JP2006259112A - Photosensitive composition, and photosensitive lithographic printing plate and image recording method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive composition using a new photoinitiation system, having high sensitivity to an oscillation wavelength of 350-450 nm of an inexpensive short-wavelength semiconductor laser, and excellent in storage stability, work efficiency, economical efficiency, printing durability and fouling resistance, and to provide a photosensitive lithographic printing plate and an image recording method using the composition. <P>SOLUTION: The photosensitive composition contains (A) a mercapto compound represented by the formula (I): A-SH (where A represents a heterocyclic compound which may have a substituent) and having a volume of ≥215 Å<SP>3</SP>, (B) a hexaarylbiimidazole compound, (C) a sensitizing dye and (D) a polymerizable compound having an ethylenically unsaturated double bond. The photosensitive lithographic printing plate and the image recording method using the composition are also provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is a photosensitivity that can be used for image forming materials such as three-dimensional stereolithography, holography, planographic printing plates, color proofs, photoresists, and color filters, and photocurable resin materials such as inks, paints, and adhesives. Relates to the composition. More particularly, the present invention relates to a photosensitive composition that can be directly made from a digital signal of a computer or the like using various lasers, and is suitably used as a so-called lithographic printing plate material capable of direct plate making.

Conventionally, as a lithographic printing plate, a PS plate having a configuration in which a lipophilic photosensitive resin layer is provided on a hydrophilic support has been widely used. As the plate making method, usually, mask exposure (surface After exposure), the desired printing plate was obtained by dissolving and removing the non-image area.
In recent years, digitization techniques for electronically processing, storing, and outputting image information using a computer have become widespread, and various new image output methods corresponding to the technology have come into practical use. As a result, computer-to-plate (CTP) technology that scans highly directional light such as laser light in accordance with digitized image information and directly manufactures a printing plate without using a lith film is desired. Obtaining a printing plate precursor adapted to this is an important technical issue.

  As one of methods for obtaining such a lithographic printing plate capable of scanning exposure, a method of forming an ink receptive resin layer region on a support having a hydrophilic surface is employed. This is a material in which a negative photosensitive layer that is cured by scanning exposure to form an ink receptive region is provided on a support, and has a configuration using a photopolymerization composition excellent in photosensitive speed. Some have been proposed and are already in practical use. The photosensitive lithographic printing plate having such a constitution has a desirable printing plate and printing performance such that the development process is simple, and further, it is excellent in resolution, inking property, printing durability and stain resistance.

The photosensitive composition basically contains a polymerizable compound having an ethylenically unsaturated bond and a photopolymerization initiation system, and optionally a binder resin, and by scanning exposure, the photoinitiation system absorbs light, An active species such as an active radical is generated to cause and advance the polymerization reaction of the polymerizable compound, thereby curing the exposed area to form an image.
In such a photosensitive composition capable of scanning exposure, various photoinitiating systems with excellent photosensitivity have been disclosed (for example, see Non-Patent Documents 1 and 2). The photoinitiating system described in these documents is a light source when applied to a conventional CTP system using a long wavelength visible light source such as an Ar laser (488 nm) or an FD-YAG laser (532 nm) as an exposure light source. In the present situation where the output is not sufficiently high, sufficient sensitivity cannot be obtained, and a highly sensitive starting system that can be adapted to further high-speed exposure is desired.

On the other hand, in recent years, for example, semiconductor lasers that use InGaN-based materials and can continuously oscillate in the 350 nm to 450 nm region have been put into practical use. The scanning exposure system using these short-wave light sources has an advantage that an economical system can be constructed while having a sufficient output because a semiconductor laser can be manufactured at a low cost because of its structure. Furthermore, as compared with a system using a conventional FD-YAG or Ar laser, a photosensitive material having photosensitivity in a short wavelength region capable of working under a brighter safe light can be used. However, there is currently no known photoinitiating system having sufficient sensitivity for scanning exposure in such a short wavelength region of 350 nm to 450 nm.
In response, a photosensitive composition containing a sensitizing dye, a hexaarylbiimidazole compound, and a mercapto compound that are highly sensitive in this short wavelength region has been proposed (for example, see Patent Documents 1 and 2).

In addition, as a common problem to all image forming materials containing these photosensitive compositions, the problem of how to enlarge the ON / OFF of the image in the laser light irradiated portion and the unirradiated portion, that is, the image forming material There is a problem of achieving both high sensitivity and storage stability. Usually, the radical photopolymerization system is highly sensitive, but the sensitivity is greatly lowered due to polymerization inhibition by oxygen in the air. Therefore, means for providing an oxygen barrier layer on the image forming layer is taken. However, when an oxygen-blocking layer is provided, fogging due to dark polymerization or the like occurs, and storage stability deteriorates. Also, when the photoinitiating material in the photosensitive layer decomposes and disappears under storage conditions, the amount of active radicals generated by light irradiation is reduced, which is one of the causes of storage stability deterioration. Accordingly, it is difficult to achieve both high sensitivity and storage stability, and a photosensitive composition containing the above-described high-sensitivity sensitizing dye, hexaarylbiimidazole compound, and mercapto compound (see, for example, Patent Documents 1 and 2). Thus, it cannot be said that both high sensitivity and storage stability are sufficiently achieved. As described above, a sufficiently satisfactory result has not been obtained with the conventional technique, and a new technique that has not been conventionally required has been demanded.
JP 2004-191938 A JP 2004-295058 A Bruce M. Monroe et al., Chemical Revue, 93, (1993), p. 435-p.448 RS Davidson, Journal of Photochemistry and Biology A: Chemistry, Vol. 73, (1993), p. 81-p. 96

  The object of the present invention in consideration of the above problems is high sensitivity to an oscillation wavelength of 350 nm to 450 nm of an inexpensive short-wave semiconductor laser, and excellent storage stability, workability, economy, printing durability, and stain resistance. To provide a photosensitive composition using a novel photoinitiating system useful as a photosensitive layer of a photosensitive lithographic printing plate for scanning exposure that is compatible with, for example, a CTP system, and an image recording method using the same is there.

As a result of intensive studies to achieve the above object, the present inventors have found that a novel photoinitiating system comprising a mercapto compound having a specific structure, a hexaarylbiimidazole compound, and a sensitizing dye has high photosensitivity. In particular, the inventors have found that the film has high sensitivity especially in the vicinity of 350 nm to 450 nm and is excellent in storage stability, and the present invention has been completed.
That is, the present invention is as follows.

(1) (A) a mercapto compound represented by the following general formula (I) and having a volume of 215 ³ or more,
A-SH (I)
(In general formula (I), A represents a heterocyclic compound which may have a substituent.)
(B) a hexaarylbiimidazole compound,
(C) a sensitizing dye, and (D) a polymerizable compound having an ethylenically unsaturated double bond,
A photosensitive composition comprising:

Here, the volume of the mercapto compound of the present invention is a parameter expressed by electron density, and is calculated using a molecular orbital method. The molecular orbital method used in the present invention is calculated by solving the Hartree-Fock-Roothaan equation FC = SCE (F: Hartree-Fock matrix, C: AO coefficient matrix, S: overlap integral, E: energy eigenvalue physics matrix). However, “MOPAC”, which is generally a semi-empirical molecular orbital method, is used.
"MOPAC" ignores the differential overlap of two-electron integrals, and further reduces the computational complexity by using parameters (eg PM3 parameters) instead of integral calculations for experimental values of atoms and some typical molecules Is a calculation method widely known in the art.
The PM3 parameter refers to the generation heat, structure, ionization potential, and dipole moment data of 763 molecules, and H, C, N, O, F, Al, Si, P, S, Cl, Br, This is a parameter used when solving the semi-empirical molecular orbital method in which 12 parameters of I are determined at once by the least square method. This parameter is explained in detail in the Chemical Society of Japan, Experimental Chemistry Course (5th edition) 12 Computational Chemistry, Maruzen, p.48-59.

(2) The photosensitive composition as described in (1) above, wherein A in the mercapto compound represented by the general formula (I) is a nitrogen-containing five-membered ring.
(3) An image characterized by performing scanning exposure on an image recording material having a photosensitive layer containing the photosensitive composition described in (1) above on a support using a 350 to 430 nm laser light source. Recording method.
(4) A photosensitive lithographic printing plate having a support and a photosensitive layer containing the photosensitive composition described in (1) above.

The effect | action of this invention is estimated as follows.
First, a sensitizing dye is highly sensitive to an irradiation (exposure) of a specific wavelength and is in an electronically excited state. The hexaarylbiimidazole compound in which electron transfer, energy transfer, heat generation, etc. associated with the electron excited state due to light absorption coexist is present. Acts on the hexaarylbiimidazole compound to cause a chemical change to generate a radical. Furthermore, the radicals generated here extract hydrogen from a hydrogen donor, such as a mercapto compound, and the S radicals generated therefrom cause irreversible changes such as coloring, decoloring, and polymerization in the reactive polymerizable compound. Let By using an addition polymerizable compound having an ethylenically unsaturated double bond, which is preferable among these compounds, the curing reaction starts and proceeds, and the exposed region is cured. Therefore, the active species in the main curing reaction is considered to be due to the mercapto compound.

Further, the mercapto compound having a volume of 215 ³ or more according to the present invention is more sensitive than the conventionally used mercaptobenzothiazole, mercaptobenzoxazole, mercaptobenzimidazole, etc. It is considered that mobility (motility) is lowered. Therefore, it is considered that the storage stability of the photosensitive composition has been improved by using the photosensitive composition of the present invention.

  According to the present invention, for example, a CTP system that is highly sensitive to an oscillation wavelength of 350 nm to 450 nm of an inexpensive shortwave semiconductor laser and excellent in workability, economy, printing durability, stain resistance, and storage stability. And a photosensitive composition useful as a photosensitive layer for a photosensitive lithographic printing plate for scanning exposure, and an image recording method using the same.

Hereinafter, the present invention will be described in detail.
The photosensitive composition of the present invention comprises (A) a mercapto compound represented by the general formula (I), (B) a hexaarylbiimidazole compound, (C) a sensitizing dye, (D) an ethylenically unsaturated double bond. It contains the polymerizable compound which has this. Below, each compound which can be used for the photosensitive composition of this invention is demonstrated one by one.

(A) Mercapto compound represented by general formula (I) A in general formula (I) is a heterocyclic compound which may have a monovalent substituent, and the heterocyclic groups are N, S And a compound having at least one 5-membered ring containing at least one of O and this heterocyclic group may contain a condensed ring. Examples of preferred aromatic heterocyclic groups include, for example, thiophene, thiathrene, furan, pyran, isobenzofuran, chromene, xanthene, phenoxazine, pyrrole, pyrazole, isothiazole, isoxazole, pyrazine, pyrimidine, pyridazine, indolizine, Indolizine, indoir, indazole, purine, quinolidine, isoquinoline, phthalazine, naphthyridine, quinazoline, sinoline, pteridine, carbazole, carboline, phenanthrine, acridine, perimidine, phenanthrolin, phthalazine, phenazazine, phenoxazine, furazane, phenoxazine, etc. These may be further benzo-fused or may have a substituent. Examples of monovalent substituents include halogen atoms, amino groups, substituted amino groups, substituted carbonyl tombs, hydroxyl groups, substituted oxy groups, silyl groups, nitro groups, cyano groups, alkyl groups, alkenyl groups, aryl groups, and heterocyclic rings. Group, sulfo group, substituted sulfonyl group, sulfonate group, substituted sulfinyl group, phosphono group, substituted phosphono group, phosphonate group, substituted phosphonate group, and the like. Good.

  Examples of the alkyl group include linear, branched or cyclic alkyl groups having 1 to 20 carbon atoms. Among these, a linear alkyl group having 1 to 20 carbon atoms, a branched alkyl group having 5 to 20 carbon atoms, and a cyclic alkyl group having 5 to 20 carbon atoms are more preferable. Specific examples thereof include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, hexadecyl group, octadecyl group. , Eicosyl group, isopropyl group, isobutyl group, s-butyl group, t-butyl group, isopentyl group, neopentyl group, 1-methylbutyl group, isohexyl group, 2-ethylhexyl group, 2-methylhexyl group, cyclohexyl group, cyclopentyl group , 2-norbornyl group, and adamantyl group.

  When the alkyl group has a substituent (ie, when it is a substituted alkyl group), the alkyl part of the substituted alkyl group includes any one of the hydrogen atoms on the alkyl group having 1 to 20 carbon atoms described above. In addition, a divalent organic residue can be exemplified, and a preferable range of the number of carbon atoms is the same as that of the alkyl group.

  Preferred examples of the substituted alkyl group include a chloromethyl group, a bromomethyl group, a 2-chloroethyl group, a trifluoromethyl group, a methoxymethyl group, a methoxycarbonylmethyl group, an isopropoxymethyl group, a butoxymethyl group, s -Butoxybutyl, methoxyethoxyethyl, allyloxymethyl, phenoxymethyl, acetyloxymethyl, methylthiomethyl, tolylthiomethyl, pyridylmethyl, tetramethylpiperidinylmethyl, N-acetyltetramethyl Piperidinylmethyl group, trimethylsilylmethyl group, methoxyethyl group, ethylaminoethyl group, diethylaminopropyl group, morpholinopropyl group, acetyloxymethyl group, benzoyloxymethyl group, N-cyclohexylcarbamoyloxy Til group, N-phenylcarbamoyloxyethyl group, acetylaminoethyl group, N-methylbenzoylaminopropyl group, 2-oxoethyl group, 2-oxopropyl group, carboxypropyl group, methoxycarbonylethyl group, allyloxycarbonylbutyl group, Chlorophenoxycarbonylmethyl group, carbamoylmethyl group, N-methylcarbamoylethyl group, N, N-dipropylcarbamoylmethyl group, N- (methoxyphenyl) carbamoylethyl group, N-methyl-N- (sulfophenyl) carbamoylmethyl group , Sulfobutyl group, sulfonatobutyl group, sulfamoylbutyl group, N-ethylsulfamoylmethyl group, N, N-dipropylsulfamoylpropyl group, N-tolylsulfamoylpropyl group, N-methyl-N- (phospho Phenyl) sulfamoyloctyl, phosphonobutyl, phosphonatohexyl, diethylphosphonobutyl, diphenylphosphonopropyl, methylphosphonobutyl, methylphosphonatobutyl, tolylphosphonohexyl, tolylphosphonatohexyl Group, phosphonooxypropyl group, phosphonatoxybutyl group, benzyl group, phenethyl group, α-methylbenzyl group, 1-methyl-1-phenylethyl group, p-methylbenzyl group, cinnamyl group, allyl group, 1- Examples thereof include a propenylmethyl group, a 2-butenyl group, a 2-methylallyl group, a 2-methylpropenylmethyl group, a 2-propynyl group, a 2-butynyl group, and a 3-butynyl group. Among these, a phenethyl group, a 1-methyl-1-phenylethyl group, a p-methylbenzyl group, and a cinnamyl group are particularly preferable.

Examples of the substituent that can be introduced into the alkyl group include monovalent substituents composed of the nonmetallic atoms exemplified below in addition to the substituents described in the description of the substituted alkyl group. Preferred examples including the above-described substituent include a halogen atom (—F, —Br, —Cl, —I), hydroxyl group, alkoxy group, aryloxy group, mercapto group, alkylthio group, arylthio group, alkyldithio group, aryl. Dithio group, amino group, N-alkylamino group, N, N-dialkylamino group, N-arylamino group, N, N-diarylamino group, N-alkyl-N-arylamino group, acyloxy group, carbamoyloxy group N-alkylcarbamoyloxy group, N-arylcarbamoyloxy group, N, N-dialkylcarbamoyloxy group, N, N-diarylcarbamoyloxy group, N-alkyl-N-arylcarbamoyloxy group, alkylsulfoxy group, aryl Sulfoxy group, acylthio group, acylamino group, -Alkylacylamino group, N-arylacylamino group, ureido group, N'-alkylureido group, N ', N'-dialkylureido group, N'-arylureido group, N', N'-diarylureido group, N′-alkyl-N′-arylureido group, N-alkylureido group, N-arylureido group, N′-alkyl-N-alkylureido group, N′-alkyl-N-arylureido group, N ′, N '-Dialkyl-N-alkylureido group, N', N'-dialkyl-N-arylureido group, N'-aryl-N-alkylureido group, N'-aryl-N-arylureido group, N ', N '-Diaryl-N-alkylureido group, N', N'-diaryl-N-arylureido group, N'-alkyl-N'-aryl-N-alkylureido group, N'-alkyl Ru-N′-aryl-N-arylureido group, alkoxycarbonylamino group, aryloxycarbonylamino group, N-alkyl-N-alkoxycarbonylamino group, N-alkyl-N-aryloxycarbonylamino group, N-aryl -N-alkoxycarbonylamino group, N-aryl-N-aryloxycarbonylamino group, formyl group, acyl group, carboxyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, N-alkylcarbamoyl group, N, N -Dialkylcarbamoyl group, N-arylcarbamoyl group, N, N-diarylcarbamoyl group, N-alkyl-N-arylcarbamoyl group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, sulfo Fo group (—SO ₃ H) and its conjugate base group (referred to as sulfonate group), alkoxysulfonyl group, aryloxysulfonyl group, sulfinamoyl group, N-alkylsulfinamoyl group, N, N-dialkylsulfinamoyl group, N-arylsulfinamoyl group, N, N-diarylsulfinamoyl group, N-alkyl-N-arylsulfinamoyl group, sulfamoyl group, N-alkylsulfamoyl group, N, N-dialkylsulfamoyl group N-arylsulfamoyl group, N, N-diarylsulfamoyl group, N-alkyl-N-arylsulfamoyl group, phosphono group (—PO ₃ H ₂ ) and its conjugate base group (referred to as phosphonato group) . ), Dialkylphosphono group (—PO ₃ (alkyl) ₂ ) “alkyl = alkyl group, hereinafter the same”, diarylphosphono group (—PO ₃ (aryl) ₂ ) “aryl = aryl group, hereinafter the same”, alkylaryl A phosphono group (—PO ₃ (alkyl) (aryl)), a monoalkylphosphono group (—PO ₃ (alkyl)) and its conjugate base group (referred to as alkylphosphonate group), a monoarylphosphono group (— PO ₃ H (aryl)) and its conjugate base group (referred to as arylphosphonate group), phosphonooxy group (—OPO ₃ H ₂ ) and its conjugate base group (referred to as phosphonatoxy group), dialkylphosphonooxy group (— _{OPO 3 H (alkyl) 2)} , diaryl phosphono group _{(-OPO 3 (aryl) 2)} , alkylaryl phosphonooxymethyl (-OPO ₃ (alkyl) (aryl)), monoalkyl phosphono group (-OPO ₃ H (alkyl)) and its conjugated base group (referred to as alkylphosphonato group.), Monoarylphosphono group ( -OPO ₃ H (aryl)) and its conjugate base group (referred to as arylphosphonatoxy group), cyano group, nitro group, aryl group, alkenyl group, alkynyl group, heterocyclic group, silyl group, and the like. .

Specific examples of the alkyl moiety in the substituent that can be introduced into the alkyl group are the same as in the case where the monovalent substituent described above is a substituted alkyl group, and the preferred range is also the same.
Specific examples of the aryl moiety in the substituent that can be introduced into the alkyl group represented by the monovalent substituent include phenyl, biphenyl, naphthyl, tolyl, xylyl, mesityl, cumenyl, and chlorophenyl. Group, bromophenyl group, chloromethylphenyl group, hydroxyphenyl group, methoxyphenyl group, ethoxyphenyl group, phenoxyphenyl group, acetoxyphenyl group, benzoyloxyphenyl group, methylthiophenyl group, phenylthiophenyl group, methylaminophenyl group Dimethylaminophenyl group, acetylaminophenyl group, carboxyphenyl group, methoxycarbonylphenyl group, ethoxyphenylcarbonyl group, phenoxycarbonylphenyl group, N-phenylcarbamoylphenyl group, cyanophenyl group, sulfo Eniru group, a sulfophenyl group, phosphono phenyl group, phosphonium Hona preparative phenyl group, and the like.

  Examples of the alkenyl group include alkenyl groups having 2 to 20 carbon atoms. Among these, an alkenyl group having 2 to 10 carbon atoms is preferable, and an alkenyl group having 2 to 8 carbon atoms is more preferable. The alkenyl group may further have a substituent. Examples of the substituent that can be introduced include a halogen atom, an alkyl group, a substituted alkyl group, an aryl group, and a substituted aryl group. The halogen atom is a straight chain or branched chain having 1 to 10 carbon atoms. A cyclic alkyl group is preferred. Specific examples of the alkenyl group include, for example, vinyl group, 1-propenyl group, 1-butenyl group, cinnamyl group, 1-pentenyl group, 1-hexenyl group, 1-octenyl group, 1-methyl-1-propenyl group, A 2-methyl-1-propenyl group, a 2-methyl-1-butenyl group, a 2-phenyl-1-ethenyl group, a 2-chloro-1-ethenyl group, and the like can be given.

  Examples of the alkynyl group include alkynyl groups having 2 to 20 carbon atoms. Among these, an alkynyl group having 2 to 10 carbon atoms is preferable, and an alkynyl group having 2 to 8 carbon atoms is more preferable. Specific examples thereof include ethynyl group, 1-propynyl group, 1-butynyl group, phenylethynyl group, trimethylsilylethynyl group and the like.

  Examples of the aryl group include a benzene ring, a group in which 2 to 3 benzene rings form a condensed ring, and a group in which a benzene ring and a 5-membered unsaturated ring form a condensed ring. Specific examples thereof include a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, an indenyl group, an acenaphthenyl group, and a fluorenyl group. Among these, a phenyl group and a naphthyl group are more preferable.

  When the aryl group has a substituent (that is, when it is a substituted aryl group), the substituted aryl group has a monovalent substituent composed of a nonmetallic atom as a substituent on a ring-forming carbon atom. Is mentioned. Preferable examples of the substituent to be introduced include those described above in the description of the alkyl group, the substituted alkyl group, and the substituent in the substituted alkyl group.

  Preferred examples of the substituted aryl group include a biphenyl group, a tolyl group, a xylyl group, a mesityl group, a cumenyl group, a chlorophenyl group, a bromophenyl group, a fluorophenyl group, a chloromethylphenyl group, a trifluoromethylphenyl group, Hydroxyphenyl group, methoxyphenyl group, methoxyethoxyphenyl group, allyloxyphenyl group, phenoxyphenyl group, methylthiophenyl group, tolylthiophenyl group, ethylaminophenyl group, diethylaminophenyl group, morpholinophenyl group, acetyloxyphenyl group, benzoyl Oxyphenyl group, N-cyclohexylcarbamoyloxyphenyl group, N-phenylcarbamoyloxyphenyl group, acetylaminophenyl group, N-methylbenzoylaminophenyl group, carbo Cyphenyl group, methoxycarbonylphenyl group, allyloxycarbonylphenyl group, chlorophenoxycarbonylphenyl group, carbamoylphenyl group, N-methylcarbamoylphenyl group, N, N-dipropylcarbamoylphenyl group, N- (methoxyphenyl) carbamoylphenyl group N-methyl-N- (sulfophenyl) carbamoylphenyl group, sulfophenyl group, sulfonatophenyl group, sulfamoylphenyl group, N-ethylsulfamoylphenyl group, N, N-dipropylsulfamoylphenyl group, N-tolylsulfamoylphenyl group, N-methyl-N- (phosphonophenyl) sulfamoylphenyl group, phosphonophenyl group, phosphonatophenyl group, diethylphosphonophenyl group, diphenylphosphonophenyl group Methylphosphonophenyl group, methylphosphonatophenyl group, tolylphosphonophenyl group, tolylphosphonophenyl group, allylphenyl group, 1-propenylmethylphenyl group, 2-butenylphenyl group, 2-methylallylphenyl group, 2 -Methylpropenylphenyl group, 2-propynylphenyl group, 2-butynylphenyl group, 3-butynylphenyl group and the like can be mentioned. Among these, a biphenyl group, a tolyl group, a xylyl group, a mesityl group, a chlorophenyl group and the like are preferable.

  The heterocyclic group is preferably a 3- to 8-membered heterocyclic group, more preferably a 3- to 6-membered heterocyclic group containing a nitrogen atom, an oxygen atom or a sulfur atom, a nitrogen atom, an oxygen atom or sulfur. A 5- to 6-membered heterocyclic group containing an atom is more preferable. Specific examples thereof include a pyridyl group and a piperidinyl group.

  The silyl group may have a substituent, is preferably a silyl group having 0 to 30 carbon atoms, more preferably a silyl group having 3 to 20 carbon atoms, and further preferably a silyl group having 3 to 10 carbon atoms. Specific examples thereof include a trimethylsilyl group, a triethylsilylyl group, a tripropylsilyl group, a triisopropylsilyl group, a cyclohexyldimethylsilyl group, and a dimethylvinylsilyl group.

  Examples of the halogen atom include a fluorine atom, a bromine atom, a chlorine atom, and an iodine atom. Among these, a chlorine atom and a bromine atom are preferable.

The substituted oxy group (R ⁰⁶ O-), can be used a group R ⁰⁶ is a monovalent nonmetallic atom group exclusive of a hydrogen atom. Preferred substituted oxy groups include alkoxy groups, aryloxy groups, acyloxy groups, carbamoyloxy groups, N-alkylcarbamoyloxy groups, N-arylcarbamoyloxy groups, N, N-dialkylcarbamoyloxy groups, N, N-diarylcarbamoyloxy groups. Groups, N-alkyl-N-arylcarbamoyloxy groups, alkylsulfoxy groups, arylsulfoxy groups, phosphonooxy groups, and phosphonatoxy groups. Examples of the alkyl group and aryl group in these include the alkyl groups, substituted alkyl groups, aryl groups, and substituted aryl groups described above. Examples of the acyl group (R ⁰⁷ CO—) in the acyloxy group include those in which R ⁰⁷ is an alkyl group, a substituted alkyl group, an aryl group, or a substituted aryl group mentioned as the previous example. Among these substituents, an alkoxy group, an aryloxy group, an acyloxy group, and an arylsulfoxy group are more preferable. Specific examples of preferred substituted oxy groups include methoxy, ethoxy, propyloxy, isopropyloxy, butyloxy, pentyloxy, hexyloxy, dodecyloxy, benzyloxy, allyloxy, phenethyloxy, Carboxyethyloxy group, methoxycarbonylethyloxy group, ethoxycarbonylethyloxy group, methoxyethoxy group, phenoxyethoxy group, methoxyethoxyethoxy group, ethoxyethoxyethoxy group, morpholinoethoxy group, morpholinopropyloxy group, allyloxyethoxyethoxy group, Phenoxy, tolyloxy, xylyloxy, mesityloxy, cumenyloxy, methoxyphenyloxy, ethoxyphenyloxy, chlorophenyloxy, bromo Niruokishi group, acetyloxy group, benzoyloxy group, naphthyloxy group, a phenylsulfonyloxy group, a phosphonooxy group, phosphonatoxy group.

The amino group may be a substituted amino group including an amide group. The substituted amino group (R ⁰⁸ NH—, (R ⁰⁹ ) (R ⁰¹⁰ ) N—) including an amide group is a group in which R ⁰⁸ , R ⁰⁹ , and R ⁰¹⁰ are monovalent nonmetallic atomic groups excluding hydrogen atoms Can be used. R ⁰⁹ and R ⁰¹⁰ may combine to form a ring. Preferred examples of the substituted amino group include an N-alkylamino group, an N, N-dialkylamino group, an N-arylamino group, an N, N-diarylamino group, an N-alkyl-N-arylamino group, an acylamino group, N-alkylacylamino group, N-arylacylamino group, ureido group, N′-alkylureido group, N ′, N′-dialkylureido group, N′-arylureido group, N ′, N′-diarylureido group N′-alkyl-N′-arylureido group, N-alkylureido group, N-arylureido group, N′-alkyl-N-alkylureido group, N′-alkyl-N-arylureido group, N ′, N′-dialkyl-N-alkylureido group, N′-alkyl-N′-arylureido group, N ′, N′-dialkyl-N-alkylureido group, N ′, '-Dialkyl-N'-arylureido group, N'-aryl-N-alkylureido group, N'-aryl-N-arylureido group, N', N'-diaryl-N-alkylureido group, N ', N′-diaryl-N-arylureido group, N′-alkyl-N′-aryl-N-alkylureido group, N′-alkyl-N′-aryl-N-arylureido group, alkoxycarbonylamino group, aryloxy A carbonylamino group, an N-alkyl-N-alkoxycarbonylamino group, an N-alkyl-N-aryloxycarbonylamino group, an N-aryl-N-alkoxycarbonylamino group, and an N-aryl-N-aryloxycarbonylamino group. Can be mentioned. Examples of the alkyl group and aryl group include those described above as the alkyl group, substituted alkyl group, aryl group, and substituted aryl group, such as acylamino group, N-alkylacylamino group, and N-arylacylamino. R ⁰⁷ groups definitive acyl group (R ⁰⁷ CO-) are as described above. Of these, more preferred are an N-alkylamino group, an N, N-dialkylamino group, an N-arylamino group, and an acylamino group. Specific examples of preferred substituted amino groups include methylamino group, ethylamino group, diethylamino group, morpholino group, piperidino group, pyrrolidino group, phenylamino group, benzoylamino group, acetylamino group and the like.

As the substituted sulfonyl group (R ⁰¹¹ —SO ₂ —), those in which R ⁰¹¹ is a group composed of a monovalent nonmetallic atomic group can be used. More preferable examples include an alkylsulfonyl group, an arylsulfonyl group, and a substituted or unsubstituted sulfamoyl group. Examples of the alkyl group and aryl group in these include those described above as the alkyl group, substituted alkyl group, aryl group, and substituted aryl group. Specific examples of such a substituted sulfonyl group include butylsulfonyl group, phenylsulfonyl group, chlorophenylsulfonyl group, sulfamoyl group, N-alkylsulfamoyl group, N, N-dialkylsulfamoyl group, N-arylsulfuryl group. A famoyl group, an N-alkyl-N-arylsulfamoyl group, and the like.

As described above, the sulfonate group (—SO ₃ —) means a conjugate base anion group of the sulfo group (—SO ₃ H), and is usually preferably used together with a counter cation. Examples of such counter cations include those generally known, that is, various oniums (ammonium compounds, sulfonium compounds, phosphonium compounds, iodonium compounds, azinium compounds, etc.), and metal ions (Na ⁺ , K ⁺ , Ca). ²⁺ , Zn ^2+, etc.).

As the substituted carbonyl group (R ⁰¹³ —CO—), those in which R ⁰¹³ is a group composed of a monovalent nonmetallic atomic group can be used. Preferred examples of the substituted carbonyl group include formyl group, acyl group, carboxyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, N-alkylcarbamoyl group, N, N-dialkylcarbamoyl group, N-arylcarbamoyl group, N, N-diarylcarbamoyl group, N-alkyl-N′-arylcarbamoyl group may be mentioned. Examples of the alkyl group and aryl group in these include those described above as the alkyl group, substituted alkyl group, aryl group, and substituted aryl group. Among these, more preferred substituted carbonyl groups include formyl, acyl, carboxyl, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, N-alkylcarbamoyl, N, N-dialkylcarbamoyl, N-ary. A rucarbamoyl group can be mentioned, and even more preferred are a formyl group, an acyl group, an alkoxycarbonyl group and an aryloxycarbonyl group. Specific examples of preferred substituted carbonyl groups include formyl group, acetyl group, benzoyl group, carboxyl group, methoxycarbonyl group, ethoxycarbonyl group, allyloxycarbonyl group, dimethylaminophenylethenylcarbonyl group, methoxycarbonylmethoxycarbonyl group, N -Methylcarbamoyl group, N-phenylcarbamoyl group, N, N-diethylcarbamoyl group, morpholinocarbonyl group and the like.

As the substituted sulfinyl group (R ⁰¹⁴ —SO—), a group in which R ⁰¹⁴ is a monovalent nonmetallic atomic group can be used. Preferable examples include alkylsulfinyl group, arylsulfinyl group, sulfinamoyl group, N-alkylsulfinamoyl group, N, N-dialkylsulfinamoyl group, N-arylsulfinamoyl group, N, N-diarylsulfinamoyl. Group, N-alkyl-N-arylsulfinamoyl group. Examples of the alkyl group and aryl group in these include those described above as the alkyl group, substituted alkyl group, aryl group, and substituted aryl group. Of these, more preferred examples include an alkylsulfinyl group and an arylsulfinyl group. Specific examples of such a substituted sulfinyl group include a hexylsulfinyl group, a benzylsulfinyl group, and a tolylsulfinyl group.

  The substituted phosphono group means a group in which one or two hydroxyl groups on the phosphono group are substituted with other organic oxo groups, and preferred examples thereof include the above-mentioned dialkylphosphono group, diarylphosphono group, alkylarylphospho group. Group, monoalkylphosphono group and monoarylphosphono group. Of these, dialkylphosphono groups and diarylphosphono groups are more preferred. Specific examples thereof include a diethyl phosphono group, a dibutyl phosphono group, a diphenyl phosphono group, and the like.

Phosphonato group _{(-PO 3 H 2 -, -} PO 3 H-) and the meaning of a phosphono group (-PO ₃ H _2), first dissociation or acid, a conjugated base anion group derived from the second dissociation acid To do. Usually, it is preferable to use it with a counter cation. Such counter cations include those generally known, that is, various oniums (ammonium, sulfonium, phosphonium, iodonium, azinium, etc.) and metal ions (Na ⁺ , K ⁺ , Ca ²⁺ , Zn ²⁺ etc.).

The substituted phosphonato group is a conjugated base anion group obtained by substituting one organic oxo group in the above-described substituted phosphono group. As a specific example, the above-described monoalkylphosphono group (—PO ₃ H ( alkyl)), and a conjugate base of a monoarylphosphono group (—PO ₃ H (aryl)).

Next, as a preferred embodiment of (A), A (heterocyclic group) is, as described above, a 5-membered ring or more, preferably a 5-membered heterocyclic ring containing at least one of N, S and O. Group, and this heterocyclic group may contain a condensed ring. The volume of the mercapto compound represented by the general formula (I) is 215 ³ or more, preferably 250 ³ or more, more preferably 300 ³ or more.
Preferable examples in terms of sensitivity and storage stability include those having the following structures.

Here, the substituents R ^{1 to} R ¹² are the same as the monovalent substituent described above, and R ² and R ³ , R ⁴ and R ⁵ , R ⁶ and R ⁷ , and R ⁸ and R ⁹ are each a condensed ring. May be formed.

Specific examples of the compound represented by the general formula (I) [Exemplary compounds (A-1) to (A-69)] are listed below, but the scope of the present invention is not limited thereto. The volume (Å ³ ) in each exemplified compound is also shown.

(Evaluation of substituent volume)
The volume of the general formula (I) A-SH given in the specific example below is the volume of the electron density after optimizing the structure with the MOPAC PM3 parameter using the Cache system (Fujitsu, Computer Aided Chemistry Ver.5.5). Each volume was obtained using (calculation) and indicated by these values.

  A in the general formula (I) is a heterocyclic compound which may have a substituent. Furthermore, A in the mercapto compound represented by the general formula (I) preferably contains a nitrogen-containing five-membered ring.

  Next, as a typical synthesis example of the compound represented by the general formula (I), a synthesis example of the above-described exemplary compound (A-19) is shown, but the present invention is not limited thereto. Moreover, it can synthesize | combine similarly about another exemplary compound.

<Synthesis Example of Exemplary Compound (A-19)>
Synthesis of (A-19 Precursor) 1000 mL of acetonitrile was added to a 2 L three-necked flask, and 49 g of benzoylhydrazine was added. While stirring the reaction solution, 58 g of phenethyl isothiocyanate was added over 15 minutes, and the mixture was stirred for 30 minutes while heating at 40 ° C. After cooling the reaction solution, the precipitated white powder was collected by filtration to obtain 75 g of (A-19 precursor). It was confirmed from the NMR spectrum, IR spectrum, and mass spectrometry spectrum that it was the target product.

Synthesis of (A-19) To a 1 L eggplant-shaped flask, 250 g of water and 25 g of sodium hydroxide were added and stirred at room temperature. 75 g of the above-mentioned (A-9 precursor) was added to this aqueous sodium hydroxide solution, and the mixture was stirred for 1 hour while heating at 100 ° C. After cooling the reaction solution, concentrated hydrochloric acid was added to adjust the pH to 7, and the precipitated white solid was collected by filtration of the reaction solution to obtain 70 g of (A-19).

  The content of the compound represented by the general formula (I) in the present invention is the same when applied to a recording layer (photosensitive layer) of an image recording material such as a photosensitive lithographic printing plate. The total solid content contained in the composition is preferably 0.01 to 50% by mass, more preferably 0.01 to 30% by mass, and still more preferably 0.1 to 20% by mass.

(B) Hexaarylbiimidazole compound The hexaarylbiimidazole compound used in the present invention is excellent in stability and capable of highly sensitive radical generation.
As the hexaarylbisimidazole compound, various compounds described in EP24629, EP107792, US4410621, EP215453, DE32111312 and the like can be used.
Preferable specific examples of the hexaarylbiimidazole compound include 2,2′-bis (o-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole and 2,2′-bis (o-bromophenyl). ) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (o, p-dichlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2 ′ -Bis (o-chlorophenyl) -4,4 ', 5,5'-tetra (m-methoxyphenyl) biimidazole, 2,2'-bis (o, o'-dichlorophenyl) -4,4', 5 5′-tetraphenylbiimidazole, 2,2′-bis (o-nitrophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (o-methylphenyl) -4 , 4 ', 5,5'-Tetraphenylbiimi Examples include dazole, 2,2′-bis (o-trifluoromethylphenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, and the like.

(C) Sensitizing dye In the present invention, it is preferable to add a sensitizing dye that absorbs light of a predetermined wavelength. Exposure to a wavelength that can be absorbed by the sensitizing dye promotes the radical generating reaction of the component (B) and the polymerization reaction of the component (D) described later. Examples of the sensitizing dye (C) include known spectral sensitizing dyes or dyes, or dyes or pigments that absorb light and interact with a photopolymerization initiator. Depending on the wavelength of light absorbed by the sensitizing dye, the photosensitive composition of the present invention can be sensitive to various wavelengths from ultraviolet rays to visible rays and infrared rays. For example, when an infrared absorber is used as (C) the sensitizing dye, it is sensitive to infrared light having a wavelength of 760 nm to 1200 nm. In addition, by using a pigment having a maximum absorption wavelength from 350 nm to 450 nm, it is sensitive to blue to purple visible light.

(Spectral sensitizing dye or dye)
Spectral sensitizing dyes or dyes preferable as (C) sensitizing dyes used in the present invention are polynuclear aromatics (for example, pyrene, perylene, triphenylene), xanthenes (for example, fluorescein, eosin, erythrosine, rhodamine B). , Rose bengal), cyanines (eg thiacarbocyanine, oxacarbocyanine), merocyanines (eg merocyanine, carbomerocyanine), thiazines (eg thionine, methylene blue, toluidine blue), acridines (eg acridine orange) , Chloroflavin, acriflavine), phthalocyanines (eg, phthalocyanine, metal phthalocyanine), porphyrins (eg, tetraphenylporphyrin, central metal-substituted porphyrin), chlorophylls (eg, chloro I le, chlorophyllin, center metal-substituted chlorophyll), metal complexes (for example, the following compound), anthraquinones, such as (anthraquinone), squaryliums, for example (squarylium), and the like.

The example of a more preferable spectral sensitizing dye or dye is illustrated below.
A styryl dye described in JP-B-37-13034; a cationic dye described in JP-A-62-143044; a quinoxalinium salt described in JP-B-59-24147; described in JP-A-64-33104 A new methylene blue compound; anthraquinones described in JP-A 64-56767; benzoxanthene dyes described in JP-A-2-17714; acridines described in JP-A-2-226148 and JP-A-2-226149 Pyryllium salts described in JP-B-40-28499; Cyanines described in JP-B-46-42363; Benzofuran dyes described in JP-A-2-63053; JP-A-2-85858, JP-A-2-216154 Conjugated ketone dyes; dyes described in JP-A-57-1605; Azocinnamylidene derivatives described in Japanese Patent No. 0321; cyanine dyes described in Japanese Patent Laid-Open No. 1-287105; Japanese Patent Laid-Open Nos. 62-31844, 62-31848, 62-1443043 Xanthene dyes described above; aminostyryl ketone described in JP-B-59-28325; dye described in JP-A-2-17943; merocyanine dye described in JP-A-2-244050; described in JP-B-59-28326 Merocyanine dyes described in JP-A-59-89303; merocyanine dyes described in JP-A-8-129257; benzopyran dyes described in JP-A-8-334897.

(Infrared absorber)
In addition, the following infrared absorbers (dyes or pigments) are particularly preferably used as the sensitizing dye (C).
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.
Preferred dyes include, for example, cyanine dyes described in JP-A-58-125246, JP-A-59-84356, JP-A-59-202829, JP-A-60-78787, and the like. Methine dyes described in JP-A-58-173696, JP-A-58-181690, JP-A-58-194595, JP-A-58-112793, JP-A-58-224793, JP-A-59- 48187, JP-A-59-73996, JP-A-60-52940, JP-A-60-63744, etc., naphthoquinone dyes, JP-A-58-112792, etc. And cyanine dyes described in British Patent 434,875.

Also, a near infrared absorption sensitizer described in US Pat. No. 5,156,938 is preferably used, and a substituted arylbenzo (thio) pyrylium salt described in US Pat. No. 3,881,924, Trimethine thiapyrylium salts described in JP-A-57-142645 (US Pat. No. 4,327,169), JP-A-58-181051, 58-220143, 59-41363, 59-84248 Nos. 59-84249, 59-146063, 59-146061, pyranlium compounds, cyanine dyes described in JP-A-59-216146, US Pat. No. 4,283,475 The pentamethine thiopyrylium salts described above and the pyrylium compounds disclosed in Japanese Patent Publication Nos. 5-13514 and 5-19702 are also preferably used. . Moreover, as another example preferable as a dye, the near-infrared absorptive dye described as the formula (I) and (II) in US Patent 4,756,993 can be mentioned.
Other preferable examples of the infrared absorbing dye in the present invention include specific indolenine cyanine dyes described in Japanese Patent Application Nos. 2001-6326 and 2002-278057 as exemplified below.

  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 ¹ represents a hydrogen atom, a halogen atom, -NPh _2, X ² -L ¹ or a group shown below. Here, X ² represents an oxygen atom, a nitrogen atom, or a sulfur atom, and L ¹ represents a hydrocarbon group having 1 to 12 carbon atoms, an aromatic ring having a hetero atom, or 1 to 1 carbon atom containing a hetero atom. 12 hydrocarbon groups are shown. In addition, a hetero atom here shows N, S, O, a halogen atom, and Se. Xa ^- the Za described later ^- is defined as for, R ^a represents a hydrogen atom, an alkyl group, an aryl group, a substituted or unsubstituted amino group, substituted or unsubstituted amino group and a halogen atom.

R ¹ and R ² each independently represents a hydrocarbon group having 1 to 12 carbon atoms. From the storage stability of the photosensitive layer coating solution, R ¹ and R ² are preferably hydrocarbon groups having 2 or more carbon atoms, and R ¹ and R ² are bonded to each other to form a 5-membered ring or It is particularly preferable that a 6-membered ring is formed.

Ar ¹ and Ar ² 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 ¹ and Y ² may be the same or different and each represents a sulfur atom or a dialkylmethylene group having 12 or less carbon atoms. R ³ and R ⁴ 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, carboxyl groups, and sulfo groups. R ⁵ , R ⁶ , R ⁷ and R ⁸ 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. Za ⁻ represents a counter anion. However, Za ⁻ is not necessary when the cyanine dye represented by formula (a) has an anionic substituent in its structure and charge neutralization is not necessary. Preferred Za ⁻ is a halogen ion, a perchlorate ion, a tetrafluoroborate ion, a hexafluorophosphate ion, and a sulfonate ion, particularly preferably a perchlorate ion, a hexagonal salt, in view of storage stability of the photosensitive layer coating solution. Fluorophosphate ions and aryl sulfonate ions.

Specific examples of the cyanine dye represented by formula (a) that can be suitably used in the present invention include paragraph numbers [0017] to [0019] of JP-A No. 2001-133969 and JP-A No. 2002-40638. Examples thereof include those described in paragraph numbers [0012] to [0038] of the publication and paragraph numbers [0012] to [0023] of JP 2002-23360 A.

(Dye having a maximum absorption wavelength at 350 to 450 nm)
Other preferred embodiments of the sensitizing dye include dyes belonging to the following compound group and having a maximum absorption wavelength at 350 to 450 nm.
For example, polynuclear aromatics (eg, pyrene, perylene, triphenylene), xanthenes (eg, fluorescein, eosin, erythrosine, rhodamine B, rose bengal), cyanines (eg, thiacarbocyanine, oxacarbocyanine), merocyanine (Eg, merocyanine, carbomerocyanine), thiazines (eg, thionine, methylene blue, toluidine blue), acridines (eg, acridine orange, chloroflavin, acriflavine), anthraquinones (eg, anthraquinone), squalium (eg, , Squalium).

  More preferable examples of the sensitizing dye include compounds represented by the following general formulas (XIV) to (XVIII).

(In the formula (XIV), A ¹ represents a sulfur atom or NR ⁵⁰ , R ⁵⁰ represents an alkyl group or an aryl group, and L ² represents the basic nucleus of the dye in combination with the adjacent A ¹ and the adjacent carbon atom. Represents a nonmetallic atomic group to be formed, R ⁵¹ and R ⁵² each independently represent a hydrogen atom or a monovalent nonmetallic atomic group, and R ⁵¹ and R ⁵² are bonded to each other to form an acidic nucleus of the dye. W represents an oxygen atom or a sulfur atom.)
Preferable specific examples [(C-1) to (C-5)] of the compound represented by the general formula (XIV) are shown below.

(In Formula (XV), Ar ¹ and Ar ² each independently represent an aryl group, and are linked via a bond with —L ³ —, where L ³ represents —O— or —S—. W has the same meaning as that shown in formula (XIV).)
Preferable examples of the compound represented by the general formula (XV) include the following [(C-6) to (C-8)].

(In the formula (XVI), A ² represents a sulfur atom or NR ⁵⁹ , L ⁴ represents a nonmetallic atomic group that forms a basic nucleus of the dye in combination with adjacent A ² and a carbon atom, R ⁵³ , R ⁵⁴ , R ⁵⁵ , R ⁵⁶ , R ⁵⁷ and R ⁵⁸ each independently represent a monovalent nonmetallic atomic group, and R ⁵⁹ represents an alkyl group or an aryl group.)
Preferable examples of the compound represented by the general formula (XVI) include the following [(C-9) to (C-11)].

(In formula (XVII), A ³ and A ⁴ each independently represent —S— or —NR ⁶³ — or —NR ⁶⁴ —, and R ⁶³ and R ⁶⁴ each independently represents a substituted or unsubstituted alkyl group, substituted Alternatively, it represents an unsubstituted aryl group, and L ⁵ and L ⁶ each independently represents a nonmetallic atomic group that forms a basic nucleus of a dye in combination with adjacent A ³ , A ⁴ and adjacent carbon atoms. , R ⁶¹ and R ⁶² are each independently a monovalent non-metallic atomic group or can be bonded to each other to form an aliphatic or aromatic ring.
Preferable examples of the compound represented by the general formula (XVII) include the following [(C-12) to (C-15)].

  In addition, examples of suitable sensitizing dyes used in the present invention include those represented by the following formula (XVIII).

In the general formula (XVIII), A represents an aromatic ring or a hetero ring which may have a substituent, X represents an oxygen atom or a sulfur atom or —N (R ¹ ) —, and Y represents an oxygen atom or -N (R < ¹ >)-is represented. R ¹ , R ² and R ³ each independently represents a hydrogen atom or a monovalent non-metallic atomic group, and A and R ¹ , R ² and R ³ are bonded to each other to form an aliphatic group. Alternatively, an aromatic ring can be formed.

Here, when R ¹ , R ² and R ³ represent a monovalent nonmetallic atomic group, they preferably represent a substituted or unsubstituted alkyl group or aryl group.
Next, preferred examples of R ¹ , R ² and R ³ will be specifically described. Examples of preferable alkyl groups include linear, branched, and cyclic alkyl groups having 1 to 20 carbon atoms. Specific examples thereof include a methyl group, an ethyl group, a propyl group, Butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, hexadecyl, octadecyl, eicosyl, isopropyl, isobutyl, s-butyl, Examples thereof include t-butyl group, isopentyl group, neopentyl group, 1-methylbutyl group, isohexyl group, 2-ethylhexyl group, 2-methylhexyl group, cyclohexyl group, cyclopentyl group and 2-norbornyl group. Of these, linear alkyl groups having 1 to 12 carbon atoms, branched alkyl groups having 3 to 12 carbon atoms, and cyclic alkyl groups having 5 to 10 carbon atoms are more preferable.

As the substituent of the substituted alkyl group, a monovalent non-metallic atomic group other than hydrogen is used. Preferred examples include halogen atoms (—F, —Br, —Cl, —I), hydroxyl groups, alkoxy groups. Group, aryloxy group, mercapto group, alkylthio group, arylthio group, alkyldithio group, aryldithio group, amino group, N-alkylamino group, N, N-dialkylamino group, N-arylamino group, N, N-diaryl Amino group, N-alkyl-N-arylamino group, acyloxy group, carbamoyloxy group, N-alkylcarbamoyloxy group, N-arylcarbamoyloxy group, N, N-dialkylcarbamoyloxy group, N, N-diarylcarbamoyloxy Group, N-alkyl-N-arylcarbamoyloxy group, alkylsulfoxy , Arylsulfoxy group, acyloxy group, acylthio group, acylamino group, N-alkylacylamino group, N-arylacylamino group, ureido group, N′-alkylureido group, N ′, N′-dialkylureido group, N '-Arylureido group, N', N'-diarylureido group, N'-alkyl-N'-arylureido group, N-alkylureido group, N-arylureido group, N'-alkyl-N-alkylureido group N′-alkyl-N-arylureido group, N ′, N′-dialkyl-N-alkylureido group, N ′, N′-dialkyl-N-arylureido group, N′-aryl-N-alkylureido group N′-aryl-N-arylureido group, N ′, N′-diaryl-N-alkylureido group, N ′, N′-diaryl-N-aryluree Id group, N′-alkyl-N′-aryl-N-alkylureido group, N′-alkyl-N′-aryl-N-arylureido group, alkoxycarbonylamino group, aryloxycarbonylamino group, N-alkyl- N-alkoxycarbonylamino group, N-alkyl-N-aryloxycarbonylamino group, N-aryl-N-alkoxycarbonylamino group, N-aryl-N-aryloxycarbonylamino group, formyl group, acyl group, carboxyl group , Alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, N-alkylcarbamoyl group, N, N-dialkylcarbamoyl group, N-arylcarbamoyl group, N, N-diarylcarbamoyl group, N-alkyl-N-arylcarbamoyl group An alkylsulfinyl group, Arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, sulfo group (—SO ₃ H) and its conjugate base group (hereinafter referred to as sulfonate group), alkoxysulfonyl group, aryloxysulfonyl group, sulfinamoyl group, N-alkyls Rufinamoyl group, N, N-dialkylsulfinamoyl group, N-arylsulfinamoyl group, N, N-diarylsulfinamoyl group, N-alkyl-N-arylsulfinamoyl group, sulfamoyl group, N-alkyl Sulfamoyl group, N, N-dialkylsulfamoyl group, N-arylsulfamoyl group, N, N-diarylsulfamoyl group, N-alkyl-N-arylsulfamoyl group, phosphono group (—PO ₃ H ₂₎ and its conjugated base group (hereinafter referred to as phosphonato group), di Rukiruhosuhono group _{(-PO 3 (alkyl) 2)} , diaryl phosphono group _{(-PO 3 (aryl) 2)} , alkyl aryl phosphono group _{(-PO 3 (alkyl) (aryl} )), monoalkyl phosphono group (- PO ₃ H (alkyl)) and its conjugate base group (hereinafter referred to as alkylphosphonate group), monoarylphosphono group (—PO ₃ H (aryl)) and its conjugate base group (hereinafter referred to as arylphosphonate group) ), Phosphonooxy group (—OPO ₃ H ₂ ) and its conjugate base group (hereinafter referred to as phosphonatoxy group), dialkylphosphonooxy group (—OPO ₃ (alkyl) ₂ ), diarylphosphonooxy group (—OPO _3). (aryl) _2), alkylaryl phosphono group _{(-OPO 3 (alkyl) (aryl} )), monoalkyl phosphonates Oxy group (-OPO ₃ H (alkyl)) and its conjugated base group (hereinafter referred to as alkylphosphonato group), monoarylphosphono group (-OPO ₃ H (aryl)) and its conjugated base group (hereinafter And cyano group, nitro group, aryl group, heteroaryl group, alkenyl group, alkynyl group and silyl group.
Specific examples of the alkyl group in these substituents include the aforementioned alkyl groups, which may further have a substituent.

  Specific examples of the aryl group include phenyl group, biphenyl group, naphthyl group, tolyl group, xylyl group, mesityl group, cumenyl group, chlorophenyl group, bromophenyl group, chloromethylphenyl group, hydroxyphenyl group, methoxyphenyl group. , Ethoxyphenyl group, phenoxyphenyl group, acetoxyphenyl group, benzoyloxyphenyl group, methylthiophenyl group, phenylthiophenyl group, methylaminophenyl group, dimethylaminophenyl group, acetylaminophenyl group, carboxyphenyl group, methoxycarbonylphenyl Group, ethoxyphenylcarbonyl group, phenoxycarbonylphenyl group, N-phenylcarbamoylphenyl group, phenyl group, cyanophenyl group, sulfophenyl group, sulfonatophenyl group, phosphonopheny Group, and a phosphate Hona preparative phenyl group.

As the heteroaryl group, a group derived from a monocyclic or polycyclic aromatic ring containing at least one of nitrogen, oxygen and sulfur atoms is used, and examples of the heteroaryl ring in the particularly preferred heteroaryl group include Is, for example, thiophene, thiathrene, furan, pyran, isobenzofuran, chromene, xanthene, phenoxazine, pyrrole, pyrazole, isothiazole, isoxazole, pyrazine, pyrimidine, pyridazine, indolizine, isoindolizine, indolizine, indazole, indazole, Purine, quinolidine, isoquinoline, phthalazine, naphthyridine, quinazoline, sinoline, pteridine, carbazole, carboline, phenanthrine, acridine, perimidine, phenanthrolin, phthalazine, phenalazine, phenoxazine, fura Emissions, phenoxazine and the like, they further may be benzo-fused or may have a substituent.

Examples of alkenyl groups include vinyl, 1-propenyl, 1-butenyl, cinnamyl, 2-chloro-1-ethenyl, etc. Examples of alkynyl include ethynyl, 1 -Propynyl group, 1-butynyl group, trimethylsilylethynyl group and the like. Examples of G ¹ in the acyl group (G ¹ CO—) include hydrogen and the above alkyl groups and aryl groups. Among these substituents, even more preferred are halogen atoms (—F, —Br, —Cl, —I), alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, N-alkylamino groups, N, N -Dialkylamino group, acyloxy group, N-alkylcarbamoyloxy group, N-arylcarbamoyloxy group, acylamino group, formyl group, acyl group, carboxyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, N-alkylcarbamoyl group Group, N, N-dialkylcarbamoyl group, N-arylcarbamoyl group, N-alkyl-N-arylcarbamoyl group, sulfo group, sulfonate group, sulfamoyl group, N-alkylsulfamoyl group, N, N-dialkylsulfa group Moyl group, N-arylsulfur Amoyl group, N-alkyl-N-arylsulfamoyl group, phosphono group, phosphonate group, dialkyl phosphono group, diaryl phosphono group, monoalkyl phosphono group, alkyl phosphonate group, monoaryl phosphono group, aryl phosphine group And an onato group, a phosphonooxy group, a phosphonatoxy group, an aryl group, an alkenyl group, and an alkylidene group (such as a methylene group).

  On the other hand, examples of the alkylene group in the substituted alkyl group include divalent organic residues obtained by removing any one of the hydrogen atoms on the alkyl group having 1 to 20 carbon atoms. Can include linear alkylene groups having 1 to 12 carbon atoms, branched chains having 3 to 12 carbon atoms, and cyclic alkylene groups having 5 to 10 carbon atoms.

Specific examples of preferred substituted alkyl groups as R ¹ , R ² , or R ³ obtained by combining the above substituents and alkylene groups include chloromethyl group, bromomethyl group, 2-chloroethyl group, trifluoromethyl group, methoxy Methyl group, methoxyethoxyethyl group, allyloxymethyl group, phenoxymethyl group, methylthiomethyl group, tolylthiomethyl group, ethylaminoethyl group, diethylaminopropyl group, morpholinopropyl group, acetyloxymethyl group, benzoyloxymethyl group, N -Cyclohexylcarbamoyloxyethyl group, N-phenylcarbamoyloxyethyl group, acetylaminoethyl group, N-methylbenzoylaminopropyl group, 2-oxoethyl group, 2-oxopropyl group, carboxypropyl group, methoxycarbonyl Bonylethyl group, allyloxycarbonylbutyl group, chlorophenoxycarbonylmethyl group, carbamoylmethyl group, N-methylcarbamoylethyl group, N, N-dipropylcarbamoylmethyl group, N- (methoxyphenyl) carbamoylethyl group, N-methyl- N- (sulfophenyl) carbamoylmethyl group, sulfobutyl group, sulfonatopropyl group, sulfonatobutyl group, sulfamoylbutyl group, N-ethylsulfamoylmethyl group, N, N-dipropylsulfamoylpropyl group, N-tolyl Sulfamoylpropyl group, N-methyl-N- (phosphonophenyl) sulfamoyloctyl group, phosphonobutyl group, phosphonatohexyl group, diethylphosphonobutyl group, diphenylphosphonopropyl group, methylphosphonobutyl group, methylphospho Suphonatobutyl group, Tolylphosphonohexyl group, Tolylphosphonatohexyl group, Phosphonoxyoxy group, Phosphonatooxybutyl group, Benzyl group, Phenethyl group, α-methylbenzyl group, 1-methyl-1-phenylethyl group, p -Methylbenzyl group, cinnamyl group, allyl group, 1-propenylmethyl group, 2-butenyl group, 2-methylallyl group, 2-methylpropenylmethyl group, 2-propynyl group, 2-butynyl group, 3-butynyl group, etc. Can be mentioned.

Specific examples of preferred aryl groups as R ¹ , R ² , or R ³ include those in which 1 to 3 benzene rings form a condensed ring, and those in which a benzene ring and a 5-membered unsaturated ring form a condensed ring Specific examples include a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, an indenyl group, an acenaphthenyl group, and a fluorenyl group. Among these, a phenyl group and a naphthyl group are more preferable. preferable.

Specific examples of the preferred substituted aryl group as R ¹ , R ² , or R ³ include a monovalent nonmetallic atomic group (other than a hydrogen atom) as a substituent on the ring-forming carbon atom of the aryl group. What has is used. Examples of preferred substituents include the alkyl groups, substituted alkyl groups, and those previously shown as substituents in the substituted alkyl group. Preferred examples of such a substituted aryl group include biphenyl group, tolyl group, xylyl group, mesityl group, cumenyl group, chlorophenyl group, bromophenyl group, fluorophenyl group, chloromethylphenyl group, trifluoromethylphenyl group. Hydroxyphenyl group, methoxyphenyl group, methoxyethoxyphenyl group, allyloxyphenyl group, phenoxyphenyl group, methylthiophenyl group, tolylthiophenyl group, ethylaminophenyl group, diethylaminophenyl group, morpholinophenyl group, acetyloxyphenyl group, Benzoyloxyphenyl group, N-cyclohexylcarbamoyloxyphenyl group, N-phenylcarbamoyloxyphenyl group, acetylaminophenyl group, N-methylbenzoylaminophenyl group, cal Xiphenyl group, methoxycarbonylphenyl group, allyloxycarbonylphenyl group, chlorophenoxycarbonylphenyl group, carbamoylphenyl group, N-methylcarbamoylphenyl group, N, N-dipropylcarbamoylphenyl group, N- (methoxyphenyl) carbamoylphenyl group N-methyl-N- (sulfophenyl) carbamoylphenyl group, sulfophenyl group, sulfonatophenyl group, sulfamoylphenyl group, N-ethylsulfamoylphenyl group, N, N-dipropylsulfamoylphenyl group, N-tolylsulfamoylphenyl group, N-methyl-N- (phosphonophenyl) sulfamoylphenyl group, phosphonophenyl group, phosphonatophenyl group, diethylphosphonophenyl group, diphenylphosphonophenyl Methylphosphonophenyl group, methylphosphonatophenyl group, tolylphosphonophenyl group, tolylphosphonophenyl group, allylphenyl group, 1-propenylmethylphenyl group, 2-butenylphenyl group, 2-methylallylphenyl group, Examples include 2-methylpropenylphenyl group, 2-propynylphenyl group, 2-butynylphenyl group, 3-butynylphenyl group, and the like.

In addition, more preferable examples of R ² and R ³ include a substituted or unsubstituted alkyl group. A more preferable example of R ¹ includes a substituted or unsubstituted aryl group. The reason for this is not clear, but by having such a substituent, the interaction between the electronically excited state caused by light absorption and the initiator compound becomes particularly large, generating radicals, acids or bases of the initiator compound. It is estimated that the efficiency is improved.

Next, A in the general formula (XVIII) will be described. A represents an aromatic ring or a hetero ring which may have a substituent. Specific examples of the aromatic ring or hetero ring which may have a substituent include R ¹ and R ² in the general formula (XVIII). Or the same as those exemplified in the above description of R ³ .
Among them, preferable A includes an alkoxy group, a thioalkyl group, and an aryl group having an amino group, and particularly preferable A includes an aryl group having an amino group.

  Next, Y in the formula (XVIII) will be described. Y represents a nonmetallic atomic group necessary for forming a heterocyclic ring in cooperation with the above-mentioned A and adjacent carbon atoms. Examples of such a heterocyclic ring include 5-, 6-, and 7-membered nitrogen-containing or sulfur-containing heterocyclic rings that may have a condensed ring, and preferably 5- or 6-membered heterocyclic rings.

Examples of nitrogen-containing heterocycles include, for example, LGBrooker et al., Journal of American Chemical Society, Vol. 73 (1951), p. Any of those known to constitute a basic nucleus in merocyanine dyes described in 5326-5358 and references can be suitably used.
Specific examples include thiazoles (for example, thiazole, 4-methylthiazole, 4-phenylthiazole, 5-methylthiazole, 5-phenylthiazole, 4,5-dimethylthiazole, 4,5-diphenylthiazole, 4,5- Di (p-methoxyphenylthiazole), 4- (2-thienyl) thiazole, 4,5-di (2-furyl) thiazole, etc.), benzothiazoles (for example, benzothiazole, 4-chlorobenzothiazole, 5-chloro Benzothiazole, 6-chlorobenzothiazole, 7-chlorobenzothiazole, 4-methylbenzothiazole, 5-methylbenzothiazole, 6-methylbenzothiazole, 5-bromobenzothiazole, 4-phenylbenzothiazole, 5-phenylbenzothiazole 4-methoxybenzo Azole, 5-methoxybenzothiazole, 6-methoxybenzothiazole, 5-iodobenzothiazole, 6-iodobenzothiazole, 4-ethoxybenzothiazole, 5-ethoxybenzothiazole, tetrahydrobenzothiazole, 5,6-dimethoxybenzothiazole, 5,6-dioxymethylenebenzothiazole, 5-hydroxybenzothiazole, 6-hydroxybenzothiazole, 6-dimethylaminobenzothiazole, 5-ethoxycarbonylbenzothiazole, etc.), naphthothiazoles (for example, naphtho [1,2 ] Thiazole, naphtho [2,1] thiazole, 5-methoxynaphtho [2,1] thiazole, 5-ethoxynaphtho [2,1] thiazole, 8-methoxynaphtho [1,2] thiazole, 7-methoxynaphtho [ , 2] thiazole, etc.), thianaphtheno-7 ′, 6 ′, 4,5-thiazole (for example, 4′-methoxythianaphtheno-7 ′, 6 ′, 4,5-thiazole, etc.), oxazole ( For example, 4-methyl oxazole, 5-methyl oxazole, 4-phenyl oxazole, 4,5-diphenyl oxazole, 4-ethyl oxazole, 4,5-dimethyl oxazole, 5-phenyl oxazole, etc.), benzoxazoles (benzoxazole, 5-chlorobenzoxazole, 5-methylbenzoxazole, 5-phenylbenzoxazole, 6-methylbenzoxazole, 5,6-dimethylbenzoxazole, 4,6-dimethylbenzoxazole, 6-methoxybenzoxazole, 5-methoxybenzo Oxazole, 4-ethoxybe Nzooxazole, 5-chlorobenzoxazole, 6-methoxybenzoxazole, 5-hydroxybenzoxazole, 6-hydroxybenzoxazole, etc.),

Naphthoxazoles (eg, naphtho [1,2] oxazole, naphtho [2,1] oxazole, etc.), selenazoles (eg, 4-methylselenazole, 4-phenylselenazole, etc.), benzoselenazoles ( For example, benzoselenazole, 5-chlorobenzoselenazole, 5-methoxybenzoselenazole, 5-hydroxybenzoselenazole, tetrahydrobenzoselenazole, etc.), naphthoselenazoles (for example, naphtho [1,2] selenazole, Naphtho [2,1] selenazole, etc.], thiazolines (for example, thiazoline, 4-methylthiazoline, 4,5-dimethylthiazoline, 4-phenylthiazoline, 4,5-di (2-furyl) thiazoline, 4,5 -Diphenylthiazoline, 4,5-di (p-methoxyphenyl) thi Zoline, etc.), 2-quinolines (for example, quinoline, 3-methylquinoline, 5-methylquinoline, 7-methylquinoline, 8-methylquinoline, 6-chloroquinoline, 8-chloroquinoline, 6-methoxyquinoline, 6- Ethoxyquinoline, 6-hydroxyquinoline, 8-hydroxyquinoline, etc.), 4-quinolines (eg, quinoline, 6-methoxyquinoline, 7-methylquinoline, 8-methylquinoline, etc.), 1-isoquinolines (eg, Isoquinoline, 3,4-dihydroisoquinoline, etc.), 3-isoquinolines (eg, isoquinoline, etc.), benzimidazoles (eg, 1,3-dimethylbenzimidazole, 1,3-diethylbenzimidazole, 1-ethyl-3) -Phenylbenzimidazole, etc.), 3,3-dialkylin Renins (eg, 3,3-dimethylindolenine, 3,3,5-trimethylindolenine, 3,3,7-trimethylindolenine, etc.), 2-pyridines (eg, pyridine, 5-methylpyridine, Etc.), 4-pyridine (for example, pyridine etc.) and the like. Moreover, the substituents of these rings may combine to form a ring.

Examples of the sulfur-containing heterocycle include a dithiol partial structure in dyes described in JP-A-3-296759.
Specific examples include benzodithiols (eg, benzodithiol, 5-t-butylbenzodithiol, 5-methylbenzodithiol, etc.), naphthodithiols (eg, naphtho [1,2] dithiol, naphtho [2,1 Dithiols, etc.), dithiols (for example, 4,5-dimethyldithiols, 4-phenyldithiols, 4-methoxycarbonyldithiols, 4,5-dimethoxycarbonyldithiols, 4,5-diethoxycarbonyldithiols) 4,5-ditrifluoromethyldithiol, 4,5-dicyanodithiol, 4-methoxycarbonylmethyldithiol, 4-carboxymethyldithiol, etc.).

  Of the examples of the nitrogen-containing or sulfur-containing heterocycle formed by Y in cooperation with the above-mentioned A and the adjacent carbon atom in the general formula (XVIII) described above, the partial structure of the following general formula (XVIII-2) The dye having the structure represented by the formula is particularly preferable because it provides a photosensitive composition having high sensitizing ability and extremely excellent storage stability. The dye having the structure represented by the general formula (XVIII-2) is a compound described in detail in Japanese Patent Application Laid-Open No. 2004-318049 by the present applicant as a novel compound.

(In the general formula (XVIII-2), A represents an aromatic ring or a hetero ring which may have a substituent, and X represents an oxygen atom, a sulfur atom or -N (R ¹ )-. R ¹ , R ⁴ , R ⁵ , R ⁶ each independently represents a hydrogen atom or a monovalent non-metallic atomic group, and A and R ¹ , R ⁴ , R ⁵ , R ⁶ are bonded to each other to form a fat An aromatic or aromatic ring can be formed.)
In formula (XVIII-2), A and R ¹ are the same as in the general formula (XVIII), R ⁴ and R ² in the general formula (XVIII), R ⁵ is R ³ in the general formula (XVIII) And R ⁶ has the same meaning as R ¹ in formula (XVIII).

  Next, the compound represented by formula (XVIII-3), which is a preferred embodiment of the compound represented by formula (XVIII) used in the present invention, will be described.

In the general formula (XVIII-3), A represents an aromatic ring or a hetero ring which may have a substituent, and X represents an oxygen atom, a sulfur atom, or —N (R ¹ ) —. R ¹ , R ⁴ and R ⁵ are each independently a hydrogen atom or a monovalent nonmetallic atomic group, and A and R ¹ , R ⁴ and R ⁵ are each aliphatic or aromatic. Can be linked to form a ring. Ar represents an aromatic ring or a heterocyclic ring having a substituent. However, the substituent on the Ar skeleton needs to have a sum of Hammett values greater than zero. Here, the sum of the Hammett values is greater than 0 means that the substituent has one substituent, and the Hammett value of the substituent may be greater than 0, and has a plurality of substituents. The sum of Hammett values at may be greater than zero.

In formula (XVIII-3), A and R ¹ have the same meanings as in formula (XVIII), R ⁴ and R ² in the general formula (XVIII), R ⁵ is R ³ in the general formula (XVIII) It is synonymous with. Ar represents an aromatic ring or heterocyclic ring having a substituent, and specific examples thereof include an aromatic ring or heterocyclic ring having a substituent among those previously described in the description of A in the general formula (XVIII). The specific example which concerns on is mentioned similarly. However, as a substituent that can be introduced into Ar in the general formula (XVIII-3), it is essential that the sum of Hammett values is 0 or more. Examples of such a substituent include a trifluoromethyl group, Examples thereof include a carbonyl group, an ester group, a halogen atom, a nitro group, a cyano group, a sulfoxide group, an amide group, and a carboxyl group. The Hammett values of these substituents are shown below. Trifluoromethyl group (—CF ₃ , m: 0.43, p: 0.54), carbonyl group (eg, —COHm: 0.36, p: 0.43), ester group (—COOCH ₃ , m: 0 .37, p: 0.45), halogen atom (for example, Cl, m: 0.37, p: 0.23), cyano group (—CN, m: 0.56, p: 0.66), sulfoxide group (For example, —SOCH ₃ , m: 0.52, p: 0.45), an amide group (for example, —NHCOCH ₃ , m: 0.21, p: 0.00), a carboxyl group (—COOH, m: 0. 37, p: 0.45). The parenthesis represents the introduction position of the substituent in the aryl skeleton and the Hammett value, and (m: 0.50) is the Hammett value of 0.50 when the substituent is introduced at the meta position. Indicates that there is. Among these, preferable examples of Ar include a phenyl group having a substituent, and preferable substituents on the Ar skeleton include an ester group and a cyano group. The substitution position is particularly preferably located at the ortho position on the Ar skeleton.

  Although the preferable specific example (Exemplary compound D1-Exemplified compound D56) of the winding-up dye represented by general formula (XVIII) which concerns on this invention below is shown, this invention is not limited to these.

  Among the sensitizing dyes applicable to the present invention, the compound represented by the general formula (XVIII) is preferable from the viewpoint of sensitivity.

  The above sensitizing dye can be subjected to various chemical modifications as follows for the purpose of improving the characteristics of the photosensitive composition of the present invention. For example, by combining a sensitizing dye and an addition polymerizable compound structure (for example, an acryloyl group or a methacryloyl group) by a method such as a covalent bond, an ionic bond, or a hydrogen bond, An improvement in the effect of suppressing the unnecessary precipitation of the dye from the crosslinked cured film can be obtained.

  In the present invention, as pigments used as sensitizing dyes, commercially available pigments and Color Index (CI) Handbook, “Latest Pigment Handbook” (edited by Japan Pigment Technical Association, published in 1977), “Latest Pigment Application Technology” (CMC Publishing, published in 1986) and “Printing Ink Technology” published by CMC Publishing, published in 1984) can be used.

  Examples of the pigment include black pigments, yellow pigments, orange pigments, brown pigments, red pigments, purple pigments, blue pigments, green pigments, fluorescent pigments, metal powder pigments, and other polymer-bonded dyes. Specifically, insoluble azo pigments, azo lake pigments, condensed azo pigments, chelate azo pigments, phthalocyanine pigments, anthraquinone pigments, perylene and perinone pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, isoindolinone pigments , Quinophthalone pigments, dyed lake pigments, azine pigments, nitroso pigments, nitro pigments, natural pigments, fluorescent pigments, inorganic pigments, carbon black, and the like. Among these pigments, carbon black is preferable.

  These pigments may be used without surface treatment, or may be used after surface treatment. The surface treatment method includes a method of surface coating with a resin or wax, a method of attaching a surfactant, a method of bonding a reactive substance (eg, silane coupling agent, epoxy compound, polyisocyanate, etc.) to the pigment surface, etc. Can be considered. The above-mentioned surface treatment methods are described in “Characteristics and Applications of Metal Soap” (Yokoshobo), “Printing Ink Technology” (CMC Publishing, 1984) and “Latest Pigment Application Technology” (CMC Publishing, 1986). Yes.

  The particle diameter of the pigment is preferably in the range of 0.01 μm to 10 μm, more preferably in the range of 0.05 μm to 1 μm, particularly from the viewpoint of dispersibility in the coating solution and uniformity of the photosensitive layer. It is preferably in the range of 0.1 μm to 1 μm.

  As a method for dispersing the pigment, a known dispersion technique used in ink production, toner production, or the like can be used. Examples of the disperser include an ultrasonic disperser, a sand mill, an attritor, a pearl mill, a super mill, a ball mill, an impeller, a disperser, a KD mill, a colloid mill, a dynatron, a three-roll mill, and a pressure kneader. Details are described in "Latest Pigment Applied Technology" (CMC Publishing, 1986).

Further, when the photosensitive composition of the present invention is applied to a photosensitive lithographic printing plate, these (C) sensitizing dyes may be added to the same layer as the other components of the photosensitive layer, or another layer may be added. The same effect can be obtained even if it is added thereto, but when a negative photosensitive lithographic printing plate is produced, the optical density at the absorption maximum in the wavelength range of 300 nm to 1200 nm of the photosensitive layer is 0. It is preferably between 1 and 3.0. When this range is deviated, the sensitivity tends to be low. Since the optical density is determined by the addition amount of the sensitizing dye and the thickness of the photosensitive layer, the predetermined optical density can be obtained by controlling both conditions.
The optical density of the photosensitive layer can be measured by a conventional method. As a measuring method, for example, on a transparent or white support, a photosensitive layer having a thickness appropriately determined in a range where the coating amount after drying is necessary as a lithographic printing plate is formed, and a transmission type optical densitometer is used. Examples thereof include a method of measuring, a method of forming a photosensitive layer on a reflective support such as aluminum, and measuring a reflection density.

  The content of the sensitizing dye (C) contained in the photosensitive composition of the present invention is photosensitive from the viewpoint of the uniformity of the sensitizing dye dispersed in the composition and the durability of the formed film. It is preferably in the range of 0.01 to 50% by mass, more preferably in the range of 0.1 to 30% by mass, and 0.5 to 10% by mass with respect to the total solid content of the composition. Most preferred.

  These hexaarylbiimidazole compounds are 0.1 to 50% by weight, preferably 0.5 to 30% by weight, particularly preferably 1 to 20% by weight, based on the total solid content of the photosensitive composition. It can be added to the coating solution. When the addition amount is within this range, sufficient sensitivity can be obtained, and when the photosensitive composition of the present invention is applied as a photosensitive layer of a photosensitive lithographic printing plate, storage stability is improved. These hexaarylbiimidazole compounds may be used alone or in combination of two or more. Moreover, these hexaarylbiimidazole compounds may be added to the same layer as other components, or another layer may be provided and added thereto.

(D) Polymerizable compound having an ethylenically unsaturated double bond (D) The polymerizable compound having an ethylenically unsaturated double bond in the present invention is an addition polymerizable compound having at least one ethylenically unsaturated double bond. The compound is selected from compounds having at least one ethylenically unsaturated bond, preferably two or more. Such a compound group is widely known in the industrial field, and can be used without any particular limitation in the present invention. These have chemical forms such as monomers, prepolymers, that is, dimers, trimers and oligomers, or mixtures thereof, and copolymers thereof. Examples of monomers and copolymers thereof include unsaturated carboxylic acids (for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc.), and esters and amides thereof. In this case, an ester of an unsaturated carboxylic acid and an aliphatic polyhydric alcohol compound, or an amide of an unsaturated carboxylic acid and an aliphatic polyvalent amine compound is used. In addition, an addition reaction product of an unsaturated carboxylic acid ester or amide having a nucleophilic substituent such as a hydroxyl group, amino group or mercapto group with a monofunctional or polyfunctional isocyanate or epoxy, and monofunctional or polyfunctional A dehydration condensation reaction product with a functional carboxylic acid is also preferably used. Further, an addition reaction product of an unsaturated carboxylic acid ester or amide having an electrophilic substituent such as an epoxy group or an epoxy group with a monofunctional or polyfunctional alcohol, amine or thiol, a halogen group or In addition, 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, it is also possible to use a group of compounds substituted with unsaturated phosphonic acid, styrene, vinyl ether or the like instead of the unsaturated carboxylic acid.

  Specific examples of the monomer of an ester of an aliphatic polyhydric alcohol compound and an unsaturated carboxylic acid include acrylic acid esters such as ethylene glycol diacrylate, triethylene glycol diacrylate, 1,3-butanediol diacrylate, and tetramethylene glycol. Diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, trimethylolpropane tri (acryloyloxypropyl) ether, trimethylolethane triacrylate, hexanediol diacrylate, 1,4-cyclohexanediol diacrylate , Tetraethylene glycol diacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate , Pentaerythritol tetraacrylate, dipentaerythritol diacrylate, dipentaerythritol hexaacrylate, sorbitol triacrylate, sorbitol tetraacrylate, sorbitol pentaacrylate, sorbitol hexaacrylate, tri (acryloyloxyethyl) isocyanurate, polyester acrylate oligomer.

  Methacrylic acid esters include tetramethylene glycol dimethacrylate, triethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, ethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, Hexanediol dimethacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol dimethacrylate, dipentaerythritol hexamethacrylate, sorbitol trimethacrylate, sorbitol tetramethacrylate, bis [p- (3-methacryloxy- 2-hydroxypro ) Phenyl] dimethyl methane, bis - [p- (methacryloxyethoxy) phenyl] dimethyl methane.

  Itaconic acid esters include ethylene glycol diitaconate, propylene glycol diitaconate, 1,3-butanediol diitaconate, 1,4-butanediol diitaconate, tetramethylene glycol diitaconate, pentaerythritol diitaconate And sorbitol tetritaconate. Examples of crotonic acid esters include ethylene glycol dicrotonate, tetramethylene glycol dicrotonate, pentaerythritol dicrotonate, and sorbitol tetradicrotonate. Examples of isocrotonic acid esters include ethylene glycol diisocrotonate, pentaerythritol diisocrotonate, and sorbitol tetraisocrotonate. Examples of maleic acid esters include ethylene glycol dimaleate, triethylene glycol dimaleate, pentaerythritol dimaleate, and sorbitol tetramaleate.

  Examples of other esters include aliphatic alcohol esters described in JP-B-46-27926, JP-B-51-47334, JP-A-57-196231, JP-A-59-5240, JP Those having an aromatic skeleton described in JP-A-59-5241 and JP-A-2-226149, those containing an amino group described in JP-A-1-165613, and the like are also preferably used. Furthermore, the ester monomers described above can also be used as a mixture.

Specific examples of amide monomers of aliphatic polyvalent amine compounds and unsaturated carboxylic acids include methylene bis-acrylamide, methylene bis-methacrylamide, 1,6-hexamethylene bis-acrylamide, 1,6-hexamethylene bis. -Methacrylamide, diethylenetriamine trisacrylamide, xylylene bisacrylamide, xylylene bismethacrylamide and the like. Examples of other preferable amide monomers include those having a cyclohexylene structure described in JP-B No. 54-21726.

  Further, urethane-based addition polymerizable compounds produced by using an addition reaction of isocyanate and hydroxyl group are also suitable. Specific examples thereof include, for example, one 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 hydroxyl group represented by the following formula (1) to a polyisocyanate compound having two or more isocyanate groups. Etc.

^{_{CH 2 = C (R 4)}} COOCH 2 CH (R 5) OH (1)
(However, R ⁴ and R ⁵ represent H or CH _3. )

  Also, urethane acrylates such as those described in JP-A-51-37193, JP-B-2-32293, and JP-B-2-16765, JP-B-58-49860, JP-B-56-17654, Urethane compounds having an ethylene oxide skeleton described in JP-B-62-39417 and JP-B-62-39418 are also suitable. Further, by using addition polymerizable compounds having an amino structure or a sulfide structure in the molecule described in JP-A-63-277653, JP-A-63-260909, and JP-A-1-105238, It is possible to obtain an image recording material having an excellent photosensitive speed.

  Other examples include polyester acrylates, epoxy resins and (meth) acrylic acid as described in JP-A-48-64183, JP-B-49-43191, JP-B-52-30490, and JP-A-52-30490. Mention may be made of polyfunctional acrylates and methacrylates such as reacted epoxy acrylates. Further, specific unsaturated compounds described in JP-B-46-43946, JP-B-1-40337 and JP-B-1-40336, vinylphosphonic acid compounds described in JP-A-2-25493, and the like can also be mentioned. . In some cases, a structure containing a perfluoroalkyl group described in JP-A-61-22048 is preferably used. Furthermore, Journal of Japan Adhesion Association vol. 20, no. 7, pages 300 to 308 (1984), which are introduced as photocurable monomers and oligomers, can also be used.

  About such (D) polymeric compound, the detail of usage methods, such as the structure, single use, combined use, and addition amount, can be arbitrarily set according to the performance design of the final photosensitive composition. For example, it is selected from the following viewpoints. From the viewpoint of photosensitive speed, a structure having a high unsaturated group content per molecule is preferable, and in many cases, a bifunctional or higher functionality is preferable. Further, in order to increase the strength of the image area, that is, the cured film, those having three or more functionalities are preferable, and further, different functional numbers and different polymerizable groups (for example, acrylic acid ester, methacrylic acid ester, styrenic compound, vinyl ether). It is also effective to adjust both photosensitivity and strength by using a compound of the type). A compound having a large molecular weight or a compound having high hydrophobicity is excellent in photosensitive speed and film strength, but is not preferable in terms of development speed and precipitation in a developer. In addition, compatibility with other components in the photosensitive layer of the photosensitive composition (for example, (A) component, (B) component, (C) sensitizing dye, polymerization inhibitor, colorant, etc.) and dispersibility On the other hand, the selection and use method of the polymerizable compound as the component (D) is an important factor. For example, the compatibility may be improved by using a low-purity compound or using two or more kinds in combination.

Further, when the photosensitive composition of the present invention is applied to a photosensitive layer of a photosensitive lithographic printing plate, a specific structure is used for the purpose of improving the adhesion of the support of the photosensitive lithographic printing plate and the overcoat layer described later. May also be selected. Regarding the compounding ratio of the polymerizable compound in the photosensitive layer, a larger amount is more advantageous in terms of sensitivity. However, when the amount is too large, an undesirable phase separation occurs or a problem in the production process due to the adhesiveness of the photosensitive layer ( For example, problems such as transfer of photosensitive layer components and manufacturing defects due to adhesion) and precipitation from a developer may occur. From these viewpoints, the polymerizable compound (D) is preferably used in the range of 5 to 80% by mass, and more preferably 25 to 75% by mass with respect to the nonvolatile component in the photosensitive layer. These may be used alone or in combination of two or more.
In addition, when the photosensitive composition of the present invention is applied to a photosensitive lithographic printing plate as described above, the method of using the polymerizable compound (D) is the degree of polymerization inhibition with respect to oxygen, resolution, fogging, and refractive index change. From the viewpoint of surface tackiness, etc., an appropriate structure, blending, and addition amount can be arbitrarily selected. Further, in some cases, a layer configuration / coating method such as undercoating or overcoating can be carried out.

(E) Other components In addition to the above-described components, other components suitable for the application, production method, and the like can be appropriately added to the photosensitive composition of the present invention. Hereinafter, preferred additives will be exemplified.
(E-1) Binder polymer When the photosensitive lithographic printing plate which is a preferred embodiment of the photosensitive composition of the present invention is applied to the photosensitive layer, the photosensitive composition further includes a binder from the viewpoint of improving film properties. It is preferred to use a polymer.
As the binder polymer, it is preferable to contain a linear organic polymer. As such a “linear organic polymer”, any compound may be used, but preferably water or weak alkaline water soluble or swellable to enable water development or weak alkaline water development. A linear organic polymer is selected. The linear organic high molecular polymer is selected and used not only as a film-forming agent for the composition but also according to its use as water, weak alkaline water or an organic solvent developer. For example, when a water-soluble organic polymer is used, water development is possible. Examples of such linear organic high molecular polymers include addition polymers having a carboxylic acid group in the side chain, such as JP 59-44615, JP-B 54-34327, JP-B 58-12777, and JP-B. 54-25957, JP-A-54-92723, JP-A-59-53836, JP-A-59-71048, ie, methacrylic acid copolymer, acrylic acid copolymer , Itaconic acid copolymer, crotonic acid copolymer, maleic acid copolymer, and partially esterified maleic acid copolymer. Similarly, there is an acidic cellulose derivative having a carboxylic acid group in the side chain. In addition, those obtained by adding a cyclic acid anhydride to an addition polymer having a hydroxyl group are useful.

Among these, [benzyl (meth) acrylate / (meth) acrylic acid / other addition polymerizable vinyl monomers as required] copolymer and [allyl (meth) acrylate / (meth) acrylic acid / as required Other addition-polymerizable vinyl monomers] are preferred because they are excellent in the balance of film strength, sensitivity and developability.
In addition, Japanese Patent Publication No. 7-2004, Japanese Patent Publication No. 7-120041, Japanese Patent Publication No. 7-120042, Japanese Patent Publication No. 8-12424, Japanese Patent Laid-Open No. 63-287944, Japanese Patent Laid-Open No. 63-287947, Japanese Patent Laid-Open No. The urethane-based binder polymer containing an acid group described in each publication of Japanese Patent No. 271741 and Japanese Patent Application No. 10-116232 is very excellent in strength, and is advantageous in terms of printing durability and suitability for low exposure. It is.
A binder having an amide group described in JP-A No. 11-171907 is suitable because it has excellent developability and film strength.

In addition, polyvinyl pyrrolidone, polyethylene oxide, and the like are useful as the water-soluble linear organic polymer. In order to increase the strength of the cured film, alcohol-soluble nylon, polyether of 2,2-bis- (4-hydroxyphenyl) -propane and epichlorohydrin, and the like are also useful. These linear organic high molecular polymers can be mixed in an arbitrary amount in the entire composition. However, when it exceeds 90% by mass, a favorable result is not given in terms of the strength of the formed image. Preferably it is 30-85 mass%. The photopolymerizable compound having an ethylenically unsaturated double bond and the linear organic polymer are preferably in the range of 1/9 to 7/3 by mass ratio. In a preferred embodiment, a binder polymer that is substantially insoluble in water and soluble in alkali is used. By doing so, an organic solvent that is not environmentally preferable is not used as the developer, or the amount can be limited to a very small amount. In such a method of use, the acid value of the binder polymer (the acid content per gram of the polymer expressed as a chemical equivalent number) and the molecular weight are appropriately selected from the viewpoint of image strength and developability. The preferred acid value is 0.4 to 3.0 meq / g, and the preferred molecular weight is in the range of 3000 to 500,000 in terms of weight average molecular weight, more preferably the acid value is 0.6 to 2.0 and the molecular weight is It is in the range of 10,000 to 300,000.

(E-2) Co-initiator The photosensitive composition of this invention may contain a co-initiator from the point of a sensitivity improvement.

  Preferred coinitiators in the present invention include (a) aromatic ketones, (b) onium salt compounds, (c) organic peroxides, (d) thio compounds, (e) ketoxime ester compounds, (f) Examples thereof include borate compounds, (g) azinium compounds, (h) metallocene compounds, (i) active ester compounds, (j) compounds having a carbon halogen bond, and (k) azo compounds. Specific examples of the above (a) to (k) are given below, but the present invention is not limited to these.

(A) Aromatic ketones (a) Aromatic ketones preferred as the radical initiator used in the present invention include “RADIATION CURING IN POLYMER SCIENCE AND TECHNOLOGY” P. Fouassier, J. et al. F. Examples include compounds having a benzophenone skeleton or a thioxanthone skeleton described in Rabek (1993), p77-117. For example,

Is mentioned. Among them, particularly preferable examples of (a) aromatic ketones include α-thiobenzophenone compounds described in JP-B-47-6416 and benzoin ether compounds described in JP-B-47-3981, for example, the following compounds.

  Examples of the α-substituted benzoin compounds described in JP-B-47-22326 include the following compounds.

  Examples thereof include benzoin derivatives described in JP-B-47-23664, aroylphosphonic acid esters described in JP-A-57-30704, dialkoxybenzophenones described in JP-B-60-26483, for example, the following compounds.

  Examples of the benzoin ethers described in JP-B-60-26403 and JP-A-62-181345 include the following compounds.

  Α-aminobenzophenones described in JP-B-1-34242, US Pat. No. 4,318,791, and European Patent 0284561A1, for example, the following compounds may be mentioned.

  P-Di (dimethylaminobenzoyl) benzene described in JP-A-2-211452, for example, the following compounds may be mentioned.

  Examples of the thio-substituted aromatic ketone described in JP-A-61-194062 include the following compounds.

  Examples of the acylphosphine sulfide described in JP-B-2-9597 include the following compounds.

  Examples of the acylphosphine described in JP-B-2-9596 include the following compounds.

  Further, thioxanthones described in JP-B-63-61950, coumarins described in JP-B-59-42864, and the like can also be mentioned.

(B) Onium salt compound As the radical initiator (b) preferable as the radical initiator used in the present invention, compounds represented by the following general formulas (1) to (3) are exemplified.

In general formula (1), Ar ¹ and Ar ² each independently represent an aryl group having 20 or less carbon atoms, which may have a substituent. Preferred substituents when this aryl group has a substituent include a halogen atom, a nitro group, an alkyl group having 12 or less carbon atoms, an alkoxy group having 12 or less carbon atoms, or a carbon atom having 12 or less carbon atoms. An aryloxy group is mentioned. (Z ² ) ⁻ represents a counter ion selected from the group consisting of halogen ion, perchlorate ion, carboxylate ion, tetrafluoroborate ion, hexafluorophosphate ion, and sulfonate ion, preferably perchloric acid Ions, hexafluorophosphate ions, and aryl sulfonate ions.

In General Formula (2), Ar ³ represents an aryl group having 20 or less carbon atoms, which may have a substituent. Preferred examples of the substituent include a halogen atom, a nitro group, an alkyl group having 12 or less carbon atoms, an alkoxy group having 12 or less carbon atoms, an aryloxy group having 12 or less carbon atoms, and 12 or less carbon atoms. Examples thereof include an alkylamino group, a dialkylamino group having 12 or less carbon atoms, an arylamino group having 12 or less carbon atoms, or a diarylamino group having 12 or less carbon atoms. (Z ³ ) ⁻ represents a counter ion having the same meaning as (Z ² ) ⁻ .

In general formula (3), R ²³ , R ²⁴ and R ²⁵ may be the same or different and each represents a hydrocarbon group having 20 or less carbon atoms which may have a substituent. Preferable substituents include a halogen atom, a nitro group, an alkyl group having 12 or less carbon atoms, an alkoxy group having 12 or less carbon atoms, or an aryloxy group having 12 or less carbon atoms. (Z ⁴ ) ⁻ represents a counter ion having the same meaning as (Z ² ) ⁻ .

  In the present invention, specific examples of onium salts that can be suitably used include those described in paragraph numbers [0030] to [0033] of JP-A-2001-133969 previously proposed by the applicant of the present application. Those described in paragraphs [0015] to [0046] of JP-A-2001-343742, Japanese Patent Application Nos. 2000-266797, 2002-148790, 2001-343742, 2002 Specific aromatic sulfonium salt compounds described in JP-A No. -6482, JP-A No. 2002-116539, JP-A No. 2004-102203, and Japanese Patent Application No. 2002-366539.

  The onium salt used in the present invention preferably has a maximum absorption wavelength of 400 nm or less, and more preferably 360 nm or less. Thus, the photosensitive lithographic printing plate can be handled under white light by setting the absorption wavelength in the ultraviolet region.

(C) Organic peroxide Preferred as the radical initiator used in the present invention (c) The organic peroxide includes almost all organic compounds having one or more oxygen-oxygen bonds in the molecule. Examples include methyl ethyl ketone peroxide, cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, acetylacetone peroxide, 1,1-bis (tertiarybutylperoxy) -3,3,5. -Trimethylcyclohexane, 1,1-bis (tertiarybutylperoxy) cyclohexane, 2,2-bis (tertiarybutylperoxy) butane, tertiarybutyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene Idroperoxide, paraffin hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, ditertiary butyl peroxide, tertiary butyl Cumyl peroxide, dicumyl peroxide, bis (tertiarybutylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-di (tertiarybutylperoxy) hexane, 2,5-xanoyl peroxide, peroxy Succinic oxide, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, meta-toluoyl peroxide, diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-2-ethoxyethyl peroxydi -Bonate, dimethoxyisopropyl peroxycarbonate, di (3-methyl-3-methoxybutyl) peroxydicarbonate, tertiary butyl peroxyacetate, tertiary butyl peroxypivalate, tertiary butyl peroxyneodecanoate, tarsha Tributyl peroxyoctanoate, tertiary butyl peroxy-3,5,5-trimethylhexanoate, tertiary butyl peroxylaurate, tertiary carbonate, 3,3'4,4'-tetra- (t -Butylperoxycarbonyl) benzophenone, 3,3'4,4'-tetra- (t-amylperoxycarbonyl) benzophenone, 3,3'4,4'-tetra- (t-hexylperoxycarbonyl) benzophenone, 3,3'4,4'-teto La- (t-octylperoxycarbonyl) benzophenone, 3,3′4,4′-tetra- (cumylperoxycarbonyl) benzophenone, 3,3′4,4′-tetra- (p-isopropylcumylperoxycarbonyl) ) Benzophenone, carbonyldi (t-butylperoxydihydrogen diphthalate), carbonyldi (t-hexylperoxydihydrogen diphthalate) and the like.

  Among them, 3,3′4,4′-tetra- (t-butylperoxycarbonyl) benzophenone, 3,3′4,4′-tetra- (t-amylperoxycarbonyl) benzophenone, 3,3′4 4'-tetra- (t-hexylperoxycarbonyl) benzophenone, 3,3'4,4'-tetra- (t-octylperoxycarbonyl) benzophenone, 3,3'4,4'-tetra- (cumylper) Peroxyesters such as (oxycarbonyl) benzophenone, 3,3′4,4′-tetra- (p-isopropylcumylperoxycarbonyl) benzophenone, di-t-butyldiperoxyisophthalate are preferred.

(D) Thio compound (d) Thio compounds preferable as the radical initiator used in the present invention include compounds having a structure represented by the following general formula (4).

In the general formula (4), R ²⁶ represents an alkyl group, an aryl group or a substituted aryl group, and R ²⁷ represents a hydrogen atom or an alkyl group. R ²⁶ and R ²⁷ represent a group of nonmetallic atoms necessary to form a 5-membered to 7-membered ring which may be bonded to each other and contain a hetero atom selected from oxygen, sulfur and nitrogen atoms.
As an alkyl group in the said General formula (4), a C1-C4 thing is preferable. As the aryl group, those having 6 to 10 carbon atoms such as phenyl and naphthyl are preferable, and as the substituted aryl group, a halogen atom such as a chlorine atom and an alkyl such as a methyl group as described above. And those substituted with an alkoxy group such as a group, a methoxy group, and an ethoxy group. R ²⁷ is preferably an alkyl group having 1 to 4 carbon atoms. Specific examples of the thio compound represented by the general formula (4) include the following compounds.

(E) Ketoxime ester compound (e) Ketoxime ester compounds preferred as the radical initiator used in the present invention include 3-benzoyloxyiminobutan-2-one, 3-acetoxyiminobutane-2-one, 3 -Propionyloxyiminobutan-2-one, 2-acetoxyiminopentan-3-one, 2-acetoxyimino-1-phenylpropan-1-one, 2-benzoyloxyimino-1-phenylpropan-1-one, Examples include 3-p-toluenesulfonyloxyiminobutan-2-one and 2-ethoxycarbonyloxyimino-1-phenylpropan-1-one.

(F) Borate compound As an example of the preferable (f) borate compound as a radical initiator used for this invention, the compound represented by following General formula (5) can be mentioned.

In the general formula (5), R ²⁸ , R ²⁹ , R ³⁰ and R ³¹ may be the same or different from each other, and each is a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted group. An alkenyl group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted heterocyclic group, wherein R ²⁸ , R ²⁹ , R ³⁰ and R ³¹ are bonded to form a cyclic structure. May be. However, at least one of R ²⁸ , R ²⁹ , R ³⁰ and R ³¹ is a substituted or unsubstituted alkyl group. (Z ⁵ ) ⁺ represents an alkali metal cation or a quaternary ammonium cation.
Examples of the alkyl group for R ^{28 to} R ³¹ include straight-chain, branched, and cyclic groups, and those having 1 to 18 carbon atoms are preferable. Specifically, methyl, ethyl, propyl, isopropyl, butyl, pentyl, hexyl, octyl, stearyl, cyclobutyl, cyclopentyl, cyclohexyl and the like are included. The substituted alkyl group includes an alkyl group as described above, a halogen atom (for example, —Cl, —Br, etc.), a cyano group, a nitro group, an aryl group (preferably a phenyl group), a hydroxy group, —COOR ³² (here R ³² represents a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, or an aryl group), —OCOR ³³ or —OR ³⁴ (where R ³³ and R ³⁴ are alkyl groups having 1 to 14 carbon atoms, or aryl. And a group having a substituent represented by the following formula.

Here, R ³⁵ and R ³⁶ independently represent a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, or an aryl group.
The aryl group of R ^{28 to} R ³¹ includes 1 to 3 ring aryl groups such as a phenyl group and a naphthyl group, and the substituted aryl group is a substitution of the above substituted alkyl group with the above aryl group. Those having a group or an alkyl group having 1 to 14 carbon atoms are included. Examples of the alkenyl group for R ^{28 to} R ³¹ include linear, branched and cyclic groups having 2 to 18 carbon atoms. Examples of the substituent of the substituted alkenyl group include those listed as the substituents of the substituted alkyl group. Examples of the alkynyl group of R ^{28 to} R ³¹ include straight chain or branched groups having 2 to 28 carbon atoms, and examples of the substituent of the substituted alkynyl group include those listed as the substituents of the substituted alkyl group. included. In addition, examples of the heterocyclic group of R ^{28 to} R ³¹ include a 5-membered ring or more, preferably a 5- to 7-membered heterocyclic group containing at least one of N, S, and O. May contain a condensed ring. Furthermore, you may have what was mentioned as a substituent of the above-mentioned substituted aryl group as a substituent. Specific examples of the compound represented by the general formula (5) are described in US Pat. Nos. 3,567,453 and 4,343,891, European Patents 109,772 and 109,773. Compounds and those shown below are mentioned.

(G) Azinium Compound Preferred as the radical initiator used in the present invention (g) As the azinium salt compound, JP-A 63-138345, JP-A 63-142345, JP-A 63-142346, JP Examples include compounds having an N—O bond described in JP-A-63-143537 and JP-B-46-42363.

(H) Metallocene compounds Preferred (h) metallocene compounds as radical initiators used in the present invention include those disclosed in JP-A-59-152396, JP-A-61-151197, JP-A-63-41484, and JP-A-2. And titanocene compounds described in JP-A No.-249 and JP-A-2-4705, and iron-arene complexes described in JP-A-1-304453 and JP-A-1-152109.

  Specific examples of the titanocene compound include di-cyclopentadienyl-Ti-di-chloride, di-cyclopentadienyl-Ti-bis-phenyl, and di-cyclopentadienyl-Ti-bis-2,3. 4,5,6-pentafluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,3,5,6-tetrafluorophen-1-yl, di-cyclopentadienyl-Ti- Bis-2,4,6-trifluorophen-1-yl, di-cyclopentadienyl-Ti-2,6-difluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,4 -Difluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2,3,4,5,6-pentafluorophen-1-yl, di-methylcyclopentadienyl-Ti- -2,3,5,6-tetrafluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2,4-difluorophen-1-yl, bis (cyclopentadienyl) -bis (2,6-difluoro-3- (pyridin-1-yl) phenyl) titanium bis (cyclopentadienyl) bis [2,6-difluoro-3- (methylsulfonamido) phenyl] titanium, bis (cyclopentadi Enyl) bis [2,6-difluoro-3- (N-butylbialoyl-amino) phenyl] titanium,

Bis (cyclopentadienyl) bis [2,6-difluoro-3- (N-butyl- (4-chlorobenzoyl) amino) phenyl] titanium, bis (cyclopentadienyl) bis [2,6-difluoro-3 -(N-benzyl-2,2-dimethylpentanoylamino) phenyl] titanium, bis (cyclopentadienyl) bis [2,6-difluoro-3- (N- (2-ethylhexyl) -4-tolyl-sulfonyl] ) Amino] phenyl) titanium, bis (cyclopentadienyl) bis [2,6-difluoro-3- (N- (3-oxaheptyl) benzoylamino) phenyl] titanium, bis (cyclopentadienyl) bis [2 , 6-Difluoro-3- (N- (3,6-dioxadecyl) benzoylamino) phenyl] titanium, bis (cyclopentadienyl) bis [2,6-difluoro-3- (trifluoromethylsulfonyl) amino] phenyl) titanium, bis (cyclopentadienyl) bis [2,6-difluoro-3- (trifluoroacetylamino) phenyl] titanium,

Bis (cyclopentadienyl) bis [2,6-difluoro-3- (2-chlorobenzoyl) amino] phenyl) titanium, bis (cyclopentadienyl) bis [2,6-difluoro-3- (4-chloro Benzoyl) amino] phenyl) titanium, bis (cyclopentadienyl) bis [2,6-difluoro-3- (N- (3,6-dioxadecyl) -2,2-dimethylpentanoylamino) phenyl] titanium, bis (Cyclopentadienyl) bis [2,6-difluoro-3- (N- (3,7-dimethyl-7-methoxyoctyl) benzoylamino) phenyl] titanium, bis (cyclopentadienyl) bis [2,6 -Difluoro-3- (N-cyclohexylbenzoylamino) phenyl] titanium and the like.

(I) Active ester compound Preferred as the radical initiator used in the present invention (i) is an imide sulfonate compound described in JP-B-62-2223, JP-B-63-14340, JP-A-59-174831. And the active sulfonates described in No. 1.

(J) Compound having carbon halogen bond Examples of the compound (j) having a carbon halogen bond which is preferable as the radical initiator used in the present invention include those represented by the following general formulas (6) to (12).

In the general formula (6), X ² represents a halogen atom, and Y ¹ represents —C (X ² ) ₃ , —NH ₂ , —NHR ³⁸ , —NR ³⁸ , —OR ³⁸ . Here, R ³⁸ represents an alkyl group, a substituted alkyl group, an aryl group, or a substituted aryl group. R ³⁷ represents —C (X ² ) ₃ , an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, or a substituted alkenyl group.

In the general formula (7), R ³⁹ is an alkyl group, a substituted alkyl group, an alkenyl group, a substituted alkenyl group, an aryl group, a substituted aryl group, a halogen atom, an alkoxy group, a substituted alkoxyl group, a nitro group or a cyano group, X ³ is a halogen atom, and n is an integer of 1 to 3.

In the general formula (8), R ⁴⁰ is an aryl group or a substituted aryl group, R ⁴¹ is a group or halogen shown below, and Z ⁶ is —C (═O) — or —C (═S). — Or —SO ₂ —, X ³ is a halogen atom, and m is 1 or 2.

R ⁴² and R ⁴³ are an alkyl group, a substituted alkyl group, an alkenyl group, a substituted alkenyl group, an aryl group or a substituted aryl group, and R ⁴⁴ is the same as R ³⁸ in the general formula (6).

In the general formula (9), R ⁴⁵ is an optionally substituted aryl group or heterocyclic group, R ⁴⁶ is a trihaloalkyl group or trihaloalkenyl group having 1 to 3 carbon atoms, and p is 1 2 or 3.

General formula (10) represents a carbonylmethylene heterocyclic compound having a trihalogenomethyl group. L ⁷ is a hydrogen atom or a substituent of the formula: CO— (R ⁴⁷ ) _q (C (X ⁴ ) ₃ ) _r , Q ² is sulfur, selenium or oxygen atom, dialkylmethylene group, alkene-1,2- An ylene group, a 1,2-phenylene group or a —N—R— group, M ⁴ is a substituted or unsubstituted alkylene group or an alkenylene group, or a 1,2-arylene group, and R ⁴⁸ is an alkyl group. A group, an aralkyl group or an alkoxyalkyl group, R ⁴⁷ is a carbocyclic or heterocyclic divalent aromatic group, X ⁴ is a chlorine, bromine or iodine atom, q = 0 and r = 1 or q = 1 and r = 1 or 2.

General formula (11) represents a 4-halogeno-5- (halogenomethyl-phenyl) -oxazole derivative. X ⁵ is a halogen atom, t is an integer of 1 to 3, s is an integer of 1 to 4, R ⁴⁹ is a hydrogen atom or a CH _{3 -t} X ⁵ _t group, and R ⁵⁰ is an s value. An unsaturated organic group which may be substituted.

General formula (12) represents a 2- (halogenomethyl-phenyl) -4-halogeno-oxazole derivative. X ⁶ is a halogen atom, v is an integer of 1 to 3, u is an integer of 1 to 4, R ⁵¹ is a hydrogen atom or a CH _3-v X ⁶ _v group, and R ⁵² is a u valence. An unsaturated organic group which may be substituted.

  Specific examples of such a compound having a carbon-halogen bond include those described in Wakabayashi et al., Bull. Chem. Soc. Japan, 42, 2924 (1969), such as 2-phenyl 4,6-bis (trichloromethyl) -S-triazine, 2- (p-chlorophenyl) -4,6-bis (trichloromethyl)- S-triazine, 2- (p-tolyl) -4,6-bis (trichloromethyl) -S-triazine, 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -S-triazine, 2 -(2 ', 4'-dichlorophenyl) -4,6-bis (trichloromethyl) -S-triazine, 2,4,6-tris (trichloromethyl) -S-triazine, 2-methyl-4,6 -Bis (trichloromethyl) -S-triazine, 2-n-nonyl-4,6-bis (trichloromethyl) -S-triazine, 2- (α, α, β-trichloroethyl) -4,6 Bis (trichloromethyl) -S- triazine. In addition, compounds described in British Patent 1388492, for example, 2-styryl-4,6-bis (trichloromethyl) -S-triazine, 2- (p-methylstyryl) -4,6-bis (trichloromethyl) -S-triazine, 2- (p-methoxystyryl) -4,6-bis (trichloromethyl) -S-triazine, 2- (p-methoxystyryl) -4-amino-6-trichloromethyl-S-triazine, etc. And compounds described in JP-A-53-133428, such as 2- (4-methoxy-naphth-1-yl) -4,6-bis-trichloromethyl-S-triazine, 2- (4-ethoxy-naphtho) 1-yl) -4,6-bis-trichloromethyl-S-triazine, 2- [4- (2-ethoxyethyl) -naphth-1-yl] -4,6-bis-trick Rumethyl-S-triazine, 2- (4,7-dimethoxy-naphth-1-yl) -4,6-bis-trichloromethyl-S-triazine), 2- (acenaphtho-5-yl) -4,6- Examples include compounds described in German Patent No. 3333724, such as bis-trichloromethyl-S-triazine, and the like.

  F.F. C. J. Schaefer et al. Org. Chem. 29, 1527 (1964), such as 2-methyl-4,6-bis (tribromomethyl) -S-triazine, 2,4,6-tris (tribromomethyl) -S-triazine, 2,4 , 6-tris (dibromomethyl) -S-triazine, 2-amino-4-methyl-6-tribromomethyl-S-triazine, 2-methoxy-4-methyl-6-trichloromethyl-S-triazine, etc. Can do. Furthermore, for example, the following compounds described in JP-A-62-258241 can be exemplified.

  Furthermore, for example, the following compounds described in JP-A-5-281728 can be mentioned.

Alternatively, M. P. Hutt, E .; F. Elslager and L. M.M. Herbel, “Journalof Heterocyclic Chemistry”, Volume 7 (N
o. 3), the following compound groups that can be easily synthesized by those skilled in the art according to the synthesis methods described on page 511 and thereafter (1970), such as the following compounds.

(K) Azo compound As the radical initiator used in the present invention, (k) As the azo compound, 2,2′-azobisisobutyronitrile, 2,2′-azobispropionitrile, 1, 1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), 4,4′-azobis (4-cyanovaleric acid), dimethyl 2,2′-azobisisobutyrate, 2,2′-azobis (2-methylpropionamide oxime) ), 2,2′-azobis [2- (2-imidazolin-2-yl) propane], 2,2′-azobis {2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxy Til] propionamide}, 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2′-azobis (N-butyl-2-methylpropionamide), 2,2 '-Azobis (N-cyclohexyl-2-methylpropionamide), 2,2'-azobis [N- (2-propenyl) -2-methylpropionamide], 2,2'-azobis (2,4,4- Trimethylpentane) and the like.

  Still more preferred examples of the radical initiator in the present invention include the above-mentioned (a) aromatic ketones, (b) onium salt compounds, (c) organic peroxides, (h) metallocene compounds, (j) carbon halogens. Examples of the compound having a bond include aromatic iodonium salts, aromatic sulfonium salts, titanocene compounds, and trihalomethyl-S-triazine compounds represented by the general formula (6). it can.

  A coinitiator may be used individually by 1 type and may use 2 or more types together. (E-2) Co-initiator is 0.1-50 mass% with respect to the total solid contained in the polymerizable composition, preferably 0.5-30 mass%, particularly preferably 5-20. It can be contained in a proportion of mass%.

(E-3) Thermal polymerization inhibitor The photosensitive composition of the present invention contains an ethylenically unsaturated bond that can be polymerized during production or storage of an image recording material to which the photosensitive composition or the photosensitive composition is applied. It is preferable to add a thermal polymerization inhibitor in order to prevent unnecessary thermal polymerization of the compound having the above.
Suitable thermal polymerization inhibitors for the present invention include phenolic hydroxyl group-containing compounds, N-oxide compounds, piperidine-1-oxyl free radical compounds, pyrrolidine-1-oxyl free radical compounds, N-nitrosophenylhydroxylamine Preferably, it is a compound selected from the group consisting of azo dyes, diazonium compounds, and cationic dyes.

Among them, the phenolic hydroxyl group-containing compound is hydroquinone, p-methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4-thiobis (3-methyl-6-t- Butylphenol), 2,2′-methylenebis (4-methyl-6-tert-butylphenol), phenolic resins, and cresol resins; N-oxide compounds are 5,5 -Dimethyl-1-pyrroline-N-oxide, 4-methylmorpholine-N-oxide, pyridine-N-oxide, 4-nitropyridine N-oxide, 3-hydroxypyridine-N-oxide, picolinic acid-N-oxide, Selected from the group consisting of nicotinic acid-N-oxide and isonicotinic acid-N-oxide Piperidine-1-oxyl free radical compounds are piperidine-1-oxyl free radical, 2,2,6,6-tetramethylpiperidine-1-oxyl free radical, 4-oxo-2,2, 6,6-tetramethylpiperidine-1-oxyl free radical, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radical, 4-acetamido-2,2,6,6-tetramethyl Piperidine-1-oxyl free radical, 4-maleimido-2,2,6,6-tetramethylpiperidine-1-oxyl free radical, and 4-phosphonoxy-2,2,6,6-tetramethylpiperidine-1-oxyl Selected from the group consisting of free radicals; pyrrolidine-1-oxyl free radical Compounds are 3-carboxyproxyl free radicals (3-carboxy-2,2,5,5-tetramethylpyrrolidine-1-oxyl free radical); N-nitrosophenylhydroxylamines are N-nitrosophenyl A compound selected from the group consisting of hydroxylamine primary cerium salt and N-nitrosophenylhydroxylamine aluminum salt; diazonium compounds are 4-diazophenyldimethylamine hydrogen sulfate, 4-diazodiphenylamine tetrafluoro A compound selected from the group consisting of borate, and hexafluorophosphate of 3-methoxy-4-diazodiphenylamine; and cationic dyes such as crystal violet, methyl violet, ethyl violet and Victor And more preferably a compound selected from the group consisting of pure blue BOH.
Furthermore, it is most preferable to use benzoquinone and its derivatives, more specifically 1,4-benzoquinone derivatives, from the viewpoint that side reactions caused by the polymerization inhibitor do not occur during synthesis.

  The addition amount of the (E-3) thermal polymerization inhibitor contained in the photosensitive composition of the present invention is preferably 0.01 to 10,000 ppm with respect to the mass after drying of the total photosensitive composition. More preferably, it is 1 to 5000 ppm, and most preferably 0.5 to 3000 ppm.

(E-4) Colorant Furthermore, when the photosensitive composition of the present invention is used in a photosensitive lithographic printing plate, a dye or pigment may be added for the purpose of coloring the photosensitive layer. Thereby, so-called plate inspection properties such as visibility after plate making and suitability for an image density measuring machine as a printing plate can be improved. As a colorant, many dyes cause a decrease in the sensitivity of the photosensitive layer. Therefore, it is particularly preferable to use a pigment as the colorant. Specific examples include pigments such as phthalocyanine pigments, azo pigments, carbon black and titanium oxide, and dyes such as ethyl violet, crystal violet, azo dyes, anthraquinone dyes, and cyanine dyes. The addition amount of the dye and the pigment is preferably about 0.5% by mass to about 5% by mass of the total composition.

(E-5) Other additives Furthermore, when the photosensitive composition of the present invention is used in a photosensitive lithographic printing plate, an inorganic filler, other plasticizers, and a photosensitive layer surface are used to improve the physical properties of the cured film. You may add well-known additives, such as a fat-sensitizing agent which can improve ink inking property.

  Examples of plasticizers include dioctyl phthalate, didodecyl phthalate, triethylene glycol dicaprylate, dimethyl glycol phthalate, tricresyl phosphate, dioctyl adipate, dibutyl sebacate, and triacetyl glycerin. 10 mass% or less can be added with respect to the total mass of the compound which has an ionic unsaturated double bond, and a binder.

Further, for the purpose of improving the film strength (printing durability), which will be described later, a UV initiator, a thermal crosslinking agent, or the like can be added to enhance the effect of heating and exposure after development.
In addition, it is also possible to provide an additive and an intermediate layer for improving the adhesion between the photosensitive layer and the support and improving the development and removal of the unexposed photosensitive layer. For example, by adding or undercoating a compound having a relatively strong interaction with the substrate, such as a compound having a diazonium structure or a phosphone compound, adhesion can be improved and printing durability can be improved. By adding or undercoating a hydrophilic polymer such as acid or polysulfonic acid, the developability of the non-image area is improved, and the stain resistance can be improved.

  In addition, when using the photosensitive composition of the present invention as a photosensitive layer of a photosensitive lithographic printing plate, from the viewpoint of sensitivity and storage stability, a compound represented by the general formula (XVIII) is used as a sensitizing dye, An initiator system in which a hexaarylbiimidazole compound and a compound comprising the general formula (I) are combined as an initiator compound is preferable, and an initiator system comprising these and (D) a polymerizable compound having an ethylenically unsaturated double bond is contained. Embodiments are particularly preferred.

(Formation of image recording material)
Various image recording materials to which the photosensitive composition of the present invention is applied can be prepared by dissolving the above-described constituents in a suitable organic solvent and applying the solution to a support.
Solvents used here include acetone, methyl ethyl ketone, 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, 3-methoxypropanol, methoxymethoxyethanol, diethylene glycol monomethyl ether, Ethylene 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, methyl lactate, lactic acid There is ethyl. These solvents can be used alone or in combination. The solid content in the coating solution is suitably 2 to 50% by mass.

The amount of the photosensitive composition applied to the support is preferably selected according to the intended use in consideration of the sensitivity of the photosensitive layer, the developability, the strength of the exposed film and the printing durability. When the coating amount is too small, the printing durability is not sufficient. On the other hand, when the amount is too large, sensitivity is lowered, exposure takes time, and development processing requires a longer time, which is not preferable. The coating amount as the photosensitive layer of the photosensitive lithographic printing plate for scanning exposure which is a preferred embodiment of the photosensitive composition of the present invention is generally about 0.1 g / m ² to about 10 g in terms of the mass after drying. A range of / m ² is suitable. More preferably from 0.5 to 5 g / m ^2.

(Support)
As the support for the image recording material to which the photosensitive composition of the present invention is applied, various supports can be used without limitation depending on the intended use, but conventionally known hydrophilic substances used for photosensitive lithographic printing plates. A sexual support is preferably used.
Such a support is preferably a dimensionally stable plate, for example, paper, paper laminated with plastic (for example, polyethylene, polypropylene, polystyrene, etc.), metal plate (for example, aluminum). , Zinc, copper, etc.), plastic films (eg, cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc.), Paper or plastic film, etc., laminated or vapor-deposited with metals as described above are included. For these purposes, if necessary, for the purpose of imparting hydrophilicity or improving strength, appropriate known physical and chemical You can give it a treatment .

  In particular, preferred supports include paper, polyester film or aluminum plate, among which dimensional stability is good, relatively inexpensive, and a surface with excellent hydrophilicity and strength is provided by surface treatment as required. An aluminum plate that can be formed is more preferable. A composite sheet in which an aluminum sheet is bonded to a polyethylene terephthalate film as described in Japanese Patent Publication No. 48-18327 is also preferable.

An aluminum plate is a metal plate mainly composed of dimensionally stable aluminum. In addition to a pure aluminum plate, an alloy plate containing aluminum as a main component and containing a trace amount of foreign elements, or aluminum (alloy) is laminated. Or it is chosen from the vapor-deposited plastic film or paper. In the following description, the above-mentioned support made of aluminum or an aluminum alloy is generically used as an aluminum support. Examples of the foreign element contained in the aluminum alloy include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, and titanium. The content of the foreign element in the alloy is 10% by mass or less. In the present invention, a pure aluminum plate is suitable, but completely pure aluminum is difficult to manufacture in terms of refining technology, and therefore may contain a slightly different element. Thus, the composition of the aluminum plate applied to the present invention is not specified, and it is a conventionally known material such as JIS A 1050, JIS A 1100, JIS A 3103, JIS A 3005, etc. Can be used as appropriate.
Moreover, the thickness of the aluminum support body used for this invention is about 0.1 mm-about 0.6 mm. This thickness can be appropriately adjusted depending on the use of the photosensitive composition of the present invention. For example, when the photosensitive composition of the present invention is applied to a photosensitive lithographic printing plate, it can be appropriately changed depending on the size of the printing press, the size of the printing plate, and the desire of the user. The aluminum support may be subjected to a support surface treatment described later as necessary. Of course, it may not be applied.

<Roughening treatment>
Examples of the surface roughening method include mechanical surface roughening, chemical etching, and electrolytic grain as disclosed in JP-A-56-28893. Furthermore, the electrochemical surface roughening method in which the surface is electrochemically roughened in hydrochloric acid or nitric acid electrolyte solution, the aluminum surface is scratched with a metal wire, the wire brush grain method, the surface of the aluminum is polished with a polishing ball and an abrasive. A mechanical graining method such as a pole grain method, a brush grain method in which the surface is roughened with a nylon brush and an abrasive, can be used, and the above roughening methods can be used alone or in combination. Among them, a method usefully used for roughening is an electrochemical method in which roughening is performed chemically in hydrochloric acid or nitric acid electrolyte, and a suitable amount of electricity at the time of anode is 50 C / dm ^{2 to} 400 C / dm ² . It is a range. More specifically, in the electrolytic solution containing from 0.1 to 50% hydrochloric acid or nitric acid, the temperature 20 to 80 ° C., for 1 second to 30 minutes, alternating at a current density of 100C / dm ² ~400C / dm ² It is preferable to perform direct current electrolysis.

  The roughened aluminum support may be chemically etched with acid or alkali. Etching agents suitably used are caustic soda, sodium carbonate, sodium aluminate, sodium metasilicate, sodium phosphate, potassium hydroxide, lithium hydroxide, and the like. Preferred ranges of concentration and temperature are 1 to 50% and 20%, respectively. ~ 100 ° C. Pickling is performed to remove dirt (smut) remaining on the surface after etching. As the acid used, nitric acid, sulfuric acid, phosphoric acid, chromic acid, hydrofluoric acid, borohydrofluoric acid and the like are used. In particular, as a method for removing smut after the electrochemical surface roughening treatment, contact with 15 to 65 mass% sulfuric acid at a temperature of 50 to 90 ° C. as described in JP-A-53-12739 is preferable. And the alkali etching method described in Japanese Patent Publication No. 48-28123. After the treatment as described above, the method condition is not particularly limited as long as the center line average roughness Ra of the treatment surface is preferably 0.2 to 0.5 μm.

<Anodizing treatment>
The aluminum support treated as described above is preferably anodized after that.
In the anodizing treatment, sulfuric acid, phosphoric acid, oxalic acid, or an aqueous solution of boric acid / sodium borate is used alone or in combination as a main component of the electrolytic bath. In this case, the electrolyte solution may of course contain at least components normally contained in at least an Al alloy plate, an electrode, tap water, groundwater and the like. Further, the second and third components may be added. Here, the second and third components are, for example, metal ions such as Na, K, Mg, Li, Ca, Ti, Al, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, and ammonium ions. Examples include cations, nitrate ions, carbonate ions, chloride ions, phosphate ions, fluorine ions, sulfite ions, titanate ions, silicate ions, borate ions and the like, and the concentration is 0 to 10,000 ppm. May be included. There are no particular limitations on the conditions of the anodizing treatment, but the treatment is preferably carried out by direct current or alternating current electrolysis at a current density of 0.1 to 40 A / m ² at 30 to 500 g / liter, a treatment liquid temperature of 10 to 70 ° C. . The thickness of the formed anodic oxide film is in the range of 0.5 to 1.5 μm. Preferably it is the range of 0.5-1.0 micrometer. The support prepared by the above treatment is treated so that the pore diameter of the micropores existing in the anodized film is in the range of 5 to 10 nm and the pore density is in the range of 8 × 10 ¹⁵ to 2 × 10 ¹⁶ pieces / m ^2. It is preferred that the conditions are selected.

A widely known method can be applied as the hydrophilic treatment on the surface of the support. As a particularly preferable treatment, a hydrophilic treatment with silicate or polyvinylphosphonic acid is performed. A film | membrane is formed by 2-40 mg / m < ² > as Si or P element amount, More preferably, it is 4-30 mg / m < ² >. The coating amount can be measured by fluorescent X-ray analysis.

  The hydrophilization treatment is carried out by applying an anodized film to an aqueous solution containing 1 to 30% by mass, preferably 2 to 15% by mass of alkali metal silicate or polyvinylphosphonic acid, and having a pH of 10 to 13 at 25 ° C. This is carried out by immersing the aluminum support on which is formed, for example, at 15 to 80 ° C. for 0.5 to 120 seconds.

As the alkali metal silicate used for the hydrophilization treatment, sodium silicate, potassium silicate, lithium silicate, or the like is used. Examples of the hydroxide used for increasing the pH of the aqueous alkali metal silicate solution include sodium hydroxide, potassium hydroxide, and lithium hydroxide. In addition, you may mix | blend alkaline-earth metal salt or Group IVB metal salt with said process liquid. Alkaline earth metal salts include nitrates such as calcium nitrate, strontium nitrate, magnesium nitrate, and barium nitrate, and water-soluble substances such as sulfate, hydrochloride, phosphate, acetate, oxalate, and borate. Salt. Group IVB metal salts include titanium tetrachloride, titanium trichloride, potassium titanium fluoride, potassium titanium oxalate, titanium sulfate, titanium tetraiodide, zirconium chloride, zirconium dioxide, zirconium oxychloride, zirconium tetrachloride, etc. Can be mentioned.

  Alkaline earth metal salts or Group IVB metal salts can be used alone or in combination of two or more. A preferable range of these metal salts is 0.01 to 10% by mass, and a more preferable range is 0.05 to 5.0% by mass. Silicate electrodeposition as described in US Pat. No. 3,658,662 is also effective. A surface obtained by combining a support subjected to electrolytic grain as disclosed in JP-B-46-27481, JP-A-52-58602, and JP-A-52-30503 with the above-described anodizing treatment and hydrophilization treatment. Processing is also useful.

(Middle layer)
In the image recording material to which the photosensitive composition of the present invention is applied, an intermediate layer (also referred to as an undercoat layer) is used for the purpose of improving adhesion between the photosensitive layer (image recording layer) and the support and stain resistance. May be provided. Specific examples of such an intermediate layer include JP-B-50-7481, JP-A-54-72104, JP-A-59-101651, JP-A-60-149491, JP-A-60-232998, JP-A-3-56177, JP-A-4-282737, JP-A-5-16558, JP-A-5-246171, JP-A-7-159983, JP-A-7-314937, JP-A-8-202025, Special Kaihei 8-320551, JP 9-34104, JP 9-236911, JP 9-269593, JP 10-69092, JP 10-115931, JP 10-161317, JP 10-260536, JP-A-10-282682, JP-A-11-84684, Japanese Patent Application No. 8-225335, Japanese Patent Application No. 8-270098, Japanese Patent Application No. 9-195863, Japanese Patent Application No. 9-195864, Japanese Patent Application No. 9-89646, Japanese Patent Application No. 9-106068, Japanese Patent Application No. 9-183834, Japanese Patent Application No. 9-264411, Japanese Patent Application No. 9 -127232, Japanese Patent Application No. 9-245419, Japanese Patent Application No. 10-127602, Japanese Patent Application No. 10-170202, Japanese Patent Application No. 11-36377, Japanese Patent Application No. 11-165661, Japanese Patent Application No. 11-284091 No., Japanese Patent Application No. 2000-14697, and the like.

(Protective layer)
When image recording is performed on an image recording material to which the photosensitive composition of the present invention is applied, since exposure is usually performed in the air, a protective layer (also referred to as an overcoat layer) is further provided on the photosensitive layer. It is preferable. In particular, when the photosensitive composition of the present invention is applied to a photosensitive lithographic printing plate, it is a preferred embodiment that such a protective layer is provided on the photosensitive layer. The protective layer prevents exposure of low molecular weight compounds such as oxygen and basic substances present in the atmosphere that hinder the image formation reaction caused by exposure in the photosensitive layer, and enables exposure in the atmosphere. To do. Therefore, the properties desired for such a protective layer are low permeability of low-molecular compounds such as oxygen, and further, transmission of light used for exposure is not substantially inhibited, and adhesion to the photosensitive layer is excellent. And it is desirable that it can be easily removed in the development process after exposure.

  Such a device relating to the protective layer has been conventionally devised and is described in detail in US Pat. No. 3,458,311 and Japanese Patent Publication No. 55-49729. As a material that can be used for the protective layer, for example, a water-soluble polymer compound having relatively excellent crystallinity is preferably used. Specifically, polyvinyl alcohol, polyvinyl pyrrolidone, acidic celluloses, gelatin, gum arabic, Water-soluble polymers such as acrylic acid are known, but among these, using polyvinyl alcohol as the main component gives the best results in terms of basic properties such as oxygen barrier properties and development removability. The polyvinyl alcohol used for the protective layer may be partially substituted with an ester, an ether and an acetal as long as it contains an unsubstituted vinyl alcohol unit for having necessary oxygen barrier properties and water solubility. Similarly, some of them may have other copolymer components. In particular, a mixture obtained by replacing polyvinyl pyrrolidone in a range of 15 to 50% by mass with respect to polyvinyl alcohol is preferable from the viewpoint of storage stability.

  Specific examples of polyvinyl alcohol include those having a hydrolysis rate of 71 to 100% and a molecular weight in the range of 300 to 2400. Specifically, Kuraray Co., Ltd. PVA-105, PVA-110, PVA-117, PVA-117H, PVA-120, PVA-124, PVA-124H, PVA-CS, PVA-CST, PVA-HC, PVA-203, PVA-204, PVA-205, PVA-210, PVA-217, PVA-220, PVA-224, PVA-217EE, PVA-217E, PVA-220E, PVA-224E, PVA-405, PVA- 420, PVA-613, L-8 and the like.

  Components of the protective layer (selection of PVA, use of additives), coating amount, and the like are selected in consideration of fogging, adhesion, and scratch resistance in addition to oxygen barrier properties and development removability. In general, the higher the hydrolysis rate of the PVA used (the higher the content of the unsubstituted vinyl alcohol unit in the protective layer), the thicker the film thickness, the higher the oxygen barrier property, which is advantageous in terms of sensitivity. However, when the oxygen barrier property is extremely increased, there arises a problem that unnecessary polymerization reaction occurs during production and raw storage, and unnecessary fogging and image line thickening occur during image exposure. In addition, adhesion to the image area and scratch resistance are extremely important in handling the plate. That is, when a hydrophilic layer made of a water-soluble polymer is laminated on an oleophilic photosensitive layer, film peeling due to insufficient adhesive force is likely to occur, and the peeled part causes defects such as poor film hardening due to inhibition of oxygen polymerization.

  On the other hand, various proposals have been made to improve the adhesion between these two layers. For example, U.S. Patent Application No. 292,501 and U.S. Patent Application No. 44,563 disclose an acrylic emulsion or a water-insoluble vinylpyrrolidone-vinyl acetate copolymer in a hydrophilic polymer mainly composed of polyvinyl alcohol. It is described that sufficient adhesiveness can be obtained by mixing 20 to 60% by mass and the like and laminating on the photosensitive layer. Any of these known techniques can be applied to the protective layer in the present invention. Such a coating method of the protective layer is described in detail in, for example, US Pat. No. 3,458,311 and JP-B-55-49729.

The image recording material to which the photosensitive composition of the present invention is applied can record an image through at least an exposure and development process. In particular, when the photosensitive composition of the present invention is applied to a photosensitive lithographic printing plate, the exposure and development processes as shown below, and other processes as necessary, are used to make a plate. .
Hereinafter, plate making when the photosensitive composition of the present invention is applied to a photosensitive lithographic printing plate will be described in detail.

As a light source for exposing the photosensitive lithographic printing plate in the present invention, a known light source can be used without limitation. A desirable wavelength of the light source is 300 nm to 1200 nm, and more preferably 350 nm to 450 nm. Specifically, it is preferable to use various lasers as the light source, and among these, a short wave laser having a wavelength of 350 nm to 430 nm is preferably used.
The exposure mechanism may be any of an internal drum system, an external drum system, a flat bed system, and the like.

  In addition, as other exposure light for the photosensitive lithographic printing plate in the present invention, ultra high pressure, high pressure, medium pressure, low pressure mercury lamp, chemical lamp, carbon arc lamp, xenon lamp, metal halide lamp, various lasers of visible and ultraviolet A lamp, a fluorescent lamp, a tungsten lamp, sunlight, etc. can also be used.

  The photosensitive lithographic printing plate in the present invention is exposed and then developed. As the developer used for such development processing, an alkaline aqueous solution having a pH of 14 or less is particularly preferred, and an alkaline aqueous solution having a pH of 8 to 12 containing an anionic surfactant is more preferably used. For example, tribasic sodium phosphate, potassium, ammonium, dibasic sodium phosphate, potassium, ammonium, sodium carbonate, potassium, ammonium, sodium bicarbonate, potassium, ammonium, sodium borate, Examples include inorganic alkaline agents such as potassium, ammonium, sodium hydroxide, ammonium, potassium and lithium. Moreover, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, Organic alkali agents such as ethyleneimine, ethylenediamine, and pyridine are also used. These alkali agents are used alone or in combination of two or more.

In the development processing of the photosensitive lithographic printing plate in the present invention, 1 to 20% by mass of an anionic surfactant is added to the developer, and more preferably 3 to 10% by mass. If the amount is too small, the developability deteriorates. If the amount is too large, the strength such as the abrasion resistance of the image deteriorates. Anionic surfactants include, for example, sodium salt of lauryl alcohol sulfate, ammonium salt of lauryl alcohol sulfate, sodium salt of octyl alcohol sulfate, such as sodium salt of isopropyl naphthalene sulfonic acid, sodium salt of isobutyl naphthalene sulfonic acid, polyoxy Higher carbon number such as sodium salt of ethylene glycol mononaphthyl ether sulfate ester, sodium salt of dodecylbenzene sulfonic acid, alkylaryl sulfonate such as sodium salt of metanitrobenzene sulfonic acid, secondary sodium alkyl sulfate, etc. Aliphatic alcohol phosphates such as alcohol sulfates, sodium salts of cetyl alcohol phosphates, eg C _{17 H 33 CON (CH 3)} CH 2 CH 2 SO 3 sulfonates of alkylamides such as Na, for example, sodium sulfosuccinate dioctyl ester, sulfonate of dibasic aliphatic esters such as sodium sulfosuccinate dihexyl ester Salts are included.

  If necessary, an organic solvent mixed with water such as benzyl alcohol may be added to the developer. As the organic solvent, those having a solubility in water of about 10% by mass or less are suitable, and preferably selected from those having 5% by mass or less. For example, 1-phenylethanol, 2-phenylethanol, 3-phenylpropanol, 1,4-phenylbutanol, 2,2-phenylbutanol, 1,2-phenoxyethanol, 2-benzyloxyethanol, o-methoxybenzyl alcohol, m -Methoxybenzyl alcohol, p-methoxybenzyl alcohol, benzyl alcohol, cyclohexanol, 2-methylcyclohexanol, 4-methylcyclohexanol, 3-methylcyclohexanol and the like can be mentioned. The content of the organic solvent is preferably 1 to 5% by mass with respect to the total mass of the developer at the time of use. The amount used is closely related to the amount of surfactant used, and it is preferable to increase the amount of anionic surfactant as the amount of organic solvent increases. This is because when the amount of the organic solvent is large and the amount of the anionic surfactant is small, the organic solvent is not dissolved, so that it is impossible to expect good developability.

Furthermore, additives such as an antifoaming agent and a hard water softening agent can be further contained as necessary. Examples of the hard water softener include Na ₂ P ₂ O ₇ , Na ₅ P ₃ O ₃ , Na ₃ P ₃ O ₉ , Na ₂ O ₄ P (NaO ₃ P) PO ₃ Na ₂ , Calgon (sodium polymetaphosphate) Such as polyphosphates, aminopolycarboxylic acids (for example, ethylenediaminetetraacetic acid, its potassium salt, its sodium salt; diethylenetriaminepentaacetic acid, its potassium salt, its sodium salt; triethylenetetraminehexaacetic acid, its potassium salt, its sodium salt Hydroxyethylethylenediaminetriacetic acid, its potassium salt, its sodium salt; nitrilotriacetic acid, its potassium salt, its sodium salt; 1,2-diaminocyclohexanetetraacetic acid, its potassium salt, its sodium salt; 1,3-diamino-2 -Propanol tetraacetic acid, its potassium salt, Sodium salt), other polycarboxylic acids (eg 2-phosphonobutanetricarboxylic acid-1,2,4, potassium salt thereof, sodium salt thereof; 2-phosphonobutanone tricarboxylic acid-2,3,4, Potassium salt, sodium salt thereof, etc., organic phosphonic acids (eg, 1-phosphonoethanetricarboxylic acid-1,2,2, potassium salt, sodium salt thereof; 1-hydroxyethane-1,1-diphosphonic acid, Potassium salt, sodium salt thereof; aminotri (methylenephosphonic acid), potassium salt thereof, sodium salt thereof and the like. The optimum amount of such a hard water softener varies depending on the hardness of the hard water used and the amount used, but is generally 0.01 to 5% by weight, more preferably in the developer at the time of use. It is made to contain in 0.01-0.5 mass%.

  Furthermore, when developing the photosensitive lithographic printing plate using an automatic developing machine, the developing solution becomes fatigued depending on the amount of processing, so that the processing capacity is restored by using a replenishing solution or a fresh developing solution. You may let them. In this case, it is preferable to replenish by the method described in US Pat. No. 4,882,246. Developers described in JP-A-50-26601, 58-54341, JP-B-56-39464, 56-42860, and 57-7427 are also preferable.

  The photosensitive lithographic printing plate thus developed is washed with water or an interface as described in JP-A Nos. 54-8002, 55-1115045, 59-58431, etc. You may post-process in the desensitizing liquid containing the rinse liquid containing an active agent etc., gum arabic, a starch derivative, etc. In the post-treatment of the photosensitive lithographic printing plate according to the invention, these treatments can be used in various combinations.

As the plate making process of the photosensitive lithographic printing plate in the present invention, the entire surface may be heated before exposure, during exposure, and between exposure and development, if necessary. By such heating, the image forming reaction in the photosensitive layer is promoted, and advantages such as improvement in sensitivity and printing durability and stabilization of sensitivity may occur. Further, for the purpose of improving the image strength and printing durability, it is also effective to subject the developed image to full post heating or full exposure.
Usually, heating before development is preferably performed under mild conditions of 150 ° C. or less. If the temperature is too high, problems such as causing an undesired curing reaction in the non-image area are caused. Very strong conditions can be used for heating after development. Usually, the heating temperature is 200 to 500 ° C. If the heating temperature after development is low, sufficient image strengthening action cannot be obtained, and if it is too high, problems such as deterioration of the support and thermal decomposition of the image area may occur.

The planographic printing plate obtained by the above processing is loaded on an offset printing machine and used for printing a large number of sheets.
As plate cleaners used for removing stains on the plate during printing, conventionally known plate cleaners for PS plates are used. For example, CL-1, CL-2, CP, CN-4, CN, CG-1, PC-1, SR, IC (made by Fuji Photo Film Co., Ltd.), etc. are mentioned.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.
<Examples 1 to 21 and Comparative Examples 1 to 9>
(Preparation of support)
An aluminum plate having a thickness of 0.3 mm was etched by being immersed in 10% by mass sodium hydroxide at 60 ° C. for 25 seconds, washed with running water, neutralized with 20% by mass nitric acid, and then washed with water. This was subjected to an electrolytic surface roughening treatment in a 1% by mass nitric acid aqueous solution using a sinusoidal alternating waveform current at an anode time electricity of 300 coulomb / dm ² . Subsequently, after dipping in a 1% by mass aqueous sodium hydroxide solution at 40 ° C. for 5 seconds and then in a 30% by mass sulfuric acid aqueous solution and desmutting at 60 ° C. for 40 seconds, the current density in a 20% by mass sulfuric acid aqueous solution was 2A / current density. At dm ² , the anodization treatment was performed for 2 minutes so that the thickness of the anodized film was 2.7 g / m ² . When the surface roughness was measured, it was 0.3 μm (Ra indication according to JISB0601).

A back coat coating solution was applied to the back surface of the substrate thus treated with a bar coater and dried at 100 ° C. for 1 minute to prepare a support provided with a back coat layer having a coating amount after drying of 70 mg / m ² . . The backcoat coating solution was prepared by adding the following additive solution to the following sol-gel reaction solution and by the method shown below.

(Sol-gel reaction solution)
Tetraethylsilicate 50 parts by weight Water 20 parts by weight Methanol 15 parts by weight Phosphoric acid 0.05 parts by weight

  When the above components were mixed and stirred, heat generation started in about 5 minutes. After reacting for 60 minutes, a backcoat coating solution was prepared by adding the following solution.

(Additive solution)
Pyrogallol formaldehyde condensation resin (molecular weight 2000) 4 parts by mass Dimethyl phthalate 5 parts by mass Fluorosurfactant 0.7 parts by mass (N-butylperfluorooctane / sulfonamidoethyl acrylate / polyoxyethylene acrylate copolymer: molecular weight 20,000)
Methanol silica sol 50 parts by mass (manufactured by Nissan Chemical Industries, Ltd., methanol 30% by mass)
800 parts by mass of methanol

(Formation of photosensitive layer)
On the thus-treated aluminum support, a photosensitive composition having the following composition was applied such that the dry coating amount was 1.3 g / m ² and dried at 80 ° C. for 2 minutes to form a photosensitive layer.

(Photosensitive composition)
1.0 g of the following addition polymerizable compound (M-1)
The following polyurethane resin binder (U-1) 1.0g

Polyurethane resin binder (U-1):
Polyurethane resin, which is a polycondensation product of the following diisocyanate and diol: 4,4'-diphenylmethane diisoisocyanate (MDI)
・ Hexamethylene diisocyanate (HMDI)
-Polypropylene glycol, mass average molecular weight 1000 (PPG1000)
・ 2,2-bis (hydroxymethyl) propionic acid (DMPA)
・ Glycerin monomethacrylate (Blemmer GLM manufactured by NOF Corporation)
[Copolymerization molar ratio (MDI / HMDI / PPG1000 / DMPA / Blemmer GLM = 80/20/22/52/26)]
Measured acid value obtained by KOH titration 0.92 meq / g
Mass average molecular weight of 60,000 determined by GPC measurement

Photopolymerization initiation system (Used compounds are listed in Table 1)
・ Sensitizing dye 0.06g
Initiator (2,2′-bis (o-chlorophenyl) -4,4 ′, 5,5′-te
0.20 g of traphenylbiimidazole)
-Compound represented by general formula (I) 0.15 g

Fluorine nonionic surfactant (F-780F) 0.03g
Thermal polymerization inhibitor 0.01g
(N-nitrosophenylhydroxylamine aluminum salt)

1.0 g of the following pigment dispersion
Methyl ethyl ketone 10g
10g of propylene glycol monomethyl ether

(Composition of pigment dispersion)
Pigment Blue 15: 6 15 parts by mass Allyl methacrylate / methacrylic acid copolymer 10 parts by mass (copolymerization molar ratio 83/17)
-Cyclohexanone 15 parts by mass-Methoxypropyl acetate 20 parts by mass-Propylene glycol monomethyl ether 40 parts by mass

(Formation of protective layer)
On this photosensitive layer, a 3% by weight aqueous solution of polyvinyl alcohol (saponification degree 98 mol%, polymerization degree 550) was applied so that the dry coating weight was 2 g / m ^2, and dried at 100 ° C. for 2 minutes for protection. A layer was formed to obtain a photosensitive lithographic printing plate.

[Sensitivity evaluation]
A Fuji step guide manufactured by Fuji Photo Film Co., Ltd. (gray scale whose transmission optical density changes discontinuously at ΔD = 0.15) is adhered to the photosensitive lithographic printing plate thus obtained, Exposure was performed with a xenon lamp through an optical filter so as to obtain a known exposure energy.
Thereafter, the film was immersed in a developer having the following composition at 25 ° C. for 10 seconds, developed, the maximum number of steps at which the image was completely removed was read, the exposure energy amount was determined, and the sensitivity was calculated (unit, mJ / cm). ² ). The smaller the amount of energy, the higher the sensitivity. For the purpose of estimating the suitability of exposure to a short-wave semiconductor laser, Kenko BP-40 was used as an optical filter, and exposure was performed with 400 nm monochromic light. The results are shown in Table 1.

[Evaluation of storage stability]
The same printing plate under the high temperature condition (60 ° C.) as the value X ₀ obtained by measuring the dot area of 50% of the exposure setting on the exposure plate on the printing plate shown in Table 1 subjected to the above sensitivity evaluation with a ccDOT manufactured by Centurfax After 3 days of storage, laser exposure was performed with exactly the same amount of light as before storage at high temperature, and development processing was performed in the same manner, and the difference (X ₃ -X ₀ ) in the halftone dot area value X ₃ of 50% of the drawing setting actually measured was obtained. . The smaller this (X ₃ −X ₀ ) value, the better the storage stability, and it can be said that a storage stability of 5 or less is good. The results of the storage stability evaluation are also shown in Table 1.

(Developer)
PH 12.0 aqueous solution with the following composition: Potassium hydroxide 0.2g
・ 1K potassium silicate 2.4g
(SiO ₂ / K ₂ O = 1.9)
・ The following compound 5.0 g
・ Ethylenediaminetetraacetic acid ・ 4Na salt 0.1g
・ Water 91.3g

  In Table 1, the structure of the general formula (I) according to the present invention used in the photopolymerization initiation system is the same as that of the exemplified compound. The structures of sensitizing dyes (D-1) to (D-3), hexaarylbiimidazole compounds, initiator compounds (I-1) to (I-4) and comparative examples are as shown below. The following (R-1) to (R-3) used in Comparative Examples are compounds outside the scope of the present invention.

As is apparent from Table 1, it was revealed that any photosensitive lithographic printing plate using the photosensitive composition of the present invention for the photosensitive layer can form an image with high sensitivity and exhibits high storage stability. On the other hand, as shown in Comparative Examples 1 to 9, when using a comparative compound with a small volume that is outside the scope of the present invention, it is possible to obtain both sensitivity and practically sufficient storage stability. could not.
It can be seen from Examples 1 to 21 that the photosensitive composition of the present invention can be applied in a wide range regardless of the main skeleton.

<Examples 22 to 39 and Comparative Examples 10 to 16>
An intermediate layer, a photosensitive layer, and a protective layer were sequentially formed on the support used in Examples 1 to 21 in the following procedure to prepare a photosensitive lithographic printing plate.
(Coating intermediate layer)
On the surface of the support, a coating solution having the following composition (A) is prepared so that the coating amount of phenylphosphonic acid is 20 mg / m ^2, and after coating at 180 rpm with a wheeler, 80 ° C. And dried for 30 seconds to form an intermediate layer.

(Intermediate layer coating solution A)
Phenylphosphonic acid 0.07g ~ 1.4g
Methanol 200g

(Coating of photosensitive layer)
On the support provided with the intermediate layer, a photosensitive composition having the following composition was prepared, applied with a wheeler so that the coating amount was 1.0 to 2.0 g / m ² , and at 100 ° C. for 1 minute. A photosensitive layer was formed by drying.

(Photosensitive composition)
Addition polymerizable compound (compound described in Table 2) 1.6 g
Binder polymer (compound described in Table 2) 2.0 g
Sensitizing dye (compound described in Table 2) 0.15 g
Initiator (compound described in Table 2) 0.2 g
Compound represented by general formula (I) (compound described in Table 2) 0.3 g
2.0 g of pigment dispersion
Thermal polymerization inhibitor 0.01g
(N-nitrosophenylhydroxylamine aluminum salt)
Fluorosurfactant 0.02g
(Dai Nippon Ink Chemical Co., Ltd., MegaFuck F-780F)
Methyl ethyl ketone 20.0g
Propylene glycol monomethyl ether 20.0g

(Composition of pigment dispersion)
Pigment Blue 15: 6 15 parts by mass Allyl methacrylate / methacrylic acid copolymer 10 parts by mass
(Copolymerization molar ratio 83/17)
-Cyclohexanone 15 parts by mass-Methoxypropyl acetate 20 parts by mass-Propylene glycol monomethyl ether 40 parts by mass

(Formation of protective layer)
On this photosensitive layer, a 3% by weight aqueous solution of polyvinyl alcohol (saponification degree 98 mol%, polymerization degree 550) was applied so that the dry coating weight was 2 g / m ^2, and dried at 100 ° C. for 2 minutes for protection. A layer was formed to obtain a photosensitive lithographic printing plate.

(Exposure of photosensitive lithographic printing plate)
The photosensitive lithographic printing plate obtained as described above was subjected to solid image exposure and 175 lines / inch by using 400 nm monochromatic light as a light source and adjusting the exposure power so that the plate surface exposure energy density was 100 μJ / cm ² . A halftone image exposure of 1 to 99% in 1% increments was performed.

(Development / plate making)
Fuji Photo Film Co., Ltd. automatic processor LP-850 was charged with the following developer and Fuji Photo Film Co., Ltd. finisher FP-2W, respectively, and exposed under the conditions of a developer temperature of 30 ° C. and a development time of 18 seconds. The plate was developed / engraved to obtain a lithographic printing plate.

(Developer)
Aqueous solution of pH 10 having the following composition: 0.1 parts by mass of monoethanolamine 1.5 parts by mass of triethanolamine 4.0 parts by mass of the compound of the following formula 1 3 compounds 0.2 parts by mass Water 91.7 parts by mass

Here, R is H or C ₄ H ₉ , and n is about 4 (average value).

  Sensitivity evaluation and storage stability evaluation were performed as in Examples 1-21.

(Addition polymerizable compound in Table 2)
(M-1): The aforementioned urethane bond-containing addition polymerizable compound (M-1)
(M-2): Pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd .; NK ester A-TMMT)
(M-3): Glycerin dimethacrylate hexamethylene diisocyanate urethane prepolymer (manufactured by Kyoeisha Chemical Co., Ltd .; UA101H)

(Binder polymer in Table 2)
(B-1): Allyl methacrylate / methacrylic acid / N-isopropylacrylamide (copolymerization molar ratio 68/12/20)
Measured acid value obtained by NaOH titration 1.12 meq / g
Mass average molecular weight 100,000 determined by GPC measurement (U-1): Polyurethane resin which is a polycondensation product of the following diisocyanate and diol. 4,4′-diphenylmethane diisoisocyanate (MDI)
・ Hexamethylene diisocyanate (HMDI)
-Polypropylene glycol, mass average molecular weight 1000 (PPG1000)
・ 2,2-bis (hydroxymethyl) propionic acid (DMPA)
・ Glycerin monomethacrylate (Blemmer GLM manufactured by NOF Corporation)
[Copolymerization molar ratio (MDI / HMDI / PPG1000 / DMPA / Blemmer GLM = 80/20/22/52/26)]
Measured acid value obtained by KOH titration 0.92 meq / g
Mass average molecular weight of 60,000 determined by GPC measurement

  As is apparent from Table 2, all of the photosensitive lithographic printing plates of Examples 22 to 39 using the photosensitive composition of the present invention as the photosensitive layer were capable of making a plate with high productivity by scanning exposure, that is, It has been found that even a very low energy exposure condition can provide an excellent lithographic printing plate. On the other hand, it was clear that Comparative Examples 10 to 14 using only the hexaarylbiimidazole compound and only the initiator compound outside the scope of the present invention did not form an image, or a practically sufficient sensitivity could not be obtained. In addition, the photosensitive lithographic printing plates of Comparative Examples 15 and 16 using a photoinitiation system in which a hexaarylbiimidazole compound and a compound that is outside the scope of the present invention are combined cannot obtain practically sufficient storage stability. It was clear.

<Examples 40 to 54 and Comparative Examples 17 to 19>
(Production of support)
A molten metal of JIS A 1050 alloy containing 99.5% or more of aluminum and Fe 0.30%, Si 0.10%, Ti 0.02%, and Cu 0.013% was subjected to cleaning treatment and cast. In the cleaning process, a degassing process was performed to remove unnecessary gases such as hydrogen in the molten metal, and a ceramic tube filter process was performed. The casting method was a DC casting method. The solidified 500 mm thick ingot was chamfered 10 mm from the surface and homogenized at 550 ° C. for 10 hours so as not to coarsen the intermetallic compound.
Next, after hot rolling at 400 ° C. and intermediate annealing at 500 ° C. for 60 seconds in a continuous annealing furnace, cold rolling was performed to obtain an aluminum rolled plate having a plate pressure of 0.30 mm. By controlling the roughness of the rolling roll, the centerline average surface roughness Ra after cold rolling was controlled to 0.2 μm. Then, it applied to the tension leveler in order to improve planarity.

Next, a surface treatment for making a lithographic printing plate support was performed.
First, in order to remove the rolling oil on the surface of the aluminum plate, degreasing treatment was carried out with a 10% sodium aluminate aqueous solution at 50 ° C. for 30 seconds, and neutralization with a 30% sulfuric acid aqueous solution at 50 ° C. for 30 seconds and smut removal treatment.
Next, in order to improve the adhesion between the support and the photosensitive layer and to provide water retention to the non-image area, a so-called graining treatment was performed to roughen the surface of the support. While maintaining an aqueous solution containing 1% nitric acid and 0.5% aluminum nitrate at 45 ° C. and flowing an aluminum web through the aqueous solution, an alternating waveform with a current density of 20 A / dm ² and a duty ratio of 1: 1 by an indirect power supply cell Then, electrolytic graining was performed by giving an anode side electric quantity of 240 C / dm ² . Thereafter, etching treatment was performed with a 10% sodium aluminate aqueous solution at 50 ° C. for 30 seconds, and neutralization and smut removal treatment were performed with a 30% sulfuric acid aqueous solution at 50 ° C. for 30 seconds.

Furthermore, in order to improve wear resistance, chemical resistance and water retention, an oxide film was formed on the support by anodic oxidation. An anodized film of 2.5 g / m ² by using a 20% sulfuric acid aqueous solution as an electrolyte at 35 ° C. and carrying out an electrolytic treatment with a direct current of 14 A / dm ² by an indirect power feeding cell while carrying an aluminum web into the electrolyte. Was made.

(Formation of photosensitive layer)
A photosensitive layer coating solution having the following composition was prepared, applied to the aluminum support obtained as described above using a wire bar, and dried at 115 ° C. for 45 seconds with a hot air dryer to form a photosensitive layer. did. The coating amount after drying was in the range of 1.2 to 1.3 g / m ² .
Further, an overcoat layer coating solution having the following composition was applied using a slide hopper, and dried at 120 ° C. for 75 seconds with a hot air drying apparatus to obtain each photosensitive lithographic printing plate for each example and comparative example. It was. The coating amount of the overcoat layer was 2.3 g / m ² .

(Photosensitive layer coating solution)
Compound having at least one addition-polymerizable ethylenically unsaturated bond (A-BPE-4, manufactured by Shin-Nakamura Chemical Co., Ltd.) 1.6 g
・ 2.0 g of the following binder polymer (B-2)
・ The following infrared absorber (IR-1) 0.15 g
-Hexaarylbiimidazole compound (o-Cl-HABI) 0.20 g
Compound represented by general formula (I) (compound described in Table 3) 0.30 g
・ Fluorine-based surfactant (Megafac F-177, manufactured by Dainippon Ink & Chemicals, Inc.) 0.01 g
・ Methyl ethyl ketone 9.0g
・ Propylene glycol monomethyl ether 8.0g
・ Methanol 10.0g

(Overcoat layer coating solution)
・ Polyvinyl alcohol 2.5g
(Saponification degree 98.5 mol%, polymerization degree 500)
・ Polyvinylpyrrolidone 0.5g
(K30, manufactured by Tokyo Chemical Industry Co., Ltd., molecular weight 40,000)
・ Nonionic surfactant 0.05g
(EMAREX NP-10, manufactured by Nippon Emulsion Co., Ltd.)
・ Ion-exchanged water 96.95g

  In addition, the compound represented by general formula (I) used in each Example is an exemplary compound according to the present invention, and the compounds (R-1) to (R-3) used in Comparative Examples are It is a compound outside the scope of the present invention described above.

(Exposure and development processing)
Each negative photosensitive lithographic printing plate obtained was exposed and developed to obtain a lithographic printing plate. Details of each process are as follows.

(exposure)
The obtained negative photosensitive lithographic printing plate was exposed with a Trendsetter 3244VFS manufactured by Creo equipped with a water-cooled 40 W infrared semiconductor laser under the conditions of an output of 9 W, an outer drum rotating speed of 210 rpm, and a resolution of 2400 dpi.

(Development processing)
After the exposure, the film was developed using an automatic processor Stablon 900N manufactured by Fuji Photo Film Co., Ltd. As the developer, a 1: 4 water diluted solution of DV-2 manufactured by Fuji Photo Film Co., Ltd. was used for both the feed solution and the replenisher solution. The temperature of the developing bath was 30 ° C. As the finisher, a 1: 1 water dilution (pH = 10.8) of FN-6 manufactured by Fuji Photo Film Co., Ltd. was used.

[Sensitivity evaluation]
The amount of energy required for recording was calculated based on the line width and laser output of the image obtained by the above exposure (with an infrared laser having a wavelength of about 830 to 850 nm) and development, the loss in the optical system, and the scanning speed. The smaller the value, the higher the sensitivity. The results are also shown in Table 3.

[Evaluation of storage stability]
The photosensitive material before laser exposure is left under high humidity conditions (45 ° C., humidity 75%) for 3 days, and then the stored photosensitive material is laser-exposed in the same manner as described above to calculate the amount of energy required for recording. The energy ratio before and after high humidity storage (energy after high temperature storage / energy before high temperature storage) was determined. The energy ratio of 1.1 or less is preferable for production and it can be said that the storage stability is also good. The results are also shown in Table 3.

  As is apparent from Table 3, the photosensitive lithographic printing plates of Examples 40 to 54 using the compound represented by the general formula (I) according to the present invention are comparative examples using a compound outside the scope of the present invention. It was found that the storage stability was superior to that of photosensitive lithographic printing plates of 17-19.

Claims (4)

(A) a mercapto compound represented by the following general formula (I) and having a volume of 215 ³ or more,
A-SH (I)
(In general formula (I), A represents a heterocyclic compound which may have a substituent.)
(B) a hexaarylbiimidazole compound,
(C) a sensitizing dye, and (D) a polymerizable compound having an ethylenically unsaturated double bond,
A photosensitive composition comprising:   The photosensitive composition as described in (1) above, wherein A in the mercapto compound represented by the general formula (I) is a nitrogen-containing five-membered ring.   An image recording method comprising performing scanning exposure on an image recording material having a photosensitive layer containing the photosensitive composition according to claim 1 on a support using a laser light source of 350 to 430 nm.   A photosensitive lithographic printing plate having a support and a photosensitive layer containing the photosensitive composition according to claim 1.