JP2007171407A - Lithographic printing original plate and plate making method for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lithographic printing original plate capable of direct drawing with laser light and excellent in thin line reproducibility and printing durability, and a plate making method for the same. <P>SOLUTION: The lithographic printing original plate has on a support a photosensitive layer containing (A) a sensitizing dye of a specific structure, (B) a polymerization initiator, (C) a polymerizable compound and (D) a binder polymer having a crosslinking group. The plate making method for the same is also provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a negative lithographic printing plate precursor capable of direct drawing with a laser beam and a plate making method thereof.

  In general, a negative lithographic printing plate precursor is developed by coating a photosensitive composition on a roughened aluminum plate or the like, exposing a desired image, and polymerizing or crosslinking the exposed portion of the photosensitive layer. Image formation is carried out by a process of insolubilizing in the solution and eluting unexposed portions of the photosensitive layer with the developer. Conventionally, as a photosensitive composition used for such a purpose, a photopolymerizable composition is well known, and a part thereof is put into practical use. In addition, recent high-sensitivity photopolymers incorporating a photoinitiating technology that is highly sensitive to visible light have been increased in sensitivity to an area used for direct plate-making with a visible laser, and are widely used as so-called CTP plates.

  In order to respond to the improvement in drawing speed as a pursuit of higher productivity, not only higher sensitivity is required, but also in terms of workability, it is easy to handle under a yellow or white light instead of a dark room. ) Is also increasing. Furthermore, a photopolymerization initiator or a photopolymerization initiation system has been designed and developed to increase the sensitivity, and the hexaarylbiimidazole photopolymerization initiator attracts attention as a highly sensitive photopolymerization initiator. . Many of such hexaarylbiimidazole photopolymerization initiators do not absorb visible light, and photosensitive compositions containing them include ultraviolet-violet lasers with wavelengths of 300 nm to 450 nm and infrared lasers with wavelengths of 800 to 1200 nm. A bright room is also possible by combining with the exposure method.

However, the sensitivity is not sufficient only with the hexaarylbiimidazole photopolymerization initiator, and it is necessary to add a sensitizing dye or a chain transfer agent. It is known that a thiol compound is generally used as the chain transfer agent (see, for example, Patent Document 1). It has also been proposed to use an oxazole compound as a sensitizing dye (see Patent Document 2). However, even with these techniques, fine line reproducibility and printing durability are still insufficient.
US Pat. No. 5,256,520 International Publication No. 2004-074930 Pamphlet

  An object of the present invention is to provide a lithographic printing plate precursor capable of direct drawing with a laser beam and excellent in fine line reproducibility and printing durability, and a plate making method thereof.

  As a result of various studies, the present inventor has found that the above problem can be solved by combining a polymerization initiation system containing a specific sensitizing dye and a binder polymer having a crosslinkable group. That is, the present invention is as follows.

  1. On the support, (A) a sensitizing dye represented by the following general formula (I) or (II), (B) a polymerization initiator, (C) a polymerizable compound, and (D) a binder having a crosslinkable group A lithographic printing plate precursor comprising a photosensitive layer containing a polymer.

Here, R < ¹ > -R < ¹⁴ > represents a hydrogen atom, an alkyl group, an alkoxy group, a cyano group, or a halogen atom each independently. However, at least one of R ^{1 to} R ¹⁰ represents an alkoxy group having 2 or more carbon atoms.
R ¹⁵ to R ³² each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a cyano group or a halogen atom. However, at least one of R ^{15 to} R ²⁴ represents an alkoxy group having 2 or more carbon atoms.

2. (D) The binder polymer having (D) a crosslinkable group is a (meth) acrylic acid copolymer having a crosslinkable group in a side chain or a polyurethane resin having a crosslinkable group in a side chain. Lithographic printing plate precursor.
3. The lithographic printing plate precursor as described in 1 or 2 above, wherein the photosensitive layer further contains (E) a chain transfer agent.

  4). (E) The lithographic printing plate precursor as described in 3 above, wherein the chain transfer agent is a thiol compound represented by the following general formula (A).

  Here, R represents an alkyl group which may have a substituent or an aryl group which may have a substituent, and A represents a 5-membered or 6-membered heterocyclic ring having a carbon atom together with an N = CN moiety. And A may further have a substituent.

5. (B) The lithographic printing plate precursor as described in any one of 1 to 4 above, wherein the polymerization initiator is a hexaarylbiimidazole compound or a metallocene compound.
6). 6. The lithographic printing plate precursor as described in any one of 1 to 5 above, which has a protective layer on the photosensitive layer.

7). The lithographic printing plate precursor as described in any one of 1 to 6 above, wherein the lithographic printing plate precursor is subjected to image development with a laser of 350 to 600 nm and then developed using a developer. .
8). The plate making method of a lithographic printing plate precursor as described in 7 above, wherein the developer contains a nonionic surfactant having a polyoxyalkylene ether group.

According to the present invention, it is possible to provide a lithographic printing plate precursor that can be directly drawn with a laser beam and has excellent fine line reproducibility and printing durability.
By using a combination of a polymerization initiating system containing a specific sensitizing dye according to the present invention and a binder polymer having a crosslinkable group, the curability of the exposed area is improved, and fine line reproducibility and printing durability are improved. Further, by adding a chain transfer agent to the photosensitive layer, a better effect is exhibited.

(Photosensitive layer)
The photosensitive layer in the lithographic printing plate precursor according to the invention comprises (A) a sensitizing dye represented by formula (I) or (II), (B) a polymerization initiator, (C) a polymerizable compound, and (D). Contains a binder polymer having a crosslinkable group. The photosensitive layer can contain (E) a chain transfer agent and other components as required.
Hereinafter, the components of the photosensitive layer will be described in detail.

(A) Sensitizing dye The sensitizing dye used in the present invention is a compound represented by the following general formula (I) or (II).

Here, R < ¹ > -R < ¹⁴ > represents a hydrogen atom, an alkyl group, an alkoxy group, a cyano group, or a halogen atom each independently. However, at least one of R ^{1 to} R ¹⁰ represents an alkoxy group having 2 or more carbon atoms.
R ¹⁵ to R ³² each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a cyano group or a halogen atom. However, at least one of R ^{15 to} R ²⁴ represents an alkoxy group having 2 or more carbon atoms.

The alkyl group and alkoxy group may have a substituent and may be linear or branched, but is preferably branched. Examples of the substituent include a halogen atom and a hydroxyl group.
Further, the alkylene chain in the alkyl group and the alkoxy group may contain an ester bond, an ether bond, or a thioether bond.

R ¹ , R ⁵ , R ⁶ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are preferably each independently a hydrogen atom, a fluorine atom or a chlorine atom, particularly R ¹ , R ⁵ , R ⁶ and R ¹⁰ are preferably a hydrogen atom, R ^{2 to} R ⁴ and R ^{7 to} R ⁹ are independently an alkoxy group, and at least two of them are preferably a branched alkoxy group having 3 to 15 carbon atoms.
R ^2, R ⁴ , R ⁷ and R ⁹ are particularly preferably a methoxy group, and R ³ and R ⁸ are each a branched alkoxy group having 3 to 15 carbon atoms.

R ¹⁵ , R ¹⁹ , R ²⁰ , R ²⁴ and R ^{25 to} R ³² are preferably each independently a hydrogen atom, a fluorine atom or a chlorine atom, and in particular, R ¹⁵ , R ¹⁹ , R ²⁰ and R ²⁴ are It is preferable that a hydrogen atom, R < ¹⁶ > -R < ¹⁸ >, R < ²¹ > -R < ²³ > is an alkoxy group independently, and at least 2 is a C3-C15 branched alkoxy group.
R ¹⁶ , R ¹⁸ , R ²¹ and R ²³ are particularly preferably a methoxy group, and R ¹⁷ and R ²² are each a branched alkoxy group having 3 to 15 carbon atoms.

  Specific examples of the sensitizing dye represented by formula (I) or (II) are shown below, but the present invention is not limited thereto.

  The sensitizing dye can be synthesized by a known method such as the method described in WO2005 / 029187.

The sensitizing dye of the present invention can be used in combination with one or more polymerization initiators.
The addition amount of the sensitizing dye is not particularly limited, but is preferably 0.2 to 25% by mass, and particularly preferably 0.5 to 15% by mass based on the total solid content of the photosensitive layer.

(B) Polymerization initiator The polymerization initiator used in the present invention includes trihalomethyl compounds, carbonyl compounds, organic peroxides, azo compounds, azide compounds, metallocene compounds, hexaarylbiimidazole compounds, and organic boron compounds. , Disulfone compounds, oxime ester compounds, and onium salt compounds. Among these, at least one selected from the group consisting of hexaarylbiimidazole compounds, onium salts, trihalomethyl compounds, and metallocene compounds is preferable, and hexaarylbiimidazole compounds are particularly preferable.

Examples of the hexaarylbiimidazole polymerization initiator include lophine dimers described in JP-B Nos. 45-37377 and 44-86516, for example, 2,2′-bis (o-chlorophenyl) -4,4 ′. , 5,5'-tetraphenylbiimidazole, 2,2'-bis (o-bromophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (o, p- Dichlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (o-chlorophenyl) -4,4', 5,5'-tetra (m-methoxyphenyl) biimidazole, 2,2'-bis (o, o'-dichlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (o-nitrophenyl) -4,4', 5 5 ' Tetraphenylbiimidazole, 2,2'-bis (o-methylphenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (o-trifluorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole and the like.

  The trihalomethyl compound is preferably trihalomethyl-s-triazine, 2,4,6-tris (trichloromethyl) -s-triazine, 2-methoxy-4,6-bis (trichloromethyl) -s-triazine, 2- Trimethyl compounds described in JP-A-58-29803 such as amino-4,6-bis (trichloromethyl) -s-triazine, 2- (P-methoxystyryl) -4,6-bis (trichloromethyl) -s-triazine and the like. Examples thereof include s-triazine derivatives having a halogen-substituted methyl group.

  Examples of the onium salt include onium salts represented by the following general formula (III).

In general formula (III), R ¹¹ , R ¹² and R ¹³ may be the same or different and each represents a hydrocarbon group having 20 or less carbon atoms which may have a substituent. Preferable substituents include a halogen atom, a nitro group, an alkyl group having 12 or less carbon atoms, an alkoxy group having 12 or less carbon atoms, or an aryloxy group having 12 or less carbon atoms.
Z ⁻ represents a counter ion selected from the group consisting of halogen ion, perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion, carboxylate ion, and sulfonate ion, preferably perchlorate ion, hexa Fluorophosphate ions, carboxylate ions, and aryl sulfonate ions.

As the titanocene compound, for example, known compounds described in JP-A Nos. 59-152396 and 61-151197 can be appropriately selected and used.
Specifically, di-cyclopentadienyl-Ti-di-chloride, di-cyclopentadienyl-Ti-bis-phenyl, di-cyclopentadienyl-Ti-bis-2,3,4,5, 6-pentafluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,3,5,6-tetrafluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2, 4,6-trifluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,6-difluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,4-difluoro Phen-1-yl, di-methylcyclopentadienyl-Ti-bis-2,3,4,5,6-pentafluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2, 3, 5, 6 Tetrafluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2,4-difluorophen-1-yl, bis (cyclopentadienyl) -bis [2,6-difluoro-3- ( Pyr-1-yl) phenyl] titanium and the like.

  Examples of the carbonyl compound include benzophenone, Michler ketone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methylbenzophenone, 2-chlorobenzophenone, 4-bromobenzophenone, 2-carboxybenzophenone and other benzophenone derivatives, 2,2-dimethoxy- 2-phenylacetophenone, 2,2-diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, α-hydroxy-2-methylphenylpropanone, 1-hydroxy-1-methylethyl- (p-isopropylphenyl) ketone, 1- Hydroxy-1- (p-dodecylphenyl) ketone, 2-methyl- (4 ′-(methylthio) phenyl) -2-morpholino-1-propanone, 1,1,1-trichloromethyl- (p-butylphenyl) Acetophenone derivatives such as ketones, thioxanthone derivatives such as thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, p- Examples thereof include benzoic acid ester derivatives such as ethyl dimethylaminobenzoate and ethyl p-diethylaminobenzoate.

  Examples of the oxime ester compound include JCS Perkin II (1979) 1653-1660), JCSPerkin II (1979) 156-162, Journal of Photopolymer Science and Technology (1995) 202-232, and JP-A 2000-66385. And compounds described in JP 2000-80068 A.

The polymerization initiator in the present invention is suitably used alone or in combination of two or more.
The amount of the polymerization initiator used in the photosensitive layer in the present invention is preferably 0.01 to 20% by mass, more preferably 0.1 to 15% by mass, based on the total solid content of the photosensitive layer. More preferably, it is 1.0 mass%-10 mass%.

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

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

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

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

  Examples of other esters include aliphatic alcohol esters described in JP-B-51-47334 and JP-A-57-196231, JP-A-59-5240, JP-A-59- Those having an aromatic skeleton described in JP-A No. 5241 and JP-A-2-226149 and those containing an amino group described in JP-A-1-165613 are also preferably used. Furthermore, the ester monomers described above can also be used as a mixture.

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

  Further, urethane-based addition polymerizable compounds produced by using an addition reaction of isocyanate and hydroxyl group are also suitable. Specific examples thereof include, for example, one molecule described in JP-B-48-41708. A vinyl urethane compound containing two or more polymerizable vinyl groups in one molecule obtained by adding a vinyl monomer containing a hydroxyl group represented by the following general formula (B) to a polyisocyanate compound having two or more isocyanate groups Etc.

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

  Also, urethane acrylates such as those described in JP-A-51-37193, JP-B-2-32293, JP-B-2-16765, JP-B-58-49860, JP-B-56- Urethane compounds having an ethylene oxide skeleton described in Japanese Patent No. 17654, Japanese Patent Publication No. 62-39417, and Japanese Patent Publication No. 62-39418 are also suitable. Furthermore, addition polymerizable compounds having an amino structure or a sulfide structure in the molecule described in JP-A-63-277653, JP-A-63-260909, and JP-A-1-105238 are used. Depending on the case, it is possible to obtain a photopolymerizable composition excellent in the photosensitive speed.

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

About these polymerizable compounds, the details of usage such as the structure, single use or combination, addition amount, etc. can be arbitrarily set according to the performance design of the final lithographic printing plate precursor. For example, it is selected from the following viewpoints.
From the viewpoint of sensitivity, a structure having a large unsaturated group content per molecule is preferable, and in many cases, a bifunctional or higher functionality is preferable. Further, in order to increase the strength of the image area, that is, the cured film, those having three or more functionalities are preferable. Further, different functional numbers and different polymerizable groups (for example, acrylic acid ester, methacrylic acid ester, styrenic compound, vinyl ether type). A method of adjusting both sensitivity and strength by using a compound) is also effective.
In addition, the compatibility and dispersibility with other components in the photosensitive layer (for example, binder polymer, polymerization initiator, colorant, etc.), the selection and use method of the polymerizable compound is an important factor. In some cases, the compatibility can be improved by using a low-purity compound or by using two or more kinds in combination. In addition, a specific structure may be selected for the purpose of improving adhesion to a support or a protective layer described later.

The polymerizable compound is preferably used in the range of 5 to 80% by mass, more preferably 25 to 75% by mass, based on the total solid content of the photosensitive layer. These may be used alone or in combination of two or more. In addition, the usage of the polymerizable compound can be arbitrarily selected from the viewpoint of polymerization inhibition with respect to oxygen, resolution, fogging, refractive index change, surface adhesiveness, etc. The layer construction and coating method such as undercoating and overcoating can also be carried out.

(D) Binder polymer In the present invention, a binder polymer is used as an essential component in order to improve the film properties and developability of the photosensitive layer. In addition, the binder polymer of the present invention is characterized by having crosslinkability in order to improve the film strength of the image area. In order to impart crosslinkability to the binder polymer, a crosslinkable functional group such as an ethylenically unsaturated bond may be introduced into the main chain or side chain of the polymer. The crosslinkable functional group may be introduced by copolymerization or may be introduced by a polymer reaction.

  Here, the crosslinkable group is a group that crosslinks the binder polymer in the process of radical polymerization reaction that occurs in the photosensitive layer when the lithographic printing plate precursor is exposed. Although it will not specifically limit if it is a group of such a function, For example, an ethylenically unsaturated bond group, an amino group, an epoxy group etc. are mentioned as a functional group which can be addition-polymerized. Moreover, the functional group which can become a radical by light irradiation may be sufficient, and as such a crosslinkable group, a thiol group, a halogen group, an onium salt structure etc. are mentioned, for example. Especially, an ethylenically unsaturated bond group is preferable and the functional group represented by the following general formula (1)-(3) is especially preferable.

In the general formula (1), R ^{1 to} R ³ each independently represents a monovalent organic group, and R ¹ is preferably a hydrogen atom or an alkyl group which may have a substituent. Among them, a hydrogen atom and a methyl group are preferable because of high radical reactivity. Further, R ^2, R ³ are each independently a hydrogen atom, a halogen atom, an amino group, a carboxyl group, an alkoxycarbonyl group, a sulfo group, a nitro group, a cyano group, an alkyl group which may have a substituent group, a substituted An aryl group that may have a group, an alkoxy group that may have a substituent, an aryloxy group that may have a substituent, an alkylamino group that may have a substituent, and a substituent An arylamino group which may have a substituent, an alkylsulfonyl group which may have a substituent, an arylsulfonyl group which may have a substituent, and the like. Among them, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, a substituent An alkyl group which may have a substituent and an aryl group which may have a substituent are preferable because of high radical reactivity.

X represents an oxygen atom, a sulfur atom, or N (R ¹² ) —, and R ¹² represents a hydrogen atom or a monovalent organic group. Here, examples of R ¹² include an alkyl group which may have a substituent. Among them, a hydrogen atom, a methyl group, an ethyl group, and an isopropyl group are preferable because of high radical reactivity.

  Here, examples of the substituent that can be introduced include an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy group, an aryloxy group, a halogen atom, an amino group, an alkylamino group, an arylamino group, a carboxyl group, an alkoxycarbonyl group, A sulfo group, a nitro group, a cyano group, an amide group, an alkylsulfonyl group, an arylsulfonyl group and the like can be mentioned.

In the general formula (2), R ^{4 to} R ⁸ each independently represents a monovalent organic group, and R ^{4 to} R ⁸ are preferably a hydrogen atom, a halogen atom, an amino group, a dialkylamino group, Carboxyl group, alkoxycarbonyl group, sulfo group, nitro group, cyano group, alkyl group which may have a substituent, aryl group which may have a substituent, alkoxy group which may have a substituent, substituted An aryloxy group which may have a group, an alkylamino group which may have a substituent, an arylamino group which may have a substituent, an alkylsulfonyl group which may have a substituent, a substituent Examples thereof include an arylsulfonyl group which may have a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, an alkyl group which may have a substituent, and an aryl group which may have a substituent. .

Examples of the substituent that can be introduced are the same as those in the general formula (1). Y represents an oxygen atom, a sulfur atom, or N (R ¹² ) —. R ¹² has the same meaning as R ¹² in general formula (1), and preferred examples are also the same.

In the general formula (3), R ⁹ is preferably a hydrogen atom or an alkyl group which may have a substituent. Among them, a hydrogen atom or a methyl group has high radical reactivity. preferable. R ¹⁰ and R ¹¹ are each independently a hydrogen atom, a halogen atom, an amino group, a dialkylamino group, a carboxyl group, an alkoxycarbonyl group, a sulfo group, a nitro group, a cyano group, or an alkyl group which may have a substituent. An aryl group which may have a substituent, an alkoxy group which may have a substituent, an aryloxy group which may have a substituent, an alkylamino group which may have a substituent, a substituent An arylamino group that may have, an alkylsulfonyl group that may have a substituent, an arylsulfonyl group that may have a substituent, and the like, among them, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, An alkyl group which may have a substituent and an aryl group which may have a substituent are preferable because of high radical reactivity.

Here, examples of the substituent that can be introduced are the same as those in the general formula (1). Further, Z is an oxygen atom, a sulfur atom, -N (R ¹³⁾ -, or a phenylene group which may have a substituent. Examples of R ¹³ include an alkyl group which may have a substituent. Among them, a methyl group, an ethyl group, and an isopropyl group are preferable because of high radical reactivity.

The binder polymer having the crosslinkable group in the side chain of the present invention not only functions as a film-forming agent for the photosensitive layer, but also needs to be dissolved in a developer, preferably an alkali developer. It is preferably a swellable organic polymer. Therefore, the binder polymer of the present invention preferably has an alkali-soluble group such as a carboxyl group in the side chain in addition to the crosslinkable group.
When the binder polymer having a crosslinkable group in the side chain is a water-soluble organic polymer, water development is possible.

Examples of the binder polymer of the present invention include those described in JP-A-59-53836 and JP-A-59-71048, that is, crosslinks such as allyl groups and (meth) acryloyl groups in the side chain. (Meth) acrylic acid copolymer, itaconic acid copolymer, crotonic acid copolymer, maleic acid copolymer, partially esterified maleic acid copolymer having a functional group.
Further, as the binder polymer of the present invention, those obtained by adding a cyclic acid anhydride to an addition polymer having a crosslinkable group and a carboxyl group in the side chain, polyurethane, an acidic cellulose derivative and a hydroxyl group are also useful. It is.
Among the above, (meth) acrylic acid copolymer and polyurethane are more preferable. In particular, the polyurethane resin can suppress the development damage of the exposed area without lowering the developability of the unexposed area even if the acid value of the photosensitive layer is low, and has both good stain resistance and high printing durability. It is preferable at the point which can do.
The polyurethane resin having a crosslinkable group in the side chain will be described in more detail below.

The polyurethane resin having a crosslinkable group in the side chain particularly preferably used in the present invention includes (i) a diisocyanate compound, (ii) a diol compound having a carboxyl group, (iii) a diisocyanate compound having a crosslinkable group, and if necessary. (Iv) It can be obtained by subjecting a diol compound having no carboxyl group to a polyaddition reaction.
The diisocyanate compound and diol compound, which are raw materials for the polyurethane resin, will be described below.

(I) Diisocyanate Compound Examples of the diisocyanate compound include a diisocyanate compound represented by the formula (4).

          OCN-L-NCO (4)

  In the formula, L represents a divalent aliphatic or aromatic hydrocarbon group which may have a substituent. If necessary, L may have other functional groups that do not react with isocyanate groups, such as carbonyl, ester, urethane, amide, and ureido groups. More specifically, L is a divalent aliphatic or aromatic hydrocarbon group which may have a single bond or a substituent (for example, alkyl, aralkyl, aryl, alkoxy and halogeno groups are preferred). Indicates. Preferably an alkylene group having 1 to 20 carbon atoms, an arylene group having 6 to 15 carbon atoms, and more preferably an alkylene group having 1 to 8 carbon atoms is shown. If necessary, L may have another functional group that does not react with an isocyanate group, for example, carbonyl, ester, urethane, amide, ureido, or ether group.

  Specific examples include the following. That is, 2,4-tolylene diisocyanate, dimer of 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate, 4,4′-diphenylmethane diisocyanate Aromatic diisocyanate compounds such as 1,5-naphthylene diisocyanate, 3,3′-dimethylbiphenyl-4,4′-diisocyanate; hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, dimer acid diisocyanate, etc. Aliphatic diisocyanate compounds; isophorone diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), methylcyclohexane-2,4 (or 2,6) diisocyanate Nitrate, cycloaliphatic diisocyanate compounds such as 1,3- (isocyanatomethyl) cyclohexane, etc .; reaction product of diol and diisocyanate such as adduct of 1 mol of 1,3-butylene glycol and 2 mol of tolylene diisocyanate The diisocyanate compound etc. which are are mentioned.

  A diisocyanate compound may be used independently and may be used in combination of 2 or more type. It is preferable to use a combination of two or more in terms of the balance between printing durability and stain resistance, and at least one aromatic diisocyanate compound (L is an aromatic group) and aliphatic diisocyanate compound (L is an aliphatic group). It is particularly preferred to use each species.

  The amount of diisocyanate used is preferably 0.8 to 1.2, more preferably 0.9 to 1.1 in terms of molar ratio to the diol compound. If the diisocyanate compound is used in excess relative to the diol compound, and the isocyanate group remains at the polymer end, the isocyanate group finally remains by treating with an alcohol or amine after completion of the urethanization reaction. It is preferable that they are synthesized in a form that does not.

(Ii) Diol compound having at least one carboxyl group As the diol compound having at least one carboxyl group, a diol compound of formula (5), (6), (7) and / or tetracarboxylic dianhydride is used. Examples thereof include compounds opened with a diol compound. The diol compound used to ring-open the carboxylic dianhydride can be used.

R ₁ represents a hydrogen atom, a substituent (for example, cyano, nitro, halogen atom (—F, —Cl, —Br, —I), —CONH ₂ , —COOR ₁₁₃ , —OR ₁₁₃ , —NHCONHR ₁₁₃ , —NHCOOR _113). , -NHCOR ₁₁₃ , -OCONHR ₁₁₃ (wherein R ₁₁₃ represents an alkyl group having 1 to 10 carbon atoms and an aralkyl group having 7 to 15 carbon atoms). And may be an alkyl, aralkyl, aryl, alkoxy, or aryloxy group, preferably a hydrogen atom, an alkyl having 1 to 8 carbon atoms, or an aryl group having 6 to 15 carbon atoms. L ₁₀ , L ₁₁ and L ₁₂ may be the same or different, and may have a single bond or a substituent (for example, alkyl, aralkyl, aryl, alkoxy and halogeno groups are preferred). A divalent aliphatic or aromatic hydrocarbon group is shown. Preferably an alkylene group having 1 to 20 carbon atoms, an arylene group having 6 to 15 carbon atoms, and more preferably an alkylene group having 1 to 8 carbon atoms is shown. If necessary, L ₁₀ , L ₁₁ , and L ₁₂ may have other functional groups that do not react with isocyanate groups, such as carbonyl, ester, urethane, amide, ureido, and ether groups. A ring may be formed by 2 or 3 of R ₁ , L ₁₀ , L ₁₁ and L ₁₂ . Ar represents a trivalent aromatic hydrocarbon group which may have a substituent, preferably an aromatic group having 6 to 15 carbon atoms.

  Specific examples of the diol compound having a carboxyl group represented by the formula (5), (6) or (7) include those shown below.

  3,5-dihydroxybenzoic acid, 2,2-bis (hydroxymethyl) propionic acid, 2,2-bis (2-hydroxyethyl) propionic acid, 2,2-bis (3-hydroxypropyl) propionic acid, Bis (hydroxymethyl) acetic acid, bis (4-hydroxyphenyl) acetic acid, 2,2-bis (hydroxymethyl) butyric acid, 4,4-bis (4-hydroxyphenyl) pentanoic acid, tartaric acid, N, N-dihydroxyethylglycine N, N-bis (2-hydroxyethyl) -3-carboxy-propionamide and the like.

  Moreover, as a preferable tetracarboxylic dianhydride used in the production | generation of the at least 1 sort (s) of diol compound which has an at least 1 carboxyl group, what is shown by Formula (8), (9), (10) is mentioned.

In the formula, L ₂₁ is a divalent aliphatic or aromatic hydrocarbon which may have a single bond or a substituent (for example, alkyl, aralkyl, aryl, alkoxy, halogeno, ester, amide groups are preferred). A group, —CO—, —SO—, —SO ₂ —, —O— or —S—; Preferably, it represents a single bond, a divalent aliphatic hydrocarbon group having 1 to 15 carbon atoms, —CO—, —SO ₂ —, —O— or —S—. R ₂ and R ₃ may be the same or different and each represents a hydrogen atom, alkyl, aralkyl, aryl, alkoxy, or halogeno group. Preferably, a hydrogen atom, a C1-C8 alkyl, a C6-C15 aryl, a C1-C8 alkoxy, or a halogeno group is shown. _{Two of} L ₂₁ , R ₂ and R ₃ may be bonded to form a ring. R ₄ and R ₅ may be the same or different and each represents a hydrogen atom, alkyl, aralkyl, aryl or halogeno group. Preferably a hydrogen atom, a C1-C8 alkyl, or a C6-C15 aryl group is shown. The L _21, R _4, although two may form a ring of R _5. L ₂₂ and L ₂₃ may be the same or different and each represents a single bond, a double bond, or a divalent aliphatic hydrocarbon group. Preferably a single bond, a double bond, or a methylene group is shown. A represents a mononuclear or polynuclear aromatic ring. An aromatic ring having 6 to 18 carbon atoms is preferable.

  Specific examples of the compound represented by the formula (8), (9) or (10) include those shown below.

That is, pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenyltetracarboxylic dianhydride, 2,3,6 , 7-Naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 4,4′-sulfonyldiphthalic dianhydride, 2,2-bis (3,4 Dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, 4,4 ′-[3,3 ′-(alkylphosphoryldiphenylene) -bis (iminocarbonyl)] diphthalic acid Aromatic tetracarboxylic dianhydrides such as dianhydrides, adducts of hydroquinone diacetate and trimetic anhydride, diacetyldiamine and trimetic anhydride; 5- (2,5-dioxote Trahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride (Dainippon Ink Chemical Co., Ltd., Epicron B-4400), 1,2,3,4-cyclopentanetetracarboxylic Alicyclic tetracarboxylic dianhydrides such as acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, tetrahydrofuran tetracarboxylic dianhydride; 1,2,3,4-butanetetra Aliphatic tetracarboxylic dianhydrides such as carboxylic dianhydride and 1,2,4,5-pentanetetracarboxylic dianhydride may be mentioned.

  By ring-opening these tetracarboxylic dianhydrides with a diol compound, (ii) at least one diol compound having at least one carboxyl group can be synthesized. However, it is also possible to synthesize the polyurethane resin of the present invention by first reacting the diol compound with (i) the diisocyanate compound and reacting this reactant with the tetracarboxylic dianhydride. Methods are also encompassed by aspects of the present invention. That is, as a method for introducing a structural unit derived from tetracarboxylic dianhydride and a diol compound into a polyurethane resin, there are the following methods.

a) A method of reacting an alcohol-terminated compound obtained by ring-opening tetracarboxylic dianhydride with a diol compound and a diisocyanate compound.
b) A method of reacting an alcohol-terminated urethane compound obtained by reacting a diisocyanate compound under an excess of a diol compound with tetracarboxylic dianhydride.

  Of the at least one diol compound having at least one carboxyl group, the compound represented by the general formula (5) is more preferable because of high solvent solubility and easy synthesis. Further, at least one diol compound having at least one carboxyl group, the polyurethane resin binder has a carboxyl group of 0.2 to 4.0 meq / g, preferably 0.3 to 3.0 meq / g, more preferably Introduced into the polyurethane resin binder in such an amount as having a range of 0.4 to 2.0 meq / g, particularly preferably 0.5 to 1.5 meq / g, most preferably 0.6 to 1.2 meq / g. . Accordingly, the content in the polyurethane resin binder having a structure derived from at least one diol compound having at least one carboxyl group is the number of carboxyl groups, what is used as the other diol component, and the acid of the polyurethane resin binder obtained. Although it is appropriately selected depending on the value, molecular weight, developer composition, pH, etc., for example, it is 5 to 45 mol%, preferably 10 to 40 mol%, more preferably 15 to 35 mol%.

(Iii) Diisocyanate compound having a crosslinkable group As the diisocyanate compound having a crosslinkable group, for example, a triisocyanate compound and a monofunctional alcohol having a crosslinkable group or 1 equivalent of a monofunctional amine compound are subjected to an addition reaction. There is a product obtained.
Examples of the triisocyanate compound include those shown below, but are not limited thereto.

  Examples of the monofunctional alcohol or monofunctional amine compound having a crosslinkable group include those shown below, but are not limited thereto.

Here, as a method for introducing a crosslinkable group into the side chain of the polyurethane resin, a method using a diisocyanate compound containing a crosslinkable group in the side chain as a raw material for producing the polyurethane resin is suitable. Examples of the diisocyanate compound that can be obtained by addition reaction of a triisocyanate compound and one equivalent of a monofunctional alcohol having a crosslinkable group or a monofunctional amine compound having a crosslinkable group in the side chain include, for example, Although the following are mentioned, it is not limited to this.

(Iv) Other diol compound As a method for introducing an unsaturated group into the side chain of the polyurethane resin, in addition to the above-described method, a diol compound containing an unsaturated group in the side chain is used as a raw material for polyurethane resin production. A method is also suitable. Such a diol compound may be a commercially available one such as trimethylolpropane monoallyl ether, a halogenated diol compound, a triol compound, an aminodiol compound, a carboxylic acid containing an unsaturated group, and an acid. It may be a compound that is easily produced by a reaction with a chloride, isocyanate, alcohol, amine, thiol, or alkyl halide compound. Specific examples of these compounds include, but are not limited to, the compounds shown below.

  Still another diol compound includes an ethylene glycol compound represented by the following general formula (A ′).

HO— (CH ₂ CH ₂ O) _n —H (A ′)
(In the formula, n represents an integer of 1 or more.)

  Moreover, the random copolymer and block copolymer of ethylene oxide and propylene oxide which have a hydroxyl group at the terminal are also mentioned.

Furthermore, bisphenol A ethylene oxide adduct (addition number of ethylene oxide 27 to 100), bisphenol F ethylene oxide adduct (ethylene oxide addition number 22 to 100), hydrogenated bisphenol A ethylene oxide adduct (addition of ethylene oxide) The ethylene oxide adduct of hydrogenated bisphenol F (the number of addition of ethylene oxide is 18 or more and 100 or less) can also be used.
More specifically, the ethylene glycol compound represented by the general formula (A ′) is preferable in terms of soiling property, n is more preferably an ethylene glycol compound having 2 to 50, and n is an ethylene glycol compound having 3 to 30. More preferably, an ethylene glycol compound having n of 4 to 10 is particularly preferable.

  Specifically, 1,2-propylene glycol, di-1,2-propylene glycol, tri-1,2-propylene glycol, tetra-1,2-propylene glycol, hexa-1,2-propylene glycol, 1, 3-propylene glycol, di-1,3-propylene glycol, tri-1,3-propylene glycol, tetra-1,3-propylene glycol, 1,3-butylene glycol, di-1,3-butylene glycol, tri- 1,3-butylene glycol, hexa-1,3-butylene glycol, polypropylene glycol having an average molecular weight of 400, polypropylene glycol having an average molecular weight of 700, polypropylene glycol having an average molecular weight of 1000, polypropylene glycol having an average molecular weight of 2000, and polypropylene having an average molecular weight of 3000 Glycol, average molecular weight 4000 polypropylene glycol, neopentyl glycol, 2-butene-1,4-diol, 2,2,4-trimethyl-1,3-pentanediol, 1,4-bis-β-hydroxyethoxycyclohexane 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, cyclohexanedimethanol, tricyclodecane dimethanol, hydrogenated bisphenol A , Hydrogenated bisphenol F, ethylene oxide adduct of bisphenol A (ethylene oxide addition number of 26 or less), ethylene oxide adduct of bisphenol F (ethylene oxide addition number of 21 or less), hydrogenated bisphenol A ethylene oxide adduct (ethyleneoxy ), Hydrogenated bisphenol F ethylene oxide adduct (ethylene oxide addition number 17 or less), bisphenol A propylene oxide adduct, bisphenol F propylene oxide adduct, hydrogenated bisphenol A propylene oxide Adduct, propylene oxide adduct of hydrogenated bisphenol F, hydroquinone dihydroxyethyl ether, p-xylylene glycol, dihydroxyethyl sulfone, bis (2-hydroxyethyl) -2,4-tolylene dicarbamate, 2,4-tolylene- Examples thereof include bis (2-hydroxyethylcarbamide), bis (2-hydroxyethyl) -m-xylylene dicarbamate, and bis (2-hydroxyethyl) isophthalate.

  Moreover, the polyether diol compound of the compound represented by Formula (a), (b), (c), (d), (e) can also be used suitably.

In the formula, R ₆ represents a hydrogen atom or a methyl group. However, in the formula (a), R ₆ represents a methyl group. X represents the following group.

  a, b, c, d, e, f, and g each represent an integer of 2 or more. Preferably it is an integer of 2-100.

  Furthermore, the polyester diol compound represented by Formula (11), (12) can also be mentioned as a specific example.

In the formula, L ₁ , L ₂ and L ₃ may be the same or different and each represents a divalent aliphatic or aromatic hydrocarbon group, and L ₄ represents a divalent aliphatic hydrocarbon group. Preferably, L ₁ , L ₂ and L ₃ each represents an alkylene group, an alkenylene group, an alkynylene group or an arylene group, and L ₄ represents an alkylene group. In addition, L ₁ , L ₂ , L ₃ , and L ₄ contain other functional groups that do not react with isocyanate groups, such as ether, carbonyl, ester, cyano, olefin, urethane, amide, ureido group, or halogen atoms. May be. n1 and n2 are each an integer of 2 or more, preferably an integer of 2 to 100.

  Furthermore, the polycarbonate diol compound represented by Formula (13) can also be mentioned as a specific example.

In the formula, L ₅ may be the same or different and each represents a divalent aliphatic or aromatic hydrocarbon group. Preferably, L ₅ represents an alkylene group, an alkenylene group, an alkynylene group or an arylene group. In addition, other functional groups that do not react with the isocyanate group, such as ether, carbonyl, ester, cyano, olefin, urethane, amide, ureido group or halogen atom may be present in L ₅ . n3 is an integer of 2 or more, preferably an integer of 2 to 100.

  Specific examples of the diol compound represented by the formula (11), (12) or (13) include those shown below. N in the specific examples is an integer of 2 or more.

  Furthermore, a diol compound that does not have a carboxyl group and may have another substituent that does not react with isocyanate can also be used.

Examples of such diol compounds include those shown below.
_{HO-L 6 -O-CO-} L 7 -CO-O-L 6 -OH (14)
_{HO-L 7 -CO-O-} L 6 -OH (15)

In the formula, L ₆ and L ₇ may be the same as or different from each other, and a substituent (eg, alkyl, aralkyl, aryl, alkoxy, aryloxy, halogen atom (—F, —Cl, —Br, —I), A divalent aliphatic hydrocarbon group, an aromatic hydrocarbon group or a heterocyclic group which may have a group. If necessary, L ₆ and L ₇ may have another functional group that does not react with an isocyanate group, for example, carbonyl, ester, urethane, amide, ureido group and the like. Note that L ₆ and L ₇ may form a ring.

  Specific examples of the compound represented by the formula (14) or (15) include those shown below.

  Moreover, the diol compound shown below can also be used conveniently.

In the formula, R ₇ and R ₈ may be the same or different, and may be an alkyl group which may have a substituent, preferably cyano, nitro, halogen atom (—F, —Cl, —Br, —I _{), - CONH 2, -COOR,} -OR, ( wherein, R represents may be the same or different from each other, alkyl groups having 1 to 10 carbon atoms, ants having 7 to 15 carbon atoms - group, aralkyl group An alkyl group having 1 to 10 carbon atoms which may have each group as a substituent.

  Specific examples of the diol compound represented by the formula (16) include those shown below.

Examples of the formula (17) include 2-butyne-1,4-diol, and examples of the formula (18) include cis-2-butene-1,4-diol and trans-2-butene-1,4-diol. It is done.
Moreover, the diol compound shown to following formula (19), (20) can also be used conveniently.
_{HO-L 8 -NH-CO-} L 9 -CO-NH-L 8 -OH (19)
_{HO-L 9 -CO-NH-} L 8 -OH (20)

In the formula, L ₈ and L ₉ may be the same as or different from each other, and a substituent (eg, alkyl, aralkyl, aryl, alkoxy, aryloxy, halogen atom (—F, —Cl, —Br, —I), A divalent aliphatic hydrocarbon group, an aromatic hydrocarbon group or a heterocyclic group which may have a group. If necessary, L ₈ and L ₉ may have other functional groups that do not react with isocyanate groups, such as carbonyl, ester, urethane, amide, ureido groups and the like. Note that L ₈ and L ₉ may form a ring.

  Specific examples of the compound represented by the formula (19) or (20) include those shown below.

Furthermore, diol compounds represented by the following formulas (21) and (22) can also be suitably used.
_{HO-Ar 2 - (L 16} -Ar 3) n -OH (21)
_{HO-Ar 2 -L 16 -OH (} 22)

In the formula, L ₁₆ represents a divalent aliphatic hydrocarbon group which may have a substituent (eg, alkyl, aralkyl, aryl, alkoxy, aryloxy and halogeno groups are preferable). If necessary, L ₁₆ may have another functional group that does not react with an isocyanate group, such as an ester, urethane, amide, or ureido group.

Ar ₂ and Ar ₃ may be the same or different and each represents a divalent aromatic hydrocarbon group which may have a substituent, preferably an aromatic group having 6 to 15 carbon atoms. n represents an integer of 0 to 10.
Specific examples of the diol compound represented by the formula (21) or (22) include those shown below.

  That is, catechol, resorcin, hydroquinone, 4-methylcatechol, 4-t-butylcatechol, 4-acetylcatechol, 3-methoxycatechol, 4-phenylcatechol, 4-methylresorcin, 4-ethylresorcin, 4-t-butyl Resorcin, 4-hexyl resorcin, 4-chlororesorcin, 4-benzyl resorcin, 4-acetyl resorcin, 4-carbomethoxy resorcin, 2-methyl resorcin, 5-methyl resorcin, t-butyl hydroquinone, 2,5-di-t -Butylhydroquinone, 2,5-di-t-amylhydroquinone, tetramethylhydroquinone, tetrachlorohydroquinone, methylcarboaminohydroquinone, methylureidohydroquinone, methylthiohydroquinone, benzonor Runene-3,6-diol, bisphenol A, bisphenol S, 3,3′-dichlorobisphenol S, 4,4′-dihydroxybenzophenone, 4,4′-dihydroxybiphenyl, 4,4′-thiodiphenol, 2, 2′-dihydroxydiphenylmethane, 3,4-bis (p-hydroxyphenyl) hexane, 1,4-bis (2- (p-hydroxyphenyl) propyl) benzene, bis (4-hydroxyphenyl) methylamine, 1,3 -Dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 1,5-dihydroxyanthraquinone, 2-hydroxybenzyl alcohol, 4-hydroxybenzyl alcohol, 2-hydroxy-3, 5-di-t-butylbenzyl Alcohol, 4-hydroxy-3,5-di-t-butylbenzyl alcohol, 4-hydroxyphenethyl alcohol, 2-hydroxyethyl-4-hydroxybenzoate, 2-hydroxyethyl-4-hydroxyphenyl acetate, resorcin mono-2- And hydroxyethyl ether. The diol compound shown below can also be used conveniently.

(V) Other amino group-containing compound In the polyurethane resin binder of the present invention, the amino group-containing compound represented by the following formulas (31) and (32) is further combined and reacted with a diisocyanate compound to form a urea structure to form a polyurethane resin. It may be incorporated into the structure.

In the formula, R ₁₀₆ and R _{106 ′} may be the same or different, and each may be a hydrogen atom, a substituent (for example, alkoxy, halogen atom (—F, —Cl, —Br, —I), ester, carboxyl group, etc. An alkyl group, an aralkyl group and an aryl group which may have a hydrogen atom, a C1-C8 alkyl which may have a carboxyl group as a substituent, An aryl group having 6 to 15 carbon atoms is shown. L ₁₇ has a substituent (for example, each group such as alkyl, aralkyl, aryl, alkoxy, aryloxy, halogen atom (—F, —Cl, —Br, —I), carboxyl group and the like is included). And a divalent aliphatic hydrocarbon group, aromatic hydrocarbon group or heterocyclic group. If necessary, L ₁₇ may have another functional group that does not react with an isocyanate group, such as a carbonyl group, an ester group, a urethane group or an amide group. Two of R ₁₀₆ , L ₁₇ and R _{106 ′} may form a ring.

  Specific examples of the compounds represented by the formulas (31) and (32) include those shown below.

  That is, ethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, dodecamethylenediamine, propane-1,2-diamine, bis (3-aminopropyl) methylamine, 1 , 3-bis (3-aminopropyl) tetramethylsiloxane, piperazine, 2,5-dimethylpiperazine, N- (2-aminoethyl) piperazine, 4-amino-2,2-6,6-tetramethylpiperidine, N , N-dimethylethylenediamine, lysine, L-cystine, isophoronediamine, and the like; o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,4-tolylenediamine, benzidine, o- Toluidine, o-dianisidine, 4-nitro-m-phenylenediamine, 2,5-dimethoxy-p-phenylenediamine, bis- (4-aminophenyl) sulfone, 4-carboxy-o-phenylenediamine, 3-carboxy-m -Aromatic diamine compounds such as phenylenediamine, 4,4'-diaminophenyl ether, 1,8-naphthalenediamine, etc .; 2-aminoimidazole, 3-aminotriazole, 5-amino-1H-tetrazole, 4-aminopyrazole 2-aminobenzimidazole, 2-amino-5-carboxy-triazole, 2,4-diamino-6-methyl-S-triazine, 2,6-diaminopyridine, L-histidine, DL-tryptophan, adenine, etc. Heterocyclic amine compounds; ethanolamine, N- Tylethanolamine, N-ethylethanolamine, 1-amino-2-propanol, 1-amino-3-propanol, 2-aminoethoxyethanol, 2-aminothioethoxyethanol, 2-amino-2-methyl-1-propanol P-aminophenol, m-aminophenol, o-aminophenol, 4-methyl-2-aminophenol, 2-chloro-4-aminophenol, 4-methoxy-3-aminophenol, 4-hydroxybenzylamine, 4 -Amino-1-naphthol, 4-aminosalicylic acid, 4-hydroxy-N-phenylglycine, 2-aminobenzyl alcohol, 4-aminophenethyl alcohol, 2-carboxy-5-amino-1-naphthol, L-tyrosine, etc. Such as amino alcohol or amino Lumpur compound.

  As the binder polymer of the present invention, in addition to the polyurethane resin obtained by introducing a crosslinkable group into the side chain during the synthesis of polyurethane, a polymer having a carboxyl group as described in JP-A-2003-270775 is used. A polyurethane resin obtained by introducing a crosslinkable group by reaction can also be used.

  The molecular weight of the binder polymer in the present invention is appropriately determined from the viewpoint of image formability and printing durability. The molecular weight is preferably in the range of 2,000 to 1,000,000, more preferably 5,000 to 500,000, and still more preferably 10,000 to 200,000.

  The binder polymer used in the present invention may be used alone or in combination of two or more. Further, one or more other binder polymers having no crosslinkable group may be used in combination as a mixture. As the binder polymer that can be used in combination, a conventionally known alkali-soluble or swellable binder can be used without limitation, and specifically, an acrylic main chain binder, a urethane binder, or the like often used in the industry is preferably used.

  Although the total amount of the binder polymer having a crosslinkable group in the photosensitive layer and the binder polymer that may be used in combination can be determined as appropriate, it is generally 10 to 90 with respect to the total mass of nonvolatile components in the photosensitive layer. It is mass%, Preferably it is 20-80 mass%, More preferably, it is the range of 30-70 mass%.

(E) Chain transfer agent The photosensitive layer of the invention preferably contains a chain transfer agent. Chain transfer agents contribute to improved sensitivity and storage stability. As the compound that acts as a chain transfer agent, for example, a compound group having SH, PH, SiH, GeH in the molecule is used. These can donate hydrogen to low-activity radical species to generate radicals, or can be oxidized and then deprotonated to generate radicals.

In the photosensitive layer of the present invention, in particular, a thiol compound (for example, 2-mercaptobenzimidazoles) can be preferably used as a chain transfer agent.
Especially, the thiol compound represented by the following general formula (A) is used especially suitably. By using this thiol compound as a chain transfer agent, the problem of odor and sensitivity reduction due to evaporation from the photosensitive layer and diffusion to other layers are avoided, and it has excellent storage stability and high sensitivity and high printing durability. A lithographic printing plate precursor is obtained.

  In the general formula (A), R represents an alkyl group which may have a substituent or an aryl group which may have a substituent, and A is a 5-membered or 6-membered carbon atom having an N═C—N moiety. Represents a group of atoms forming a member heterocycle, and A may further have a substituent.

  More preferably, those represented by the following general formula (IV) or general formula (V) are used.

  In general formulas (IV) and (V), R represents an alkyl group which may have a substituent or an aryl group which may have a substituent, and X represents a halogen atom, an alkoxyl group or a substituent. The alkyl group which may have or the aryl group which may have a substituent is represented.

  Specific examples of the compound represented by formula (A) are shown below, but the present invention is not limited thereto.

The amount of these chain transfer agents (thiol compounds) used is preferably 0.01 to 20% by mass, more preferably 0.1 to 15% by mass, based on the total solid content of the photosensitive layer. More preferably, it is 1.0-10 mass%.

(F) Other additives It is desirable to add a small amount of a thermal polymerization inhibitor in order to prevent unnecessary thermal polymerization in the photosensitive layer during the production or storage of the lithographic printing plate precursor. Suitable thermal polymerization inhibitors include haloid quinone, p-methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4-thiobis (3-methyl-6-t-butylphenol) 2,2′-methylenebis (4-methyl-6-tert-butylphenol), N-nitrosophenylhydroxylamine primary cerium salt, N-nitrosophenylhydroxylamine aluminum salt and the like.
The addition amount of the thermal polymerization inhibitor is preferably about 0.01% by mass to about 5% by mass with respect to the total solid content constituting the photosensitive layer.
If necessary, a higher fatty acid derivative such as behenic acid or behenic acid amide is added to the photosensitive layer of the present invention to prevent polymerization inhibition due to oxygen, and the surface of the photosensitive layer is dried during coating. May be unevenly distributed. The addition amount of the higher fatty acid derivative or the like is preferably about 0.5% by mass to about 10% by mass with respect to the total solid content constituting the photosensitive layer.
Further, a coloring agent may be added for the purpose of coloring the photosensitive layer. Examples of the colorant include phthalocyanine pigments (CIPigment Blue 15: 3, 15: 4, 15: 6, etc.), azo pigments, pigments such as carbon black and titanium oxide, ethyl violet, crystal violet, azo dye, anthraquinone. There are dyes and cyanine dyes. The addition amount of the colorant is preferably about 0.5% by mass to about 20% by mass based on the total solid content of the photosensitive layer. In addition, in order to improve the physical properties of the cured film, an additive such as an inorganic filler or a plasticizer such as dioctyl phthalate, dimethyl phthalate, or tricresyl phosphate may be added. These addition amounts are preferably 10% by mass or less based on the total solid content of the photosensitive layer.

[Formation of photosensitive layer]
In coating the photosensitive layer, the above components are dissolved in a solvent to prepare a coating solution. Solvents used here include acetone, methyl ethyl ketone, cyclohexane, ethyl acetate, ethylene dichlorite, tetrahydrofuran, toluene, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether. , Acetylacetone, cyclohexanone, diacetone alcohol, ethylene glycol monomethyl ether acetate, ethylene glycol ethyl ether acetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether acetate, 3-methoxypropanol, methoxymethoxyethanol, diethylene glycol monomethyl ether, di Ethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate-3-methoxypropyl acetate, N, N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, methyl lactate, lactic acid There are organic solvents such as ethyl. A solvent can be used individually or in mixture.
The density | concentration of the solid content in a coating solution is 1-50 mass% normally.

  In addition, a surfactant can be added to improve the coating surface quality.

The coverage of the photosensitive layer in the weight after drying is generally about 0.1 to about 10 g / m ^2, preferably from 0.3 to 5 g / m ^2, more preferably 0.5 to 3 g / m ^2.

[Protective layer]
The lithographic printing plate precursor according to the invention is preferably provided with a protective layer (oxygen blocking layer) on the photosensitive layer in order to block diffusion and penetration of oxygen that hinders the polymerization reaction during exposure. The protective layer used in the present invention preferably has an oxygen permeability A at 25 ° C. and 1 atm of 1.0 ≦ A ≦ 20 (mL / m ² · day). When the oxygen permeability A is extremely low at less than 1.0 (mL / m ² · day), unnecessary polymerization reaction occurs at the time of production and raw storage, and unnecessary fogging and image streaking occur during image exposure. The problem that fatness arises arises. Conversely, when the oxygen permeability A exceeds 20 (mL / m ² · day) and is too high, the sensitivity is lowered. The oxygen permeability A is more preferably in the range of 1.5 ≦ A ≦ 12 (mL / m ² · day), more preferably 2.0 ≦ A ≦ 8.0 (mL / m ² · day). In addition to the oxygen permeability described above, the properties desired for the protective layer further do not substantially inhibit the transmission of light used for exposure, have excellent adhesion to the photosensitive layer, and are easy in the development process after exposure. It is desirable that it can be removed. The device concerning such a protective layer has been conventionally made, and is described in detail in US Pat. No. 3,458,311 and JP-B-55-49729.

  As a material that can be used for the protective layer, for example, a water-soluble polymer compound having relatively excellent crystallinity is preferably used. Specifically, polyvinyl alcohol, vinyl alcohol / vinyl phthalate copolymer, vinyl acetate / vinyl are used. Examples include water-soluble polymers such as alcohol / vinyl phthalate copolymer, vinyl acetate / crotonic acid copolymer, polyvinyl pyrrolidone, acidic celluloses, gelatin, gum arabic, polyacrylic acid, and polyacrylamide. Or they can be mixed. Of these, the use of polyvinyl alcohol as the main component gives the best results in terms of basic properties such as oxygen barrier properties and development removability.

  The polyvinyl alcohol used for the protective layer may be partially substituted with an ester, an ether, or an acetal as long as it contains an unsubstituted vinyl alcohol unit for having necessary oxygen barrier properties and water solubility. Similarly, some of them may have other copolymer components. Specific examples of the polyvinyl alcohol include those having a hydrolysis rate of 71 to 100 mol% and a polymerization repeating unit in the range of 300 to 2400. Specifically, Kuraray Co., Ltd. PVA-105, PVA-110, PVA-117, PVA-117H, PVA-120, PVA-124, PVA-124H, PVA-CS, PVA-CST, PVA-HC, PVA-203, PVA-204, PVA-205, PVA-210, PVA-217, PVA-220, PVA-224, PVA-217EE, PVA-217E, PVA-220E, PVA-224E, PVA-405, PVA- 420, PVA-613, L-8 and the like, and these can be used alone or in combination. In a preferred embodiment, the content of polyvinyl alcohol in the protective layer is 20 to 95% by mass, and more preferably 30 to 90% by mass.

  As a component used by mixing with polyvinyl alcohol, polyvinyl pyrrolidone or a modified product thereof is preferable from the viewpoint of oxygen barrier properties and development removability, and the content in the protective layer is 3.5 to 80% by mass, preferably 10 to 60%. It is 15 mass%, More preferably, it is 15-30 mass%.

  Components of the protective layer (selection of PVA, use of additives), coating amount, and the like are selected in consideration of fogging, adhesion, and scratch resistance in addition to oxygen barrier properties and development removability. In general, the higher the hydrolysis rate of the PVA used (the higher the content of the unsubstituted vinyl alcohol unit in the protective layer), the thicker the film thickness, the higher the oxygen barrier property, which is advantageous in terms of sensitivity. The molecular weight of the polymer compound such as polyvinyl alcohol (PVA) can be in the range of 2000 to 10 million, preferably in the range of 20,000 to 3 million.

As another composition of the protective layer, glycerin, dipropylene glycol and the like can be added in an amount corresponding to several mass% with respect to the polymer compound to give flexibility. Also, sodium alkyl sulfate, sodium alkyl sulfonate Anionic surfactants such as: amphoteric surfactants such as alkylaminocarboxylates and alkylaminodicarboxylates; nonionic surfactants such as polyoxyethylene alkylphenyl ethers are added to the polymer compound by several mass% be able to. The thickness of the protective layer is suitably 0.5 to 5 μm, particularly 1 to 3 μm.

  In addition, adhesion to the photosensitive layer and scratch resistance are extremely important in handling the planographic printing plate precursor. That is, when a hydrophilic layer made of a water-soluble polymer is laminated on an oleophilic photosensitive layer, film peeling due to insufficient adhesion tends to occur, and the peeled part causes defects such as poor film hardening due to inhibition of oxygen polymerization. On the other hand, various proposals have been made to improve the adhesion between these two layers. For example, in U.S. Patent Application No. 292,501 and U.S. Patent Application No. 44,563, an acrylic emulsion or a water-insoluble vinyl pyrrolidone-vinyl acetate copolymer is contained in a hydrophilic polymer mainly composed of polyvinyl alcohol. It is described that sufficient adhesiveness can be obtained by mixing 20 to 60% by mass and laminating on a photosensitive layer. Any of these known techniques can be applied to the protective layer in the present invention. Such a coating method for the protective layer is described in detail in, for example, US Pat. No. 3,458,311 and Japanese Patent Publication No. 55-49729.

The coating amount of the protective layer is a dry weight, generally 0.1 to 10 g / m ^2, preferably from 0.5 to 5 g / m ^2.

[Support]
The support used for the lithographic printing plate precursor according to the invention is not particularly limited as long as it is a dimensionally stable plate. For example, paper, paper laminated with plastic (eg, polyethylene, polypropylene, polystyrene, etc.), metal plate (eg, aluminum, zinc, copper, etc.), plastic film (eg, cellulose diacetate, cellulose triacetate, cellulose propionate) Cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc.), and paper or plastic films on which the above-mentioned metals are laminated or deposited. Preferable supports include a polyester film and an aluminum plate. Among these, an aluminum plate that has good dimensional stability and is relatively inexpensive is preferable.

  The aluminum plate is a pure aluminum plate, an alloy plate containing aluminum as a main component and containing a trace amount of different elements, or a plastic laminated on a thin film of aluminum or an aluminum alloy. Examples of foreign elements contained in the aluminum alloy include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, and titanium. The content of foreign elements in the alloy is preferably 10% by mass or less. In the present invention, a pure aluminum plate is preferable, but completely pure aluminum is difficult to manufacture in terms of refining technology, and therefore may contain a slightly different element. The composition of the aluminum plate is not specified, and a publicly known material can be used as appropriate.

  The thickness of the support is preferably from 0.1 to 0.6 mm, more preferably from 0.15 to 0.4 mm, and even more preferably from 0.2 to 0.3 mm.

  Prior to using the aluminum plate, it is preferable to perform a surface treatment such as roughening treatment or anodizing treatment. By the surface treatment, it becomes easy to improve hydrophilicity and secure adhesion between the photosensitive layer and the support. Prior to roughening the aluminum plate, a degreasing treatment with a surfactant, an organic solvent, an alkaline aqueous solution or the like for removing rolling oil on the surface is performed as desired.

The surface roughening treatment of the aluminum plate is performed by various methods. For example, mechanical surface roughening treatment, electrochemical surface roughening treatment (surface roughening treatment for dissolving the surface electrochemically), chemical treatment, etc. Surface roughening treatment (roughening treatment that chemically selectively dissolves the surface).
As a method for the mechanical surface roughening treatment, a known method such as a ball polishing method, a brush polishing method, a blast polishing method, or a buff polishing method can be used.
Examples of the electrochemical surface roughening treatment include a method in which an alternating current or a direct current is used in an electrolytic solution containing an acid such as hydrochloric acid or nitric acid. Another example is a method using a mixed acid as described in JP-A-54-63902.

  The surface-roughened aluminum plate is subjected to an alkali etching treatment using an aqueous solution of potassium hydroxide, sodium hydroxide or the like, if necessary, further neutralized, and if desired, wear resistant. In order to increase the anodic oxidation treatment.

As the electrolyte used for the anodizing treatment of the aluminum plate, various electrolytes that form a porous oxide film can be used. In general, sulfuric acid, hydrochloric acid, oxalic acid, chromic acid or a mixed acid thereof is used. The concentration of these electrolytes is appropriately determined depending on the type of electrolyte.
The conditions for anodizing treatment vary depending on the electrolyte used and cannot be specified in general. In general, however, the electrolyte concentration is 1 to 80% by mass solution, the liquid temperature is 5 to 70 ° C., and the current density is 5 to 60 A / day. dm ² , voltage 1 to 100 V, and electrolysis time 10 seconds to 5 minutes are preferable. The amount of the anodized film formed is preferably from 1.0 to 5.0 g / m ^2, and more preferably 1.5 to 4.0 g / m ^2. Within this range, good printing durability and good scratch resistance of the non-image area of the lithographic printing plate can be obtained.

  After the anodizing treatment, the surface of the aluminum plate is subjected to a hydrophilic treatment as necessary. The hydrophilization treatment is described in US Pat. Nos. 2,714,066, 3,181,461, 3,280,734, and 3,902,734. There are such alkali metal silicate methods. In this method, the support is immersed in an aqueous solution such as sodium silicate or electrolytically treated. In addition, the treatment with potassium zirconate fluoride described in JP-B 36-22063, U.S. Pat. Nos. 3,276,868, 4,153,461 and 4,689, And a method of treating with polyvinylphosphonic acid as described in each specification of No.272.

The support preferably has a center line average roughness of 0.10 to 1.2 μm. Within this range, good adhesion to the photosensitive layer, good printing durability and good stain resistance can be obtained.
The color density of the support is preferably 0.15 to 0.65 as the reflection density value. Within this range, good image formability by preventing halation during image exposure and good plate inspection after development can be obtained.

[Middle layer]
After the above treatment, in the present invention, an intermediate layer (sometimes referred to as an undercoat layer) may be provided for the purpose of improving the adhesion and soiling between the photosensitive layer and the support. Good. For example, a water-soluble resin such as polyvinyl phosphonic acid, a polymer or copolymer having a sulfo group in the side chain, polyacrylic acid, a water-soluble metal salt (for example, zinc borate) or a yellow dye, an amine salt or the like is primed. Those are also suitable. 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-7-159983 is covalently used.

As another preferred example, a substrate provided with a water-resistant hydrophilic layer as a surface layer on an arbitrary support can be raised. Examples of such a surface layer include a layer composed of an inorganic pigment and a binder described in US Pat. No. 3,055,295 and JP-A-56-13168, and a hydrophilic swelling described in JP-A-9-80744. A layer, a sol-gel film made of titanium oxide, polyvinyl alcohol, silicic acid or the like described in JP-A-8-507727 can be raised. These hydrophilic treatments are performed to make the surface of the support hydrophilic, in order to prevent harmful reactions of the photosensitive layer provided thereon, and to improve the adhesion of the photosensitive layer, etc. It is to be given.

  Other examples of the intermediate layer include JP-B-50-7481, JP-A-54-72104, JP-A-59-101651, JP-A-60-149491, JP-A-60-232998, JP-A-3 JP-A-56177, JP-A-4-282737, JP-A-5-16558, JP-A-5-246171, JP-A-7-314937, JP-A-8-202025, JP-A-8-320551, JP-A-9- JP 34104, JP 9-236911, JP 9-269593, JP 10-69092, JP 10-115931, JP 10-161317, JP 10-260536, JP 10-282682. JP-A-11-84684, JP-A-11-38635, JP-A-11-38629, JP-A-10-282645, JP-A-1 -301262, JP-A-11-24277, JP-A-11-109641, JP-A-10-319600, JP-A-11-327152, JP2000-10292, JP2000-235254, JP2000- No. 352824, JP-A-2001-209170, and the like.

[Back coat]
After the surface treatment is applied to the support or the intermediate layer is formed, a back coat can be provided on the back surface of the support, if necessary.
Examples of the back coat include hydrolysis and polycondensation of organic polymer compounds described in JP-A-5-45885, organometallic compounds or inorganic metal compounds described in JP-A-6-35174. A coating layer made of a metal oxide obtained in this manner is preferred. Among them, it is inexpensive to use a silicon alkoxy compound such as Si (OCH ₃ ) ₄ , Si (OC ₂ H ₅ ) ₄ , Si (OC ₃ H ₇ ) ₄ , Si (OC ₄ H ₉ ) _4. It is preferable in terms of easy availability.

[Plate making method]
Next, the plate making method of the lithographic printing plate precursor according to the invention will be described in detail. The above-described lithographic printing plate precursor is subjected to image exposure and then developed with an alkaline aqueous solution. Below, the developing solution used for the plate making method of this invention is demonstrated.

(Developer)
The developer used in the plate making method of the lithographic printing plate precursor according to the present invention is not particularly limited. For example, a developer containing an inorganic alkali salt and a surfactant and usually having a pH of 11.0 to 12.7. Preferably used.

  The inorganic alkali salt can be used as appropriate. For example, sodium hydroxide, potassium, ammonium, lithium, sodium silicate, potassium, ammonium, lithium, tribasic sodium phosphate, potassium, ammonium Inorganic alkaline agents such as sodium carbonate, potassium, ammonium, sodium hydrogen carbonate, potassium, ammonium, sodium borate, potassium, and ammonium. These may be used alone or in combination of two or more.

In the case of using silicate, developability can be achieved by adjusting the mixing ratio and concentration of silicon oxide SiO ₂ which is a component of silicate and alkali oxide M ₂ O (M represents an alkali metal or ammonium group). Can be easily adjusted. Among the alkaline aqueous solutions, those having a mixing ratio (SiO ₂ / M ₂ O: molar ratio) of the silicon oxide SiO ₂ and the alkali oxide M ₂ O of 0.5 to 3.0 are preferable, and 1.0 to 2 0.0 is preferred. The addition amount of the SiO ₂ / M ₂ O is preferably 1 to 10% by mass, more preferably 3 to 8% by mass, and most preferably 4 to 7% by mass with respect to the mass of the alkaline aqueous solution. When this concentration is within the above-mentioned range, there is no decrease in developability and processing capacity, no precipitation or crystal formation, no gelation during neutralization during waste liquid, and no trouble in waste liquid processing.

  In addition, an organic alkali agent may be supplementarily used in order to finely adjust the alkali concentration and supplement the solubility of the photosensitive layer. Examples of the organic alkali agent include monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, Examples thereof include diisopropanolamine, ethyleneimine, ethylenediamine, pyridine, tetramethylammonium hydroxide and the like. These alkali agents are used alone or in combination of two or more.

  The surfactant can be used as appropriate. For example, nonionic surfactants having a polyoxyalkylene ether group, polyoxyethylene alkyl esters such as polyoxyethylene stearate, sorbitan monolaurate, sorbitan monostearate Nonionic surfactants such as sorbitan alkyl esters such as sorbitan distearate, sorbitan monooleate, sorbitan sesquioleate, sorbitan trioleate, and monoglyceride alkyl esters such as glycerol monostearate and glycerol monooleate; Alkyl benzene sulfonates such as sodium acetate, sodium butyl naphthalene sulfonate, sodium pentyl naphthalene sulfonate, sodium hexyl naphthalene sulfonate Anion interfaces such as alkyl naphthalene sulfonates such as sodium, sodium octyl naphthalene sulfonate, alkyl sulfates such as sodium lauryl sulfate, alkyl sulfonates such as sodium dodecyl sulfonate, and sulfosuccinate esters such as sodium dilauryl sulfosuccinate Activators: Alkyl betaines such as lauryl betaine and stearyl betaine, amphoteric surfactants such as amino acids, and the like can be mentioned. Particularly preferred are nonionic surfactants having a polyoxyalkylene ether group.

  As the surfactant containing a polyoxyalkylene ether group, one having a structure of the following general formula (VI) is preferably used.

R ₄₀ —O— (R ₄₁ —O) _pH (VI)

In the formula, R ₄₀ is an alkyl group having 3 to 15 carbon atoms, an aromatic hydrocarbon group having 6 to 15 carbon atoms, or a heteroaromatic ring group having 4 to 15 carbon atoms (in addition, the substituent is 1 to 20 carbon atoms). An alkylene group, a halogen atom such as Br, Cl, or I, an aromatic hydrocarbon group having 6 to 15 carbon atoms, an aralkyl group having 7 to 17 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an alkyl group having 2 to 20 carbon atoms An alkoxy-carbonyl group and an acyl group having 2 to 15 carbon atoms.), R ₄₁ represents an alkylene group having 1 to 100 carbon atoms, and p represents an integer of 1 to 100. Each of these groups may have a substituent, and examples of the substituent include an alkyl group having 1 to 20 carbon atoms and an aromatic hydrocarbon group having 6 to 15 carbon atoms.

In the definition of the above formula (VI), specific examples of the “aromatic hydrocarbon group” include phenyl group, tolyl group, naphthyl group, anthryl group, biphenyl group, phenanthryl group and the like, and “heteroaromatic ring” Specific examples of the “group” include furyl group, thionyl group, oxazolyl group, imidazolyl group, pyranyl group, pyridinyl group, acridinyl group, benzofuranyl group, benzothionyl group, benzopyranyl group, benzooxazolyl group, benzoimidazolyl group, and the like. It is done.

In addition, the part of (R ₄₁ —O) p in the formula (VI) may be two or three groups as long as it is in the above range. Specific examples include random or block combinations of ethyleneoxy and propyleneoxy groups, ethyleneoxy and isopropyloxy groups, ethyleneoxy and butyleneoxy groups, ethyleneoxy groups and isobutylene groups, and the like. . In the present invention, the surfactant having a polyoxyalkylene ether group is used alone or in combination, and it is effective to add 1 to 30% by mass, preferably 2 to 20% by mass in the developer. If the addition amount is small, the developability may be deteriorated. On the other hand, if the amount is too large, the development damage becomes strong and the printing durability of the printing plate may be deteriorated.

  Examples of the nonionic surfactant having a polyoxyalkylene ether group represented by the above formula (VI) include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, and polyoxyethylene stearyl ether. Polyoxyethylene aryl ethers such as polyoxyethylene phenyl ether and polyoxyethylene naphthyl ether, polyoxyethylene alkyl aryl ethers such as polyoxyethylene methyl phenyl ether, polyoxyethylene octyl phenyl ether and polyoxyethylene nonyl phenyl ether Kind.

  Surfactants can be used alone or in combination.

  The pH of the developer used in the plate-making method of the present invention is usually 11.0 to 12.7, preferably 11.5 to 12.5, from the viewpoint of damage during image formation and development of the exposed area.

  Moreover, it is preferable that the electrical conductivity of the developing solution used by this invention is 3-30 mS / cm. If the ratio is lower than normal, the elution of the photosensitive layer components on the surface of the aluminum plate support becomes difficult and printing may be accompanied by stains. Conversely, if the range is exceeded, the salt concentration is high, so the elution rate of the photosensitive layer is increased. This is because the film is extremely slow and a remaining film may be formed in the unexposed area. Particularly preferred conductivity is in the range of 5-20 mS / cm.

(Exposure and development processing)
The lithographic printing plate precursor in the present invention is, for example, a carbon arc lamp, a high-pressure mercury lamp, a xenon lamp, a metal halide lamp, a fluorescent lamp, a tungsten lamp, a halogen lamp, a helium cadmium laser, an argon ion laser, an FD / YAG laser, a helium neolaser, An image can be formed on the surface of the aluminum plate support by image exposure with a conventionally known actinic ray such as a semiconductor laser (350 nm to 600 nm) and then developing with a developer. As the exposure light source, a laser of 350 to 600 nm is preferable.
A heating process for 1 second to 5 minutes may be performed at a temperature of 50 ° C. to 140 ° C. for the purpose of increasing the curing rate of the photosensitive layer between image exposure and development. When the heating temperature is in the above range, there is an effect of increasing the curing rate, and a residual film due to dark polymerization in the unexposed area does not occur.

  When a protective layer is provided on the photosensitive layer of the lithographic printing plate precursor according to the invention, using a developer, a method of simultaneously removing the protective layer and removing the unexposed portion of the photosensitive layer, or A method is known in which the protective layer is first removed with water or warm water, and then the unexposed photosensitive layer is removed by development. These water or warm water can contain a preservative described in JP-A-10-10754, an organic solvent described in JP-A-8-278636, and the like.

  The developer used for developing the lithographic printing plate precursor according to the invention preferably contains a nonionic surfactant having a polyoxyalkylene ether group.

  The development of the lithographic printing plate precursor in the present invention with the developer is carried out by immersing the exposed lithographic printing plate precursor in the developer at a temperature of about 0 to 60 ° C., preferably about 15 to 40 ° C., according to a conventional method. For example, rubbing with a brush.

Further, when developing using an automatic developing machine, the developing solution becomes fatigued according to the amount of processing, so that the processing capability may be restored using a replenishing solution or a fresh developing solution. The lithographic printing plate precursor thus developed is usually washed with water, interface, as described in JP-A Nos. 54-8002, 55-1115045 and 59-58431. It is post-treated with a rinsing solution containing an active agent and the like, a desensitizing solution containing gum arabic, starch derivatives and the like. In the present invention, these treatments can be used in various combinations for the post-treatment of the lithographic printing plate precursor.
The printing plate obtained by the above treatment can be improved in printing durability by post-exposure treatment or heating treatment such as burning according to the method described in JP-A-2000-89478.
The planographic printing plate obtained by such processing is loaded on an offset printing machine and used for printing a large number of sheets.

  Hereinafter, although an example and a comparative example explain the present invention in detail, the present invention is not limited to these.

  1. Preparation of lithographic printing plate precursor

[Example 1]
(1) Production of support body An aluminum plate having a thickness of 0.3 mm was etched by being immersed in a 10% by mass aqueous sodium hydroxide solution at 60 ° C. for 25 seconds, washed with running water, and then neutralized and washed with a 20% by mass nitric acid aqueous solution. Then, it was washed with water. This was subjected to an electrolytic surface roughening treatment in a 1% by mass nitric acid aqueous solution using a sinusoidal alternating waveform current at an anode time electricity of 300 coulomb / dm ² . Subsequently, after dipping in a 1% by mass aqueous sodium hydroxide solution at 40 ° C. for 5 seconds and then in a 30% by mass sulfuric acid aqueous solution and desmutting at 60 ° C. for 40 seconds, the current density in a 20% by mass sulfuric acid aqueous solution was 2A / current density. Anodization was performed for 2 minutes so that the thickness of the anodized film was 2.7 g / m ² under the condition of dm ² . When the surface roughness was measured, it was 0.3 μm (Ra display according to JIS B0601).

The aluminum plate thus treated was first coated with the next intermediate layer solution using a bar coater and then dried at 80 ° C. for 20 seconds. A coating amount of the intermediate layer after drying was 10 mg / m ^2.

Intermediate layer solution ・ 100g of the following sol solution
・ Methanol 900g

Sol solution ・ Phosmer PE (Unichemical Co., Ltd.) 5g
・ Methanol 45g
・ Water 10g
・ 85% phosphoric acid 5g
・ Tetraethoxysilane 20g
・ 3-Methacryloxypropyltrimethoxysilane 15g

(2) Formation of photosensitive layer On the intermediate layer, a photopolymerizable composition P-1 having the following composition was applied so that the dry coating mass was 1.4 g / m ^2, and dried at 100 ° C. for 1 minute. A photosensitive layer was formed.

Photopolymerizable composition P-1
Polymerizable compound (1) 4.5 parts by mass Binder polymer (1) 5.3 parts by mass Sensitizing dye (1) 0.4 parts by mass Polymerization initiator (1) 0.9 parts by mass Chain transfer Agent (1) 0.5 part by mass-Dispersion of ε-phthalocyanine pigment 0.9 part by mass (Pigment: 15 parts by mass, dispersant (allyl methacrylate / methacrylic acid copolymer (copolymerization molar ratio 83/17)) : 10 parts by mass, cyclohexanone: 15 parts by mass)
・ Fluorine-based nonionic surfactant (Megafac F780 0.02 parts by mass (Dainippon Ink Chemical Co., Ltd.))
-Thermal polymerization inhibitor 0.03 parts by mass
(N-nitrosophenylhydroxylamine aluminum salt)
・ Methyl ethyl ketone 58 parts by mass ・ Propylene glycol monomethyl ether acetate 53 parts by mass

(3) Formation of protective layer A protective layer coating solution having the following composition was applied on the photosensitive layer so that the dry coating mass was 2.3 g / m ^2, and dried at 125 ° C. for 75 seconds. The lithographic printing plate precursor 1 was obtained.

Coating liquid for protective layer Polyvinyl alcohol (saponification degree 95 mol%, polymerization degree 500) 36 parts by weight Polyvinylpyrrolidone (molecular weight 50,000) 9 parts by weight Poly (vinylpyrrolidone / vinyl acetate (1/1)) molecular weight 70,000 0.5 Part by weight Surfactant (Emalex 710, manufactured by Nippon Emulsion Co., Ltd.) 0.5 part by weight Water 950 parts by weight

[Comparative Example 1]
A lithographic printing plate precursor A was obtained in the same manner as in Example 1 except that the binder polymer (1) of the photopolymerizable composition P-1 of Example 1 was changed to the following binder polymer (2).

[Example 2]
A lithographic printing plate precursor 2 was obtained in the same manner as in Example 1 except that the binder polymer (1) of the photopolymerizable composition P-1 of Example 1 was changed to the following binder polymer (3).

Example 3
A lithographic printing plate precursor 3 was obtained in the same manner as in Example 1 except that the binder polymer (1) of the photopolymerizable composition P-1 of Example 1 was changed to the following binder polymer (4).

[Examples 4 to 5]
A lithographic printing plate in the same manner as in Example 1 except that the sensitizing dye (1) of the photopolymerizable composition P-1 in Example 1 is changed to the following sensitizing dye (2) or (3), respectively. Original plates 4 to 5 were obtained.

[Examples 6 to 10]
A lithographic printing plate in the same manner as in Example 1 except that the chain transfer agent (1) of the photopolymerizable composition P-1 in Example 1 is changed to the following chain transfer agents (2) to (6), respectively. Original plates 6 to 10 were obtained.

Example 11
Except for changing the polymerization initiator (1) of the photopolymerizable composition P-1 of Example 1 to the following polymerization initiator (2) and further adding 0.3 parts by mass of the following sensitization aid (1). Produced a planographic printing plate precursor 11 in the same manner as in Example 1.

増感助剤（１）

Sensitization aid (1)

Example 12
A lithographic printing plate precursor 12 was obtained in the same manner as in Example 1 except that the support prepared as described below was used.
Preparation of support In order to remove rolling oil on the surface of an aluminum plate (material 1050) having a thickness of 0.3 mm, a degreasing treatment was performed at 50 ° C. for 30 seconds using a 10 mass% sodium aluminate aqueous solution, and the hair diameter was 0. The surface of the aluminum plate was grained using ^three .3 mm bundled nylon brushes and a pumice-water suspension (specific gravity 1.1 g / cm.sup.3) having a median diameter of 25 .mu.m and washed thoroughly with water. This plate was etched by being immersed in a 25 mass% sodium hydroxide aqueous solution at 45 ° C for 9 seconds, washed with water, further immersed in a 20 mass% nitric acid aqueous solution at 60 ° C for 20 seconds, and washed with water. The etching amount of the grained surface at this time was about 3 g / m ² .

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

Next, nitric acid electrolysis was performed with an aqueous solution of 0.5% by mass hydrochloric acid (containing 0.5% by mass of aluminum ions) and an electrolytic solution having a liquid temperature of 50 ° C. under the condition of an electric quantity of 50 C / dm ² when the aluminum plate was the anode. In the same manner as above, an electrochemical surface roughening treatment was performed, followed by washing with water by spraying. This plate was provided with a DC anodized film of 2.5 g / m ² at a current density of 15 A / dm ² using a 15 mass% sulfuric acid aqueous solution (containing 0.5 mass% of aluminum ions) as an electrolytic solution, then washed with water and dried. Further, it was treated with a 2.5% by mass aqueous solution of sodium silicate at 30 ° C. for 10 seconds. When the center line average roughness (Ra) of this aluminum plate was measured using a needle having a diameter of 2 μm, it was 0.51 μm.

Example 13
A lithographic printing plate precursor 13 was obtained in the same manner as in Example 12 except that the sensitizing dye (1) of the photopolymerizable composition P-1 of Example 12 was changed to the following sensitizing dye (4).

増感色素（４）

Sensitizing dye (4)

2. Evaluation of lithographic printing plate precursor (1) Printing durability The exposure amount on the lithographic printing plate precursor was 0.05 mJ / cm by using Vx9600CTP (light source wavelength: 405 nm) manufactured by Fuji Photo Film Co., Ltd. ^The image was adjusted to ² and drawn in an image. Thereafter, using a PS processor IP850HD manufactured by G & J Co., which was charged with an alkaline developer having the following composition, development was performed at a preheating temperature of 115 ° C./12 seconds, a developer temperature of 25 ° C., and a development time of 28 seconds. As the finisher, a 1: 3 water dilution of FN-6 manufactured by Fuji Photo Film Co., Ltd. was used.
The resulting lithographic printing plate was printed on a Lithrone printing machine manufactured by Komori Corporation, and DIC-GEOS (N) ink manufactured by Dainippon Ink & Chemicals, Ltd. as ink and Fuji Photo Film Co., Ltd. as dampening water. Printed using a mixture of etchant EU-3 / water / isopropyl alcohol = 1/89/10 (volume ratio), and the number of printed sheets at the time when it was visually recognized that the density of the solid image began to fade, The printability was evaluated.

(Alkali developer composition)
・ Potassium hydroxide 0.15g
・ Polyoxyethylene naphthyl ether (n = 13) 5.0 g
・ Chillest 400 (chelating agent) 0.1g
・ Water 94.75g

(2) Fine line reproducibility Printing was carried out as described above, and after 100 sheets were printed and it was confirmed that a printed matter having no ink stains in the non-image area was obtained, 4900 sheets were continuously printed. A fine line chart of the 5000th printed material (10, 12, 14, 16, 18, 20, 25, 30, 35, 40, 60, 80, 100 and 200 μm fine line exposed) with a 25X magnifier The fine line reproducibility was evaluated based on the fine line width that was observed and reproduced with ink without interruption.
The evaluation results are shown in Table 1 below.

  From the above results, it is clear that the lithographic printing plate precursor according to the invention is excellent in printing durability and fine line reproducibility.

Claims (8)

On the support, (A) a sensitizing dye represented by the following general formula (I) or (II), (B) a polymerization initiator, (C) a polymerizable compound, and (D) a binder having a crosslinkable group A lithographic printing plate precursor comprising a photosensitive layer containing a polymer.

Here, R < ¹ > -R < ¹⁴ > represents a hydrogen atom, an alkyl group, an alkoxy group, a cyano group, or a halogen atom each independently. However, at least one of R ^{1 to} R ¹⁰ represents an alkoxy group having 2 or more carbon atoms.
R ¹⁵ to R ³² each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a cyano group or a halogen atom. However, at least one of R ^{15 to} R ²⁴ represents an alkoxy group having 2 or more carbon atoms.   (D) The binder polymer having a crosslinkable group is a (meth) acrylic acid copolymer having a crosslinkable group in a side chain or a polyurethane resin having a crosslinkable group in a side chain. The lithographic printing plate precursor described.   The lithographic printing plate precursor as claimed in claim 1 or 2, further comprising a chain transfer agent (E) in the photosensitive layer. The lithographic printing plate precursor as claimed in claim 3, wherein the chain transfer agent (E) is a thiol compound represented by the following general formula (A).

Here, R represents an alkyl group which may have a substituent or an aryl group which may have a substituent, and A represents a 5-membered or 6-membered heterocyclic ring having a carbon atom together with an N = CN moiety. And A may further have a substituent.   (B) The lithographic printing plate precursor as claimed in any one of claims 1 to 4, wherein the polymerization initiator is a hexaarylbiimidazole compound or a metallocene compound.   The lithographic printing plate precursor as claimed in claim 1, further comprising a protective layer on the photosensitive layer.   The lithographic printing plate precursor according to any one of claims 1 to 6, wherein the lithographic printing plate precursor according to any one of claims 1 to 6 is image-exposed with a laser of 350 to 600 nm and then developed with a developer. Method.   The plate making method of a lithographic printing plate precursor according to claim 7, wherein the developer contains a nonionic surfactant having a polyoxyalkylene ether group.