.)
Pretreatment liquid for lithographic negative mold without water production), NA as post-treatment liquid
It is preferable to use -1 (a post-treatment liquid for a waterless planographic negative mold manufactured by Toray Industries, Inc.). Also, instead of the above-mentioned developing machine,
Development can also be performed by spraying hot water or steam onto the plate surface.

[0101]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

Synthesis Example 1 50 g of pyrogallol was dissolved in 350 g of acetone, and 5 g of phosphorus oxychloride was added with stirring. After being left overnight at room temperature, the mixture was dropped into water while stirring to obtain a tar-like resin. After dissolving this resin again in acetone, it was poured into a large amount of water to obtain a solid. The solid was dried under vacuum to obtain the desired acetone pyrogallol resin.

The molecular weight of the obtained acetone pyrogallol resin was measured by using GPC and found to be Mw = 1300.

Next, 50 g of the above-mentioned acetone pyrogallol resin was used.
(About 0.04 mol) and 83 g (about 0.31 mol) of 1,2-naphthoquinone-2-diazide-5-sulfonic acid chloride were dissolved in 500 g of 1,4-dioxane. Next, 80 g of a 10% by weight aqueous solution of sodium carbonate was added dropwise over 20 minutes, and the mixture was stirred and reacted for 4 hours while maintaining the solution temperature at 40 ° C. After completion of the reaction, the solution was put into 1000 g of water to precipitate and sediment the product. The supernatant was removed and the residue was dried under reduced pressure to obtain acetone pyrogallol resin-1 having a quinonediazide group.

Synthesis Example 2 50 g of the acetone pyrogallol resin obtained in Synthesis Example 1
(About 0.04 mol) and 25 g (about 0.09 mol) of 1,2-naphthoquinone-2-diazide-4-sulfonic acid chloride were dissolved in 500 g of 1,4-dioxane. Next, 50 g of a 10% by weight aqueous solution of sodium carbonate was added dropwise over 20 minutes, and the mixture was stirred and reacted for 4 hours while maintaining the solution temperature at 40 ° C. After completion of the reaction, the solution was put into 1000 g of water to precipitate and sediment the product. The supernatant was removed and the residue was dried under reduced pressure to obtain acetone pyrogallol resin-2 having a quinonediazide group.

Synthesis Example 3 50 g of the acetone pyrogallol resin obtained in Synthesis Example 1
(About 0.04 mol) and 166 g (about 0.62 mol) of 1,2-naphthoquinone-2-diazide-5-sulfonic acid chloride were dissolved in 500 g of 1,4-dioxane. Next, 100 g of a 10% by weight aqueous solution of sodium carbonate was added dropwise over 20 minutes, and the mixture was stirred and reacted for 4 hours while maintaining the solution temperature at 40 ° C. After completion of the reaction, the solution was put into 1000 g of water to precipitate and sediment the product. The supernatant was removed and the residue was dried under reduced pressure to obtain acetone pyrogallol resin-3 having a quinonediazide group.

Synthesis Example 4 50 g of the acetone pyrogallol resin obtained in Synthesis Example 1
(About 0.04 mol) and 7.5 g (about 0.03 mol) of 1,2-naphthoquinone-2-diazide-5-sulfonic acid chloride were dissolved in 500 g of 1,4-dioxane. Next, 20 g of a 10% by weight aqueous solution of sodium carbonate was added dropwise over 20 minutes, and the mixture was stirred and reacted for 4 hours while maintaining the solution temperature at 40 ° C. After completion of the reaction, the solution was put into 1000 g of water to precipitate and sediment the product. The supernatant was removed and the residue was dried under reduced pressure to obtain an acetone pyrogallol resin-4 having a quinonediazide group.

Synthesis Example 5 50 g of the acetone pyrogallol resin obtained in Synthesis Example 1
(About 0.04 mol) and 174 g (about 0.65 mol) of 1,2-naphthoquinone-2-diazide-5-sulfonic acid chloride were dissolved in 500 g of 1,4-dioxane. Next, 100 g of a 10% by weight aqueous solution of sodium carbonate was added dropwise over 20 minutes, and the mixture was stirred and reacted for 4 hours while maintaining the solution temperature at 40 ° C. After completion of the reaction, the solution was put into 1000 g of water to precipitate and sediment the product. The supernatant was removed and the residue was dried under reduced pressure to obtain an acetone pyrogallol resin-5 having a quinonediazide group.

Example 1 The following primer composition was applied to a 0.24 mm-thick aluminum plate (manufactured by Sumitomo Metal Co., Ltd.) degreased by an ordinary method, followed by heat treatment at 200 ° C. for 2 minutes to 5 g / m 2. ² primer layers were applied.

<Solid Component: Coating Concentration 12%> (1) Polyurethane resin “SAMPLEN LQ-SZ18” (manufactured by Sanyo Chemical Industries, Ltd.) 75 parts by weight (2) Blocked isocyanate “Takenate B830” (Takeda Pharmaceutical Co., Ltd.) 15 parts by weight (3) Epoxy / urea resin 10 parts by weight <Solvent component> (4) Dimethylformamide Subsequently, a photosensitive layer composition having the following composition was added on top of this.
After drying at 20 ° C. for 30 seconds, a photosensitive layer of 1.2 g / m ² was provided.

<Solid Component: Coating Concentration 10%> (1) 70 parts by weight of an acetone pyrogallol resin having a quinonediazide group obtained in Synthesis Example 1 (degree of esterification: 33%) (2) 4,4′-diphenylmethane diisocyanate 21 Parts by weight (3) 30 parts by weight of a polyurethane resin "SAMPLEN LQ-T1331" (manufactured by Sanyo Chemical Industries, Ltd.) (4) 0.2 parts by weight of dibutyltin diacetate (5) 0.8 parts by weight of P-toluenesulfonic acid <Solvent Component> (6) Tetrahydrofuran Subsequently, a silicone rubber layer having the following composition was applied on the photosensitive layer with a bar coater, and the silicone rubber layer was applied by heat drying.

The following composition was applied with a bar coater as an addition reaction crosslinkable silicone rubber layer, and heat-cured at 130 ° C. for 1 minute to apply a 2 g / m ² silicone rubber layer.

<Solid component: 10%> (1) 100 parts by weight of α, ω-divinyl polydimethylsiloxane (degree of polymerization 770) (2) HMS-501 (manufactured by Chisso Corp., both ends methyl (methyl hydrogen siloxane)) (Dimethylsiloxane) copolymer SiH groups / molecular weight = 0.69 mol / g) 4 parts by weight (3) Olefin-coordinated platinum 0.02 parts by weight (4) Reaction inhibitor 0.3 parts by weight <Solvent component> ( 5) "Isopar" E (manufactured by Esso Chemical Co., Ltd.) In the above silicone rubber layer composition, the number of SiH groups per one vinyl group was about 7.9.

The laminated board obtained as described above was
A biaxially-stretched biaxially-stretched polypropylene film having a thickness of μm was laminated using a calender roller so that the non-matted surface was in contact with the silicone rubber layer, to obtain a negative type waterless planographic printing plate precursor.

Using a metal halide lamp (Idolfin 2000, manufactured by Iwasaki Electric Co., Ltd.), the printing plate was subjected to a UV meter (a light measure type UV, manufactured by Oak Manufacturing Co., Ltd.).
At -402 A), the entire surface was exposed at an illuminance of 11 mW / cm ² for 6 seconds.

The printing plate obtained as described above is
A positive film having 1-99% halftone dots in lines / inch and a gray scale (G / S) having an optical density difference of 0.15 steps were vacuum-adhered for 30 seconds using the above metal halide lamp. Thereafter, the laminate film was exposed from a distance of 1 m for 60 seconds to peel off the laminate film.

Thereafter, an automatic developing machine (TWL manufactured by Toray Industries, Inc .: TWL)
-1160) in a NP-1 pretreatment liquid at a liquid temperature of 45 ° C. (manufactured by Toray Industries, Inc .: a pretreatment liquid for an automatic developing machine) for 1 minute, and in pure water at a liquid temperature of 25 ° C. The silicone rubber layer in the exposed area was peeled off and removed with a developing brush, and the photosensitive layer in the image area was dyed with an NA-1 post-treatment liquid (manufactured by Toray Industries, Inc .: post-treatment liquid for an automatic developing machine) to form a printing plate. The gray scale sensitivity at that time was evaluated.

The gray scale sensitivity means the number of gray scale densities at which the silicone rubber layer was not removed after development, and the higher the result, the higher the sensitivity.

Further, the unexposed waterless lithographic plate was stored for 10 days in a 50 ° C., 70% RH atmosphere, and after storage, the same image reproducibility was evaluated as described above. The difference between the gray scale sensitivities before and after storage was evaluated as an index of storage stability.

Examples 2 to 3 In Example 2, the acetone pyrogallol resin having a quinonediazide group used in Example 1 was replaced with the acetone pyrogallol resin having a quinonediazide group obtained in Synthesis Example 2 (esterification degree: 10%). In Example 3, a waterless lithographic plate was produced in the same manner as in Example 1 except that the quinonediazide group-containing acetone pyrogallol resin (esterification degree: 66%) obtained in Synthesis Example 3 was used. Were evaluated for image reproducibility and storage stability.

Example 4 A negative waterless planographic printing plate precursor was prepared in the same manner as in Example 1 except that the composition of the photosensitive layer used in Example 1 was changed to the following composition, and evaluated in the same manner as in Example 1. Was done.

Photosensitive Layer Composition <Solid Component: Coating Concentration 10%> (1) Acetone pyrogallol resin having a quinonediazide group obtained in Synthesis Example 1 (degree of esterification 33%) 70 parts by weight (2) 4,4′- 5.3 parts by weight of diphenylmethane diisocyanate (3) 30 parts by weight of polyurethane resin "SAMPLEN LQ-T1331" (manufactured by Sanyo Chemical Industries, Ltd.) (4) 0.2 parts by weight of dibutyltin diacetate (5) P-toluenesulfonic acid 0.8 parts by weight <Solvent component> (6) Tetrahydrofuran Example 5 A negative waterless planographic printing plate precursor was prepared in the same manner as in Example 1 except that the composition of the photosensitive layer used in Example 1 was changed to the following composition. It was fabricated and evaluated in the same manner as in Example 1.

Photosensitive Layer Composition <Solid Component: Coating Concentration 10%> (1) Acetone pyrogallol resin having a quinonediazide group obtained in Synthesis Example 1 (degree of esterification: 33%) 70 parts by weight (2) 4,4′- 55 parts by weight of diphenylmethane diisocyanate (3) 30 parts by weight of polyurethane resin "Samprene LQ-T1331" (manufactured by Sanyo Chemical Industries, Ltd.) (4) 0.2 parts by weight of dibutyltin diacetate (5) P-toluenesulfonic acid 8 parts by weight <solvent component> (6) Tetrahydrofuran Example 6 A negative waterless planographic printing plate precursor was prepared in the same manner as in Example 1 except that the composition of the silicone rubber layer used in Example 1 was changed as follows. Evaluation was performed in the same manner as in Example 1.

Silicone Rubber Layer Composition <Solid Component 10%> (1) 100 parts by weight of α, ω-divinylpolydimethylsiloxane (degree of polymerization 770) (2) HMS-151 (manufactured by Chisso Corp. (Gen siloxane) (dimethyl siloxane) copolymer Number of SiH groups / molecular weight = 0.25 mol / g) 4 parts by weight (3) 0.02 parts by weight of olefin-coordinated platinum (4) 0.3 parts by weight of reaction inhibitor <solvent Ingredients> (5) "Isopar" E (manufactured by Esso Chemical Co., Ltd.) The number of SiH groups per one vinyl group in the above silicone rubber layer composition was about 2.9.

Example 7 A negative type waterless planographic printing plate precursor was prepared in the same manner as in Example 1 except that the composition of the silicone rubber layer used in Example 1 was changed as follows, and evaluated in the same manner as in Example 1. went.

Silicone Rubber Layer Composition <Solid Component 10%> (1) 100 parts by weight of α, ω-divinylpolydimethylsiloxane (degree of polymerization 770) (2) SH-1107 (manufactured by Dow Corning Silicone Toray Co., Ltd.) Terminal methyl polymethyl hydrogen siloxane Number of SiH groups / molecular weight = 1.67 mol / g) 3 parts by weight (3) Olefin-coordinated platinum 0.02 parts by weight (4) Reaction inhibitor 0.3 parts by weight <Solvent component> ( 5) "Isopar" E (manufactured by Esso Chemical Co., Ltd.) The number of SiH groups per 1 vinyl group in the above silicone rubber layer composition was about 13.8.

Example 8 A negative type waterless planographic printing plate precursor was prepared in the same manner as in Example 1 except that the composition of the silicone rubber layer used in Example 1 was changed as follows, and evaluated in the same manner as in Example 1. went.

<Solid component: 10%> (1) 100 parts by weight of α, ω-divinylpolydimethylsiloxane (degree of polymerization 770) (2) HMS-501 (manufactured by Chisso Corp., both ends methyl (methyl hydrogen siloxane)) (Dimethylsiloxane) copolymer Number of SiH groups / molecular weight = 0.69 mol / g) 1 part by weight (3) 0.02 parts by weight of olefin-coordinated platinum (4) 0.3 parts by weight of reaction inhibitor <Solvent component> ( 5) "Isopar" E (manufactured by Esso Chemical Co., Ltd.) The number of SiH groups per one vinyl group in the above silicone rubber layer composition was about 2.0.

Examples 9 to 10 In Example 9, the acetone pyrogallol resin having a quinonediazide group used in Example 1 was replaced with the acetone pyrogallol resin having a quinonediazide group obtained in Synthesis Example 4 (esterification degree: 3%). In Example 10, a waterless lithographic plate was produced in the same manner as in Example 1 except that the quinonediazide-containing acetone pyrogallol resin having a quinonediazide group (esterification degree: 70%) was used. Were evaluated for image reproducibility and storage stability.

Example 11 A negative waterless planographic printing plate precursor was prepared in the same manner as in Example 1 except that the composition of the photosensitive layer used in Example 1 was changed to the following composition, and evaluated in the same manner as in Example 1. Was done.

Photosensitive Layer Composition <Solid Component: Coating Concentration 10%> (1) Acetone pyrogallol resin having a quinonediazide group obtained in Synthesis Example 1 (degree of esterification: 33%) 70 parts by weight (2) 4,4′- 2.2 parts by weight of diphenylmethane diisocyanate (3) 30 parts by weight of polyurethane resin "SAMPLEN LQ-T1331" (manufactured by Sanyo Chemical Industries, Ltd.) (4) 0.2 parts by weight of dibutyltin diacetate (5) P-toluenesulfonic acid 0.8 part by weight <Solvent component> (6) Tetrahydrofuran Example 12 A negative waterless planographic printing plate precursor was prepared in the same manner as in Example 1 except that the composition of the photosensitive layer used in Example 1 was changed to the following composition. It was fabricated and evaluated in the same manner as in Example 1.

Photosensitive Layer Composition <Solid Component: Application Concentration 10%> (1) Acetone pyrogallol resin having a quinonediazide group obtained in Synthesis Example 1 (degree of esterification: 33%) 70 parts by weight (2) 4,4′- Diphenylmethane diisocyanate 105 parts by weight (3) Polyurethane resin “SAMPLEN LQ-T1331” (manufactured by Sanyo Chemical Industries, Ltd.) 30 parts by weight (4) Dibutyltin diacetate 0.2 part by weight (5) P-toluenesulfonic acid 8 parts by weight <solvent component> (6) Tetrahydrofuran Example 13 A negative waterless planographic printing plate precursor was prepared in the same manner as in Example 1 except that the composition of the silicone rubber layer used in Example 1 was changed to the following composition. Then, evaluation was performed in the same manner as in Example 1.

Silicone Rubber Layer Composition <Solid Component 10%> (1) 100 parts by weight of α, ω-divinylpolydimethylsiloxane (degree of polymerization 770) (2) HMS-013 (manufactured by Chisso Corp. (Gen siloxane) (dimethyl siloxane) copolymer SiH group number / molecular weight = 0.01 3 mol / g) 50 parts by weight (3) 0.02 parts by weight of olefin-coordinated platinum (4) 0.3 parts by weight of reaction inhibitor <solvent Ingredients> (5) "ISOPAR" E (manufactured by Esso Chemical Co., Ltd.) The number of SiH groups with respect to 1 vinyl group in the above silicone rubber layer composition was about 1.9.

Example 14 A negative waterless planographic printing plate precursor was prepared in the same manner as in Example 1 except that the composition of the silicone rubber layer used in Example 1 was changed to the following composition. An evaluation was performed.

Silicone Rubber Layer Composition <Solid Component 10%> (1) 100 parts by weight of α, ω-divinylpolydimethylsiloxane (degree of polymerization 770) (2) HMS-501 (manufactured by Chisso Corp. (Gen siloxane) (dimethyl siloxane) copolymer Number of SiH groups / Molecular weight = 0.69 mol / g) 10 parts by weight (3) Olefin-coordinated platinum 0.02 parts by weight (4) Reaction inhibitor 0.3 parts by weight <Solvent Ingredients> (5) "Isopar" E (manufactured by Esso Chemical Co., Ltd.) The number of SiH groups with respect to 1 vinyl group in the above silicone rubber layer composition was about 19.8.

Comparative Example 1 Negative water was obtained in the same manner as in Example 1 except that the silicone rubber layer used in Example 1 was changed to a silicone rubber composition of the condensation type shown below, which was applied under the following conditions. A lithographic printing plate precursor was prepared and evaluated in the same manner as in Example 1.

The following condensation type silicone rubber composition was applied with a bar coater, and heat-cured at 130 ° C. for 2 minutes to obtain 2 g
/ M ² of silicone rubber layer.

Silicone Rubber Layer Composition <Solid Component 10%> (1) 90% by weight of hydroxyl-terminated polydimethylsiloxane (degree of polymerization: 700) (2) 9.8 parts by weight of tris (methylethylketoxime) vinylsilane (3) dibutyltin Dilaurate 0.2 parts by weight <Solvent component> (4) "Isopar" E (manufactured by Esso Chemical Co., Ltd.) Comparative Example 2 The same as in Example 1 except that the photosensitive layer composition used in Example 1 was changed to the following composition. In the same manner, a negative type waterless planographic printing plate precursor was prepared and evaluated in the same manner as in Example 1.

Photosensitive Layer Composition <Solid Component: Coating Concentration 10%> (1) Acetone pyrogallol resin having a quinonediazide group obtained in Synthesis Example 1 (degree of esterification: 33%) 70 parts by weight (2) Polyurethane resin “SAMPLEN LQ” -T1331 "(manufactured by Sanyo Chemical Industries, Ltd.) 30 parts by weight (3) Dibutyltin diacetate 0.2 part by weight (4) P-toluenesulfonic acid 0.8 part by weight <Solvent component> (5) Tetrahydrofuran Table 1 shows the results of evaluating the image reproducibility and storage stability of Comparative Examples 1 to 14 and Comparative Examples 1 and 2, and Table 2 shows the compositions of the silicone rubber layers used.

[0140]

[Table 1]

[Table 2] In Table 1, in the printing plate of Comparative Example 2, all the image portions and a part of the photosensitive layer in the non-printing image portion were dissolved at the time of development, and a good printing plate was not obtained. This result indicates that the acetone pyrogallol resin having a quinonediazide group in the photosensitive layer must form a crosslinked structure.

Further, since the difference in GS sensitivity between the initial stage and after forced storage was small and the storage stability was excellent in all the examples as compared with Comparative Example 1, acetone pyrogallol having a quinonediazide group having a crosslinked structure was obtained. It can be seen that image reproducibility and storage stability are improved by the combination of the photosensitive layer containing the resin and the additional silicone rubber layer.

Further, it can be seen that the image reproducibility and storage stability are further improved by setting the amount of the crosslinking agent in the photosensitive layer in the range described in the claims.

[0143]

According to the present invention, there is provided a waterless planographic printing plate precursor obtained by laminating a photosensitive layer and a silicone rubber layer in this order on a substrate, wherein the photosensitive layer contains an acetone pyrogallol resin having a quinonediazide group. When the acetone pyrogallol resin forms a crosslinked structure and the addition type silicone rubber is used for the silicone rubber layer, a waterless planographic printing plate precursor having good image reproducibility and excellent storage stability can be obtained.

Claims (8)

[Claims] 1. A waterless lithographic printing plate precursor comprising at least a primer layer, a photosensitive layer and a silicone rubber layer laminated in this order on a substrate, wherein the photosensitive layer has a quinonediazide group having a crosslinked structure and an acetone pyrogallol resin. And the silicone rubber layer has a vinyl group and SiH
A waterless lithographic printing plate precursor characterized by being cured by the addition reaction of a group. 2. An acetone pyrogallol resin represented by the following general formula 1.
The lithographic printing plate precursor according to claim 1, wherein the lithographic printing plate precursor is waterless. Embedded image (Wherein X, Y, and Z each independently represent a hydroxyl group or a sulfonic ester group of quinonediazide; n is 5
Represents an integer of from 12 to 12. ) 3. A silicone rubber layer comprising an organopolysiloxane having at least two vinyl groups in a molecule, a hydrogen siloxane having at least three SiH groups in a molecule, and a platinum compound. Waterless planographic printing plate precursors as described in Nos. 1 to 2. 4. The waterless planographic printing plate precursor according to claim 1, wherein the value of the number of SiH groups / molecular weight in the molecule of the hydrogen siloxane is 0.001 mol / g or more. 5. The lithographic printing plate precursor according to claim 1, wherein the ratio of the number of SiH groups to the number of vinyl groups in the silicone rubber layer is in the range of 1.5 to 15. 6. The acetone pyrogallol resin is esterified with 1,2-naphthoquinone-2-diazide-5-sulfonic acid chloride or 1,2-naphthoquinone-2-diazide-4-sulfonic acid chloride. The degree is 5-67%.
The waterless planographic printing plate precursor described. 7. The lithographic printing plate precursor according to claim 1, wherein the acetone pyrogallol resin is cross-linked by an isocyanate compound. 8. The method according to claim 1, wherein the content of isocyanate in the photosensitive layer is 5 to 45% by weight based on the acetone pyrogallol resin having a quinonediazide group.
The waterless planographic printing plate precursor described.