JP2007292835A - Processing method for photosensitive lithographic printing plate material, and the photosensitive lithographic printing plate material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a processing method for a photosensitive lithographic printing plate material, suitable for exposure with a laser light of which the emission wavelength is in a range of 350-450 nm, having proper safe light properties, and excellent in printing durability, linearity and printing performance, and to provide a photosensitive lithographic printing plate material used in the same. <P>SOLUTION: The processing method for the photosensitive lithographic printing plate material includes image exposure and development of the photosensitive lithographic printing plate material, having on a support a photosensitive layer that contains an addition-polymerizable ethylenic double bond-containing compound; a photopolymerization initiator and a polymer binder, wherein the photosensitive layer further contains titanium oxide particles and a polyhalogenated compound, capable of initiating polymerization under actinic ray, having a wavelength shorter than the wavelength of the exposure light used for the image exposure, and wherein the processing method includes a step of exposure with actinic ray, having a wavelength shorter than the wavelength of the exposure light used for the image exposure after the development. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a method for processing a photosensitive lithographic printing plate material used in a computer-to-plate system (hereinafter referred to as CTP) and a photosensitive lithographic printing plate material, and is particularly sensitive to exposure with a laser beam having a wavelength of 350 to 450 nm. The present invention relates to a lithographic printing plate material and a method for processing the photosensitive lithographic printing plate material.

  In recent years, in a printing plate manufacturing technique for offset printing, CTP for directly recording digital image data on a photosensitive lithographic printing plate material with a laser light source has been developed and is in practical use.

  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 Documents 1 and 2.)

  Further, in a negative type image forming material provided with an image recording layer containing an infrared absorber, a radical generator, a radical polymerizable compound, and a binder polymer, the material is exposed to an infrared laser, and then the material is heated to a temperature of 60 to 120 ° C. An example of heating for 1 to 20 seconds in a range and performing a heat treatment after exposure is known, and as the radical generator, for example, a triazine compound having a trihalomethyl group is known (see Patent Document 3). ). According to such a method, although a lithographic printing plate having a relatively high printing durability can be obtained, there is a problem that a heat treatment after exposure is necessary.

  On the other hand, there is known a printing plate material capable of image exposure with a laser having a wavelength of 390 nm to 430 nm, which has improved safe light properties from the viewpoint of handleability of the printing plate.

Then, a high-power and small-sized blue-violet laser with a wavelength of 390 to 430 nm can be easily obtained. By developing a photosensitive lithographic printing plate material suitable for this laser wavelength, the bright room has been developed. (See Patent Document 4)
However, these printing plate materials may still have insufficient printing durability. When heat treatment is performed after image exposure to improve printing durability, the size of dots (halftone dots) based on image output data There have been problems such as different sizes of dots (halftone dots) on the printing plate, so-called linearity is insufficient, and smearing of non-image areas during printing.
JP-A-1-105238 JP-A-2-127404 JP 2001-175006 A JP 2001-264978 A

  An object of the present invention is a photosensitive lithographic printing plate material suitable for exposure with a laser beam having an emission wavelength in the range of 350 nm to 450 nm, having good safe light properties, and excellent printing durability, linearity and printing performance. The object is to provide a processing method and a photosensitive lithographic printing plate material used therefor.

The above object of the present invention is achieved by the following means.
1. An image of a photosensitive lithographic printing plate material having a photosensitive layer containing (A) an addition-polymerizable ethylenic double bond-containing compound, (B) a photopolymerization initiator, and (C) a polymer binder on a support. A processing method of exposing and developing, wherein the photosensitive layer further initiates polymerization with (D) titanium oxide particles and (E) an actinic ray having a wavelength less than the wavelength of the exposure light used for the image exposure A photosensitive lithographic printing plate material comprising a polyhalogen compound capable of being exposed to an actinic ray having a wavelength less than that of the exposure light used for image exposure after the development treatment Processing method.
2. 2. The method for processing a photosensitive lithographic printing plate material according to 1, wherein the wavelength of exposure light used for the image exposure is 400 nm or more.
3. 3. The method for processing a photosensitive lithographic printing plate material according to 1 or 2, wherein the wavelength of the actinic ray having a wavelength less than the wavelength of the exposure light used for the image exposure is less than 400 nm.
4. A photosensitive lithographic printing plate material, which is used in the method for processing a photosensitive lithographic printing plate material according to any one of 4.1 to 3.

  According to the present invention, it is suitable for exposure with a laser beam having an emission wavelength in the range of 350 nm to 450 nm, has good safe light properties, excellent printing durability, little dot gain, and linearity and anti-unexposed area contamination prevention. A method for treating a photosensitive lithographic printing plate material having good printing performance and a photosensitive lithographic printing plate material used therefor can be provided.

  Next, the best mode for carrying out the present invention will be described, but the present invention is not limited thereto.

  The present invention relates to a photosensitive lithographic printing having a photosensitive layer containing (A) an addition-polymerizable ethylenic double bond-containing compound, (B) a photopolymerization initiator, and (C) a polymer binder on a support. A processing method in which a plate material is image-exposed and developed, and the photosensitive layer further comprises (D) titanium oxide particles and (E) an actinic ray having a wavelength less than the wavelength of exposure light used for the image exposure And a step of exposing to an actinic ray having a wavelength less than the wavelength of the exposure light used for the image exposure after the development treatment.

  Each component contained in the photosensitive layer of the photosensitive lithographic printing plate material of the present invention will be described.

(Addition-polymerizable ethylenic double bond-containing compound)
The photosensitive layer according to the present invention includes (A) an addition-polymerizable ethylenic double bond-containing compound, (1) a compound having an ethylenic double bond that can be polymerized by image exposure, and (2) an image exposure. And a compound having an ethylenic double bond that can be polymerized by exposure with an actinic ray having a wavelength less than that of the exposure light. The above (1) and (2) may be the same or different.

  Addition-polymerizable ethylenic double bond-containing compounds include general radical-polymerizable monomers and polyfunctional compounds having a plurality of addition-polymerizable ethylenic double bonds commonly used in UV curable resins. Monomers and polyfunctional oligomers can be used. The compound is not limited, but preferred examples include 2-ethylhexyl acrylate, 2-hydroxypropyl acrylate, glycerol acrylate, tetrahydrofurfuryl acrylate, phenoxyethyl acrylate, nonylphenoxyethyl acrylate, tetrahydrofurfuryloxyethyl acrylate, tetrahydro Furfuryloxyhexanolide acrylate, acrylate of ε-caprolactone adduct of 1,3-dioxane alcohol, monofunctional acrylic acid esters such as 1,3-dioxolane acrylate, or these acrylates as methacrylate, itaconate, crotonate, maleate Methacrylic acid, itaconic acid, crotonic acid, maleic acid esters such as ethylene glycol diacrylate , Triethylene glycol diacrylate, pentaerythritol diacrylate, hydroquinone diacrylate, resorcin diacrylate, hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, dipentylate of hydroxypentylate neopentyl glycol, Diacrylate of neopentyl glycol adipate, Diacrylate of ε-caprolactone adduct of neopentyl glycol hydroxypivalate, 2- (2-hydroxy-1,1-dimethylethyl) -5-hydroxymethyl-5-ethyl-1, Ε-caprolactone adduct of 3-dioxane diacrylate, tricyclodecane dimethylol acrylate, tricyclodecane dimethylol acrylate Difunctional acrylic acid esters such as diglycidyl ether diacrylate of 1,6-hexanediol, or methacrylic acid, itaconic acid, crotonic acid, maleic acid ester in which these acrylates are replaced with methacrylate, itaconate, crotonate, maleate, For example, trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, trimethylolethane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, dipentaerythritol Ε-caprolactone adduct of hexaacrylate, pyrogallol triacrylate Polyfunctional acrylic acid esters such as propionic acid / dipentaerythritol triacrylate, propionic acid / dipentaerythritol tetraacrylate, hydroxypivalylaldehyde-modified dimethylolpropane triacrylate, or these acrylates with methacrylate, itaconate, crotonate, Examples thereof include methacrylic acid, itaconic acid, crotonic acid, and maleic acid ester instead of maleate.

  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 singly 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 Chlorates 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, adipine 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 resin, for example, silicone resin acrylates such as polysiloxane acrylate, polysiloxane diisocyanate, 2-hydroxyethyl acrylate, etc., and (meth) acryloyl in oil-modified alkyd resins Examples thereof include prepolymers such as alkyd-modified acrylates having introduced groups and spirane resin acrylates.

  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 phosphate ester compounds 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- 67189, JP-A-1-244891, and the like. Further, “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 the photosensitive layer according to the present invention, an addition-polymerizable ethylenic double bond-containing compound containing a tertiary amino group in the molecule, which is a tertiary amine monomer, is preferably used. 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, JP-A-1-203413, and JP-A-1-197213 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, 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.

  Examples of the compound containing an ethylenic double bond capable of addition polymerization with a hydroxyl group in the molecule include 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxypropylene-1,3. -Dimethacrylate, 2-hydroxypropylene-1-methacrylate-3-acrylate, etc. are mentioned.

  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.

  30-70 mass% of the non-volatile component of a photopolymerizable photosensitive layer is preferable, and, as for the addition amount of the ethylenic double bond containing compound which can perform addition polymerization based on this invention, 40-60 mass% is more preferable.

((B) Photopolymerization initiator)
The photopolymerization initiator according to the present invention is a compound capable of initiating polymerization of (A) a polymerizable ethylenically unsaturated bond-containing compound by exposure light used for image exposure of a photosensitive lithographic printing plate material. For example, biimidazole compounds, iron arene complex compounds, titanocene compounds, iodonium salt derivatives, sulfonium salt derivatives, monoalkyltriaryl borate compounds and the like are preferably used.

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

  In the present invention, it is preferable to contain a hexaarylbiimidazole (HABI, triaryl-imidazole dimer) compound as the biimidazole compound.

  Processes for the production of HABIs are described in DE 1,470,154 and their use in photopolymerizable compositions is described in EP 24,629, EP 107,792, US 4,410,621, EP 215,453 and DE 3, 211 and 312.

  Preferred derivatives are, for example, 2,4,5,2 ′, 4 ′, 5′-hexaphenylbiimidazole, 2,2′-bis (2-chlorophenyl) -4,5,4 ′, 5′-tetraphenylbiimidazole. Imidazole, 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-dimethyl) Xylphenyl) 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.

  The amount of HABI is typically in the range of 0.01 to 30% by weight, preferably 0.5 to 20% by weight, based on the total weight of the non-volatile components of the photosensitive composition.

(Iron arene complex compound)
The iron arene complex compound is a compound represented by the following general formula (a).

Formula (a) [A-Fe-B] ⁺ X ⁻
In the formula, A represents a substituted or unsubstituted cyclopentadienyl group or a cyclohexadienyl group. In the formula, B represents a compound having an aromatic ring. In the formula, X ⁻ represents an anion.

Specific examples of the compound having an aromatic ring include benzene, toluene, xylene, cumene, naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, biphenyl, fluorene, anthracene, and pyrene. Examples of X ⁻ include PF ₆ ⁻ , BF ₄ ⁻ , SbF ₆ ⁻ , AlF ₄ ⁻ , CF ₃ SO ₃ ^{− and the} like. Examples of the substituent of the substituted cyclopentadienyl group or cyclohexadienyl group include alkyl groups such as methyl and ethyl groups, cyano groups, acetyl groups, and halogen atoms.

  It is preferable to contain an iron arene complex compound in the ratio of 0.1-20 mass% with respect to the compound which has a group which can superpose | polymerize, More preferably, it is 0.1-10 mass%.

Specific examples of the iron arene complex compound are shown below.
Fe-1: (η6-benzene) (η5-cyclopentadienyl) iron (2) hexafluorophosphate Fe-2: (η6-toluene) (η5-cyclopentadienyl) iron (2) hexafluorophosphate Fe— 3: (η6-cumene) (η5-cyclopentadienyl) iron (2) hexafluorophosphate Fe-4: (η6-benzene) (η5-cyclopentadienyl) iron (2) hexafluoroarsenate Fe-5 : (Η6-benzene) (η5-cyclopentadienyl) iron (2) tetrafluoroporate Fe-6: (η6-naphthalene) (η5-cyclopentadienyl) iron (2) hexafluorophosphate Fe-7: ( η6-anthracene) (η5-cyclopentadienyl) iron (2) hexafluorophosphate Fe-8: (η6-pyrene) Lopentagenyl) iron (2) hexafluorophosphate Fe-9: (η6-benzene) (η5-cyanocyclopentadienyl) iron (2) hexafluorophosphate Fe-10: (η6-toluene) (η5-acetylcyclopentazinini ) Iron (2) Hexafluorophosphate Fe-11: (η6-cumene) (η5-cyclopentadienyl) Iron (2) Tetrafluoroborate Fe-12: (η6-benzene) (η5-carboethoxycyclohexadienyl) ) Iron (2) hexafluorophosphate Fe-13: (η6-benzene) (η5-1,3-dichlorocyclohexadienyl) iron (2) hexafluorophosphate Fe-14: (η6-cyanobenzene) (η5- Cyclohexadienyl) iron (2) hexafluorophosphate Fe-15: (η6 Acetophenone) (η5-cyclohexadienyl) iron (2) hexafluorophosphate Fe-16: (η6-methylbenzoate) (η5-cyclopentadienyl) iron (2) hexafluorophosphate Fe-17: (η6-benzenesulfone Amido) (η5-cyclopentadienyl) iron (2) tetrafluoroborate Fe-18: (η6-benzamide) (η5-cyclopentadienyl) iron (2) hexafluorophosphate Fe-19: (η6-cyanobenzene ) (Η5-cyanocyclopentadienyl) iron (2) hexafluorophosphate FE-20: (η6-chloronaphthalene) (η5-cyclopentadienyl) iron (2) hexafluorophosphate Fe-21: (η6-anthracene) ) (Η5-cyanocyclopentadienyl) iron (2) Xafluorophosphate Fe-22: (η6-chlorobenzene) (η5-cyclopentadienyl) iron (2) Hexafluorophosphate Fe-23: (η6-chlorobenzene) (η5-cyclopentadienyl) iron (2) Tetrafluoroborate These compounds are described in Dokl. Akd. It can be synthesized by the method described in Nauk SSSR 149 615 (1963).

(Titanocene compound)
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.

(Monoalkyltriaryl borate compound)
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, etc. .

  Examples of the sulfonium salt include triphenylsulfonium tetrafluoroborate, methyldiphenylsulfonium tetrafluoroborate, dimethylphenylsulfonium hexafluorophosphate, 4-butoxyphenyldiphenylsulfonium tetrafluoroborate, 4-chlorophenyldiphenylsulfonium hexafluorophosphate, tri (4- Phenoxyphenyl) sulfonium hexafluorophosphate, di (4-ethoxyphenyl) methylsulfonium hexafluoroarsenate, 4-acetonylphenyldiphenylsulfonium tetrafluoroborate, 4-thiomethoxyphenyldiphenylsulfonium hexafluorophosphate, di (methoxysulfonylphenyl) Methylsulfonium hexafluoroa Timonate, di (nitrophenyl) phenylsulfonium hexafluoroantimonate, di (carbomethoxyphenyl) methylsulfonium hexafluorophosphate, 4-acetamidophenyldiphenylsulfonium tetrafluoroborate, dimethylnaphthylsulfonium hexafluorophosphate, trifluoromethyldiphenylsulfonium tetrafluoro Borate, p- (phenylthiophenyl) diphenylsulfonium hexafluoroantimonate, 10-methylphenoxathinium hexafluorophosphate, 5-methylthiantrenium hexafluorophosphate, 10-phenyl-9,9-dimethylthioxanthenium Hexafluorophosphate, triphenylsulfonium tetrakis (pentaful Rofeniru) it can be mentioned borate.

  Examples of the iodonium salt include diphenyliodonium iodide, diphenyliodonium hexafluoroantimonate, 4-chlorophenyliodonium tetrafluoroborate, di (4-chlorophenyl) iodonium hexafluoroantimonate, diphenyliodonium hexafluorophosphate, diphenyliodonium trifluoroacetate, 4 -Trifluoromethylphenyliodonium tetrafluoroborate, diphenyliodonium hexafluoroazenate, ditolyliodonium hexafluorophosphate, di (4-methoxyphenyl) iodonium hexafluoroantimonate, di (4-methoxyphenyl) iodonium chloride, (4- Methylphenyl) phenyliodonium tetrafluorovolley , Di (2,4-dimethylphenyl) iodonium hexafluoroantimonate, di (4-t-butylphenyl) iodonium hexafluoroantimonate, 2,2′-diphenyliodonium hexafluorophosphate, tricumyldiphenyliodonium tetrakis (penta Fluorophenyl) borate and the like.

  In the present invention, other known photopolymerization initiators may be used in combination as the photopolymerization initiator.

  As content (total amount) of the photoinitiator which concerns on this invention, 0.1-20 mass% is preferable with respect to a photosensitive layer, and 0.5-10 mass% is more preferable.

  In the processing method of the present invention, the wavelength of exposure light used for image exposure is preferably 400 nm or more from the viewpoint of plate material sensitivity, and more preferably 400 to 450 nm. As the photopolymerization initiator when the wavelength of the image exposure light is 400 to 450 nm, in particular, a biimidazole compound, an iron arene complex compound or a titanocene compound, an iodonium salt derivative, or a sulfonium salt derivative is preferably used.

((E) polyhalogen compound)
According to the present invention, (E) the polyhalogen compound capable of initiating polymerization with an actinic ray having a wavelength less than the wavelength of exposure light used for image exposure is less than the wavelength of exposure light used for image exposure after development processing. And (A) a polyhalogen compound capable of initiating polymerization of an ethylenically unsaturated bond-containing compound by exposure in the step of exposing with an actinic ray having a wavelength of (A).

  The polyhalogen compound is preferably a polyhaloacetyl compound, and more preferably a trihaloacetylamide compound. Examples of the polyhaloacetyl compound include a compound represented by the following general formula (10) or more preferably a compound represented by the following general formula (11).

Formula ^{(10) R 11 -C (X} 10) 2 - (C = O) -R 12
In the formula, X ¹⁰ represents a chlorine atom or a bromine atom. R ¹¹ represents a hydrogen atom, a chlorine atom, a bromine atom, an alkyl group, an aryl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group or a cyano group. R ¹² represents a monovalent substituent. R ¹¹ and R ¹² may be bonded to form a ring.

Formula ^{(11) C (X 11)} 3 - (C = O) -Y 10 -R 13
In the formula, X ¹¹ represents a chlorine atom or a bromine atom. R ¹³ represents a monovalent substituent. Y ¹⁰ represents —O— or —NR ¹⁴ —. R ¹⁴ represents a hydrogen atom or an alkyl group. R ¹³ and R ¹⁴ may combine to form a ring.

  Typical specific examples of the compound represented by the general formula (11) are listed below, but the present invention is not limited thereto.

  In the polyhalogen compounds represented by the general formulas (10) and (11), polybromine compounds are more preferable.

  Examples of polyhalogen compounds preferably used in the present invention include trihalomethyltriazine compounds. For example, Wakabayashi et al., Bull. Chem. Soc. Japan, 42, 2924 (1969), for example, 2-phenyl-4,6-bis (trichloromethyl) -S-triazine, 2- (p-chlorophenyl) -4,6-bis (trichloromethyl) -S-triazine, 2- (p-tolyl) -4,6-bis (trichloromethyl) -S-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -S-triazine, 2- (2 ', 4'-dichlorophenyl) -4,6-bis (trichloromethyl) -S-triazine, 2,4,6-tris (trichloromethyl) -S-triazine, 2-methyl-4, 6-bis (trichloromethyl) -S-triazine, 2-n-nonyl-4,6-bis (trichloromethyl) -S-triazine, 2- (α, α, β-trichloroethyl) -4, - bis (trichloromethyl) -S- triazine. In addition, compounds described in British Patent 1388492, for example, 2-styryl-4,6-bis (trichloromethyl) -S-triazine, 2- (4-styrylphenyl) -4,6-bis (trichloromethyl) -S-triazine, 2- (p-methylstyryl) -4,6-bis (trichloromethyl) -S-triazine, 2- (p-methoxystyryl) -4,6-bis (trichloromethyl) -S-triazine , 2- (p-methoxystyryl) -4-amino-6-trichloromethyl-S-triazine, etc., compounds described in JP-A-53-133428, such as 2- (4-methoxy-naphth-1-yl) -4,6-bis-trichloromethyl-S-triazine, 2- (4-ethoxy-naphth-1-yl) -4,6-bis-trichloromethyl-S-tria 2- [4- (2-ethoxyethyl) -naphth-1-yl] -4,6-bis-trichloromethyl-S-triazine, 2- (4,7-dimethoxy-naphth-1-yl)- Examples include 4,6-bis-trichloromethyl-S-triazine, 2- (acenaphtho-5-yl) -4,6-bis-trichloromethyl-S-triazine, and the compounds described in German Patent 3337024. be able to. F.F. C. J. Schaefer et al. Org. Chem. 29, 1527 (1964), such as 2-methyl-4,6-bis (tribromomethyl) -S-triazine, 2,4,6-tris (tribromomethyl) -S-triazine, 2, 4,6-tris (dibromomethyl) -S-triazine, 2-amino-4-methyl-6-tribromomethyl-S-triazine, 2-methoxy-4-methyl-6-trichloromethyl-S-triazine, etc. be able to.

  The content (total amount) of the polyhalogen compound according to the present invention is preferably from 0.1 to 20% by weight, more preferably from 0.3 to 10% by weight, based on the printing layer, from the viewpoint of printing durability.

  The exposure light used in the step of exposing with actinic rays having a wavelength less than that of the exposure light used for image exposure preferably has a wavelength of 400 nm or less. When this wavelength is 400 nm or less, as the polyhalogen compound, a tribromoacetylamide compound, a trichloroacetylamide compound, or a triazine derivative is particularly preferably used.

((C) polymer binder)
Next, the polymer binder will be described.

  Examples of the polymer binder used in the present invention include acrylic polymers, polyvinyl butyral resins, polyurethane resins, polyamide resins, polyester resins, epoxy resins, phenol resins, polycarbonate resins, polyvinyl butyral resins, polyvinyl formal resins, shellacs, and others. 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, in the polymer binder of the present invention, monomers described in the following (1) to (14) can be used 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.

  Furthermore, the polymer binder of 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 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 mass, more preferably in the range of 15 to 70% by mass, and the use in the range of 20 to 50% by mass from the viewpoint of sensitivity. Particularly preferred.

((D) Titanium oxide particles)
The titanium oxide particles according to the present invention are present as particles dispersed in the photosensitive layer, and the particle diameter is preferably 0.001 μm to 10 μm, more preferably 0.01 μm to 1 μm. By allowing titanium oxide and a polyhalogen compound to coexist and undergoing a further exposure step after development, it is possible to provide a processing method for a printing plate material that has excellent anti-stain properties in unexposed areas, low dot gain, and excellent printing durability. .

  As content of a titanium oxide, 0.1 mass%-20 mass% are preferable with respect to a photosensitive layer, and 1 mass%-10 mass% are more preferable.

(Dye having an absorption maximum wavelength of 350 to 450 nm)
The photosensitive layer according to the present invention preferably contains a sensitizing dye having an absorption maximum in the wavelength range of 350 to 450 nm.

  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.

  Of these sensitizing dyes, a coumarin dye represented by the following general formula (A) is preferably used.

Wherein, R ³¹ to R ³⁶ represents a hydrogen atom, a substituent group. Examples of the substituent include an alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), A cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), an alkenyl group (eg, vinyl group, allyl group, etc.), an alkynyl group (eg, ethynyl group, propargyl group, etc.), an aryl group (eg, phenyl group, naphthyl group). Etc.), heteroaryl group (for example, furyl group, thienyl group, pyridyl group, pyridazyl group, pyrimidyl group, pyrazyl group, triazyl group, imidazolyl group, pyrazolyl group, thiazolyl group, benzoimidazolyl group, benzoxazolyl group, quinazolyl group , Phthalazyl groups, etc.), heterocyclic groups (eg , Pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy Group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, naphthyloxy group, etc.), alkylthio group (eg, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group) Group, dodecylthio group etc.), cycloalkylthio group (eg cyclopentylthio group, cyclohexylthio group etc.), arylthio group (eg phenylthio group, naphthylthio group etc.), alkoxycarbonyl group (eg methyl Xycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, Aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2 -Pyridylaminosulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexyl group) A silcarbonyl group, an octylcarbonyl group, a 2-ethylhexylcarbonyl group, a dodecylcarbonyl group, a phenylcarbonyl group, a naphthylcarbonyl group, a pyridylcarbonyl group, etc.), an acyloxy group (for example, an acetyloxy group, an ethylcarbonyloxy group, a butylcarbonyloxy group) Octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonyl) Amino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylca Bonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group) , Dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecyl group) Ureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethyls) Finyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group) , Butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group (phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group etc.), amino group (for example, amino group, ethyl group) Amino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridyla Mino group, etc.), halogen atoms (for example, fluorine atom, chlorine atom, bromine atom etc.), cyano group, nitro group, hydroxy group and the like. These substituents may be further substituted with the above substituents. In addition, a plurality of these substituents may be bonded to each other to form a ring.

Among these, particularly preferred is a coumarin having an amino group, an alkylamino group, a dialkylamino group, an arylamino group, a diarylamino group or an alkylarylamino group as R ³⁵ . In this case, an alkyl group substituted with an amino group that forms a ring with the substituents of R ³⁴ and R ³⁶ can also be preferably used.

Further, either or both of R ³¹ and R ³² are alkyl groups (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group). Group, tetradecyl group, pentadecyl group etc.), cycloalkyl group (eg cyclopentyl group, cyclohexyl group etc.), alkenyl group (eg vinyl group, allyl group etc.), aryl group (eg phenyl group, naphthyl group etc.), Heteroaryl group (for example, furyl group, thienyl group, pyridyl group, pyridazyl group, pyrimidyl group, pyrazyl group, triazyl group, imidazolyl group, pyrazolyl group, thiazolyl group, benzoimidazolyl group, benzoxazolyl group, quinazolyl group, phthalazyl group Etc.), heterocyclic groups (eg, pyrrolidyl group, imida Zolidyl group, morpholyl group, oxazolidyl group etc.), alkoxycarbonyl group (eg methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group etc.), aryloxycarbonyl group (eg , Phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group) , Phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyl) Xy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexyl) Aminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group) Group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group Group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (eg, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), aryl Sulfonyl group (phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), halogen atom (for example, fluorine atom, chlorine atom, bromine atom, etc.), cyano group, nitro group, halogenated alkyl group (trifluoromethyl group) , Tribromomethyl group, trichloromethyl group, etc.).

  Preferable specific examples include, but are not limited to, the following compounds.

  In addition to the above specific examples, 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, JP-A-2002-363206 No. 1 to 21 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 No. 1 56 coumarin derivatives and the like can also be preferably used.

  Hereinafter, the various additives that can be added to the photosensitive layer according to the present invention, the support, the protective layer, the layering of the photosensitive layer, and the processing method of the photosensitive lithographic printing plate material will be sequentially described.

(Various additives)
In addition to the components described above, the photosensitive layer of the present invention is polymerized in order to prevent unnecessary polymerization of the polymerizable ethylenic double bond monomer during the 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-5) -Methylbenzyl) -4-methylphenyl acrylate and the like.

  The addition amount of the polymerization inhibitor is preferably about 0.01% to about 5% with respect to the mass of the photosensitive layer. If necessary, higher fatty acid derivatives such as behenic acid and behenic acid amide may be added to prevent polymerization inhibition due to oxygen, or it may be unevenly distributed on the surface of the photosensitive layer during the drying process after coating. Good. The amount of the higher fatty acid derivative added is preferably about 0.5% to about 10% of the total composition.

  Moreover, a coloring agent can also be used and a conventionally well-known thing can be used conveniently as a coloring agent including a commercially available thing. Examples include 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 the pigment include black pigment, yellow pigment, red pigment, brown pigment, purple pigment, blue pigment, green pigment, fluorescent pigment, and metal powder pigment. 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.

  In order to form the photosensitive layer according to the present invention, it is preferable to prepare a coating solution for the photosensitive layer, and apply and dry it on a support. Examples of the solvent for the coating solution used in this case include alcohol: polyhydric alcohol derivatives such as sec-butanol, isobutanol, n-hexanol, benzyl alcohol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1, 5-pentanediol, ethers: propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, ketones, aldehydes: diacetone alcohol, cyclohexanone, methylcyclohexanone, esters: ethyl lactate, lactic acid Preferred are butyl, diethyl oxalate, methyl benzoate and the like.

(Protective layer: oxygen barrier layer)
If necessary, a protective layer can be provided on the upper side of the photosensitive layer according to the present invention.

  This protective layer (oxygen barrier layer) preferably has high solubility in a developer described later, and specific examples include polyvinyl alcohol and polyvinyl pyrrolidone. Polyvinyl alcohol has an effect of suppressing permeation of oxygen, and polyvinyl pyrrolidone has an effect of ensuring adhesion with an 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 a protective layer is provided, the peel force between the photosensitive layer and the protective layer is preferably 35 mN / mm or more, more preferably 50 mN / mm or more, and even more preferably 75 mN / mm or more. Preferred examples of the protective layer composition include those described in Japanese Patent Application No. 8-161645.

  The peeling force is a force when an adhesive tape of a predetermined width having a sufficiently large adhesive force is applied on the protective layer and peeled off with the protective 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 protective layer can further contain a surfactant, a matting agent and the like as required. The protective layer composition is dissolved in a suitable solvent, applied onto the photosensitive layer and dried to form a protective layer. The main component of the coating solvent is particularly preferably water or alcohols such as methanol, ethanol, i-propanol.

  When providing a protective layer, the thickness is preferably from 0.1 to 5.0 μm, particularly preferably from 0.5 to 3.0 μm.

(Support)
The support according to the present invention can carry a photosensitive layer and has a hydrophilic surface.

  As the support having a hydrophilic surface, a support having a hydrophilic surface layer and a substrate provided with a hydrophilic layer containing a hydrophilic substance can be used.

  Examples of the support according to the present invention include a metal plate, a plastic film, paper treated with polyolefin and the like, and a composite substrate obtained by appropriately bonding the above materials.

  The thickness of the support is not particularly limited as long as it can be attached to a printing press, but a thickness of 50 to 500 μm is generally easy to handle.

  As the support according to the present invention, a metal plate obtained by hydrophilizing the substrate surface is preferably used.

  Examples of the metal plate include iron, stainless steel, and aluminum. In the present invention, the effect of the present invention is particularly great when aluminum or an aluminum alloy (hereinafter referred to as an aluminum plate) is used. As the aluminum plate, a plate subjected to any of the known roughening treatment, anodizing treatment, and surface hydrophilization treatment (so-called aluminum grained plate) is preferably 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. .

  Prior to roughening (graining treatment), the support is preferably subjected to 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.

  As a roughening method, roughening is performed by electrolysis, but before that, roughening can be performed by, for example, a mechanical method.

The mechanical roughening method used is not particularly limited, but a brush polishing method and a honing polishing method are preferable. The roughening by the brush polishing method is, for example, by rotating a rotating brush using a bristle having a diameter of 0.2 to 0.8 mm, and for example, volcanic ash particles having a particle size of 10 to 100 μm on water. While supplying the uniformly dispersed slurry, the brush can be pressed. The roughening by honing polishing is performed by, for example, uniformly dispersing volcanic ash particles having a particle size of 10 to 100 μm in water, injecting pressure from a nozzle, and causing the surface to collide obliquely with the support surface. Can do. Further, for example, abrasive particles having a particle size of 10 to 100 μm are applied to the support surface so as to be present at a density of 2.5 × 10 ³ to 10 × 10 ³ particles / cm ² at intervals of 100 to 200 μm. Roughening can also be performed by laminating the sheets and applying a pressure to transfer the rough surface pattern of the sheet.

After the surface is roughened by the mechanical surface roughening method, it is preferable to immerse in an aqueous solution of acid or alkali in order to remove the abrasive that has digged into the surface of the support, formed aluminum scraps, and the like. 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 aqueous alkali solution such as sodium hydroxide. The dissolution amount of aluminum in the support surface, 0.5 to 5 g / m ² is preferred. After the immersion treatment with an alkaline aqueous solution, it is preferable to carry out a neutralization treatment by immersion in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid or a mixed acid thereof.

As a roughening method, roughening by electrolysis is performed. In this method, the surface is electrochemically roughened in an acidic electrolytic solution, and the acidic electrolytic solution has an effective value of 30 A in a hydrochloric acid or nitric acid solution having a concentration of 0.4% by mass to 2.8% by mass. / dm ² or more 100A / dm ² or less at a current density of 10 seconds to 120 seconds, performing electrolytic graining. The concentration of hydrochloric acid or nitric acid is more preferably 1% by mass or more and 2.3% by mass or less. Current density is more preferably 30A / dm ² or more 80A / dm ² or less, further preferably 40A / dm ² or more 75A / dm ² or less.

The temperature at which the electrolytic surface-roughening method is performed is not particularly limited, but is preferably in the range of 5 ° C. to 80 ° C., more preferably in the range of 10 ° C. to 60 ° C. The applied voltage is not particularly limited, but is preferably performed by applying a voltage in the range of 1 to 50 volts, and more preferably in the range of 10 to 30 volts. Quantity of electricity is not particularly limited, it is preferable to use a range of 5000 C / dm ^2, still preferably selected from the range of 100~2000c / dm ^2.

  If necessary, nitrate, chloride, amines, aldehydes, phosphoric acid, chromic acid, boric acid, acetic acid, oxalic acid, and the like can be added to the electrolytic solution.

After the surface is roughened by the electrolytic surface roughening method, it is preferably immersed in an acid or alkaline 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.

  Following the electrolytic surface 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. For the anodizing treatment, a method of electrolyzing an aqueous solution containing sulfuric acid and / or phosphoric acid at a concentration of 10 to 50% as an electrolytic solution at a current density of 1 to 10 A / dm ² is preferably used. A method of electrolysis at a high current density in sulfuric acid described in Japanese Patent No. 1,412,768, a method of electrolysis using phosphoric acid described in Japanese Patent No. 3,511,661, chromic acid, Examples thereof include a method using a solution containing one or more oxalic acid, malonic acid and the like. The formed anodic oxidation coating amount is suitably 1 to 50 mg / dm ² , preferably 10 to 40 mg / dm ² . The anodized coating amount is obtained by, for example, immersing an aluminum plate in a chromic phosphate solution (85% phosphoric acid solution: 35 ml, prepared by dissolving 20 g of chromium (IV) oxide in 1 L of water) to dissolve the oxide film, It is obtained from mass change measurement before and after dissolution of the coating on the plate.

  In the present invention, the support is preferably treated with a sodium silicate solution having a temperature of 20 ° C. or more and 50 ° C. or less after the anodizing treatment. The temperature is preferably 20 ° C. or higher and 50 ° C. or lower, and more preferably 20 ° C. or higher and 45 ° C. or lower. If it is less than 20 ° C., it may become dirty and recovery may be worsened. Further, if it is higher than 50 ° C., the printing durability may be deteriorated. The concentration of sodium silicate is not particularly limited, but is preferably 0.01% or more and 35% or less, and more preferably 0.1% or more and 5% or less.

  In the present invention, the support is preferably treated with a polyvinylphosphonic acid solution having a temperature of 20 ° C. or more and 70 ° C. or less after the anodizing treatment. The temperature is preferably 20 ° C. or higher and 70 ° C. or lower, and more preferably 30 ° C. or higher and 65 ° C. or lower. If it is less than 20 ° C., it may become dirty and recovery may be worsened. On the other hand, if it is higher than 70 ° C., the printing durability may be deteriorated. The concentration of the polyvinylphosphonic acid solution is not particularly limited, but is preferably 0.01% or more and 35% or less, and more preferably 0.1% or more and 5% or less.

(Image exposure)
As a light source used for image exposure according to the present invention, it is preferable to use laser light having an emission wavelength of 350 to 450 nm, particularly preferably 400 nm to 450 nm.

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

  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.

In the present invention, image recording 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 10-300 mJ / cm < ² >. For this energy measurement, for example, a laser power meter PDGDO-3W manufactured by OphirOptics can be used.

(Developer)
The printing plate material that has undergone image exposure is developed with a developer to remove unexposed portions of the photosensitive layer. As the developer to be used, a conventionally known alkaline aqueous solution can be used. For example, sodium silicate, potassium, ammonium; dibasic sodium phosphate, potassium, ammonium; sodium bicarbonate, potassium, ammonium; sodium carbonate, potassium, ammonium; sodium bicarbonate, potassium, ammonium An alkali developer using an inorganic alkaline agent such as sodium borate, potassium, ammonium; sodium hydroxide, potassium, ammonium and lithium;

  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.

  These alkali agents are used alone or in combination of two or more. In addition, an organic solvent such as an anionic surfactant, an amphoteric surfactant or alcohol can be added to the developer as necessary.

(Automatic processor)
It is advantageous to use an automatic developing machine for the development processing according to the present invention. The automatic developing machine is preferably provided with a mechanism for automatically replenishing the required amount of the developing replenisher to the developing bath, and preferably provided with a mechanism for discharging the 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 plate passing is provided, preferably a mechanism for estimating the processing area of the plate based on detection of plate passing. Preferably, a mechanism for controlling the replenishment amount and / or replenishment timing of the replenisher and / or water to be replenished based on the detection of the printing plate and / or the estimation of the processing area is provided. Is provided with a mechanism for controlling the temperature of the developer, preferably a mechanism for detecting the pH and / or conductivity of the developer, preferably based on the pH and / or conductivity of the developer. Trying to replenish The amount of replenisher supplied and / or water and / or mechanism for controlling the replenishment timing is given that. The developer concentrate preferably has a function of once diluting and stirring with water. When there is a rinsing step after the development step, the rinsing water after use can be used as dilution water for the concentrate of the development concentrate.

(Step of exposing after development)
The processing method of this invention has the process of exposing with the actinic light which has a wavelength less than the wavelength of the exposure light used for image exposure after image development processing.

  In the present invention, the photosensitive layer uses a photosensitive lithographic printing plate material containing a polyhalogen compound and titanium oxide, and is exposed to an actinic ray having a wavelength less than the wavelength of the exposure light used for image exposure after development processing. Thus, a printing plate having a small dot gain, excellent anti-unexposed-part stain resistance, and excellent printing durability can be obtained.

  In the present invention, the wavelength of exposure light used for image exposure after development is preferably 400 nm or less, and particularly preferably 250 nm to 390 nm.

  As a light source used for the exposure after the development, an ultraviolet light source such as a mercury lamp or a halogen lamp is preferably used. As the exposure conditions, the above light source having a light source of 1 kW or more, preferably 5 kW or more is used, the distance between the light source and the printing plate material is 0.01 m to 1 m, and the exposure time is 5 seconds or more, preferably 10 seconds. The above is preferable.

  In the present invention, a printing plate having excellent printing durability and low dot gain can be obtained without performing heat treatment at a temperature of 100 ° C. or higher for improving the printing durability that has been conventionally performed. .

(Post-processing after development)
In the present invention, the following post-treatment is preferably performed between the development treatment and the exposure step after the development, or after the exposure.

  The developed printing plate material is subjected to post-treatment with a washing water, a rinse solution containing a surfactant and the like, a finisher mainly composed of gum arabic or starch derivatives, or a protective gum solution. These treatments can be used in various combinations. For example, the treatment with a rinsing solution containing development-> washing-> surfactant or the development-> washing-> finisher solution is preferable because of less fatigue of the rinse solution and the finisher solution. Furthermore, a countercurrent multistage process using a rinse liquid or a finisher liquid is also a preferred embodiment.

  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. A method is also known in which a fixed amount of a small amount of washing water is supplied to the plate surface after development, and the waste liquid 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 treatment method in which treatment is performed with a substantially unused post-treatment liquid is also applicable. The lithographic printing plate obtained by such processing is loaded on an offset printing machine and used for printing a large number of sheets.

  It is preferable to add an acid or a buffer to the protective gum solution to remove the alkali component of the developer. In addition, a hydrophilic polymer compound, a chelating agent, a lubricant, a preservative, a solubilizing agent, and the like may be added. it can. When the gum solution contains a hydrophilic polymer compound, a function as a protective agent for preventing scratches and stains on the developed plate is also added.

(Washing water before development)
Before the development processing according to the present invention, it may have a step of processing with pre-development washing water as necessary. The pre-development washing water is usually water, but the following additives can be added as necessary.

  As the chelating agent, a compound that forms a chelate compound by coordination with a metal ion is used. Ethylenediaminetetraacetic acid, its potassium salt, sodium salt, ethylenediamine disuccinic acid, its potassium salt, sodium salt, triethylenetetramine hexaacetic acid, its potassium salt, sodium salt, diethylenetriaminepentaacetic acid, its potassium salt, sodium salt, hydroxyethylethylenediamine Triacetic acid, its potassium salt, sodium salt, nitrilotriacetic acid, its potassium salt, sodium salt, 1-hydroxyethane-1,1-diphosphonic acid, its potassium salt, sodium salt, aminotri (methylenephosphonic acid), its potassium salt Sodium salt, phosphonoalkanetricarboxylic acid, ethylenediamine disuccinic acid, potassium salt thereof, sodium salt and the like. Those chelating agents having an organic amine salt instead of the potassium salt and sodium salt are also effective. The addition amount of the chelating agent is suitably in the range of 0 to 3.0% by mass.

  As the surfactant, any of anionic, nonionic, cationic and amphoteric surfactants can be used, and anionic or nonionic surfactants are preferred. The preferred surfactant type varies depending on the composition of the overcoat layer and the photosensitive layer, and generally serves as a dissolution accelerator for the material of the overcoat layer and preferably has a low solubility for the components of the photosensitive layer.

  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.

Example 1
<< Polymer binder: 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 for 6 hours in an oil bath at 0 ° C. 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]
Using a JISA1050 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 . Thereafter, washing with water was performed by spraying.

  (B) A desmut treatment was performed by spraying with a 1% by mass aqueous solution of nitric acid having 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.

  As the electrolytic solution, one containing 0.5 mass% aluminum ions and 0.007 mass% acetic acid and having a temperature of 21 ° C. was used.

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 an effective value of 50 A / dm ² 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 phosphoric acid concentration 20 mass% aqueous solution (containing 0.5 mass% of aluminum ions) at a temperature of 60 ° C., followed by washing with water by spraying.

(E) An anodizing apparatus of 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 / liter (containing 0.5 mass% of aluminum ions) at a temperature of 38 ° C. Thereafter, washing with water was performed by spraying. At this time, in the anodizing device, the current from the power source flows to the first power supply electrode provided in the first power supply unit, flows to the plate-like aluminum via the electrolytic solution, An oxide film is formed on the surface, 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 portion, similarly flows to the plate-like aluminum via the electrolytic solution, and an oxide film is formed on the surface of the plate-like aluminum by the second electrolysis portion. Although 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, the feeding current density on the oxide film surface in the second feeding unit is about It was 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 wt% polyvinylphosphonic acid solution for 30 seconds, and subjected to a hydrophilic treatment. The temperature was 75 ° C. Thereafter, it was washed with spray water and dried with an infrared heater. At this time, the center line average roughness (Ra) of the surface was 0.55 μm.

(Preparation of photosensitive lithographic printing plate material)
On the above support, a photopolymerizable photosensitive layer coating solution having the following composition was applied with a wire bar so that it would be 1.5 g / m ² when dried, and dried at 95 ° C. for 1.5 minutes. Got. Further, on the photopolymerization photosensitive layer coating sample, an oxygen barrier layer coating solution having the following composition was coated with a wire bar so as to be 1.8 g / m ² at the time of drying, and dried at 75 ° C. for 1.5 minutes. A photosensitive lithographic printing plate sample having an oxygen barrier layer on the layer was prepared.

(Photopolymerizable photosensitive layer coating solution)
Ethylene double bond-containing monomer (1-17 below) 27.0 parts Ethylene double bond-containing monomer (NK ester 4G: Shin-Nakamura Chemical Co., Ltd.)
14.0 parts Spectral sensitizing dye (dye-1 below) 3 parts 2,2′-bis (o-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole 4.0 parts polyhalogen compound ( Compounds described in Table-1) 4 parts Titanium oxide particles (compounds described in Table-1) 2 parts Acrylic copolymer 1 (above) 45.0 parts Phthalocyanine pigment (MHI454: manufactured by Mikuni Dye Co.) 6.0 parts 2 -T-Butyl-6- (3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate (Sumilyzer GS: manufactured by Sumitomo 3M) 0.5 parts Fluorine-based surfactant (FC- 4430; manufactured by Sumitomo 3M Co., Ltd.) 0.5 parts Siloxane surfactant (BYK337; manufactured by BYK Chemie) 0.9 parts Methyl ethyl ketone 80 parts Propylene glycol methyl ether 820 parts

(Oxygen barrier coating liquid)
Polyvinyl alcohol (GL-05: manufactured by Nippon Synthetic Chemical Co., Ltd.) 79 parts Polyvinylpyrrolidone (PVP K-30: manufactured by ASP Japan) 10 parts Polyethyleneimine (Lupazole WF: manufactured by BASF) 5 parts Cationic modified polyvinyl alcohol (Kuraray) C polymer: Kuraray Co., Ltd.) 5 parts Surfactant (Surfinol 465: Nissin Chemical Industry Co., Ltd.) 0.5 part Water 900 parts <Developer composition>
A Potassium silicate 8.0 parts New Coal B-13SN (manufactured by Nippon Emulsifier Co., Ltd.) 2.0 parts Pronon # 204 (Nippon Yushi Co., Ltd.) 1.0 parts Caustic potash pH = 12.9 (Evaluation)
Using a plate setter (manufactured by ECRM) equipped with a light source of 405 nm under the condition that the exposure energy on the printing plate is 50 μJ / cm ² , exposure is performed at 2400 dpi (dpi represents the number of dots per 2.54 cm). Went. After exposure, the photosensitive lithographic printing plate material was processed under the conditions shown in Table-1. The heating shown in Table-1 is a treatment performed for 30 seconds in a thermostatic bath so that the plate surface temperature becomes the temperature described in the table before development. In addition, a pre-rinsing part for removing the oxygen blocking layer before development, a developing part filled with a developing solution, a washing part for removing the developing solution adhering to the plate surface, a gum solution for protecting the image area (GW-3: Mitsubishi Chemical Corporation) Gum solution was processed with a CTP automatic developing machine (Raptor 85 Polymer: manufactured by Glunz & Jensen) equipped with a processing section and dried.

  The UV irradiation shown in Table-1 is for pre-water washing part that removes the oxygen blocking layer after exposure, before development, developing part filled with developer, water washing part that removes developer adhering to the plate surface, and for image area protection. Gum solution (GW-3: manufactured by Mitsubishi Chemical Co., Ltd., 2 times diluted) is processed and dried so that the plate surface temperature is 50 ° C., and then at a distance of 0.3 m using UV exposure apparatus L1282 (8 kW) manufactured by OLEC. For 20 seconds.

[Dot Gain]
Table 1 shows the values obtained by measuring the percentage of the halftone dot corresponding to 60% output under the condition of 2400 dpi / 175 line without correction with the unexposed area as zero, and subtracting 60% from the measured value. The measuring device uses a CCDot manufactured by SDG, and the closer to zero, the smaller the dot gain, which is preferable.

[Press life]
The prepared lithographic printing plate was coated with a printing press (DAIYA1F-1 manufactured by Mitsubishi Heavy Industries, Ltd.), printing ink (Toyo King High Echo M Red manufactured by Toyo Ink Co., Ltd.) and dampening water (Tokyo Ink Co., Ltd.). ) Manufactured H liquid SG-51 density 1.5%), and after printing 500 sheets continuously, wipe the plate surface with a cleaner to reduce the number of prints where the highlight part is thin and the shadow part is entangled. It was used as an index of printing force. The printing durability once refers to the operation of wiping with a cleaner after continuous printing of 500 sheets. The more it is, the better. The cleaner used was an Ultra Plate Cleaner (Distributor: Dainichi Seika).

[Prevention of unexposed area contamination]
The prepared lithographic printing plate was coated with a printing press (DAIYA1F-1 manufactured by Mitsubishi Heavy Industries, Ltd.), printing ink (Toyo King High Echo M Red manufactured by Toyo Ink Co., Ltd.) and dampening water (Tokyo Ink Co., Ltd.). ) H liquid SG-51 concentration 1.5%).

  After printing 10,000 sheets, spot-like ink stains were observed on the unexposed area (non-image area) with a 50 × magnifier. The evaluation rank is 5 and there is no dirt at all, but 4 seems to be observed well, but there is no problem in practical use, 3 is found when you look into it with a magnifying glass, but there is no problem in practical use. No. 1 is apparently a problem in practical use, and No. 1 is obviously impractical due to frequent ink stains.

  The results are shown in Table 1. From Table 1, it can be seen that the processing method of the present invention is excellent in printing durability, has little dot gain, and has good linearity and anti-unexposed-part stain resistance.

Trichlorotriazine 1: 2-phenyl-4,6-bis (trichloromethyl) -s-triazine TTO-51 (A) (particle size 0.01 to 0.03 μm), TTO-55 (C) (particle size 0. 03-0.05 μm): Titanium oxide manufactured by Ishihara Sangyo Co., Ltd.

Claims (4)

An image of a photosensitive lithographic printing plate material having a photosensitive layer containing (A) an addition-polymerizable ethylenic double bond-containing compound, (B) a photopolymerization initiator, and (C) a polymer binder on a support. A processing method of exposing and developing, wherein the photosensitive layer further initiates polymerization with (D) titanium oxide particles and (E) an actinic ray having a wavelength less than the wavelength of the exposure light used for the image exposure A photosensitive lithographic printing plate material comprising a polyhalogen compound capable of being exposed to an actinic ray having a wavelength less than that of the exposure light used for image exposure after the development treatment Processing method. 2. The method for processing a photosensitive lithographic printing plate material according to claim 1, wherein the wavelength of exposure light used for the image exposure is 400 nm or more. 3. The method for processing a photosensitive lithographic printing plate material according to claim 1, wherein the wavelength of the actinic ray having a wavelength less than that of the exposure light used for the image exposure is less than 400 nm. A photosensitive lithographic printing plate material, which is used in the method for processing a photosensitive lithographic printing plate material according to any one of claims 1 to 3.