WO2009093513A1 - Photosensitive lithographic printing plate and printing method - Google Patents

Abstract

Provided are: a photosensitive lithographic printing plate excellent in printing durability and reduced in scumming in nonimage areas; and a method of printing with the photosensitive lithographic printing plate. The photosensitive lithographic printing plate is characterized by being obtained by subjecting a photosensitive lithographic printing plate material comprising a substrate and, formed thereon, a photosensitive layer comprising a spectral sensitizer, a polymerization initiator, a polymerizable monomer, and a polymeric binder to image exposure and subsequently treating the material with an aqueous solution which contains a water-soluble resin, a surfactant, and a compound represented by the following general formula (1) and has a pH of 3.0-9.0.

Description

Photosensitive planographic printing plate and printing method

The present invention relates to a photosensitive lithographic printing plate obtained from a photosensitive lithographic printing plate material having a photosensitive layer containing a spectral sensitizer, a polymerization initiator, a polymerizable monomer and a polymer binder on a support, and the photosensitive lithographic printing plate. The present invention relates to a printing method using a sex lithographic printing plate.

In general, a photosensitive lithographic printing plate comprises an oleophilic image portion that receives ink in the printing process and a hydrophilic non-image portion that receives dampening water. Lithographic printing utilizes the property that water and printing ink repel each other, so that the oleophilic image area of the photosensitive lithographic printing plate is moistened with the ink receiving area and the hydrophilic non-image area is moistened with the water receiving area (ink non-accepting area). Part), a difference in ink adhesion is caused on the surface of the photosensitive lithographic printing plate, the ink is applied only to the image part, and then the ink is transferred to a printing medium such as paper and printed. .

In order to produce this photosensitive lithographic printing plate, a lithographic printing plate precursor (PS plate) in which an oleophilic photosensitive resin layer (image recording layer) is provided on a hydrophilic support has been widely used. . Usually, after exposing the photosensitive lithographic printing plate precursor through an original image such as a lithographic film, the portion to be an image portion of the image recording layer is left, and other unnecessary image recording layers are removed with an alkaline developer or Photosensitive lithographic printing plate is obtained by dissolving and removing with an organic solvent and exposing the surface of the hydrophilic support to form a non-image area.

In the conventional plate making process of a photosensitive lithographic printing plate precursor, after exposure, a process of dissolving and removing unnecessary image recording layers with a developer or the like is necessary. However, development closer to the neutral range is necessary for environmental and safety reasons. Treatment with liquid and less waste liquid are cited as problems. Particularly in recent years, disposal of waste liquid discharged with wet processing has become a major concern for the entire industry due to consideration of the global environment, and thus the demand for solving the above problems has become stronger.

On the other hand, in recent years, digitization technology for electronically processing, storing, and outputting image information by a computer has become widespread, and various new image output methods corresponding to such digitization technology will be put into practical use. It is becoming. Along with this, digitized image information is carried by high-convergence radiation such as laser light, and the photosensitive lithographic printing plate precursor is scanned and exposed with the light, and directly exposed without passing through a lithographic film. Computer-to-plate technology for producing sex lithographic printing plates has attracted attention. Therefore, obtaining a photosensitive lithographic printing plate precursor adapted to such a technique is one of the important technical issues.

As mentioned above, the low alkali level of the developer and the simplification of the processing process are more strongly desired than ever in terms of consideration for the global environment and the adaptation to a small space and low running cost. It has become to. However, as described above, the development processing step generally comprises three steps: development with an alkaline aqueous solution having a pH of 10 or more, followed by washing with an alkaline agent in a washing bath and then processing with a gum solution mainly composed of a hydrophilic resin. ing. For this reason, the automatic developing machine itself takes up a large space, and developing waste liquid, washing waste liquid, and gum waste liquid are produced, leaving problems in terms of environment and running cost.

On the other hand, a photosensitive lithographic printing plate precursor having an image forming layer containing a polymerizable compound, a polymerization initiator, and a hydrophobic binder polymer on a support, a pH 3 containing a surfactant and a water-soluble polymer. Techniques for obtaining photosensitive lithographic printing plates with the developing solutions 1 to 9 (see, for example, Patent Documents 1 to 8) are known.

However, in these technologies, there are still problems with respect to printing durability and further stains on non-image areas.
JP 2006-39339 A JP 2006-309160 A JP 2007-34215 A JP 2007-52279 A JP 2007-58170 A JP 2007-79136 A JP 2007-79202 A JP 2007-79540 A

An object of the present invention is to provide a photosensitive lithographic printing plate having excellent printing durability and improved non-image area stains, and a printing method using the photosensitive lithographic printing plate.

The above object of the present invention is achieved by the following configuration.

1. After image exposure of a photosensitive lithographic printing plate material having a photosensitive layer containing a spectral sensitizer, a polymerization initiator, a polymerizable monomer and a polymer binder on a support, a water-soluble resin, a surfactant and the following general formula A photosensitive lithographic printing plate obtained by treatment with an aqueous solution having a pH of 3.0 to 9.0 containing the compound represented by (1).

(In the formula, A ₁ represents an alkyl group having 1 to 5 carbon atoms, an aryl group, or — (CH ₂ ) _n COOM. M, M ₁ , M ₂ , and M ₃ are each independently a hydrogen atom, an alkali metal, or ammonium. Represents a group, n represents 0, 1 or 2)
2. 2. The photosensitive lithographic printing plate as described in 1 above, wherein the content of the compound represented by the general formula (1) is 0.01 to 1.0% by mass.

3. 3. The photosensitive lithographic printing plate as described in 1 or 2 above, wherein a hexaarylbisimidazole compound is used as the polymerization initiator.

4. 4. A printing method comprising printing the photosensitive lithographic printing plate according to any one of 1 to 3 by applying dampening water and printing ink.

According to the present invention, it was possible to provide a photosensitive lithographic printing plate having excellent printing durability and improved non-image area contamination, and a printing method using the photosensitive lithographic printing plate.

Hereinafter, the present invention will be described in detail.

(Aqueous solution that removes unexposed areas of the image)
In the production of the photosensitive lithographic printing plate of the present invention, an unexposed portion (non-image portion) after exposing and recording image information is represented by a water-soluble resin, a surfactant, and the general formula (1). It is characterized in that it can be removed with an aqueous solution containing the compound and having a pH in the range of 3.0 to 9.0. The temperature of the aqueous solution is preferably room temperature.

Examples of the water-soluble resin according to the present invention include gum arabic, fiber derivatives (for example, carboxymethylcellulose, carboxyethylcellulose, methylcellulose and the like) and modified products thereof, polyvinyl alcohol and derivatives thereof, polyvinylpyrrolidone, polyacrylamide and copolymers thereof. Vinyl methyl ether / maleic anhydride copolymer, vinyl acetate / maleic anhydride copolymer, styrene / maleic anhydride copolymer, and the like. The content of these water-soluble resins is suitably 0.1 to 50% by mass, more preferably 0.5 to 3.0% by mass in the composition.

In addition, examples of the surfactant according to the present invention include an anionic surfactant and a nonionic surfactant.

For example, anionic surfactants include fatty acid salts, abietic acid salts, hydroxyalkane sulfonates, alkane sulfonates, dialkyl sulfosuccinates, linear alkyl benzene sulfonates, branched alkyl benzene sulfonates, alkyl naphthalene sulfones. Acid salts, alkylphenoxy polyoxyethylene propyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, polyoxyethylene aryl ether sulfonates, polyoxyethylene naphthyl ether sulfonates, N-methyl-N-oleyl taurine sodium salts , N-alkylsulfosuccinic acid monoamido disodium salts, petroleum sulfonates, nitrated castor oil, sulfated beef tallow oil, sulfate esters of fatty acid alkyl esters Alkyl nitrates, polyoxyethylene alkyl ether sulfates, fatty acid monoglyceride sulfates, polyoxyethylene alkylphenyl ether sulfates, polyoxyethylene styryl phenyl ether sulfates, alkyl phosphate esters, polyoxyethylene alkyl ethers Phosphoric acid ester salts, polyoxyethylene alkylphenyl ether phosphoric acid ester salts, partially saponified products of styrene-maleic anhydride copolymer, partially saponified products of olefin-maleic anhydride copolymer, naphthalene sulfonate formalin condensates Etc.

Among these, dialkyl sulfosuccinates, alkyl sulfate esters, and alkyl naphthalene sulfonates are particularly preferably used.

Nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene aryl ethers, polyoxyethylene naphthyl ether, polyoxyethylene polystyryl phenyl ether, polyoxyethylene polyoxy Propylene alkyl ether, glycerin fatty acid partial ester, sorbitan fatty acid partial ester, pentaerythritol fatty acid partial ester, propylene glycol mono fatty acid ester, sucrose fatty acid partial ester, polyoxyethylene sorbitan fatty acid partial ester, polyoxyethylene sorbitol fatty acid moiety Esters, polyethylene glycol fatty acid esters, polyglycerin fatty acid partial esters, polyoxyethylene Castor oils, polyoxyethylene glycerin fatty acid partial esters, fatty acid diethanolamides, N, N-bis-2-hydroxyalkylamines, polyoxyethylene alkylamines, triethanolamine fatty acid esters, trialkylamine oxides, etc. It is done.

Of these, polyoxyethylene alkylphenyl ethers, polyoxyethylene polyexoxypropylene alkyl ether, polyoxyethylene-polyoxypropylene block polymers and the like are preferably used. Fluorine-based and silicon-based anions and nonionic surfactants can also be used in the same manner.

Examples of preferred surfactants include surfactants added to the lithographic printing plate surface protective agents described in JP-A Nos. 2004-167903, 2004-230650, and 2005-43393. .

These surfactants can be used in combination of two or more. For example, two or more different types can be used in combination. For example, a combination of two or more different anionic surfactants or a combination of an anionic surfactant and a nonionic surfactant is preferable. The amount of the surfactant used is not particularly limited, but is preferably 0.01 to 20% by mass of the post-treatment liquid.

The pH of the aqueous solution according to the present invention can be used in the range of 3.0 to 9.0. When used in the acidic range of pH 3 to 6, it is adjusted by adding a mineral acid, organic acid or inorganic salt to the aqueous solution. The addition amount is preferably 0.01 to 2% by mass. Examples of mineral acids include nitric acid, sulfuric acid, phosphoric acid, and metaphosphoric acid.

Also, examples of the organic acid include citric acid, acetic acid, succinic acid, malonic acid, p-toluenesulfonic acid, tartaric acid, malic acid, lactic acid, levulinic acid, phytic acid, and organic phosphonic acid.

Furthermore, examples of the inorganic salt include magnesium nitrate, primary sodium phosphate, secondary sodium phosphate, nickel sulfate, sodium hexamethanoate, sodium tripolyphosphate, and the like. You may use together at least 1 sort (s) or 2 or more types, such as a mineral acid, an organic acid, or an inorganic salt.

When used in the basic region pH 8 to 9, a water-soluble organic base or inorganic base can be added to adjust the pH. Preferable is a water-soluble organic base, and examples thereof include triethanolamine, diethanolamine, and ethanolamine.

In addition, a preservative, an antifoaming agent, and the like can be added to the aqueous solution according to the present invention.

Examples of preservatives include phenol or derivatives thereof, o-phenylphenol, p-chlorometacresol, hydroxybenzoic acid alkyl ester, formalin, imidazole derivatives, sodium dehydroacetate, 4-isothiazolin-3-one derivatives, benzoisothiazoline- Examples include 3-one, benztriazole derivatives, amiding anidine derivatives, quaternary ammonium salts, pyridine, quinoline, guanidine and other derivatives, diazine, triazole derivatives, oxazole and oxazine derivatives.

A preferable addition amount is an amount that exerts a stable effect on bacteria, molds, yeasts, etc., and varies depending on the types of bacteria, molds, yeasts, etc., but 0.01 to The range of 4% by mass is preferable, and it is preferable to use two or more kinds of preservatives together so as to be effective against various molds and sterilization.

Further, as the antifoaming agent, a silicon antifoaming agent is preferable. Among them, emulsification dispersion type and solubilization can be used. The range of 0.01 to 1.0% by mass is optimal.

Furthermore, in this invention, the chelate compound represented by the said General formula (1) is contained. In the general formula (1), an alkyl group having 1 to 5 carbon atoms A ₁ represents an aryl group may have a substituent. As the substituent, a hydroxyl group is preferable. The alkali metal represented by M, M ₁ , M ₂ , or M ₃ is preferably sodium or potassium.

By using the chelate compound represented by the general formula (1), compared to an aqueous solution that removes an unexposed image portion containing a known chelate compound, it has a remarkable effect on printing durability and stain on the non-image area. Demonstrate. The content of the compound represented by the general formula (1) in an aqueous solution for removing an unexposed image portion is preferably 0.01 to 1.0% by mass.

Preferred specific examples of the compound represented by the general formula (1) are listed below, but are not limited thereto.

A well-known chelate compound can be used with the chelate compound represented by General formula (1). For example, ethylenediaminetetraacetic acid, its potassium salt, its sodium salt; diethylenetriaminepentaacetic acid, its potassium salt, its sodium salt; triethylenetetramine hexaacetic acid, its sodium salt; ethylenediamine disuccinic acid, its potassium salt, its sodium salt; Ethylenetetraminehexaacetic acid, potassium salt thereof, sodium salt thereof, hydroxyethylethylenediaminetriacetic acid, potassium salt thereof, sodium salt thereof: nitrilotriacetic acid, sodium salt thereof; 1-hydroxyethane-1,1-diphosphonic acid, potassium salt thereof, Examples thereof include organic phosphonic acids or phosphonoalkanetricarboxylic acids such as amino salts (aminotri (methylenephosphonic acid), potassium salts, sodium salts, and the like).

An organic amine salt is also effective in place of the sodium salt and potassium salt of the chelating agent. The addition amount is suitably 0.001 to 1.0% by mass.

In addition to the above components, a sensitizer can be added if necessary. For example, hydrocarbons such as turpentine oil, xylene, toluene, low heptane, solvent naphtha, kerosene, mineral spirit, petroleum fraction having a boiling point of about 120 ° C. to about 250 ° C., for example, dibutyl phthalate, dihebutyl phthalate, di-n Phthalic acid diester agents such as octyl phthalate, di (2-ethylhexyl) phthalate, dinonyl phthalate, didecyl phthalate, dilauryl phthalate, butyl benzyl phthalate, eg dioctyl adipate, butyl glycol adipate, dioctyl azelate, dibutyl sebacate Aliphatic dibasic acid esters such as di (2-ethylhexyl) sebacate and dioctyl sebacate, for example, epoxidized triglycerides such as epoxidized soybean oil, such as tricresyl phosphate, trio Includes plasticizers having freezing points of 15 ° C or lower and boiling points of 300 ° C or higher at 1 atm, such as phosphoric esters such as tylyphosphate and trischlorethyl phosphate, for example, benzoic esters such as benzyl benzoate It is.

In addition, caproic acid, enanthic acid, caprylic acid, helargonic acid, capric acid, undecyl acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachic acid, behenic acid, lignoserine Saturated fatty acids such as acid, serotic acid, heptacosanoic acid, montanic acid, melicinic acid, lactelic acid, isovaleric acid, and acrylic acid, crotonic acid, isocrotonic acid, undecylenic acid, oleic acid, elaidic acid, celetic acid, nillic acid, buteticidin Examples also include unsaturated fatty acids such as acid, sorbic acid, linoleic acid, linolenic acid, arachidonic acid, propiolic acid, stearolic acid, sardine acid, talylic acid and licanoic acid.

More preferably, the fatty acid is liquid at 50 ° C., more preferably 5 to 25 carbon atoms, and most preferably 8 to 21 carbon atoms. These sensitizers can be used alone or in combination of two or more. A preferable range of the amount used is 0.01 to 10% by mass, and a more preferable range is 0.05 to 5% by mass.

(Polymerizable monomer)
The polymerizable monomer is a compound (monomer) that can be polymerized with the product of the reaction of the polymerization initiator by image exposure as a trigger. As the polymerizable monomer according to the present invention, a wide range of compounds that can start a polymerization reaction triggered by a reaction with a radical species generated from the polymerization initiator according to the present invention can be used.

As the polymerizable monomer according to the present invention, an ethylenically unsaturated bond-containing compound is preferably used and is a polymerizable compound, and is generally used for general radical polymerizable monomers and ultraviolet curable resins. Polyfunctional monomers having a plurality of addition-polymerizable ethylenic double bonds in the molecule and polyfunctional oligomers.

The polymerizable monomer according to the present invention is not limited, but preferable examples thereof include 2-ethylhexyl acrylate, 2-hydroxypropyl acrylate, glycerol acrylate, tetrahydrofurfuryl acrylate, phenoxyethyl acrylate, nonylphenoxyethyl acrylate, tetrahydrofurfuryl. Monofunctional acrylic acid esters such as oxyethyl acrylate, tetrahydrofurfuryloxyhexanolide acrylate, acrylate of ε-caprolactone adduct of 1,3-dioxane alcohol, 1,3-dioxolane acrylate, or methacrylates of these acrylates, Methacrylic acid, itaconic acid, crotonic acid, maleic acid ester instead of itaconate, crotonate, maleate, Diglycol diacrylate, triethylene glycol diacrylate, pentaerythritol diacrylate, hydroquinone diacrylate, resorcin diacrylate, hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, neopentyl glycol hydroxypivalate Acrylate, dipentyl neopentyl glycol adipate, diacrylate of ε-caprolactone adduct of neopentyl glycol hydroxypivalate, 2- (2-hydroxy-1,1-dimethylethyl) -5-hydroxymethyl-5-ethyl- Ε of 1,3-dioxane diacrylate, tricyclodecane dimethylol acrylate, tricyclodecane dimethylol acrylate Caprolactone adducts, bifunctional acrylic esters such as diacrylate of diglycidyl ether of 1,6-hexanediol, or methacrylic acid, itaconic acid, crotonic acid in which these acrylates are replaced with methacrylate, itaconate, crotonate, maleate, Maleic acid esters such as trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, trimethylolethane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexa Acrylates and ε-caprolactone adducts of dipentaerythritol hexaacrylate Pyrogallol triacrylate, propionic acid / dipentaerythritol triacrylate, propionic acid / dipentaerythritol tetraacrylate, hydroxypivalylaldehyde-modified dimethylolpropane triacrylate, etc., or polyfunctional acrylic acid ester acid, or acrylate of these, methacrylate, itaconate, Mention may be made of methacrylic acid, itaconic acid, crotonic acid, maleic acid ester, etc. instead of crotonate and maleate.

Also, prepolymers can be used in the same manner as described above. Examples of the prepolymer include compounds as described below, and a prepolymer obtained by introducing acrylic acid or methacrylic acid into an oligomer having an appropriate molecular weight and imparting photopolymerizability can also be suitably used. These prepolymers may be used alone or in combination of two or more, and may be used by mixing with the above-mentioned monomers and / or oligomers.

Examples of the prepolymer include adipic acid, trimellitic acid, maleic acid, phthalic acid, terephthalic acid, hymic acid, malonic acid, succinic acid, glutaric acid, itaconic acid, pyromellitic acid, fumaric acid, glutaric acid, and pimelic acid. , Polybasic acids such as sebacic acid, dodecanoic acid, tetrahydrophthalic acid, and ethylene glycol, propylene glycol, diethylene glycol, propylene oxide, 1,4-butanediol, triethylene glycol, tetraethylene glycol, polyethylene glycol, glycerin, tri Polyester obtained by introducing (meth) acrylic acid into a polyester obtained by the combination of polyhydric alcohols such as methylolpropane, pentaerythritol, sorbitol, 1,6-hexanediol, 1,2,6-hexanetriol Acrylates such as bisphenol A, epichlorohydrin, (meth) acrylic acid, and epoxy acrylates in which (meth) acrylic acid is introduced into an epoxy resin such as phenol novolac, epichlorohydrin, (meth) acrylic acid, such as ethylene glycol Adipic acid, tolylene diisocyanate, 2-hydroxyethyl acrylate, polyethylene glycol, tolylene diisocyanate, 2-hydroxyethyl acrylate, hydroxyethyl phthalyl methacrylate, xylene diisocyanate, 1,2-polybutadiene glycol, tolylene diisocyanate, 2-hydroxyethyl Acrylate, trimethylolpropane, propylene glycol, tolylene diisocyanate, 2-hydroxyethyl acrylate As described above, urethane acrylates in which (meth) acrylic acid is introduced into urethane resins, for example, silicone resin acrylates such as polysiloxane acrylate, polysiloxane diisocyanate, 2-hydroxyethyl acrylate, and other oil-modified alkyd resins (meth ) Prepolymers such as alkyd-modified acrylates and spirane resin acrylates introduced with acryloyl groups.

The photosensitive layer according to the present invention includes a phosphazene monomer, triethylene glycol, isocyanuric acid EO (ethylene oxide) modified diacrylate, isocyanuric acid EO modified triacrylate, dimethylol tricyclodecane diacrylate, trimethylolpropane benzoic acid benzoic acid. Addition-polymerizable oligomers and prepolymers having monomers such as esters, alkylene glycol type acrylic acid-modified, urethane-modified acrylates, and structural units formed from the monomers can be contained.

Furthermore, examples of the ethylenic monomer that can be used in combination with the present invention include a phosphoric ester compound containing at least one (meth) acryloyl group. The compound is not particularly limited as long as at least a part of the hydroxyl group of phosphoric acid is esterified and has a (meth) acryloyl group.

In addition, JP 58-212994, 61-6649, 62-46688, 62-48589, 62-173295, 62-187092, 63-67189, JP-A 1 -244891 publications, etc., and "11290 Chemical Products", Chemical Industry Daily, p. 286-p. 294, “UV / EB Curing Handbook (raw material)”, Kobunshi Publishing Co., p. The compounds described in 11 to 65 can also be suitably used in the present invention. Of these, compounds having two or more acrylic groups or methacryl groups in the molecule are preferred in the present invention, and those having a molecular weight of 10,000 or less, more preferably 5,000 or less are preferred.

In addition, it is preferable to use an addition-polymerizable ethylenic double bond-containing compound containing a tertiary amino group in the molecule, which is a tertiary amine monomer, in the photosensitive layer according to the present invention. Although there is no particular limitation on the structure, a tertiary amine compound having a hydroxyl group modified with glycidyl methacrylate, methacrylic acid chloride, acrylic acid chloride or the like is preferably used. Specifically, polymerizable compounds described in JP-A-1-165613, 1-203413 and 1-1197213 are preferably used.

Furthermore, in the present invention, a tertiary amine monomer, a polyhydric alcohol containing a tertiary amino group in the molecule, a diisocyanate compound, and a compound containing an ethylenic double bond capable of addition polymerization with a hydroxyl group in the molecule are used. It is preferred to use a reaction product.

Examples of the polyhydric alcohol having a tertiary amino group in the molecule include triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, Nn-butyldiethanolamine, Nt-butyldiethanolamine, N, N-di (hydroxyethyl) aniline, N, N, N ′, N′-tetra-2-hydroxypropylethylenediamine, p-tolyldiethanolamine, N, N, N ′, N′-tetra-2-hydroxyethylethylenediamine, N, N-bis (2-hydroxypropyl) aniline, allyldiethanolamine, 3- (dimethylamino) -1,2-propanediol, 3-diethylamino-1,2-propanediol, N, N-di (n-propyl) ) Amino-2,3-propanediol, N, N-di (i o- propyl) amino-2,3-propanediol, 3- (N-methyl--N- benzylamino) -1,2-propanediol, but not limited thereto.

Diisocyanate compounds include butane-1,4-diisocyanate, hexane-1,6-diisocyanate, 2-methylpentane-1,5-diisocyanate, octane-1,8-diisocyanate, 1,3-diisocyanate methyl-cyclohexanone 2,2,4-trimethylhexane-1,6-diisocyanate, isophorone diisocyanate, 1,2-phenylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene-2,4-diisocyanate, tolylene- Examples include 2,5-diisocyanate, tolylene-2,6-diisocyanate, 1,3-di (isocyanatomethyl) benzene, 1,3-bis (1-isocyanato-1-methylethyl) benzene, and the like. In Not a constant.

Examples of the compound containing a hydroxyl group and addition polymerizable ethylenic double bond in the molecule include 2-hydroxyethyl methacrylate (MH-1), 2-hydroxyethyl acrylate (MH-2), 4-hydroxy Examples thereof include butyl acrylate (MH-4), 2-hydroxypropylene-1,3-dimethacrylate (MH-7), 2-hydroxypropylene-1-methacrylate-3-acrylate (MH-8), and the like.

Specific examples of a polyhydric alcohol containing a tertiary amino group in the molecule, a diisocyanate compound, and a compound containing an ethylenic double bond capable of addition polymerization with a hydroxyl group in the molecule are as follows. As a reaction product. These reactions can be carried out in the same manner as the method of synthesizing urethane acrylate by the reaction of a normal diol compound, diisocyanate compound, and hydroxyl group-containing acrylate compound.

M-1: Reaction product of triethanolamine (1 mol), hexane-1,6-diisocyanate (3 mol), 2-hydroxyethyl methacrylate (3 mol) M-2: Triethanolamine (1 mol), isophorone Reaction product of diisocyanate (3 mol) and 2-hydroxyethyl acrylate (3 mol) M-3: Nn-butyldiethanolamine (1 mol), 1,3-bis (1-isocyanato-1-methylethyl) Reaction product of benzene (2 mol) and 2-hydroxypropylene-1-methacrylate-3-acrylate (2 mol) M-4: Nn-butyldiethanolamine (1 mol), 1,3-di (isocyanatomethyl) ) Reaction of benzene (2 mol), 2-hydroxypropylene-1-methacrylate-3-acrylate (2 mol) The product M-5: N-methyldiethanolamine (1 mole), tolylene-2,4-diisocyanate (2 moles), 2-hydroxypropylene-1,3-dimethacrylate reaction product of (2 moles).

In addition, acrylates or alkyl acrylates described in JP-A-1-105238 and JP-A-2-127404 can be used.

(Polymerization initiator)
The polymerization initiator according to the present invention is capable of initiating polymerization of a polymerizable monomer by image exposure. In the present invention, it is more preferable that the photosensitive layer contains a hexaarylbisimidazole compound as a polymerization initiator.

The process for producing hexaarylbiimidazole (HABI, triaryl-imidazole dimer) compounds used in the present invention is described in West German Patent 1,470,154 and is photopolymerizable. Their use in such compositions is described in European Patent No. 24,629, European Patent No. 107,792, US Pat. No. 4,410,621, European Patent No. 215,453 and German Patent No. 3, It is described in each specification of No. 211,312.

For example, 2,4,5,2 ′, 4 ′, 5′-hexaphenylbiimidazole, 2,2′-bis (2-chlorophenyl) -4,5,4 ′, 5′-tetraphenylbiimidazole, 2 , 2'-bis (2-bromophenyl) -4,5,4 ', 5'-tetraphenylbiimidazole, 2,2'-bis (2,4-dichlorophenyl) -4,5,4', 5 ' -Tetraphenylbiimidazole, 2,2'-bis (2-chlorophenyl) -4,5,4 ', 5'-tetrakis (3-methoxyphenyl) biimidazole, 2,2'-bis (2-chlorophenyl)- 4,5,4 ', 5'-tetrakis (3,4,5-trimethoxyphenyl) -biimidazole, 2,5,2', 5'-tetrakis (2-chlorophenyl) -4,4'-bis ( 3,4-dimethoxyphenyl Biimidazole, 2,2'-bis (2,6-dichlorophenyl) -4,5,4 ', 5'-tetraphenylbiimidazole, 2,2'-bis (2-nitrophenyl) -4,5,4 ', 5'-tetraphenylbiimidazole, 2,2'-di-o-tolyl-4,5,4', 5'-tetraphenylbiimidazole, 2,2'-bis (2-ethoxyphenyl) -4 5,4 ', 5'-tetraphenylbiimidazole and 2,2'-bis (2,6-difluorophenyl) -4,5,4', 5'-tetraphenylbiimidazole.

In the present invention, as a polymerization initiator, other types of polymerization initiators can be used in combination with hexaarylbiimidazole. For example, titanocene compounds, monoalkyltriaryl borate compounds, iron arene complex compounds, and polyhalogen compounds are preferably used.

Examples of titanocene compounds include compounds described in JP-A-63-41483 and JP-A-2-291. More preferred specific examples include bis (cyclopentadienyl) -Ti--. Di-chloride, bis (cyclopentadienyl) -Ti-bis-phenyl, bis (cyclopentadienyl) -Ti-bis-2,3,4,5,6-pentafluorophenyl, bis (cyclopentadienyl) ) -Ti-bis-2,3,5,6-tetrafluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,4,6-trifluorophenyl, bis (cyclopentadienyl) -Ti- Bis-2,6-difluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,4-difluorophenyl, bis (methylcyclopentadienyl) Ti-bis-2,3,4,5,6-pentafluorophenyl, bis (methylcyclopentadienyl) -Ti-bis-2,3,5,6-tetrafluorophenyl, bis (methylcyclopentadienyl) ) -Ti-bis-2,6-difluorophenyl (IRGACURE 727L: manufactured by Ciba Specialty Chemicals), bis (cyclopentadienyl) -bis (2,6-difluoro-3- (py-1-yl) phenyl) Titanium (IRGACURE784: Ciba Specialty Chemicals), bis (cyclopentadienyl) -bis (2,4,6-trifluoro-3- (pyridin-1-yl) phenyl) titanium bis (cyclopentadienyl) -Bis (2,4,6-trifluoro-3- (2-5-dimethylpy-1-yl) phenyl) tita Umm, and the like.

Examples of the monoalkyl triaryl borate compound include compounds described in JP-A Nos. 62-150242 and 62-143044, and more preferable specific examples include tetra-n-butylammonium.n -Butyl-trinaphthalen-1-yl-borate, tetra-n-butylammonium / n-butyl-triphenyl-borate, tetra-n-butylammonium / n-butyl-tri (4-t-butylphenyl) -borate Tetra-n-butylammonium · n-hexyl-tri (3-chloro-4-methylphenyl) -borate, tetra-n-butylammonium · n-hexyl-tri (3-fluorophenyl) -borate and the like. .

Examples of the iron arene complex compound include compounds described in JP-A-59-219307, and more preferable specific examples include η-benzene- (η-cyclopentadienyl) iron hexafluorophosphate, η -Cumene- (η-cyclopentadienyl) iron hexafluorophosphate, η-fluorene- (η-cyclopentadienyl) iron hexafluorophosphate, η-naphthalene- (η-cyclopentadienyl) iron hexafluorophosphate, and η-xylene- (η-cyclopentadienyl) iron hexafluorophosphate, η-benzene- (η-cyclopentadienyl) iron tetrafluoroborate, and the like.

As the polyhalogen compound, a compound having a trihalogenmethyl group, a dihalogenmethyl group or a dihalomethylene group is preferably used, and in particular, a halogen compound represented by the following general formula (PIH1) and the above group is substituted with an oxadiazole ring. A compound is preferably used. Among these, a halogen compound represented by the following general formula (PIH2) is particularly preferably used.

Formula (PIH1) R ¹ —CY ₂ — (C═O) —R ²
In the formula, R ¹ represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, an iminosulfonyl group, or a cyano group. R ² represents a monovalent substituent. R ¹ and R ² may combine to form a ring. Y ₂ represents a halogen atom.

Formula (PIH2) CY ₃ — (C═O) —XR ³
Wherein, R ³ represents a monovalent substituent. X represents —O— or —NR ⁴ —. R ⁴ represents a hydrogen atom or an alkyl group. R ³ and R ⁴ may combine to form a ring. Y ₃ represents a halogen atom. Among these, those having a polyhalogen acetylamide group are particularly preferably used.

In addition, compounds in which a polyhalogen methyl group is substituted with an oxadiazole ring are also preferably used. Further, oxadiazole compounds described in JP-A-5-34904, JP-A-45875, and JP-A-8-240909 are also preferably used.

The biimidazole compound is a derivative of biimidazole, and examples thereof include compounds described in JP-A No. 2003-295426.

Other optional polymerization initiators can be used in combination. For example, J. et al. Carbonyl compounds, organic sulfur compounds, persulfides, redox compounds, azo, diazo compounds, halogen compounds, and photoreductive dyes as described in Chapter 5 of “Light Sensitive Systems” by J. Kosar Etc. More specific compounds are disclosed in GB 1,459,563.

That is, as the polymerization initiator that can be used in combination, the following can be used.

Benzoin derivatives such as benzoin methyl ether, benzoin-i-propyl ether, α, α-dimethoxy-α-phenylacetophenone; benzophenone, 2,4-dichlorobenzophenone, methyl o-benzoylbenzoate, 4,4'-bis (dimethyl) Benzophenone derivatives such as amino) benzophenone; thioxanthone derivatives such as 2-chlorothioxanthone and 2-i-propylthioxanthone; anthraquinone derivatives such as 2-chloroanthraquinone and 2-methylanthraquinone; N-methylacridone, N-butylacridone and the like In addition to α, α-diethoxyacetophenone, benzyl, fluorenone, xanthone, uranyl compounds, JP-B-59-1281, JP-A-61-9621 and JP-A-60-60104 Triazine derivatives described in Japanese Unexamined Patent Publication Nos. 59-15504 and 61-243807; Japanese Patent Publication Nos. 43-23684, 44-6413, 44-6413, 47 -1604 and diazonium compounds described in US Pat. No. 3,567,453; US Pat. Nos. 2,848,328, 2,852,379 and 2,940,853 Organic azide compounds described in the specification; o-quinonediazides described in JP-Bs 36-22062b, 37-13109, 38-18015, and 45-9610; JP-B 55-39162, Various publications described in Japanese Laid-Open Publication Nos. 59-14023 and “Macromolecules”, Vol. 10, page 1307 (1977) Ni compounds; azo compounds described in JP-A-59-142205; JP-A-1-54440, European Patent Nos. 109,851 and 126,712, and “Journal of Imaging Science” (J. Imag. Sci.), Vol. 30, page 174 (1986); (oxo) sulfonium organoboron complexes described in JP-A-5-213891 and JP-A-5-255347; Transition metal complexes containing transition metals such as ruthenium described in "Coordination Chemistry Review" Vol. 84, pp. 85-277 (1988) and JP-A-2-182701; No. 2,4,5-triaryl Imidazole dimer; carbon tetrabromide, organic halogen compounds in JP 59-107344 JP, etc.

The content of the polymerization initiator according to the present invention (total amount of polymerization initiator) is preferably from 0.1 to 20% by mass, particularly preferably from 0.5 to 15% by mass, based on the polymerizable monomer.

(Spectral sensitizer)
The photosensitive layer according to the present invention preferably contains a spectral sensitizer having a maximum absorption wavelength of 350 to 450 nm as a spectral sensitizer.

Examples of the spectral sensitizer include cyanine, merocyanine, porphyrin, spiro compound, ferrocene, fluorene, fulgide, imidazole, perylene, phenazine, phenothiazine, acridine, acridone, azo compound, diphenylmethane, triphenylmethane, triphenylamine, Coumarin derivatives, quinacridone, indigo, styryl, pyrylium compounds, pyromethene compounds, pyrazolotriazole compounds, benzothiazole compounds, barbituric acid derivatives, thiobarbituric acid derivatives, ketoalcohol borate complexes, and the like.

Examples of the coumarin derivative include B-1 to B-22 coumarin derivatives of JP-A-8-129258, D-1 to D-32 coumarin derivatives of JP-A-2003-21901, and JP-A-2002. No. 1-363206 of coumarin derivatives, JP-A No. 2002-363207 No. 1 to 40 coumarin derivatives, JP-A No. 2002-363208 No. 1 to 34 coumarin derivatives, JP-A No. 2002-363209 Examples thereof include 1 to 56 coumarin derivatives and can be preferably used.

Examples of other dyes that can be preferably used include, for example, JP-A Nos. 2000-98605, 2000-147773, 2000-206690, 2000-258910, 2000-309724, 2001-042524, And spectral sensitizers described in JP-A Nos. 2002-202598 and 2000-221790.

(Polymer binder)
The polymer binder according to the present invention is capable of supporting the components contained in the photosensitive layer on a support. Examples of the polymer binder include acrylic polymers, polyvinyl butyral resins, polyurethane resins, polyamide resins, Polyester resin, epoxy resin, phenol resin, polycarbonate resin, polyvinyl butyral resin, polyvinyl formal resin, shellac, and other natural resins can be used. Two or more of these may be used in combination.

Preferably, it is a vinyl copolymer obtained by copolymerization of acrylic monomers. Furthermore, the copolymer composition of the polymer binder is preferably a copolymer of (a) carboxyl group-containing monomer, (b) methacrylic acid alkyl ester, or acrylic acid alkyl ester.

Specific examples of the carboxyl group-containing monomer include α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride and the like. In addition, carboxylic acids such as phthalic acid and 2-hydroxymethacrylate half ester are also preferred.

Specific examples of alkyl methacrylate esters and alkyl methacrylate esters include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate. , Decyl methacrylate, undecyl methacrylate, dodecyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonyl acrylate, acrylic Cyclic alkyl esters such as cyclohexyl methacrylate and cyclohexyl acrylate, in addition to unsubstituted alkyl esters such as decyl acid, undecyl acrylate, and dodecyl acrylate Substituted alkyl such as benzyl methacrylate, 2-chloroethyl methacrylate, N, N-dimethylaminoethyl methacrylate, glycidyl methacrylate, benzyl acrylate, 2-chloroethyl acrylate, N, N-dimethylaminoethyl acrylate, glycidyl acrylate, etc. Also included are esters.

Further, in the polymer binder, monomers described in the following 1) to 14) can be used as copolymerization monomers.

1) Monomers having an aromatic hydroxyl group, such as o- (or p-, m-) hydroxystyrene, o- (or p-, m-) hydroxyphenyl acrylate, etc. 2) Monomers having an aliphatic hydroxyl group, such as 2 -Hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, N-methylol acrylamide, N-methylol methacrylamide, 4-hydroxybutyl methacrylate, 5-hydroxypentyl acrylate, 5-hydroxypentyl methacrylate, 6-hydroxyhexyl acrylate, 6-hydroxyhexyl Methacrylate, N- (2-hydroxyethyl) acrylamide, N- (2-hydroxyethyl) methacrylamide, hydroxyethyl vinyl ether, etc. 3) Monomer having an aminosulfonyl group, eg For example, m- (or p-) aminosulfonylphenyl methacrylate, m- (or p-) aminosulfonylphenyl acrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- (p-aminosulfonylphenyl) acrylamide, etc. 4 ) Monomers having sulfonamide groups such as N- (p-toluenesulfonyl) acrylamide, N- (p-toluenesulfonyl) methacrylamide 5) Acrylamide or methacrylamides such as acrylamide, methacrylamide, N-ethylacrylamide N-hexylacrylamide, N-cyclohexylacrylamide, N-phenylacrylamide, N- (4-nitrophenyl) acrylamide, N-ethyl-N-phenylacrylamide, N- (4-hydro Siphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide, etc. 6) Monomers containing alkyl fluoride groups such as trifluoroethyl acrylate, trifluoroethyl methacrylate, tetrafluoropropyl methacrylate, hexafluoropropyl methacrylate, octafluoro Pentyl acrylate, octafluoropentyl methacrylate, heptadecafluorodecyl methacrylate, N-butyl-N- (2-acryloxyethyl) heptadecafluorooctylsulfonamide and the like.

7) Vinyl ethers such as ethyl vinyl ether, 2-chloroethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether, phenyl vinyl ether, etc. 8) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl benzoate 9) Styrenes such as styrene, methyl styrene, chloromethyl styrene 10) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, phenyl vinyl ketone 11) Olefins such as ethylene and propylene I-butylene, butadiene, isoprene, etc. 12) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, etc. 13) Monomer having a cyano group, For example, acrylonitrile, methacrylonitrile, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, o- (or m-, p-) cyanostyrene, etc. 14) monomers having amino groups, for example N, N-diethylaminoethyl methacrylate, N, N-dimethylaminoethyl acrylate, N, N-dimethylaminoethyl methacrylate, polybutadiene urethane acrylate, N, N-dimethylaminopropyl acrylamide, N, N-dimethylacrylamide, acryloylmorpholine, N -I-propylacrylamide, N, N-diethylacrylamide, etc.

Further, other monomers that can be copolymerized with these monomers may be copolymerized.

Furthermore, the polymer binder is preferably a vinyl polymer having a carboxyl group and a polymerizable double bond in the side chain. For example, an unsaturated bond-containing vinyl copolymer obtained by addition-reacting a compound having a (meth) acryloyl group and an epoxy group in the molecule to a carboxyl group present in the molecule of the vinyl copolymer. Is also preferred as a polymer binder.

Specific examples of the compound containing both an unsaturated bond and an epoxy group in the molecule include glycidyl acrylate, glycidyl methacrylate, and an epoxy group-containing unsaturated compound described in JP-A No. 11-271969. Also, an unsaturated bond-containing vinyl copolymer obtained by adding a compound having a (meth) acryloyl group and an isocyanate group in the molecule to the hydroxyl group present in the molecule of the vinyl polymer is also high. Preferred as a molecular binder.

Compounds having both an unsaturated bond and an isocyanate group in the molecule include vinyl isocyanate, (meth) acrylic isocyanate, 2- (meth) acryloyloxyethyl isocyanate, m- or p-isopropenyl-α, α'-dimethylbenzyl. Isocyanates are preferred, and examples include (meth) acrylic isocyanate and 2- (meth) acryloyloxyethyl isocyanate.

The vinyl polymer having a carboxyl group and a polymerizable double bond in the side chain is preferably 50 to 100% by mass and more preferably 100% by mass in the total polymer binder.

The content of the polymer binder in the photosensitive layer is preferably in the range of 10 to 90% by weight, more preferably in the range of 15 to 70% by weight, and the use in the range of 20 to 50% by weight from the viewpoint of sensitivity. Particularly preferred.

(Various additives)
In addition to the above-mentioned various components, the photosensitive layer according to the present invention is polymerized in order to prevent unnecessary polymerization of a polymerizable ethylenic double bond monomer during production or storage of the photosensitive lithographic printing plate material. It is desirable to add an inhibitor.

Suitable polymerization inhibitors include 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), N-nitrosophenylhydroxylamine cerium salt, 2-t-butyl-6- (3-t-butyl-2-hydroxy-) And 5-methylbenzyl) -4-methylphenyl acrylate.

The addition amount of the polymerization inhibitor is preferably 0.01 to 5% by mass relative to the total solid content of the photosensitive layer. In addition, if necessary, higher fatty acid derivatives such as behenic acid and behenic acid amide are added to prevent polymerization inhibition by oxygen, or they are unevenly distributed on the surface of the photosensitive layer in the process of drying after coating. Also good. The addition amount of the higher fatty acid derivative is preferably 0.5 to 10% by mass of the total composition.

In addition, a colorant can also be used, and a conventionally known colorant including a commercially available one can be suitably used as the colorant. For example, those described in the revised new edition “Pigment Handbook” edited by Japan Pigment Technology Association (Seikodo Shinkosha), Color Index Handbook, and the like.

Examples of pigments include black pigments, yellow pigments, red pigments, brown pigments, purple pigments, blue pigments, green pigments, fluorescent pigments, and metal powder pigments. Specifically, inorganic pigments (titanium dioxide, carbon black, graphite, zinc oxide, Prussian blue, cadmium sulfide, iron oxide, and lead, zinc, barium and calcium chromates) and organic pigments (azo-based, thioindigo) , Anthraquinone, anthanthrone, and triphendioxazine pigments, vat dye pigments, phthalocyanine pigments and derivatives thereof, quinacridone pigments, and the like.

Among these, it is preferable to select and use a pigment having substantially no absorption in the absorption wavelength region of the spectral sensitizing dye corresponding to the exposure laser to be used. In this case, an integrating sphere at the laser wavelength to be used is used. It is preferable that the reflection absorption of the used pigment is 0.05 or less. The addition amount of the pigment is preferably from 0.1 to 10% by mass, more preferably from 0.2 to 5% by mass, based on the solid content of the composition.

From the viewpoints of pigment absorption in the above-mentioned photosensitive wavelength region and visible image properties after development, it is preferable to use a purple pigment or a blue pigment. Such as, for example, cobalt blue, cerulean blue, alkali blue lake, phonatone blue 6G, Victoria blue lake, metal-free phthalocyanine blue, phthalocyanine blue first sky blue, indanthrene blue, indico, dioxane violet, Examples include isoviolanthrone violet, indanthrone blue, and indanthrone BC. Among these, phthalocyanine blue and dioxane violet are more preferable.

Further, the photosensitive layer can contain a surfactant as a coating property improving agent as long as the performance of the present invention is not impaired. Of these, fluorine-based surfactants are preferred.

In order to improve the physical properties of the cured film, additives such as inorganic fillers and plasticizers such as dioctyl phthalate, dimethyl phthalate and tricresyl phosphate may be added. These addition amounts are preferably 10% by mass or less based on the total solid content.

Examples of the solvent used in preparing the photosensitive layer coating solution for the photosensitive layer according to the present invention include, for example, alcohol: polyhydric alcohol derivatives such as sec-butanol, isobutanol, n-hexanol, benzyl alcohol, Diethylene glycol, triethylene glycol, tetraethylene glycol, 1,5-pentanediol, and ethers: propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, ketones, aldehydes: diacetone alcohol, cyclohexanone Preferred examples include methylcyclohexanone and esters: ethyl lactate, butyl lactate, diethyl oxalate, methyl benzoate and the like.

Although the photosensitive layer coating solution has been described above, the photosensitive layer according to the present invention is constituted by coating on a support using this.

In the photosensitive layer according to the present invention, the coating amount on the support is preferably from 0.1 to 10 g / m ² , particularly preferably from 0.5 to 5 g / m ² .

(Oxygen barrier layer)
On the upper side of the photosensitive layer according to the present invention, an oxygen blocking layer having oxygen blocking and other protective functions as required can be provided.

This oxygen barrier layer is preferably highly soluble in an aqueous solution that removes the aforementioned unexposed image portion, and is characterized by containing polyvinyl alcohol. Polyvinyl alcohol has an effect of suppressing the permeation of oxygen. In addition, it is preferable to use together polyvinyl pyrrolidone which has the effect of ensuring the adhesiveness with the adjacent photosensitive layer.

In addition to the above two polymers, polysaccharides, polyethylene glycol, gelatin, glue, casein, hydroxyethyl cellulose, carboxymethyl cellulose, methyl cellulose, hydroxyethyl starch, gum arabic, sucrose octaacetate, ammonium alginate, sodium alginate as required Water-soluble polymers such as polyvinylamine, polyethylene oxide, polystyrene sulfonic acid, polyacrylic acid, and water-soluble polyamide can also be used in combination.

When an oxygen blocking layer is provided on the photosensitive lithographic printing plate of the present invention, the peeling force between the photosensitive layer and the oxygen blocking layer is preferably 35 mN / mm or more, more preferably 50 mN / mm or more, and even more preferably 75 mN / mm. That's it. Preferable oxygen barrier layer compositions include those described in JP-A-10-10742.

The peeling force in the present invention is that an adhesive tape having a predetermined width having a sufficiently large adhesive force is applied on the oxygen barrier layer and peeled off with the oxygen barrier layer at an angle of 90 degrees with respect to the plane of the photosensitive lithographic printing plate material. It can be determined by measuring the force of time.

The oxygen barrier layer can further contain a surfactant, a matting agent and the like as required. The oxygen barrier layer composition is dissolved in a suitable solvent, applied onto the photosensitive layer and dried to form an oxygen barrier layer. The main component of the coating solvent is particularly preferably water or alcohols such as methanol, ethanol and i-propanol.

When the oxygen barrier layer is provided, the thickness is preferably 0.1 to 5.0 μm, particularly preferably 0.5 to 3.0 μm.

(Support)
The support according to the present invention is a plate or film capable of carrying a photosensitive layer, and preferably has a hydrophilic surface on the side where the photosensitive layer is provided.

As the support according to the present invention, for example, a metal plate such as aluminum, stainless steel, chromium, nickel or the like, or a laminate obtained by laminating or vapor-depositing the above metal thin film on a plastic film such as a polyester film, a polyethylene film, or a polypropylene film, etc. It is done.

Also, a surface of a polyester film, vinyl chloride film, nylon film or the like that has been subjected to a hydrophilic treatment can be used, but an aluminum support is preferably used. In the case of an aluminum support, pure aluminum or an aluminum alloy is used.

Various aluminum alloys can be used as the support, and for example, an alloy of a metal such as silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth, nickel, titanium, sodium, iron, and aluminum is used. Moreover, the thing which roughened the surface for water support provision is used for an aluminum support body.

In the case of using an aluminum support, it is preferable to perform a degreasing treatment to remove the rolling oil on the surface prior to roughening (graining treatment). As the degreasing treatment, a degreasing treatment using a solvent such as trichlene or thinner, an emulsion degreasing treatment using an emulsion such as kesilon or triethanol, or the like is used. An alkaline aqueous solution such as caustic soda can also be used for the degreasing treatment. When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, dirt and oxide film that cannot be removed only by the degreasing treatment can be removed. When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, smut is generated on the surface of the support. In this case, the substrate is immersed in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid, or a mixed acid thereof and desmutted. It is preferable to perform the treatment. Examples of the roughening method include a mechanical method and a method of etching by electrolysis.

The mechanical surface roughening method used is not particularly limited, but a brush polishing method and a honing polishing method are preferable. The electrochemical surface roughening method is not particularly limited, but a method of electrochemical surface roughening in an acidic electrolyte is preferable.

After the surface roughening by the electrochemical surface roughening method, it is preferable to immerse in an acid or alkali aqueous solution in order to remove aluminum scraps on the surface. Examples of the acid include sulfuric acid, persulfuric acid, hydrofluoric acid, phosphoric acid, nitric acid, hydrochloric acid, and the like. Examples of the base include sodium hydroxide and potassium hydroxide. Among these, it is preferable to use an alkaline aqueous solution.

The amount of aluminum dissolved on the surface is preferably 0.5 to 5 g / m ² . Further, it is preferable to perform a neutralization treatment after immersion treatment with an aqueous alkali solution and then immersion in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid or a mixed acid thereof.

The mechanical surface roughening method and the electrochemical surface roughening method may each be used alone for roughing, or the mechanical surface roughening method followed by the electrochemical surface roughening method. You may roughen.

Anodizing treatment can be performed after the roughening treatment. There is no restriction | limiting in particular in the method of the anodizing process which can be used in this invention, A well-known method can be used. By performing the anodizing treatment, an oxide film is formed on the support.

The anodized support may be subjected to a sealing treatment as necessary. These sealing treatments can be performed using known methods such as hot water treatment, boiling water treatment, water vapor treatment, sodium silicate treatment, dichromate aqueous solution treatment, nitrite treatment, and ammonium acetate treatment.

Further, after these treatments, water-soluble resins such as polyvinylphosphonic acid, polymers and copolymers having sulfonic acid groups in the side chain, polyacrylic acid, water-soluble metal salts (for example, zinc borate) Also suitable are those coated with a yellow dye, amine salt or the like. Further, a sol-gel treated substrate in which a functional group capable of causing an addition reaction by a radical is covalently bonded as disclosed in JP-A-5-304358 is also preferably used.

(Application)
The photosensitive layer coating solution can be applied onto a support by a conventionally known method and dried to prepare a photosensitive lithographic printing plate material.

Examples of coating methods for the coating liquid include air doctor coater method, blade coater method, wire bar method, knife coater method, dip coater method, reverse roll coater method, gravure coater method, cast coating method, curtain coater method and extrusion coater method. Can be mentioned.

The drying temperature of the photosensitive layer is preferably 60 to 160 ° C., more preferably 80 to 140 ° C., particularly preferably 90 to 120 ° C.

(Image exposure)
As a light source for recording an image on the photosensitive lithographic printing plate material according to the present invention, it is preferable to use a laser beam having an emission wavelength of 350 to 450 nm.

As a light source for exposure, for example, a He—Cd laser (441 nm), a combination of Cr: LiSAF and SHG crystal (430 nm) as a solid-state laser, KNbO ₃ as a semiconductor laser system, a ring resonator (430 nm), AlGaInN (350 to 350 nm) 450 nm), AlGaInN semiconductor laser (commercially available InGaN-based semiconductor laser 400 to 410 nm), and the like.

In the case of laser exposure, light can be narrowed down in the form of a beam and scanning exposure according to image data is possible, so that it is suitable for direct writing without using a mask material. When a laser is used as a light source, it is easy to reduce the exposure area to a very small size, and high-resolution image formation is possible.

Laser scanning methods include cylindrical outer surface scanning, cylindrical inner surface scanning, and planar scanning. In the cylindrical outer surface scanning, laser exposure is performed while rotating a drum around which the recording material is wound, and the rotation of the drum is set as main scanning, and the movement of laser light is set as sub scanning. In cylindrical inner surface scanning, a recording material is fixed to the inner surface of the drum, a laser beam is irradiated from the inside, and a main scanning is performed in the circumferential direction by rotating part or all of the optical system, and part or all of the optical system is performed. Is linearly moved parallel to the axis of the drum to perform sub-scanning in the axial direction. In planar scanning, main scanning of laser light is performed by combining a polygon mirror or galvanometer mirror and an fθ lens, and sub scanning is performed by moving a recording medium. Cylindrical outer surface scanning and cylindrical inner surface scanning are easier to increase the accuracy of the optical system and are suitable for high-density recording.

In the present invention, image exposure is preferably performed with a plate surface energy (energy on the plate material) of 10 mJ / cm ² or more, and the upper limit is 500 mJ / cm ² . More preferably, it is 10 to 300 mJ / cm ² . For this energy measurement, for example, a laser power meter PDGDO-3W manufactured by OphirOptics can be used.

(Automatic processor)
In order to remove the image unexposed portion of the photosensitive lithographic printing plate material according to the present invention with an aqueous solution containing a water-soluble resin and a surfactant and having a pH of 3.0 to 9.0 at 25 ° C. It is advantageous to use an automatic developing machine used for developing a general photosensitive lithographic printing plate material.

The automatic processor is preferably equipped with a heat treatment apparatus for performing a heat treatment after inserting the exposed photosensitive lithographic printing plate material and before removing the unexposed portion. The heat treatment apparatus is one that performs heat treatment using radiant heat such as a ceramic heater, or one that performs heat treatment using hot air heated by a ceramic heater or the like, and the temperature of the plate surface is an arbitrary temperature in the range of 80 to 160 ° C. What can be adjusted is preferable.

Further, it can have a water washing part for removing part of the oxygen blocking layer and the photosensitive layer after the heat treatment. Examples of the washing unit include those equipped with a shower nozzle that supplies washing water to the plate surface, and those that immerse the plate in a washing tank filled with washing water. Those provided with a mechanism for rubbing the plate surface with a roller-like brush are also preferred.

In the step of removing the unexposed portion of the image with an aqueous solution containing a water-soluble resin and a surfactant and having a pH of 3.0 to 9.0 at a temperature of 25 ° C., a conventional general photosensitive lithographic printing plate material is used. A developing bath of an automatic developing machine used for development processing can be used.

The developing bath preferably has a mechanism capable of adjusting the aqueous solution to a constant temperature. It is preferable that the temperature adjustment can be arbitrarily set within a range of 20 to 35 ° C.

The developing bath preferably has the following mechanism.

1) Mechanism for automatically replenishing the required amount of the aqueous solution 2) Mechanism for discharging the aqueous solution exceeding a certain amount 3) Mechanism for detecting plate passing 4) Mechanism for estimating the processing area of the plate based on detection of plate passing 5) Mechanism for controlling replenishment amount and replenishment timing of replenisher to be replenished based on detection of plate passing, estimation of processing area 6) Mechanism for controlling temperature of the aqueous solution 7) pH and conductivity of the aqueous solution 8) A mechanism for controlling the replenisher to be replenished based on the pH and conductivity of the aqueous solution, the replenishment amount of water, and the replenishment timing.

Hereinafter, although an example is given and the present invention is explained in detail, the mode of the present invention is not limited to this. In the examples, “parts” represents “parts by mass” unless otherwise specified.

Example 1
<Production of support>
Using a JIS A 1050 aluminum plate having a thickness of 0.30 mm and a width of 1030 mm, the treatment was continuously performed as follows.

(A) The aluminum plate was etched by spraying at a caustic soda concentration of 2.6 mass%, an aluminum ion concentration of 6.5 mass%, and a temperature of 70 ° C. to dissolve the aluminum plate by 0.3 g / m ² . Then, water washing by spraying was performed.

(B) A desmut treatment was performed by spraying with a 1% by mass aqueous solution of nitric acid at a temperature of 30 ° C. (including 0.5% by mass of aluminum ions), and then washed with water by spraying.

(C) An electrochemical surface roughening treatment was continuously performed using an alternating voltage of 60 Hz. The electrolytic solution at this time contains 1.1% by mass of hydrochloric acid, 0.5% by mass of aluminum ions, and 0.5% by mass of acetic acid. The temperature was 21 ° C. The AC power source was subjected to electrochemical surface roughening treatment using a sine wave alternating current having a time TP of 2 msec until the current value reached a peak from zero, using a carbon electrode as a counter electrode. The current density was 50 A / dm ^{2 as} an effective value, and the energization amount was 900 C / dm ² . Then, water washing by spraying was performed.

(D) A desmut treatment was performed for 10 seconds with a 20% by mass aqueous solution of phosphoric acid having a temperature of 60 ° C. (containing 0.5% by mass of aluminum ions), and then washed with water by spraying.

(E) An anodizing apparatus using an existing two-stage feed electrolytic treatment method (first and second electrolysis unit length 6 m, first feed unit length 3 m, second feed unit length 3 m, first and second feed electrode lengths 2.4 m each ) Was used to perform anodization at a sulfuric acid concentration of 170 g / L (containing 0.5 mass% of aluminum ions) at a temperature of 38 ° C. Then, water washing by spraying was performed.

At this time, in the anodizing apparatus, the current from the power source flows to the first power supply electrode provided in the first power supply portion, flows to the plate-like aluminum via the electrolytic solution, and the surface of the plate-like aluminum in the first electrolysis portion. Then, an oxide film is formed, passes through the electrolytic electrode provided in the first power feeding portion, and returns to the power source.

On the other hand, the current from the power source flows to the second power feeding electrode provided in the second power feeding part, and similarly flows to the plate-like aluminum via the electrolytic solution, and an oxide film is generated on the surface of the plate-like aluminum by the second electrolytic part. However, the amount of electricity fed from the power source to the first feeding unit and the amount of electricity fed from the power source to the second feeding unit are the same, and the feeding current density on the oxide film surface in the second feeding unit is about 25 A / dm ² . In the 2nd electric power feeding part, it came to feed from the oxide film surface of 1.35 g / m < ² >.
The final oxide film amount was 2.7 g / m ² . Furthermore, after spray water washing, it was immersed in a 0.4 mass% polyvinylphosphonic acid solution for 30 seconds and hydrophilized. The temperature was 85 ° C. Then, it spray-washed and dried with the infrared heater. At this time, the center line average roughness (Ra) of the surface was 0.65 μm.

[Preparation of photosensitive lithographic printing plate]
A photopolymerizable photosensitive layer coating solution 1 having the following composition was coated on the above support with a wire bar so that the dried liquid was 1.5 g / m ² and dried at 95 ° C. for 1.5 minutes. Got.

Further, on the photopolymerized photosensitive layer coating sample, an oxygen blocking layer coating solution having the following composition was coated with a wire bar so as to have a dry weight of 2.0 g / m ² and dried at 65 ° C. for 3 minutes. A photosensitive lithographic printing plate material having a barrier layer was prepared.

(Photopolymerizable photosensitive layer coating solution 1)
Polymerizable monomer 1 5.0 parts Polymerizable monomer 2 25.0 parts Polymerizable monomer 3 25.0 parts N-carboxymethylacridone 4.0 parts 2,2'-bis (2-chlorophenyl) -4,4 ' , 5,5'-Tetraphenylbisimidazole 3.0 parts 2-mercaptooxazole 0.3 part N-vinylpyrrolidone / vinyl acetate copolymer VA64 (manufactured by BASF) 20.0 parts Poly (N-vinylpyrrolidone) Rubytec K30 (Manufactured by BASF) 20.0 parts Acetylene-based surfactant (Surfinol 465; manufactured by Air Products) 0.5 part Phthalocyanine pigment dispersion MHI # 454 (manufactured by Gokoku Dye) 3.0 parts Water 450 parts D Nord 450 parts

(Oxygen barrier coating liquid)
Polyvinyl alcohol (GL-05: manufactured by Nippon Synthetic Chemical Co., Ltd.) 90 parts Poly (N-vinylpyrrolidone) Rubitec K30 (manufactured by BASF) 5 parts Polyethyleneimine (Lupazole WF: manufactured by BASF) 5 parts Surfactant (Surfinol 465: Nissin) Chemical Co., Ltd.) 0.5 parts Water 900 parts The photosensitive lithographic printing plate material produced by the above method is subjected to resolution using a plate setter News (manufactured by ECRM) equipped with a light source of 405 nm in an environment of yellow safety light. The exposure was performed at 1200 dpi (dpi represents the number of dots per 2.54 cm) and the number of lines of 100 lpi (lpi represents the number of lines per 2.54 cm) while changing the exposure amount.

After the exposure, the photosensitive lithographic printing plate material was subsequently heat-treated at 105 ° C. for 30 seconds in a red safety light environment, and then the plate surface was washed with a tap water shower for 15 seconds to remove the oxygen barrier layer. At this time, a part of the unexposed portion of the photosensitive layer was also removed. Thereafter, the surface was rubbed with a sponge while immersed in an aqueous solution (1 to 15) shown in Table 1 for 20 seconds to completely remove the unexposed portion and then dried to obtain a photosensitive lithographic printing plate.

Further, instead of the photopolymerizable photosensitive layer coating solution 1, a photolithographic printing plate was prepared in the same manner as described above using the following photopolymerizable photosensitive layer coating solution 2.

Table 2 shows photosensitive lithographic printing plates (1 to 18) obtained by treating the photosensitive lithographic printing plate materials from the photopolymerizable photosensitive layer coating solutions 1 and 2 with the aqueous solutions (1 to 15) shown in Table 1. .

(Photopolymerizable photosensitive layer coating solution 2)
Polymerizable monomer 1 5.0 parts Polymerizable monomer 2 25.0 parts Polymerizable monomer 3 25.0 parts N-carboxymethylacridone 4.0 parts 2,2'-bis (2-chlorophenyl) -4,4 ' , 5,5'-tetraphenylbisimidazole 3.0 parts 2-mercaptooxazole 0.3 part 20.0 parts of the following binder polymer (1) Acetylene surfactant (Surfinol 465; manufactured by Air Products) 0.5 part Phthalocyanine pigment dispersion MHI # 454 (manufactured by Gokoku Dye) 3.0 parts Methyl ethyl ketone 100 parts Ethanol 820 parts

The produced photosensitive lithographic printing plate is coated with a printing machine (DAIYA1F-1 manufactured by Mitsubishi Heavy Industries, Ltd.), printing ink (Toyo King High Echo M Red manufactured by Toyo Ink Co., Ltd.) and fountain solution (Tokyo Ink). Printing was performed using H liquid SG-51 (manufactured by Co., Ltd., 1.5% by mass).

[Evaluation]
(Print life)
An evaluation chart of 100 lines exposed at 50 μj / cm ² was printed under the printing conditions below, and the printing durability was defined as the number of printed sheets from the start of printing until the reproduction halftone dot changed by 3%.

<Printing conditions>
Printing machine: DAIYA1F-1: Mitsubishi Heavy Industries Paper: Coated paper (Recycled pulp content 20%, Hokuetsu Paper)
Blanket: SR100 (made by SRI Hybrid)
Printing ink: Soybean oil ink Naturalis 100 (Y, M, C, K): Dainippon Ink &Chemicals' fountain solution: H liquid SG-51 concentration 1.5% by mass: Tokyo ink printing speed: 4000 sheets / Time.

(Dirty non-image area)
The stain on the non-image area on the printed material was evaluated.

○: There is almost no ink stain. Δ: The ink stain can be confirmed with a loupe. ×: The ink stain is visually confirmed.

From Table 2, the sample having a pH outside the range of 3 to 9, and not a chelate compound represented by the general formula (1) according to the present invention but a sample using a conventionally known chelating agent, printing durability, It is apparent that the non-image area is poorly stained.

Claims (4)

After image exposure of a photosensitive lithographic printing plate material having a photosensitive layer containing a spectral sensitizer, a polymerization initiator, a polymerizable monomer and a polymer binder on a support, a water-soluble resin, a surfactant and the following general formula A photosensitive lithographic printing plate obtained by treatment with an aqueous solution having a pH of 3.0 to 9.0 containing the compound represented by (1).

(In the formula, A ₁ represents an alkyl group having 1 to 5 carbon atoms, an aryl group, or — (CH ₂ ) _n COOM. M, M ₁ , M ₂ , and M ₃ are each independently a hydrogen atom, an alkali metal, or ammonium. Represents a group, n represents 0, 1 or 2) 2. The photosensitive lithographic printing plate according to claim 1, wherein the content of the compound represented by the general formula (1) is 0.01 to 1.0% by mass. The photosensitive lithographic printing plate according to claim 1 or 2, wherein a hexaarylbisimidazole compound is used as the polymerization initiator. A printing method comprising printing the photosensitive lithographic printing plate according to any one of claims 1 to 3 with dampening water and printing ink applied thereto.