JP2626987B2 - No fountain solution photosensitive lithographic printing plate - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a photosensitive lithographic printing plate used for producing a fountain solution-free lithographic printing plate capable of printing without using a fountain solution.

(Prior art)

Several inventions have been made in the past on lithographic printing plates that can be printed without using dampening water. For example, JP-B-44-23042, JP-B-46-16044, JP-B-51-17
No. 081, JP-B-54-26923, JP-A-56-80064, and JP-B-55-22781. Above all, the photosensitive layer of a positive-type photosensitive lithographic printing plate is disclosed in JP-B-54-2692.
No. 3, JP-B-56-23150, and a type using a photopolymerizable photosensitive layer disclosed in JP-B-56-23150 and a photo-dimerization-type photosensitive layer disclosed in JP-B-55-22781, are generally used.

In the type using the photopolymerizable photosensitive layer, a photo-adhesion phenomenon can be caused between the silicone rubber layer and the photosensitive layer by exposure, and therefore, an adhesion auxiliary agent for giving adhesion to the photosensitive layer in the silicone rubber layer ( It is not necessary to add a silane coupling agent. When using such photo-adhesion, by developing with a solvent that swells the silicone rubber layer, without dissolving the lower photopolymer layer,
Only the unexposed portions of the silicone rubber layer can be removed. However, since an image forming method using optical bonding is essentially used, the halftone dot reproducibility of a shadow portion where the amount of light is insufficient is not always sufficient. In order to solve this problem, an adhesion aid such as an aminosilane coupling agent is added to the silicone rubber layer, and the silicone rubber layer and the photosensitive layer are firmly adhered to each other from the beginning, and a developer for dissolving the photosensitive layer is used. There is a method of forming an image by dissolving the unexposed portion to the lower photopolymerized layer. When such a method is adopted, the halftone dot reproducibility of the shadow portion is improved. However, as time passes, the adhesive force between the photosensitive layer and the silicone rubber layer increases, thereby deteriorating the developability. As a result, the halftone dot reproducibility of the highlight portion may become poor.

On the other hand, in the type using the photodimerization type photosensitive layer, unlike the case where the photopolymerization type photosensitive layer is used, sufficient optical adhesion between the photosensitive layer and the silicone rubber layer cannot be obtained. It was necessary to add a silane coupling agent or the like as an auxiliary agent and strongly bond the silicone rubber layer and the photosensitive layer in advance. In this case, since the adhesion aid is used in the silicone rubber layer, the halftone dot reproducibility of the highlighted portion may be deteriorated with the passage of time as in the case of the photopolymerizable photosensitive layer.

[Problems to be solved by the invention]

Accordingly, it is an object of the present invention to provide a photosensitive lithographic printing plate which is excellent in image reproducibility and stable over time and requires no dampening solution.

[Means for solving the problem]

The present invention provides a photosensitive lithographic printing plate which does not require a fountain solution formed by laminating a photosensitive layer and a silicone rubber layer in this order on a substrate,
As silicone rubber layer Photopolymerization of a polymer having an ethylenically unsaturated double bond group capable of photopolymerization in the side chain as a photosensitive layer using a silicone rubber which is crosslinked by an addition reaction of -CH = CH- The invention is based on the finding that a photosensitive lithographic printing plate which is excellent in image reproducibility and stable over time and which does not require a fountain solution can be obtained by using the conductive composition.

That is, the present invention provides a substrate, a photosensitive layer provided on the substrate, and a photosensitive layer provided on the photosensitive layer. Water-free lithographic printing plate comprising a silicone rubber layer which is crosslinked by an addition reaction between -CH = CH- and -CH = CH- group, wherein the photosensitive layer has (1) at least two photopolymerizable groups on a side chain. A polymer having an ethylenically unsaturated double bond group and being soluble or swellable in water or alkaline water and capable of forming a film. (2) If necessary, at least one photopolymerizable ethylenic polymer An object of the present invention is to provide a photosensitive lithographic printing plate requiring no dampening solution, comprising a monomer or oligomer having an unsaturated double bond group and (3) a photopolymerization initiator.

The photosensitive lithographic printing plate requiring no dampening solution of the present invention must be flexible enough to be set in a normal printing machine and capable of withstanding the load applied during printing. Accordingly, typical substrates include coated paper, metal plates such as aluminum, plastic films such as polyethylene terephthalate, rubber, and composite substrates 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.

As the primer layer, various photosensitive polymers disclosed in JP-A-60-22903, which are exposed and cured before laminating a photosensitive layer, are disclosed in JP-A-62-50760.
The epoxy resin disclosed in Japanese Patent Application No. 61-281194 and the one obtained by hardening a gelatin layer disclosed in Japanese Patent Application No. 61-281194 are used. In addition, a hardened casein layer is also effective. Further, these primer layers may contain additives such as a dye, a printing-out agent, a polymerizable monomer as a photo-adhesive and a photo-polymerization initiator for the purpose of preventing halation and other purposes. Generally the coating thickness of the primer layer at a dry weight 2g / m ² ~10g / m ²
It is.

In the photosensitive layer of the present invention, at least 2
Having two photopolymerizable ethylenically unsaturated double bond groups,
Examples of the polymer capable of forming a film that is soluble or swellable in water or alkaline water include a water-soluble polymer such as polyvinyl alcohol and dextrin, and a carboxylic acid group, a carboxylic acid group, and a sulfonic acid in a side chain. Groups, sulfonate groups, phosphonate groups, phosphonate groups, amino groups and quaternary
Incorporating an ethylenically unsaturated double bond group such as a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, a fumarate group or a maleate group into a water-soluble or alkaline water-soluble polymer having a secondary amino group Can be mentioned.

Specifically, a hydroxyethyl (meth) acrylate / (meth) acrylic acid / methyl methacrylate copolymer disclosed in JP-B-59-45979 is reacted with (meth) acrylic acid chloride; Patent No. 3322
No. 994 or U.S. Pat. No. 4,451,613, in which polyvinyl alcohol or dextrin is reacted with (meth) acrylic acid chloride; this is disclosed in JP-B-49-5923 and JP-B-49-5922. N-methylolacrylamide reacted with polyvinyl alcohol;
A maleic anhydride copolymer disclosed in JP-A-59-71048 or JP-A-62-288603, to which pentaerythritol triacrylate is added by half-esterification;
Styrene / maleic anhydride copolymer obtained by adding monohydroxyalkyl (meth) acrylate, polyethylene glycol mono (meth) acrylate or polypropylene glycol mono (meth) acrylate by half esterification; disclosed in US Pat. No. 4,643,963. Cyclopentadiene / maleic acid copolymer; maleic anhydride
/ H- (hydroxyphenyl) maleimide / isobutylene copolymer in which monohydroxyalkyl (meth) acrylate is added by half-esterification; JP-A-62-53318
Dicyclopentenyl (meth) acrylate / methyl methacrylate / 2-hydroxyethyl methacrylate / dimethylaminoethyl methacrylate copolymer disclosed in JP-A-62-95525; geranyl methacrylate / methacryl disclosed in JP-A-62-95525 Acid copolymer; hydroxyalkyl (meth) acrylate copolymer, polyvinyl formal, polyvinyl butyral, phenoxy resin or hydroxypropylethylcellulose reacted with maleic anhydride or itaconic anhydride; polyether having hydroxyl group in side chain Olefinic unsaturated group-containing monoisocyanate partially added, followed by addition of an acid anhydride such as maleic anhydride or phthalic anhydride; to the phenolic resin disclosed in JP-A-62-157029. Glycidyl (meth) acryle Those obtained by adding the door; JP-B
Glycidyl (meth) acrylate added to a styrene / unsaturated carboxylic acid copolymer disclosed in JP-A-49-34041; (meth) acrylic acid copolymer, crotonic acid copolymer, cellulose acetate hydrogen phthalate ,
Polyvinyl alcohol hydrogen phthalate or a polyurethane obtained by adding dimethylolpropionic acid and diisocyanate to a part of carboxylic acid to which glycidyl (meth) acrylate or glycidyl allyl ether is added;
N-vinylamide disclosed in JP-293237 /
(Meth) acrylic acid / alkyl methacrylic acid copolymer partially added with glycidyl (meth) acrylate; polybutadiene compound disclosed in JP-A-62-291638 / (meth) acrylic acid / ( Alkyl methacrylate / styrene copolymers: polyvinyl formal and polyvinyl butyral disclosed in JP-A-62-28829 Added to the side chain disclosed in JP-A-59-53835. A polymer comprising an acryloyl group-containing diol, a polyfunctional carboxylic acid and a polyepoxy compound disclosed in JP-A-61-159416; German Patent No. 3604
A polymer having an amino group and an ethylenically unsaturated double bond group in a side chain disclosed in JP-A No. 4023-1840;
And hydroxyalkyl (meth) acrylates disclosed in JP-A-53-2919 and JP-A-53-37391.
(Meth) acrylic acid copolymer reacted with toluene diisocyanate / 2-hydroxyethyl (meth) acrylate = 1/1 mole adduct; maleic acid monoester disclosed in JP-A-52-47888 / Hydroxyalkyl (meth) acrylate copolymer reacted with toluene diisocyanate / 2-hydroxyethyl (meth) acrylate = 1/1 mole adduct; vinyl methacrylate / methacrylic acid copolymer; and the like.
In addition, the above-mentioned polymer having an acid group in the side chain is prepared by neutralizing the acid group with an alkali such as sodium hydroxide, potassium hydroxide, ammonium, an organic amine or sodium carbonate to form a salt. Alternatively, it can be used as a water-swellable polymer. Among these polymers having an ethylenically unsaturated double bond group in the side chain, particularly useful are those having a carboxylic acid group or a base thereof in the side chain, and the carboxylic acid content before neutralization is an acid. Value is 10-400, preferably 50-200
belongs to. The molecular weight of these polymers is from 10,000
500,000 is suitable, more preferably 20,000 to 200,000.

At least one of which is optionally used in the present invention.
Examples of the photopolymerizable monomer or oligomer having an ethylenically unsaturated double bond group include monofunctional acrylates such as polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, and phenoxyethyl (meth) acrylate. And methacrylate; polyethylene glycol di (meth) acrylate, trimethylolethanetri (meth) acrylate,
Neopentyl glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (acryloyloxypropyl) ) After adding ethylene oxide and propylene oxide to polyfunctional alcohols such as ether, tri (acryloyloxyethyl) isocyanurate, calcium (meth) acrylate, barium (meth) acrylate, glycerin and trimethylolethane (meth) Acrylate, Tokumaki Akira
Urethane acrylates as disclosed in JP-A-48-41708, JP-B-50-6034 and JP-A-51-37193.
JP-A-48-64183, JP-B-49-43191, JP-B-52-30
No. 490, polyester acrylates, polyfunctional acrylates and methacrylates such as epoxy acrylates obtained by reacting epoxy resin with (meth) acrylic acid, and N-methylol acrylamide derivatives disclosed in US Pat. No. 4,540,649. Can be given.
Further, those introduced as photocurable monomers and oligomers in the Adhesion Society of Japan, Vol. 20, No. 7, pages 300 to 308 can also be used.

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

As the photopolymerization initiator used in the present invention, a vicinal polyketaldonyl compound disclosed in U.S. Pat.No. 2,367,660, U.S. Pat.Nos. 2,367,661 and 2,36
Α-carbonyl compound disclosed in 7,670 gazette,
Acyloin ether disclosed in U.S. Pat.No. 2,448,828, aromatic acyloin compound substituted at α-position with a hydrocarbon group disclosed in U.S. Pat.No. 2,722,512, U.S. Pat.Nos. 3,046,127 and 2,951,758 Polynuclear quinone compounds disclosed in US Patent No. 3,549,36
Patent No. 7 discloses a triarylimidazole dimer / p-aminophenyl ketone combination, U.S. Pat.
No. 3,870,524, benzothiazole compounds disclosed in U.S. Pat. No. 4,239,850, benzothiazole compounds / trihalomethyl-s-triazine compounds and acridine disclosed in U.S. Pat. No. 3,751,259. And phenazine compounds, oxadiazole compounds disclosed in U.S. Pat.No. 4,212,970, U.S. Pat.No. 3,954,475, JP-A-53-133428.
No. 4,189,323, JP-A-60-105667, JP-A-62-58241, and trihalomethyl-s-triazine compounds having a chromophore group disclosed in Japanese Patent Application No. 61-227489. And benzophenone group-containing peroxyester compounds disclosed in JP-A-59-197401 and JP-A-60-76503.

The addition amount of these photopolymerization initiators is 0.1 / 20% by weight, more preferably 1 to 10% by weight, based on the whole photosensitive layer composition.

In addition to the above, it is preferable to further add a thermal polymerization inhibitor, for example, hydroquinone, p-methoxyphenol, 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 and the like are useful, and in some cases, a dye or pigment for coloring the photosensitive layer and a pH indicator as a printing agent are added. You can also.

The photosensitive layer composition as described above is supported, for example, by dissolving it in a suitable solvent alone such as 2-methoxyethanol, 2-methoxyethyl acetate, methanol, ethanol, methyl ethyl ketone, water or a mixed solvent in which these are appropriately combined. provided on the body, the coating amount is suitably in the range of about 0.1 g / m ² ~ about 10 g / m ² in weight after drying, more preferably from 0.5 to 5 g / m ^2.

The silicone rubber layer in the present invention has a SiH group and -CH
シ リ コ ー ン CH— is obtained by crosslinking by an addition reaction with a —CH— group, and the silicone rubber layer thus obtained has a feature that the ink repellency is superior to that of a condensation type. Further, it has excellent adhesion to the photosensitive layer used in the present invention. In the condensation type, curing failure occurs when a carboxylic acid is present in the photosensitive layer, whereas in the addition type, curing sufficiently occurs even when the carboxylic acid is present. Since a carboxylic acid can be present in the photosensitive layer in this manner, the photosensitive layer has a feature that development can be performed with a developer mainly composed of water or alkaline water.

Here, examples of the -CH = CH- group include a substituted or unsubstituted alkenylene group and an alkynylene group having 2 to 10 carbon atoms, and do not include an aromatic -CH = CH- bond.

The silicone rubber of the present invention comprises a polyvalent hydrogenogen organopolysiloxane and two or more —CH ＝ CH per molecule.
-Obtained by reaction with a polysiloxane compound having a bond, preferably (1) 100% by weight of an organopolysiloxane having at least two alkenyl groups (more preferably, vinyl groups) directly bonded to silicon atoms in one molecule Part (2) A composition comprising 0.1 to 1000 parts by weight of an organohydrogenpolysiloxane having at least two SiH bonds in one molecule. (3) A composition comprising 0.00001 to 10 parts by weight of an addition catalyst is cured and crosslinked. Ingredient (1)
The alkenyl group may be at the terminal of the molecular chain or at an intermediate position, and the organic group other than the alkenyl group is a substituted or unsubstituted alkyl group or aryl group. Ingredient (1)
May have a trace amount of hydroxyl groups. Ingredient (2)
Reacts with component (1) to form a silicone rubber,
It also plays a role in providing adhesion to the photosensitive layer. The hydrogen group of the component (2) may be at the terminal of the molecular chain or in the middle, and the organic group other than hydrogen is selected from those similar to the component (1). It is preferable that 60% or more of the organic groups of the components (1) and (2) are methyl groups as a whole from the viewpoint of improving ink repellency. Component (1): The molecular structure of component (2) may be linear, cyclic, or branched, and it is preferable that at least one of the molecular weights exceeds 1,000 in terms of rubber physical properties, and further that component (1) Has a molecular weight of 1,000
Is preferably exceeded.

Examples of the component (1) include α, ω-divinylpolydimethylsiloxane, (methylvinylsiloxane) (dimethylsiloxane) copolymer having methyl groups at both terminals, and the like.
Component (2) includes polydimethylsiloxane having both terminal hydrogen groups, α, ω-dimethylpolymethylhydrogensiloxane, (methylhydrogensiloxane) (dimethylsiloxane) copolymer having both terminal methyl groups, and cyclic polymethylhydrogen. Gensiloxane and the like are exemplified.

The addition catalyst of the component (3) is arbitrarily selected from known catalysts, and is particularly preferably a platinum compound, such as platinum alone, platinum chloride, chloroplatinic acid, and olefin-coordinated platinum. In order to control the curing rate of these compositions, organopolysiloxanes having a vinyl group content such as tetracyclo (methylvinyl) siloxane, alcohols containing a carbon-carbon triple bond, acetone, methyl ethyl ketone, methanol, ethanol, propylene glycol monomethyl It is also possible to add a crosslinking inhibitor such as ether.

These compositions have the characteristic that, when the three components are mixed, an addition reaction occurs and curing starts, but the curing rate increases rapidly as the reaction temperature increases. Therefore, for the purpose of extending the pot life until rubberization of the composition, and shortening the curing time on the photosensitive layer, the curing conditions of the composition, the substrate, temperature conditions within the range that the characteristics of the photosensitive layer does not change,
Further, it is preferable to keep the temperature at a high temperature until it is completely cured, from the viewpoint of the stability of the adhesive force with the photosensitive layer.

In addition to these compositions, a known adhesion-imparting agent such as alkenyl real silane may be added, or a hydroxyl group-containing organopolysiloxane or a hydrolyzable functional group-containing silane (or siloxane) which is a composition of a condensation type silicone rubber. ) Is optional, and a known filler such as silica is optionally added for the purpose of improving rubber strength.

The silicone rubber layer in the present invention is to be a printing ink repellent layer. If the thickness is small, there are problems such as a decrease in ink repellency and easy damage, and if the thickness is large, the developability is deteriorated. From the point, the thickness is 0.5
Microns to 5 microns are preferred.

On the photosensitive lithographic printing plate requiring no fountain solution described herein, it is optional to further coat various silicone rubber layers on the silicone rubber layer having the features of the present invention. It is also optional to provide an adhesive layer between the photosensitive layer and the silicone rubber layer for the purpose of increasing the adhesive force between the layers or preventing the catalyst in the silicone rubber composition from being poisoned. To protect the surface of the silicone rubber layer, a transparent film,
For example, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyethylene terephthalate, cellophane, or the like may be laminated, or a polymer coating may be applied.

The photosensitive lithographic printing plate requiring no fountain solution according to the present invention is a developer capable of dissolving or swelling the photosensitive layer in the image area (unexposed area) after being exposed through the transparent original, or a developer capable of swelling the silicone rubber layer. Developed. In this case, there are cases where the photosensitive layer in the image area and the silicone rubber layer thereon are removed, and cases where only the silicone rubber layer in the image area is removed. This can be controlled by the strength of the developer.

As the developer used in the present invention, those known as developers for photosensitive lithographic printing plates requiring no dampening solution can be used. For example, aliphatic hydrocarbons (hexane, heptane, "ISOPAR E, H, G" (trade name of aliphatic hydrocarbons manufactured by Esso Chemical Co., Ltd.) or gasoline, kerosene, etc.), aromatic hydrocarbons (toluene, Xylene, etc.) or halogenated hydrocarbons (trichlene, etc.) to which the following polar solvents are added are preferred.

・ Alcohols (methanol, ethanol, benzyl alcohol, etc.) ・ Ethers (methyl cellosolve, ethyl cellosolve,
Butyl cellosolve, methyl carbitol, ethyl carbitol, butyl carbitol, dioxane, etc. ・ Ketones (acetone, methyl ethyl ketone, etc.) ・ Esters (ethyl acetate, methyl cellosolve acetate, cellosolve acetate, carbitol acetate, etc.) and the above organic solvent system Addition of water to the developer, or those obtained by solubilizing the organic solvent in water using a surfactant or the like,
Further, an alkali agent such as sodium carbonate, monoethanolamine, diethanolamine, triethanolamine, sodium silicate, potassium silicate, sodium hydroxide, potassium hydroxide, sodium borate, or the like is further added thereto. Simply tap water or alkaline water can be used as the developer.

Further, a dye such as crystal violet or Astrazone Red can be added to the developer to simultaneously develop and dye the image area.

The development can be carried out by a known method, for example, by rubbing the plate surface with a developing pad containing the above-described developing solution, or by rubbing the developing solution onto the plate surface and then developing it in water with a developing brush. This removes the silicone rubber layer and photosensitive layer in the image area, exposing the surface of the substrate or primer layer,
That portion becomes the ink receiving portion, or only the silicone rubber layer in the image portion is removed to expose the photosensitive layer, and that portion becomes the ink receiving portion.

〔The invention's effect〕

The fountain solution unnecessary photosensitive lithographic printing plate according to the present invention has a layer structure in which a photosensitive layer and a silicone rubber layer that performs crosslinking by an addition reaction are laminated in this order on a substrate, and as the photosensitive layer,
Having an ethylenically unsaturated double bond group in the side chain, water is a polymer soluble in alkaline water, a monomer or oligomer having an ethylenically unsaturated double bond group if necessary, and a photopolymerization initiator. Since the composition of the present invention is used, the adhesiveness to the silicone rubber layer is excellent, and the change in the adhesive force is small even with the lapse of time.

Next, the present invention will be described with reference to examples, but the present invention is not limited to these examples.

Example 1 The following primer layer composition was applied on a 0.3 mm-thick smooth aluminum plate degreased by an ordinary method so as to have a dry weight of 8.0 g / m ² , heated at 120 ° C. for 2 minutes, and dried and hardened. Film.

Milk casein 98 parts by weight Glyoxal solution 2 parts by weight (40% aqueous solution, Wako Pure Chemical Industries, Ltd.) γ-glycidoxypropyltri (β-methoxyethoxy) silane 3 parts by weight Potassium hydroxide 4 parts by weight Pure water 2000 parts by weight The aluminum plate provided with the primer layer was immersed in a dyeing solution having the following composition for 1 minute, dyed, washed with water, and dried at room temperature.

2000 parts by weight of pure water The following photosensitive composition was applied on an aluminum plate provided with the dyed primer layer so as to have a dry weight of 1 g / m ² and dried at 100 ° C. for 1 minute.

Vinyl methacrylate / methacrylic acid = 80/20 mol% copolymer 2 parts by weight (average molecular weight 210,000) Leuco Crystal Violet 0.02 parts by weight Defensor MCF323 0.02 parts by weight (manufactured by Dainippon Ink and Chemicals, Inc.) Next, the following silicone rubber composition was applied on the above-mentioned photosensitive layer so as to have a dry weight of 2.0 g / m ^2, and was heated at 140 ° C. for 2 minutes. After drying, a cured silicone rubber layer was obtained.

α, ω-divinylpolydimethylsiloxane (average molecular weight 300,000) 90 parts by weight α, ω-dimethylpolymethylhydrogenpolysiloxane 6 parts by weight (average molecular weight 2,500) KF410 (manufactured by Shin-Etsu Chemical Co., Ltd .: α-methylstyrene-modified dimethyl) Siloxane 0.5 parts by weight Olefin-chloroplatinic acid (10% toluene solution) 20 parts by weight Inhibitor (10% toluene solution) 10 parts by weight Isopar G (manufactured by Esso Chemical Co., Ltd.) 1400 parts by weight Toluene 210 parts by weight As described above A 7 μm thick single-sided matted polyethylene terephthalate film was laminated on the surface of the obtained silicone rubber layer to obtain a photosensitive lithographic printing plate requiring no dampening water.

A positive film is layered on this printing plate and adhered in vacuum. Nuark FT26V UDNS ULTRA-PLUS FLIP-TOP PLATE MAK
After exposing to 30 counts by ER, the laminate film was peeled off, immersed in a developer consisting of 8 parts by weight of benzyl alcohol, 3 parts by weight of sodium isopropylnaphthalenesulfonate, 1 part by weight of sodium carbonate and 88 parts by weight of water for 1 minute, and a developing pad Rubbed lightly to remove the unexposed portions of the photosensitive layer and the silicone rubber layer. In this manner, a fountain solution-free lithographic printing plate was obtained in which the image of the positive film was faithfully reproduced over the entire surface of the printing plate.

Toyo Ink's TOYO KING ULTRA TUK was used on this Heidelberg GTO printing press with the dampening water supply removed.
When printing was performed using AQUALES G black ink, a printed material showing faithful image reproducibility was obtained.

Example 2 A 30μ aluminum foil was bonded to both sides of a 200μ polyethylene terephthalate film using an adhesive,
The following primer layer composition was applied on the substrate so as to have a dry weight of 2.0 g / m ² and heated at 120 ° C. for 2 minutes to dry and harden.

Photographic gelatin 680 100 parts by weight (Nitta Gelatin Co., Ltd.) N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane 7 parts by weight TiO ₂ : 30 wt% / gelatin for photography 680: 3 wt% / pure water: 67 wt% Dispersion 20 parts by weight Tartrazine (yellow dye) 2 Parts by weight 4000 parts by weight of pure water After drying, the film was aged at room temperature of about 20 ° C. for 4 days to stabilize the hardened film.

On the substrate coated with the above primer layer, apply the following photosensitive composition to a dry weight of 1.0 g / m ² at 100 ° C.
Dried for 1 minute.

0.62 parts by weight of epoxy ester 3002A Bromphenol blue 0.1 part by weight Methanol silica sol (methanol 30 wt%) (manufactured by Nissan Chemical Industries, Ltd.) 1 part by weight Ethylene glycol monomethyl ether 25 parts by weight Methyl ethyl ketone 35 parts by weight Next, the silicone rubber composition is dried on the photosensitive layer. It was applied so as to have a weight of 1.0 g / m ² and dried at 140 ° C. for 2 minutes to obtain a cured silicone rubber layer.

α, ω-divinylpolydimethylsiloxane (average molecular weight 300,000) 90 parts by weight Methylhydrogenpolysiloxane (average molecular weight 2,500) 3 parts by weight KF410 (manufactured by Shin-Etsu Chemical Co., Ltd .: α-methylstyrene-modified dimethylsiloxane) 0.5 part by weight Olefin -Chloroplatinic acid (10% toluene solution) 20 parts by weight Ethanol 10 parts by weight Isopar G 1400 parts by weight (manufactured by Esso Chemical Co., Ltd.) Polyethylene terephthalate having a thickness of 7 μm is formed on the surface of the silicone rubber layer obtained as described above. The film was laminated and a lithographic printing plate requiring no dampening water was obtained.

Exposure was performed 100 times from a distance of 1 m with a printer FT26V2UPNS (light source: 2KW metal halide lamp) manufactured by Nuark, USA. After the image exposure, the laminate film was peeled off, immersed in an aqueous developer having the following composition for 1 minute, and then rubbed with a developing pad for 1 to 2 minutes while applying running water. The layer was removed.

Benzyl alcohol 8 parts by weight Perex KBL 7.5 parts by weight (38% aqueous solution of anionic surfactant manufactured by Kao Atlas) Water 84.5 parts by weight The obtained lithographic printing plate not requiring dampening solution was rubbed with the following dyeing solution. Only the exposed part of a certain primer layer was stained with a clear purple color.

Crystal violet 1 part by weight Water 99 parts by weight The printing plate thus obtained was printed in the same manner as in Example 1 to obtain a printed matter showing faithful image reproducibility.

Example 3 A photosensitive primer solution having the following composition was applied on a degreased smooth aluminum plate having a thickness of 0.3 mm.
Dry for 1 minute. The coating weight after drying was 4 g / m ² .

Epicoat 1255-HX-30 (30% solution) 5 parts by weight Takenate D-110N (75% solution) 1.5 parts by weight Trimethylolpropane triacrylate 1 part by weight Defensor MCF323 0.02 part by weight (manufactured by Dainippon Ink and Chemicals, Inc.) Benzanthrone 0.2 part by weight methyl ethyl ketone 30 parts by weight propylene glycol monomethyl ether acetate 30 parts by weight Next, the following composition Was prepared, applied on the primer layer, and dried at 100 ° C. for 1 minute. The dry coating weight was 1.0 g / m ^2.

Pentaerythritol triacrylate 0.7 parts by weight 7.5% by weight of a 20% aqueous solution of a polymer having a methacryloyl group and a carboxylate group in the side chain of Synthesis Example 1 2.0 parts by weight Eslex W-201 2.0 parts by weight (manufactured by Sekisui Plastics Co., Ltd.) : Water-soluble polyvinyl acetal resin) (25% aqueous solution) CH ₂ = CHSi (OCH ₂ CH ₂ OOCH ₃ ) ₃ 0.1 part by weight Methanol silica (30% dispersion) 1 part by weight Water 25 parts by weight Methanol 15 parts by weight The silicone solution used in Example 2 was applied on the photosensitive layer and dried at 140 ° C. for 2 minutes. The dry coating weight is 1.0g /
It was m ^2.

A 7 μm thick polyethylene terephthalate film was laminated on the plate prepared as described above to obtain a photosensitive lithographic printing plate requiring no dampening water.

This printing plate was exposed to a Fuji PS step guide in the same manner as in Example 1. After exposure, remove the cover film and
The plate was immersed in warm water of 30 ° C. for 30 seconds and rubbed with a sponge for 30 seconds to remove the unexposed portions of the silicone layer and the photosensitive layer. Thereafter, only the unexposed portion of the primer layer was dyed with the following dyeing solution to obtain a lithographic printing plate requiring no dampening solution and excellent in tone reproducibility.

Benzyl alcohol 5 parts by weight Water 95 parts by weight Victoria Pure Blue BOH 2 parts by weight Nonionic surfactant 2 parts by weight Synthesis Example 1: Methyl methacrylate / acrylonitrile / methacrylic acid = 50/20/30% by weight copolymer (molecular weight 2, 3) 10,000) 100g
Was dissolved in methyl ethyl ketone 200, 30 g of glycidyl methacrylate and 3 g of triethylamine were added, and
The reaction was performed at 8 ° C. for 8 hours. After the reaction, methanol was added to dilute the mixture, which was then poured into water to precipitate a polymer. Thereafter, it was further washed with water and dried under vacuum. The reaction rate determined from the acid value measurement was 68%. 100 g of this polymer was treated with methyl cellosolve 34.
After dissolving in 3g, 10% by weight aqueous sodium hydroxide solution
47 g was added and neutralized to obtain a 20% by weight polymer solution.

Claims (1)

(57) [Claims] 1. A substrate, a photosensitive layer provided on the substrate, and a photosensitive layer provided on the photosensitive layer. A fountain solution-free photosensitive lithographic printing plate comprising a silicone rubber layer which is cross-linked by an addition reaction of -CH = CH- with the -CH = CH- group. A polymer having an ethylenically unsaturated double bond group and being soluble or swellable in water or alkaline water and capable of forming a film; (ii) optionally, at least one photopolymerizable ethylenic polymer A lithographic printing plate requiring no fountain solution, comprising: a monomer or oligomer having an unsaturated double bond; and (iii) a photopolymerization initiator.