JP2005331802A - Making method of photosensitive lithographic printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a making method of a photosensitive lithographic printing plate, excellent in avoiding stop staining at printing and staining by the sludge of the developing solution, and also in maintenance for developing. <P>SOLUTION: This is a manufacturing method of a photosensitive lithographic printing plate by developing a photosensitive lithographic printing plate having a photopolymerizing photosensitive layer containing (A) a photopolymerizing initiator, (B) a macromolecule binder material, and (C) a polymerizing ethylene unsaturated bond containing compound by using a developing solution consisting of an alkaline water solution, after exposing to light. This alkaline water solution contains the compound expressed in the general formula (1), and this photopolymerizing photosensitive layer contains a metal arene compound as the above (A) photopolymerizing initiator. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for making a photopolymerization type photosensitive lithographic printing plate using aluminum as a support.

  In recent years, CTP recording digital image data directly on a photosensitive printing plate with a laser light source has been developed and is being put to practical use in the technology for producing printing plates for offset printing.

  Among these, in the field of printing that requires a relatively high printing durability, it is known to use a negative photosensitive lithographic printing plate material having a polymerization type photosensitive layer containing a polymerizable compound. (For example, refer to Patent Document 1).

  As the polymerization type photosensitive layer, one having a photosensitive layer containing an iron arene compound as a polymerization initiator for the purpose of high sensitivity is known (for example, see Patent Document 2), and has high sensitivity and high printing durability. For the purpose, a photosensitive layer containing a photoreductive dye containing a metallocene compound, a trihalomethyl compound, and a xanthene dye is known (for example, see Patent Document 3).

  As a developer for a lithographic printing plate material having this photopolymerization type photosensitive layer, it is generally known to use an alkaline solution.

  As alkaline solutions, for example, solutions containing alkali silicates described in JP-A-8-248643 and JP-A-11-65129 are known.

  In the case of a solution containing these alkali silicate salts, there is a problem that the image portion is easily damaged when the pH is high, and the developer is easily gelled and insolubilized when the pH is low.

  As a developer containing no alkali silicate salt, for example, JP-A 61-109052 discloses a developer comprising an alkali reagent, a complexing agent, an anionic surfactant, an emulsifier, n-alkanoic acid, and the like. However, there was much damage to the image area, which was insufficient to obtain high printing durability.

  Further, as a developer having a relatively low pH and containing no silicate, for example, a potassium hydroxide aqueous solution containing an anionic surfactant is disclosed in JP-A No. 2000-81711, and a pH of 8.5-11 is disclosed in JP-A No. 11-65126. .5 alkaline metal carbonate aqueous solutions are disclosed.

  As a problem of development at such a relatively low pH, there is a problem that the developability may be insufficient because the solubility of the photopolymerizable photosensitive layer is basically poor.

  Furthermore, for the purpose of improving these problems, a developer containing an inorganic alkali agent and a nonionic surfactant having a polyoxyalkylene ether group is used for developing a lithographic printing plate material having a photopolymerizable photosensitive layer. It is known (see, for example, Patent Document 4 and Patent Document 5).

  However, when these developers are used for the photosensitive lithographic printing plate described above, when the printing is temporarily stopped and printing is resumed, fine spots (hereinafter referred to as stop dirt) are present on the non-image area. In particular, this is remarkable in printing using a printing ink that does not use a non-petroleum-based volatile organic compound (VOC) that has recently been used for environmental protection.

In addition, the sludge generated in the developing solution, particularly when processing a relatively large amount of printing plate material using an automatic processor for development or when using the developing solution for a relatively long period of time, is used. Caused problems such as smearing during printing.
Japanese Patent Laid-Open No. 10-104835 JP-A-1-152109 JP-A-2-127404 JP 2002-196507 A JP 2002-91015 A

  An object of the present invention is to provide a method for making a photosensitive lithographic printing plate which is excellent in prevention of stains due to stop stains during development and sludge of a developer, and excellent in maintenance of development.

  The object of the present invention is achieved by the following constitution.

(Claim 1)
Photosensitive lithographic plate having a photopolymerizable photosensitive layer containing (A) a photopolymerization initiator, (B) a polymer binder, and (C) a polymerizable, ethylenically unsaturated bond-containing compound on an aluminum support. In the plate making method of a photosensitive lithographic printing plate in which a printing plate is subjected to image exposure and then developed with a developer comprising an alkaline aqueous solution, the alkaline aqueous solution contains a compound represented by the following general formula (1), and the photopolymerizable feeling A method for making a photosensitive lithographic printing plate, wherein the light-sensitive layer contains a metal arene compound as the photopolymerization initiator (A).

[Wherein R ₁ represents the following general formula (2) or —CH ₂ CH ₂ OX, R ₂ represents —CH ₂ COOX or —CH ₂ CH ₂ OX, and X represents a hydrogen atom or an alkali metal. ]

[Wherein, A represents an alkylene group having 1 to 5 carbon atoms which may have a substituent, and X represents a hydrogen atom or an alkali metal. ]
(Claim 2)
2. The plate making method of a photosensitive lithographic printing plate according to claim 1, wherein the developer contains 0.01% by mass to 5% by mass of the compound represented by the general formula (1).

(Claim 3)
The plate making method of a photosensitive lithographic printing plate according to claim 1 or 2, wherein the alkaline aqueous solution contains a surfactant having a polyoxyethylene group.

  According to the configuration of the present invention, it is possible to provide a plate making method of a photosensitive lithographic printing plate that has excellent anti-stain properties due to stop stains during printing and sludge of the developer, and excellent maintenance of development.

  The present invention provides a photopolymerizable photosensitive layer containing (A) a photopolymerization initiator, (B) a polymer binder, and (C) a polymerizable, ethylenically unsaturated bond-containing compound on an aluminum support. In the process for making a photosensitive lithographic printing plate, the photosensitive lithographic printing plate having image exposure, and then developing with an aqueous alkaline solution, the aqueous alkaline solution contains a compound represented by the following general formula (1), and the photopolymerizable feeling The light-sensitive layer contains a metal arene compound as the photopolymerization initiator (A).

  In the present invention, the photosensitive lithographic printing plate is developed after image exposure, and in the unexposed area, the photopolymerizable photosensitive layer is removed, and the support is exposed to form a water-receptive non-image area.

(Developer-alkaline aqueous solution)
In the present invention, the photosensitive lithographic printing plate subjected to image exposure is developed with a developer composed of an alkaline aqueous solution containing a compound represented by the general formula (1).

  The aqueous solution means that 95% by mass or more of the solvent in the developer is water.

  As the developer according to the present invention, an alkaline aqueous solution containing an alkali agent and having a pH of 8.5 to 12.5 is preferably used.

In the general formula (1), R ₁ represents the general formula (2) or —CH ₂ CH ₂ OX, R ₂ represents —CH ₂ COOX or —CH ₂ CH ₂ OX, and X represents a hydrogen atom or an alkali. Represents a metal.

  In the general formula (2), A represents an alkylene group having 1 to 5 carbon atoms which may have a substituent.

  The number of carbon atoms other than the substituent of the alkylene group represented by A is preferably 2, and examples of the substituent include a hydroxyl group and an alkyl group having 1 to 3 carbon atoms (for example, a methyl group and an ethyl group).

  The compound represented by the general formula (1) is presumed to function in order to effectively dissolve the iron ions and iron hydroxide generated by the decomposition of the iron arene compound present in the photosensitive layer composition. The

  The content of the compound represented by the general formula (1) with respect to the alkaline aqueous solution is preferably 0.01 to 5% by mass, particularly preferably 0.1 to 1.5% by mass.

(Alkaline agent)
Examples of the alkaline agent include dibasic sodium phosphate, potassium, and ammonium; sodium bicarbonate, potassium, and ammonium; sodium carbonate, potassium, and ammonium; sodium bicarbonate, potassium, and ammonium; sodium borate, Inorganic alkaline agents such as sodium hydroxide, potassium, ammonium and lithium, sodium silicate, potassium silicate, and the like.

  Also, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, mono-i-propylamine, di-i-propylamine, tri-i-propylamine, butylamine, monoethanolamine, diethanolamine, triethanolamine, Organic alkali agents such as mono-i-propanolamine, di-i-propanolamine, ethyleneimine, ethylenediamine, and pyridine can also be used.

  In addition to the above salts, salts such as sulfosalicylic acid, salicylic acid, sugar alcohols of non-reducing sugars, saccharose, D-sorbit and the like can also be used.

  Of these, carbonates and silicates are preferably used.

  The content of the alkaline agent in the developer is preferably from 0.1% by mass to 10% by mass, and the pH is preferably adjusted to 8.5 to 12.5 within this range.

  Specific examples of the compound represented by the general formula (1) include, but are not limited to, the following 1-1 to 1-7 and sodium and potassium salts thereof.

(Surfactant)
To the developer according to the present invention, other surfactants and organic solvents can be added as necessary for the purpose of promoting developability, dispersing development residue, and improving ink affinity of the printing plate image portion.

  Surfactants include anionic, cationic, nonionic and amphoteric surfactants. Preferred examples of the surfactant include polyoxyethylene alkyl ethers, polyoxyethylene aryl ether, ester polyoxyethylene alkyl phenyl ethers, polyoxyethylene naphthyl ether, polyoxyethylene polystyryl phenyl ethers, 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 partial ester, polyethylene glycol fatty acid ester , Polyglycerin fatty acid partial esters, polyoxyethylenated castor oil, polyoxyethylene glycerin fatty acid Branched esters, polyoxyethylene-polyoxypropylene block copolymers, polyoxyethylene-polyoxypropylene block copolymer adducts of ethylenediamine, fatty acid diethanolamides, N, N-bis-2-hydroxyalkylamines, Nonionic surfactants such as polyoxyethylene alkylamine, triethanolamine fatty acid ester, trialkylamine oxide, fatty acid salts, abietic acid salts, hydroxyalkane sulfonic acid salts, alkane sulfonic acid salts, dialkyl sulfosuccinic acid ester salts, Linear alkylbenzene sulfonates, branched alkylbenzene sulfonates, alkylnaphthalene sulfonates, polyoxyethylene aryl ether carboxylic acid, polyoxyethylene naphthyl ether Acid ester salt, alkyl diphenyl ether sulfonate, alkylphenoxy polyoxyethylene propyl sulfonate, polyoxyethylene alkyl sulfophenyl ether salt, polyoxyethylene aryl ether sulfate ester salt, N-methyl-N-oleyl taurine sodium salt, N -Alkylsulfosuccinic acid monoamide disodium salt, petroleum sulfonates, sulfated beef tallow oil, fatty acid alkyl ester sulfate ester salt, alkyl sulfate ester salt, polyoxyethylene alkyl ether sulfate ester salt, fatty acid monoglyceride sulfate ester, polyoxy Ethylene alkyl phenyl ether sulfates, polyoxyethylene styryl phenyl ether sulfates, alkyl phosphate esters, polyoxy Siethylene alkyl ether phosphates, polyoxyethylene alkyl phenyl ether phosphates, partially saponified styrene / maleic anhydride copolymers, partially saponified olefin / maleic anhydride copolymers, naphthalene sulfone Anionic surfactants such as acid salt formalin condensates, alkylamine salts, quaternary ammonium salts such as tetrabutylammonium bromide, cationic surfactants such as polyoxyethylene alkylamine salts, polyethylene polyamine derivatives, carboxybetaines And amphoteric surfactants such as aminocarboxylic acids, sulfobetaines, aminosulfuric esters, and imidazolines.

  Among these, the case of containing a surfactant having a polyoxyethylene group is a particularly preferred embodiment because the effect of the development treatment with the developer containing the compound of the general formula (1) is great.

(Development stabilizer)
Various developing stabilizers may be included in the developer according to the present invention. Preferred examples thereof include polyethylene glycol adducts of sugar alcohols described in JP-A-6-282079, tetraalkylammonium salts such as tetrabutylammonium hydroxide, phosphonium salts such as tetrabutylphosphonium bromide, and iodonium such as diphenyliodonium chloride. A salt is a preferred example.

  Further, there are water-soluble cationic polymers described in JP-A-55-95946 and water-soluble amphoteric polymer electrolytes described in JP-A-56-142528. Further, an organoboron compound to which an alkylene glycol is added as disclosed in JP-A-59-84241, an alkylenediamine compound substituted with polyoxyethylene / polyoxypropylene as described in JP-A-60-129750, and JP-A-61-215554. Polyethylene glycol having a weight average molecular weight of 300 or more described in Japanese Patent Publication No. JP-A-2-39157, a water-soluble ethylene oxide addition compound obtained by adding 4 mol or more of ethylene oxide to an acid or alcohol, and a water-soluble polyalkylene compound. Can be mentioned.

(Organic solvent)
If necessary, an organic solvent may be added to the developer. As such an organic solvent, those having a solubility in water of about 10% by mass or less are suitable, and are preferably selected from those having 5% by mass or less. For example, 1-phenylethanol, 2-phenylethanol, 3-phenyl-1-propanol, 4-phenyl-1-butanol, 4-phenyl-2-butanol, 2-phenyl-1-butanol, 2-phenoxyethanol, 2- Benzyloxyethanol, o-methoxybenzyl alcohol, m-methoxybenzyl alcohol, p-methoxybenzyl alcohol, benzyl alcohol, cyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol and 4-methylcyclohexanol, N-phenylethanol Examples thereof include amines and N-phenyldiethanolamine.

  The content of the organic solvent is preferably 1% by mass or less, particularly preferably not contained, relative to the total mass of the developer used. “Substantially not contained” means 1% by mass or less.

(Reducing agent)
A reducing agent is added to the developer according to the present invention as necessary. This is to prevent stains on the printing plate. Preferable organic reducing agents include phenol compounds such as thiosalicylic acid, hydroquinone, metol, methoxyquinone, resorcin, and 2-methylresorcin, and amine compounds such as phenylenediamine and phenylhydrazine. More preferable inorganic reducing agents include sodium, potassium and ammonium salts of inorganic acids such as sulfurous acid, bisulfite, phosphorous acid, hydrogen phosphite, dihydrogen phosphite, thiosulfuric acid and dithionite. A salt etc. can be mentioned. Among these reducing agents, sulfites are particularly excellent in the antifouling effect. These reducing agents are preferably contained in the range of 0.05 to 5% by mass with respect to the developing solution at the time of use.

(Organic carboxylic acid)
If necessary, an organic carboxylic acid can be further added to the developer according to the present invention. Preferred organic carboxylic acids are aliphatic carboxylic acids and aromatic carboxylic acids having 6 to 20 carbon atoms. Specific examples of the aliphatic carboxylic acid include caproic acid, enanthylic acid, caprylic acid, lauric acid, myristic acid, palmitic acid and stearic acid, and particularly preferred are alkanoic acids having 8 to 12 carbon atoms. . Further, it may be an unsaturated fatty acid having a double bond in the carbon chain or a branched carbon chain.

  The aromatic carboxylic acid is a compound in which a carboxyl group is substituted on a benzene ring, naphthalene ring, anthracene ring or the like, and specifically includes o-chlorobenzoic acid, p-chlorobenzoic acid, o-hydroxybenzoic acid, p- Hydroxybenzoic acid, o-aminobenzoic acid, p-aminobenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 3, There are 5-dihydroxybenzoic acid, gallic acid, 1-hydroxy-2-naphthoic acid, 3-hydroxy-2-naphthoic acid, 2-hydroxy-1-naphthoic acid, 1-naphthoic acid, 2-naphthoic acid and the like. Naphthoic acid is particularly effective.

  The aliphatic and aromatic carboxylic acids are preferably used as sodium salts, potassium salts or ammonium salts in order to enhance water solubility. The content of the organic carboxylic acid in the developer used in the present invention is not particularly limited, but a preferable addition amount is 0.1 to 10% by mass with respect to the developer at the time of use. It is 5-4 mass%.

(Other additives)
In addition to the above, the following additives can be added to the developer according to the present invention in order to improve the developing performance. For example, neutral salts such as NaCl, KCl and KBr described in JP-A-58-75152, complexes such as [Co (NH ₃ )] ₆ Cl ₃ described in JP-A-59-121336, JP-A-56 Ampholytic polymer electrolytes such as a copolymer of vinylbenzyltrimethylammonium chloride and sodium acrylate described in JP-A-142258, organometallic surfactants containing Si, Ti, etc. described in JP-A-59-75255, JP And organic boron compounds described in JP-A-59-84241. The developer and replenisher used in the present invention may further contain a preservative, a colorant, a thickener, an antifoaming agent, a hard water softener, and the like, if necessary.

  Examples of the antifoaming agent include mineral oil, vegetable oil, alcohol, surfactant, silicone and the like described in JP-A-2-244143. Examples of the water softener include polyphosphoric acid and its sodium salt, potassium salt and ammonium salt, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, ethylenediaminedisuccinic acid, methyliminodiacetic acid, β-alaninediacetic acid, triethylenetetraminehexaacetic acid, hydroxyethylethylenediaminetrimethyl. Aminopolycarboxylic acids such as acetic acid, nitrilotriacetic acid, 1,2-diaminocyclohexanetetraacetic acid and 1,3-diamino-2-propanoltetraacetic acid and their sodium, potassium and ammonium salts, aminotri (methylenephosphonic acid), Ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphonic acid), triethylenetetraminehexa (methylenephosphonic acid) Hydroxyethyl ethylene diamine tri (methylene phosphonic acid) and 1-hydroxyethane-1,1-diphosphonic acid and their sodium salts, potassium salts and ammonium salts. The optimum value of such a hard water softening agent varies depending on its chelating power, the hardness of the hard water used and the amount of hard water. % By mass, more preferably in the range of 0.01 to 0.5% by mass. If the addition amount is less than this range, the intended purpose is not sufficiently achieved. If the addition amount is more than this range, adverse effects on the image area such as color loss will occur. The remaining component of the developer and replenisher is water. The conductivity of the obtained developer is more preferably in the range of 5 to 50 mS.

  It is advantageous in terms of transportation that the developer according to the present invention is a concentrated solution in which the water content is less than that in use, and is diluted with water at the time of use. The degree of concentration in this case is appropriate so that each component does not separate or precipitate, but it is preferable to add a solubilizing agent if necessary. As such a solubilizer, a so-called hydrotrope such as toluenesulfonic acid, xylenesulfonic acid and alkali metal salts thereof described in JP-A-6-32081 is preferably used.

  The content of water in the concentrate can be further reduced to form a solid or paste. In this case, the developer may be once evaporated and then evaporated to dryness, but it is preferable that the concentrated state is obtained by mixing the materials without adding water when adding a plurality of materials or by adding a small amount of water. Is preferred. The developer concentrates are disclosed in JP-A-51-61837, JP-A-2-109042, JP-A-2-109043, JP-A-3-39735, JP-A-5-142786, JP-A-6-266062, and JP-A-7- Granules and tablets can be obtained by a conventionally well-known method described in US Pat. As the material contained in the solid or paste developer concentrate, the components used in the developer of ordinary photopolymerizable photosensitive lithographic printing plates can be used, but even if diluted with water, It is preferable not to include anything that does not return. For example, since silicate is converted into stone when it becomes low in moisture, it becomes difficult to dissolve in water. Therefore, it is preferable to contain carbonate, phosphate, organic acid salt or the like instead of silicate.

  These developer concentrates or solid or paste concentrates may be divided into a plurality of parts having different material types, material blending ratios, and the like. These concentrated developer concentrates are preferably used for development after dilution to a predetermined concentration with water before development. In addition, when this developer concentrate or concentrate is used as a developer replenisher, it is most preferable to dilute with water to a predetermined concentration and then add it to the developer in use. It is also possible to put it in a developing solution as it is without diluting to a predetermined concentration. When adding the developer concentrate to a developing solution in use at a concentration higher than a predetermined concentration or without diluting to a predetermined concentration, water is added directly to the developing solution in use at the same timing or at another timing. May be added.

(Aluminum support)
An aluminum plate is used for the aluminum support according to the present invention. In this case, a pure aluminum plate, an aluminum alloy plate, or the like may be used.

  Various aluminum alloys can be used as the support, and for example, alloys of metals such as silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth, nickel, titanium, sodium, iron, and aluminum are used. . Further, the aluminum support having a roughened surface is used for water retention.

  Prior to roughening (graining treatment), it is preferable to perform a degreasing treatment in order to remove the rolling oil on the surface. 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. In addition, an alkaline aqueous solution such as caustic soda can 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 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 is roughened by the electrochemical surface roughening method, it is preferably immersed 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 dissolution amount of aluminum in the support surface, 0.5 to 5 g / m ² is preferred. In addition, it is preferable that after the immersion treatment with an alkaline aqueous solution, neutralization treatment is performed by immersion in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid or a mixed acid thereof.

  The mechanical surface roughening treatment method and the electrochemical surface roughening method may be used independently for roughening, or the mechanical surface roughening treatment method followed by the electrochemical surface roughening method may be used for roughening. You may face it.

  Following the roughening treatment, an anodic oxidation treatment can be performed. 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 sealed 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.

  Furthermore, in the present invention, after performing these treatments, a hydrophilic treatment is performed with a treatment liquid containing a compound containing P as described above.

  As described above, it is preferable to hydrophilize the support surface with polyvinylphosphonic acid as described above.

  The arithmetic average roughness (Ra) of the surface on the photosensitive layer side of the obtained aluminum support is preferably 0.4 to 0.6 μm, and is controlled by a combination of hydrochloric acid concentration, current density, and electric quantity in the roughening treatment. I can do it.

((A) Photopolymerization initiator)
The photopolymerization initiator is a compound capable of initiating polymerization of the (C) polymerizable ethylenically unsaturated bond-containing compound by image exposure, and the photopolymerizable photosensitive layer according to the present invention is a photopolymerization initiator. As an iron arene compound.

  The metal arene compound according to the present invention is a compound represented by the following general formula (a).

Formula (a) [AMB] ⁺ X ⁻
In the formula, A represents a cyclopentadienyl group or an alkyl-substituted cyclopentadienyl group. In the formula, B represents an aromatic group. In the formula, X ⁻ represents an anion. M represents a metal atom such as iron, nickel or cobalt.

Specific examples of the aromatic ring of the aromatic group include benzene, toluene, xylene, cumene, naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, biphenyl, fluorene and the like. Examples of X ⁻ include PF ₆ ⁻ , BF ₄ ⁻ , SbF ₆ ⁻ , AlF ₄ ⁻ , CF ₃ SO ₃ ^{− and the} like.

  Desirable metal arene compounds are iron arene compounds, chromium arene compounds, manganese arene compounds, cobalt arene compounds, nickel arene compounds, etc. Among them, iron arene compounds are preferred in terms of sensitivity.

  Examples of the iron arene 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 , Η-xylene- (η-cyclopentadienyl) iron • hexafluorophosphate, η-benzene- (η-cyclopentadienyl) iron • tetrafluoroborate, and the like.

  The content of the metal arene compound in the photopolymerizable photosensitive layer is preferably 0.1% by mass to 20% by mass, and particularly preferably 0.5% by mass to 10% by mass with respect to the photosensitive layer.

  Examples of the photopolymerization initiator that can be used in combination include titanocene compounds, monoalkyltriarylborate compounds, and trihaloalkyl compounds.

  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- , 3,4,5,6-pentafluorophenyl, bis (methylcyclopentadienyl) -Ti-bis-2,3,5,6-tetrafluorophenyl, bis (methylcyclopentadienyl) -Ti-bis -2,6-difluorophenyl (IRUGACURE 727L: manufactured by Ciba Specialty Chemicals), bis (cyclopentadienyl) -bis (2,6-difluoro-3- (pyridin-1-yl) phenyl) titanium (IRUGACURE 784: 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) titanium and the like It is below.

  Examples of the monoalkyl triaryl borate compound include compounds described in JP-A-62-150242 and JP-A-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-tert-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.

  In addition, any photopolymerization initiator 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 British Patent 1,459,563.

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

  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 and uranyl compounds, JP-B-59-1281, 61-9621 and JP-A-60-60104 Triazine derivatives; organic peroxides described in JP-A-59-1504 and JP-A-61-243807; JP-B-43-23684, JP-A-44-6413, JP-A-44-6413, JP-A-47-1604, and US patents Diazonium compounds described in US Pat. No. 3,567,453; organic azide compounds described in US Pat. Nos. 2,848,328 and 2,852,379 and 2,940,853; O-quinonediazides described in JP-A Nos. 13109, 38-18015 and 45-9610; JP-B-55-39162, JP-A-59-14023 and “Macromolecules”, Vol. 10, 1307 Various onium compounds described on page 1977; azo compounds described in JP-A-59-142205 Compound: JP-A-1-54440, European Patents 109,851, 126,712 and “Journal of Imaging Science (J. Imag. Sci.)”, Vol. 30, 174 (1986) (Oxo) sulfonium organoboron complexes described in Japanese Patent Application Nos. 4-56831 and 4-89535; "Coordination Chemistry Review", 84, 85-277 (1988) and Transition metal complexes containing a transition metal such as ruthenium described in JP-A-2-182701; 2,4,5-triarylimidazole dimer described in JP-A-3-209477; carbon tetrabromide, JP-A-59 Organohalogen compounds described in No. -107344, and the like.

(Trihaloalkyl compound)
The photopolymerizable photosensitive layer according to the present invention preferably contains a trihaloalkyl compound. A trihaloalkyl compound is a compound having a trihaloalkyl group, particularly when an addition-polymerizable ethylenically unsaturated bond-containing compound containing a group that can be oxidized with light is included as an addition-polymerizable ethylenically unsaturated bond-containing compound. Preferably used. As a compound containing a trihaloalkyl group, a compound containing chlorine or bromine is particularly suitable.

  As the trihaloalkyl group, a trihalomethyl group is preferable, and it is preferable that the trihaloalkyl group is bonded to an aromatic carbocycle or a heterocycle directly or via a continuously conjugated chain. Preferred are those having a triazine ring having two trihalomethyl groups as a mother nucleus, particularly the compounds described in EP-A-137452, DE-A-2118259 and 2243621. These compounds exhibit strong light absorption in the near ultraviolet region, for example, 350 to 400 nm. Combination initiators that do not absorb themselves or absorb very little light in the spectral region of the copying light, for example trihalomethyltriazines containing substituents with short electronic systems or aliphatic substituents that allow mesomeries; Is also appropriate. Likewise suitable are compounds having different basic skeletons and absorbing light in the short-wave ultraviolet region, such as phenyl trihalomethyl sulfone or phenyl trihalomethyl ketone, such as phenyl tribromomethyl sulfone.

((B) polymer binder)
Examples of the polymer binder according to the present invention include an acrylic polymer, polyvinyl butyral resin, polyurethane resin, polyamide resin, polyester resin, epoxy resin, phenol resin, polycarbonate resin, polyvinyl butyral resin, polyvinyl formal resin, shellac, and the like. Natural resins can be used. Two or more of these may be used in combination.

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

  Specific examples of alkyl methacrylates and alkyl 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 In addition to unsubstituted alkyl esters such as decyl acid, undecyl acrylate and dodecyl acrylate, cyclic alkyl esters such as cyclohexyl methacrylate and cyclohexyl acrylate Substituted alkyl esters such as benzyl methacrylate, 2-chloroethyl methacrylate, N, N-dimethylaminoethyl methacrylate, glycidyl methacrylate, benzyl acrylate, 2-chloroethyl acrylate, N, N-dimethylaminoethyl acrylate, and glycidyl acrylate Also mentioned.

  Furthermore, the polymer binder according to the present invention can use monomers described in the following (1) to (14) as other copolymerization monomers.

  1) Monomers having an aromatic hydroxyl group, such as o- (or p-, m-) hydroxystyrene, o- (or p-, m-) hydroxyphenyl acrylate and the like.

  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 and the like.

  3) A monomer having an aminosulfonyl group, such as m- (or p-) aminosulfonylphenyl methacrylate, m- (or p-) aminosulfonylphenyl acrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- (p -Aminosulfonylphenyl) acrylamide and the like.

  4) Monomers having a sulfonamide group, such as N- (p-toluenesulfonyl) acrylamide, N- (p-toluenesulfonyl) methacrylamide and the like.

  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-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide and the like.

  6) Monomers containing fluorinated alkyl groups such as trifluoroethyl acrylate, trifluoroethyl methacrylate, tetrafluoropropyl methacrylate, hexafluoropropyl methacrylate, octafluoropentyl 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 and the like.

  8) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl benzoate and the like.

  9) Styrenes such as styrene, methyl styrene, chloromethyl styrene and the like.

  10) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, and phenyl vinyl ketone.

  11) Olefins such as ethylene, propylene, i-butylene, butadiene, isoprene and the like.

  12) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine and the like.

  13) Monomers having a cyano group, such as acrylonitrile, methacrylonitrile, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, o- (or m-, p-) cyanostyrene.

  14) A monomer having an amino group, such as N, N-diethylaminoethyl methacrylate, N, N-dimethylaminoethyl acrylate, N, N-dimethylaminoethyl methacrylate, polybutadiene urethane acrylate, N, N-dimethylaminopropyl acrylamide, N, N-dimethylacrylamide, acryloylmorpholine, Ni-propylacrylamide, N, N-diethylacrylamide and the like.

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

  The vinyl polymer can be produced by ordinary solution polymerization. It can also be produced by bulk polymerization or suspension polymerization. The polymerization initiator is not particularly limited, and examples thereof include azobis-based radical generators such as 2,2′-azobisisobutyronitrile (AIBN), 2,2′-azobis (2-methylbutyro). Nitrile) and the like. Moreover, the usage-amount of these polymerization initiators is 0.05-10.0 mass parts normally with respect to 100 mass parts of whole monomers used for forming a copolymer (preferably 0.1-5 mass). Part). Examples of the solvent used for the solution polymerization include ketone-based, ester-based, and aromatic-based organic solvents, among which toluene, ethyl acetate, benzene, methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, and the like. In general, a good solvent for an acrylic polymer is used, and a solvent having a boiling point of 60 to 120 ° C. is particularly preferable. In the case of solution polymerization, the above solvent is used, and the reaction temperature is usually 40 to 120 ° C. (preferably 60 to 110 ° C.) and the reaction time is usually 3 to 10 hours (preferably 5 to 8 hours). it can. After completion of the reaction, the solvent is removed to obtain a copolymer. Further, the double bond introduction reaction described later can be carried out without removing the solvent.

  The molecular weight of the resulting copolymer can be adjusted by adjusting the solvent used and the reaction temperature. The solvent, reaction temperature, and the like used to obtain the desired molecular weight copolymer can be appropriately determined depending on the monomer used. Moreover, the molecular weight of the copolymer obtained can also be adjusted by mixing a specific solvent with the said solvent. Examples of such solvents include mercaptans (eg, n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, mercaptoethanol, etc.), carbon tetrachloride (eg, carbon tetrachloride, butyl chloride, propylene chloride). Etc.). The ratio of mixing these solvents with the solvent used in the above reaction can be appropriately determined depending on the monomer, solvent, reaction conditions, etc. used in the reaction.

  Furthermore, the polymer binder according to the present invention 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. In addition, an unsaturated bond-containing vinyl copolymer obtained by adding a compound having a (meth) acryloyl group and an isocyanate group in the molecule to a 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 (meth) acrylic isocyanate, 2- (meth) acryloyloxyethyl isocyanate and the like can be mentioned.

  A known method can be used for the addition reaction of 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. For example, the reaction temperature is 20 to 100 ° C., preferably 40 to 80 ° C., particularly preferably at the boiling point (under reflux) of the solvent used, and the reaction time is 2 to 10 hours, preferably 3 to 6 hours. Can do. Examples of the solvent to be used include those used in the polymerization reaction of the vinyl copolymer. In addition, after the polymerization reaction, the solvent can be used as it is for the introduction reaction of the alicyclic epoxy group-containing unsaturated compound without removing the solvent. The reaction can be performed in the presence of a catalyst and a polymerization inhibitor as necessary.

  Here, the catalyst is preferably an amine-based or ammonium chloride-based material, and specifically, the amine-based material is triethylamine, tributylamine, dimethylaminoethanol, diethylaminoethanol, methylamine, ethylamine, n-propylamine. , Isopropylamine, 3-methoxypropylamine, butylamine, allylamine, hexylamine, 2-ethylhexylamine, benzylamine, and the like, and ammonium chloride-based substances include triethylbenzylammonium chloride and the like.

  When using these as a catalyst, what is necessary is just to add in 0.01-20.0 mass% with respect to the alicyclic epoxy group containing unsaturated compound to be used. In addition, as polymerization inhibitors, hydroquinone, hydroquinone monomethyl ether, tert-butyl hydroquinone, 2,5-di-tert-butyl hydroquinone, methyl hydroquinone, p-benzoquinone, methyl-p-benzoquinone, tert-butyl-p-benzoquinone 2,5-diphenyl-p-benzoquinone and the like, and the amount used is 0.01 to 5.0% by mass with respect to the alicyclic epoxy group-containing unsaturated compound to be used. The progress of the reaction may be determined by measuring the acid value of the reaction system and stopping the reaction when the acid value becomes zero.

  A known method can be used for the addition reaction of a compound having a (meth) acryloyl group and an isocyanate group in the molecule to a hydroxyl group present in the molecule of the vinyl polymer. For example, the reaction temperature is usually 20 to 100 ° C., preferably 40 to 80 ° C., particularly preferably at the boiling point (under reflux) of the solvent used, and the reaction time is usually 2 to 10 hours, preferably 3 to 6 hours. It can be carried out. Examples of the solvent to be used include solvents used in the polymerization reaction of the polymer copolymer. Further, after the polymerization reaction, the solvent can be used as it is for the introduction reaction of the isocyanate group-containing unsaturated compound without removing the solvent. The reaction can be performed in the presence of a catalyst and a polymerization inhibitor as necessary. Here, the catalyst is preferably a tin-based or amine-based substance, and specific examples include dibutyltin laurate and triethylamine.

  The catalyst is preferably added in the range of 0.01 to 20.0 mass% with respect to the compound having a double bond to be used. In addition, as polymerization inhibitors, hydroquinone, hydroquinone monomethyl ether, tert-butyl hydroquinone, 2,5-di-tert-butyl hydroquinone, methyl hydroquinone, p-benzoquinone, methyl-p-benzoquinone, tert-butyl-p-benzoquinone 2,5-diphenyl-p-benzoquinone and the like, and the amount used is usually 0.01 to 5.0% by mass with respect to the isocyanate group-containing unsaturated compound to be used. The progress of the reaction may be determined by determining the presence or absence of an isocyanato group in the reaction system using an infrared absorption spectrum (IR), and stopping the reaction when the absorption disappears.

  The vinyl polymer having a carboxyl group and a polymerizable double bond in the side chain that can be used in the present invention is preferably 50 to 100% by mass, and 100% by mass in the total polymer binder. It is more preferable.

  The content of the polymer binder in the photopolymerizable photosensitive layer is preferably in the range of 10 to 90% by mass, more preferably in the range of 15 to 70% by mass, and the content in the range of 20 to 50% by mass. This is particularly preferable from the viewpoint of sensitivity.

((C) Polymerizable, ethylenically unsaturated bond-containing compound)
The polymerizable ethylenically unsaturated bond-containing compound according to the present invention is a compound having an ethylenically unsaturated bond that can be polymerized in the molecule, 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 used, and polyfunctional oligomers can be used.

  These polymerizable ethylenically unsaturated bond-containing compounds are not particularly limited. For example, 2-ethylhexyl acrylate, 2-hydroxypropyl acrylate, glycerol acrylate, tetrahydrofurfuryl acrylate, phenoxyethyl acrylate, nonylphenoxyethyl acrylate, tetrahydro Monofunctional acrylic acid esters such as furfuryloxyethyl acrylate, tetrahydrofurfuryloxyhexanolide acrylate, ε-caprolactone adduct of 1,3-dioxane alcohol, 1,3-dioxolane acrylate, or these acrylates. Methacrylic acid, itaconic acid, crotonic acid, maleic acid ester instead of methacrylate, itaconate, crotonate, maleate Diethylene glycol 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- 1,3-dioxane diacrylate, tricyclodecane dimethylol acrylate, tricyclodecane dimethylol acrylate -Bifunctional acrylates such as caprolactone adduct, diglycidyl ether diacrylate of 1,6-hexanediol, or methacrylic acid, itaconic acid, crotonic acid in which these acrylates are replaced with methacrylate, itaconate, crotonate, maleate Maleic esters such as trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, trimethylolethane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexa Acrylate, ε-caprolactone adduct of dipentaerythritol hexaacrylate, Multifunctional acrylic acid ester acid such as rogalol triacrylate, propionic acid / dipentaerythritol triacrylate, propionic acid / dipentaerythritol tetraacrylate, hydroxypivalylaldehyde-modified dimethylolpropane triacrylate, or acrylate of these acrylates, itaconate , Methacrylic acid, itaconic acid, crotonic acid, maleic acid ester, etc., instead of crotonate and maleate.

(Polymerizable ethylenically unsaturated bond-containing compound containing a group that can be oxidized by light)
The polymerizable ethylenically unsaturated bond-containing compound used in the photopolymerizable photosensitive layer according to the present invention is an addition-polymerizable ethylenically unsaturated bond-containing compound containing at least one group capable of being oxidized by light. It is preferable.

  Particularly preferred are addition polymerizable compounds containing at least one photooxidizable group and at least one urethane group in the molecule. Suitable photooxidizable groups are in particular thio groups, thioether groups, ureido groups, amino groups and enol groups which may be members of the heterocyclic ring. Examples of these groups are triethanolamino group, triphenylamino group, thioureido group, imidazolyl group, oxazolyl group, thiazolyl group, acetylacetonyl residue, N-phenylglycine residue and ascorbic acid residue. Preference is given to addition-polymerizable compounds containing a tertiary amino group and a thioether group.

  Examples of the compound containing a photooxidizable group are described in European Patent Publication Nos. 287,818, 353,389 and 364,735. Preferred among the compounds described therein are those containing a ureido group and / or a urethane group in addition to the tertiary amino group.

  Examples of the compound having at least one photooxidizable group and at least one urethane group are described in JP-A Nos. 63-260909, 2666949, 6-35189, and 2001-125255. Can be mentioned.

  Furthermore, it is preferable to use a reaction product 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.

  Examples of the polyhydric alcohol containing a tertiary amino group in the molecule include triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, Nn-butyldiethanolamine, N-tert. -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 (iso-propyl) amino-2,3-propanediol, 3- (N-methyl-N-benzylamino) -1, Although 2-propanediol etc. are mentioned, it is not limited to this.

  Examples of the diisocyanate compound 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. Limited to Not. Although it does not specifically limit as a compound containing the ethylenic double bond which can be addition-polymerized with a hydroxyl group in a molecule | numerator, Preferably, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, 2- Examples include hydroxypropylene-1,3-dimethacrylate and 2-hydroxypropylene-1-methacrylate-3-acrylate.

  These reactions can be carried out in the same manner as a method for synthesizing urethane acrylate by a reaction of a normal diol compound, diisocyanate compound, and hydroxyl group-containing acrylate compound.

  Specific examples of reaction products of polyhydric alcohols containing tertiary amino groups in the molecule, diisocyanate compounds, and compounds containing ethylenic double bonds capable of addition polymerization with hydroxyl groups in the molecule are shown below. Shown in

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) Product M-5: Reaction product of N-methyldiethanolamine (1 mol), tolylene-2,4-diisocyanate (2 mol), 2-hydroxypropylene-1,3-dimethacrylate (2 mol) An acrylate or an alkyl acrylate described in JP-A-1-105238 and JP-A-2-127404 can be used.

(Other polymerizable, ethylenically unsaturated bond-containing compounds)
Prepolymers can also be used 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 be preferably 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 prepolymers 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, 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, trimethylol Polyester obtained by introducing (meth) acrylic acid into a polyester obtained by combining polyhydric alcohols such as propane, pentaerythritol, sorbitol, 1,6-hexanediol, 1,2,6-hexanetriol Acrylates; for example, epoxy acrylates in which (meth) acrylic acid is introduced into an epoxy resin such as bisphenol A, epichlorohydrin, (meth) acrylic acid, phenol novolac, epichlorohydrin, (meth) acrylic acid; Acid / tolylene diisocyanate / 2-hydroxyethyl acrylate, polyethylene glycol / tolylene diisocyanate / 2-hydroxyethyl acrylate, hydroxyethylphthalyl methacrylate / xylene diisocyanate, 1,2-polybutadiene glycol / tolylene diisocyanate / 2-hydroxyethyl acrylate , Trimethylolpropane, propylene glycol, tolylene diisocyanate, 2-hydroxyethyl acrylate In addition, 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 (meth) acryloyl in oil-modified alkyd resins Examples include prepolymers such as alkyd-modified acrylates and spirane resin acrylates having a group introduced therein.

  Further, as the polymerizable ethylenically unsaturated bond-containing compound according to the present invention, phosphazene monomer, triethylene glycol, isocyanuric acid EO (ethylene oxide) modified diacrylate, isocyanuric acid EO modified triacrylate, dimethylol tricyclodede Examples include candiacrylate, trimethylolpropane acrylic acid benzoate, alkylene glycol type acrylic acid modified / urethane modified acrylate monomers and addition polymerizable oligomers and prepolymers having structural units formed from the monomers. be able to.

  Furthermore, the polymerizable ethylenically unsaturated bond-containing compound according to the present invention includes a phosphoric ester compound containing at least one (meth) acryloyl group. The compound is not particularly limited as long as it is a compound in which at least part of the hydroxyl group of phosphoric acid is esterified and has a (meth) acryloyl group.

  In addition, JP-A-58-212994, 61-6649, 62-46688, 62-48589, 62-173295, 62-187092, 63- No. 67189, JP-A-1-244891, and the like. Furthermore, “11290 Chemical Products”, Chemical Industry Daily, p. 286-p. 294, “UV / EB Curing Handbook (raw material)”, Kobunshi Shuppankai, 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.

  The photosensitive lithographic printing plate material according to the present invention preferably contains the polymerizable, ethylenically unsaturated bond-containing compound in the range of 1.0 to 80.0% by mass of the photosensitive layer, and more preferably. Is in the range of 3.0 to 70.0 mass%.

(Protective layer)
A protective layer is preferably provided on the upper side of the photopolymerizable photosensitive layer according to the present invention. The protective layer (oxygen barrier layer) preferably has high solubility in a developer (alkaline aqueous solution).

  The material constituting the protective layer is preferably polyvinyl alcohol, polysaccharide, polyvinyl pyrrolidone, polyethylene glycol, gelatin, glue, casein, hydroxyethyl cellulose, carboxymethyl cellulose, methyl cellulose, hydroxyethyl starch, gum arabic, sucrose octaacetate, ammonium alginate , Sodium alginate, polyvinylamine, polyethylene oxide, polystyrene sulfonic acid, polyacrylic acid, water-soluble polyamide and the like. These compounds can be used alone or in combination of two or more as a protective layer coating composition. A particularly preferred compound is polyvinyl alcohol.

  In order to prepare the protective layer coating composition, the above-mentioned material can be dissolved in a suitable solvent to form a coating solution, which is coated on the photopolymerizable photosensitive layer according to the present invention and dried. Thus, a protective layer can be formed. The thickness of the protective layer is preferably from 0.1 to 5.0 μm, particularly preferably from 0.5 to 3.0 μm. The protective layer can further contain a surfactant, a matting agent and the like as required.

  As the method for coating the protective layer, the known coating methods mentioned above for coating the photosensitive layer can be suitably used. The drying temperature of the protective layer is preferably lower than the drying temperature of the photosensitive layer, preferably the difference from the photosensitive layer drying temperature is 10 ° C. or more, more preferably 20 ° C. or more, and the upper limit is about 50 ° C. at most. .

  Moreover, it is preferable that the drying temperature of a protective layer is lower than the glass transition temperature (Tg) of the binder which a photosensitive layer contains. The difference between the drying temperature of the protective layer and the glass transition temperature (Tg) of the binder contained in the photosensitive layer is preferably 20 ° C. or higher, more preferably 40 ° C. or higher, and the upper limit is about 60 ° C. at most.

(Color material)
The photopolymerizable photosensitive layer according to the present invention may include a color material that absorbs image exposure light as necessary. Examples of the coloring material include cyanine, phthalocyanine, merocyanine, porphyrin, spiro compound, ferrocene, fluorene, fulgide, imidazole, perylene, phenazine, phenothiazine, polyene, azo compound, diphenylmethane, triphenylmethane, polymethine acridine, coumarin, coumarin derivative, Examples include ketoalcohol borate complexes such as ketocoumarin, quinacridone, indigo, styryl, pyrylium compound, pyromethene compound, pyrazolotriazole compound, benzothiazole compound, barbituric acid derivative, thiobarbituric acid derivative, and further European Patent No. 568,993 , U.S. Pat. Nos. 4,508,811, 5,227,227, JP-A-2001-125255, JP-A-11-271969, and the like. It is.

(Dye having an absorption maximum wavelength of 350 to 550 nm)
The photopolymerizable photosensitive layer according to the present invention preferably contains a dye having an absorption maximum wavelength of 350 to 550 nm.

  That is, on an aluminum support, (A) a photopolymerization initiator, (B) a polymer binder, (C) a polymerizable, ethylenically unsaturated bond-containing compound, and (D) an absorption maximum wavelength of 350 to 550 nm. In the plate making method of a photosensitive lithographic printing plate in which a photosensitive lithographic printing plate having a photopolymerizable photosensitive layer containing a certain dye is subjected to image exposure and then developed with a developer comprising an alkaline aqueous solution, the alkaline aqueous solution is the above-mentioned general aqueous solution. A method for making a photosensitive lithographic printing plate comprising a compound represented by formula (1), wherein the photopolymerizable photosensitive layer contains a metal arene compound as the photopolymerization initiator (A) is preferred. It is an aspect.

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

  Among these sensitizing dyes, for example, coumarin derivatives of B-1 to B-22 in JP-A-8-129258, coumarin derivatives of D-1 to D-32 in JP-A-2003-21901, and JP-A-2002. No. 1-363206, 1 to 21 coumarin derivatives, JP 2002-363207 A to 40 coumarin derivatives, JP 2002-363208 A to 34 coumarin derivatives, JP 2002-363209 A, 1 to 56 coumarin derivatives and the like can be preferably used. Specific examples of the dye that can be used in the present invention are shown below.

(Plate making method)
In the present invention, the photosensitive lithographic printing plate is exposed with a laser in the ultraviolet region of 350 nm to 550 nm. The following can be used as an available laser light source having a wavelength of 350 to 550 nm. Ar ion laser (364 nm, 351 nm), Kr ion laser (356 nm, 351 nm), He—Cd laser (441 nm) as gas laser, Nd: YAG (YVO ₄ ) and SHG crystal × 2 combinations in combination as solid laser (355 nm), a combination of Cr: LiSAF and SHG crystal (430 nm), as a semiconductor laser system, a combination of KNbO ₃ , ring resonator (430 nm), waveguide type wavelength conversion element and AlGaAs, InGaAs semiconductor (380 nm to 450 nm) ), A combination of a waveguide type wavelength conversion element, AlGaInP, and an AlGaAs semiconductor (300 nm to 350 nm), AlGaInN (350 nm to 450 nm), and N ₂ laser (337 nm, pulse 0.1 to 10 mJ) as a pulse laser, XeF ( 35 1 nm, pulse 10 to 250 mJ), FD-YAG laser (532 nm), and the like. Among these, an AlGaInN semiconductor laser (commercially available InGaN-based semiconductor laser 400 to 410 nm) is preferable in terms of wavelength characteristics and cost.

  Laser exposure is suitable for direct writing without using a mask material because light exposure can be performed in the form of a beam according to image data. 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 the main scanning and the movement of the laser light is the 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 a part or all of the optical system. Sub scanning is performed in the axial direction by linearly moving all of them in parallel with the drum axis. In plane scanning, a laser beam main scan is performed by combining a polygon mirror, a galvanometer mirror, and an fθ lens, and a sub-scan 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.

(Automatic processor)
In the plate making method of the present invention, a method of developing a photosensitive lithographic printing plate material using an automatic developing machine is a preferable embodiment because the effects of the present invention are effective.

  The automatic developing machine is preferably provided with a mechanism for automatically replenishing a required amount of replenisher to the developing bath, and preferably provided with a mechanism for discharging a developer exceeding a certain amount, preferably the developing bath. Is provided with a mechanism for automatically replenishing the required amount of water, preferably a mechanism for detecting the plate passing, preferably a mechanism for estimating the processing area of the plate based on the detection of the plate passing And preferably a mechanism for controlling the replenishment amount and / or replenishment timing of replenisher and / or water to be replenished based on the detection of the plate and / or the estimation of the processing area. Preferably, a mechanism for controlling the temperature of the developer is provided, preferably a mechanism for detecting the pH and / or conductivity of the developer is provided, preferably the pH and / or conductivity of the developer. Mechanism for controlling the replenishment amount and / or replenishment timing of replenishment solution and / or water tries to refill the original has been granted.

  The automatic processor may have a pretreatment unit that immerses the plate in the pretreatment liquid before the development step. The pretreatment unit is preferably provided with a mechanism for spraying the pretreatment liquid onto the plate surface, and preferably provided with a mechanism for controlling the temperature of the pretreatment liquid to an arbitrary temperature of 25 ° C to 55 ° C. A mechanism for rubbing the plate surface with a roller-like brush is preferably provided. Moreover, water etc. are used as this pretreatment liquid.

(Post-processing)
The developed plate is subjected to post-treatment with rinse water containing a washing water, a surfactant or the like, a finisher mainly composed of gum arabic or a starch derivative, or a protective gum solution, and then subjected to printing.

  These post-processing are generally performed using an automatic developing machine including a developing unit and a post-processing unit.

  As the post-treatment liquid, a method of spraying from a spray nozzle or a method of immersing and conveying in a treatment tank filled with the treatment liquid is used. There is also known a method in which a small amount of washing water after development is supplied to the plate surface and washed, and the waste solution is reused as dilution water for the developer stock solution. In such automatic processing, processing can be performed while each replenisher is replenished with each replenisher according to the processing amount, operating time, and the like. In addition, a so-called disposable processing method in which treatment is performed with a substantially unused post-treatment liquid can also be applied. The lithographic printing plate obtained by such processing is loaded on an offset printing machine and used for printing a large number of sheets.

  In the plate making method of the present invention, in the case of a photosensitive lithographic printing plate material having an overcoat layer, a plate making method including a step of washing with pre-development washing water is a preferred embodiment.

(printing)
The photosensitive lithographic printing plate material is processed by the plate making method of the present invention and then subjected to printing.

  Printing can be performed using a general lithographic printing machine.

  In recent years, the printing industry has been screaming for environmental conservation, and in printing inks, inks that do not use petroleum-based volatile organic compounds (VOC) have been developed and are becoming popular. This is particularly noticeable when the printing inks are used. Examples of environmentally friendly printing inks include soybean oil ink “Naturalis 100” manufactured by Dainippon Ink and Chemicals, VOC zero ink “TK Hi-Echo NV” manufactured by Toyo Ink, and process ink “Soyselbo” manufactured by Tokyo Ink. It is done.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, the aspect of this invention is not limited to this. In the examples, “parts” represents “parts by mass” unless otherwise specified.

(Binder synthesis)
(Synthesis of acrylic copolymer 1)
In a three-necked flask under a nitrogen stream, 30 parts of methacrylic acid, 50 parts of methyl methacrylate, 20 parts of ethyl methacrylate, 500 parts of isopropyl alcohol and 3 parts of α, α'-azobisisobutyronitrile are placed in a nitrogen stream. The reaction was carried out in an oil bath at 0 ° C. for 6 hours. Then, after refluxing at the boiling point of isopropyl alcohol for 1 hour, 3 parts of triethylammonium chloride and 25 parts of glycidyl methacrylate were added and reacted for 3 hours to obtain an acrylic copolymer 1. The weight average molecular weight measured using GPC was about 35,000, and the glass transition temperature (Tg) measured using DSC (differential thermal analysis) was about 85 ° C.

(Production of support)
An aluminum plate (material 1050, tempered H16) having a thickness of 0.3 mm was immersed in a 5% aqueous sodium hydroxide solution maintained at 65 ° C., degreased for 1 minute, and then washed with water. This degreased aluminum plate was neutralized by dipping in a 10% aqueous hydrochloric acid solution maintained at 25 ° C. for 1 minute, and then washed with water. Next, the aluminum plate was subjected to electrolytic surface roughening with an alternating current for 60 seconds under conditions of 25 ° C. and a current density of 100 A / dm ^{2 in} a 0.3% by mass nitric acid aqueous solution, and then kept at 60 ° C. Desmutting treatment was performed for 10 seconds in a 5% aqueous sodium hydroxide solution. The surface-roughened aluminum plate subjected to desmut treatment was anodized in a 15% sulfuric acid solution at 25 ° C., a current density of 10 A / dm ² , and a voltage of 15 V for 1 minute. Furthermore, after the anodic acid value treatment, a surface treatment was performed in a polyvinyl phosphonic acid aqueous solution at 75 ° C. for 20 seconds to prepare a support. The dry weight of polyvinylphosphonic acid was 8 mg / m ² , and the center line average roughness (Ra) of the surface was 0.65 μm.

(Preparation of photosensitive lithographic printing plate material 1)
On the support, a photopolymerizable photosensitive layer coating solution 1 having the following composition was applied with a wire bar so as to be 1.5 g / m ² when dried, and dried at 95 ° C. for 1.5 minutes. A coated sample was obtained.

(Photopolymerizable photosensitive layer coating solution 1)
Addition-polymerizable ethylenic double bond-containing monomer 1M-3 (above) 25.0 parts Addition-polymerizable ethylenic double bond-containing monomer 2NK ester 4G (polyethylene glycol dimethacrylate manufactured by Shin-Nakamura Chemical) 25.0 parts Polymerization initiator I-1 4.0 parts Trihaloalkyl compound CI-1 2.0 parts Spectral sensitizing dye D-1 (above) 3.0 parts Acrylic copolymer 1 40.0 parts N- Phenylglycine benzyl ester 4.0 parts Phthalocyanine pigment (MHI454: manufactured by Gokoku Dye) 6.0 parts 2-t-butyl-6- (3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methyl Phenyl acrylate (Sumilyzer GS: manufactured by Sumitomo 3M) 0.5 part Fluorine-based surfactant (F-178K; manufactured by Dainippon Ink & Co.) 0.5 part Lohexanone 820 parts M-3: Nn-butyldiethanolamine (1 mol), 1,3-bis (1-isocyanato-1-methylethyl) benzene (2 mol), 2-hydroxypropylene-1-methacrylate-3 -Reaction product of acrylate (2 mol), weight average molecular weight: 54000
Acid value: 80 mgKOH / g
On the photopolymerization photosensitive layer coating sample, an oxygen barrier layer coating solution having the following composition was coated with an applicator so as to be 1.8 g / m ² when dried, and dried at 75 ° C. for 1.5 minutes. A photosensitive lithographic printing plate material (plate material) 1 having an oxygen blocking layer on the photosensitive layer was prepared.

(Oxygen barrier coating liquid)
Polyvinyl alcohol (GL-05: Nippon Synthetic Chemical Co., Ltd.) 70 parts Polyvinylpyrrolidone (K-30: BAFS Co., Ltd.) 30 parts Surfactant (Surfinol 465: Nissin Chemical Industry Co., Ltd.) 0.5 part Water 900 parts (Preparation of photosensitive lithographic printing plate material 2)
Using the photopolymerizable photosensitive layer coating solution 2 in which the spectral sensitizing dye D-1 of the photopolymerizable photosensitive layer coating solution 1 is changed to D-5, the same method as for the photosensitive lithographic printing plate material 1 is used. A photosensitive lithographic printing plate material (plate material) 2 was prepared.

(Image formation)
The produced photosensitive lithographic printing plate material (plate material) 1 uses a CTP exposure apparatus (Tigercat: manufactured by ECRM) equipped with an FD-YAG laser light source, and the area ratio of the image part and the non-image part is 1: Exposure energy: 200 μJ / cm ² , image exposure at a resolution of 2400 dpi (dpi represents the number of dots per 2.54 cm) (exposure pattern is 100% image area, 175 LPI 50%, 5, 4, 3, 2, 1% square dots were used).

The produced photosensitive lithographic printing plate material (plate material) 2 is an image portion, a non-image portion, using a plate setter (Tigercat: a modified product manufactured by ECRM) equipped with a light source having a laser of 405 ± 5 nm and 30 mW. Image exposure with an exposure energy of 50 μJ / cm ² and a resolution of 2400 dpi (same as above) so that the surface area ratio is 1: 9 (exposure pattern is 100% image portion, 175 LPI 50%, 5, 4, 3, 2 1% square dots were used).

Next, a preheating part that is heated so that the plate surface temperature becomes 90 to 120 ° C., a pre-water washing part that removes the oxygen blocking layer before development, a developing part filled with a developer having the following composition, and a developer adhering to the plate surface are removed. About 100 ml / m ² with a CTP automatic developing machine (PHW32-V: manufactured by Technigraph) equipped with a gum solution (GW-3: manufactured by Mitsubishi Chemical Co., Ltd., twice diluted) for protecting the water washing section and the image area. Then, the developer was replenished so that a development process of 3000 m ² was performed to obtain a lithographic printing plate.

  The time during which the photosensitive lithographic printing plate is in contact with the developer is defined as the development time, and the development time using the automatic processor is 25 seconds.

(Preparation of developer)
The developer was adjusted as follows. Table 1 shows the content of the compound of the general formula (1) and the kind and amount of the surfactant.

Developers 1 to 49: (1000 ml aqueous solution formulation)
Compound of general formula (1) Amount described in Table 1 Surfactant Amount described in Table 1 Potassium hydroxide Addition amount to become the following pH The remaining component is water pH 12.3

(Evaluation of sludge contamination and sludge amount)
The prepared printing plate was developed 3000 m ² so that the area ratio of the image area to the non-image area was 1: 9. As the automatic processor, PHW32-V manufactured by Technigraph was used, and the developer was replenished so as to be 100 ml / m ² . The amount of sludge sludge in the tank after completion of development was confirmed.

○: Almost unacceptable
Δ: Dirt is observed in the developing tank and roller, but it is not transferred to the developed plate.
×: Dirt is observed in the developing tank and roller, and the plate is stained. Measurement of sludge amount:
1000 ml of the developer after continuous processing was collected, and the dry weight (g / 1000 ml) of the precipitate after storage at 40 ° C. for 2 weeks was measured.

(Evaluation of stop dirt prevention)
Each image of the lithographic printing plate produced after the above 3000 m ² treatment is applied to a printing machine (DAIYA1F-1 manufactured by Mitsubishi Heavy Industries, Ltd.), coated paper, dampening water (etching solution SG-51 concentration 1.5% manufactured by Tokyo Ink), Printing was performed using printing ink (soybean oil ink Naturalis 100: manufactured by Dainippon Ink & Chemicals, Inc.). After printing 5000 sheets, the printing press was stopped and left for 1 hour to start printing. Fine dot-like stains generated per 100 cm ² of the printed material were observed with a magnifying glass, and the number of occurrences was counted. If the number of fine dot-like stains generated was 10 or less, it was practically acceptable, and if it was 30 or more, it was determined that there was a practical problem.

  Tables 2 and 3 show the evaluation results obtained as described above. From Tables 2 and 3, it can be seen that in the plate-making method of the present invention, the number of fine spot-like stains is small, the developer is hardly sludged, and the resulting stains are small.

Claims (3)

Photosensitive lithographic plate having a photopolymerizable photosensitive layer containing (A) a photopolymerization initiator, (B) a polymer binder, and (C) a polymerizable, ethylenically unsaturated bond-containing compound on an aluminum support. In the plate making method of a photosensitive lithographic printing plate in which a printing plate is subjected to image exposure and then developed with a developer comprising an alkaline aqueous solution, the alkaline aqueous solution contains a compound represented by the following general formula (1), and the photopolymerizable feeling A method for making a photosensitive lithographic printing plate, wherein the light-sensitive layer contains a metal arene compound as the photopolymerization initiator (A).

[Wherein R ₁ represents the following general formula (2) or —CH ₂ CH ₂ OX, R ₂ represents —CH ₂ COOX or —CH ₂ CH ₂ OX, and X represents a hydrogen atom or an alkali metal. ]

[Wherein, A represents an alkylene group having 1 to 5 carbon atoms which may have a substituent, and X represents a hydrogen atom or an alkali metal. ] 2. The plate making method of a photosensitive lithographic printing plate according to claim 1, wherein the developer contains 0.01% by mass to 5% by mass of the compound represented by the general formula (1). The plate making method of a photosensitive lithographic printing plate according to claim 1 or 2, wherein the alkaline aqueous solution contains a surfactant having a polyoxyethylene group.