JPS63280251A - Production of damping waterless planographic printing plate - Google Patents

Abstract

PURPOSE:To obtain a stable image and to enable development with water or a low-polluting developing soln. essentially consisting of water by incorporating a specific solvent soluble high-molecular polymer and photopolymn. initiator into a photosensitive layer. CONSTITUTION:The photosensitive layer contains the solvent soluble high- molecular polymer of 5000-1,000,000mol.wt. having a photopolymerizable ethylenic unsatd. double bond group and hydroxyl group at the side chain or a mixture composed of 95-50wt.% solvent soluble high-molecular polymer of 5,000-1,000,000mol.wt. having the photopolymerizable ethylenic unsatd. double bond group at the side chain and 5-50wt.% solvent soluble high-molecular polymer of 5,000-1,000,000mol.wt. having the hydroxyl group at the side chain and the photopolymn. initiator. The excellent adhesiveness to a silicon rubber layer is obtd. and the development with the water or the low-polluting developing soln. essentially consisting of the water is enabled by using the polymer having the hydroxyl group and the ethylenic unsatd. group in the photosensitive layer in such a manner.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing a photosensitive lithographic printing plate that does not require dampening water, using a lithographic printing plate that does not require dampening water.

[Conventional technology]

Various types of dampening water-free photosensitive lithographic printing plates have been proposed for performing planographic printing without using dampening water. Among these, those in which a photosensitive resin layer and a silicone rubber layer are sequentially coated on a substrate have extremely excellent performance. ing.

The silicone rubber layer used in these lithographic printing plates that do not require dampening water is usually partially crosslinked using a polymer having a main skeleton of polysiloxane and a crosslinking agent. For the photosensitive layer, developers such as those described in Japanese Patent Publication No. 42-21879, Japanese Patent Publication No. 46-16044, Japanese Patent Application Publication No. 49-86103, Japanese Patent Application Publication No. 49-68803, and Japanese Patent Publication No. 55-22781 are used. It is described in Japanese Patent Publication No. 54-26923, Japanese Patent Publication No. 56-23150, and Japanese Patent Publication No. 56-12861 that the unexposed area (image area) is dissolved and the upper silicone rubber layer is removed accordingly. In some cases, the exposed areas (non-image areas), such as those shown in FIG. The former, which elutes the photosensitive layer, is
Since the photosensitive layer in the unexposed area (image area) is dissolved and the silicone rubber layer above it is forcibly removed to form an image, the adhesion between the photosensitive layer and the silicone rubber layer above it is sufficient. Otherwise, part of the photosensitive layer of the silicone rubber layer in the exposed area (non-image area) will peel off during development, making it impossible to form a stable image.

Therefore, for example, JP-A No. 49-73202 and JP-A No. 4
There has been an attempt to strengthen the adhesive force between the photosensitive layer and the silicone rubber layer by adding a silane coupling agent such as that described in Japanese Patent No. 9-86130 to the photosensitive layer or the silicone rubber layer. Although the adhesive strength is improved to some extent by adding a silane coupling agent, it is still insufficient. The latter, which utilizes photoadhesion to form images, uses a solvent that swells only the silicone rubber layer but does not elute the photosensitive layer;
For example, it can only be developed with a hydrocarbon solvent such as kerosene or Isopar G, which poses a pollution problem.

[Problem that the invention seeks to solve]

Therefore, the object of the present invention is to firmly adhere the photosensitive layer and the silicone rubber layer in advance so that the silicone rubber layer in the exposed areas (non-image areas) does not peel off during development and to obtain a stable image. This is a method for producing a dampening water-free planographic printing plate using a dampening water-free photosensitive planographic printing plate that can be developed with a low-pollution developer.

[Means for solving problems]

The present inventors have made extensive studies to solve these problems, and as a result, have arrived at the present invention.

In the present invention, a photosensitive lithographic printing plate formed by successively laminating a photosensitive layer and a silicone rubber layer on a substrate is exposed imagewise, and after being immersed in a developer that dissolves or swells the photosensitive layer in the unexposed areas, the photosensitive layer in the unexposed areas is exposed. In a method for producing a lithographic printing plate that does not require dampening water and includes a step of removing a photosensitive layer and a silicone rubber layer in a portion in contact with the photosensitive layer, the photosensitive layer has (1) a photopolymerizable ethylenically unsaturated double bond in the side chain; Molecular weight 5.000-1, having a group and a hydroxyl group
000.000 solvent-soluble polymers or side chains! 95 to 50% by weight of a solvent-soluble polymer with a molecular weight of 5,000 to 1,000.000 having a photopolymerizable ethylenically unsaturated double bond group and a molecular weight of 5 having a hydroxyl group in the side chain.
．． Fountain water-free lithographic printing characterized by being a photosensitive composition containing a mixture of 5 to 50% by weight of a solvent-soluble polymer having a molecular weight of 000 to 1.000.000 and (2) a photopolymerization initiator. This is a method of manufacturing plates.

In the present invention, it is believed that the high molecular weight polymer having hydroxyl groups in the photosensitive layer is chemically bonded to the silicone rubber layer during the drying process when the silicone rubber layer is coated, and becomes firmly adhered to the silicone rubber layer. By introducing a photopolymerizable ethylenically unsaturated group into the polymer,
Dense crosslinking is obtained by exposure to light, and the photosensitive layer in exposed areas (non-image areas) is less likely to swell with a developer during development. - By introducing a hydroxyl group into the blade polymer, the photosensitive layer in the unexposed area (image area) becomes more easily eluted or swollen in a water-based developer, making development easier. In this way, by using a polymer having hydroxyl groups and ethylenically unsaturated groups in the photosensitive layer, it has excellent adhesion to the silicone rubber layer and can be developed with water or a low-pollution developer mainly composed of water. Become. The polymer used in the present invention may be a blend in which a photopolymerizable ethylenically unsaturated group and a hydroxyl group are introduced into the side chain at the same time, or in which they are introduced separately.

The specific polymer having a photopolymerizable ethylenically unsaturated group and a hydroxyl group in its side chain, which is the component (a) used in the present invention, has the following general formula <1 described in JP-A No. 59-46643. ), [wherein Rr to R3 are hydrogen, halogen, carboxyl, sulfo, nitro, amide,
A group selected from amino and alkyl, aryl, alkoxy, aryloxy, alkylamino, arylamino, alkylsulfonyl and arylsulfonyl each optionally having a substituent, and Z is oxygen, sulfur, NH or NR(R is selected from alkyl groups). ] Monomers having hydroxyl groups (for example, copolymers consisting of hydroxyethyl methacrylate, hydroxypropyl methacrylate, polyethylene glycol monomethacrylate, polyethylene glycol monomers, and other monomers; vinyl methacrylate, the above monomers having hydroxyl groups, and as necessary) and other monomers; (meth)acrylic acid copolymers and crotonic acid copolymers in which carboxylic acid is reacted with glycidyl (meth)acrylate, hydroxyalkyl (meth)acrylate copolymers, polyvinyl Formal, polyvinyl butyral partially reacted with maleic anhydride or itaconic anhydride; 2.4 toluene diisocyanate/hydroxyalkyl (meth)acrylate = 1/1 addition to hydroxyalkyl (meth)acrylate copolymer An example is a product in which a substance is partially reacted; a product in which a (meth)acrylic acid copolymer is partially reacted with allyl glycidyl ether.

Examples of the polymer having a photopolymerizable ethylenically unsaturated double bond group in the side chain, which is (i) of component (i) of the present invention and used as one of the components (5) in the present invention, include allyl methacrylate; Polymers, vinyl methacrylate copolymers, maleic anhydride copolymers with pentaerythritol triacrylate added through half-esterification, styrene/
Maleic anhydride copolymer with monohydroxyalkyl (meth)acrylate, polyethylene glycol mono (meth)acrylate or polypropylene glycol mono (meth)acrylate added by half-esterification, and polymers containing hydroxyl groups in the side chains. 2.4 Toluene diisocyanate/hydroxyethyl (meth)acrylate = 1
/1 adduct, reacted with N-methylolacrylamide to a polymer containing a hydroxyl group in its side chain, reacted with hydroxyl, and polymerized with a hydroxyl group in its side chain.

The polymer having a hydroxyl group to be combined with the other component (c) (ii) having a photopolymerizable ethylenically unsaturated double bond group in its side chain is the polymer of component (a). Homopolymers and copolymers of monomers having hydroxyl groups such as hydroxyethyl (meth)acrylate, hydroxypropylene (meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate,
Examples include epoxy resin, phenoxy resin, polyvinyl formal, polyvinyl butyral, partially acetalized polyvinyl alcohol, cellulose diacetate, polyvinyl alcohol, gelatin, casein, starch, and cellulose derivatives. The blend ratio of the polymer having an unsaturated group in the side chain and the polymer having a hydroxyl group is 95:5 to 50:50 by weight, preferably 85:5.
15:30 to 70:30.

The amount of these components (1) based on the total photosensitive composition is 30
-99% by weight, preferably 50-97% by weight.

In the present invention, if necessary, a monomer or oligomer having at least one photopolymerizable ethylenically unsaturated double bond may be included in the photosensitive composition. These monomers or oligomers include monofunctional acrylates and methacrylates such as polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, and phenoxyethyl(meth)acrylate; polyprolene glycol di(meth)acrylate, and trimethylol. etantori (meta)
Acrylate, onepentyl glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, hexanediol di(meth)acrylate, trimethylolpropane tri(acryloyl) After adding ethylene oxide or propylene oxide to polyfunctional alcohols such as oxypropyl) ether, tri(acryloyloxyethyl) isocyanurate, calcium (meth)acrylate, barium (meth)acrylate, glycerin or trimethylolethane. (Meth) acrylate, Special Publication No. 41708 of 1983, Special Publication of Publication No. 1973-
Urethane acrylates such as those listed in Japanese names in JP-A-6034 and JP-A-51-37193, JP-A-Sho. 48-
No. 64183, Special Publication No. 49-43191, Special Publication No. 1977
Polyester acrylates listed in Japanese names in each publication No. 30490, polyfunctional acrylates and methacrylates such as epoxy acrylates made by reacting epoxy resin with (meth)acrylic acid, N-methylol described in U.S. Patent No. 4,540,649 Examples include acrylamide derivatives.

Furthermore, Japan Adhesive Section Journal Vol. 20, Nα7.300
Those introduced as photocurable polymers and oligomers on pages 308 to 308 can also be used.

The composition ratio of these monomers or oligomers to the polymer is preferably in the range of 0:10 to 7:3 by weight, and more preferably in the range of 1.5:8.5 to 5:5.

Examples of the photopolymerization initiator used in the present invention include vicinal polyketaldonyl compounds disclosed in U.S. Pat. No. 2.367.660 and U.S. Pat. No. 2.367.6.
61 and 2.367,670, U.S. Pat. No. 2,448.8
28, α-hydrocarbon-substituted aromatic acyloin compounds disclosed in U.S. Pat. No. 2,722,512, U.S. Pat. No. 3,046,127. No. 2,951.75
8, triarylimidazole dimer/p-aminophenyl ketone combinations as disclosed in U.S. Pat. No. 3,549,367, U.S. Pat. No. 3,870, Benzothiazole compounds disclosed in U.S. Pat. No. 524, benzothiazole compounds/trihalomethyl-5)IJ azine compounds disclosed in U.S. Pat. No. 4,239.850, and U.S. Pat. These include acridine and phenazine compounds disclosed in U.S. Pat. No. 751.259, oxadiazole compounds disclosed in U.S. Pat.
Trihalomethyl-5-)riazine and trihalomethyloxadiazole, which have a light absorption maximum at nm, are useful.

Examples of specific compounds include the following.

The amount of these photopolymerization initiators added is 0.1 to the total composition.
-20% by weight, preferably 1-10% by weight.

In addition to the above, it is preferable to add a thermal polymerization inhibitor, such as hydroquinone, P-methoxydiphenol, di-t-butyl-p-cresol, pyrogallol, t
-Butylcatechol, benzoquinone, 4.4'-thiobis(3-methyl-6-t-butylphenol), 2.2
'-Methylenebis(4-methyl-6-t-butylphenol), 2-mercaptobenzimidazole, etc. are useful, and in some cases, dyes or pigments or pH indicators as printing agents are added for the purpose of coloring the photosensitive layer. You can also. Other water-soluble polymers such as polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, partially acetalized polyvinyl alcohol, water-soluble nylon, water-soluble urethane, gum arabic, water-soluble cellulose derivatives, gelatin, etc. may be added as necessary. You can also do that.

Examples of the solvent used in the present invention include 2-methoxyethanol, 2-methoxyethyl acetate, methanol, ethanol, methyl ethyl ketone, and water, which may be used alone or as a mixed solvent in an appropriate combination. The photopolymerizable composition is dissolved in these solvents and provided on the support, and the coating amount is suitably in the range of about 0.1 g/rn', s to about 10 g/rn', and more. Preferably it is 0.5-5 g/rn'.

As this low filler, inorganic fine powders such as colloidal silica, calcium carbonate, magnesium carbonate, iron oxide, etc. may be added. In order to improve the adhesion with the silicone rubber layer and the silicone rubber layer, a silane coupling agent described in JP-A No. 49-86130 and a titanate known under the trade name Blenact sold by Ajinomoto Co., Ltd. A type coupling agent or an aluminum type coupling agent may be added to the photosensitive layer.

The silicone rubber preferably used in the present invention is a linear or partially crosslinked polydiorganosiloxane having the following repeating units.

where R represents a monovalent amount of alkyl, aryl, alkenyl or a combination thereof, including halogen, amine, hydroxy, alkoxy, aryloxy,
It may have a functional group such as (meth)acryloxy or thiol. In addition, silicone rubber may contain fine powders of inorganic substances such as silica, calcium carbonate, and titanium oxide, adhesion aids and photopolymerization with the aforementioned silane coupling agents, titanate coupling agents, and aluminum coupling agents. An initiator may also be added.

High molecular weight polymer whose main skeleton is the above-mentioned polysiloxane (
Polysiloxane with a molecular weight of several thousand to several hundred thousand and has a functional group at the end is used as a raw material for silicone rubber.
This is crosslinked and cured in the following manner to obtain a silicone rubber layer. Specifically, a silane crosslinking agent represented by the following general formula is introduced into the polysiloxane having hydroxyl groups at both ends, and if necessary, an organometallic compound such as an organotin compound, an inorganic acid, an amine, etc. The polysiloxane and the silane crosslinking agent are condensed and cured by heating or at room temperature.

Lsix4-R Here, n is an integer of 1 to 3, R is the same substituent as R shown above, and X represents a substituent such as -○H, -OR', -■. Here, R2 and R3 have the same meaning as .R described above, and R2 and R3 may be the same or different. Moreover, AC represents an acetyl group.

In addition, the above-mentioned silane crosslinking agent can be added to the organopolysiloxane having a hydroxyl group at the terminal and the hydrogen polysiloxane crosslinking agent as necessary, and condensation curing can be carried out.

The substrate used in the present invention may be the aluminum plate, iron plate, zinc plate, etc. used for general 28 plates, as is, or may be subjected to caustic treatment or anodizing treatment as necessary, or may be grained. , grained and then causticized or anodized, and if necessary, a primer layer of a suitable polymer may be applied, and the primer layer may be coated with an antihalation dye or a printout. Agents such as trihalomethyl compounds which are photoacid generators and pH indicators may be added. Further, the above-mentioned silane coupling agent, titanate coupling agent, or aluminum coupling agent may be added to the primer layer for the purpose of improving adhesiveness with the photosensitive layer and the metal substrate.

In addition, considering the dyeability of the plate after development and plate making, it is also possible to add a photopolymerizable monomer to one layer of the primer so that the photocured areas in the exposed areas are less likely to be dyed compared to the unexposed areas. It is valid. It is also effective to add a white pigment such as TiO2 to the primer layer in order to improve plate inspection properties after staining. Generally, the primer layer is epoxy resin, polyvinyl formal, phenoxy resin, butyral resin, acrylic resin, polyvinyl chloride,
Phenol resin, polyurethane resin, etc. are used.

Among these, polyvinyl formal having hydroxyl groups,
A single layer of primer made of phenoxy resin or butyral resin and heat-cured using a polyfunctional incyanate compound as a curing agent is preferable because it has water resistance and solvent resistance.

A polymer film may be used as the substrate. For example, a polyester film or a cellulose acetate film having good dimensional stability may be used. If a cheaper plate is sufficient, it is also possible to use water-resistant paper. Laminated paper obtained by processing paper with polymer or paper laminated with aluminum foil can be used.

The thickness of the silicone rubber layer used in the present invention is preferably as thin as possible from the viewpoint of tone reproducibility, and a certain thickness is required from the viewpoint of printing durability and printing stains, so 0.5~
Approximately 10μ is appropriate, and usually 0.7 to 2.5μ is desirable.

Furthermore, a protective film such as a polyester terephthalate film, a polypropylene film, a polyvinyl chloride film, a polyvinyl alcohol film, etc. may be provided on the silicone rubber layer of the dampening water-free photosensitive lithographic printing plate of the present invention, if necessary. good.

The photosensitive lithographic printing plate that does not require dampening water according to the present invention is exposed through a transparent original image, and then developed with water or a water-based developer that dissolves the photosensitive layer in the image area. The silicone rubber layer in contact with is removed to obtain a lithographic printing plate that does not require dampening water. In a developer mainly composed of water, an organic solvent having a solubility in water of 10% by weight or less at room temperature, 10% by weight or less of toehabenzyl alcohol or phenyl cellosolve, and 10% by weight or less of a nonionic surfactant, An anionic surfactant and, in some cases, a cationic surfactant to increase the oil sensitivity of the image area, are added so that the water content is 80% by weight or more.

Developing is done by rubbing with a vat containing the developer mentioned above,
This can be done by a known method such as immersion in a developer and then rubbing with a developer brush. At this time, in order to increase the development speed, the temperature of the developer may be increased to 50 to 60°C. As a result, the silicone rubber layer and photosensitive layer in the image area are removed, and the surface of the substrate or primer layer is exposed, and that area becomes an ink receiving area.

〔Effect of the invention〕

The lithographic printing plate that does not require dampening water according to the present invention is made with water or a low-pollution developer mainly composed of water, and the silicone rubber layer in the non-image area (exposed area) of the printing plate after plate making and the photosensitive layer thereunder. The layers adhere strongly and have stable reproducibility.

〔Example〕

The present invention will be explained in more detail below with reference to Examples.

Example 1 A photosensitive brimer solution having the following composition was applied onto a degreased smooth aluminum plate with a thickness of 0.3 cm, and heated at 120°C.
, dried for 1 minute. The coating weight after drying is 4 g/
It was m'.

Epi: l-) 1255-HX-30 (30% solution) 5g bamboo shoot) D-11ON 1.5g (75
% solution) Trimethylolpropanethria 1 g Acrylate 0,02 g 0,01 g Methyl ethyl ketone 30 g Propylene glycol monomethyl ether acetate 30 g Next, a water-soluble photosensitive solution having the following composition was applied and dried at 100° C. for 2 minutes. Dry coating weight was Log/m.

Pentaerythritol triacrylate 0.7g poly (allyl methacrylate/potassium methacrylate 1.5g: copolymerization molar ratio 80/20) (molecular weight 40.000) Nisrex W-2012, 0g (manufactured by Sekisui Blastex ■) : Water-soluble polyvinyl acetal resin) (25% aqueous solution) (Molecular weight 40,000) 0.1g Water 2
5 g methanol 15 g A silicone solution having the following composition was applied onto this photosensitive layer and dried at 120° C. for 1 minute. Dry coating weight is 1.25
g/m'.

Dimethylpolysiloxane (molecular weight approximately 100,000) 30g ■ 0.3g 0.3g Dibutyltin acetate 0.1g Isopar G (petroleum solvent) 180g An 8 micron thick polyethylene terephthalate film was laminated onto the plate prepared as described above. This was used as the original printing plate.

A positive film was brought into close contact with this printing original plate, and exposed for 30 seconds using a vacuum printer FT26V (light source, 2KW metal halide lamp) manufactured by Nuark, USA. After exposure, the cover film was removed, and the plate was immersed in warm water at 50° C. for 30 seconds, and then the plate surface was rubbed with a sponge for 30 seconds to remove the silicone layer and photosensitive layer in the unexposed areas. Thereafter, only one layer of the primer in the unexposed area was dyed with the following staining solution to obtain a waterless lithographic printing plate.

Benzyl alcohol 5g water
95 g Victoria Beer Pull BOH 2 g Nonionic surfactant 2 g Example 2 The following brimer composition was applied in one layer to a dry coating weight of 4.0 g/m'' on a smooth aluminum plate that had been degreased in the usual manner, and then heated at 120°C. Heat for 5 minutes to dry and harden.

Epicor) 1001 Log (
Bisphenol A-based epoxy resin manufactured by Shell Chemical Epoxy equivalent weight 450 Methyltetrahydrophthalic anhydride 3.6g2.
4.6-) Lis(dimethylaminomethyl)phenol 1g Benzanthrone 0.6g TIPAQU
E R-930 (manufactured by Ishihara Sangyo ■) 0.5 g
Methyl cellosolve acetate 60g Toluene 60g Methyl ethyl ketone 60g The following photosensitive composition was coated on a smooth aluminum plate coated with a single layer of the above-mentioned brimer so as to have a dry weight of Ig/m'' and dried at 100°C for 1 minute.

Poly(allyl methacrylate/2-hydroxyethyl methacrylate 7g: copolymerization molar ratio 80/20) (molecular weight 40.000) Pentaerythritol triacrylate 3g0.
6g.

0.15 g Propylene glycol monomethyl ether acetate 110 g Methyl ethyl ketone 50 g Xylene
60g Next, the following silicone rubber composition was applied onto the photosensitive layer at a dry weight of 2.0g/m''.
The silicone rubber cured layer was formed by coating the film and drying it at 120°C for 2 minutes to form a cured silicone rubber layer.

Dimethylpolysiloxane having hydroxyl groups at both ends 10g Vinyltri(methylethylketoxime)silane 0.35g Vinyltriacetoxysilane 0.35g Dibutyltin dioctanoate) 0.03g Fi7
/(-G (manufactured by EXXONXX-) 200g A layer with a thickness of 12
A single-sided matted polyethylene terephthalate film of μ was laminated to obtain a photosensitive lithographic printing original plate that does not require dampening water.

This printing plate was imagewise exposed in the same manner as in Example 1, immersed in the following developer at 35° C. for 1 minute, and then thoroughly rubbed with a vat. The photosensitive layer in the image area and the silicone rubber layer thereon were cleanly removed without damaging the silicone rubber layer in the non-image area.

Benzyl alcohol 10g Sodium isopropylnaphthalene sulfonate 3.5g Water
86.5
g Thereafter, only one layer of the unexposed area of the brimer was dyed with the following dyeing solution to obtain a lithographic printing plate that did not require dampening water.

Benzyl alcohol 5g water
95g
Crystal Violet 2g Using a lithographic printing plate that does not require dampening water, which faithfully reproduces the positive film image over the entire surface of the printing plate, the Toyo Ink side TOYOKING ULTRA was printed on a Heidelberg GTO printing machine with the dampening water supply device removed. When printed with TUK Aquares G black ink, a printed matter showing faithful image reproducibility was obtained.

Example 3 Instead of the photosensitive layer of Example 2, a photosensitive liquid having the following composition was coated to the same dry coating weight.

Poly (vinyl methacrylate/2-hydroxyethyl methacrylate 7g: copolymerization molar ratio 80/20) (molecular weight 40,000) Dipentaerythritol tetraacrylate 3g0.3
g Victoria Vinierpur-BOH0.12g Propylene glycol monomethyl ether 110g Methyl ethyl ketone 50g Xylene
60g A lithographic printing plate similar to Example 2 and requiring no dampening water was obtained.

Example 4 In place of the photosensitive layer of Example 2, a photosensitive layer made of the following photosensitive liquid was used.

Poly (ethyl methacrylate/glycidyl methacrylate: copolymerization mole 7g ratio (70
/30) with methacrylic acid added (molecular weight 40.000) Pentaerythritol triacrylate 3g 0.3g 0.15g Propylene glycol monomethyl ether 110g Methyl ethyl ketone 110g A lithographic printing plate similar to Example 2 that does not require dampening water was prepared. Obtained.

Example 5 Instead of the photosensitive layer of Example 2, a photosensitive liquid having the following composition was coated to the same dry coating weight.

Poly(allyl methacrylate/2-hydroxyethyl methacrylate 10g: co-electrical molar ratio 90/10) (molecular weight 40.000) 3 υ, 3 g Oil Blue #603 (manufactured by Orient Chemical) 0.15 g metatol silica (30 % solution) 1 g Propylene glycol monomethyl ether 110 g Methyl ethyl ketone 110 g A lithographic printing plate similar to Example 2 and requiring no dampening water was obtained.

Example 6 The following photosensitive solution was applied onto the substrate coated with a single layer of the brimer of Example 1 and dried at 100° C. for 2 minutes. The dry coating weight was 1 g/m'.

Pentaerythritol triacrylate 0.6 g Triethylene glycol dimethacrylate 0.3 g Poly (allyl methacrylate/2-hydroxyethyl methacrylate/methacrylic acid: copolymerization molar ratio 75/10/15) 1.5 g sodium salt (molecular weight 40,000) 0.2g water
20g methanol 20
g Next, the following silicone rubber composition was coated on the photosensitive layer at a dry weight of 1.0 g/m', and heated at 120°C.
It was dried for 2 minutes to obtain a cured silicone rubber layer.

Dimethylpolysiloxane having hydroxyl groups at both ends 10g (average molecular weight 600.000'') Methyl hydrogen polysiloxane having trimethyl groups at both ends 0.35g Loxane (average molecular weight 2.500) Trimethoxysilylpropyl-3,5- Diallylisocyanurate 0.35 g
dibutyltin dioctanoate) 0.33 g
Isopar G (manufactured by EXXON Kagaku ■) 200g A single-sided matted polypropylene film having a thickness of 12 μm was laminated on the surface of the silicone rubber layer obtained as above to obtain a photosensitive lithographic printing plate precursor that did not require dampening water.

This printing original plate was imagewise exposed and developed in the same manner as in Example 1 with warm water to obtain a lithographic printing plate that did not require dampening water.

Example 7 Instead of the photosensitive layer of Example 2, a photosensitive liquid having the following composition was coated to the same dry coating weight.

Poly(allyl methacrylate/2-hydroxyethyl methacrylate 7g: copolymerization molar ratio 80/20) (molecular weight 40.000) Pentaerythritol triacrylate 3g0.3
g Propylene glycol monomethyl ether acetate 110 g Methyl ethyl ketone 110 g Then Example 2
The same silicone rubber layer was provided, and a 12μ polyethylene terephthalate film was provided thereon.

The printing original plate produced in this way was heated with an Ar” laser (
488 nm), and then development and staining were carried out in the same manner as in Example 2 to obtain a lithographic printing plate that did not require dampening water and the scanning area became a non-image area. The sensitivity of the original printing plate measured at this time was 5 mJ/cut.

Procedural amendment 62.8. -5 Showa year, month, day 1, case description 1988 patent application No. 116239
No. 2, Title of the invention Method for producing a lithographic printing plate that does not require dampening water 3
, Person making the amendment, etc. Applicant name (520) Fuji Photo Film Co., Ltd. 4, Agent 5, Date of amendment order Initiator 6, Subject of amendment Detailed explanation of the invention in the specification (1) “The photosensitive layer peels off” on page 4, line 15 of the specification is “
"Peeling off from the photosensitive layer" is corrected.

(2) "Neopentyl glycol" in lines 2 and 3 of page 13 of the same book is corrected to "neopentyl glycol."

(3) In the same book, page 21, line 5, "-valent amount" is corrected to "-valent substituent."

Claims (1)

[Scope of Claims] A photosensitive lithographic printing plate formed by sequentially laminating a photosensitive layer and a silicone rubber layer on a substrate is imagewise exposed, and after being immersed in a developer that dissolves or swells the photosensitive layer in the unexposed areas, In a method for producing a lithographic printing plate that does not require dampening water, the method includes a step of removing a photosensitive layer in an exposed area and a silicone rubber layer in a portion in contact with the photosensitive layer,
The photosensitive layer comprises (1) (a) a solvent-soluble polymer having a molecular weight of 5,000 to 1,000,000 and having a photopolymerizable ethylenically unsaturated double bond group and a hydroxyl group in the side chain, or ( b
) (i) A solvent-soluble polymer having a molecular weight of 5,000 to 1,000,000 and having a photopolymerizable ethylenically unsaturated double bond group in the side chain and having no hydroxyl group95
~50% by weight and (ii) a molecular weight of 5 having a hydroxyl group in the side chain
,000 to 1,000,000, a mixture of 5 to 50% by weight of a solvent-soluble polymer having no photopolymerizable ethylenically unsaturated double bond in the side chain, and (2)
A method for producing a lithographic printing plate that does not require dampening water, characterized in that it is formed from a photosensitive composition containing a photopolymerization initiator.