JP2007025328A - Photopolymerizable composition, photosensitive lithographic printing original plate, and method for making lithographic printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photopolymerizable composition having high sensitivity and excellent in printing durability and storage stability, a photosensitive lithographic printing plate and a method for making a lithographic printing plate. <P>SOLUTION: The photopolymerizable composition contains an addition-polymerizable ethylenic double bond-containing compound, a photoinitiator, a sensitizing dye and a bromine compound having a molecular weight of 500-2,000 represented by formula (1): R-(O(C=O)-CBr<SB>3</SB>)<SB>n</SB>, wherein R represents an alkyl group, an alkenyl group, an alicyclic hydrocarbon group, an aryl group or a heterocyclic group, n is an integer of 1-4, and when n is 2-4, the molecular weight of the bromine compound represented by the formula is confined such that a numeric value obtained by dividing the molecular weight by the total number of tribromoacetyloxy groups in a molecule is made ≥500. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a photosensitive composition and a photosensitive lithographic printing plate, and more particularly to a photosensitive composition and a photosensitive lithographic printing plate that have high sensitivity and excellent printing durability.

  Generally, in a lithographic printing plate, after image exposure, an exposed portion is cured and an unexposed portion is dissolved and removed, followed by washing with water and finisher gum treatment to obtain a lithographic printing plate. In recent years, in order to obtain high resolving power and sharpness, a method for producing a lithographic printing plate by performing digital exposure with a laser beam based on image information and developing it has been studied. For example, a system for producing a lithographic printing plate by modulating an exposure light source by an image signal transmitted through a communication line, an output signal from an electronic plate making system, an image processing system, etc., and performing direct scanning exposure on a photosensitive material. It is.

  However, a conventional lithographic printing plate material using a diazo resin has a problem that it is difficult to achieve spectral sensitization and high sensitivity in accordance with the oscillation wavelength of laser light by digital exposure. In recent years, a lithographic printing plate material having a photopolymerizable photosensitive layer containing a photopolymerization initiator has been attracting attention for digital exposure using laser light because it can achieve high sensitivity suitable for laser light. A CTP (Computer To Plate) plate material for recording digital data with this laser light source is required to have high sensitivity in order to shorten the recording time. In addition, printing materials having printing durability are required in many printing fields including newspaper printing and commercial printing such as advertisements.

  In order to achieve high sensitivity, means utilizing photo radical polymerization has been studied for a long time, and the use of an s-triazine compound having a trichloromethyl group as a photopolymerization initiator (for example, Patent Document 1, Patent Reference 2 and Patent Reference 3), use of iron arene complex compound and peroxide as photopolymerization initiator (for example, refer to Patent Document 4), monoalkyltriarylborate compound as photopolymerization initiator. Use (for example, refer to Patent Document 5, Patent Document 6, and Patent Document 7), use of a titanocene compound as a photopolymerization initiator (for example, refer to Patent Document 8 and Patent Document 9), etc. are proposed. It had been. However, these techniques have insufficient sensitivity.

  On the other hand, for the purpose of improving sensitivity, a technique in which a tertiary amino group is introduced into a monomer (addition polymerizable ethylenic double bond-containing monomer) structure and a trihalogenated methyl-s-triazine compound is used in combination ( For example, see Patent Document 10), a tertiary amino group is introduced into the monomer (ethylenic double bond-containing monomer capable of addition polymerization) structure, and in addition to the trihalogenated methyl-s-triazine compound, titanocene Techniques using metallocene compounds such as these (for example, see Patent Document 11) have been proposed. However, although these techniques have improved sensitivity, the printing durability is insufficient.

  Furthermore, for the purpose of improving printing durability, a technique (see Patent Document 11) in which a bromine compound is used in combination with a photopolymerization initiator composition has been proposed, but the storage stability is still insufficient.

Therefore, when various studies were made on these bromine compounds, surprisingly, light having excellent sensitivity, printability, and storage stability was obtained by using a bromine compound having a specific structure and having a specific range of molecular weight. A polymer composition was obtained.
Japanese Patent Laid-Open No. 48-36281 JP 54-74887 A JP-A 64-35548 JP 59-219307 A Japanese Patent Laid-Open No. Sho 62-150242 JP-A-62-143044 JP-A 64-35548 JP 63-41483 A JP-A-2-291 JP-A-1-105238 JP-A-2-127404

  The present invention has been made in view of the above problems, and its purpose is to provide a photopolymerizable composition, a photosensitive lithographic printing plate, and a method for producing a lithographic printing plate that are highly sensitive and excellent in printing durability and storage stability. It is to provide.

  The above object of the present invention is achieved by the following configurations.

(Claim 1)
A photopolymerizable composition comprising an ethylenic double bond-containing compound capable of addition polymerization, a photopolymerization initiator, a sensitizing dye, and a bromine compound having a molecular weight of 500 to 2000 represented by the following general formula (1): object.

Formula (1) R- (O (C = O) -CBr 3) n
[Wherein, R represents an alkyl group, an alkenyl group, an alicyclic hydrocarbon group, an aryl group, or a heterocyclic group. n is an integer of 1-4. However, when n is 2 to 4, the molecular weight of the bromine compound represented by the general formula (1) is 500 or more divided by the total number of tribromoacetyloxy groups in the molecule. ]
(Claim 2)
The photopolymerizable composition according to claim 1, wherein the photopolymerizable composition contains an iron arene compound or a titanocene compound as a photopolymerization initiator.

(Claim 3)
The photopolymerizable composition according to claim 1 or 2, comprising a sensitizing dye represented by the following general formula (2).

[Wherein R ¹ , R ² , R ³ and R ⁴ each represent a hydrogen atom or a substituent, R ^a and R ^b each represent an alkyl group, and X represents a substituent. ]
(Claim 4)
A photosensitive lithographic printing plate precursor comprising a photopolymerizable photosensitive layer containing the photopolymerizable composition according to any one of claims 1 to 3 on a support.

(Claim 5)
A method for producing a lithographic printing plate, comprising producing the photosensitive lithographic printing plate precursor according to claim 4 by scanning and recording imagewise with a laser light source having a wavelength of 350 to 450 nm.

  INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a photopolymerizable composition having high sensitivity and excellent printing durability and storage stability, and a method for producing a photosensitive lithographic printing plate and a lithographic printing plate.

  Details of the photopolymerizable composition of the present invention will be described below.

  First, the bromine compound represented by the general formula (1) will be described.

  The bromine compound represented by the general formula (1) has a molecular weight of 500 or more and 2000 or less, and when n is an integer of 2 to 4, the molecular weight of the bromine compound is divided by the total number of tribromoacetyloxy groups in the molecule. Which is 500 or more.

  Examples of the substituent represented by R include an alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, tert-butyl group, hexyl group, octyl group, dodecyl group, pentadecyl group, stearyl group, Behenyl group, 2-methylmyristyl group, 2-octyldodecyl group, etc.), alkenyl group (eg, vinyl group, allyl group, hexadecenyl group, oleyl group, eicosenyl group, etc.), alicyclic hydrocarbon group (eg, cyclohexane) Propyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, adamantyl group, cyclopentenyl group, cyclohexenyl group, cycloheptenyl group, etc.), aryl group (for example, phenyl group, naphthyl group, etc.), complex A ring group (for example, furyl group, thienyl group, pyridyl group, A diyl group, a pyrimidyl group, a pyrazyl group, a triazyl group, an imidazolyl group, a pyrazolyl group, a thiazolyl group, a benzoimidazolyl group, a benzoxazolyl group, a quinazolyl group, a phthalazyl group, a pyrrolidyl group, an imidazolidyl group, a morpholyl group, an oxazolidyl group, etc. Can be mentioned.

  The substituent represented by R may further have a substituent. Examples of the substituent include an alkyl group, an alkenyl group, an aliphatic hydrocarbon group, an aryl group, a heterocyclic group, an alkynyl group (ethynyl, propargyl, etc.). ), Alkoxy groups (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy groups (for example, cyclopentyloxy group, cyclohexyloxy group, etc.) , Aryloxy groups (for example, phenoxy group, naphthyloxy group, etc.), alkylthio groups (for example, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio groups (for example, Cyclopentylthio group, cyclohexylthio group ), Arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxy Carbonyl group (for example, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group) Octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.) Acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyloxy group , Ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonyl) Amino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, Decylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group) Octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylureido group, pentyl) Ureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminourei Group), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.) Alkylsulfonyl groups (eg, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl groups (phenylsulfonyl group, naphthylsulfonyl group, 2-pyridyl group) Sulfonyl group, etc.), amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino) , Dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, etc.), halogen atom (eg, fluorine atom, chlorine atom, bromine atom etc.), fluorinated hydrocarbon group (eg, fluoromethyl group, trifluoromethyl) Group, pentafluoroethyl group, pentafluorophenyl group, etc.), cyano group, nitro group, hydroxy group, mercapto group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.) , Etc. R may further have a condensed ring.

  Of the substituents represented by R, an alkyl group, an alkenyl group, and an alicyclic hydrocarbon group are preferable.

  Hereinafter, although the specific example of a compound represented by General formula (1) is given, this invention is not limited to these. When the compound has an asymmetric carbon center, it may be either R-form / S-form, or a mixture of both.

  Although the compounding quantity of the bromine compound represented by these General formula (1) is not specifically limited, Preferably, it is 0.1-20 mass parts with respect to 100 mass parts of photopolymerizable compositions.

  The photopolymerization initiator that can be preferably used in combination with the bromine compound represented by the general formula (1) according to the present invention will be described.

  Photopolymerization initiators include halides (α-haloacetophenones, trichloromethyltriazines, etc.), azo compounds, aromatic carbonyl compounds (benzoin esters, ketals, acetophenones, o-acyloxyiminoketones, acylphosphines) Oxides), hexaarylbisimidazole compounds, peroxides, iron arene compounds, titanocene compounds, and the like.

  As the peroxide, organic peroxides described in JP-A Nos. 59-1504 and 61-240807 can be used. Specific compounds include ketone peroxides such as methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, cyclohexanone peroxide, methylcyclohexanone peroxide, methylcyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide; Oxide, propionyl peroxide, i-butyl peroxide, octanoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, decanoyl peroxide, uraroyl peroxide, benzoyl peroxide, benzoyl peroxide, p-chloro Benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, acetylcyclohexanesulfonyl peroxide Diacyl peroxides such as t-butyl hydroperoxide, cumene hydroperoxide, di-i-propylbenzene hydroperoxide, p-methane hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide Hydroperoxides such as 1,1,3,3-tetramethylbutyl hydroperoxide; di-t-butyl peroxide, t-butylcumyl peroxide, 1,3-bis (t-butylperoxy-i -Propyl) benzene, 2,5-dimethyl-2,5-di (t-butyl) peroxy-3,3,5-trimethylcyclohexane, butyl-4,4'-bis (t-butylperoxy) butane, etc. Peroxyketals; t-butyl peroxyacetate, t-butyl peroxy-i-butyle T-butyl peroxyoctoate, t-butylperoxypivalate, t-butylperoxyneodecanate, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxybenzoate Alkyl peresters such as di-t-butylperoxyphthalate, t-butylperoxyisophthalate, t-butylperoxylaurate, 2,5-dimethyl-2,5-dibenzoylperoxyhexane; 2-ethylhexyl peroxydicarbonate, di-i-propyl peroxydicarbonate, di-sec-butyl peroxycarbonate, dipropyl peroxydicarbonate, dimethoxy-i-propyl peroxydicarbonate, di-3-methoxybutyl Peroxydicarbonate, di-2-e Examples include peroxycarbonates such as toxiethylperoxydicarbonate and bis- (4-t-butylcyclohexyl) peroxydicarbonate; water-soluble peroxides typified by oxalic acid peroxide.

  Preferably, an organic peroxide having the following structure can be used.

  The iron arene compound that can be preferably used in the present invention is a compound in which a π electron of an aromatic hydrocarbon compound, an aromatic heterocyclic compound or an unsaturated compound and an iron ion are π-bonded, and is not particularly limited. The thing of the following structure is mentioned.

  The titanocene compound that can be preferably used in the present invention is not particularly limited, and can be appropriately selected from various titanocene compounds described in, for example, JP-A Nos. 59-152396 and 61-151197. More specifically, dicyclopentadienyl-Ti-dichloride, dicyclopentadienyl-Ti-bis-phenyl, dicyclopentadienyl-Ti-bis-2,3,4,5,6-pentafluoro Pheni-1-yl, dicyclopentadienyl-Ti-bis-2,3,5,6-tetrafluorophen-1-yl, dicyclopentadienyl-Ti-bis-2,4,6-trifluoro Phen-1-yl, dicyclopentadienyl-Ti-bis-2,6-difluorophen-1-yl, dicyclopentadienyl-Ti-bis-2,4-difluorophen-1-yl, dimethylpenta Dienyl-Ti-bis-2,3,4,5,6-pentafluorophen-1-yl, dimethylpentadienyl-Ti-bis-2,3,5,6-tetrafluorophen-1- Dimethylpentadienyl-Ti-bis-2,6-difluorophen-1-yl, dicyclopentadienyl-Ti-bis-2,6-difluoro-3- (pyr-1-yl) -pheny 1-yl (hereinafter referred to as Ti-1) may be mentioned. Among these, Ti-1 having the following structure is particularly preferable.

  As the photopolymerization initiator, onium salts such as iodonium salts, sulfonium salts, phosphonium salts, and stannonium salts can be used. That is, various onium compounds described in JP-B-55-39162, JP-A-59-14023, and “Macromolecules, Vol. 10, page 1307 (1977)” can be used. As the iodonium salt, it is also preferable to use a diaryl iodonium salt.

  Examples of the onium salt include diphenyliodonium salt, ditolyliodonium salt, phenyl (p-methoxyphenyl) iodonium salt, bis (m-nitrophenyl) iodonium salt, bis (pt-butylphenyl) iodonium salt, bis ( p-cyanophenyl) iodonium salts such as chloride, bromide, boron tetrafluoride, boron hexafluoride, phosphorus hexafluoride, arsenic hexafluoride, antimony hexafluoride, perchlorate, benzenesulfone Acid salts, p-toluene sulfonate, p-trifluoromethylbenzene sulfonate, butyl triphenyl boron salt and the like are also included.

  In the present invention, 2,4,5-triarylimidazole dimer can also be used. The following structures described in JP-A Nos. 55-127550 and 60-202437 are preferable.

  Although the compounding quantity of these photoinitiators is not specifically limited, Preferably, it is 0.1-20 mass parts with respect to 100 mass parts of photopolymerizable compositions. The blending ratio of the bromine compound represented by the general formula (1) and the photopolymerization initiator is preferably in the range of 1: 100 to 100: 1 in terms of molar ratio.

(Sensitizing dye)
When laser light is used as the light source, a spectral sensitizing dye is preferably added to the photosensitive layer. It is preferable to use a dye having an absorption maximum wavelength in the vicinity of the wavelength of the light source.

  Examples of compounds for wavelength sensitization from visible light to near infrared include cyanine, phthalocyanine, merocyanine, porphyrin, spiro compound, ferrocene, fluorene, fulgide, imidazole, perylene, phenazine, phenothiazine, polyene, azo compound, diphenylmethane, triphenyl Ketone alcohol borate complexes such as methane, polymethine acridine, coumarin, coumarin derivatives, ketocoumarin, quinacridone, indigo, styryl, pyrylium compounds, pyromethene compounds, pyrazolotriazole compounds, benzothiazole compounds, barbituric acid derivatives, thiobarbituric acid derivatives, etc. Further, European Patent No. 568,993, U.S. Pat. No. 4,508,811, No. 5,227,227, JP-A-2001-1252. 5 discloses, compounds described in JP-A 11-271969 Patent Publication also used.

  Next, the combination of the bromine compound represented by the general formula (1) and the photopolymerization initiator used in the present invention can obtain a preferable effect, and the dye having an absorption maximum at 350 nm or more and 450 nm or less includes JP 2000-98605, JP 2000-147663, JP 2000-206690, JP 2000-258910, JP 2001-42524, JP 2001-100412, JP 2005-18012. Etc. are preferred. More preferably, it is a dye represented by the general formula (2).

In the general formula (2), R ¹ , R ² , R ³ and R ⁴ each represent a hydrogen atom or a substituent. Examples of the substituent include the same groups as those that can be substituted for the group represented by R in the general formula (1). These substituents may be further substituted with the above substituents. A plurality of adjacent groups out of R ¹ , R ² , R ³ and R ⁴ may be bonded to each other to form a ring.

R ^{1 to} R ⁴ are preferably a hydrogen atom, an alkyl group, an acyl group, a halogen atom, a fluorinated hydrocarbon group, an alkoxycarbonyl group or a cyano group, more preferably a hydrogen atom, an alkyl group or a fluorinated hydrocarbon group. .

R ^a and R ^b each represents an alkyl group. These may further have a substituent, and specific examples of the substituent include the same groups as the substituents represented by R described above. R ^a and R ^b may be bonded to each other to form a ring.

  Specific examples of the substituent represented by X include the same groups as the substituents represented by R described above. An aryl group, a heterocyclic group, a carbonyl group, an alkyloxycarbonyl group, a cycloalkyloxycarbonyl group, and a carbamoyl group are preferable, a heterocyclic group, an alkyloxycarbonyl group, and a cycloalkyloxycarbonyl group are more preferable. Are an alkyloxycarbonyl group and a cycloalkyloxycarbonyl group.

  Hereinafter, although the specific example of a sensitizing dye represented by General formula (2) is given, this invention is not limited to these. Further, when these are compounds having a plurality of asymmetric carbon centers, they may be either R-form / S-form, or a mixture of both.

  Although the compounding quantity of these sensitizing dyes is not specifically limited, Preferably, it is 0.01-50 mass parts with respect to 100 mass parts of photopolymerizable compositions, More preferably, it is 0.1-30 mass parts.

  The photopolymerizable composition of the present invention preferably contains an ethylenic double bond-containing compound capable of addition polymerization.

  The compound having an ethylenic double bond capable of addition polymerization according to the present invention includes an ethylenic double bond capable of addition polymerization in a molecule generally used in general radical polymerizable monomers and UV curable resins. Plural polyfunctional monomers and polyfunctional oligomers can be used. The compound is not limited, but preferred examples thereof include 2-ethylhexyl acrylate, 2-hydroxypropyl acrylate, glycerol acrylate, tetrahydrofurfuryl acrylate, phenoxyethyl acrylate, nonylphenoxyethyl acrylate, tetrahydrofurfuryloxyethyl acrylate, tetrahydrofurfur. Monofunctional acrylic esters such as furyloxyhexanolide acrylate, acrylate of ε-caprolactone adduct of 1,3-dioxane alcohol, 1,3-dioxolane acrylate, or these acrylates into methacrylate, itaconate, crotonate, maleate Alternative methacrylic acid, itaconic acid, crotonic acid, maleic acid ester; for example, ethylene glycol diacrylene , Triethylene glycol diacrylate, pentaerythritol diacrylate, hydroquinone diacrylate, resorcin diacrylate, hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, dipentylate of hydroxypentylate neopentyl glycol, neopentyl Diacrylate of glycol adipate, Diacrylate of ε-caprolactone adduct of neopentyl glycol hydroxypivalate, 2- (2-hydroxy-1,1-dimethylethyl) -5-hydroxymethyl-5-ethyl-1,3- Dioxane diacrylate, tricyclodecane dimethylol acrylate, ε-caprolactone adduct of tricyclodecane dimethylol acrylate, 1 Difunctional acrylates such as diacrylate of diglycidyl ether of 6-hexanediol, or methacrylic acid, itaconic acid, crotonic acid, maleic acid ester in which these acrylates are replaced with methacrylate, itaconate, crotonate, maleate; Methylolpropane triacrylate, ditrimethylolpropane tetraacrylate, trimethylolethane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexaacrylate Ε-caprolactone adduct, pyrogallol triacrylate, Polyfunctional acrylic acid esters such as lopionic acid / dipentaerythritol triacrylate, propionic acid / dipentaerythritol tetraacrylate, hydroxypivalylaldehyde-modified dimethylolpropane triacrylate, or these acrylates to methacrylate, itaconate, crotonate, maleate Examples thereof include methacrylic acid, itaconic acid, crotonic acid, maleic acid ester and the like.

  Prepolymers can also be used as described above. Examples of the prepolymer include compounds as described below, and a prepolymer obtained by introducing acrylic acid or methacrylic acid into an oligomer having an appropriate molecular weight and imparting photopolymerizability can be suitably used. These prepolymers may be used alone or in combination of two or more, and may be used by mixing with the above-mentioned monomers and / or oligomers.

  Examples of prepolymers include adipic acid, trimellitic acid, maleic acid, phthalic acid, terephthalic acid, hymic acid, malonic acid, succinic acid, glutaric acid, itaconic acid, pyromellitic acid, fumaric acid, glutaric acid, pimelic acid, Polybasic acids such as sebacic acid, dodecanoic acid, tetrahydrophthalic acid, and ethylene glycol, propylene glycol, diethylene glycol, propylene oxide, 1,4-butanediol, triethylene glycol, tetraethylene glycol, polyethylene glycol, glycerin, trimethylol Polyester acrylate in which (meth) acrylic acid is introduced into a polyester obtained by combining polyhydric alcohols such as propane, pentaerythritol, sorbitol, 1,6-hexanediol, 1,2,6-hexanetriol For example, bisphenol A, epichlorohydrin, (meth) acrylic acid, and epoxy acrylates in which (meth) acrylic acid is introduced into an epoxy resin, such as phenol novolac, epichlorohydrin, (meth) acrylic acid; ethylene glycol, adipic acid, Tolylene diisocyanate, 2-hydroxyethyl acrylate, polyethylene glycol, tolylene diisocyanate, 2-hydroxyethyl acrylate, hydroxyethyl phthalyl methacrylate, xylene diisocyanate, 1,2-polybutadiene glycol, tolylene diisocyanate, 2-hydroxyethyl acrylate, tri Like methylolpropane, propylene glycol, tolylene diisocyanate, 2-hydroxyethyl acrylate, Urethane acrylate in which (meth) acrylic acid is introduced into a urethane resin; for example, silicone resin acrylates such as polysiloxane acrylate, polysiloxane diisocyanate, 2-hydroxyethyl acrylate; and other (meth) acryloyl groups are introduced into oil-modified alkyd resins And prepolymers such as alkyd-modified acrylates and spirane resin acrylates.

  The photosensitive composition of the present invention includes a phosphazene monomer, triethylene glycol, isocyanuric acid EO (ethylene oxide) modified diacrylate, isocyanuric acid EO modified triacrylate, dimethylol tricyclodecane diacrylate, trimethylolpropane benzoic acid benzoate. Addition-polymerizable oligomers and prepolymers having monomers such as acid esters, alkylene glycol type acrylic acid-modified, urethane-modified acrylates, and structural units formed from the monomers can be contained.

  Furthermore, examples of the ethylenic monomer that can be used in combination with the present invention include a phosphoric ester compound containing at least one (meth) acryloyl group. The compound is not particularly limited as long as it is a compound in which at least part of the hydroxyl group of phosphoric acid is esterified and has a (meth) acryloyl group.

  In addition, JP 58-212994, 61-6649, 62-46688, 62-48589, 62-173295, 62-187092, 63-67189, JP-A-1 The compounds described in No. 244891 etc. can be mentioned, and further, “11290 Chemical Products”, Chemical Industry Daily, pages 286-294, “UV / EB Curing Handbook (Raw Materials)” Polymer Publication The compounds described in Kaikai, pages 11 to 65 can also be suitably used. Among these, compounds having two or more acrylic groups or methacryl groups in the molecule are preferred in the present invention, and those having a molecular weight of 10,000 or less, more preferably 5,000 or less are desirable.

  In the present invention, it is preferable to use an addition-polymerizable ethylenic double bond-containing monomer containing a tertiary amino group in the molecule. Although there is no particular limitation on the structure, a tertiary amine compound having a hydroxyl group modified with glycidyl methacrylate, methacrylic acid chloride, acrylic acid chloride or the like is preferably used. Specifically, polymerizable compounds described in JP-A-1-165613 and 1-203413 are preferably used.

  Further, in the present invention, a reaction product of a polyhydric alcohol containing a tertiary amino group in the molecule, a diisocyanate compound, and a compound containing an ethylenic double bond capable of addition polymerization with a hydroxyl group in the molecule is used. Is preferred.

  Examples of the polyhydric alcohol containing a tertiary amino group in the molecule include triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N-butyldiethanolamine, Nt-butyldiethanolamine, N, N-di (hydroxyethyl) aniline, N, N, N ', N'-tetra-2-hydroxypropylethylenediamine, p-tolyldiethanolamine, N, N, N', N'-tetra-2-hydroxyethylethylenediamine N, N-bis (2-hydroxypropyl) aniline, allyldiethanolamine, 3- (dimethylamino) -1,2-propanediol, 3-diethylamino-1,2-propanediol, N, N-di ( Propyl) amino-2,3-propanediol, N, N-di (i-propyl) Amino-2,3-propanediol, 3- (N-methyl--N- benzylamino) -1,2-propanediol - but Le etc., without limitation.

  Examples of the diisocyanate compound include butane-1,4-diisocyanate, hexane-1,6-diisocyanate, 2-methylpentane-1,5-diisocyanate, octane-1,8-diisocyanate, 1,3-diisocyanate methyl-cyclohexanone. 2,2,4-trimethylhexane-1,6-diisocyanate, isophorone diisocyanate, 1,2-phenylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene-2,4-diisocyanate, tolylene- 2,5-diisocyanate, tolylene-2,6-diisocyanate, 1,3-di (isocyanatomethyl) benzene, 1,3-bis (1-isocyanato-1-methylethyl) benzene, and the like. In Not a constant.

  Examples of the compound containing an ethylenic double bond capable of addition polymerization with a hydroxyl group in the molecule include the following compounds such as MH-1 to MH-13, but are not limited thereto.

  Preferable examples include 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxypropylene-1,3-dimethacrylate, 2-hydroxypropylene-1-methacrylate-3-acrylate, and the like.

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

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

M-1: Reaction product of triethanolamine / hexane-1,6-diisocyanate / 2-hydroxyethyl methacrylate (1/3/3 mol) M-2: triethanolamine / isophorone diisocyanate / 2-hydroxyethyl acrylate ( 1/3/3 mol) of reaction product M-3: N-butyldiethanolamine / 1,3-bis (1-isocyanato-1-methylethyl) benzene / 2-hydroxypropylene-1-methacrylate-3- Reaction product of acrylate (1/2/2 mol) M-4: N-butyldiethanolamine / 1,3-di (isocyanatomethyl) benzene / 2-hydroxypropylene-1-methacrylate-3-acrylate (1 / 2/2 mol) of reaction product M-5: N-methyldiethanolamine / tolylene- Reaction product of 2,4-diisocyanate / 2-hydroxypropylene-1,3-dimethacrylate (1/2/2 mol) Besides these, acrylates described in JP-A-1-105238 and JP-A-2-127404 Alkyl acrylate can be used.

  The photopolymerizable composition of the present invention includes a bromine compound of the general formula (1), the photopolymerization initiator, a sensitizing dye of the general formula (2), and the ethylenic double bond-containing compound. A molecular binder may be contained.

  Examples of the polymer binder include acrylic polymer, polyvinyl butyral resin, polyurethane resin, polyamide resin, polyester resin, epoxy resin, phenol resin, polycarbonate resin, polyvinyl butyral resin, polyvinyl formal resin, shellac, and other natural resins. Can also be used. Two or more of these may be used in combination. A vinyl copolymer obtained by copolymerization of acrylic monomers is preferred.

  Furthermore, the copolymer composition of the polymer binder is preferably a copolymer of (a) a carboxyl group-containing monomer, (b) a methacrylic acid alkyl ester or an acrylic acid alkyl ester.

  Specific examples of the carboxyl group-containing monomer include α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride and the like. In addition, carboxylic acids such as phthalic acid and 2-hydroxymethacrylate half ester are also preferable.

  Specific examples of alkyl methacrylates and alkyl esters include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate. , Decyl methacrylate, undecyl methacrylate, dodecyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonyl acrylate, acrylic In addition to unsubstituted alkyl esters such as decyl acid, undecyl acrylate and dodecyl acrylate, cyclic alkyl esters such as cyclohexyl methacrylate and cyclohexyl acrylate Substituted alkyl esters such as benzyl methacrylate, 2-chloroethyl methacrylate, N, N-dimethylaminoethyl methacrylate, glycidyl methacrylate, benzyl acrylate, 2-chloroethyl acrylate, N, N-dimethylaminoethyl acrylate, and glycidyl acrylate Also mentioned.

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

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

  2) Monomers having an aliphatic hydroxyl group: For example, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, N-methylol acrylamide, N-methylol methacrylamide, 4-hydroxybutyl methacrylate, 5-hydroxypentyl acrylate, 5-hydroxypentyl methacrylate , 6-hydroxyhexyl acrylate, 6-hydroxyhexyl methacrylate, N- (2-hydroxyethyl) acrylamide, N- (2-hydroxyethyl) methacrylamide, hydroxyethyl vinyl ether and the like.

  3) Monomer having an aminosulfonyl group: for example, m- (or p-) aminosulfonylphenyl methacrylate, m- (or p-) aminosulfonylphenyl acrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- (p -Aminosulfonylphenyl) acrylamide and the like.

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

  5) Acrylamide or methacrylamide: For example, acrylamide, methacrylamide, N-ethylacrylamide, N-hexylacrylamide, N-cyclohexylacrylamide, N-phenylacrylamide, N- (4-nitrophenyl) acrylamide, N-ethyl-N- Phenylacrylamide, N- (4-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide and the like.

  6) Monomers containing fluorinated alkyl groups: for example, trifluoroethyl acrylate, trifluoroethyl methacrylate, tetrafluoropropyl methacrylate, hexafluoropropyl methacrylate, octafluoropentyl acrylate, octafluoropentyl methacrylate, heptadecafluorodecyl methacrylate, N- Butyl-N- (2-acryloxyethyl) heptadecafluorooctylsulfonamide and the like.

  7) Vinyl ethers such as ethyl vinyl ether, 2-chloroethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether, phenyl vinyl ether and the like.

  8) Vinyl esters: For example, vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl benzoate and the like.

  9) Styrenes: For example, styrene, methyl styrene, chloromethyl styrene and the like.

  10) Vinyl ketones: For example, methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, phenyl vinyl ketone and the like.

  11) Olefins: For example, ethylene, propylene, i-butylene, butadiene, isoprene and the like.

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

  13) Monomers having a cyano group: for example, acrylonitrile, methacrylonitrile, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, o- (or m-, p-) cyanostyrene, and the like.

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

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

  Furthermore, an unsaturated bond-containing vinyl copolymer obtained by addition-reacting a compound having a (meth) acryloyl group and an epoxy group in the molecule to a carboxyl group present in the molecule of the vinyl copolymer. Is also preferred as a polymer binder. Specific examples of the compound containing both an unsaturated bond and an epoxy group in the molecule include glycidyl acrylate, glycidyl methacrylate, and an epoxy group-containing unsaturated compound described in JP-A No. 11-271969.

  Examples of the present invention are specifically shown below, but the embodiments of the present invention are not limited thereto. Unless otherwise specified, “part” in the examples represents “part by mass” and “%” represents “% by mass”.

<Synthesis of acrylic copolymer 1>
In a three-necked flask under a nitrogen stream, 30 parts of methacrylic acid, 50 parts of methyl methacrylate, 20 parts of ethyl methacrylate, 500 parts of i-propyl alcohol and 3 parts of α, α'-azobis-i-butyronitrile are placed in a nitrogen stream. The reaction was carried out in an oil bath at 80 ° C. for 6 hours. Then, after refluxing for 1 hour at the boiling point of i-propyl alcohol, 3 parts of triethylammonium chloride and 25 parts of glycidyl methacrylate were added and reacted for 3 hours to obtain an acrylic copolymer 1 as a binder. The weight average molecular weight measured using GPC was about 35,000, and the glass transition temperature (Tg) measured using DSC (differential thermal analysis) was about 85 ° C.

<Production of support>
An aluminum plate (material 1050, tempered H16) having a thickness of 0.3 mm was immersed in a 5% aqueous sodium hydroxide solution maintained at 65 ° C., degreased for 1 minute, and then washed with water. This degreased aluminum plate was neutralized by dipping in a 10% aqueous hydrochloric acid solution maintained at 25 ° C. for 1 minute, and then washed with water. Next, the aluminum plate was subjected to electrolytic surface roughening with an alternating current for 60 seconds in a 0.3% nitric acid aqueous solution at 25 ° C. and a current density of 100 A / dm ² , and then kept at 60 ° C. In addition, desmutting treatment was performed for 10 seconds in a 5% aqueous sodium hydroxide solution. The desmutted roughened aluminum plate was anodized in a 15% sulfuric acid solution at 25 ° C., a current density of 10 A / dm ² , and a voltage of 15 V for 1 minute, and further with 1% polyvinylphosphonic acid. Hydrophilic treatment was performed at 75 ° C. to prepare a support.

  At this time, the center line average roughness (Ra) of the surface was 0.65 μm.

<Preparation of lithographic printing plate material>
On the support, a photopolymerizable photosensitive layer coating solution 1 having the following composition was applied with a wire bar so as to be 1.5 g / m ² when dried, and dried at 95 ° C. for 1.5 minutes. A coated sample was obtained.
(Photopolymerizable photosensitive layer coating solution 1)
Bromine compound (described in Table 1) Amount described in Table 1 Photopolymerization initiator (described in Table 1) Amount described in Table 1 Sensitizing dye (described in Table 1) Amount described in Table 1 Ethylene double bond-containing compound M-3 20 parts NK ester 4G (polyethylene glycol dimethacrylate manufactured by Shin-Nakamura Chemical Co., Ltd.)
20 parts Acrylic copolymer 1 40.0 parts N-phenylglycine benzyl ester 4.0 parts Phthalocyanine pigment (MHI454: manufactured by Gokoku Dye Co., Ltd.) 6.0 parts 2-t-butyl-6- (3-t-butyl -2-hydroxy-5-methylbenzyl)-
4-methylphenyl acrylate (Sumilyzer GS: manufactured by Sumitomo 3M) 0.5 parts Fluorosurfactant (F-178K: manufactured by Dainippon Ink & Co.) 0.5 parts Methyl ethyl ketone 80 parts Cyclohexanone 820 parts Application of the above photopolymerized photosensitive layer An oxygen barrier layer coating solution having the following composition is applied on the sample with an applicator so as to be 1.8 g / m ² when dried, and dried at 75 ° C. for 1.5 minutes, and the oxygen barrier layer on the photosensitive layer. Lithographic printing plate materials (Samples 1 to 15) having layers were prepared.
(Oxygen barrier layer coating solution 1)
Polyvinyl alcohol (GL-05: Nippon Synthetic Chemical Co., Ltd.) 89 parts Water-soluble polyamide (P-70: Toray Industries, Inc.) 10 parts Surfactant (Surfinol 465: Nissin Chemical Industry Co., Ltd.) 0.5 parts Water 900 <Preparation and evaluation of planographic printing plates>
Each lithographic printing plate material is exposed at 2400 dpi (dpi is the number of dots per inch or 2.54 cm) using a plate setter (Tiger Cat: modified ECRM) equipped with a laser light source of 408 nm and 30 mV output. Went.

  As the exposure pattern, a 100% image portion and 175 LPI (line per inch) · 50% square dots were used. Next, a preheating part that heat-treats the plate material at 105 degrees for 10 seconds, a pre-washing part that removes the overcoat layer before development, a developing part filled with a developer having the following composition, and a washing part that removes the developer adhering to the plate surface , Development processing is carried out with a CTP automatic developing machine (PHW23-V: manufactured by Technigraph) equipped with a processing unit for gum solution (GW-3: manufactured by Mitsubishi Chemical Co., Ltd.). A lithographic printing plate was obtained.

(Developer composition)
A Potassium silicate 8.0%
New Coal B-13SN (Nippon Emulsifier Co., Ltd.) 3.0%
Caustic potassium pH = 12.3

"sensitivity"
In the 100% image area recorded on the plate surface of the obtained lithographic printing plate, the minimum exposure energy amount at which no film reduction was observed was defined as the recording energy, which was used as an index of sensitivity. The smaller the recording energy, the higher the sensitivity.

<Press life>
A lithographic printing plate produced by exposing and developing an image of 175 lines at 200 μJ / cm ² , coated paper, printing ink (manufactured by Dainippon Ink & Chemicals, Inc .: Soybean oil ink “Naturalis 100”) and dampening water (manufactured by Tokyo Ink Co., Ltd .: H liquid SG-51, density 1.5%) are used for printing, and the number of prints in which highlights are dotted is determined. It was used as an index of printing durability. The greater the number, the better the printing durability.

<Preservation>
Each lithographic printing plate material was forcibly deteriorated at 55 ° C. for 3 days, then exposed and developed under the same conditions as described above, and the difference in recording energy before and after the forced deterioration was determined for the obtained lithographic printing plate. The smaller the difference in recording energy before and after forced deterioration, the better the storage stability.

  The results are also shown in Table 1.

  As shown in Table 1, the lithographic printing plate precursor using the photopolymerizable composition of the present invention for the photopolymerizable photosensitive layer is more sensitive than the lithographic printing plate precursor using the comparative photopolymerizable composition, It was found that the printing durability and storage stability were excellent.

(Example 2)
A sample was prepared in the same manner as in Example 1, except that the bromine compound, photopolymerization initiator and sensitizing dye used in Example 1 were changed to the contents shown in Table 2, and exposure and development were performed. And shelf life were evaluated. The results are shown in Table 2.

  As shown in Table 2, the lithographic printing plate precursor using the photopolymerizable composition of the present invention for the photopolymerizable photosensitive layer has a sensitivity higher than that of the comparative bromine compound, even if the photopolymerization initiator is changed. It was found that the printing durability and storage stability were excellent.

Claims (5)

A photopolymerizable composition comprising an ethylenic double bond-containing compound capable of addition polymerization, a photopolymerization initiator, a sensitizing dye, and a bromine compound having a molecular weight of 500 to 2000 represented by the following general formula (1): object.
Formula (1) R- (O (C = O) -CBr 3) n
[Wherein, R represents an alkyl group, an alkenyl group, an alicyclic hydrocarbon group, an aryl group, or a heterocyclic group. n is an integer of 1-4. However, when n is 2 to 4, the molecular weight of the bromine compound represented by the general formula (1) is 500 or more divided by the total number of tribromoacetyloxy groups in the molecule. ] The photopolymerizable composition according to claim 1, wherein the photopolymerizable composition contains an iron arene compound or a titanocene compound as a photopolymerization initiator. The photopolymerizable composition according to claim 1 or 2, comprising a sensitizing dye represented by the following general formula (2).

[Wherein R ¹ , R ² , R ³ and R ⁴ each represent a hydrogen atom or a substituent, R ^a and R ^b each represent an alkyl group, and X represents a substituent. ] A photosensitive lithographic printing plate precursor comprising a photopolymerizable photosensitive layer containing the photopolymerizable composition according to any one of claims 1 to 3 on a support. A method for producing a lithographic printing plate, comprising producing the photosensitive lithographic printing plate precursor according to claim 4 by scanning and recording imagewise with a laser light source having a wavelength of 350 to 450 nm.