JP2009276599A - Lithographic printing plate making method and processing method for photosensitive lithographic printing plate material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: a lithographic printing plate making method by which, though a photopolymerizable photosensitive lithographic printing plate material of an image exposure type with short-wavelength light having a wavelength of 350-450 nm and low energy is used, high sensitivity, excellent staining resistance of a non-image area and excellent sludge generation resistance are ensured even upon development at low pH; a processing method for a photosensitive lithographic printing plate material; and a lithographic printing plate making method (further, a lithographic printing method) by which high sensitivity, excellent printing durability and white-light safety are ensured even upon on-press development and printing. <P>SOLUTION: The lithographic printing plate making method includes a step of exposing a photosensitive lithographic printing plate material to image information with a laser light source at a temperature of the plate surface in a range of 50-130°C, wherein the photosensitive lithographic printing plate material has on a support a photosensitive layer containing a spectral sensitizing agent having an absorption maximum at 350-450 nm, a polymerization initiator, a coinitiator, a polymerizable monomer and a polymer binder as an outermost layer. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image forming method using a photosensitive lithographic printing plate material used in a so-called computer-to-plate (hereinafter referred to as “CTP”) system, and a photosensitive lithographic plate. In particular, the present invention relates to a processing method of a printing plate material and a lithographic printing method. In particular, a lithographic printing plate preparation method and a photosensitive method using a specific photosensitive lithographic printing plate material suitable for specific exposure with a laser beam having a wavelength of 350 to 450 nm. The present invention relates to a method for processing a photolithographic printing plate material.

  In recent years, digitization technology that electronically processes, stores, and outputs image information using a computer has become widespread, and in printing plate preparation technology for offset printing, directivity is determined according to digitized image information. A so-called CTP system that scans a high laser beam and directly records it on a photosensitive lithographic printing plate material has been developed and put into 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.)

  Light sources such as Ar laser (488 nm) and YD-YAG (532 nm) are known as light sources used for the polymerization type photosensitive layer, but the output is not sufficiently high in plate making using these light sources. Therefore, it is insufficient to increase the productivity of the plate making process, and the workability is insufficient from the viewpoint of the use of the safelight.

  On the other hand, in recent years, lasers capable of continuous transmission within the range of high-power and small-sized shortwave light (wavelength: 350 to 450 nm) have become readily available. In order to improve the above-described productivity and safelight properties, photosensitive lithographic printing plate materials suitable for these short-wave lasers have been developed. For example, a photosensitive lithographic printing plate material containing biimidazole in the photosensitive layer is known. Further, as a photopolymerizable composition having high sensitivity and low sublimation, for example, an aryl group having a substituent such as an alkyl group. A photopolymerizable composition containing a hexaarylbiimidazole compound containing benzene is known (see, for example, Patent Documents 3 and 4).

  However, the above-mentioned short-wave light (wavelength 350 to 450 nm) image-exposure type photosensitive lithographic printing plate material suitable for a short-wave laser is usually subjected to heat treatment as necessary after image exposure. After that, washing with water for removing the oxygen blocking layer, developing treatment for dissolving and removing unexposed portions (non-image portions), washing with water, finisher gum treatment for hydrophilizing the non-image portions, It has gained. In preparing a lithographic printing plate from this photosensitive lithographic printing plate material, in order to completely remove the unexposed photosensitive layer of the photosensitive layer, that is, to perform development, usually, a pH 12. It was common to use 5 or more.

  However, in recent years, treatment with a developer having a lower pH has been desired from the viewpoint of workability, safety, environmental suitability, and the like. However, such a relatively low pH developer basically has poor dissolving power of the photosensitive layer, and therefore has problems such as insufficient development and contamination of non-image areas.

  For the photopolymerization type photosensitive lithographic printing plate material described above, since a high-power laser is used for an infrared plate material of an infrared image exposure type, a plate material without a protective layer has been put into practical use. However, the short-wave light, short-wave light (wavelength 350 to 450 nm), which is a violet plate material, photo-exposure type photolithographic lithographic printing plate material is still inadequate, so the laser output is still insufficient. Therefore, it is necessary to increase the sensitivity by preventing radical generation from being suppressed by oxygen and to form an image. Therefore, it is not possible to have no protective layer, and a plate material without a protective layer is practical. It was not converted.

  However, if there is a protective layer, in the process of “development with a low pH developer, lithographic printing plate, printing”, so-called chemical-free development (gum development), development is delayed and sludge increases. In addition, there is a problem in that the background stain on the non-image area increases during printing.

In addition, in the case of on-press development printing in which development printing is performed on the press when there is a protective layer, development failure and fogging occur, and practical application is impossible.
JP-A-1-105238 JP-A-2-127404 JP 2001-194882 A JP 2004-137152 A

  As a result of intensive studies, the present inventor has conventionally found that a photosensitive layer having no protective layer and having a photosensitive layer as the outermost layer has a low sensitivity because oxygen hardly permeates and polymerizes. Even if the lithographic printing plate material is heated at the time of exposure, a large amount of radicals are generated even when exposed to violet laser (350 to 450 nm), polymerization is possible and sensitivity can be increased, and the lithographic printing plate can be obtained from the difference in radical generation rate and extinction rate. It became possible to form.

  That is, even in the case of a photopolymerization type photosensitive lithographic printing plate material of a short wave light (wavelength 350 to 450 nm) image exposure type, exposure of 350 to 450 nm light can be performed by increasing the temperature of the photosensitive lithographic printing plate material at the time of exposure. However, since the high sensitivity can be achieved without a protective layer, the protective layer is high and the sensitivity is high. The printing plate material can be obtained quickly and excellently, and since it does not have a protective layer and is highly sensitive, it is excellent in scumming resistance, printing durability, and white light safety even for on-press development printing. The present inventors have found that on-press development printing can be performed quickly, and have reached the present invention.

The present invention has been made in view of the above problems, and the object of the present invention is to
Image formation with specific image exposure using specific photosensitive lithographic printing plate material despite the use of photopolymerization type photosensitive lithographic printing plate material of short-wavelength light wavelength 350-450 nm and low energy By increasing the sensitivity by the method,
An object of the present invention is to provide a method for preparing a lithographic printing plate and a method for processing a photosensitive lithographic printing plate material, which are highly sensitive even in development processing at a low pH, and have excellent resistance to scumming and sludge generation in non-image areas.

  Another object of the present invention is to provide a lithographic printing plate preparation method (further, a lithographic printing method) that has high sensitivity in on-press development printing and is excellent in printing durability and white light safety.

  The above object of the present invention can be achieved by the following constitution.

  1. A photosensitive lithographic printing plate having a photosensitive layer containing a spectral sensitizer having a maximum absorption at 350 to 450 nm, a polymerization initiator, a co-initiator, a polymerizable monomer, and a polymer binder as an outermost layer on a support. A method for preparing a lithographic printing plate, comprising the step of exposing image information with a laser light source at a temperature of 50 ° C to 130 ° C of the plate surface of the photosensitive lithographic printing plate material at the time of exposure.

  2. A photosensitive lithographic printing plate having a photosensitive layer containing a spectral sensitizer having a maximum absorption at 350 to 450 nm, a polymerization initiator, a co-initiator, a polymerizable monomer, and a polymer binder as an outermost layer on a support. The material is exposed to image information with a laser light source at a temperature of the plate surface of the photosensitive lithographic printing plate material at the time of exposure of 50 ° C. to 130 ° C., and contains a water-soluble resin and a surfactant and has a pH at 25 ° C. A method for treating a photosensitive lithographic printing plate material, wherein an unexposed portion is removed with an aqueous solution having an A of 3.0 to 9.0 to obtain a lithographic printing plate.

  3. A photosensitive lithographic printing plate having a photosensitive layer containing a spectral sensitizer having a maximum absorption at 350 to 450 nm, a polymerization initiator, a co-initiator, a polymerizable monomer, and a polymer binder as an outermost layer on a support. The material is exposed to image information with a laser light source in the temperature range of the plate surface of the photosensitive lithographic printing plate material at the time of exposure to 50 ° C to 130 ° C, and printing ink and fountain solution are supplied to remove non-image areas. A method for preparing a lithographic printing plate, comprising:

  According to the present invention, a specific photosensitive lithographic printing plate material is used in spite of the use of a photopolymerization type photosensitive lithographic printing plate material of a short wave light wavelength of 350 to 450 nm and low energy. By increasing the sensitivity by an image forming method that performs image exposure, a high sensitivity even in development processing at low pH, excellent resistance to scumming and sludge generation in non-image areas, a lithographic printing plate preparation method, and photosensitivity A method for processing a sex lithographic printing plate material can be provided.

  In addition, it is possible to provide a lithographic printing plate preparation method (further, a lithographic printing method) with high sensitivity and excellent printing durability and white light safety even in on-press development printing.

  Hereinafter, although the best mode for carrying out the present invention will be described, the present invention is not limited to these.

  Hereinafter, it explains in detail according to the component of the present invention.

<< Photosensitive planographic printing plate material >>
The photosensitive lithographic printing plate material according to the present invention contains, on a support, a spectral sensitizer having an absorption maximum at 350 to 450 nm, a polymerization initiator, a coinitiator, a polymerizable monomer, and a polymer binder. It has a photosensitive layer as an outermost layer.

<Photosensitive layer>
The photosensitive layer according to the present invention contains, on a support, a spectral sensitizer having an absorption maximum at 350 to 450 nm, a polymerization initiator, a coinitiator, a polymerizable monomer, and a polymer binder.

(Polymerization initiator)
The photosensitive layer according to the present invention contains a polymerization initiator.

  As the polymerization initiator according to the present invention, a wide range of compounds capable of initiating a polymerizable monomer polymerization reaction triggered by a reaction of generating radical species and the like by photothermal heat can be used.

  As the polymerization initiator according to the present invention, hexaarylbiimidazole is preferably used. Processes for the preparation of hexaarylbiimidazole (HABI, triaryl-imidazole dimer) compounds used in the present invention are described in DE 1,470,154 and their use in photopolymerizable compositions. Use is described in EP 24,629, EP 107,792, US 4,410,621, EP 215,453 and DE 3,211,312. 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.

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

  Examples of titanocene compounds include compounds described in JP-A-63-41483 and JP-A-2-291. More preferred specific examples include bis (cyclopentadienyl) -Ti-di-chloride, bis (Cyclopentadienyl) -Ti-bis-phenyl, bis (cyclopentadienyl) -Ti-bis-2,3,4,5,6-pentafluorophenyl, bis (cyclopentadienyl) -Ti-bis -2,3,5,6-tetrafluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,4,6-trifluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,6 -Difluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,4-difluorophenyl, bis (methylcyclopentadienyl) -Ti-bis- , 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 Japan), bis (cyclopentadienyl) -bis (2,6-difluoro-3- (py-1-yl) phenyl) titanium (IRUGACURE 784: Ciba Made in Japan), bis (cyclopentadienyl) -bis (2,4,6-trifluoro-3- (pyridin-1-yl) phenyl) titanium bis (cyclopentadienyl) -bis (2,4,4) 6-trifluoro-3- (2-5-dimethylpyridinyl) phenyl) titanium and the like.

  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 iron arene complex compound include compounds described in JP-A-59-219307. More preferred 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- Examples include xylene- (η-cyclopentadienyl) iron hexafluorophosphate, η-benzene- (η-cyclopentadienyl) iron tetrafluoroborate.

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

  Among these, a halogen compound represented by the following general formula (PIH2) is particularly preferably used.

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

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

  A compound in which a polyhalogen methyl group is substituted on the oxadiazole ring is also preferably used. Furthermore, the oxadiazole compounds described in JP-A Nos. 5-34904, 45875 and 8-240909 are also preferably used.

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

  In addition, any polymerization 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, as the polymerization initiator that can be used in combination, the following can be used.

  Benzoin derivatives such as benzoin methyl ether, benzoin-i-propyl ether, α, α-dimethoxy-α-phenylacetophenone; benzophenone, 2,4-dichlorobenzophenone, methyl o-benzoylbenzoate, 4,4′-bis (dimethyl) Benzophenone derivatives such as amino) benzophenone; thioxanthone derivatives such as 2-chlorothioxanthone and 2-i-propylthioxanthone; anthraquinone derivatives such as 2-chloroanthraquinone and 2-methylanthraquinone; N-methylacridone, N-butylacridone and the like In addition to α, α-diethoxyacetophenone, benzyl, fluorenone, xanthone 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 Organic halogen compounds described in JP-A-59-107344, etc.

  The content of the polymerization initiator according to the present invention (total amount of polymerization initiator) is preferably 0.1% by mass to 20% by mass and preferably 0.5% by mass to 15% with respect to the polymerizable ethylenically unsaturated bond-containing compound. Mass% is particularly preferred.

(Co-initiator)
The photosensitive layer according to the present invention contains a coinitiator.

  The coinitiator according to the present invention preferably contains a compound represented by the following general formula (1).

  Here, the “co-initiator” refers to a compound having a function of promoting a polymerization reaction that proceeds with the reaction of a polymerization initiator described later.

[Wherein, X represents an oxygen atom, —NR ₁ — or selenium, R ₁ represents an alkyl group which may have a substituent, or an aryl group which may have a substituent, and Y represents N═ It represents an atomic group that forms a 5-membered heterocycle with the C—X moiety, and Y may further have a substituent. ]
More specifically, the compound represented by the general formula (1) used as a coinitiator in the present invention is preferably a compound represented by the following general formulas (2) to (6).

[R ₁ represents an alkyl group that may have a substituent, or an aryl group that may have a substituent, and R ₂ represents a hydrogen atom, an alkyl group that may have a substituent, or a substituent. Represents an aryl group which may have ]

[R ₂ represents a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent. ]

[R ₁ represents an alkyl group which may have a substituent or an aryl group which may have a substituent. ]

[R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent. ]

[R ₁ represents an alkyl group which may have a substituent or an aryl group which may have a substituent. R _{4 to} R ₇ represent a hydrogen atom, a halogen atom, an alkoxyl group, a dialkylamino group, an alkyl group that may have a substituent, or an aryl group that may have a substituent. ]
In the general formulas (1) to (6), X represents an oxygen atom, —NR ₁ —, or selenium, Y represents an atomic group that forms a 5-membered heterocycle with the N═C—X moiety, and Y represents further You may have a substituent.

R ₁ to R ₃ represents an aryl group which may have a an optionally substituted alkyl group, or a substituent.

R _{4 to} R ₇ represent a hydrogen atom, a halogen atom, an alkoxyl group, a dialkylamino group, an alkyl group that may have a substituent, or an aryl group that may have a substituent.

  The alkyl group which may have the above substituent is not particularly limited, but is methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, tert-butyl group. N-pentyl group, n-hexyl group, cyclohexyl group, 2-ethylhexyl group, octyl group, nonyl group, decyl group and other linear, branched, and cyclic alkyl groups, and those having any substituents are examples. As mentioned. The substituents that can be substituted on these alkyl groups are not particularly limited, and examples thereof include alkyl groups, alkoxy groups, alkylamino groups, dialkylamino groups, halogens, aryl groups, and aralkyl groups.

  Preferable examples include methyl group, ethyl group, n-butyl group, t-butyl group, methoxymethyl group, methoxyethyl group, benzyl group, chloromethyl group and the like.

  Examples of the aryl group that may have the above-described substituent include a phenyl group, a naphthyl group, and those having an arbitrary substituent on them. The substituent that can be substituted on the aryl group is not particularly limited, and examples thereof include an alkyl group, an alkoxy group, an alkylamino group, a dialkylamino group, a halogen, an aryl group, and an aralkyl group. Preferable examples include phenyl group, tolyl group, methoxyphenyl group, chlorophenyl group, t-butylphenyl group, dialkylaminophenyl group and the like.

  Specific examples of the compounds represented by the general formulas (1) to (6) are given below, but are not limited thereto.

  The amount of the compounds represented by the general formulas (1) to (6) is preferably 0.01 to 20% by mass, more preferably 0.1 to 15% by mass, based on the total solid content of the photosensitive layer. %. More preferably, it is 1.0-10 mass%.

(Co-initiator: tribromoacetylamide compound)
The photosensitive lithographic printing plate material according to the present invention may contain a tribromoacetylamide compound as a coinitiator in the photosensitive layer.

  Specific examples of the tribromoacetylamide compound that can be used in the present invention will be given below, but the present invention is not limited to these.

  The amount of the tribromoacetylamide compound according to the present invention is preferably 0.01 to 20% by mass, more preferably 0.1 to 15% by mass, based on the total solid content of the photosensitive layer. More preferably, it is 0.3-10 mass%.

  In the present invention, various co-initiators conventionally known in the technical field according to the present invention, for example, co-initiators disclosed in JP-A-08-254821 and JP-A-2005-062482 are used in combination. You can also.

(Polymerizable monomer)
The photosensitive layer according to the present invention contains a polymerizable monomer.

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

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

  The polymerizable monomer according to the present invention is not limited, but preferred examples thereof include 2-ethylhexyl acrylate, 2-hydroxypropyl acrylate, glycerol acrylate, tetrahydrofurfuryl acrylate, phenoxyethyl acrylate, nonylphenoxyethyl acrylate, tetrahydrofurfuryl. Monofunctional acrylic acid esters such as oxyethyl acrylate, tetrahydrofurfuryloxyhexanolide acrylate, acrylate of ε-caprolactone adduct of 1,3-dioxane alcohol, 1,3-dioxolane acrylate, or methacrylates of these acrylates, Methacrylic acid, itaconic acid, crotonic acid, maleate esters such as ethylene instead of itaconate, crotonate, maleate Recall diacrylate, Triethylene glycol diacrylate, Pentaerythritol diacrylate, Hydroquinone diacrylate, Resorcin diacrylate, Hexanediol diacrylate, Neopentyl glycol diacrylate, Tripropylene glycol diacrylate, Diacrylate of hydroxypivalate 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 , 3-dioxane diacrylate, tricyclodecane dimethylol acrylate, ε-cation of tricyclodecane dimethylol acrylate Lactone adduct, bifunctional acrylic acid ester such as diacrylate of diglycidyl ether of 1,6-hexanediol, or methacrylic acid, itaconic acid, crotonic acid in which these acrylates are replaced with methacrylate, itaconate, crotonate, maleate, Maleic acid esters, such as trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, trimethylolethane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate , Ε-caprolactone adduct of dipentaerythritol hexaacrylate, pyroga Multifunctional acrylic acid ester acid such as methyltriacrylate, propionic acid / dipentaerythritol triacrylate, propionic acid / dipentaerythritol tetraacrylate, hydroxypivalylaldehyde-modified dimethylolpropane triacrylate, or these acrylates with methacrylate, itaconate, Mention may be made of methacrylic acid, itaconic acid, crotonic acid, maleic acid ester, etc. instead of crotonate and 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, it is preferable to use an addition-polymerizable ethylenic double bond-containing compound containing a tertiary amino group in the molecule, which is a tertiary amine monomer. 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 a hydroxyl group and addition-polymerizable ethylenic double bond in the molecule include 2-hydroxyethyl methacrylate (MH-1), 2-hydroxyethyl acrylate (MH-2), 4-hydroxybutyl. Examples include acrylate (MH-4), 2-hydroxypropylene-1,3-dimethacrylate (MH-7), 2-hydroxypropylene-1-methacrylate-3-acrylate (MH-8), and the like.

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

M-1: reaction product of triethanolamine (1 mol), hexane-1,6-diisocyanate (3 mol), 2-hydroxyethyl methacrylate (3 mol) M-2: triethanolamine (1 mol), isophorone Reaction product of diisocyanate (3 mol) and 2-hydroxyethyl acrylate (3 mol) M-3: Nn-butyldiethanolamine (1 mol), 1,3-bis (1-isocyanato-1-methylethyl) Reaction product of benzene (2 mol) and 2-hydroxypropylene-1-methacrylate-3-acrylate (2 mol) M-4: Nn-butyldiethanolamine (1 mol), 1,3-di (isocyanatomethyl) ) Reaction of benzene (2 mol), 2-hydroxypropylene-1-methacrylate-3-acrylate (2 mol) 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.

  In the present invention, among the polymerizable monomers, it is particularly preferable to use a polymerizable compound having a hydroxyl group in the molecule in order to solve the above-mentioned problem according to the present invention.

  As the polymerizable compound having a hydroxyl group in the molecule that can be used in the present invention, a compound represented by the following general formula (PMOH) is preferable.

[Wherein, R ¹ represents a hydrogen atom or a methyl group, and X ¹ represents —CH ₂ —CR ² R ³ —CH ₂ —, — (CH ₂ —CH (OR ⁴ ) —CH ₂ —O) _m — _{^{CH 2 -CH (oR 5) CH}} 2 -, - (CH (R 6) CH 2 O) n -CH (R 6) CH 2 -, - CO-X 2 -CO- or -X ² - represents a. R ² and R ³ each independently represents a hydrogen atom, an alkyl group, or a substituted alkyl group. R ⁴ , R ⁵ and R ⁶ each independently represents a hydrogen atom or an alkyl group. X ² represents an arylene group, an alkylene group, or a cycloalkylene group. m and n represent the integer of 1-20. ]
Preferable alkyl groups of R ^{2 to} R ⁶ in the general formula (PMOH) include, for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group and the like. Of these, an alkyl group having 1 to 10 carbon atoms is preferable. Particularly preferably, an alkyl group having 1 to 5 is mentioned, and R ² and R ³ are particularly preferably an alkyl group having 1 to 4 carbon atoms, and particularly about R ^{4 to} R ⁶ , a methyl group is particularly preferable.

  Substituents of substituted alkyl include aryl groups (eg, phenyl group, naphthyl group, etc.), alkoxyl groups (eg, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, etc.), alkoxycarbonyl groups ( For example, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, etc.), amide group (for example, Methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group), amino group (example) For example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, anilino group, naphthylamino group, 2-pyridylamino group, etc.), halogen atom (eg, fluorine atom, chlorine) Atom, bromine atom, etc.).

  Among these substituents, an aryl group, an amino group, an amide group, an alkoxycarbonyl group, and a hydroxyl group are preferable.

Examples of the alkylene group for X ² include an ethylene group, trimethylene group, tetramethylene group, propylene group, ethylethylene group, pentamethylene group, hexamethylene group, and 2,2,4-trimethylhexamethylene group.

  Examples of the cycloalkyl group include a cyclopentyl group and a cyclohexyl group.

  Examples of the arylene group include a phenylene group and a naphthylene group.

  Specific examples of the compound represented by the general formula (PMOH) according to the present invention are given below, but the present invention is not limited thereto.

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

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

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

  Other preferable dyes that can be used include, for example, JP 2000-98605, JP 2000-147663, JP 2000-206690, JP 2000-258910, JP 2000-309724, and JP 2001. And spectral sensitizers described in JP-A-042525, JP-A-2002-202598, and JP-A-2000-221790.

(Polymer binder)
The photosensitive layer according to the present invention contains a polymer binder.

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

  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.

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

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

  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.

  In the photosensitive lithographic printing plate material of the present invention, among the above polymer binders, in particular, the N-vinylpyrrolidone homopolymer or copolymer may be contained in the photosensitive layer to solve the problem according to the present invention. Preferred for.

  When a copolymer of N-vinylpyrrolidone is used, the monomer to be copolymerized is not particularly limited, but vinyl acetate can be preferably used. 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.

(Various additives)
In the photosensitive layer according to the present invention, in addition to the above-mentioned various components, in order to prevent unnecessary polymerization of an ethylenic double bond monomer that can be polymerized during production or storage of a photosensitive lithographic printing plate material, It is preferable to add a polymerization 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-tert-butylphenol), N-nitrosophenylhydroxylamine cerium salt, 2-tert-butyl-6- (3-tert-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 total solid content 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.

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

  From the viewpoints of pigment absorption in the above-mentioned photosensitive wavelength region and visible image properties after development, violet pigments and blue pigments are preferably used. Such as, for example, cobalt blue, cerulean blue, alkali blue lake, phonatone blue 6G, Victoria blue lake, metal-free phthalocyanine blue, phthalocyanine blue first sky blue, indanthrene blue, indico, dioxane violet, iso Violanthrone Violet, Indanthrone Blue, Indanthrone BC and the like can be mentioned. Among these, phthalocyanine blue and dioxane violet are more preferable.

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

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

  Moreover, as a solvent used when preparing the photosensitive layer coating solution of the photosensitive layer according to the present invention, for example, in alcohol: polyhydric alcohol derivatives, 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 Preferred examples include methylcyclohexanone and esters: ethyl lactate, butyl lactate, diethyl oxalate, methyl benzoate and the like.

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

Photosensitive layer according to the present invention as the amount per on the ^{support, 0.1g / m 2 ~10g / m} 2 are preferred, especially 0.5g ^{/ m 2} ~5g ^/ m 2 is preferred.

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

  Examples of the support according to the present invention include a metal plate such as aluminum, stainless steel, chromium and nickel, or a laminate obtained by laminating or vapor-depositing the above metal thin film on a plastic film such as a polyester film, a polyethylene film and a polypropylene film. . Moreover, although what hydrophilized the surface, such as a polyester film, a vinyl chloride film, a nylon film, etc. can be used, an aluminum support body is used preferably. In the case of an aluminum support, pure aluminum or an aluminum alloy is used. Various aluminum alloys can be used as the support, and for example, 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.

In the case of using an aluminum support, it is preferable to perform a degreasing treatment in order to remove the rolling oil on the surface prior to roughening (graining treatment). As the degreasing treatment, a degreasing treatment using a solvent such as trichlene or thinner, an emulsion degreasing treatment using an emulsion such as kesilon or triethanol, or the like is used. 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, it 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 amount of aluminum dissolved on the surface is preferably 0.5 to 5 g / m ² . 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 method and the electrochemical surface roughening method may each be used alone to roughen the surface, or the mechanical surface roughening method followed by the electrochemical surface roughening method. You may roughen.

  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, after performing these treatments, water-soluble resins such as polyvinylphosphonic acid, polymers and copolymers having sulfonic acid groups in the side chain, polyacrylic acid, water-soluble metal salts (for example, zinc borate) or Also suitable are those coated with a yellow dye, amine salt or the like. Further, a sol-gel treated substrate in which a functional group capable of causing an addition reaction by a radical as disclosed in JP-A No. 5-304358 is covalently used.

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

  Examples of coating methods for the coating liquid include air doctor coater method, blade coater method, wire bar method, knife coater method, dip coater method, reverse roll coater method, gravure coater method, cast coating method, curtain coater method and extrusion coater method. I can list them.

  The drying temperature of the photosensitive layer is preferably in the range of 60 to 160 ° C, more preferably 70 to 140 ° C, and particularly preferably 80 to 120 ° C.

<Image exposure>
In the present invention, the photosensitive lithographic printing plate material according to the present invention is characterized in that image information is exposed by a laser light source in a temperature range of 50 ° C. to 130 ° C. of the plate surface of the photosensitive lithographic printing plate material at the time of exposure. And

  In the present invention, in the present invention, the temperature of the plate surface of the photosensitive lithographic printing plate material is the nine portions (9 rectangles) obtained by dividing the plate surface of the photosensitive lithographic printing plate material into 9 equal parts in length and width. It refers to the temperature measured by attaching a thermocouple to the center of gravity of each support on the surface having the photosensitive layer with respect to the support. The temperature of the plate surface of the photosensitive lithographic printing plate material can be controlled by temperature setting in each heating device.

  In the present invention, the heating at the time of exposure is preferably performed from 30 seconds before the start of exposure to 60 seconds after the exposure. As a heating device, a device that performs heat treatment using radiant heat such as a ceramic heater, or a device that performs heat treatment using hot air heated by a ceramic heater or the like, irradiates an image recording layer with an electromagnetic wave having a predetermined wavelength generated by a magnetron, A material such as water in the recording layer that resonates and heats (electromagnetic wave heating), or a high frequency magnetic field from an electromagnetic coil may be applied to the metal support to inductively heat the support. It is preferable that the temperature of the printing plate can be adjusted to an arbitrary temperature within the range of 50 ° C to 120 ° C.

  As a light source for recording an image on the photosensitive lithographic printing plate material according to the present invention, laser light having an emission wavelength of 350 to 450 nm is preferably used.

As a light source for exposing the photosensitive lithographic printing plate material according to the present invention, for example, a He—Cd laser (441 nm), a combination of Cr: LiSAF and SHG crystal (430 nm) as a solid laser, and KNbO ₃ as a semiconductor laser system , Ring resonator (430 nm), AlGaInN (350 nm to 450 nm), AlGaInN semiconductor laser (commercially available InGaN-based semiconductor laser 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 exposure is preferably performed with a plate surface energy (energy on the plate material) of 10 μJ / cm ² or more, and the upper limit is 500 μJ / cm ² . More preferably, it is 10-300 microjoule / cm < ² >. For this energy measurement, for example, a laser power meter PDGDO-3W manufactured by OphirOptics can be used.

<< Development processing, lithographic printing plate preparation, printing >>
In the “processing method for photosensitive lithographic printing plate material” of the present invention, as described above, the photosensitive lithographic printing plate material according to the present invention which has been subjected to image exposure by the exposure according to the present invention has a low pH development treatment. As described above, the unexposed area can be removed with the aqueous solution according to the present invention, and a lithographic printing plate can be obtained and printed.

  The “processing method for photosensitive lithographic printing plate material” of the present invention comprises a spectral sensitizer having a maximum absorption at 350 to 450 nm, a polymerization initiator, a co-initiator, a polymerizable monomer, and a polymer bond on a support. A photosensitive lithographic printing plate material having a photosensitive layer containing a material as an outermost layer is exposed to image information with a laser light source in a temperature range of 50 ° C. to 130 ° C. of the plate surface of the photosensitive lithographic printing plate material during exposure, The lithographic printing plate is obtained by removing the unexposed portion with an aqueous solution containing a functional resin and a surfactant and having a pH of 3.0 to 9.0 at 25 ° C.

<Development processing>
(Aqueous solution according to the present invention)
The aqueous solution according to the present invention is an aqueous solution for removing an unexposed portion and contains a water-soluble resin and a surfactant.

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

  In addition, examples of the surfactant according to the present invention include an anionic surfactant and a nonionic surfactant. For example, anionic surfactants include fatty acid salts, abietic acid salts, hydroxyalkane sulfonates, alkane sulfonates, dialkyl sulfosuccinates, linear alkyl benzene sulfonates, branched alkyl benzene sulfonates, alkyl naphthalene sulfones. Acid salts, alkylphenoxy polyoxyethylene propyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, polyoxyethylene aryl ether sulfonates, polyoxyethylene naphthyl ether sulfonates, N-methyl-N-oleyl taurine sodium salts N-alkylsulfosuccinic acid monoamido disodium salts, petroleum sulfonates, nitrated castor oil, sulfated beef tallow oil, sulfate esters of fatty acid alkyl esters, Rualkyl nitrates, polyoxyethylene alkyl ether sulfates, fatty acid monoglyceride sulfates, polyoxyethylene alkylphenyl ether sulfates, polyoxyethylene styryl phenyl ether sulfates, alkyl phosphate esters, polyoxyethylene alkyl ethers Phosphate ester salts, polyoxyethylene alkylphenyl ether phosphate ester salts, partially saponified products of styrene-maleic anhydride copolymer, partially saponified products of olefin-maleic anhydride copolymer, naphthalenesulfonate formalin condensates Etc. Among these, dialkyl sulfosuccinates, alkyl sulfate esters, and alkyl naphthalene sulfonates are particularly preferably used.

  Nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene aryl ethers, polyoxyethylene naphthyl ether, polyoxyethylene polystyryl phenyl ether, polyoxyethylene polyoxy Propylene alkyl ether, glycerin fatty acid partial ester, sorbitan fatty acid partial ester, pentaerythritol fatty acid partial ester, propylene glycol mono fatty acid ester, sucrose fatty acid partial ester, polyoxyethylene sorbitan fatty acid partial ester, polyoxyethylene sorbitol fatty acid moiety Esters, polyethylene glycol fatty acid esters, polyglycerol fatty acid partial esters, polyoxyethylenated ester List oils, polyoxyethylene glycerin fatty acid partial esters, fatty acid diethanolamides, N, N-bis-2-hydroxyalkylamines, polyoxyethylene alkylamines, triethanolamine fatty acid esters, trialkylamine oxides, etc. It is done. Of these, polyoxyethylene alkylphenyl ethers, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene-polyoxypropylene block polymers and the like are preferably used. Fluorine-based and silicon-based anions and nonionic surfactants can also be used.

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

  Two or more of these surfactants can be used in combination. For example, two or more different from each other can be used in combination. For example, a combination of two or more different anionic surfactants or a combination of an anionic surfactant and a nonionic surfactant is preferable. Although the usage-amount of the said surfactant does not need to specifically limit, Preferably it is 0.01-20 mass% of a post-processing liquid.

  The pH of the aqueous solution according to the present invention can be used in the range of 3.0 to 9.0. When using in the acidic range pH 3-6, it adjusts by adding a mineral acid, an organic acid, an inorganic salt, etc. in aqueous solution. The addition amount is preferably 0.01 to 2% by mass. Examples of mineral acids include nitric acid, sulfuric acid, phosphoric acid, and metaphosphoric acid. Examples of the organic acid include citric acid, acetic acid, succinic acid, malonic acid, p-toluenesulfonic acid, tartaric acid, malic acid, lactic acid, levulinic acid, phytic acid, and organic phosphonic acid.

  Further, examples of the inorganic salt include magnesium nitrate, primary sodium phosphate, secondary sodium phosphate, nickel sulfate, sodium hexamethanoate, sodium tripolyphosphate, and the like. You may use together at least 1 sort (s) or 2 or more types, such as a mineral acid, an organic acid, or an inorganic salt. When used in the basic region pH 8 to 9, it can be adjusted to the pH by adding a water-soluble organic base or inorganic base. A water-soluble organic base is preferable, and examples include triethanolamine, diethanolamine, and ethanolamine.

  Moreover, antiseptic | preservative, an antifoamer, etc. can be added to the aqueous solution which concerns on this invention.

  For example, as a preservative, phenol or a derivative thereof, o-phenylphenol, p-chlorometacresol, hydroxybenzoic acid alkyl ester, formalin, imidazole derivative, sodium dehydroacetate, 4-isothiazolin-3-one derivative, benzoisothiazoline-3- ON, benztriazole derivatives, amiding anidine derivatives, quaternary ammonium salts, derivatives of pyridine, quinoline, guanidine, diazine, triazole derivatives, oxazole, oxazine derivatives and the like. A preferable addition amount is an amount that exerts a stable effect on bacteria, molds, yeasts, etc., and varies depending on the type of bacteria, molds, yeasts, but 0.01% with respect to the plate surface protective agent at the time of use. The range of ˜4% by mass is preferable, and it is preferable to use two or more kinds of preservatives in combination so as to be effective against various molds and sterilization. As the antifoaming agent, a silicon antifoaming agent is preferable. Among them, emulsification dispersion type and solubilization can be used. Preferably the range of 0.01-1.0 mass% is optimal.

  Further, a chelate compound may be added. Preferred chelate compounds include, for example, ethylenediaminetetraacetic acid, potassium salt thereof, sodium salt thereof; diethylenetriaminepentaacetic acid, potassium salt thereof, sodium salt thereof; triethylenetetraminehexaacetic acid, sodium salt thereof; ethylenediamine disuccinic acid, potassium salt thereof. Triethylenetetramine hexaacetic acid, potassium salt thereof, sodium salt thereof, hydroxyethylethylenediaminetriacetic acid, potassium salt thereof, sodium salt thereof: nitrilotriacetic acid, sodium salt thereof; 1-hydroxyethane-1,1-diphosphone Acids, potassium salts, sodium salts; organic phosphonic acids or phosphonoalkanetricarboxylic acids such as aminotri (methylenephosphonic acid), potassium salts, sodium salts, etc. It can be mentioned. An organic amine salt is also effective in place of the sodium salt and potassium salt of the chelating agent. These chelating agents are selected so that they are stably present in the gum solution composition and do not impair the printability. The addition amount is suitably 0.001 to 1.0% by mass.

  In addition to the above components, a sensitizer can be added as necessary. For example, hydrocarbons such as turpentine oil, xylene, toluene, low heptane, solvent naphtha, kerosene, mineral spirit, petroleum fraction having a boiling point of about 120 ° C to about 250 ° C, such as dibutyl phthalate, dihebutyl phthalate, di-n-octyl Phthalic acid diester agents such as phthalate, di (2-ethylhexyl) phthalate, dinonyl phthalate, didecyl phthalate, dilauryl phthalate, butyl benzyl phthalate, such as dioctyl adipate, butyl glycol adipate, dioctyl azelate, dibutyl sebacate, di ( 2-ethylhexyl) aliphatic dibasic acid esters such as sebacate and dioctyl sebacate, epoxidized triglycerides such as epoxidized soybean oil, such as tricresyl phosphate, trioctylfolate Feto, phosphoric acid esters such as tris chloroethyl phosphate, for example, freezing point, such as benzoic acid esters of benzyl benzoate and at 15 ℃ below boiling point at one atmosphere include 300 ° C. or more plasticizers. Furthermore, caproic acid, enanthic acid, caprylic acid, helargonic acid, capric acid, undecyl acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachic acid, behenic acid, lignoserine Saturated fatty acids such as acid, serotic acid, heptacosanoic acid, montanic acid, melicinic acid, lactelic acid, isovaleric acid, and acrylic acid, crotonic acid, isocrotonic acid, undecylenic acid, oleic acid, elaidic acid, celetic acid, nillic acid, buteticidin Examples also include unsaturated fatty acids such as acid, sorbic acid, linoleic acid, linolenic acid, arachidonic acid, propiolic acid, stearolic acid, sardine acid, talylic acid and licanoic acid. More preferably, it is a fatty acid that is liquid at 50 ° C., more preferably 5 to 25 carbon atoms, and most preferably 8 to 21 carbon atoms. These sensitizers can be used alone or in combination of two or more. A preferable range for the amount used is 0.01 to 10% by mass, and a more preferable range is 0.05 to 5% by mass.

  In the present invention, the photosensitive lithographic printing plate material of the present invention is prepared from 350 nm in a temperature range of 50 ° C. to 130 ° C. of the plate surface of the photosensitive lithographic printing plate material at the time of exposure when preparing the lithographic printing plate. The unexposed area after exposing and recording image information with a laser light source having an emission wavelength in the range of 450 nm contains a water-soluble resin and a surfactant and has a pH of 3.0 to 9.0 at 25 ° C. It is characterized in that it can be removed by an aqueous solution (which is a lithographic printing plate), but various means can be adopted to enable the unexposed portion to be suitably removed.

  For example, in the present invention, it is one of the preferred embodiments that the unexposed portion can be removed by selecting an appropriate condition for the type and content of the polymerizable monomer contained in the photosensitive layer of the photosensitive lithographic printing plate material. is there. As an example of this embodiment, a polymerizable compound having at least a hydroxyl group in the molecule is selected as the polymerizable monomer to be contained in the photosensitive layer, and a homopolymer or copolymer of at least N-vinylpyrrolidone is used as the polymer binder. It is preferable to select a coalescence.

  Further, in order to make it possible to remove the unexposed portion, as another means, the photosensitive lithographic printing material according to the present invention has a plate surface temperature of 50 ° C. to 130 ° C. during exposure to the photosensitive lithographic printing material. After exposing and recording image information with a laser light source in a range, a method of removing the unexposed portion with the aqueous solution through a step of heating so that the temperature of the plate surface is 80 ° C. to 160 ° C. is preferable.

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

  In the step of removing the unexposed area with an aqueous solution containing a water-soluble resin and a surfactant and having a pH of 3.0 to 9.0 at 25 ° C., a development process for a normal general photosensitive lithographic printing plate material It is possible to use a developing bath of an automatic developing machine used in the above. The developing bath is preferably provided with a mechanism for rubbing the plate surface with a roller-like brush and has a mechanism capable of adjusting the aqueous solution to a constant temperature. It is preferable that the temperature adjustment can be arbitrarily set within a range of 20 to 35 ° C. Further, a mechanism for automatically replenishing the required amount of the aqueous solution is provided. Preferably, the aqueous solution in excess of a certain amount is provided with a mechanism for discharging, preferably a mechanism for detecting plate passing. Preferably, a mechanism for estimating the processing area of the plate based on the detection of the plate is provided, preferably replenishment of the replenisher to be replenished based on the detection of the plate and / or the estimation of the processing area A mechanism for controlling the amount and / or replenishment timing is provided, preferably a mechanism for controlling the temperature of the aqueous solution is provided, and preferably a mechanism for detecting the pH and / or conductivity of the aqueous solution is provided. Preferably, a mechanism for controlling the replenishment amount and / or replenishment timing of the replenisher and / or water to be replenished based on the pH and / or conductivity of the aqueous solution is provided.

<Printing using planographic printing plates>
Printing can be performed using a lithographic printing plate obtained by the development process.

  When the lithographic printing plate precursor is exposed imagewise with a laser and then developed, in the exposed portion of the image recording layer, the image recording layer cured by exposure forms an oil-based ink receiving portion having an oleophilic surface. On the other hand, in the unexposed area, the uncured image recording layer is dissolved or dispersed and removed by development, and a hydrophilic surface is exposed in that area. As a result, the aqueous component adheres to the exposed hydrophilic surface, and the oil-based ink is deposited on the image recording layer in the exposed area, and printing is started. Here, the water-based component or oil-based ink may be first supplied to the plate surface, but the oil-based ink is first used in order to prevent the water-based component from being contaminated by the image recording layer in the unexposed area. It is preferable to supply. As the aqueous component and the oil-based ink, a dampening water for normal lithographic printing and a printing ink are used.

<On-press development printing>
In the present invention, the photosensitive lithographic printing plate material according to the present invention is used, and the exposure method according to the present invention, that is, the image is exposed to the specific temperature according to the present invention while being heated, so that on-press development is performed. Printing, i.e., image exposure and on-press development printing (so-called direct printing without taking out the lithographic printing plate) can be suitably performed.

  The method for preparing a lithographic printing plate according to the present invention comprises a photosensitive layer containing a spectral sensitizer having an absorption maximum at 350 to 450 nm, a polymerization initiator, a coinitiator, a polymerizable monomer, and a polymer binder on a support. The photosensitive lithographic printing plate material having the outermost layer is exposed to image information with a laser light source at a temperature of the plate surface of the photosensitive lithographic printing plate material at the time of exposure of 50 ° C. to 130 ° C. And the non-image portion is removed. Then, on-press printing can be continued.

  After the lithographic printing plate precursor is imagewise exposed with a laser, printing is performed by supplying an aqueous component and an oil-based ink without passing through a development processing step such as a wet development processing step. The image recording layer thus formed forms an oil-based ink receiving portion having an oleophilic surface. On the other hand, in the unexposed area, the uncured image recording layer is dissolved or dispersed and removed by the supplied aqueous component and / or oil-based ink, and a hydrophilic surface is exposed in the area. As a result, the aqueous component adheres to the exposed hydrophilic surface, and the oil-based ink is deposited on the image recording layer in the exposed area, and printing is started. Here, the water-based component or oil-based ink may be first supplied to the plate surface, but the oil-based ink is first used in order to prevent the water-based component from being contaminated by the image recording layer in the unexposed area. It is preferable to supply. As the aqueous component and the oil-based ink, a dampening water for normal lithographic printing and a printing ink are used.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these. Unless otherwise specified, “part” in the examples represents “part by mass”.

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

(A) The aluminum plate was subjected to an etching process 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 0.3 g / m ^{2 of the} aluminum plate. 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. The electrolytic solution at this time contains 1.1% by mass of hydrochloric acid, 0.5% by mass of aluminum ions, and 0.5% by mass of acetic acid. The temperature was 21 ° C. The AC power source was subjected to electrochemical surface roughening treatment using a sine wave alternating current having a time TP of 2 msec until the current value reached a peak from zero, using a carbon electrode as a counter electrode. The current density was 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 anodizing 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 apparatus, 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, and the plate-like aluminum in the first electrolysis unit. 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 0.4 mass% polyvinylphosphonic acid solution for 30 seconds, and was hydrophilized. The temperature was 85 ° 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 0.65 μm.

(Preparation of photosensitive lithographic printing plate material 1)
On the support, a photopolymerizable photosensitive layer coating solution having the following composition was applied with a wire bar so that the drying rate was 1.5 g / m ² , and dried at 95 ° C. for 1.5 minutes. Plate material 1 (photopolymerized photosensitive layer-coated sample) was prepared.

(Photopolymerizable photosensitive layer coating solution)
Binder A (the following structure) 5.0 parts Polymerizable monomer (dipentaerythritol pentaacrylate, SR399E manufactured by Nippon Kayaku Co., Ltd.) 5.0 parts Sensitizing dye A (the following structure) 0.7 part Polymerization initiator: 2 , 4,5,2 ', 4', 5'-hexaphenylbiimidazole
0.5 part Co-initiator A (the following structure) 0.25 part Acetylene-based surfactant (Surfinol 465; manufactured by Air Products) 0.5 part Phthalocyanine pigment dispersion MHI # 454 (manufactured by Gokoku Dye) 3.0 Part polyoxyethylene-polyoxypropylene condensate 0.04 part tetraethylamine hydrochloride 0.01 part 1-methoxy-2-propanol 135 parts

(Preparation of photosensitive lithographic printing plate material 2)
In the preparation of the photosensitive lithographic printing plate material 1, after the photosensitive layer is applied, a protective layer having the following formulation is further applied so that the dry coating amount is 2 g / m ² and dried at 120 ° C. for 1 minute. A lithographic printing plate material 2 was prepared.

(Protective layer)
Polyvinyl alcohol (saponification degree 98 mol%, polymerization degree 800) 80 parts Polyvinylpyrrolidone (molecular weight 50,000) 19.5 parts Surfactant (Surfinol 465: manufactured by Nissin Chemical Industry Co., Ltd.) 0.5 part Water 900 parts << Treatment Evaluation
<sensitivity>
(exposure)
The photosensitive lithographic printing plate material was exposed at 2400 dpi (dpi represents the number of dots per 2.54 cm) with a 405 nm, 60 mW laser at the plate surface temperature shown in Table 1. In the exposure, original image data of 100% image portion, Times New Rohman font, 3 to 10 point size, alphabet uppercase and lowercase letters were used as the exposure pattern.

(Development, preparation of lithographic printing plate)
The photosensitive lithographic printing plate material after the exposure was developed with an aqueous solution (1) having the following composition at 25 ° C. for the development time shown in Table 1 to obtain a lithographic printing plate.

  In the 100% image area recorded on the plate surface of the obtained lithographic printing plate, the minimum exposure energy amount at which no film reduction is observed is taken as the recording energy and is shown as an index indicating the sensitivity of the photosensitive lithographic printing plate material. The smaller the recording energy, the higher the sensitivity.

(Aqueous solution (1))
White dextrin 5.0% by mass
Hydroxypropyl etherified starch 10.0% by mass
Gum arabic 1.0% by mass
1st Ammon Phosphate 0.1% by mass
Sodium dilauryl succinate 0.15% by mass
Polyoxyethylene naphthyl ether 0.5% by mass
Polyoxyethylene polyoxypropylene block copolymer (ethylene oxide ratio 50 mol%, molecular weight 5000) 0.3 mass%
Ethylene glycol 1.0% by mass
1,2 benzoisothiazolin-3-one 0.005 mass%
Phosphoric acid (addition of pH = 3.0 at 25 ° C)
<Non-image area stain resistance>
About the obtained lithographic printing plate, using a printing machine manufactured by Heidelberg, magenta ink, the printed matter was visually observed after printing 5000 sheets on coated paper, and the presence or absence of soiling on the non-image area was confirmed. As an index indicating the stain resistance of the image portion, it is evaluated according to the following criteria. Rank 5 is a state where no soiling is observed. Less than rank 3 is soil that cannot be used.

<Sludge generation resistance>
The unexposed photosensitive lithographic printing plate material is subjected to 25 m ² / L development treatment, the treated solution is collected and heated at 40 ° C. for 2 weeks, and sludge is visually observed. Evaluated according to The rank of 3 or more is a level that is not problematic for practical use.

  The results are shown in Table 1.

  As is apparent from Table 1, in the case of the present invention, it is found that the sensitivity is excellent, and the non-image area is also excellent in resistance to scumming and sludge generation.

  In the case of the present invention, although a photopolymerization type photosensitive lithographic printing plate material of short wave light (wavelength 350 to 450 nm, low energy) image exposure type is used, a specific photosensitive lithographic printing plate material is used. By improving the image sensitivity by image exposure (image forming method), it is particularly sensitive to non-image area scumming resistance and sludge generation resistance. It can be seen that a printing plate preparation method and a processing method of a photosensitive lithographic printing plate material (preparation method of a lithographic printing plate (low pH development treatment, preparation of a lithographic printing plate, printing method)) can be provided.

Example 2
<Exposure, on-press development printing>
The photosensitive lithographic printing plate material described in Example 1 (the type described in Table 2) was exposed as described in Example 1 and then subjected to the development process without being developed. The cylinder of the DAIYA1F-1 printer manufactured by Mitsubishi Heavy Industries, Ltd. And printing using printing ink (soybean oil ink “Naturalis 100” manufactured by Dainippon Ink & Chemicals, Inc.) and fountain solution (H ink SG-51 concentration 1.5% by mass manufactured by Tokyo Ink Co., Ltd.) Went.

<Non-image area stain resistance>
After performing the above-mentioned << exposure, on-press development printing >>, after printing 5000 sheets of coated paper, the printed matter is visually observed to confirm the presence or absence of non-image area scumming. Evaluated according to the criteria. Rank 5 is a state where no soiling is observed. Less than rank 3 is soil that cannot be used.

<White light safety>
An unexposed photosensitive lithographic printing plate material (types listed in Table 2) is placed under a white fluorescent lamp, exposed at a light quantity of 1000 Lx, and then subjected to on-machine development printing, and the printed matter is visually observed after printing. The exposure time at which no ink smear occurs is measured, and is shown as an indicator of white light safety. The longer the time, the better the white light safety.

<Press life>
The photosensitive lithographic printing plate material described in Example 1 (the type described in Table 2) was subjected to the above-mentioned “exposure, on-machine development printing”, and after the unexposed area was removed on the printing machine, the solid on the printing paper The number of printed sheets when the density of the portion is reduced by 0.1 is shown as an index indicating printing durability.

  The results are shown in Table 2.

  As is apparent from Table 2, in the case of the present invention, it is understood that the non-image area is excellent in stain resistance, white light safety printing durability, and printing durability.

  In the case of the present invention, although a photopolymerization type photosensitive lithographic printing plate material of short wave light (wavelength 350 to 450 nm, low energy) image exposure type is used, a specific photosensitive lithographic printing plate material is used. A high-sensitivity image exposure method (image forming method), and in particular, a high-sensitivity printing press for on-press development, excellent printing durability, and excellent white light safety. It can be seen that (further, on-press development lithographic printing method) can be provided.

Claims (3)

A photosensitive lithographic printing plate having a photosensitive layer containing a spectral sensitizer having a maximum absorption at 350 to 450 nm, a polymerization initiator, a co-initiator, a polymerizable monomer, and a polymer binder as an outermost layer on a support. A method for preparing a lithographic printing plate, comprising the step of exposing image information with a laser light source at a temperature of 50 ° C to 130 ° C of the plate surface of the photosensitive lithographic printing plate material at the time of exposure. A photosensitive lithographic printing plate having a photosensitive layer containing a spectral sensitizer having a maximum absorption at 350 to 450 nm, a polymerization initiator, a co-initiator, a polymerizable monomer, and a polymer binder as an outermost layer on a support. The material is exposed to image information with a laser light source at a temperature of the plate surface of the photosensitive lithographic printing plate material at the time of exposure of 50 ° C. to 130 ° C., and contains a water-soluble resin and a surfactant and has a pH at 25 ° C. A method for treating a photosensitive lithographic printing plate material, wherein an unexposed portion is removed with an aqueous solution having an A of 3.0 to 9.0 to obtain a lithographic printing plate. A photosensitive lithographic printing plate having a photosensitive layer containing a spectral sensitizer having a maximum absorption at 350 to 450 nm, a polymerization initiator, a co-initiator, a polymerizable monomer, and a polymer binder as an outermost layer on a support. The material is exposed to image information with a laser light source in the temperature range of the plate surface of the photosensitive lithographic printing plate material at the time of exposure to 50 ° C to 130 ° C, and printing ink and fountain solution are supplied to remove non-image areas. A method for preparing a lithographic printing plate, comprising: