JP2017013318A - Planographic printing original plate and method for producing planographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a planographic printing original plate capable of obtaining a planographic printing plate having excellent printing durability and plate inspection performance and to provide a method for producing a planographic printing plate using the planographic printing original plate.SOLUTION: There is provided a planographic printing original plate which comprises an intermediate layer and a photosensitive layer in this order on an aluminum support, wherein the photosensitive layer contains a polymerization initiator as component A and a polymerizable compound as component B and the intermediate layer contains a sensitizing dye as component D and a polymer having a repeating unit having a structure capable of interacting with a surface of the aluminum support as component E.SELECTED DRAWING: None

Description

  The present invention relates to a lithographic printing plate precursor and a lithographic printing plate making method.

  Currently, lithographic printing plates are obtained by CTP (computer to plate) technology. That is, a lithographic printing plate can be obtained by scanning and exposing a lithographic printing plate precursor directly using a laser or a laser diode without a lith film, and developing it.

  Along with the above technical progress, problems related to the lithographic printing plate precursor have been changed to improvements in image forming characteristics, printing characteristics, physical characteristics and the like corresponding to the CTP technology. In addition, due to increasing interest in the global environment, environmental issues related to waste liquids associated with wet processing such as development processing have been highlighted as another issue related to lithographic printing plate precursors.

  For the above environmental problems, simplification and no processing of development or plate making are directed. As one simple plate making method, a method called “on-press development” is performed. That is, after the exposure of the lithographic printing plate precursor, conventional development is not performed, but it is mounted on a printing machine as it is, and unnecessary portions of the photosensitive layer are removed at the initial stage of a normal printing process.

In the case of an on-press development type or an unprocessed (non-development) type lithographic printing plate precursor that does not undergo development processing, there is no image on the printing plate at the stage of attaching the printing plate to the printing press, and plate inspection cannot be performed. In particular, whether or not it is possible to determine that a register mark (register mark) that serves as a registration mark in multi-color printing is drawn is important for the printing operation. Therefore, on-machine development type or non-processed (no development) type lithographic printing plate precursor is a means for confirming an image at the stage of exposure, that is, a so-called print-out image in which an exposed area is colored or decolored (hereinafter referred to as “printed image”). , Also called plate inspection).
As a conventional lithographic printing plate precursor, one described in Patent Document 1 is known.

JP 2013-199089 A

  The problem to be solved by the present invention is to provide a lithographic printing plate precursor from which a lithographic printing plate excellent in printing durability and plate inspection can be obtained, and to make a lithographic printing plate using the lithographic printing plate precursor Is to provide a method.

The above-described problems of the present invention have been solved by the means described in <1>, <10> or <11> below. It is described below together with <2> to <9> which are preferred embodiments.
<1> On an aluminum support, it has an intermediate layer and a photosensitive layer in this order, and the photosensitive layer contains a polymerizable compound as component A, a polymerization initiator, and component B, and A lithographic printing plate precursor characterized in that the intermediate layer contains, as component D, a sensitizing dye, and as component E, a polymer having a repeating unit having a structure that interacts with the surface of the aluminum support,
<2> The lithographic printing plate precursor as described in <1>, wherein the component D comprises a compound represented by the following formula 1:

In Formula 1, X ¹ represents a hydrogen atom, a halogen atom, or a group represented by the following Formulas 2 to 6, Za represents a counter ion that neutralizes charge, and R ¹ and R ² are each independently Represents a hydrocarbon group having 1 to 12 carbon atoms, Ar ¹ and Ar ² represent a group forming an aromatic ring, and Y ¹ and Y ² each independently represent a sulfur atom or a dialkylmethylene having 1 to 12 carbon atoms. R ³ and R ⁴ each independently represents a hydrocarbon group having 1 to 20 carbon atoms, and R ^{5 to} R ⁸ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms. ,

In formula 2 to formula 6, L ^{1 to} L ⁴ may each independently contain a carbonyl group, a sulfonyl group, or —N (R ^N ) —, ═N—, —S—, or —O—. represents a hydrocarbon group having a carbon number of 1 to 20, R ^N represents a hydrogen atom, an alkyl group or an aryl group, Ra represents an alkyl group, an aryl group, an amino group, or a halogen atom, n1 is 0 to 5 Zb represents a counter ion that neutralizes the charge, ● represents a binding site with another structure,
<3> The lithographic printing plate precursor as described in <2>, wherein the compound represented by formula 1 has a zwitterionic structure,
<4> The lithographic printing plate precursor as described in <2> or <3>, wherein at least one of R ³ and R ⁴ is a group represented by the following formula 7:

In Formula 7, L ⁵ represents a divalent hydrocarbon group having 1 to 6 carbon atoms, A ⁻ represents a carboxylate anion, a sulfonate anion, a phosphonate anion, or a phosphinate anion, and ● represents an N atom Represents the binding site,
<5> The lithographic printing plate precursor as described in any one of <2> to <4>, wherein X ¹ is a group represented by the following formula 8.

In Formula 8, R ⁹ and R ¹⁰ each independently represent a hydrogen atom, an alkyl group or an aryl group, X ² represents an onium group, and ● represents a binding site with another structure.
<6> The lithographic printing plate precursor as described in <5>, wherein X ² is a group represented by the following formula 9:

In Formula 9, each R ¹¹ independently represents a halogen atom, an alkyl group, an aryl group, a hydroxy group, or an alkoxy group, and a plurality of R ¹¹ may be linked to form a ring, and n2 is 0 Represents an integer of ˜4, R ¹² represents an alkyl group or an aryl group, Zc represents a counter ion that neutralizes charge, and ● represents a binding site with another structure,
<7> The lithographic printing plate precursor as described in any one of <1> to <6>, wherein the intermediate layer contains a polymerization initiator as component G.
<8> As the structure in which component E interacts with the surface of the aluminum support, a carboxylic acid structure, a carboxylate structure, a sulfonic acid structure, a sulfonate structure, a phosphonic acid structure, a phosphonate structure, and a phosphate structure Or a lithographic printing plate precursor according to any one of <1> to <7>, comprising a phosphate ester salt structure,
<9> The lithographic printing plate precursor as described in any one of <1> to <8>, wherein Component E has a repeating unit having a zwitterionic structure,
<10> An exposure process for imagewise exposing the lithographic printing plate precursor according to any one of <1> to <9>, and an unexposed portion of the lithographic printing plate precursor that has been imagewise exposed to a pH of 2 A plate development method of a lithographic printing plate comprising a solution development treatment step of removing an unexposed portion with 12 developer;
<11> An exposure process for imagewise exposing the lithographic printing plate precursor according to any one of <1> to <9>, and an unexposed portion of the lithographic printing plate precursor that has been imagewise exposed to a printing machine A plate making method of a lithographic printing plate comprising an on-press development process step of supplying and removing printing ink and / or fountain solution.

  According to the present invention, a lithographic printing plate precursor from which a lithographic printing plate excellent in printing durability and plate inspection properties can be obtained is provided, and a lithographic printing plate making method using the lithographic printing plate precursor is provided. I was able to.

Hereinafter, the present invention will be described in detail.
In addition, in this specification, description of "xx-yy" represents the numerical range containing xx and yy.
“(Meth) acrylate” and the like are synonymous with “acrylate and / or methacrylate” and the like.
In the present invention, “mass%” and “wt%” are synonymous, and “part by mass” and “part by weight” are synonymous.
Moreover, in this invention, the combination of a preferable aspect is a more preferable aspect.
In the present specification, regarding the notation of the group in the compound represented by the formula, when there is no substitution or no substitution, the above group can further have a substituent unless otherwise specified. In addition to an unsubstituted group, a group having a substituent is also included. For example, in the formula, if there is a description that “R represents an alkyl group, an aryl group or a heterocyclic group”, “R is an unsubstituted alkyl group, a substituted alkyl group, an unsubstituted aryl group, a substituted aryl group, an unsubstituted group” Represents a heterocyclic group or a substituted heterocyclic group.
In the present specification, unless otherwise specified, the alkyl group may be linear, branched or a ring structure.
In the present specification, unless otherwise specified, the weight average molecular weight (Mw, also referred to as “mass average molar mass”) is a value measured as a polystyrene converted value by the GPC method.

(Lithographic printing plate precursor)
The lithographic printing plate precursor according to the invention has an intermediate layer and a photosensitive layer in this order on an aluminum support, and the photosensitive layer comprises a polymerization initiator as component A and a polymerizable compound as component B. And the intermediate layer contains, as component D, a sensitizing dye and, as component E, a polymer having a repeating unit having a structure that interacts with the surface of the aluminum support.
Further, the lithographic printing plate precursor according to the invention may be a so-called on-machine development type lithographic printing plate precursor in which development processing is performed by on-machine development, and the development processing is performed by development using a developer. It may be a developer-processed lithographic printing plate precursor.

As a result of intensive studies, the present inventors have found that the lithographic printing plate precursor having the above-described configuration is excellent in printing durability. The detailed mechanism is unknown, but by including component D in the intermediate layer, the amount of radicals generated at the interface between the intermediate layer and the photosensitive layer is increased, and the interfacial adhesion is improved. I guess that will improve.
Further, since the lithographic printing plate precursor according to the invention contains a sensitizing dye as component D in the intermediate layer, the exposed lithographic printing plate precursor has improved the visibility of the exposed portion, and the plate inspection It has also been found that it has an effect of being excellent in properties.
Furthermore, the present inventors, when a photosensitive layer containing a sensitizing dye is used, in the lithographic printing plate precursor after exposure, the visibility of the exposed portion is further improved, and the plate inspection property is further improved. It was also found that

<Aluminum support>
The aluminum support (hereinafter also simply referred to as “support”) that can be used in the lithographic printing plate precursor according to the invention is not particularly limited, and examples thereof include known lithographic printing plate precursor aluminum supports. . As the support, an aluminum plate which has been roughened and anodized by a known method is preferable.
If necessary, the aluminum plate is further subjected to micropore enlargement treatment or sealing treatment of an anodized film described in JP-A Nos. 2001-253181 and 2001-322365, U.S. Pat. No. 2,714, Surface hydrophilization treatment with alkali metal silicate as described in US Pat. Nos. 066, 3,181,461, 3,280,734 and 3,902,734, US The surface hydrophilization treatment with polyvinyl phosphonic acid or the like as described in the specifications of Patent Nos. 3,276,868, 4,153,461 and 4,689,272 is appropriately selected. Can be done.
The support preferably has a center line average roughness of 0.10 to 1.2 μm.

  If necessary, the support is provided with an organic polymer compound described in JP-A-5-45885 or JP-A-6-35174 on the surface opposite to the surface on which the image forming layer is formed. A backcoat layer containing a silicon alkoxy compound can be provided.

<Photosensitive layer>
The photosensitive layer used in the present invention contains a polymerization initiator as component A and a polymerizable compound as component B.
The photosensitive layer used in the present invention preferably contains 0.1 to 50% by mass of component A and 5 to 75% by mass of component B with respect to the total solid content of the photosensitive layer.
In addition, the photosensitive layer used in the present invention preferably contains a binder polymer, a sensitizing dye, a reducing agent, polymer particles, or other components.
The total solid content is the total amount of components excluding volatile components such as a solvent in the composition and the layer.

[Component A: Polymerization initiator]
Component A: Polymerization initiator used in the photosensitive layer of the present invention is a compound that generates polymerization initiation species such as radicals and cations by energy of light, heat, or both, and is a known thermal polymerization initiator, bond dissociation A compound having a bond with small energy, a photopolymerization initiator, and the like can be appropriately selected and used.
As the polymerization initiator, a radical polymerization initiator is preferable, and an onium salt is more preferable.
Further, the polymerization initiator is preferably an infrared photosensitive polymerization initiator.
A polymerization initiator may be used individually by 1 type, and may use 2 or more types together.
Examples of the radical polymerization initiator include (a) an organic halide, (b) a carbonyl compound, (c) an azo compound, (d) an organic peroxide, (e) a metallocene compound, (f) an azide compound, (g ) Hexaarylbiimidazole compound, (h) disulfone compound, (i) oxime ester compound, (j) onium salt compound.

As the (a) organic halide, for example, compounds described in paragraphs 0022 to 0023 of JP-A-2008-195018 are preferable.
(B) As the carbonyl compound, for example, compounds described in paragraph 0024 of JP-A-2008-195018 are preferable.
(C) As the azo compound, for example, an azo compound described in JP-A-8-108621 can be used.
(D) As the organic peroxide, for example, compounds described in paragraph 0025 of JP-A-2008-195018 are preferable.
As the (e) metallocene compound, for example, the compound described in paragraph 0026 of JP-A-2008-195018 is preferable.
(F) Examples of the azide compound include compounds such as 2,6-bis (4-azidobenzylidene) -4-methylcyclohexanone.
(G) As the hexaarylbiimidazole compound, for example, the compound described in paragraph 0027 of JP2008-195018A is preferable.
Examples of (h) disulfone compounds include compounds described in JP-A Nos. 61-166544 and 2002-328465.
(I) As the oxime ester compound, for example, compounds described in paragraphs 0028 to 0030 of JP-A-2008-195018 are preferable.

  Among the above polymerization initiators, oxime esters and onium salts are preferable from the viewpoint of curability, and iodonium salts, sulfonium salts and azinium salts are more preferable. Moreover, when using for a lithographic printing plate precursor, iodonium salts and sulfonium salts are particularly preferred. Specific examples of these compounds are shown below, but the present invention is not limited thereto.

  As an example of the iodonium salt, a diphenyl iodonium salt is preferable, and a diphenyl iodonium salt substituted with an electron donating group such as an alkyl group or an alkoxyl group is particularly preferable, and an asymmetric diphenyl iodonium salt is preferable. Specific examples include diphenyliodonium = hexafluorophosphate, 4-methoxyphenyl-4- (2-methylpropyl) phenyliodonium = hexafluorophosphate, 4- (2-methylpropyl) phenyl-p-tolyliodonium = hexa. Fluorophosphate, 4-hexyloxyphenyl-2,4,6-trimethoxyphenyliodonium = hexafluorophosphate, 4-hexyloxyphenyl-2,4-diethoxyphenyliodonium = tetrafluoroborate, 4-octyloxy Phenyl-2,4,6-trimethoxyphenyliodonium = 1-perfluorobutanesulfonate, 4-octyloxyphenyl-2,4,6-trimethoxyphenyliodonium = hexafluorophosphate, bis ( -t- butylphenyl) iodonium hexafluorophosphate and the like.

  As an example of the sulfonium salt, a triarylsulfonium salt is preferable, and an electron-withdrawing group, for example, a triarylsulfonium salt in which at least a part of groups on the aromatic ring is substituted with a halogen atom is preferable, and on the aromatic ring. Triarylsulfonium salts having a total number of halogen atom substitutions of 4 or more are more preferred. Specific examples include triphenylsulfonium = hexafluorophosphate, triphenylsulfonium = benzoylformate, bis (4-chlorophenyl) phenylsulfonium = benzoylformate, bis (4-chlorophenyl) -4-methylphenylsulfonium = tetrafluoro. Borate, tris (4-chlorophenyl) sulfonium = 3,5-bis (methoxycarbonyl) benzenesulfonate, tris (4-chlorophenyl) sulfonium = hexafluorophosphate, tris (2,4-dichlorophenyl) sulfonium = hexafluorophos Fart.

  The content of the polymerization initiator is preferably 0.1 to 50% by mass, more preferably 0.5 to 30% by mass, and particularly preferably 0.8 to 20% by mass with respect to the total solid content of the photosensitive layer. .

[Component B: Polymerizable compound]
The photosensitive layer used in the present invention contains a polymerizable compound. The lithographic printing plate precursor according to the invention having a photosensitive layer containing a polymerizable compound is a so-called negative lithographic printing plate precursor having a photosensitive layer having a function of polymerization and curing by application of heat and / or exposure.
The polymerizable compound used in the photosensitive layer of the present invention may be, for example, a radical polymerizable compound or a cationic polymerizable compound, but an addition polymerizable compound having at least one ethylenically unsaturated bond. Preferably, it is (ethylenically unsaturated compound). The ethylenically unsaturated compound is preferably a compound having at least one terminal ethylenically unsaturated bond, and more preferably a compound having two or more terminal ethylenically unsaturated bonds. The polymerizable compound has a chemical form such as a monomer, a prepolymer, that is, a dimer, a trimer or an oligomer, or a mixture thereof.

  Examples of monomers include unsaturated carboxylic acids (for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc.), esters and amides thereof, preferably unsaturated carboxylic acids. Esters of an acid and a polyhydric alcohol compound and amides of an unsaturated carboxylic acid and a polyamine compound are used. Also, addition reaction products of unsaturated carboxylic acid esters or amides having a nucleophilic substituent such as hydroxy group, amino group, mercapto group and the like with monofunctional or polyfunctional isocyanates or epoxies, and monofunctional or polyfunctional A dehydration condensation reaction product with a functional carboxylic acid is also preferably used. In addition, an unsaturated carboxylic acid ester or amide having an electrophilic substituent such as an isocyanate group or an epoxy group and an addition reaction product of a monofunctional or polyfunctional alcohol, amine or thiol, further a halogen atom, A substitution reaction product of an unsaturated carboxylic acid ester or amide having a leaving substituent such as a tosyloxy group and a monofunctional or polyfunctional alcohol, amine or thiol is also suitable. As another example, a compound group in which the unsaturated carboxylic acid is replaced with unsaturated phosphonic acid, styrene, vinyl ether or the like can be used. These are disclosed in JP-T-2006-508380, JP-A-2002-287344, JP-A-2008-256850, JP-A-2001-342222, JP-A-9-179296, JP-A-9-179297. JP-A-9-179298, JP-A-2004-294935, JP-A-2006-243493, JP-A-2002-275129, JP-A-2003-64130, JP-A-2003-280187, It is described in Japanese Laid-Open Patent Publication No. 10-333321.

  Specific examples of the monomer of the ester of a polyhydric alcohol compound and an unsaturated carboxylic acid include acrylic acid esters such as ethylene glycol diacrylate, 1,3-butanediol diacrylate, tetramethylene glycol diacrylate, propylene glycol diacrylate, Examples include trimethylolpropane triacrylate, hexanediol diacrylate, tetraethylene glycol diacrylate, pentaerythritol tetraacrylate, sorbitol triacrylate, isocyanuric acid ethylene oxide (EO) -modified triacrylate, and polyester acrylate oligomer. Methacrylic acid esters include tetramethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, ethylene glycol dimethacrylate, pentaerythritol trimethacrylate, bis [p- (3-methacryloxy-2-hydroxypropoxy) phenyl] Examples include dimethylmethane and bis [p- (methacryloxyethoxy) phenyl] dimethylmethane. Specific examples of amide monomers of polyvalent amine compounds and unsaturated carboxylic acids include methylene bis-acrylamide, methylene bismethacrylamide, 1,6-hexamethylene bisacrylamide, 1,6-hexamethylene bismethacrylamide, Examples include diethylenetriamine trisacrylamide, xylylene bisacrylamide, and xylylene bismethacrylamide.

Also suitable are urethane-based addition-polymerizable compounds produced using an addition reaction of isocyanate and hydroxy groups. Specific examples thereof include, for example, 2 molecules per molecule described in JP-B-48-41708. A vinyl urethane compound containing two or more polymerizable vinyl groups in one molecule obtained by adding a vinyl monomer containing a hydroxy group represented by the following formula (M) to a polyisocyanate compound having one or more isocyanate groups Etc.
^{_{CH 2 = C (R M4)}} COOCH 2 CH (R M5) OH (M)
In formula (M), R ^M4 and R ^M5 each independently represent a hydrogen atom or a methyl group.

  Further, urethane acrylates described in JP-A-51-37193, JP-B-2-32293, JP-B-2-16765, JP-A-2003-344997, JP-A-2006-65210, Ethylene described in JP-B-58-49860, JP-B-56-17654, JP-B-62-39417, JP-B-62-39418, JP-A-2000-250211, and JP-A-2007-94138 Urethane compounds having an oxide-based skeleton, urethane compounds having hydrophilic groups described in US Pat. No. 7,153,632, JP-T 8-505958, JP-A 2007-293221, and JP-A 2007-293223 Are also suitable.

Details of the method of use such as the structure of the polymerizable compound, whether it is used alone or in combination, and the amount added can be arbitrarily set in consideration of the intended use of the final photosensitive layer or lithographic printing plate precursor.
The content of the polymerizable compound is preferably 5 to 75% by mass, more preferably 10 to 70% by mass, and particularly preferably 15 to 60% by mass with respect to the total solid content of the photosensitive layer.

[Component C: Binder polymer]
The photosensitive layer used in the present invention preferably further contains a binder polymer.
It does not specifically limit as a binder polymer which can be used for this invention, A well-known binder polymer can be used conveniently. Especially, as a binder polymer, an acrylic resin, polyvinyl acetal resin, and a polyurethane resin are preferable.

The binder polymer used in the photosensitive layer of the present invention is preferably a binder polymer used in an on-press development type lithographic printing plate precursor (hereinafter also referred to as on-press development binder polymer).
The binder polymer for on-press development is preferably a binder polymer having an alkylene oxide chain. The binder polymer having an alkylene oxide chain may have a poly (alkylene oxide) moiety in the main chain or in a side chain, and may be a graft polymer having a poly (alkylene oxide) in the side chain. It may be a block copolymer of a block composed of a poly (alkylene oxide) -containing repeating unit and a block composed of a (alkylene oxide) -free repeating unit.
A polyurethane resin is preferred when it has a poly (alkylene oxide) moiety in the main chain. As the main chain polymer in the case of having a poly (alkylene oxide) moiety in the side chain, (meth) acrylic resin, polyvinyl acetal resin, polyurethane resin, polyurea resin, polyimide resin, polyamide resin, epoxy resin, polystyrene resin, novolac type A phenol resin, a polyester resin, a synthetic rubber, and a natural rubber are exemplified, and a (meth) acrylic resin is particularly preferable.

The alkylene oxide is preferably an alkylene oxide having 2 to 6 carbon atoms, particularly preferably ethylene oxide or propylene oxide.
The number of repeating alkylene oxides at the poly (alkylene oxide) site is preferably 2-120, more preferably 2-70, and even more preferably 2-50.
If the number of alkylene oxide repeats is 120 or less, both the printing durability due to wear and the printing durability due to ink acceptance are not deteriorated.

  The poly (alkylene oxide) moiety is preferably contained in the structure represented by the following formula AO as the side chain of the binder, and contained in the structure represented by the following formula AO as the side chain of the (meth) acrylic resin. More preferably.

In formula AO, y represents 2 to 120, R ^AO1 represents a hydrogen atom or an alkyl group, and R ^AO2 represents a hydrogen atom or a monovalent organic group.
As the monovalent organic group, an alkyl group having 1 to 6 carbon atoms is preferable, and a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, or a tert-butyl group. Group, n-pentyl group, isopentyl group, neopentyl group, n-hexyl group, isohexyl group, 1,1-dimethylbutyl group, 2,2-dimethylbutyl group, cyclopentyl group and cyclohexyl group.
In the formula AO, y is preferably 2 to 70, and more preferably 2 to 50. R ^AO1 is preferably a hydrogen atom or a methyl group, and particularly preferably a hydrogen atom. R ^AO2 is particularly preferably a hydrogen atom or a methyl group.

The binder polymer may have crosslinkability in order to improve the film strength of the image area. In order to impart crosslinkability to the polymer, a crosslinkable functional group such as an ethylenically unsaturated bond may be introduced into the main chain or side chain of the polymer. The crosslinkable functional group may be introduced by copolymerization.
Examples of the polymer having an ethylenically unsaturated bond in the main chain of the molecule include poly-1,4-butadiene and poly-1,4-isoprene.
Examples of polymers having an ethylenically unsaturated bond in the side chain of the molecule are polymers of esters or amides of acrylic acid or methacrylic acid, wherein the ester or amide residue (R of -COOR or -CONHR) is Mention may be made of polymers having an ethylenically unsaturated bond.

Examples of the residue (the R) having an ethylenically unsaturated _{bond, - (CH 2) n CR} 1A = CR 2A R 3A, - (CH 2 O) n CH 2 CR 1A = CR 2A R 3A, - _{(CH 2 CH 2 O) n} CH 2 CR 1A = CR 2A R 3A, - (CH 2) n NH-CO-O-CH 2 CR 1A = CR 2A R 3A, - (CH 2) n -O-CO -CR ^1A = CR ^2A R ^3A and - (CH ₂ CH ₂ O) in ₂ -X (wherein, in each of R ^1A to R ^3A independently, a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, Represents an aryl group, an alkoxy group or an aryloxy group, and R ^1A and R ^2A or R ^3A may combine with each other to form a ring, n represents an integer of 1 to 10, and X represents dicyclo. Represents a pentadienyl residue).

Specific examples of the ester _{residue, -CH 2 CH = CH 2,} ( described in JP Kokoku _{7-21633.) - CH 2 CH 2} O-CH 2 CH = CH 2, -CH 2 C _{(CH 3) = CH 2,} -CH 2 CH = CH-C 6 H 5, -CH 2 CH 2 OCOCH = CH-C 6 H 5, -CH 2 CH 2 -NHCOO-CH 2 CH = CH 2 and - CH ₂ CH ₂ O—X (wherein X represents a dicyclopentadienyl residue).
Specific examples of the amide residue include —CH ₂ CH═CH ₂ , —CH ₂ CH ₂ —Y (wherein Y represents a cyclohexene residue), —CH ₂ CH ₂ —OCO—CH═CH _2. Is mentioned.

  In the binder having crosslinkability, for example, free radicals (polymerization initiating radicals or growth radicals in the polymerization process of the polymerizable compound) are added to the crosslinkable functional group, and directly between the polymers or via a polymerization chain of the polymerizable compound. Then, addition polymerization is performed, and a crosslink is formed between the polymer molecules to be cured. Alternatively, atoms in the polymer (eg, hydrogen atoms on carbon atoms adjacent to the functional bridging group) are abstracted by free radicals to form polymer radicals that are bonded together, thereby causing cross-linking between polymer molecules. Forms and cures.

  The content of the crosslinkable group in the binder polymer (content of unsaturated double bond capable of radical polymerization by iodometric titration) is preferably 0 per gram of the binder polymer from the viewpoint of good sensitivity and good storage stability. 0.1 to 10.0 mmol, more preferably 1.0 to 7.0 mmol, and particularly preferably 2.0 to 5.5 mmol.

  Specific examples 1 to 11 of the binder polymer for on-press development are shown below, but the present invention is not limited thereto. In the following exemplary compounds, a numerical value written together with each repeating unit (a numerical value written together with the main chain repeating unit) represents a mole percentage of the repeating unit. The numerical value written together with the repeating unit of the side chain indicates the number of repeating parts. Me represents a methyl group, and Et represents an ethyl group.

  The molecular weight of the binder polymer is preferably a mass average molar mass (Mw) of 2,000 or more, more preferably 5,000 or more, and 10,000 to 300,000 as a polystyrene-converted value by the GPC method. More preferably.

  In the present invention, if necessary, hydrophilic polymers such as polyacrylic acid and polyvinyl alcohol described in JP-A-2008-195018 can be used in combination. Further, a lipophilic polymer and a hydrophilic polymer can be used in combination.

  When applied to the photosensitive layer used in the present invention, the form of the binder polymer may be present in the photosensitive layer as a binder that serves as a linking function for each component, or may be present in the form of particles. . When present in the form of particles, the average primary particle size is preferably 10 to 1,000 nm, more preferably 20 to 300 nm, and particularly preferably 30 to 120 nm.

In the photosensitive layer used in the present invention, the binder polymer may be used alone or in combination of two or more.
The binder polymer can be contained in an arbitrary amount in the photosensitive layer used in the present invention, but the content of the binder polymer is 1 to 90 mass based on the total solid content of the photosensitive layer used in the present invention. %, And more preferably 5 to 80% by mass.

[Sensitizing dye]
The photosensitive layer used in the present invention preferably further contains a sensitizing dye. The sensitizing dye is particularly limited as long as it absorbs light at the time of image exposure to be in an excited state and supplies energy to the polymerization initiator by electron transfer, energy transfer or heat generation to improve the polymerization initiation function. It can be used without. In particular, a sensitizing dye having a maximum absorption in a wavelength range of 350 to 450 nm or 750 to 1,400 nm is preferably used.

  Examples of the sensitizing dye having the maximum absorption in the wavelength range of 350 to 450 nm include merocyanine dyes, benzopyrans, coumarins, aromatic ketones, and anthracenes.

  Among the sensitizing dyes having maximum absorption in the wavelength range of 350 nm to 450 nm, a dye more preferable from the viewpoint of high sensitivity is a dye represented by the following general formula (IX).

In the formula IX, A represents an aromatic ring group or a heterocyclic group which may have a substituent, and X represents an oxygen atom, a sulfur atom or N- (R ₃ ). R ₁ , R ₂ and R ₃ each independently represents a monovalent nonmetallic atomic group, and A and R ₁ or R ₂ and R ₃ are bonded to each other to form an aliphatic or aromatic ring. May be formed.

Formula IX will be described in more detail. R ₁ , R ₂ and R ₃ are each independently a monovalent nonmetallic atomic group, preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group. Represents a substituted or unsubstituted aromatic heterocyclic residue, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkylthio group, a hydroxy group, or a halogen atom.

Next, A in Formula IX will be described. A represents an aromatic ring group or a heterocyclic group which may have a substituent. Specific examples of the aromatic ring or heterocyclic ring which may have a substituent include R ₁ and R in the general formula IX. Examples thereof include the same as the substituted or unsubstituted aryl group and the substituted or unsubstituted aromatic heterocyclic residue described in ₂ and R ₃ .

  Specific examples of such a sensitizing dye include compounds described in paragraphs 0047 to 0053 of JP-A-2007-58170.

  Furthermore, a sensitizing dye represented by the following formula V or VI can also be used.

In Formula V, R ^{V1 to} R ^V14 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a cyano group, or a halogen atom. However, at least one of R ^{V1 to} R ^V10 represents an alkoxy group having 2 or more carbon atoms.
In Formula VI, R ^{V15 to} R ^V32 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a cyano group, or a halogen atom. However, at least one of R ^{V15 to} R ^V24 represents an alkoxy group having 2 or more carbon atoms.

  As specific examples of such a sensitizing dye, compounds described in European Patent Application Publication No. 1349006 and International Publication No. WO2005 / 029187 are preferably used.

  Also, JP 2007-171406 A, JP 2007-206216 A, JP 2007-206217 A, JP 2007-225701 A, JP 2007-225702 A, JP 2007-316582 A, Sensitizing dyes described in JP-A-2007-328243 can also be preferably used.

  Subsequently, a sensitizing dye having a maximum absorption in a wavelength range of 750 to 1,400 nm that is preferably used in the present invention (hereinafter sometimes referred to as “infrared absorber”) will be described in detail. As the infrared absorber, a dye or a pigment is preferably used.

As the dye, commercially available dyes and known dyes described in documents such as “Dye Handbook” (edited by the Society for Synthetic Organic Chemistry, published in 1970) can be used. Specifically, dyes such as azo dyes, metal complex azo dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinoneimine dyes, methine dyes, cyanine dyes, squarylium dyes, pyrylium salts, metal thiolate complexes, etc. Is mentioned.
Particularly preferred among these dyes are cyanine dyes, squarylium dyes, pyrylium salts, nickel thiolate complexes, and indolenine cyanine dyes. Further, cyanine dyes and indolenine cyanine dyes are preferred, and particularly preferred examples include cyanine dyes represented by the following general formula a.

In formula a, X ^a1 represents a hydrogen atom, a halogen atom, —NPh ₂ , —X ^a2 —L ^a1 or a group represented by formula a-2. Here, X ^a2 represents an oxygen atom, a nitrogen atom, or a sulfur atom, and L ^a1 represents an aromatic having a hydrocarbon group having 1 to 12 carbon atoms and a hetero atom (N, S, O, halogen atom, Se). An aromatic ring or a hydrocarbon group having 1 to 12 carbon atoms including a hetero atom, and ph represents a phenyl group;

In the formula _a-2, X a a ^- is Z _a a to be described later ^- has the same definition as, R ^a represents a hydrogen atom, an alkyl group, an aryl group, a substituted or unsubstituted amino group, and a halogen atom Represents a substituent, and * represents a bonding position with another bond.

R ^a1 and R ^a2 each independently represent a hydrocarbon group having 1 to 12 carbon atoms. In view of the storage stability of the photosensitive layer coating liquid described later, R ^a1 and R ^a2 are preferably hydrocarbon groups having 2 or more carbon atoms. R ^a1 and R ^a2 may be bonded to each other to form a ring, and when forming a ring, it is particularly preferable to form a 5-membered ring or a 6-membered ring.

Ar ^a1 and Ar ^a2 may be the same or different and each represents an aromatic hydrocarbon group which may have a substituent. Preferred aromatic hydrocarbon groups include a benzene ring and a naphthalene ring. Moreover, as a preferable substituent, a C12 or less hydrocarbon group, a halogen atom, and a C12 or less alkoxy group are mentioned. Y ^a1 and Y ^a2 may be the same or different and each represents a sulfur atom or a dialkylmethylene group having 12 or less carbon atoms. R ^a3 and R ^a4 may be the same or different and each represents a hydrocarbon group having 20 or less carbon atoms which may have a substituent. Preferred substituents include alkoxy groups having 12 or less carbon atoms, carboxy groups, and sulfo groups. R ^a5 , R ^a6 , R ^a7 and R ^a8 may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 12 or less carbon atoms. From the availability of raw materials, a hydrogen atom is preferred. Z _a a ⁻ represents a counter anion. However, when the cyanine dye represented by the formula a has an anionic substituent in the structure thereof, Z _a a is does not require charge neutralization ^- is not necessary. Preferred Z _a a ^- from the viewpoint of storage stability of the photosensitive layer coating liquid, a halogen ion, perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion, and sulfonate ion, particularly preferably a perchlorate Ions, hexafluorophosphate ions, and aryl sulfonate ions.

  Specific examples of the cyanine dye represented by the formula a that can be suitably used include those described in paragraphs 0017 to 0019 of JP-A No. 2001-133969.

  Further, other particularly preferable examples include specific indolenine cyanine dyes described in JP-A-2002-278057.

  Examples of pigments include commercially available pigment and color index (CI) manuals, “Latest Pigment Handbook” (edited by the Japan Pigment Technology Association, published in 1977), “Latest Pigment Applied Technology” (published by CMC, published in 1986), “Printing” The pigments described in "Ink Technology", published by CMC Publishing, 1984) can be used.

In addition, as the sensitizing dye of the photosensitive layer used in the present invention, compounds described as Component D: sensitizing dye contained in an intermediate layer described later can also be suitably used.
From the viewpoint of stain resistance and plate inspection properties of the resulting lithographic printing plate, it is preferable to use Component D: sensitizing dye contained in the intermediate layer described later, and more preferably a compound represented by Formula 1 described later. preferable.

In the photosensitive layer used in the invention, a sensitizing dye may be used alone or in combination of two or more.
The sensitizing dye can be contained in an arbitrary amount in the photosensitive layer used in the present invention. The content of the sensitizing dye is 0. 0% relative to the total solid content of the photosensitive layer used in the present invention. It is preferable that it is 05-30 mass%, It is more preferable that it is 0.1-20 mass%, It is still more preferable that it is 0.2-10 mass%.

[Reducing agent]
The photosensitive layer used in the present invention preferably contains a reducing agent described below from the viewpoint of improving printing durability in a lithographic printing plate, and examples thereof include the following five types.
(I) Alkyl or aryl art complex: It is considered that an active radical is generated by oxidative cleavage of a carbon-hetero bond. Specifically, a borate salt compound is preferably used.
Examples of the borate salt compound include JP-A-62-143044, JP-A-62-1050242, JP-A-9-188585, JP-A-9-188686, JP-A-9-188710, JP-A-2000-131837. , JP 2002-107916, Japanese Patent No. 2764769, JP 2002-116539, etc., and Kunz, Martin “Rad Tech '98. Proceeding April 19-22, 1998, Chicago”. Organoborates are preferred.
(Ii) N-arylalkylamine compound: It is considered that a C—X bond on carbon adjacent to nitrogen is cleaved by oxidation to generate an active radical. X is preferably a hydrogen atom, a carboxy group, a trimethylsilyl group or a benzyl group. Specifically, for example, N-phenylglycines described in the following chemical formula (the phenyl group may or may not have a substituent), N-phenyliminodiacetic acid (the phenyl group has a substituent). Or not).

（iii）含硫黄化合物：上述のアミン類の窒素原子を硫黄原子に置き換えたものが、同様の作用により活性ラジカルを生成し得る。例えばフェニルチオ酢酸（フェニル基に置換基を有していてもいなくてもよい。）が挙げられる。
（iv）含錫化合物:上述のアミン類の窒素原子を錫原子に置き換えたものが、同様の作用により活性ラジカルを生成し得る。
（v）スルフィン酸塩類：酸化により活性ラジカルを生成し得る。具体的は、アリールスルフィン駿ナトリウム等を挙げることができる。
還元剤は、１種のみを添加しても、２種以上を併用してもよい。
還元剤の含有量としては、感光層の全固形分に対し、０．０１〜３０質量％であることが好ましく、０．０５〜２５質量％であることが更に好ましく、０．１〜２０質量％であることが更に好ましい。

(Iii) Sulfur-containing compounds: those in which the nitrogen atom of the above-described amines is replaced with a sulfur atom can generate active radicals by the same action. Examples thereof include phenylthioacetic acid (the phenyl group may or may not have a substituent).
(Iv) Tin-containing compound: A compound in which the nitrogen atom of the above-described amines is replaced with a tin atom can generate an active radical by the same action.
(V) Sulfinic acid salts: Active radicals can be generated by oxidation. Specific examples include arylsulfin sodium.
A reducing agent may add only 1 type or may use 2 or more types together.
As content of a reducing agent, it is preferable that it is 0.01-30 mass% with respect to the total solid of a photosensitive layer, It is still more preferable that it is 0.05-25 mass%, 0.1-20 mass % Is more preferable.

  Although the preferable example of a reducing agent is described below, this invention is not limited to this. In the following exemplified compounds, Me represents a methyl group, Et represents an ethyl group, and n-Bu represents an n-butyl group.

[Polymer particles]
From the viewpoint of improving the on-press developability of the lithographic printing plate precursor, the photosensitive layer may contain polymer particles. The polymer particles in the present invention are preferably polymer particles that can convert the photosensitive layer to hydrophobic when heat is applied. The polymer particles are at least one selected from hydrophobic thermoplastic polymer particles, heat-reactive polymer particles, polymer particles having a polymerizable group, microcapsules containing a hydrophobic compound, and microgel (crosslinked polymer particles). It is preferable that Among these, polymer particles having a polymerizable group and microgel are preferable.

Examples of the hydrophobic thermoplastic polymer particles used in the present invention include Research Disclosure No. 1 of January 1992. 33303, hydrophobic thermoplastic polymer particles described in JP-A-9-123387, JP-A-9-131850, JP-A-9-171249, JP-A-9-171250 and European Patent No. 931647 are suitable. It is mentioned in.
Specific examples of the polymer constituting the hydrophobic thermoplastic polymer particles include ethylene, styrene, vinyl chloride, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, vinylidene chloride, acrylonitrile, vinyl carbazole, polyalkylene structure And homopolymers or copolymers of monomers such as acrylates or methacrylates, or mixtures thereof. Preferably, polystyrene, a copolymer containing styrene and acrylonitrile, and polymethyl methacrylate are used. The average particle size of the hydrophobic thermoplastic polymer particles is preferably 0.01 to 2.0 μm.

  Examples of the thermally reactive polymer particles used in the present invention include polymer fine particles having a thermally reactive group. The polymer particles having a thermoreactive group form a hydrophobized region by crosslinking by a thermal reaction and a functional group change at that time.

  The thermoreactive group in the polymer particles having a thermoreactive group may be any functional group that performs any reaction as long as a chemical bond is formed, but is preferably a polymerizable group. , Ethylenically unsaturated groups that undergo radical polymerization reactions (for example, acryloyl group, methacryloyl group, vinyl group, allyl group, etc.), cationic polymerizable groups (for example, vinyl group, vinyloxy group, epoxy group, oxetanyl group, etc.), addition Isocyanato group that performs the reaction or a block thereof, epoxy group, vinyloxy group, and functional group having an active hydrogen atom that is a reaction partner thereof (for example, amino group, hydroxy group, carboxy group, etc.), carboxy group that performs a condensation reaction, and Hydroxy group or amino group as reaction partner, acid anhydride for ring-opening addition reaction, and amino as reaction partner Or such hydroxy group are preferably exemplified.

  As the microcapsules used in the present invention, for example, as described in JP-A Nos. 2001-277740 and 2001-277742, all or part of the constituent components of the photosensitive layer are encapsulated in microcapsules. Is mentioned. The constituent components of the photosensitive layer can also be contained outside the microcapsules. The photosensitive layer containing microcapsules is preferably a mode in which hydrophobic constituent components are encapsulated in microcapsules and hydrophilic constituent components are contained outside the microcapsules.

  In the present invention, an embodiment containing crosslinked polymer particles, that is, a microgel is also used. The microgel may contain a part of the constituent components of the photosensitive layer in at least one of the inside and the surface thereof. In particular, the mode of forming the reactive microgel by having a radical polymerizable group on the surface is an image forming sensitivity. And from the viewpoint of printing durability.

As a method for microencapsulating or microgelling the constituent components of the photosensitive layer, known methods can be used.
The average particle size of the microcapsules or microgel is preferably 0.01 to 3.0 μm, more preferably 0.05 to 2.0 μm, and particularly preferably 0.10 to 1.0 μm. Within this range, good resolution and stability over time can be obtained.
The content of the hydrophobizing precursor is preferably 5 to 90% by mass of the total solid content of the photosensitive layer.

[Other ingredients]
The photosensitive layer used in the present invention may further contain other components as necessary. The other components are not particularly limited, and known additives that are usually used in the photosensitive layer can be used, and examples thereof include a low molecular weight hydrophilic compound and a sensitizer described below.

(1) Low molecular weight hydrophilic compound The photosensitive layer in the invention may contain a low molecular weight hydrophilic compound in order to improve the on-press developability without reducing the printing durability. The low molecular weight hydrophilic compound is preferably a compound having a molecular weight of less than 1,000, more preferably a compound having a molecular weight of less than 800, and still more preferably a compound having a molecular weight of less than 500.
As the low molecular weight hydrophilic compound, for example, as the water-soluble organic compound, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol and the like glycols and ether or ester derivatives thereof, glycerin, Polyols such as pentaerythritol and tris (2-hydroxyethyl) isocyanurate, organic amines such as triethanolamine, diethanolamine and monoethanolamine and salts thereof, organic sulfones such as alkylsulfonic acid, toluenesulfonic acid and benzenesulfonic acid Acids and salts thereof, organic sulfamic acids such as alkylsulfamic acid and salts thereof, organic sulfuric acids such as alkylsulfuric acid and alkylethersulfuric acid and salts thereof, phenylphosphonic acid Organic phosphonic acids and salts thereof, tartaric acid, oxalic acid, citric acid, malic acid, lactic acid, gluconic acid, organic carboxylic acids and salts thereof such as amino acids, betaines, and the like.

  In the present invention, it is preferable to contain at least one selected from polyols, organic sulfates, organic sulfonates and betaines.

  Specific examples of organic sulfonates include alkyl sulfonates such as sodium n-butyl sulfonate, sodium n-hexyl sulfonate, sodium 2-ethylhexyl sulfonate, sodium cyclohexyl sulfonate, sodium n-octyl sulfonate; 5 , 8,11-Trioxapentadecane-1-sulfonic acid sodium salt, 5,8,11-trioxaheptadecane-1-sulfonic acid sodium salt, 13-ethyl-5,8,11-trioxaheptadecane-1-sulfone Alkyl sulfonates containing ethylene oxide chains such as sodium acid, sodium 5,8,11,14-tetraoxatetracosane-1-sulfonate; sodium benzenesulfonate, sodium p-toluenesulfonate, p-hydroxybenzenesulfonic acid Nat , Sodium p-styrenesulfonate, dimethyl-5-sulfonate sodium isophthalate, sodium 1-naphthylsulfonate, sodium 4-hydroxynaphthylsulfonate, disodium 1,5-naphthalenedisulfonate, 1,3,6- Examples thereof include aryl sulfonates such as trisodium naphthalene trisulfonate, compounds described in paragraphs 0026 to 0031 of JP-A-2007-276454 and paragraphs 0020 to 0047 of JP-A-2009-154525. The salt may be a potassium salt or a lithium salt.

  Examples of organic sulfates include sulfates of alkyl, alkenyl, alkynyl, aryl or heterocyclic monoethers of polyethylene oxide. The number of ethylene oxide units is preferably 1 to 4, and the salt is preferably a sodium salt, potassium salt or lithium salt. Specific examples thereof include compounds described in paragraphs 0034 to 0038 of JP-A-2007-276454.

  As the betaines, compounds having 1 to 5 carbon atoms of the hydrocarbon substituent on the nitrogen atom are preferable, and specific examples thereof include trimethylammonium acetate, dimethylpropylammonium acetate, 3-hydroxy-4-trimethylammonium. Obtylate, 4- (1-pyridinio) butyrate, 1-hydroxyethyl-1-imidazolioacetate, trimethylammonium methanesulfonate, dimethylpropylammonium methanesulfonate, 3-trimethylammonio-1-propanesulfonate, 3 -(1-pyridinio) -1-propanesulfonate and the like.

  Since the low molecular weight hydrophilic compound has a small hydrophobic portion structure and almost no surface-active action, the fountain solution penetrates into the exposed portion (image portion) of the photosensitive layer and decreases the hydrophobicity and film strength of the image portion. The ink acceptability and printing durability of the photosensitive layer can be maintained well.

The amount of the low molecular weight hydrophilic compound added to the photosensitive layer is preferably 0.5 to 20% by mass, more preferably 1 to 15% by mass, and still more preferably 2 to 10% by mass based on the total solid content of the photosensitive layer. In this range, good on-press developability and printing durability can be obtained.
A low molecular weight hydrophilic compound may be used individually by 1 type, and 2 or more types may be mixed and used for it.

(2) Grease-sensitizing agent A grease-sensitizing agent such as a phosphonium compound, a nitrogen-containing low-molecular compound, or an ammonium group-containing polymer can be used in the photosensitive layer in order to improve the inking property. In particular, when an inorganic layered compound is contained in the protective layer, these compounds function as a surface coating agent for the inorganic layered compound, and prevent a decrease in the inking property during printing by the inorganic layered compound.
Among these, as the sensitizer, it is preferable to use a phosphonium compound, a nitrogen-containing low molecular weight compound, and an ammonium group-containing polymer in combination, and a phosphonium compound, a quaternary ammonium salt, and an ammonium group-containing polymer are used in combination. It is more preferable.

  Preferable phosphonium compounds include phosphonium compounds described in JP-A-2006-297907 and JP-A-2007-50660. Specific examples include tetrabutylphosphonium iodide, butyltriphenylphosphonium bromide, tetraphenylphosphonium bromide, 1,4-bis (triphenylphosphonio) butanedi (hexafluorophosphate), 1,7-bis (tri Phenylphosphonio) heptane sulfate, 1,9-bis (triphenylphosphonio) nonane = naphthalene-2,7-disulfonate, and the like.

  Examples of nitrogen-containing low molecular weight compounds include amine salts and quaternary ammonium salts. Also included are imidazolinium salts, benzoimidazolinium salts, pyridinium salts, and quinolinium salts. Of these, quaternary ammonium salts and pyridinium salts are preferred. Specific examples include tetramethylammonium = hexafluorophosphate, tetrabutylammonium = hexafluorophosphate, dodecyltrimethylammonium = p-toluenesulfonate, benzyltriethylammonium = hexafluorophosphate, benzyldimethyloctylammonium = hexafluorophosphate. And the compounds described in paragraphs 0021 to 0037 of JP2008-284858A, paragraphs 0030 to 0057 of JP2009-90645A, and the like.

  The ammonium group-containing polymer may be any polymer as long as it has an ammonium group in its structure, but a polymer containing 5 to 80 mol% of (meth) acrylate having an ammonium group in the side chain as a copolymerization component is preferable. Specific examples include the polymers described in paragraphs 0089 to 0105 of JP2009-208458A.

  The ammonium group-containing polymer preferably has a reduced specific viscosity (unit: ml / g) determined by the measurement method described in JP-A-2009-208458, in the range of 5 to 120, and in the range of 10 to 110. More preferred are those in the range of 15-100. When the reduced specific viscosity is converted into a mass average molar mass (Mw), it is preferably 10,000 to 150,000, more preferably 17,000 to 140,000, and particularly preferably 20,000 to 130,000.

Specific examples of the ammonium group-containing polymer are shown below.
(1) 2- (Trimethylammonio) ethyl methacrylate = p-toluenesulfonate / 3,6-dioxaheptyl methacrylate copolymer (molar ratio 10/90, Mw 45,000)
(2) 2- (Trimethylammonio) ethyl methacrylate = hexafluorophosphate / 3,6-dioxaheptyl methacrylate copolymer (molar ratio 20/80, Mw 60,000)
(3) 2- (Ethyldimethylammonio) ethyl methacrylate = p-toluenesulfonate / hexyl methacrylate copolymer (molar ratio 30/70, Mw 45,000)
(4) 2- (Trimethylammonio) ethyl methacrylate = hexafluorophosphate / 2-ethylhexyl methacrylate copolymer (molar ratio 20/80, Mw 60,000)
(5) 2- (Trimethylammonio) ethyl methacrylate = methyl sulfate / hexyl methacrylate copolymer (molar ratio 40/60, Mw 7 million)
(6) 2- (Butyldimethylammonio) ethyl methacrylate = hexafluorophosphate / 3,6-dioxaheptyl methacrylate copolymer (molar ratio 25/75, Mw 650,000)
(7) 2- (Butyldimethylammonio) ethyl acrylate = hexafluorophosphate / 3,6-dioxaheptyl methacrylate copolymer (molar ratio 20/80, Mw 650,000)
(8) 2- (butyldimethylammonio) ethyl methacrylate = 13-ethyl-5,8,11-trioxa-1-heptadecanesulfonate / 3,6-dioxaheptyl methacrylate copolymer (molar ratio 20/80 , Mw75,000)
(9) 2- (butyldimethylammonio) ethyl methacrylate = hexafluorophosphate / 3,6-dioxaheptyl methacrylate / 2-hydroxy-3-methacryloyloxypropyl methacrylate copolymer (molar ratio 15/80/5 , Mw 650,000)

  The content of the sensitizer is preferably 0.01 to 30.0% by mass, more preferably 0.1 to 15.0% by mass, and more preferably 1 to 10% by mass with respect to the total solid content of the photosensitive layer. Further preferred.

(3) Others Further, in the photosensitive layer, as other components, surfactants, colorants, print-out agents, polymerization inhibitors, higher fatty acid derivatives, plasticizers, inorganic particles, inorganic layered compounds, co-sensitizers and A chain transfer agent or the like can be added. Specifically, compounds and additions described in paragraphs 0114 to 0159 of JP2008-284817A, paragraphs 0023 to 0027 of JP2006-091479A, paragraph 0060 of U.S. Patent Publication No. 2008/0311520. An amount is preferably used.

[Formation of photosensitive layer]
The photosensitive layer in the lithographic printing plate precursor according to the invention is, for example, as described in paragraphs 0142 to 0143 of JP-A-2008-195018, wherein the necessary components described above are dispersed or dissolved in a solvent described later and used for the photosensitive layer. It can be formed by preparing a coating solution, applying the coating solution on a support by a known method such as bar coater coating, and drying. The coating amount (solid content) of the photosensitive layer on the support obtained after coating and drying varies depending on the application, but is preferably 0.3 to 3.0 g / m ² . Within this range, good sensitivity and good film properties of the photosensitive layer can be obtained.

  As the solvent used when preparing the coating solution for the photosensitive layer, a known solvent can be used. Specifically, water, acetone, methyl ethyl ketone (2-butanone), cyclohexane, ethyl acetate, ethylene dichloride, tetrahydrofuran, toluene, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, propylene glycol monomethyl ether, propylene glycol Monoethyl ether, acetylacetone, cyclohexanone, diacetone alcohol, ethylene glycol monomethyl ether acetate, ethylene glycol ethyl ether acetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether acetate, 1-methoxy-2-propanol, 3-methoxy- 1-propanol, methoxymethoxyethanol , Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, 3-methoxypropyl acetate, N, N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, Examples include methyl lactate and ethyl lactate. These solvents can be used singly or in combination of two or more. In addition, it is preferable that the solid content density | concentration in the coating liquid for photosensitive layers is 1-50 mass%. In addition, solid content concentration is a density | concentration of all the components except a solvent.

<Intermediate layer>
The intermediate layer used in the present invention contains, as component D, a sensitizing dye and, as component E, a polymer having a repeating unit having a structure that interacts with the surface of the aluminum support.
The intermediate layer used in the present invention preferably contains 0.1 to 60% by mass of component D and 5 to 80% by mass of component E based on the total solid content of the intermediate layer.
Moreover, it is preferable that the intermediate | middle layer used for this invention contains a polymerization initiator and another component as needed.

[Component D: Sensitizing dye]
The intermediate layer used in the present invention contains a sensitizing dye as component D.
Component D used in the present invention is not particularly limited, and a known compound can be used, but a compound represented by the following formula 1 is preferable.

In Formula 1, X ¹ represents a hydrogen atom, a halogen atom, or a group represented by Formulas 2 to 6 below, Za represents a counter ion that neutralizes the charge, and R ¹ and R ² each independently represents the number of carbon atoms. 1 to 12 represents a hydrocarbon group, Ar ¹ and Ar ² represent an aromatic ring-forming group, Y ¹ and Y ² each independently represents a sulfur atom or a C 1-12 dialkylmethylene group. R ³ and R ⁴ each independently represents a hydrocarbon group having 1 to 20 carbon atoms, and R ^{5 to} R ⁸ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms.

式２〜式６中、Ｌ¹〜Ｌ⁴はそれぞれ独立に、カルボニル基、スルホニル基、又は、−Ｎ（Ｒ^N）−、＝Ｎ−、−Ｓ−、又は、−Ｏ−を含んでもよい炭素原子数１〜２０の炭化水素基を表し、Ｒ^Nは水素原子、アルキル基又はアリール基を表し、Ｒａはアルキル基、アリール基、アミノ基、又は、ハロゲン原子を表し、ｎ１は０〜５の整数を表し、Ｚｂは電荷を中和する対イオンを表し、●は他の構造との結合部位を表す。

In formula 2 to formula 6, L ^{1 to} L ⁴ may each independently contain a carbonyl group, a sulfonyl group, or —N (R ^N ) —, ═N—, —S—, or —O—. represents a hydrocarbon group having a carbon number of 1 to 20, R ^N represents a hydrogen atom, an alkyl group or an aryl group, Ra represents an alkyl group, an aryl group, an amino group, or a halogen atom, n1 is 0 to 5 Zb represents a counter ion that neutralizes the charge, and ● represents a binding site with another structure.

X ¹ represents a hydrogen atom, a halogen atom, or a group represented by Formulas 2 to 6, and is a hydrogen atom, a halogen atom, a group represented by Formula 2, Formula 3, Formula 4, or Formula 6. Preferably, it is more preferably a group represented by a halogen atom, Formula 2, Formula 3, or Formula 4, more preferably a group represented by Formula 3 or Formula 4, and represented by Formula 3. It is particularly preferably a group, and most preferably a group represented by the following formula 8.
Moreover, when using component D whose X < ¹ > is group represented by Formula 2, Formula 4, Formula 5, or Formula 6, from a printing durability viewpoint, an intermediate | middle layer contains the polymerization initiator mentioned later. It is preferable.

In Formula 2 to Formula 5, L ^{1 to} L ⁴ may each independently contain a carbonyl group, a sulfonyl group, or —N (R ^N ) —, ═N—, —S—, or —O—. Represents a hydrocarbon group having 1 to 20 carbon atoms. The hydrocarbon group includes both an aliphatic hydrocarbon group and an aromatic hydrocarbon group, and each may be linear, branched, or cyclic.
R ^N represents a hydrogen atom, an alkyl group or an aryl group, R ^N represents a hydrogen atom, an alkyl group or an aryl group is preferably an alkyl group.

In Formula 2, L ¹ is preferably an alkyl group, an aryl group, or a group represented by the following Formula 2-1, and is an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 12 carbon atoms. More preferably, it is more preferably an alkyl group having 1 to 8 carbon atoms or a phenyl group.
The alkyl group in L ¹ may have a substituent, and preferred substituents include an aryl group having 6 to 12 carbon atoms and a halogen atom.
The phenyl group in L ¹ may have a substituent, and preferred substituents include an alkyl group having 1 to 10 carbon atoms and a halogen atom.

  Although the preferable example of group represented by Formula 2 is given to the following, this invention is not limited to this.

In formula 3, L ² is preferably a group represented by any of the following formulas 3-1 to 3-6, and is a group represented by any of the formulas 3-1 to 3-3. More preferably, it is more preferably a group represented by Formula 3-3.

In Formula 3-1 to Formula 3-6, ● represents a bonding site with the O atom in Formula 3, and R ³⁰ is independently a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, —OR ³⁴ , It represents -NR ³⁵ R ³⁶ or -SR ^37, are each R ³¹ independently represents a hydrogen atom, an alkyl group or an aryl group, R ³² is an aryl ^{group, -OR 34, -NR 35 R 36} , -SR 37, —C (═O) R ³⁸ , —OC (═O) R ³⁸ or a halogen atom, R ³³ represents an aryl group, an alkenyl group, an alkoxy group or an onium group, and R ^{34 to} R ³⁷ are each independently A hydrogen atom, an alkyl group or an aryl group is represented, and each R ³⁸ independently represents an alkyl group, an aryl group, —OR ³⁴ , —NR ³⁵ R ³⁶ or —SR ³⁷ .

When R ³⁰ , R ³¹ and R ^{34 to} R ³⁸ are alkyl groups, alkyl groups having 1 to 30 carbon atoms are preferable, alkyl groups having 1 to 15 carbon atoms are more preferable, and alkyl groups having 1 to 10 carbon atoms are Further preferred. The alkyl group may be linear, branched or have a ring structure.
The carbon number of the alkenyl group in R ³⁰ and R ³³ is preferably 1-30, more preferably 1-15, and still more preferably 1-10.
When R ^{30 to} R ³⁸ are an aryl group, an aryl group having 6 to 30 carbon atoms is preferable, an aryl group having 6 to 20 carbon atoms is more preferable, and an aryl group having 6 to 12 carbon atoms is still more preferable.
The aryl group may have a substituent. Examples of substituents include alkyl groups, alkoxy groups, aryloxy groups, amino groups, alkylthio groups, arylthio groups, halogen atoms, carboxy groups, carboxylate groups, sulfo groups, sulfonate groups, alkyloxycarbonyl groups, aryloxycarbonyl groups. And a combination of these.

From the viewpoint of coloring property, R ³⁰ in Formula 3-1 is preferably an alkyl group, an alkenyl group, an aryl group, —OR ³⁴ , —NR ³⁵ R ³⁶ or —SR ³⁷ , and an alkyl group, —OR ³⁴ , It is more preferably —NR ³⁵ R ³⁶ or —SR ³⁷ , still more preferably an alkyl group or —OR ³⁴ , and particularly preferably —OR ³⁴ .
When R ³⁰ in Formula 3-1 is an alkyl group, the alkyl group is preferably an alkyl group having an arylthio group or an alkyloxycarbonyl group at the α-position.
When R ³⁰ in Formula 3-1 is —OR ³⁴ , R ³⁴ is preferably an alkyl group, more preferably an alkyl group having 1 to 8 carbon atoms, and an isopropyl group or a t-butyl group. More preferably, it is particularly preferably a t-butyl group.

From the viewpoint of color developability, R ³¹ in Formula 3-2 is preferably a hydrogen atom.
From the viewpoint of color developability, R ³² in Formula 3-2 is preferably —C (═O) OR ³⁴ , —OC (═O) OR ³⁴ or a halogen atom, and —C (═O) OR. More preferably, it is ³⁴ or —OC (═O) OR ³⁴ . When R ³² in Formula 3-2 is —C (═O) OR ³⁴ or —OC (═O) OR ³⁴ , R ³⁴ is preferably an alkyl group.

From the viewpoint of color development, each R ³¹ in formula 3-3 is preferably independently a hydrogen atom or an alkyl group, and more preferably at least one R ³¹ in formula 3-3 is an alkyl group. preferable.
Further, the alkyl group in R ³¹ is preferably an alkyl group having 1 to 10 carbon atoms, and more preferably an alkyl group having 3 to 10 carbon atoms.
Furthermore, the alkyl group in R ³¹ is preferably a branched alkyl group, more preferably a secondary or tertiary alkyl group, an isopropyl group, a cyclopentyl group, a cyclohexyl group, or t-butyl. More preferably, it is a group.
From the viewpoint of color development, R ³³ in Formula 3-3 is preferably an aryl group, an alkoxy group or an onium group, more preferably a p-dimethylaminophenyl group or a pyridinium group, and a pyridinium group. More preferably it is.
Examples of the onium group for R ³³ include a pyridinium group, an ammonium group, and a sulfonium group. The onium group may have a substituent. Examples of the substituent include alkyl groups, alkoxy groups, aryloxy groups, amino groups, alkylthio groups, arylthio groups, halogen atoms, carboxy groups, sulfo groups, alkyloxycarbonyl groups, aryloxycarbonyl groups, and combinations of these. However, an alkyl group, an aryl group, or a group obtained by combining these is preferable.
Among them, a pyridinium group is preferable, and an N-sulfoalkylpyridinium group, an N-carboxyalkylpyridinium group, an N-alkylpyridinium group, an N-benzylpyridinium group, an N- (alkoxypolyalkyleneoxyalkyl) pyridinium group, and an N-alkoxycarbonylmethyl. A pyridinium group or an N-alkyl-3,5-dimethyl-4-pyridinium group is more preferable, an N-sulfoalkylpyridinium group, an N-carboxyalkylpyridinium group, and an N-alkylpyridinium group are more preferable, and N-sulfobutyl- A 4-pyridinium group, an N-carboxypropyl-4-pyridinium group, and an N-methyl-4-pyridinium group are particularly preferable.
When R ³³ is a pyridinium group, examples of the counter anion include sulfonate ion, carboxylate ion, hexafluorophosphate ion, p-toluenesulfonate ion, perchlorate ion, and the like. P-toluenesulfonate ion, Hexafluorophosphate ions are preferred.

From the viewpoint of color development, R ³⁰ in Formula 3-4 is preferably an alkyl group or an aryl group, and more preferably one of the two R ³⁰ is an alkyl group and the other is an aryl group.
From the viewpoint of color development, R ³⁰ in Formula 3-5 is preferably an alkyl group or an aryl group, more preferably an aryl group, and still more preferably a p-methylphenyl group.
From the viewpoint of color developability, R ³⁰ in formula 3-6 is preferably independently an alkyl group or an aryl group, and more preferably a methyl group or a phenyl group.

  Moreover, it is preferable that the group represented by Formula 3 is a group represented by the following Formula 8.

In Formula 8, R ⁹ and R ¹⁰ each independently represent a hydrogen atom, an alkyl group or an aryl group, X ² represents an onium group, and ● represents a bonding site with another structure.

The R ⁹ and R ¹⁰ are each independently a hydrogen atom, an alkyl group or an aryl group, it is preferable that at least one of R ⁹ and R ¹⁰ is an alkyl group, one of R ⁹ and R ¹⁰ is an alkyl group More preferably, the other is a hydrogen atom.
The alkyl group in R ⁹ and R ¹⁰ is preferably an alkyl group having 1 to 10 carbon atoms, and more preferably an alkyl group having 3 to 10 carbon atoms.
Furthermore, the alkyl group in R ⁹ and R ¹⁰ is preferably a branched alkyl group, more preferably a secondary or tertiary alkyl group, an isopropyl group, a cyclopentyl group, a cyclohexyl group, or It is more preferably a t-butyl group, and particularly preferably an isopropyl group or a t-butyl group.
X ² represents an onium group, and examples thereof include a pyridinium group, an ammonium group, and a sulfonium group. The onium group may have a substituent. Examples of the substituent include alkyl groups, alkoxy groups, aryloxy groups, halogen atoms, carboxy groups, sulfo groups, alkyloxycarbonyl groups, aryloxycarbonyl groups, and combinations thereof. A group and a combination thereof are preferable.
Of the onium groups in X ² , a pyridinium group is preferable, and an N-sulfoalkylpyridinium group, an N-carboxyalkylpyridinium group, an N-alkylpyridinium group, an N-benzylpyridinium group, and an N- (alkoxypolyalkyleneoxyalkyl) pyridinium group. N-alkoxycarbonylmethylpyridinium group or N-alkyl-3,5-dimethyl-4-pyridinium group is more preferable, and N-sulfoalkylpyridinium group, N-carboxyalkylpyridinium group, and N-alkylpyridinium group are more preferable. N-sulfobutyl-4-pyridinium group, N-carboxypropyl-4-pyridinium group and N-methyl-4-pyridinium group are particularly preferable.
When X ² is a pyridinium group, examples of the counter anion include sulfonate ion, carboxylate ion, hexafluorophosphate ion, p-toluenesulfonate ion, perchlorate ion, and the like. P-toluenesulfonate ion, Hexafluorophosphate ions are preferred.
X ² is preferably a group represented by the following formula 9.

式９中、Ｒ¹¹はそれぞれ独立に、ハロゲン原子、アルキル基、アリール基、ヒドロキシ基、又は、アルコキシ基、を表し、複数のＲ¹¹が連結して環を形成してもよく、ｎ２は０〜４の整数を表し、Ｒ¹²はアルキル基又はアリール基を表し、Ｚｃは電荷を中和する対イオンを表し、●は他の構造との結合部位を表す。

In Formula 9, each R ¹¹ independently represents a halogen atom, an alkyl group, an aryl group, a hydroxy group, or an alkoxy group, and a plurality of R ¹¹ may be linked to form a ring, and n2 is 0 Represents an integer of ˜4, R ¹² represents an alkyl group or an aryl group, Zc represents a counter ion that neutralizes charge, and ● represents a binding site with another structure.

R ¹¹ each independently represents a halogen atom, an alkyl group, an aryl group, a hydroxy group, or an alkoxy group, and represents an F atom, a Cl atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 12 carbon atoms. , A hydroxy group, or an alkoxy group having 1 to 10 carbon atoms, and preferably an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, or a combination thereof.
A plurality of R ¹¹ may be linked to form a ring, and preferred examples of the ring include a benzene ring.
n2 represents an integer of 0 to 4, an integer of 0 to 2 is preferable, and 0 is more preferable.
R ¹² represents an alkyl group or an aryl group, preferably an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 12 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms.
The alkyl group preferably has a carboxylate group or a sulfonate group, and preferably has a sulfonate group at the terminal. When the alkyl group has a carboxylate group or a sulfonate group, Zc may not be present.
Zc represents a counter ion that neutralizes the charge, and has the same meaning as Za described later, and the preferred embodiment is also the same.

Although the preferable example of group represented by Formula 3 is given to the following, this invention is not limited to this. TsO ⁻ represents a tosylate anion.

In Formula 4, each L ³ is preferably independently an alkyl group, an aryl group, an alkoxycarbonyl group, or an alkylsulfonyl group, and an alkyl group having 1 to 10 carbon atoms, a phenyl group, or 1 to 10 carbon atoms. Are more preferably an alkoxysulfonyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms, a phenyl group, and an alkoxycarbonyl group having 1 to 4 carbon atoms. , A methyl group, a phenyl group, or a t-butoxycarbonyl group is more preferable, and it is particularly preferable that two L ^3s are both phenyl groups.

  Although the preferable example of group represented by Formula 4 below is given, this invention is not limited to this.

In Formula 5, L ⁴ is preferably an alkyl group or an aryl group, more preferably an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 12 carbon atoms, and further a phenyl group. preferable.

  Although the preferable example of group represented by Formula 5 below is given, this invention is not limited to this.

In Formula 6, ^RN represents a hydrogen atom, an alkyl group, or an aryl group, and is preferably an alkyl group.
Ra represents an alkyl group, an aryl group, an amino group, or a halogen atom, and is an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, an amino group, an F atom, or a Cl atom. An alkyl group having 1 to 4 carbon atoms or a phenyl group is more preferable.
n1 represents an integer of 0 to 5, is preferably 0 or 1, and more preferably 0.
Zb represents a counter ion that neutralizes the charge, and has the same meaning as Za described later, and the preferred embodiment is also the same.

  Although the preferable example of group represented by Formula 6 below is given, this invention is not limited to this.

It describes preferred examples of X ¹ are shown below, but the invention is not limited thereto. In the following examples, ● represents a binding site with another structure.

In formula 1, Za represents a counter ion that neutralizes the charge. When an anionic species is indicated, sulfonate ion, carboxylate ion, hexafluorophosphate ion, p-toluenesulfonate ion, perchlorate ion, etc. may be mentioned. Hexafluorophosphate ions are particularly preferred. In the case of indicating a cationic species, alkali metal ions, alkaline earth metal ions, ammonium ions, pyridinium ions or sulfonium ions are preferable, sodium ions, potassium ions, ammonium ions, pyridinium ions or sulfonium ions are more preferable, sodium ions, potassium ions More preferred are ions or ammonium ions.
R ^{1 to} R ⁸ , Ar ¹ , Ar ² , Y ¹ and Y ² may have an anion structure or a cation structure, and R ^{1 to} R ⁸ , Ar ¹ , Ar ² , Y ¹ and Y ² If all are neutral groups, Za is a monovalent counter anion. For example, R ^{1 to} R ⁸ , Ar ¹ , Ar ² , Y ^1, and Y ² have two or more anion structures. If present, Za can also be a counter cation.

R ¹ and R ² each independently represent a hydrocarbon group having 1 to 12 carbon atoms, and preferably an alkyl group having 1 to 12 carbon atoms. The alkyl group may be linear, branched or have a ring structure.
R ¹ and R ² are preferably connected to form a ring.
When R ¹ and R ² are linked to form a ring, the preferred number of ring members is preferably a 5- or 6-membered ring, and most preferably a 6-membered ring.

Ar ¹ and Ar ² each represent a group that forms an aromatic ring, and preferably a group that forms a benzene ring or a naphthalene ring. A substituent may be present on the aromatic ring. Examples of the substituent include alkyl group, alkoxy group, aryloxy group, amino group, alkylthio group, arylthio group, halogen atom, carboxy group, carboxylate group, sulfo group, sulfonate group, alkyloxycarbonyl group, aryloxycarbonyl group, and And a combination of these, and the like, and an alkyl group, a carboxy group, a carboxylate group, a sulfo group, and a sulfonate group are preferable.
Y ¹ and Y ² each independently represent a sulfur atom or a C 1-12 dialkylmethylene group, preferably a C 1-12 dialkylmethylene group, and more preferably a dimethylmethylene group.

R ³ and R ⁴ each independently represent a hydrocarbon group having 1 to 20 carbon atoms, preferably an alkyl group having 1 to 12 carbon atoms. The alkyl group may be linear, branched or have a ring structure. R ³ and R ⁴ are preferably the same group.

At least one of R ³ and R ⁴ is preferably a group represented by the following formula 7.

In Formula 7, L ⁵ represents a divalent hydrocarbon group having 1 to 6 carbon atoms, A ⁻ represents a carboxylate anion, a sulfonate anion, a phosphonate anion, or a phosphinate anion, and ● represents an N atom Represents the binding site.

L ⁵ represents a divalent hydrocarbon group having 1 to 6 carbon atoms, preferably an alkylene group having 1 to 6 carbon atoms, more preferably a linear alkylene group having 1 to 6 carbon atoms, More preferably, it is a linear alkylene group of several 3-5.
A ⁻ represents a carboxylate anion, a sulfonate anion, a phosphonate anion or a phosphinate anion, preferably a carboxylate anion or a sulfonate anion, and more preferably a sulfonate anion.
Further, the counter cation of each anion represented by A ⁻ may be a quaternary ammonium group in Formula 1, or may be an alkali metal cation or an alkaline earth metal cation.
From the viewpoint of improving the water solubility of the compound represented by Formula 1, it is preferable that at least one of R ³ and R ⁴ is a group represented by Formula 7, and both of R ³ and R ⁴ are represented by Formula 7. It is more preferable that it is group represented by these.

R ^{5 to} R ⁸ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and is preferably a hydrogen atom. The alkyl group may be linear, branched or have a ring structure.

In addition, as component D, for example, compounds described in paragraphs 0112 to 0136 of JP 2010-231195 A can be used, but from the viewpoint of solubility in a solvent when preparing an intermediate layer coating solution, From the viewpoint of improving the stain resistance of the obtained lithographic printing plate, it is preferable that the hydrophilicity is high.
Although it does not specifically limit as the component D with high hydrophilicity, The compound as described in Paragraphs 0028-0035 of Unexamined-Japanese-Patent No. 2004-351823, and the compound shown below are used suitably. In the compounds shown below, Ph represents a phenyl group, and Et represents an ethyl group.

  Among the above exemplified compounds, the compounds represented by D-1 to D-30 are particularly preferred from the viewpoint of the hydrophilicity of the compound and the printing durability of the resulting lithographic printing plate.

  Component D may be used alone or in combination of two or more. Component D can be contained in an arbitrary amount in the intermediate layer used in the present invention, but the content of the sensitizing dye is 0.05 to the total solid content of the intermediate layer used in the present invention. It is preferably ˜60% by mass, more preferably 0.1 to 50% by mass, and further preferably 0.2 to 40% by mass.

The compound represented by Formula 1 can be produced, for example, by the methods described in US Pat. No. 5,576,443, JP-T 09-505558, and JP-T 2008-544053. Moreover, it can obtain according to the synthetic method shown below as a synthetic scheme.
For example, as a method for introducing a group represented by any one of the above formula 3-1, formula 3-5 or formula 3-6, a synthesis scheme represented by the following formula S1 to formula S3 is preferably exemplified. As a method for introducing a group represented by any one of the above formulas 3-2 to 3-4, a synthesis scheme represented by the following formula S4 is preferably exemplified.
DMAP represents N, N-dimethylamino-4-pyridine, AcONa represents sodium acetate, NEt ₃ represents triethylamine, and catechol is catechol. R represents a group corresponding to each moiety in Formula 1.

[Component E: Polymer having a repeating unit having a structure that interacts with the surface of the aluminum support]
The intermediate layer used in the present invention may contain, as component E, a polymer having a repeating unit having a structure that interacts with the surface of the aluminum support (hereinafter also referred to as “intermediate layer polymer”). preferable.
The structures that interact with the surface of the aluminum support include carboxylic acid structures, carboxylate structures, sulfonic acid structures, sulfonate structures, phosphonic acid structures, phosphonate structures, phosphate ester structures, and phosphate ester salt structures. , A phenolic hydroxy group, —CONHSO ₂ —, —SO ₂ NHSO ₂ —, or —COCH ₂ COCH ₃ is preferable, and a carboxylic acid structure, a carboxylate structure, a sulfonic acid structure, a sulfonate structure, a phosphonic acid structure, A phosphonate structure, a phosphate ester structure, or a phosphate ester salt structure is more preferable, and a carboxy group, a sulfo group, a phosphate group (—OPO ₃ H ₂ ), a phosphonate group (—PO ₃ H ₂ ), Or these salts are still more preferable.

Moreover, it is preferable that the said component E further has a hydrophilic group and a crosslinkable group from a viewpoint of improving adhesiveness with a photosensitive layer.
As the hydrophilic group, a sulfo group or a salt thereof, or a salt of a carboxy group is preferable.
In addition, the hydrophilic group is preferably a group different from the structure that interacts with the surface of the aluminum support. For example, when a carboxy group salt is used as a structure that interacts with the surface of the aluminum support, it is preferable to use a sulfo group or a salt thereof as the hydrophilic group.
As the crosslinkable group, an ethylenically unsaturated group is preferable, and a methacryl group, an allyl group, and the like are preferable.

Component E is preferably a copolymer of a monomer having a structure that interacts with the surface of the aluminum support, a monomer having a hydrophilic group, and a monomer having a crosslinkable group.
Component E preferably has a repeating unit having a zwitterionic structure.
The zwitterionic structure can be introduced by copolymerizing a monomer having a polar substituent and a substituent having a counter charge with respect to the polar substituent. The polar substituent is preferably a hydrophilic group in the above description. Although it does not specifically limit as a combination of the said polar substituent and the substituent which has a counter charge with respect to the polar substituent, The combination of a sulfo group or a carboxy group, and an ammonium group is mentioned.
The polymer may have a crosslinkable group introduced by salt formation between a polar substituent of the polymer, a substituent having a counter charge with the polar substituent and a compound having an ethylenically unsaturated bond, Other monomers, preferably hydrophilic monomers, may be further copolymerized.

Specifically, a silane coupling agent having an addition-polymerizable ethylenic double bond reactive group described in JP-A-10-282679 and an ethylenic compound described in JP-A-2-304441. The phosphorus compound which has a heavy bond reactive group is mentioned suitably. JP-A-2005-238816, JP-A-2005-125649, JP-A-2006-239867, JP-A-2006-215263, JP-A-2010-231195, JP-A-2012-181249, JP-A-2012-187907 A low molecular or high molecular compound having a crosslinkable group (preferably an ethylenically unsaturated bond group) described in the publication, a functional group that interacts with the support surface, and a hydrophilic group is also preferably used.
More preferably, it has a high adsorptive group, hydrophilic group and crosslinkable group which can be adsorbed on the surface of the support described in JP2010-231195A, JP2012-181249A, and JP2012-187907A. Molecular polymers are mentioned.

The content of the crosslinkable group contained in Component E is preferably 0.1 to 10.0 mmol, more preferably 0.2 to 5.5 mmol, with respect to 1 g of Component E.
The mass average molar mass (weight average molecular weight, Mw) of Component E is preferably 5,000 or more, and more preferably 10,000 to 300,000.

  Although the preferable example of the component E is described below, this invention is not limited to this. In addition, in the following exemplary compounds, a numerical value written together with each repeating unit (a numerical value written together with the main chain repeating unit) represents a mass percentage of the above repeating unit. The numerical value written together with the repeating unit of the side chain indicates the number of repeating parts. Moreover, the description of Mw has shown the value of the mass mean molar mass of the whole polymer.

  Component E may be used alone or in combination of two or more. Component E can be contained in any amount in the intermediate layer used in the present invention, but the content of component E is 1 to 80 mass relative to the total solid content of the intermediate layer used in the present invention. %, More preferably 5 to 75% by mass, and still more preferably 10 to 70% by mass.

[Component G: Polymerization initiator]
The intermediate layer used in the present invention preferably further contains a polymerization initiator as component G.
As the component G, the same polymerization initiator as that of the component A can be used, but from the viewpoint of improving the solubility in a solvent contained in the coating solution for the intermediate layer and the stain resistance which is one of the printing performance, it is hydrophilic. It is preferable to use a high polymerization initiator.
Although the preferable example of the component G used for an intermediate | middle layer is described below, this invention is not limited to this. In the following exemplified compounds, Ph represents a phenyl group, and Me represents a methyl group.

Component G may be added alone or in combination of two or more.
As content of the component G, it is preferable that it is 0.1-50 mass% with respect to the total solid of an intermediate | middle layer, It is still more preferable that it is 0.5-40 mass%, 0.8-30 mass % Is more preferable.

[Other ingredients]
The intermediate layer used in the present invention includes, as other components, a chelating agent, a secondary or tertiary amine, a polymerization inhibitor, an amino group, or a functional group having a polymerization inhibiting ability and an aluminum support, in order to prevent contamination over time. Compounds having groups that interact with the body surface (for example, 1,4-diazabicyclo [2.2.2] octane (DABCO), 2,3,5,6-tetrahydroxy-p-quinone, chloranil, sulfophthalic acid , Hydroxyethylethylenediaminetriacetic acid, dihydroxyethylethylenediaminediacetic acid, hydroxyethyliminodiacetic acid, and the like).

(Formation of intermediate layer)
The intermediate layer in the lithographic printing plate precursor according to the present invention is prepared by, for example, dispersing or dissolving the necessary components in a solvent described later to prepare an intermediate layer coating solution, and applying this to a support such as a bar coater. It can be formed by applying by a method and drying. Coating, the coating amount of the intermediate layer on the support obtained after drying (solid content) may be varied according to the intended purpose, preferably ^{0.1~100mg / m 2, 1~50mg / m} 2 is more preferable. If it is the said range, it is excellent in the printing durability and developability in a lithographic printing plate.

  As the solvent used in preparing the coating solution for the intermediate layer, a known solvent can be used. Specifically, the solvents exemplified as the solvent used in preparing the coating solution for the photosensitive layer are preferable. Can be mentioned. In addition, it is preferable that the solid content concentration in the coating liquid for intermediate | middle layers is 1-50 mass%.

<Protective layer>
The lithographic printing plate of the invention preferably has a protective layer (also referred to as “overcoat layer”) on the photosensitive layer. The protective layer has a function of preventing the formation of scratches in the photosensitive layer and ablation during high-illuminance laser exposure, in addition to the function of suppressing the image formation inhibition reaction by blocking oxygen.
The protective layer used in the present invention preferably contains a polymer having low oxygen permeability, an inorganic layered compound, and other components.
The protective layer used in the present invention may have a structure in which two or more layers are laminated, such as a lower protective layer and an upper protective layer.

[Polymer with low oxygen permeability]
The protective layer having such characteristics is described in, for example, US Pat. No. 3,458,311 and Japanese Patent Publication No. 55-49729. As the low oxygen permeability polymer used for the protective layer, either a water-soluble polymer or a water-insoluble polymer can be appropriately selected and used, and two or more types can be mixed and used as necessary. it can. Specific examples include polyvinyl alcohol, modified polyvinyl alcohol, polyvinyl pyrrolidone, water-soluble cellulose derivatives, poly (meth) acrylonitrile, and the like.
As the modified polyvinyl alcohol, acid-modified polyvinyl alcohol having a carboxy group or a sulfo group is preferably used. Specifically, modified polyvinyl alcohols described in JP-A-2005-250216 and JP-A-2006-259137 are preferable.

The low oxygen permeability polymer may be used alone or in combination of two or more.
0-60 mass% is preferable with respect to the total solid content of a protective layer, and, as for content of a polymer with low oxygen permeability, 3-50 mass% is more preferable. When the content is in the above range, the image forming sensitivity of the lithographic printing plate precursor becomes good.

[Inorganic layered compound]
The protective layer in the present invention preferably contains an inorganic layered compound in order to enhance oxygen barrier properties. The inorganic layered compound is a particle having a thin flat plate shape, such as natural mica, mica group such as synthetic mica, talc, teniolite, montmorillonite, saponite, hectorite represented by the formula 3MgO · 4SiO · H ₂ O. And zirconium phosphate.
The inorganic layered compound preferably used in the present invention is a mica compound. As the mica compound, for example, the formula: A (B, C) _2-5 D ₄ O ₁₀ (OH, F, O) ₂ [where A is one of K, Na, Ca, B and C are One of Fe (II), Fe (III), Mn, Al, Mg, and V, and D is Si or Al. ] Mica groups such as natural mica and synthetic mica represented by

In the mica group, natural mica includes muscovite, soda mica, phlogopite, biotite, and sericite. Synthetic fluorine phlogopite KMg ₃ as mica (AlSi ₃ O10) F _2, potassium tetrasilic mica KMg _2.5 Si ₄ O ₁₀₎ non-swellable mica ₂ such F, and, Na tetrasilylic mica NaMg _2.5 (Si ₄ O ₁₀ ) F ₂ , Na or Li Teniolite (Na, Li) Mg ₂ Li (Si ₄ O ₁₀ ) F ₂ , Montmorillonite Na or Li Hectorite (Na, Li) _1/8 Mg _2/5 Li _1/8 Examples include swellable mica such as (Si ₄ O ₁₀ ) F ₂ . Synthetic smectite is also useful.

In the present invention, among the mica compounds, fluorine-based swellable mica is particularly useful. That is, the swellable synthetic mica has a laminated structure composed of unit crystal lattice layers with a thickness of about 10 to 15 mm (1 to 1.5 nm), and the metal atom substitution in the lattice is significantly larger than other clay minerals. As a result, the lattice layer is deficient in positive charge, and in order to compensate for this, cations such as Li ⁺ , Na ⁺ , Ca ²⁺ and Mg ²⁺ are adsorbed between the layers. The cations present between these layers are called exchangeable cations and exchange with various cations. In particular, when the cation between the layers is Li ⁺ or Na ⁺ , since the ionic radius is small, the bond between the layered crystal lattices is weak, and the layer swells greatly with water. If shear is applied in this state, it will easily cleave and form a stable sol in water. Swellable synthetic mica has a strong tendency and is particularly preferably used in the present invention.

  The shape of the mica compound is preferably as small as possible from the viewpoint of diffusion control, and the plane size is preferably as long as the smoothness of the coated surface and the transmittance of actinic rays are not impaired. Therefore, the aspect ratio is preferably 20 or more, more preferably 100 or more, and particularly preferably 200 or more. The aspect ratio is the ratio of the major axis to the thickness of the particle, and can be measured from, for example, a projection drawing of a micrograph of the particle. The larger the aspect ratio, the greater the effect that can be obtained.

  The average major axis of the mica compound has a mean major axis of preferably 0.3 to 20 μm, more preferably 0.5 to 10 μm, and particularly preferably 1 to 5 μm. The average thickness of the particles is preferably 0.1 μm or less, more preferably 0.05 μm or less, and particularly preferably 0.01 μm or less. Specifically, for example, in the case of swellable synthetic mica, which is a representative compound, as a preferred embodiment, the thickness is 1 to 50 nm and the surface size (major axis) is about 1 to 20 μm.

  0-60 mass% is preferable with respect to the total solid content of a protective layer, and, as for content of an inorganic layered compound, 3-50 mass% is more preferable. Even when a plurality of kinds of inorganic layered compounds are used in combination, the total amount of the inorganic layered compounds is preferably the above-described mass. Within the above range, the oxygen barrier property is improved and good sensitivity is obtained. Further, it is possible to prevent a decrease in inking property.

[Other ingredients]
The protective layer may contain known additives such as a plasticizer for imparting flexibility, a surfactant for improving coating properties, and inorganic fine particles for controlling surface slipperiness. Further, the protective layer may contain the sensitizer described in the photosensitive layer.

(Formation of protective layer)
The protective layer in the lithographic printing plate precursor according to the invention is prepared by, for example, dispersing or dissolving each of the necessary components in a known solvent to prepare a coating solution for the protective layer, and applying this to the support on a support such as a bar coater It can be formed by applying by a method and drying. Coating, as the coating amount of the protective layer on the support obtained after drying of the coating amount after drying is preferably 0.01 to 10 g / m ^2, more preferably 0.02~3g / m ^2, 0. 02-1 g / m ² is particularly preferred.

(Lithographic printing plate and plate making method)
The lithographic printing plate in the present invention is a lithographic printing plate obtained by making the lithographic printing plate precursor of the present invention.
The plate making method of the lithographic printing plate of the present invention is not particularly limited, but as a first aspect, an exposure step of imagewise exposing the lithographic printing plate precursor of the present invention, and the lithographic printing plate precursor subjected to imagewise exposure It is preferable to include a solution development processing step of removing the unexposed portion of the substrate with a developer having a pH of 2 to 12.
The second embodiment of the plate making method of the lithographic printing plate of the present invention includes an exposure step of imagewise exposing the lithographic printing plate precursor of the present invention, and an unexposed portion of the lithographic printing plate precursor subjected to imagewise exposure. It is preferable to include an on-press development processing step of supplying and removing printing ink and / or dampening water on a printing press.
In the above two preferred embodiments, the exposure process is common, and it is different whether the unexposed portion is removed by the solution development process or the on-machine development process.
Hereinafter, the exposure process, the solution development process, and the on-press development process included in the lithographic printing plate making method of the present invention will be described.

<Exposure process>
The plate making method of the lithographic printing plate of the present invention preferably includes an exposure step of imagewise exposing the lithographic printing plate precursor of the present invention.
The planographic printing plate precursor of the present invention can be exposed imagewise by a method in which digital data is scanned and exposed with an infrared laser or the like.
The wavelength of the light source is preferably 750 to 1,400 nm. As a light source of 750 to 1,400 nm, a solid-state laser and a semiconductor laser that emit infrared rays are suitable. The exposure mechanism may be any of an internal drum system, an external drum system, a flat bed system, and the like.
The exposure step can be performed by a known method using a plate setter or the like. Alternatively, the printing may be performed on the printing machine after the lithographic printing plate precursor is mounted on the printing machine using a printing machine equipped with an exposure device.

<Solution development process>
In the solution development processing step, the unexposed portion of the lithographic printing plate precursor that has been imagewise exposed is removed with a developer having a pH of 2 to 12.
The developer has a pH of 2 to 12, preferably 5 to 10.7, more preferably 6 to 10.5, and still more preferably 7.5 to 10.3.

Although it does not specifically limit as said developing solution, The developing solution which contains 60 mass% or more of water with respect to the total mass of a developing solution is preferable.
The developer preferably contains a surfactant or a water-soluble polymer.
The surfactant is not particularly limited, and anionic, nonionic, cationic, or zwitterionic surfactants can be used.
Although it does not specifically limit as said water-soluble polymer, Soy polysaccharide, modified starch, gum arabic, dextrin, a fiber derivative (For example, carboxymethylcellulose, carboxyethylcellulose, methylcellulose etc.) and its modified body, pullulan, polyvinyl alcohol, and its Derivatives, polyvinylpyrrolidone, polyacrylamide and acrylamide copolymers, vinyl methyl ether / maleic anhydride copolymers, vinyl acetate / maleic anhydride copolymers, styrene / maleic anhydride copolymers, and the like.
The developer may contain a pH buffer, an organic solvent, an antiseptic, a chelate compound, an antifoaming agent, an organic acid, an inorganic acid, an inorganic salt, and the like as other compounds.
As preferred embodiments of the surfactant, the water-soluble polymer, and other compounds, the compounds described in paragraphs 0156 to 0169 of JP2010-231195A can be used.

<On-machine development process>
In the on-press development process, printing ink and / or fountain solution is supplied as it is without performing any development process on the image-exposed lithographic printing plate precursor. The unexposed portion of the lithographic printing plate precursor is removed, and the hydrophilic support surface is exposed along with it to form a non-image portion. As the printing ink and fountain solution, known lithographic printing ink and fountain solution are used. Here, printing ink or dampening water may be supplied to the printing plate first, but the printing ink is first supplied in order to prevent the dampening water from being contaminated by the removed photosensitive layer components. It is preferable to do.
In this way, the lithographic printing plate precursor is subjected to on-press development on an offset printing machine and used as it is for printing a large number of sheets.

  The plate-making method of the lithographic printing plate of the present invention may include other known steps in addition to the above steps.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these. In this example, “parts” and “%” mean “parts by mass” and “mass%” unless otherwise specified. In the polymer compound, except for those specifically defined, the molecular weight is a mass average molar mass (Mw) in terms of polystyrene converted by the GPC method, and the ratio of repeating units is a mole percentage.
In addition, the compounds D-1 to D-33, the compounds E-1 to E-19, the compounds F-1 to F-29, and the compounds G-1 to G-14 used in the examples are the compounds D described above. -1 to D-33, compounds E-1 to E-19, compounds F-1 to F-29, and compounds G-1 to G-14.

(Examples 1-16 and Comparative Examples 1-7)
1. Preparation of on-press development type lithographic printing plate precursor (for Examples 1 to 16 and Comparative Examples 1 to 7) <Preparation of lithographic printing plate precursor A-1>

(Production of support)
In order to remove rolling oil on the surface of a 0.3 mm thick aluminum plate (material JIS A 1050), after degreasing at 50 ° C. for 30 seconds using a 10 mass% sodium aluminate aqueous solution, the hair diameter is 0.3 mm. The surface of the aluminum plate was grained using 3 bundle-planted nylon brushes and a pumice-water suspension (specific gravity 1.1 g / cm ³ ) having a median diameter of 25 μm and washed well with water. Etching was performed by immersing the aluminum plate in a 25 mass% sodium hydroxide aqueous solution at 45 ° C for 9 seconds, washing with water, and further immersed in a 20 mass% nitric acid aqueous solution at 60 ° C for 20 seconds, followed by washing with water. The etching amount on the grained surface was about 3 g / m ² .

Next, an electrochemical roughening treatment was performed continuously using an alternating voltage of 60 Hz. The electrolytic solution was a 1% by mass aqueous nitric acid solution (containing 0.5% by mass of aluminum ions), and the liquid temperature was 50 ° C. The AC power source waveform is electrochemical roughening treatment using a trapezoidal rectangular wave alternating current with a time ratio TP of 0.8 msec until the current value reaches a peak from zero, a duty ratio of 1: 1, and a trapezoidal rectangular wave alternating current. Went. Ferrite was used for the auxiliary anode. The current density was 30 A / dm ² at the peak current value, and 5% of the current flowing from the power source was shunted to the auxiliary anode. The amount of electricity in the nitric acid electrolysis was 175 C / dm ² when the aluminum plate was the anode. Then, water washing by spraying was performed.

Subsequently, nitric acid electrolysis was performed in an aqueous solution containing 0.5% by mass of hydrochloric acid (containing 0.5% by mass of aluminum ions) and an electrolytic solution having a liquid temperature of 50 ° C. with an aluminum plate serving as an anode with an electric quantity of 50 C / dm ^2. Electrochemical surface roughening treatment was carried out in the same manner as above, followed by washing with water by spraying.
Next, a 2.5 g / m ² direct current anodic oxide film having a current density of 15 A / dm ² is provided on an aluminum plate as an electrolyte using a 15 mass% sulfuric acid aqueous solution (containing 0.5 mass% of aluminum ions), and then washed with water. The support A was prepared by drying.
Thereafter, in order to ensure the hydrophilicity of the non-image area, the support A was subjected to silicate treatment at 60 ° C. for 10 seconds using a 2.5 mass% No. 3 sodium silicate aqueous solution, and then washed with water to obtain the support B. Produced. The adhesion amount of Si was 10 mg / m ² . The center line average roughness (Ra) of the support was measured using a needle having a diameter of 2 μm and found to be 0.51 μm.

(Formation of intermediate layer)
Next, the following intermediate layer coating solution (1) was applied onto the support B so that the dry coating amount was 38 mg / m ² to prepare a support having an intermediate layer.

<Intermediate layer coating solution (1)>
Component E: Intermediate layer polymer (E-1): 0.18 parts Hydroxyethyliminodiacetic acid: 0.05 parts Polymerization initiator (G-12): 0.10 parts Component D: sensitizing dye (D-1): 0.05 part Methanol: 55.24 parts Water: 6.15 parts

  Component D used in the examples was synthesized according to the description in US Pat. No. 5,576,443. Moreover, about the component D which has group represented by the said Formula 3, it synthesize | combined according to the scheme of said S1-S4. As a specific example, a method for synthesizing the sensitizing dye D-2 is shown below.

-Synthesis of SM-2-
SM-1 5.00 g (7.45 mmol), potassium carbonate (K ₂ CO ₃ ) 1.90 g (13.7 mmol), catechol 0.82 g (7.45 mmol), 1- (4-pyridyl) iso Acetone solution (30 mL) of 5.69 g (37.6 mmol) of butanol was stirred at room temperature for 30 minutes. The reaction solution was added dropwise to water (250 mL), and the precipitated solid was further washed with water and collected by filtration. A solid solution produced by adding dropwise a mixed solution of hexane (320 mL) -ethyl acetate (80 mL) to an ethyl acetate (80 mL) -acetone (20 mL) solution of the obtained solid is collected by filtration, and SM-2. 54 g (3.23 mmol) were obtained. The yield was 43%.

-Synthesis of sensitizing dye D-2-
SM-2 1.00 g (1.27 mmol), 1,4-butane sultone 1.44 g (6.36 mmol), and N, N-dimethylformamide 2.00 g were stirred at 80 ° C. for 8 hours. The reaction solution was added dropwise to 10 mL of ethyl acetate, and the precipitated solid was collected by filtration. The obtained solid was dissolved in 30 mL of acetone and 5 mL of methanol, added dropwise to 30 mL of ethyl acetate, and the precipitated solid was collected by filtration. The obtained solid was vacuum-dried to obtain 0.67 g (0.73 mmol) of D-2. The yield was 57%.

<Formation of photosensitive layer>
The photosensitive layer coating solution (1) is bar-coated on the intermediate layer formed as described above, and oven-dried at 100 ° C. for 60 seconds to form a photosensitive layer having a dry coating amount of 1.0 g / m ^2. did.
The photosensitive layer coating solution (1) was prepared by mixing and stirring the following photosensitive solution and microgel solution immediately before coating.

<Photosensitive solution>
Polymerization initiator (1) [Structure below]: 0.245 parts Binder polymer (1): 0.240 parts Sensitizing dye represented by formula (C-1): 0.023 parts Component B: Polymerizable compound Tris (acryloyloxyethyl) isocyanurate (NK ester A-9300, manufactured by Shin-Nakamura Chemical Co., Ltd.): 0.192 parts Low molecular weight hydrophilic compound Tris (2-hydroxyethyl) isocyanurate: 0.062 Parts ・ Low molecular weight hydrophilic compound (1) [following structure]: 0.050 part ・ Sensitizing agent Phosphonium compound (1) [following structure]: 0.055 part ・ Sensitizing agent benzyl-dimethyl-octylammonium PF ₆ salt: 0.018 part Grease-sensitizing agent Ammonium group-containing polymer [the following structure, reduced specific viscosity 44 ml / g]: 0.035 part Fluorosurfactant (1) [the following structure]: 0 .008 parts-2-butanone: 1.091 parts-1-methoxy-2-propanol: 8.609 parts

<Microgel solution>
Microgel (1): 2.640 parts Distilled water: 2.425 parts

  Polymerization initiator (1), sensitizing dye (C-1), binder polymer (1), fluorine-based surfactant (1), low molecular weight hydrophilic compound (1), and phosphonium compound (1) used in the above photosensitive solution. ), The structure of the ammonium group-containing polymer is as shown below. In addition, in the following structure, the numerical value written together with each repeating unit (the numerical value written together with the main chain repeating unit) represents the mass percentage of the repeating unit. The numerical value written together with the repeating unit of the side chain indicates the number of repetitions of the above repeating site, and Me indicates a methyl group. Moreover, the description of Mw has shown the value of the mass mean molar mass of the whole polymer.

A method for preparing the microgel (1) used in the microgel solution is shown below.
<Preparation of microgel (1)>
As oil phase components, trimethylolpropane and xylene diisocyanate adduct (Mitsui Chemicals, Takenate D-110N) 10 g, pentaerythritol triacrylate (Nippon Kayaku Co., Ltd., SR444) 3.15 g and alkylbenzene 0.1 g of sulfonate (manufactured by Takemoto Yushi Co., Ltd., Pionein A-41C) was dissolved in 17 g of ethyl acetate. As an aqueous phase component, 40 g of a 4% by mass aqueous solution of polyvinyl alcohol (PVA-205 manufactured by Kuraray Co., Ltd.) was prepared. The oil phase component and the aqueous phase component were mixed and emulsified for 10 minutes at 12,000 rpm using a homogenizer. The obtained emulsion was added to 25 g of distilled water, stirred at room temperature for 30 minutes, and then stirred at 50 ° C. for 3 hours. A microgel (1) was prepared by diluting the solid content concentration of the microgel solution thus obtained with distilled water so as to be 15% by mass. The average particle size of the microgel was measured by a light scattering method and found to be 0.2 μm.

<Formation of protective layer>
On the photosensitive layer, a protective layer coating solution having the following composition was further bar-coated and oven-dried at 120 ° C. for 60 seconds to form a protective layer having a dry coating amount of 0.15 g / m ^2. An original plate A-1 was prepared.

<Coating liquid for protective layer>
Inorganic layered compound dispersion (1): 1.5 parts Polyvinyl alcohol (CKS50 manufactured by Nippon Synthetic Chemical Industry Co., Ltd., sulfonic acid modification, saponification degree 99 mol% or more, polymerization degree 300) 6% by mass Aqueous solution: 0. 55 parts ・ Polyvinyl alcohol (PVA-405 manufactured by Kuraray Co., Ltd., saponification degree 81.5 mol%, polymerization degree 500) 6 mass% aqueous solution: 0.03 part ・ Polyoxyethylene lauryl ether (Nihon Emulsion Co., Ltd. interface) Activator EMALEX 710 1 mass% aqueous solution): 0.86 parts ・ Ion-exchanged water: 6.0 parts

A method for preparing the inorganic layered compound dispersion (1) used in the protective layer coating solution is shown below.
<Preparation of inorganic layered compound dispersion (1)>
6.4 g of synthetic mica (Somasif ME-100, manufactured by Co-op Chemical Co., Ltd.) was added to 193.6 g of ion-exchanged water, and dispersed using an homogenizer until the average particle size (laser scattering method) became 3 μm. The aspect ratio of the obtained dispersed particles was 100 or more.

<Preparation of lithographic printing plate precursors A-2 to A-16 and R-1 to R-7>
Component D, component E, and polymerization initiator in the intermediate layer coating solution, and the sensitizing dye and reducing agent in the photosensitive layer coating solution, except for the compounds and coating amounts shown in Table 1 below, The lithographic printing plate precursors A-2 to A-16 and R-1 to R-7 were prepared in the same manner as the lithographic printing plate precursor A-1. In addition, the numerical value of the coating amount in Table 1 represents the amount of compound (mg / m ² ) contained in the photosensitive layer or the intermediate layer after the formation of each lithographic printing plate precursor, and “-” does not contain the corresponding component. Represents that.

  C-2 in Table 1 represents the following compound.

2. Evaluation of lithographic printing plate The lithographic printing plate obtained using the on-machine development type lithographic printing plate precursor was evaluated for plate inspection, stain resistance and printing durability as follows. The evaluation results are shown in Table 2.
(1) Plate inspection property The lithographic printing plate precursor is stored in an oven at 60 ° C. for 2 days, and then output 11.7 W, external drum rotation speed 250 rpm, resolution 2 with a Creo Trendsetter 3244VX equipped with a water-cooled 40 W infrared semiconductor laser. , Exposure was performed at 400 dpi. The exposed lithographic printing plate precursor was allowed to stand for 30 minutes in a dark place at 25 ° C. and in an atmosphere with a relative humidity of 50%, and then the plate inspection property was evaluated. The plate inspection property was evaluated by the difference ΔL between the L value of the exposed area and the L value of the unexposed area using the L value (brightness) of the L ^* a ^* b ^* color system. The larger the value of ΔL, the better the plate inspection property. The measurement was performed by the SCE (regular reflection light removal) method using a spectrocolorimeter CM2600d manufactured by KONICA-MINOLTA and operation software CM-S100W. In the SCE method, specularly reflected light is removed and only diffused light is measured. Therefore, the color is evaluated almost visually and correlates well with the plate inspection by an actual person. The evaluation results are shown in Table 2.

(2) Stain resistance The lithographic printing plate precursor was subjected to an external drum rotation speed of 1,000 rpm, a laser output of 70%, and a resolution of 2,400 dpi using a FUJIFILM Corporation Luxel PLASETTER T-6000III equipped with an infrared semiconductor laser. Exposed. The exposure image included a solid image and a 50% halftone dot chart of a 20 μm dot FM screen.
The exposed lithographic printing plate precursor was mounted on the plate cylinder of a printing machine LITHRONE 26 manufactured by Komori Corporation without developing. Equality-2 (manufactured by FUJIFILM Corporation) / tap water = 2/98 (volume ratio) dampening water and Values-G (N) black ink (manufactured by Dainippon Ink & Chemicals, Inc.) Dampening water and ink were supplied by the standard automatic printing start method of LITHRONE 26, and printing was performed on Tokuhishi Art (76.5 kg) paper at a printing speed of 10,000 sheets per hour.
The printed material on the 20th sheet was taken out after the start of printing, and the stain resistance was evaluated based on the ink density adhered to the non-image area. Ink adhesion on the non-image area does not always occur uniformly, and thus was indicated by a visual evaluation score per 75 cm ² . The score for visual evaluation is 10 points when the ink adhesion area ratio of the non-image area is 0%, 9.0 points for 1 to 10%, 8.5 points for 11 to 15%, and 8. points for 16 to 20%. 0 points, 21-30% 7.0 points, 31-40% 6.0 points, 41-50% 5.0 points, 51-60% 4.0 points, 61-70% 3. 0 points, 71 to 80% were set to 2.0 points, 81 to 90% were set to 1.0 points, and 91 to 100% were set to 0 points. The higher the score, the better the stain resistance. The evaluation results are shown in Table 2.

(3) Printing durability After the evaluation of the stain resistance, printing was further continued. As the number of printed sheets was increased, the photosensitive layer was gradually worn out, so that the ink density on the printed material decreased. When the value measured by the Gretag densitometer on the 50% halftone dot area of the FM screen in the printed material is 5% lower than the measured value for the 100th printed sheet, it is regarded as completed, and the number of copies until completion is confirmed. did. The relative printing durability was evaluated with 100 points when the number of copies to be printed was 50,000. The higher the score, the better the printing durability. The evaluation results are shown in Table 2.
Relative printing durability = (number of printed copies of target original plate) / 50,000 x 100 (points)

  From the results of Table 2, the lithographic printing plate precursor of the present invention exhibits excellent stain resistance equivalent to that of the lithographic printing plate precursor in the comparative example in which the photosensitive layer configuration and the component E in the intermediate layer are the same, Compared with the lithographic printing plate precursors of the respective comparative examples, extremely good printing durability was exhibited. Furthermore, the lithographic printing plate precursor according to the invention exhibited better plate inspection properties than the lithographic printing plate precursor in the comparative example.

(Examples 17-22 and Comparative Examples 8-11)
1. Preparation of developer-processed planographic printing plate precursor (for Examples 17 to 22 and Comparative Examples 8 to 11) <Preparation of planographic printing plate precursor A-17>
(Formation of intermediate layer)
On the support B, the following intermediate layer coating solution (2) was coated with a wire bar and dried at 90 ° C. for 30 seconds. The dry coating amount was 15 mg / m ² .

<Intermediate layer coating solution (2)>
-Component E: Intermediate layer polymer (E-13): 0.050 part-Component D: Sensitizing dye (D-3): 0.025 part-Methanol: 27 parts-Ion-exchanged water: 3 parts

[Formation of photosensitive layer]
The following photosensitive layer coating solution (2) was prepared, applied onto the intermediate layer formed as described above using a wire bar, and dried to form a photosensitive layer. Drying was performed at 125 ° C. for 34 seconds using a warm air dryer. The coating amount after drying was 1.4 g / m ² .

<Coating solution for photosensitive layer (2)>
-Polymerization initiator (1): 0.245 parts-Sensitizing dye represented by formula (C-1): 0.023 parts-Reducing agent represented by formula (F-2): 0.011 parts Component B: Polymerizable compound Pentaerythritol triacrylate Hexamethylene diisocyanate Urethane prepolymer (UA-306H, manufactured by Kyoeisha Chemical Co., Ltd.): 1.33 parts Binder polymer (2) [the following structure]: 1.35 parts Ethyl violet: 0.04 part ・ Fluorosurfactant MegaFac F-780-F (manufactured by DIC Corporation) Methyl isobutyl ketone (MIBK) 30% by mass solution: 0.025 part ・ Methyl ethyl ketone: 18.4 parts Methanol: 9.83 parts 1-methoxy-2-propanol: 18.4 parts

  The structure of the binder polymer (2) is as shown below. In addition, in the following structure, the numerical value written together with each repeating unit (the numerical value written together with the main chain repeating unit) represents the mass percentage of the repeating unit. Moreover, the description of Mw has shown the value of the mass mean molar mass of the whole polymer.

<Formation of lower protective layer>
On the photosensitive layer, synthetic mica (Somasif MEB-3L, 3.2 mass% aqueous dispersion, manufactured by Co-op Chemical Co., Ltd.), polyvinyl alcohol (Goceran CKS-50, saponification degree 99 mol%, polymerization degree 300, Sulfonic acid-modified polyvinyl alcohol, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.), surfactant A (Emalex 710, manufactured by Nippon Emulsion Co., Ltd.) and surfactant B (Adeka Pluronic P-84, manufactured by ADEKA Corporation) A mixed aqueous solution (coating liquid for forming the lower protective layer) was applied with a wire bar, and dried at 125 ° C. for 30 seconds with a hot air dryer.
The content ratio of synthetic mica (solid content) / polyvinyl alcohol / surfactant A / surfactant B in the coating solution for forming the lower protective layer is 7.5 / 89/2 / 1.5 (mass%). Yes, the coating amount after drying was 0.5 g / m ² .

<Formation of upper protective layer>
On the lower protective layer, organic filler (Art Pearl J-7P, manufactured by Negami Industrial Co., Ltd.), synthetic mica (Somasif MEB-3L, 3.2% aqueous dispersion, manufactured by Coop Chemical Co., Ltd.), polyvinyl alcohol (L-3266: Saponification degree 87 mol%, polymerization degree 300, sulfonic acid-modified polyvinyl alcohol, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.), thickener (Serogen FS-B, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) And a surfactant (Emalex 710, manufactured by Nippon Emulsion Co., Ltd.) mixed aqueous solution (coating solution for forming the upper protective layer) was applied with a wire bar, and dried at 125 ° C. for 30 seconds with a hot air dryer. .
The content ratio of the organic filler / synthetic mica (solid content) / polyvinyl alcohol / thickener / surfactant in the coating solution for forming the upper protective layer is 3.2 / 2.0 / 80.5 / 11.5. /2.8 (mass%), and the coating amount after drying was 1.76 g / m ² .
Through the above steps, a lithographic printing plate precursor A-17 was prepared.

<Preparation of lithographic printing plate precursors A-18 to A-22 and R-8 to R-11>
The lithographic printing plate precursor A- is produced in the same manner as the lithographic printing plate precursor A-17, except that the components D, E and polymerization initiator in the intermediate layer are the compounds and coating amounts shown in Table 3 below. 18-A-22 and R-8-R-11 were produced.
In addition, the numerical value of the coating amount in Table 3 represents the amount of compound (mg / m ² ) contained in the intermediate layer after the formation of each lithographic printing plate precursor, and “-” represents that the corresponding component is not contained. ing.

[Plate making method]
The obtained developer-processed lithographic printing plate precursor was processed according to each step of image exposure, development processing, and drying.
Image exposure was performed with an infrared semiconductor laser (Trendsetter 3244VX manufactured by Creo, equipped with a water-cooled 40 W infrared semiconductor laser) under conditions of an output of 9 W, an outer drum rotating speed of 210 rpm, and a resolution of 2,400 dpi. A solid image was used for printing durability evaluation.
After the exposure, the substrate is washed with water in order to remove the protective layer, and then developed with a 1: 4 water dilution of a developer HN-D (former product name: DH-N) manufactured by Fujifilm Corporation. Carried out. The pH of the developer was 12, and the temperature of the developer bath was 30 ° C. The developer was showered from the spray pipe with a circulation pump and supplied to the plate surface of the lithographic printing plate precursor. The tank capacity of the developer was 10 liters. After development, a water washing treatment was performed to remove the developer adhering to the plate surface. Thereafter, air-drying at 50 ° C. for 2 seconds was performed to prepare a lithographic printing plate.

2. Evaluation of lithographic printing plate The obtained lithographic printing plate was attached to a plate cylinder of a printing machine LITHRONE26 manufactured by Komori Corporation, and in the same manner as described in the above on-press development type lithographic printing plate precursor, The printing durability was evaluated. The results are shown in Table 4.

  From the results of Table 4, the planographic printing plate precursor of the present invention exhibits excellent stain resistance equivalent to that of the comparative planographic printing plate precursor having the same photosensitive layer constitution and component E in the intermediate layer. It is clear that extremely good printing durability is exhibited as compared with the lithographic printing plate precursors of the comparative examples. Moreover, although data is not described, when the plate inspection property in the lithographic printing plate after exposure was evaluated in the same manner as in Examples 1 to 16 and Comparative Examples 1 to 7, the lithographic printing plate precursors in Examples 17 to 22 were evaluated. Exhibited a good plate inspection property as compared with the planographic printing plate precursor of the comparative example in which the component of the photosensitive layer and the component E in the intermediate layer were the same.

Claims (11)

On the aluminum support, it has an intermediate layer and a photosensitive layer in this order,
The photosensitive layer contains, as component A, a polymerization initiator, and as component B, a polymerizable compound,
The lithographic printing plate precursor, wherein the intermediate layer contains, as component D, a sensitizing dye, and as component E, a polymer having a repeating unit having a structure that interacts with the surface of the aluminum support. . The lithographic printing plate precursor as claimed in claim 1, wherein the component D comprises a compound represented by the following formula 1.

In Formula 1, X ¹ represents a hydrogen atom, a halogen atom, or a group represented by the following Formulas 2 to 6, Za represents a counter ion that neutralizes charge, and R ¹ and R ² are each independently Represents a hydrocarbon group having 1 to 12 carbon atoms, Ar ¹ and Ar ² represent a group forming an aromatic ring, and Y ¹ and Y ² each independently represent a sulfur atom or a dialkylmethylene having 1 to 12 carbon atoms. R ³ and R ⁴ each independently represents a hydrocarbon group having 1 to 20 carbon atoms, and R ^{5 to} R ⁸ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms. .

In formula 2 to formula 6, L ^{1 to} L ⁴ may each independently contain a carbonyl group, a sulfonyl group, or —N (R ^N ) —, ═N—, —S—, or —O—. represents a hydrocarbon group having a carbon number of 1 to 20, R ^N represents a hydrogen atom, an alkyl group or an aryl group, Ra represents an alkyl group, an aryl group, an amino group, or a halogen atom, n1 is 0 to 5 Zb represents a counter ion that neutralizes the charge, and ● represents a binding site with another structure.   The lithographic printing plate precursor as claimed in claim 2, wherein the compound represented by Formula 1 has a zwitterionic structure. The lithographic printing plate precursor according to claim 2 or 3, wherein at least one of R ³ and R ⁴ is a group represented by the following formula 7.

In Formula 7, L ⁵ represents a divalent hydrocarbon group having 1 to 6 carbon atoms, A ⁻ represents a carboxylate anion, a sulfonate anion, a phosphonate anion, or a phosphinate anion, and ● represents an N atom Represents the binding site. The lithographic printing plate precursor as claimed in any one of claims 2 to 4, wherein X ¹ is a group represented by the following formula 8.

In Formula 8, R ⁹ and R ¹⁰ each independently represent a hydrogen atom, an alkyl group or an aryl group, X ² represents an onium group, and ● represents a bonding site with another structure. The lithographic printing plate precursor as claimed in claim 5, wherein X ² is a group represented by the following formula 9.

In Formula 9, each R ¹¹ independently represents a halogen atom, an alkyl group, an aryl group, a hydroxy group, or an alkoxy group, and a plurality of R ¹¹ may be linked to form a ring, and n2 is 0 Represents an integer of ˜4, R ¹² represents an alkyl group or an aryl group, Zc represents a counter ion that neutralizes charge, and ● represents a binding site with another structure.   The lithographic printing plate precursor according to any one of claims 1 to 6, wherein the intermediate layer contains a polymerization initiator as component G.   As a structure in which component E interacts with the surface of the aluminum support, a carboxylic acid structure, a carboxylate structure, a sulfonic acid structure, a sulfonate structure, a phosphonic acid structure, a phosphonate structure, a phosphate ester structure, or The lithographic printing plate precursor as claimed in any one of Claims 1 to 7, comprising a phosphate ester salt structure.   The lithographic printing plate precursor as claimed in any one of Claims 1 to 8, wherein Component E comprises a repeating unit having a zwitterionic structure. An exposure step of imagewise exposing the lithographic printing plate precursor according to any one of claims 1 to 9, and
A plate making method of a lithographic printing plate, comprising a solution development treatment step of removing an unexposed portion of the lithographic printing plate precursor subjected to imagewise exposure with a developer having a pH of 2 to 12. An exposure step of imagewise exposing the lithographic printing plate precursor according to any one of claims 1 to 9, and
A plate making method of a lithographic printing plate, comprising: an on-press development processing step of removing an unexposed portion of the lithographic printing plate precursor subjected to imagewise exposure by supplying printing ink and / or dampening water on a printing press.