JP2007310057A - Photosensitive composition, photosensitive lithographic printing plate material and method for producing those - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive composition and a photosensitive lithographic printing plate material suitable for exposure with laser light of which the wavelength is within a range of 350-450 nm, having high sensitivity and excellent in storage stability (sensitivity stability in storage), and a method for producing those. <P>SOLUTION: The photosensitive composition comprises (A) a spectral sensitizer, (B) a polymerization initiator, (C) a radical polymerizable compound and (D) a polymer binder, wherein the photosensitive composition comprises a dialkoxyanthracene compound as the spectral sensitizer and at least a hexaarylbisimidazole derivative as the polymerization initiator. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a photosensitive composition, a photosensitive lithographic printing plate material using the same, and a method for producing them. More specifically, the present invention relates to a photosensitive composition and a photosensitive lithographic printing plate material particularly suitable for image formation by scanning exposure such as a laser having a wavelength of 350 to 450 nm, and methods for producing them.

  Photosensitive compositions are widely used in the imaging field and have a long history of research. However, with the development of the industry, market demands such as higher sensitivity, higher resolution, higher strength, and handling are further increasing, and technological innovation advances are still unsettled.

  Such photosensitive compositions include, for example, image formation such as stereolithography, holography, and color hard copy, and the field of manufacturing electronic materials such as photoresists and color filters, and the field of photocurable resin materials such as inks, paints, and adhesives. There is a strong demand for new high-performance materials. One such field is the printing material field.

  In the field of printing materials, in recent years, digitization technology that electronically processes, stores, and outputs image information using a computer has become widespread, and digitized images are used in the preparation of printing plates for offset printing. According to the information, a so-called computer-to-plate (hereinafter referred to as “CTP”) system is developed in which a highly directional laser beam is scanned and recorded directly on a photosensitive lithographic printing plate material. Practical application is progressing.

  On the other hand, in the field of lithographic printing plate materials, with the advancement of image forming technology, photosensitive lithographic printing plate materials exhibiting high sensitivity to relatively inexpensive and low output laser light have been demanded. For example, research on a photosensitive lithographic printing plate corresponding to an output machine using an argon laser, a helium / neon laser, a red LED, or the like has been actively conducted.

  As a typical laser, for example, a semiconductor laser using an InGaN-based material capable of continuous oscillation in a 350 to 450 nm region has 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 the 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 light-sensitive material having a short photosensitive area capable of working under a brighter safe light can be used, which is a preferable embodiment.

  In the field of printing that requires a relatively high printing durability, for example, polymerization containing a polymerizable compound such as a printing plate material described in JP-A-1-105238 and JP-A-2-127404. It is known to use a negative photosensitive lithographic printing plate material having a photosensitive layer.

  As a high-power and small-sized blue-violet laser with a wavelength of 390 to 430 nm becomes readily available, the development of a photosensitive lithographic printing plate suitable for the laser wavelength in this wavelength region will increase the bright room. (See Patent Documents 1, 2, and 3).

  Also known is a printing plate material having improved light-safety under yellow light, for example, a bilayer-containing printing plate material as described in JP-A No. 2001-194482, and has high sensitivity, low As a sublimable photopolymerizable composition, for example, a photopolymerizable composition containing a hexaarylbiimidazole compound containing an aryl group having a substituent such as an alkyl group as described in JP-A-2004-137152 is known. It has been.

  On the other hand, it is known to use distyrylbenzene or the like as a spectral sensitizer used for a polymerization type photosensitive layer corresponding to exposure with a laser beam having an emission wavelength in the range of 350 nm to 450 nm (Patent Document 4). And 5).

However, these photosensitive compositions and printing plate materials have problems in that the sensitivity may be insufficient, and the sensitivity variation with time of the photosensitive lithographic printing plate material may be large.
JP 2000-35673 A JP 2000-98605 A JP 2001-264978 A JP 2003-295426 A JP 2001-348497 A

  The present invention has been made in view of the above problems, and its purpose is suitable for exposure with laser light having a wavelength in the range of 350 to 450 nm, high sensitivity, and storage stability (sensitivity stability during storage). It is an object to provide a photosensitive composition and a photosensitive lithographic printing plate material that are excellent in properties. Moreover, it is in providing those manufacturing methods.

  The above-mentioned problem according to the present invention is solved by the following means.

  1. A photosensitive composition comprising at least (A) a spectral sensitizer, (B) a polymerization initiator, (C) a radical polymerizable compound, and (D) a polymer binder, the spectral sensitizer As a photosensitive composition, at least a compound having a structure represented by the following general formula (1) is contained, and at least a hexaarylbisimidazole derivative is contained as the polymerization initiator.

[Wherein, R ^{1 to} R ⁸ each independently represents a hydrogen atom, a C1 to C12 alkyl group, a fluorine atom, a chlorine atom, a bromine atom, a cyano group, a phenyl group, a cyclohexyl group, a hydroxyl group, a benzyl group, or cyclohexylmethyl. Group, 1-naphthyl group, 2-naphthyl group, 2-hydroxyethyl group, 3-hydroxypropyl group, 4-hydroxybutyl group, —O—R ¹¹ , —CO—R ¹¹ or —S—R ¹¹ (R ¹¹ Is a C1-C8 alkyl group, phenyl group, benzyl group, cyclohexyl group, cyclohexylmethyl group, 1-naphthyl group, 2-naphthyl group, 2-hydroxyethyl group, 3-hydroxypropyl group, or 4-hydroxybutyl group Any one of these). R ⁹ and R ¹⁰ are each independently a C1-C20 alkyl group (which may be branched, may have a substituent, or may be cyclic), an aralkyl group, or an acyl group. ]
2. A method for producing a photosensitive composition comprising at least (A) a spectral sensitizer, (B) a polymerization initiator, (C) a radically polymerizable compound, and (D) a polymer binder, A method for producing a photosensitive composition, comprising producing the photosensitive composition described in 1.

  3. Photosensitive lithographic printing having a photosensitive layer containing at least (A) a spectral sensitizer, (B) a polymerization initiator, (C) a radical polymerizable compound, and (D) a polymer binder on a support. A photosensitive lithographic printing plate material, wherein the photosensitive layer contains at least the photosensitive composition described in 1 above.

  4). Photosensitive lithographic printing having a photosensitive layer containing at least (A) a spectral sensitizer, (B) a polymerization initiator, (C) a radical polymerizable compound, and (D) a polymer binder on a support. A method for producing a photosensitive lithographic printing plate material, which comprises producing the photosensitive lithographic printing plate material described in 3 above.

  With the above configuration of the present invention, a photosensitive composition and a photosensitive lithographic plate that are suitable for exposure with a laser beam having a wavelength in the range of 350 to 450 nm, have high sensitivity, and have excellent storage stability (sensitivity stability during storage). It is possible to provide printing plate materials and methods for their production.

  The photosensitive composition of the present invention comprises at least (A) a spectral sensitizer, (B) a polymerization initiator, (C) a radical polymerizable compound, and (D) a polymer binder. Wherein the spectral sensitizer contains at least a compound having a structure represented by the general formula (1), and the polymerization initiator contains at least a hexaarylbisimidazole derivative. To do.

  Hereinafter, the present invention and its components will be described in detail.

((A) Spectral sensitizer)
The photosensitive composition of the present invention and the photosensitive layer of the photosensitive lithographic printing plate material contain a compound represented by the above general formula (1) as a spectral sensitizer.

In the general formula (1), R ^{1 to} R ⁸ are each independently a hydrogen atom, a C1 to C12 alkyl group, a fluorine atom, a chlorine atom, a bromine atom, a cyano group, a phenyl group, a cyclohexyl group, a hydroxyl group, and a benzyl group. group, cyclohexylmethyl group, 1-naphthyl, 2-naphthyl, 2-hydroxyethyl group, 3-hydroxypropyl group, 4-hydroxybutyl ^{group, -O-R 11, -CO-} R 11 or -S-R ¹¹ (R ¹¹ is an alkyl group of C1 to C8, phenyl group, benzyl group, cyclohexyl group, cyclohexylmethyl group, 1-naphthyl group, 2-naphthyl group, 2-hydroxyethyl group, 3-hydroxypropyl group, or 4 -Any of hydroxybutyl groups). R ⁹ and R ¹⁰ are each independently a C1-C20 alkyl group (which may be branched, may have a substituent, or may be cyclic), an aralkyl group, or an acyl group.

In the above formula (1), the alkyl group of C1~C12 in R ¹ to R ^8, for example a methyl group, an ethyl group, n- propyl group, an isopropyl group, n- butyl group, isobutyl group, tert- butyl group, n-pentyl group, isopentyl group, n-hexyl group, isohexyl group, n-heptyl group, isoheptyl group, n-octyl group, isooctyl group, 2-ethyl-hexyl group, n-nonyl group, isononyl group, n-decyl Group, isodecyl group, n-dodecyl group, isododecyl group and the like.

As —O—R ¹¹ , for example, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, tert-butoxy group, n-pentoxy group, isopentoxy group, n- Hexoxy group, isohexoxy group, n-heptoxy group, isoheptoxy group, n-octoxy group, isooctoxy group, 2-ethylhexoxy group, phenoxy group, phenylmethyloxy group, cyclohexoxy group, cyclohexylmethyloxy group, 1-naphthoxy group, 2 -A naphthoxy group, 2-hydroxyethoxy group, 3-hydroxypropoxy group, 4-hydroxybutoxy group, etc. are mentioned.

Examples of —CO—R ¹¹ include a methylcarbonyl group, an ethylcarbonyl group, an n-propylcarbonyl group, an isopropylcarbonyl group, an n-butylcarbonyl group, an isobutylcarbonyl group, a tert-butylcarbonyl group, an n-pentylcarbonyl group, Isopentylcarbonyl group, n-hexylcarbonyl group, isohexylcarbonyl group, n-heptylcarbonyl group, isoheptylcarbonyl group, n-octylcarbonyl group, isooctylcarbonyl group, 2-ethylhexylcarbonyl group, phenylcarbonyl group, phenylmethyl Carbonyl group, cyclohexylcarbonyl group, cyclohexylmethylcarbonyl group, 1-naphthylcarbonyl group, 2-naphthylcarbonyl group, 2-hydroxyethylcarbonyl group, 3-hydroxypropylcarbohydrate Group, such as 4-hydroxybutyl group and the like.

Examples of the substituent —S—R ¹¹ include a methylthio group, an ethylthio group, an n-propylthio group, an isopropylthio group, an n-butylthio group, an isobutylthio group, a tert-butylthio group, an n-pentylthio group, and an isopentylthio group. N-hexylthio group, isohexylthio group, n-heptylthio group, isoheptylthio group, n-octylthio group, isooctylthio group, 2-ethylhexylthio group, phenylthio group, phenylmethylthio group, cyclohexylthio group, cyclohexylmethylthio group, Examples include 1-naphthylthio group, 2-naphthylthio group, 2-hydroxyethylthio group, 3-hydroxypropylthio group, 4-hydroxybutylthio group, and the like.

Specific examples of the C1-C20 alkyl group for R ⁹ and R ¹⁰ (which may be branched, may have a substituent, or may be cyclic) include, for example, a methyl group and an ethyl group N-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group, isopentyl group, n-hexyl group, isohexyl group, n-heptyl group, isoheptyl group, n-octyl group , Isooctyl group, 2-ethyl-hexyl group, n-nonyl group, isononyl group, n-decyl group, isodecyl group, n-dodecyl group, isododecyl group, nonadecyl group, cyclohexyl group and the like.

  The content of the compound represented by the general formula (1) contained in the photosensitive composition or photosensitive layer according to the present invention can be adjusted to an appropriate amount depending on the purpose. 0.1-10 mass% is preferable with respect to a photosensitive layer, and 0.5-8 mass% is especially preferable.

  Although the specific example of a compound represented by General formula (1) below is given, it is not limited to these.

  As spectral sensitizers, in addition to the above compounds, for example, JP 2000-98605, JP 2000-147663, JP 2000-206690, JP 2000-258910, JP 2000-309724, The spectral sensitizers described in JP-A Nos. 2001-042524, 2002-202598, and 2000-221790 may also be included.

((B) polymerization initiator)
The polymerization initiator according to the present invention is capable of initiating polymerization of a polymerizable ethylenic double bond-containing compound or the like by image exposure, and the photosensitive composition according to the present invention is at least as a polymerization initiator. It contains a hexaarylbisimidazole derivative.

  The process for the preparation of such hexaarylbisimidazoles (HABI, a triaryl-imidazole dimer) is described in DE 1470154 and their use in photopolymerizable compositions is described in EP 24629. No., EP 107792, U.S. Pat. No. 4,410,621, EP 215453 and DE 3211312.

  Preferred hexaarylbisimidazole derivatives are, for example, 2,4,5,2 ′, 4 ′, 5′-hexaphenylbisimidazole, 2,2′-bis (2-chlorophenyl) -4,5,4 ′, 5. '-Tetraphenylbisimidazole, 2,2'-bis (2-bromophenyl) -4,5,4', 5'-tetraphenylbisimidazole, 2,2'-bis (2,4-dichlorophenyl) -4 , 5,4 ', 5'-tetraphenylbisimidazole, 2,2'-bis (2-chlorophenyl) -4,5,4', 5'-tetrakis (3-methoxyphenyl) bisimidazole, 2,2 ' -Bis (2-chlorophenyl) -4,5,4 ', 5'-tetrakis (3,4,5-trimethoxyphenyl) -bisimidazole, 2,5,2', 5'-tetrakis (2-c Rophenyl) -4,4'-bis (3,4-dimethoxyphenyl) bisimidazole, 2,2'-bis (2,6-dichlorophenyl) -4,5,4 ', 5'-tetraphenylbisimidazole, 2 , 2'-bis (2-nitrophenyl) -4,5,4 ', 5'-tetraphenylbisimidazole, 2,2'-di-o-tolyl-4,5,4', 5'-tetraphenyl Bisimidazole, 2,2'-bis (2-ethoxyphenyl) -4,5,4 ', 5'-tetraphenylbisimidazole and 2,2'-bis (2,6-difluorophenyl) -4,5 4 ', 5'-tetraphenylbisimidazole.

  Examples of the polymerization initiator according to the present invention include, in addition to hexaarylbisimidazole derivatives, biimidazoles other than titanocene compounds, monoalkyltriarylborate compounds, iron arene complex compounds, polyhalogen compounds, and hexaarylbisimidazole derivatives. A compound or the like can be used in combination.

  Examples of titanocene compounds include compounds described in JP-A-63-41483 and JP-A-2-291. More preferred specific examples include bis (cyclopentadienyl) -Ti-di-chloride, bis (Cyclopentadienyl) -Ti-bis-phenyl, bis (cyclopentadienyl) -Ti-bis-2,3,4,5,6-pentafluorophenyl, bis (cyclopentadienyl) -Ti-bis -2,3,5,6-tetrafluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,4,6-trifluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,6 -Difluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,4-difluorophenyl, bis (methylcyclopentadienyl) -Ti-bis- , 3,4,5,6-pentafluorophenyl, bis (methylcyclopentadienyl) -Ti-bis-2,3,5,6-tetrafluorophenyl, bis (methylcyclopentadienyl) -Ti-bis -2,6-difluorophenyl (IRUGACURE 727L: manufactured by Ciba Specialty Chemicals), bis (cyclopentadienyl) -bis (2,6-difluoro-3- (py-1-yl) phenyl) titanium (IRUGACURE 784: Ciba Specialty Chemicals), bis (cyclopentadienyl) -bis (2,4,6-trifluoro-3- (pyridin-1-yl) phenyl) titanium bis (cyclopentadienyl) -bis (2, 4,6-trifluoro-3- (2-5-dimethylpy-1-yl) phenyl) titanium and the like It is below.

  Examples of the monoalkyl triaryl borate compound include compounds described in JP-A-62-150242 and JP-A-62-143044, and more preferable specific examples include tetra-n-butylammonium / n-butyrate. Linaphthalen-1-yl-borate, tetra-n-butylammonium / n-butyl-triphenyl-borate, tetra-n-butylammonium / n-butyl-tri- (4-tert-butylphenyl) -borate, tetra-n -Butylammonium n-hexyl rootri- (3-chloro-4-methylphenyl) -borate, tetra-n-butylammonium n-hexyl rootri- (3-fluorophenyl) -borate and the like.

  Examples of the iron arene complex compound include compounds described in JP-A-59-219307. More preferred specific examples include η-benzene- (η-cyclopentadienyl) iron hexafluorophosphate, η-cumene. -(Η-cyclopentadienyl) iron hexafluorophosphate, η-fluorene- (η-cyclopentadienyl) iron hexafluorophosphate, η-naphthalene- (η-cyclopentadienyl) iron hexafluorophosphate, η- And xylene- (η-cyclopentadienyl) iron hexafluorophosphate, η-benzene- (η-cyclopentadienyl) iron tetrafluoroborate, and the like.

  As the polyhalogen compound, a compound having a trihalogenmethyl group, a dihalogenmethyl group or a dihalomethylene group is preferably used, and in particular, the halogen compound represented by the following general formula (PH1) and the above group is substituted with an oxadiazole ring. A compound is preferably used.

  Among these, a halogen compound represented by the following general formula (PH2) is particularly preferably used.

Formula (PH1) R ¹ —CY ₂ — (C═O) —R ²
In the formula, R ¹ represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, an iminosulfonyl group, or a cyano group. R ² represents a monovalent substituent. R ¹ and R ² may be bonded to form a ring. Y represents a halogen atom.

Formula (PH2) CY ₃ — (C═O) —X—R ³
In the formula, R ³ represents a monovalent substituent. X represents —O— or —NR ⁴ —. R ⁴ represents a hydrogen atom or an alkyl group. R ³ and R ⁴ may be bonded to form a ring. Y represents a halogen atom. Among these, those having a polyhalogenacetylamide group are particularly preferably used.

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

  In addition, any polymerization initiator can be used in combination. For example, J. et al. Carbonyl compounds, organic sulfur compounds, persulfides, redox compounds, azo, diazo compounds, halogen compounds, and photoreductive dyes as described in Chapter 5 of “Light Sensitive Systems” by J. Kosar Etc. More specific compounds are disclosed in British Patent 1,459,563.

  That is, as the polymerization initiator that can be used in combination, the following can be used.

  Benzoin derivatives such as benzoin methyl ether, benzoin-i-propyl ether, α, α-dimethoxy-α-phenylacetophenone; benzophenone, 2,4-dichlorobenzophenone, methyl o-benzoylbenzoate, 4,4′-bis (dimethyl) Benzophenone derivatives such as amino) benzophenone; thioxanthone derivatives such as 2-chlorothioxanthone and 2-i-propylthioxanthone; anthraquinone derivatives such as 2-chloroanthraquinone and 2-methylanthraquinone; N-methylacridone, N-butylacridone and the like In addition to α, α-diethoxyacetophenone, benzyl, fluorenone, xanthone and uranyl compounds, JP-B-59-1281, 61-9621 and JP-A-60-60104 Triazine derivatives; organic peroxides described in JP-A-59-1504 and JP-A-61-243807; JP-B-43-23684, JP-A-44-6413, JP-A-44-6413, JP-A-47-1604, and US patents Diazonium compounds described in US Pat. No. 3,567,453; organic azide compounds described in US Pat. Nos. 2,848,328 and 2,852,379 and 2,940,853; O-quinonediazides described in JP-A Nos. 13109, 38-18015 and 45-9610; JP-B-55-39162, JP-A-59-14023 and “Macromolecules”, Vol. 10, 1307 Various onium compounds described on page 1977; azo compounds described in JP-A-59-142205 Compound: JP-A-1-54440, European Patents 109,851, 126,712 and “Journal of Imaging Science (J. Imag. Sci.)”, Vol. 30, 174 (1986) (Oxo) sulfonium organoboron complexes described in Japanese Patent Application Nos. 4-56831 and 4-89535; "Coordination Chemistry Review", 84, 85-277 (1988) ) And transition metal complexes containing a transition metal such as ruthenium described in JP-A-2-182701; 2,4,5-triarylimidazole dimer described in JP-A-3-209477; carbon tetrabromide, JP Organic halogen compounds described in JP-A-59-107344, etc.

  The amount of the hexabisimidazole derivative according to the present invention and other polymerization initiator added to the photosensitive layer is not particularly limited, but is preferably 0.1% by mass to 20% by mass with respect to the compound capable of radical polymerization. % Is preferable, and 0.5% by mass to 15% by mass is particularly preferable.

((C) Compound capable of radical polymerization)
The “radically polymerizable compound” according to the present invention is a compound that can be polymerized by using a product (radical species) of a reaction of a polymerization initiator by image exposure. As the polymerizable compound according to the present invention, a wide range of compounds capable of initiating a polymerization reaction triggered by a reaction with a radical species generated from the polymerization initiator according to the present invention can be used.

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

In the present invention, reaction products of the following compounds (C1) to (C3) are particularly preferably used as the polymerizable ethylenic double bond-containing compound.
(C1) a compound containing at least one ethylenic double bond and one hydroxyl group in the molecule (C2) a diisocyanate compound (C3) a diol compound having a tertiary amine structure in the molecule, or an intramolecular Compound having a secondary amine structure and one hydroxyl group each as C1 includes, for example, 2-hydroxyethyl methacrylate, 4-hydroxybutyl acrylate, 2-hydroxypropyl methacrylate.

Examples of C2 include 1,3-bis (1-isocyanato-1-methylethyl) benzene (2 mol), 1,3-diisocyanatobenzene, 1,3-diisocyanate-4-methylbenzene, 1 , 3-Di (isocyanatomethyl) benzene,
Examples of C3 include Nn-butyldiethanolamine, N-methyldiethanolamine, 1,4-di (2-dihydroxyethyl), N-ethyldiethanolamine, and the like.

  As the reaction product, a compound represented by the following general formula (2) is particularly preferably used.

In general formula (2), R ¹ represents a hydrogen atom or a methyl group. X ¹ represents a divalent aliphatic group. X ² represents a divalent hydrocarbon group having an aromatic ring. X ³ represents a divalent substituent having a tertiary amine structure.

X ¹ is, for example, —CH ₂ CH ₂ —, —CH ₂ CH (CH ₃ ) —, —CH (CH ₃ ) CH ₂ —, —CH ₂ CH ₂ CH ₂ —, —CH ₂ CH ₂ CH _2. CH ₂ -, but are mentioned _{-CH 2 CH 2 -, - CH} 2 CH (CH 3) -, - CH (CH 3) CH 2 - is preferred.

Examples of X ² include the following structures X2-1 to X2-10, and X2-3, X2-4, X2-7, X2-9, and X2-10 are preferable.

Examples of X ³ include the structures of X3-1 to X3-10, and X3-1, X3-2, X3-5, and X3-9 are preferable.

  Examples of the compound represented by the general formula (2) include the following compounds.

  In the present invention, the radical polymerizable compound includes a general radical polymerizable monomer, a polyfunctional monomer having a plurality of addition-polymerizable ethylenic double bonds in a molecule generally used for UV curable resins. And polyfunctional oligomers can be used in combination.

  These compounds are not limited, but preferred examples include 2-ethylhexyl acrylate, 2-hydroxypropyl acrylate, glycerol acrylate, tetrahydrofurfuryl acrylate, phenoxyethyl acrylate, nonylphenoxyethyl acrylate, tetrahydrofurfuryloxyethyl acrylate, Monofunctional acrylic acid esters such as tetrahydrofurfuryloxyhexanolide acrylate, acrylate of ε-caprolactone adduct of 1,3-dioxane alcohol, 1,3-dioxolane acrylate, or these acrylates as methacrylate, itaconate, crotonate, Methacrylic acid instead of maleate, itaconic acid, crotonic acid, maleic acid ester such as ethylene glycol Chryrate, triethylene glycol diacrylate, pentaerythritol diacrylate, hydroquinone diacrylate, resorcinol diacrylate, hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, diacrylate of neopentyl glycol hydroxypivalate, neo Diacrylate of pentyl glycol adipate, diacrylate of ε-caprolactone adduct of neopentyl glycol hydroxypivalate, 2- (2-hydroxy-1,1-dimethylethyl) -5-hydroxymethyl-5-ethyl-1,3 -Ε-caprolactone of dioxane diacrylate, tricyclodecane dimethylol acrylate, tricyclodecane dimethylol acrylate Additives, bifunctional acrylates such as diglycidyl ether diacrylate of 1,6-hexanediol, or methacrylic acid, itaconic acid, crotonic acid, maleic acid in which these acrylates are replaced with methacrylate, itaconate, crotonate, maleate Acid esters such as trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, trimethylolethane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, Ε-caprolactone adduct of dipentaerythritol hexaacrylate, pyrogallol tria Relate, polyfunctional acrylic acid ester acid such as propionic acid / dipentaerythritol triacrylate, propionic acid / dipentaerythritol tetraacrylate, hydroxypivalylaldehyde-modified dimethylolpropane triacrylate, or these acrylates with methacrylate, itaconate, crotonate, Examples thereof include methacrylic acid, itaconic acid, crotonic acid, and maleic acid ester instead of maleate.

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

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

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

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

  In addition, JP-A-58-212994, 61-6649, 62-46688, 62-48589, 62-173295, 62-187092, 63- 67189, JP-A-1-244891, and the like. Further, “11290 Chemical Products”, Chemical Industry Daily, p. 286-p. 294, “UV / EB Curing Handbook (raw material)”, Kobunshi Publishing Co., p. The compounds described in 11 to 65 can also be suitably used in the present invention. Of these, compounds having two or more acrylic groups or methacryl groups in the molecule are preferred in the present invention, and those having a molecular weight of 10,000 or less, more preferably 5,000 or less are preferred.

  In addition, acrylates or alkyl acrylates described in JP-A-1-105238 and JP-A-2-127404 can be used.

  The content of the polymerizable ethylenic double bond-containing compound according to the present invention in the photosensitive layer is preferably 0.5% by mass to 15.0% by mass, particularly 1.0-8. 0% by mass is preferred.

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

  A vinyl copolymer obtained by copolymerization of acrylic monomers is preferred. Furthermore, the copolymer composition of the polymer binder is preferably a copolymer of (a) a carboxyl group-containing monomer, (b) a methacrylic acid alkyl ester, or an acrylic acid alkyl ester.

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

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

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

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

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

  3) A monomer having an aminosulfonyl group, such as m- (or p-) aminosulfonylphenyl methacrylate, m- (or p-) aminosulfonylphenyl acrylate, N- (p-aminosulfonylphenyl) methacrylamide, N- (p -Aminosulfonylphenyl) acrylamide and the like.

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

  5) Acrylamide or methacrylamides such as acrylamide, methacrylamide, N-ethylacrylamide, N-hexylacrylamide, N-cyclohexylacrylamide, N-phenylacrylamide, N- (4-nitrophenyl) acrylamide, N-ethyl-N- Phenylacrylamide, N- (4-hydroxyphenyl) acrylamide, N- (4-hydroxyphenyl) methacrylamide and the like.

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

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

  8) Vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl benzoate and the like.

  9) Styrenes such as styrene, methyl styrene, chloromethyl styrene and the like.

  10) Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, and phenyl vinyl ketone.

  11) Olefins such as ethylene, propylene, i-butylene, butadiene, isoprene and the like.

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

  13) Monomers having a cyano group, such as acrylonitrile, methacrylonitrile, 2-pentenenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, o- (or m-, p-) cyanostyrene.

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

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

  Furthermore, the polymer binder is preferably a vinyl polymer having a carboxyl group and a polymerizable double bond in the side chain. For example, an unsaturated bond-containing vinyl copolymer obtained by addition-reacting a compound having a (meth) acryloyl group and an epoxy group in the molecule to a carboxyl group present in the molecule of the vinyl copolymer. Is also preferred as a polymer binder.

  Specific examples of the compound containing both an unsaturated bond and an epoxy group in the molecule include glycidyl acrylate, glycidyl methacrylate, and an epoxy group-containing unsaturated compound described in JP-A No. 11-271969. In addition, an unsaturated bond-containing vinyl copolymer obtained by adding a compound having a (meth) acryloyl group and an isocyanate group in the molecule to a hydroxyl group present in the molecule of the vinyl polymer is also high. Preferred as a molecular binder. Compounds having both an unsaturated bond and an isocyanate group in the molecule include vinyl isocyanate, (meth) acrylic isocyanate, 2- (meth) acryloyloxyethyl isocyanate, m- or p-isopropenyl-α, α'-dimethylbenzyl. Isocyanates are preferred, and (meth) acrylic isocyanate, 2- (meth) acryloyloxyethyl isocyanate and the like can be mentioned.

  The vinyl polymer having a carboxyl group and a polymerizable double bond in the side chain is preferably 50 to 100% by mass, and more preferably 100% by mass in the total polymer binder.

  The content of the polymer binder in the photosensitive layer is preferably in the range of 10 to 90% by mass, more preferably in the range of 15 to 70% by mass, and the use in the range of 20 to 50% by mass from the viewpoint of sensitivity. Particularly preferred.

(Various additives)
In the photosensitive layer according to the present invention, in addition to the above-described components, in order to prevent unnecessary polymerization of the ethylenic double bond monomer that can be polymerized during the production or storage of the photosensitive lithographic printing plate material, It is desirable to add a polymerization inhibitor.

  Suitable polymerization inhibitors include hydroquinone, p-methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4'-thiobis (3-methyl-6-t-butylphenol) 2,2'-methylenebis (4-methyl-6-t-butylphenol), N-nitrosophenylhydroxylamine cerium salt, 2-t-butyl-6- (3-t-butyl-2-hydroxy-5) -Methylbenzyl) -4-methylphenyl acrylate and the like.

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

  Moreover, a coloring agent can also be used and a conventionally well-known thing can be used conveniently as a coloring agent including a commercially available thing. Examples include those described in the revised new edition “Pigment Handbook”, edited by Japan Pigment Technology Association (Seikodo Shinkosha), Color Index Handbook, and the like.

  Examples of the pigment include black pigment, yellow pigment, red pigment, brown pigment, purple pigment, blue pigment, green pigment, fluorescent pigment, and metal powder pigment. Specifically, inorganic pigments (titanium dioxide, carbon black, graphite, zinc oxide, Prussian blue, cadmium sulfide, iron oxide, and lead, zinc, barium and calcium chromates) and organic pigments (azo-based, thioindigo) , Anthraquinone, anthanthrone, and triphendioxazine pigments, vat dye pigments, phthalocyanine pigments and derivatives thereof, quinacridone pigments, and the like.

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

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

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

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

  Examples of the solvent used in preparing the photosensitive layer coating solution for the photosensitive layer according to the present invention include, for example, alcohol: polyhydric alcohol derivatives, sec-butanol, isobutanol, n-hexanol, benzyl alcohol, Diethylene glycol, triethylene glycol, tetraethylene glycol, 1,5-pentanediol, ethers: propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, ketones, aldehydes: diacetone alcohol, cyclohexanone Preferred examples include methylcyclohexanone and esters: ethyl lactate, butyl lactate, diethyl oxalate, methyl benzoate and the like.

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

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

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

  This protective layer (oxygen barrier layer) is preferably highly soluble in a developer (described below, generally an aqueous alkali solution) described below, and specific examples include polyvinyl alcohol and polyvinyl pyrrolidone. Polyvinyl alcohol has an effect of suppressing permeation of oxygen, and polyvinyl pyrrolidone has an effect of ensuring adhesion with an adjacent photosensitive layer.

  In addition to the above two polymers, polysaccharides, polyethylene glycol, gelatin, glue, casein, hydroxyethyl cellulose, carboxymethyl cellulose, methyl cellulose, hydroxyethyl starch, gum arabic, sucrose octaacetate, ammonium alginate, sodium alginate as required Water-soluble polymers such as polyvinylamine, polyethylene oxide, polystyrene sulfonic acid, polyacrylic acid, and water-soluble polyamide can also be used in combination.

  When a protective layer is provided on the photosensitive lithographic printing plate of the present invention, the peeling force between the photosensitive layer and the protective layer is preferably 35 mN / mm or more, more preferably 50 mN / mm or more, and even more preferably 75 mN / mm or more. is there. Preferred examples of the protective layer composition include those described in Japanese Patent Application No. 8-161645.

  In the present invention, the peeling force is obtained by applying an adhesive tape having a predetermined width on the protective layer and having a sufficiently large adhesive force, and peeling it together with the protective layer at an angle of 90 degrees with respect to the plane of the photosensitive lithographic printing plate material. It can be determined by measuring the force.

  The protective layer can further contain a surfactant, a matting agent and the like as required. The protective layer composition is dissolved in a suitable solvent, applied onto the photosensitive layer and dried to form a protective layer. The main component of the coating solvent is particularly preferably water or alcohols such as methanol, ethanol, i-propanol.

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

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

  Examples of the support according to the present invention include a metal plate such as aluminum, stainless steel, chromium and nickel, or a laminate obtained by laminating or vapor-depositing the above metal thin film on a plastic film such as a polyester film, a polyethylene film and a polypropylene film. .

  Moreover, although what hydrophilized the surface, such as a polyester film, a vinyl chloride film, a nylon film, etc. can be used, an aluminum support body is used preferably.

  In the case of an aluminum support, pure aluminum or an aluminum alloy is used.

  Various aluminum alloys can be used as the support, and for example, alloys of metals such as silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth, nickel, titanium, sodium, iron, and aluminum are used. . Further, the aluminum support having a roughened surface is used for water retention.

  In the case of using an aluminum support, it is preferable to perform a degreasing treatment in order to remove the rolling oil on the surface prior to roughening (graining treatment). As the degreasing treatment, a degreasing treatment using a solvent such as trichlene or thinner, an emulsion degreasing treatment using an emulsion such as kesilon or triethanol, or the like is used. In addition, an alkaline aqueous solution such as caustic soda can be used for the degreasing treatment. When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, dirt and oxide film that cannot be removed only by the degreasing treatment can be removed. When an alkaline aqueous solution such as caustic soda is used for the degreasing treatment, smut is generated on the surface of the support. In this case, the substrate is immersed in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid, or a mixed acid thereof and desmutted. It is preferable to perform the treatment. Examples of the roughening method include a mechanical method and a method of etching by electrolysis.

  The mechanical roughening method used is not particularly limited, but a brush polishing method and a honing polishing method are preferable.

  The electrochemical surface roughening method is not particularly limited, but a method of electrochemical surface roughening in an acidic electrolyte is preferable.

  After the surface is roughened by the electrochemical surface roughening method, it is preferably immersed in an acid or alkali aqueous solution in order to remove aluminum scraps on the surface. Examples of the acid include sulfuric acid, persulfuric acid, hydrofluoric acid, phosphoric acid, nitric acid, hydrochloric acid, and the like. Examples of the base include sodium hydroxide and potassium hydroxide. Among these, it is preferable to use an alkaline aqueous solution.

The dissolution amount of aluminum in the support surface, 0.5 to 5 g / m ² is preferred. In addition, it is preferable that after the immersion treatment with an alkaline aqueous solution, neutralization treatment is performed by immersion in an acid such as phosphoric acid, nitric acid, sulfuric acid, chromic acid or a mixed acid thereof.

  The mechanical surface roughening method and the electrochemical surface roughening method may each be used alone for roughing, or the mechanical surface roughening method followed by the electrochemical surface roughening method. You may roughen.

  Following the roughening treatment, an anodic oxidation treatment can be performed. There is no restriction | limiting in particular in the method of the anodizing process which can be used in this invention, A well-known method can be used. By performing the anodizing treatment, an oxide film is formed on the support.

  The anodized support may be sealed as necessary. These sealing treatments can be performed using known methods such as hot water treatment, boiling water treatment, water vapor treatment, sodium silicate treatment, dichromate aqueous solution treatment, nitrite treatment, and ammonium acetate treatment.

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

(Application)
The above photosensitive layer coating solution can be coated on a support by a conventionally known method and dried to prepare a photosensitive lithographic printing plate material.

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

  The drying temperature of the photosensitive layer is preferably in the range of 60 to 160 ° C., more preferably 80 to 140 ° C., and particularly preferably 90 to 120 ° C.

(Image exposure)
As a light source for recording an image on the photosensitive lithographic printing plate material of the present invention, it is preferable to use a laser beam having an emission wavelength of 370 to 440 nm.

As a light source for exposing the photosensitive lithographic printing plate of the present invention, for example, a He—Cd laser (441 nm), a combination of Cr: LiSAF and SHG crystal (430 nm) as a solid laser, KNbO ₃ as a semiconductor laser system, a ring A resonator (430 nm), AlGaInN (350 nm to 450 nm), an AlGaInN semiconductor laser (commercially available InGaN semiconductor laser 400 to 410 nm) and the like can be mentioned.

  Laser exposure is suitable for direct writing without using a mask material because light exposure can be performed in the form of a beam according to image data.

  When a laser is used as a light source, it is easy to reduce the exposure area to a very small size, and high-resolution image formation is possible.

  Laser scanning methods include cylindrical outer surface scanning, cylindrical inner surface scanning, and planar scanning. In the cylindrical outer surface scanning, laser exposure is performed while rotating a drum around which the recording material is wound, and the rotation of the drum is the main scanning and the movement of the laser light is the sub scanning. In cylindrical inner surface scanning, a recording material is fixed to the inner surface of the drum, a laser beam is irradiated from the inside, and a main scanning is performed in the circumferential direction by rotating a part or all of the optical system. Sub scanning is performed in the axial direction by linearly moving all of them in parallel with the drum axis. In plane scanning, a laser beam main scan is performed by combining a polygon mirror, a galvanometer mirror, and an fθ lens, and a sub-scan is performed by moving a recording medium. Cylindrical outer surface scanning and cylindrical inner surface scanning are easier to increase the accuracy of the optical system and are suitable for high-density recording.

In the present invention, image exposure is preferably performed with a plate surface energy (energy on the plate material) of 10 mJ / cm ² or more, and the upper limit is 500 mJ / cm ² . More preferably, it is 10-300 mJ / cm < ² >. For this energy measurement, for example, a laser power meter PDGDO-3W manufactured by OphirOptics can be used.

(Developer)
The exposed portion of the photosensitive layer subjected to image exposure is cured. This is preferably developed with an alkaline developer to remove unexposed portions and form an image.

  As such a developer, a conventionally known alkaline aqueous solution can be used. For example, sodium silicate, potassium, ammonium; dibasic sodium phosphate, potassium, ammonium; sodium bicarbonate, potassium, ammonium; sodium carbonate, potassium, ammonium; sodium bicarbonate, potassium, ammonium An alkali developer using an inorganic alkaline agent such as sodium borate, potassium, ammonium; sodium hydroxide, potassium, ammonium and lithium;

  Also, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, mono-i-propylamine, di-i-propylamine, tri-i-propylamine, butylamine, monoethanolamine, diethanolamine, triethanolamine, Organic alkali agents such as mono-i-propanolamine, di-i-propanolamine, ethyleneimine, ethylenediamine, and pyridine can also be used.

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

  Alkaline developers can also be prepared from developer concentrates such as granules and tablets.

  The developer concentrate may be evaporated to dryness once it is made into a developer, but preferably the materials are mixed by adding a small amount of water without adding water when mixing a plurality of materials. A method of concentrating with is preferable. The developer concentrates are disclosed in JP-A-51-61837, JP-A-2-109042, JP-A-2-109043, JP-A-3-39735, JP-A-5-142786, JP-A-6-266062, and JP-A-7. Granules and tablets can be obtained by a well-known method described in No. 13341 or the like. Further, the developer concentrate may be divided into a plurality of parts having different material types, material mixing ratios, and the like.

  The alkaline developer and its replenisher may further contain preservatives, colorants, thickeners, antifoaming agents, hard water softeners, and the like as necessary.

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

  The automatic processor may have a pretreatment unit that immerses the plate in the pretreatment liquid before the development step. The pretreatment unit is preferably provided with a mechanism for spraying the pretreatment liquid on the plate surface, and preferably provided with a mechanism for controlling the temperature of the pretreatment liquid to an arbitrary temperature of 25 to 55 ° C. Is provided with a mechanism for rubbing the plate surface with a roller-like brush. Water or the like is used as the pretreatment liquid.

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

  These post-processing are generally performed using an automatic developing machine including a developing unit and a post-processing unit. As the post-treatment liquid, a method of spraying from a spray nozzle or a method of immersing and conveying in a treatment tank filled with the treatment liquid is used. A method is also known in which a fixed amount of a small amount of washing water is supplied to the plate surface after development, and the waste liquid is reused as dilution water for the developer stock solution. In such automatic processing, processing can be performed while each replenisher is replenished with each replenisher according to the processing amount, operating time, and the like. In addition, a so-called disposable treatment method in which treatment is performed with a substantially unused post-treatment liquid is also applicable. The lithographic printing plate obtained by such processing is loaded on an offset printing machine and used for printing a large number of sheets.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, the aspect of this invention is not limited to this. In the examples, “parts” represents “parts by mass” unless otherwise specified.

(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 under conditions of 25 ° C. and a current density of 100 A / dm ^{2 in} a 0.3% by mass nitric acid aqueous solution, and then kept at 60 ° C. 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 samples)
On the support, a photosensitive layer coating solution 1 having the following composition was coated with a wire bar so that the dried layer was 1.5 g / m ² , dried at 95 ° C. for 1.5 minutes, and then coated with an oxygen barrier layer. Liquid 1 was applied with a wire bar so as to be 1.5 g / m ² when dried, and dried at 75 ° C. for 1.5 minutes to obtain planographic printing plate materials Examples 1 to 12 and Comparative Examples 1 to 3.

(Photosensitive layer coating solution 1)
50% by mass of a reaction product of Nn-butyldiethanolamine (1 mol), 1,3-bis (1-isocyanato-1-methylethyl) benzene (2 mol), 2-hydroxyethyl methacrylate (2 mol) Dawanol PMA solution 84.0 parts Triethylene glycol dimethacrylate 6.0 parts Copolymer of methacrylic acid and methyl methacrylate in a mass ratio of 25:75 (molecular weight 36000) 35.0 parts Spectral sensitizer according to Table 1. 0 parts 2,2'-bis (2-chlorophenyl) -4,5,4 ', 5'-tetraphenylbiimidazole 3.0 parts 2-mercaptobenzothiazole 0.3 part N-phenylglycine benzyl ester 4.0 Part phthalocyanine pigment (MHI # 454: manufactured by Mikuni Dye Co., Ltd.) 3.5 parts 2-t-butyl-6- (3-t-butyl-2 -Hydroxy-5-methylbenzyl) -4-methylphenyl acrylate (Sumilyzer GS: manufactured by Sumitomo 3M) 0.2 part 2,4,6-tris (dimethylaminomethyl) phenol 1.0 part bis (2,2, 6,6-Tetramethyl-4-piperidyl) sebacate 0.1 part Fluorosurfactant (F-178K; manufactured by Dainippon Ink & Co.) 0.5 part Siloxane surfactant (BYK337; manufactured by BYK Chemie) 0. 9 parts Methyl ethyl ketone 80 parts Propylene glycol methyl ether 820 parts (Oxygen barrier coating liquid 1)
Polyvinyl alcohol (Cell Ball 103: manufactured by Celanese) 85.0 parts Vinylpyrrolidone / vinyl acetate copolymer (Rubitech VA64W: manufactured by BASF) 15.0 parts Surfinol 465 (manufactured by Air Products) 0.2 part Water 900 (Evaluation of planographic printing plate materials)
(sensitivity)
The planographic printing plate material was exposed at 2400 dpi (dpi represents the number of dots per 2.54 cm) using a plate setter (NewsCTP: manufactured by ECRM) equipped with a light source of 405 nm and 60 mW.

  As the exposure pattern, original image data having a 100% image portion, Times New Roughman font, 3 to 10 point size, and uppercase and lowercase letters without alphabetic characters were used.

  Next, a preheating section set at 105 ° C., a pre-water washing section for removing the oxygen blocking layer, a developing solution having the following composition are filled, and the developing section whose temperature is adjusted to 30 ° C. and the developing solution adhering to the plate surface are removed. Developed with a CTP automatic developing machine (Raptor Polymer: GLUNZ & JENSEN) equipped with a processing unit for gum washing (GW-3: manufactured by Mitsubishi Chemical Co., Ltd.) And a lithographic printing plate was obtained.

(Developer composition (aqueous solution containing the following additives))
A Potassium silicate 8.0 parts New Coal B-13SN: Nippon Emulsifier Co., Ltd. 3.0 parts Water 89.0 parts Caustic potash pH = 12.3 added amount 100 recorded on the plate surface of the lithographic printing plate In the% image area, the minimum amount of exposure energy at which no film reduction was observed was taken as the recording energy and used as an index of sensitivity. The smaller the recording energy, the higher the sensitivity.

(Sensitivity fluctuation during storage)
The lithographic printing plate material was stored in a constant temperature bath at 55 ° C. for 3 days, then the sensitivity was measured by the same method as described above, and the percentage of the sensitivity before storage was calculated and used as an index of storage stability. The closer to 100%, the smaller the fluctuation and the better the storage stability.

  The results are shown in Table 1. It can be seen from Table 1 that the photosensitive lithographic printing plate material of the present invention has high sensitivity and is excellent in storability with little variation in sensitivity during storage.

Claims (4)

A photosensitive composition comprising at least (A) a spectral sensitizer, (B) a polymerization initiator, (C) a radical polymerizable compound, and (D) a polymer binder, the spectral sensitizer As a photosensitive composition, at least a compound having a structure represented by the following general formula (1) is contained, and at least a hexaarylbisimidazole derivative is contained as the polymerization initiator.

[Wherein, R ^{1 to} R ⁸ each independently represents a hydrogen atom, a C1 to C12 alkyl group, a fluorine atom, a chlorine atom, a bromine atom, a cyano group, a phenyl group, a cyclohexyl group, a hydroxyl group, a benzyl group, or cyclohexylmethyl. Group, 1-naphthyl group, 2-naphthyl group, 2-hydroxyethyl group, 3-hydroxypropyl group, 4-hydroxybutyl group, —O—R ¹¹ , —CO—R ¹¹ or —S—R ¹¹ (R ¹¹ Is a C1-C8 alkyl group, phenyl group, benzyl group, cyclohexyl group, cyclohexylmethyl group, 1-naphthyl group, 2-naphthyl group, 2-hydroxyethyl group, 3-hydroxypropyl group, or 4-hydroxybutyl group Any one of these). R ⁹ and R ¹⁰ are each independently a C1-C20 alkyl group (which may be branched, may have a substituent, or may be cyclic), an aralkyl group, or an acyl group. ] A method for producing a photosensitive composition comprising at least (A) a spectral sensitizer, (B) a polymerization initiator, (C) a compound capable of radical polymerization, and (D) a polymer binder, A method for producing a photosensitive composition, which comprises producing the photosensitive composition according to 1. Photosensitive lithographic printing having a photosensitive layer containing at least (A) a spectral sensitizer, (B) a polymerization initiator, (C) a radical polymerizable compound, and (D) a polymer binder on a support. A photosensitive lithographic printing plate material, wherein the photosensitive layer contains at least the photosensitive composition according to claim 1. Photosensitive lithographic printing having a photosensitive layer containing at least (A) a spectral sensitizer, (B) a polymerization initiator, (C) a radical polymerizable compound, and (D) a polymer binder on a support. A method for producing a photosensitive lithographic printing plate material according to claim 3, wherein the photosensitive lithographic printing plate material according to claim 3 is produced.