JP2010049107A - Method for manufacturing lithographic printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a lithographic printing plate by which excellent treatment performance is secured in spite of one-liquid treatment and excellent inking property is also secured. <P>SOLUTION: The method for manufacturing a lithographic printing plate includes steps for image-exposing a lithographic printing plate precursor having a photosensitive layer containing (A) a sensitizing dye, (B) a polymerization initiator, (C) a polymerizable compound, (D) a binder polymer and (E) a specific compound on a support, and subjecting the exposed precursor to one-liquid treatment. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for preparing a lithographic printing plate.

In general, a lithographic printing plate comprises an oleophilic image area that receives ink in the printing process and a hydrophilic non-image area that receives dampening water. Lithographic printing uses the property that water and printing ink repel each other, so that the oleophilic image area of the lithographic printing plate is the ink receiving area and the hydrophilic non-image area is dampened with the water receiving area (ink non-receiving area). As described above, a difference in ink adhesion is caused on the surface of a lithographic printing plate, and after ink is applied only to an image portion, the ink is transferred to a printing medium such as paper and printed.
In order to produce this lithographic printing plate, a lithographic printing plate precursor (PS plate) in which an oleophilic photosensitive resin layer (photosensitive layer, image recording layer) is provided on a hydrophilic support has been widely used. Yes. Usually, the lithographic printing plate precursor is exposed through an original image such as a lithographic film, and then the portion that becomes the image portion of the image recording layer is left, and the other unnecessary image recording layer is removed with an alkaline developer or organic A lithographic printing plate is obtained by performing plate making by a method of dissolving and removing with a solvent and exposing a hydrophilic support surface to form a non-image portion.

  Thus, in the plate making process of the conventional lithographic printing plate precursor, after the exposure, a step of dissolving and removing unnecessary image recording layers with an alkaline developer or the like is necessary, but in terms of environment and safety, it is more neutral. Treatment with a near developer and a small amount of waste liquid are cited as problems. In particular, in recent years, disposal of waste liquid discharged with wet processing has become a major concern for the entire industry due to consideration for the global environment, and the demand for solving the above-mentioned problems has become stronger.

  On the other hand, in recent years, digitization technology for electronically processing, storing, and outputting image information by a computer has become widespread, and various new image output methods corresponding to such digitization technology will be put into practical use. It is becoming. Along with this, digitized image information is carried by high-convergence radiation such as laser light, and the lithographic printing plate precursor is scanned and exposed with that light, directly without using a lithographic film. Computer-to-plate (CTP) technology has been attracting attention. Accordingly, obtaining a lithographic printing plate precursor adapted to such a technique is one of the important technical issues.

  As mentioned above, the low alkali level of the developer and the simplification of the processing process are more strongly desired than ever in terms of consideration for the global environment, space saving, and low running cost. It has become to. However, as described above, the conventional development processing step consists of three steps of developing with an alkaline aqueous solution having a pH of 11 or more, then pouring an alkaline agent in a washing bath, and then processing with a gum solution mainly containing a hydrophilic resin. For this reason, the automatic developing machine itself takes up a large space, and there are still problems in terms of environment and running cost, such as a problem of developing waste liquid, washing waste liquid, and gum waste liquid.

On the other hand, for example, Patent Document 1 proposes a developing method in which processing is performed with a developer having an alkali metal carbonate and a bicarbonate having a pH of 8.5 to 11.5 and an electrical conductivity of 3 to 30 mS / cm. However, it requires water washing and a gum solution treatment process, and does not lead to solution of environmental and running cost problems.
Moreover, the Example of patent document 2 describes the process by the process liquid containing the water-soluble high molecular compound of pH 11.9-12. However, the printing plate obtained by this treatment is in a state in which the alkali of pH 12 remains attached to the plate surface, and there is a problem in terms of safety for the operator, and the time until printing after the printing plate preparation is long. As a result, the image portion gradually dissolves, leading to a decrease in the inking property.

As a method for ensuring the lipophilicity of the image recording layer, for example, a method using a polymer having a linear, branched or cyclic alkyl group having 4 to 20 carbon atoms such as phenolic hydroxyl group and stearyl group has been proposed ( For example, see Patent Document 3.) However, when the lipophilic polymer as described above is used as the main component of the binder, there is a problem that the effect on other performances such as developability becomes large because the addition amount is large. When a small amount of an oily polymer is used as an additive, there has been a problem that the effect of improving the ink depositability as expected cannot be obtained.
Further, as a method for ensuring the lipophilicity of the image recording layer, a method of containing a polymer compound having a fluoroaliphatic group has been proposed (see, for example, Patent Documents 4 and 5). However, a compound having a functional group containing a large number of fluorine atoms has properties such as oil repellency, water repellency, and alkali development resistance. There have been problems such as development debris depositing and sludge generation in the developing bath.
On the other hand, Patent Document 6 discloses a static friction coefficient between the surface of an image recording layer and the back surface of the support in order to suppress the generation of scratches and residual films on the image recording layer due to rubbing with the back surface of the support in the negative lithographic printing plate precursor. It has been proposed to add a compound having a long-chain aliphatic group such as behenic acid to the image recording layer for the purpose of controlling the content of the image recording layer to a specific range. However, since this negative lithographic printing plate precursor is subjected to plate making processing after image exposure and then through alkali development, water washing and gum processing steps, as described above, there are problems such as space saving, waste liquid processing, environment, and running cost. The point is not solved at all.
JP-A-11-65126 European Patent Application No. 1868036 JP 2004-117882 A JP 2002-311577 A JP 2004-101893 A JP 2002-296768 A

  Accordingly, it is an object of the present invention to provide a method for preparing a lithographic printing plate which is excellent in processability and excellent in inking properties despite the one-liquid treatment.

As a result of intensive studies, the present inventor has found that the object can be achieved by the following configuration, and has completed the present invention.
That is, the present invention is as follows.

(1) Photosensitive layer containing (A) sensitizing dye, (B) polymerization initiator, (C) polymerizable compound, (D) binder polymer, and (E) a compound represented by the following general formula (I) A method for preparing a lithographic printing plate, comprising subjecting a lithographic printing plate precursor having a slab to a support to one-liquid treatment after image exposure.
R ¹ —X Formula (I)
(In the formula, R ¹ represents a hydrocarbon group having 8 to 32 carbon atoms in total. X represents —CO—Y—R ² , —Y—CO—R ² , —NH—CO—Y—R ² , ^{-O-CO-NH-R 2} , -NH-CO-NH-R 2, -SO 2 -Y-R 2, -Y-SO 2 -R 2, -O-SO 2 -R 2, -CO- Represents O—CO—R ² or —Y—R ³ , wherein Y represents —O—, —S—, —NR ^4;
-Or a single bond. However, when X is —Y—R ³ , Y is not a single bond. R ² , R ³ and R ⁴ each represent a hydrogen atom or a hydrocarbon group having a total carbon number of 20 or less. )
(2) The method for preparing a lithographic printing plate as described in (1) above, wherein the lithographic printing plate precursor has a protective layer on the photosensitive layer.
(3) The method for preparing a lithographic printing plate as described in (2) above, wherein the protective layer contains acid-modified polyvinyl alcohol.
(4) The processing liquid in the one-liquid processing is an aqueous solution containing carbonate ions, hydrogen carbonate ions, a surfactant and / or a water-soluble polymer compound. A method for producing a lithographic printing plate according to any one of the above items.
(5) The above-described (1) to (1), wherein the treatment liquid in the one-liquid treatment is an aqueous solution containing a surfactant and / or a water-soluble polymer compound and having a pH of 8.5 to 10.8. The method for producing a lithographic printing plate according to any one of (3).
(6) The method for preparing a lithographic printing plate as described in any one of (1) to (5) above, wherein the (D) binder polymer has an acid group in a side chain.
(7) The method for producing a lithographic printing plate as described in (6) above, wherein the acid group is a carboxylic acid group.

  The method for producing a lithographic printing plate according to the present invention can provide a lithographic printing plate having excellent processability and good inking properties. Furthermore, since one-component development is possible with a weak alkaline processing solution, there are advantages such as simplification of processing steps, consideration for the global environment, space saving, and low running cost.

[Lithographic printing plate precursor]
First, the lithographic printing plate precursor used in the lithographic printing plate preparation method of the present invention will be described. The lithographic printing plate precursor has a photosensitive layer on a support.

<Photosensitive layer>
The photosensitive layer in the lithographic printing plate precursor according to the invention is represented by (A) a sensitizing dye, (B) a polymerization initiator, (C) a polymerizable compound, (D) a binder polymer, and (E) a general formula (I). Containing the compound. Hereinafter, the components of the photosensitive layer will be described in detail.

(A) Sensitizing dye For example, a sensitizing dye having a maximum absorption at 350 to 450 nm and an infrared absorber having a maximum absorption at 750 to 1400 nm are added to the photosensitive layer. It is possible to provide a highly sensitive lithographic printing plate precursor corresponding to the 405 nm violet laser, 532 nm green laser, and 803 nm IR laser.
First, a sensitizing dye having a maximum absorption in the wavelength region of 350 to 450 nm will be described. Examples of such a sensitizing dye include merocyanine dyes, benzopyrans, coumarins, aromatic ketones, anthracenes, and the like.

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

In the general formula (IV), A represents an aromatic ring group or a heterocyclic group which may have a substituent, and X represents an oxygen atom, a sulfur atom or N- (R ₃ ). R ₁ , R ₂ and R ₃ each independently represents a monovalent non-metallic atomic group, A and R _1, and R ₂ and R ₃ are bonded to each other;
An aliphatic or aromatic ring may be formed.

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

A in the general formula (IV) represents an aromatic ring group or a heterocyclic group which may have a substituent, and the aromatic ring or heterocyclic ring which may have a substituent in the general formula (IV) And the same as the substituted or unsubstituted aryl group and the substituted or unsubstituted aromatic heterocyclic residue described in R ₁ , R ₂ and R ₃ .

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

  Furthermore, a sensitizing dye represented by any one of the following general formulas (V) to (VII) can also be used.

In formula (V), R ^{1 to} R ¹⁴ each independently represents a hydrogen atom, an alkyl group, an alkoxy group, a cyano group or a halogen atom. However, at least one of R ^{1 to} R ¹⁰ represents an alkoxy group having 2 or more carbon atoms.
In the formula (VI), R ^{15 to} R ³² each independently represents 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.

In formula (VII), R ¹ , R ² and R ³ each independently represents a halogen atom, an alkyl group, an aryl group, an aralkyl group, an —NR ⁴ R ⁵ group or an —OR ⁶ group, and R ⁴ , R ⁵ And R ⁶ each independently represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, and k, m and n each represents an integer of 0 to 5.

In addition, JP 2007-171406 A, JP 2007-206216 A, JP 2007-206217 A, JP 2007-225701 A, JP 2007-225702 A, JP 2007-316582 A, Sensitizing dyes described in JP-A-2007-328243 can also be preferably used.
The preferable addition amount of the sensitizing dye having an absorption maximum in the wavelength range of 350 nm to 450 nm is preferably 0.05 to 30 parts by mass, more preferably 0.1 to 20 parts per 100 parts by mass of the total solid content of the photosensitive layer. It is in the range of 0.2 to 10 parts by weight, most preferably 0.2 to 10 parts by weight.

Subsequently, a sensitizing dye having a maximum absorption in a wavelength range of 750 to 1400 nm that is preferably used in the present invention will be described in detail.
Such a sensitizing dye includes an infrared absorber, and is highly sensitive to infrared laser irradiation (exposure) and is in an electronically excited state. Electron transfer, energy transfer, and heat generation (photothermal conversion function) associated with the electronically excited state. It is estimated that these act on the polymerization initiator coexisting in the photosensitive layer to cause a chemical change in the polymerization initiator to generate radicals. In any case, the addition of a sensitizing dye having a maximum absorption at 750 to 1400 nm is particularly suitable for plate making directly drawn with an infrared laser beam having a wavelength of 750 to 1400 nm, and the conventional lithographic printing plate precursor Compared with this, high image forming properties can be exhibited.

  The infrared absorber is preferably a dye or pigment having an absorption maximum in a wavelength region of 750 nm to 1400 nm.

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

In formula (a), X ¹ represents a hydrogen atom, a halogen atom, -NPh ^_2, -X ₂ -L ¹ or a group shown below. Here, X ² represents an oxygen atom, a nitrogen atom, or a sulfur atom, and L ¹ represents a hydrocarbon group having 1 to 12 carbon atoms, an aromatic ring having a hetero atom, or 1 to 1 carbon atom containing a hetero atom. 12 hydrocarbon groups are shown. In addition, a hetero atom here shows N, S, O, a halogen atom, and Se. X _a ^- is Z _a which will be described below ^- has the same definition as, R ^a represents a hydrogen atom, an alkyl group, an aryl group, a substituted or unsubstituted amino group, substituted or unsubstituted amino group and a halogen atom.

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

Ar ¹ and Ar ² may be the same or different and each represents an aromatic hydrocarbon group which may have a substituent. Preferred aromatic hydrocarbon groups include a benzene ring and a naphthalene ring. Moreover, as a preferable substituent, a C12 or less hydrocarbon group, a halogen atom, and a C12 or less alkoxy group are mentioned. Y ¹ and Y ² may be the same or different and each represents a sulfur atom or a dialkylmethylene group having 12 or less carbon atoms. R ³ and R ⁴ may be the same or different and each represents a hydrocarbon group having 20 or less carbon atoms which may have a substituent. Preferred substituents include alkoxy groups having 12 or less carbon atoms, carboxyl groups, and sulfo groups. R ⁵ , R ⁶ , R ⁷ and R ⁸ may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 12 or less carbon atoms. From the availability of raw materials, a hydrogen atom is preferred. Za ⁻ represents a counter anion. However, when the cyanine dye represented by formula (a) has an anionic substituent in its structure and does not require charge neutralization, Za ^- is not necessary. Preferred Za ⁻ is a halogen ion, a perchlorate ion, a tetrafluoroborate ion, a hexafluorophosphate ion, and a sulfonate ion, particularly preferably a perchlorate ion, a hexagonal salt, in view of storage stability of the photosensitive layer coating solution. Fluorophosphate ions and aryl sulfonate ions. In addition, the thing which does not contain a halogen ion as a counter ion is especially preferable.

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

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

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

  The particle size of the pigment is preferably in the range of 0.01 μm to 10 μm, more preferably in the range of 0.05 μm to 1 μm, and particularly preferably in the range of 0.1 μm to 1 μm. Within this preferred particle size range, excellent dispersion stability of the pigment in the photosensitive layer can be obtained, and a uniform photosensitive layer can be obtained.

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

  The infrared absorber may be added to the same layer as other components, or another layer may be provided and added thereto.

  From the viewpoint of uniformity in the photosensitive layer and durability of the photosensitive layer, the infrared absorbent is 0.01 to 50% by mass, preferably 0.1 to 10% by mass, based on the total solid content constituting the photosensitive layer. In the case of, it is particularly preferably 0.5 to 10% by mass, and in the case of a pigment, particularly preferably 0.1 to 10% by mass.

(B) Polymerization initiator
The photosensitive layer of the present invention contains a polymerization initiator (hereinafter also referred to as an initiator compound). The initiator compound is a compound that undergoes a chemical change through the action of electron transfer, energy transfer, heat generation, etc. caused by the electronic excitation state of the sensitizing dye, and generates at least one selected from radicals, acids, and bases. is there. Hereinafter, radicals, acids, and bases generated in this way are simply referred to as active species. When the initiator compound is not present or when only the initiator compound is used alone, practically sufficient sensitivity cannot be obtained. As one mode in which a sensitizing dye and an initiator compound are used in combination, they can be used as a single compound by an appropriate chemical method (such as linking a sensitizing dye and an initiator compound through a chemical bond). It is.

  Usually, many of these initiator compounds are considered to generate active species through the initial chemical processes represented by the following (1) to (3). (1) Reductive decomposition of the initiator compound based on the electron transfer reaction from the electronically excited state of the sensitizing dye to the initiator compound, (2) Electron transfer from the initiator compound to the electronically excited state of the sensitizing dye (3) decomposition of the initiator compound from the electronically excited state based on energy transfer from the electronically excited state of the sensitizing dye to the initiator compound. In many cases, it is ambiguous as to which type (1) to (3) each individual initiator compound belongs, but in the present invention, a very high increase can be achieved by combining any of these types of initiator compounds. A feeling effect is obtained.

  As the initiator compound in the present invention, those known among those skilled in the art can be used without limitation. Specifically, for example, trihalomethyl compounds, carbonyl compounds, organic peroxides, azo compounds, azide compounds, metallocene compounds can be used. , Hexaarylbiimidazole compounds, organic boron compounds, disulfone compounds, oxime ester compounds, onium salt compounds, and iron arene complexes. 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. Two or more polymerization initiators may be used in combination as appropriate.

Examples of hexaarylbiimidazole compounds include lophine dimers described in JP-B-45-37377 and JP-B-44-86516, such as 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 ' − Traphenylbiimidazole, 2,2'-bis (o-methylphenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (o-trifluoromethylphenyl) -4, Examples include 4 ', 5,5'-tetraphenylbiimidazole.
The hexaarylbiimidazole compound is particularly preferably used in combination with a sensitizing dye having a maximum absorption at 350 to 450 nm.

  The onium salt suitably used in the present invention (in the present invention, functions as an ionic polymerization initiator, not as an acid generator) is represented by the following general formulas (RI-I) to (RI-III). Onium salt.

In the formula (RI-I), Ar ₁₁ represents an aryl group having 20 or less carbon atoms which may have 1 to 6 substituents, and preferred substituents include an alkyl group having 1 to 12 carbon atoms and a carbon number. C2-C12 alkenyl group, C2-C12 alkynyl group, C6-C12 aryl group, C1-C12 alkoxy group, C6-C12 aryloxy group, halogen atom, C1-C1 12 alkylamino groups, C2-C12 dialkylamino groups, C1-C12 alkylamide groups or arylamide groups, carbonyl groups, carboxyl groups, cyano groups, sulfonyl groups, C1-C12 thioalkyl groups And a thioaryl group having 6 to 12 carbon atoms. Z ₁₁ ^- represents a monovalent anion, specifically a halogen ion, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, sulfonate ion, sulfinate ion, thiosulfonate ion, a sulfate ion Can be mentioned. Of these, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, sulfonate ion and sulfinate ion are preferable from the viewpoint of stability.

In the formula (RI-II), Ar ₂₁ and Ar ₂₂ each independently represent an aryl group having 20 or less carbon atoms which may have 1 to 6 substituents, and preferred substituents include 1 to 1 carbon atoms. 12 alkyl groups, alkenyl groups having 2 to 12 carbon atoms, alkynyl groups having 2 to 12 carbon atoms, aryl groups having 6 to 12 carbon atoms, alkoxy groups having 1 to 12 carbon atoms, aryloxy groups having 6 to 12 carbon atoms, Halogen atom, C1-C12 alkylamino group, C2-C12 dialkylamino group, C1-C12 alkylamide group or arylamide group, carbonyl group, carboxyl group, cyano group, sulfonyl group, carbon Examples thereof include a thioalkyl group having 1 to 12 carbon atoms and a thioaryl group having 6 to 12 carbon atoms. Z ₂₁ ⁻ represents a monovalent anion. Specific examples include halogen ions, perchlorate ions, hexafluorophosphate ions, tetrafluoroborate ions, sulfonate ions, sulfinate ions, thiosulfonate ions, sulfate ions, and carboxylate ions. Among these, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, sulfonate ion, sulfinate ion, and carboxylate ion are preferable from the viewpoint of stability and reactivity.

In the formula (RI-III), R ₃₁ , R ₃₂ and R ₃₃ are each independently an aryl group, alkyl group, alkenyl group or alkynyl having 20 or less carbon atoms, which may have 1 to 6 substituents. Represents a group. Among them, an aryl group is preferable from the viewpoint of reactivity and stability. Examples of the substituent include an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, an alkynyl group having 2 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, Aryloxy group having 6 to 12 carbon atoms, halogen atom, alkylamino group having 1 to 12 carbon atoms, dialkylamino group having 2 to 12 carbon atoms, alkylamide group or arylamide group having 1 to 12 carbon atoms, carbonyl group, carboxyl Group, a cyano group, a sulfonyl group, a thioalkyl group having 1 to 12 carbon atoms, and a thioaryl group having 6 to 12 carbon atoms. Z ₃₁ ^- represents a monovalent anion. Specific examples include halogen ions, perchlorate ions, hexafluorophosphate ions, tetrafluoroborate ions, sulfonate ions, sulfinate ions, thiosulfonate ions, sulfate ions, and carboxylate ions. Of these, perchlorate ion, hexafluorophosphate ion, tetrafluoroborate ion, sulfonate ion, sulfinate ion, and carboxylate ion are preferable from the viewpoints of stability and reactivity. More preferred are the carboxylate ions described in JP-A No. 2001-343742, and particularly preferred are the carboxylate ions described in JP-A No. 2002-148790.
The onium salt is particularly preferably used in combination with an infrared absorber having a maximum absorption at 750 to 1400 nm.

  In addition, JP 2007-171406 A, JP 2007-206216 A, JP 2007-206217 A, JP 2007-225701 A, JP 2007-225702 A, JP 2007-316582 A, A polymerization initiator described in JP-A-2007-328243 can be preferably used.

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 can be used without any particular limitation in the present invention. The polymerizable compound has a chemical form such as a monomer, a prepolymer, that is, a dimer, a trimer and an oligomer, or a copolymer thereof and a mixture thereof. Examples of the polymerizable compound include compounds represented by the following general formulas (1) to (5).

In general formula (1), R _{1 to} R ₃ each independently represents a monovalent organic group. R ₁ preferably includes a hydrogen atom or an alkyl group, and among them, a hydrogen atom and a methyl group are preferable because of high radical reactivity. R _{2 and} R ₃ are each independently hydrogen atom, halogen atom, amino group, carboxyl group, alkoxycarbonyl group, sulfo group, nitro group, cyano group, alkyl group, aryl group, alkoxy group, aryloxy Group, alkylamino group, arylamino group, alkylsulfonyl group, arylsulfonyl group, and the like. Among them, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, an alkyl group, and an aryl group are preferable because of high radical reactivity.

X represents an oxygen atom, a sulfur atom, —N (R ₁₂ ) — or —C (R ₁₂ R ₁₃ ) —, and R ₁₂ or R ₁₃ represents a monovalent organic group. Here, examples of the monovalent organic group represented by R ₁₂ or R ₁₃ include an alkyl group. R ₁₂ or R ₁₃ is preferably a hydrogen atom, a methyl group, an ethyl group or an isopropyl group because of high radical reactivity. R ₁₂ or R ₁₃ may combine with the atoms constituting L to form a ring.

  The organic group may have a substituent as long as it can be introduced. 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, Examples thereof include 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, and an arylsulfonyl group.

  L is hydrogen, fluorine, chlorine, bromine, iodine, carbon, nitrogen, oxygen, boron, sulfur, phosphorus, silicon, lithium, sodium, potassium, magnesium, calcium, aluminum, scandium, titanium, vanadium, chromium, manganese, iron N-valent organic residue composed of cobalt, nickel, zinc, gallium, germanium, silver, palladium, lead, zirconium, rhodium, tin, platinum, tungsten, hydrogen, fluorine, chlorine, bromine, iodine, carbon , Preferably an n-valent organic residue composed of nitrogen, oxygen, boron, sulfur, phosphorus, silicon, lithium, sodium, potassium, magnesium, calcium, hydrogen, fluorine, chlorine, bromine, iodine, carbon, It is more preferably an n-valent organic residue composed of nitrogen, oxygen, boron, sulfur, phosphorus, and silicon.

  n represents a natural number, preferably from 1 to 100, more preferably from 2 to 80, and still more preferably from 3 to 60.

  Specific examples of the polymerizable compound represented by the general formula (1) include (a) unsaturated carboxylic acid (for example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, 2-hydroxymethylacrylic acid, α-bromoacrylic acid, fumaric acid, mesaconic acid, maleic acid, etc.), (b) esters thereof, (c) amides thereof, preferably (d) unsaturated carboxylic acid and aliphatic polyvalent Esters with alcohol compounds and (f) amides of unsaturated carboxylic acids and aliphatic polyvalent amine compounds are used. And (g) 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 a monofunctional Alternatively, a dehydration condensation reaction product with a polyfunctional carboxylic acid is also preferably used. (H) an addition reaction product of an unsaturated carboxylic acid ester or amide having an electrophilic substituent such as an isocyanate group or an epoxy group with a monofunctional or polyfunctional alcohol, amine or thiol; i) A substitution reaction product of an unsaturated carboxylic acid ester or amide having a leaving substituent such as a halogen group or a tosyloxy group with a monofunctional or polyfunctional alcohol, amine or thiol is also suitable. Moreover, it is also possible to use the compound group replaced with unsaturated ketone (for example, vinyl methyl ketone, vinyl ethyl ketone, etc.) 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, for example, 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 Japanese Patent No. 5241 and JP-A-2-226149, those containing an amino group described in JP-A-1-165613, and the like are also preferably used.
The aforementioned ester monomers 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, and specific examples thereof include, for example, 2 molecules per molecule described in JP-B-48-41708. A vinyl urethane compound containing two or more polymerizable vinyl groups in one molecule obtained by adding a vinyl monomer containing a hydroxyl group represented by the following general formula (A) to a polyisocyanate compound having one or more isocyanate groups Is mentioned.

_{CH 2 = C (R 4)} COOCH 2 CH (R 5) OH (A)
(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 JP 17654, JP-B 62-39417, and JP-B 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. Mention may be made of polyfunctional acrylates and methacrylates such as reacted epoxy acrylates. Further, specific unsaturated compounds described in JP-B-46-43946, JP-B-1-40337, JP-B-1-40336, and vinylphosphonic acid compounds described in JP-A-2-25493 Etc. can also be mentioned. In some cases, a structure containing a perfluoroalkyl group described in JP-A-61-22048 is preferably used. Furthermore, Journal of Japan Adhesion Association vol. 20, no. 7, 300-308 pages (1984) can also be used photocurable monomers and oligomers.

In General formula (2), R < ₁ > -R < ₅ > represents a monovalent organic group each independently. R _{1 to} R ₅ are preferably hydrogen atom, halogen atom, amino group, dialkylamino group, carboxyl group, alkoxycarbonyl group, sulfo group, nitro group, cyano group, alkyl group, aryl group, alkoxy group, aryl Examples thereof include an oxy group, an alkylamino group, an arylamino group, an alkylsulfonyl group, and an arylsulfonyl group, and among them, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, an alkyl group, and an aryl group are more preferable. R _{1 to} R ₅ may form a ring with any two, or may be linked to the atoms constituting L to form a ring.

The organic group may have a substituent as long as it can be introduced, and 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, —N (R ₁₂ ) — or —C (R ₁₂ R ₁₃ ) —. R _12, R ₁₃ has the same meaning as R _12, R ₁₃ in the general formula (1), and preferred examples are also the same.

  L and n are synonymous with L and n in the general formula (1), and preferred examples are also the same.

  Specific examples of the polymerizable compound represented by the general formula (2) include alcohols having an unsaturated double bond (for example, allyl alcohol, ethylene glycol monoallyl ether, 2-methyl-2-propen-1-ol, 3-buten-1-ol, 3-buten-2-ol, 2-methyl-3-buten-2-ol, 4-penten-1-ol, 2-cyclohexen-1-ol, retinol, etc.) and monofunctional Or polyfunctional carboxylic acid (acetic acid, benzoic acid, acetylsalicylic acid, succinic acid, maleic acid, tricarbaric acid, tartaric acid, citric acid, 1,3,5-cyclohexanetricarboxylic acid, phthalic acid, 1,2,4-benzenetricarboxylic acid Acid ester compounds, alcohols with unsaturated double bonds, and mono- or polyfunctional iso (thio) cyanates (butyl isocyanate, 1,4-diisocyanatobutane, 1,3-bis (sisocyanatomethyl) Chlorohexane, 4,4'-methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, ethyl isocyanatoacetate, allyl isothiocyanate, phenyl isothiocyanate, phenyl isocyanate, 2-chlorophenyl isocyanate, 3-methoxyphenyl isocyanate, methyl 2-isocyanatobenzoate, Urethane compounds such as 3-cyanophenyl isocyanate, 1-naphthyl isocyanate, 4,4′-methylenebis (phenylisocyanate), 4,4′-oxybis (phenylisocyanate), monofunctional or alcohol having an unsaturated double bond Polyfunctional alcohols (ethanol, isopropyl alcohol, ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, cyclohexanediol, Nositol, glycerol, 1,1,1-tris (hydroxymethyl) ethane, trimethylolpropane, triethanolamine, pentaerythritol, xylitol, L-mannose, D-glucose, dextrin, hydroxyethyl acrylate, diethylbis (hydroxyethyl) malonate 1,3,5-tris (2-hydroxyethyl) cyanuric acid, phenol, cresol, catechol, 1,5-dihydroxynaphthalene, bisphenol A, etc.) ether compounds, alcohols with unsaturated double bonds and monofunctional or Polyfunctional epoxy compounds (ethylene glycol diglycidyl ether, glycidyl methacrylate, cyclohexene oxide, neopentyl glycol diglycidyl ether, 1,3,5-cyclohexanetricarboxylic acid triglycidyl ester, Addition reaction product of ris (2,3-epoxypropyl) isocyanurate, etc., alcohol having unsaturated double bond and monofunctional or polyfunctional alkyl halide (1,4-dibromobutane, 1-iodooctane, maleic acid) Bis (2-bromoethyl) ester) or monofunctional or polyfunctional alcohol sulfonic acid (methanesulfonic acid, ethanesulfonic acid, camphorsulfonic acid, benzenesulfonic acid, toluenesulfonic acid, etc.) ester substitution reaction product, Alkyl halides with heavy bonds (eg, allyl bromide, 4-bromo-1-butene, 3-chloro-2-methylpropene, etc.) and sulfonate esters of alcohols with unsaturated double bonds and monofunctional or polyfunctional Alcohol, monofunctional or polyfunctional amine (for example, butylamine, ethylenediamine, triethylamine, Lumidine, pentaethylenehexamine, 1,2-diaminocyclohexane, 2,2'-oxybis (ethylamine), morpholine, 4,4'-trimethylenedipiperidine, piperazine, pyridine, glycine, proline, 4,4'-methylenedi Aniline, etc.), monofunctional or polyfunctional phosphine (eg, triphenylphosphine, tricyclohexylphosphine, etc.), monofunctional or polyfunctional thiol (eg, dodecyl mercaptan, pentaerythritol tetrakis (3-mercaptopropionic acid), dipentaerythritol hexa Nucleophiles such as kiss (2-mercaptoacetic acid), monofunctional or polyfunctional carbonyl compounds (eg acetone, diethyl malonate, t-butyl acetoacetate, ethyl phenylacetate), monofunctional or polyfunctional carboxylates Substitution reaction product An amine having a sum double bond (eg, allylamine, diallylamine, triallylamine, geranylamine, N-ethyl-2-methylallylamine, etc.), an amide of a monofunctional or polyfunctional carboxylic acid, an amine having an unsaturated double bond Monofunctional or polyfunctional isocyanate urea, unsaturated double bond amine and monofunctional or polyfunctional alkyl halide or monofunctional or polyfunctional alcohol sulfonate substitution reaction product, unsaturated double bond amine And imines of monofunctional or polyfunctional carbonyl compounds (eg acetone, 2,3-butanedione, 1,4-cyclohexanedione, terephthalaldehyde, etc.), amines with unsaturated double bonds and monofunctional or polyfunctional sulfonic acids ( For example, toluene sulfonic acid, methane sulfonic acid, 1,5-naphthalenedisulfonic acid 1,3,5-naphthalene trisulfonic acid, etc.) sulfonamides, iso (thio) cyanates with unsaturated double bonds (eg allyl isocyanate, allyl isothiocyanate, etc.) and urethanes of monofunctional or polyfunctional alcohols, Iso (thio) cyanate having unsaturated double bond and urea of monofunctional or polyfunctional amine, iso (thio) cyanate having unsaturated double bond and amide of monofunctional or polyfunctional carboxylic acid, unsaturated double bond An addition reaction product of an iso (thio) cyanate having a monofunctional or polyfunctional thiol and an addition reaction product of an iso (thio) cyanate having an unsaturated double bond and a monofunctional or polyfunctional iso (thio) cyanate .

In Formula (3), R _{1 to} R ₃ each independently represents a monovalent organic group. R _{1 to} R ₃ are preferably hydrogen atom, halogen atom, amino group, dialkylamino group, carboxyl group, alkoxycarbonyl group, sulfo group, nitro group, cyano group, alkyl group, aryl group, alkoxy group, aryl Examples thereof include an oxy group, an alkylamino group, an arylamino group, an alkylsulfonyl group, and an arylsulfonyl group, and among them, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, an alkyl group, and an aryl group are more preferable. R _{1 to} R ₅ may form a ring with any two, or may be linked to the atoms constituting L to form a ring.

The organic group may have a substituent as long as it can be introduced, and 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 ₁₂₎ - or -C (R ₁₂ R ₁₃₎ - represents a. R _12, R ₁₃ has the same meaning as R _12, R ₁₃ in the general formula (1), and preferred examples are also the same.

  L and n are synonymous with L and n in the general formula (1), and preferred examples are also the same.

  Specific examples of the polymerizable compound represented by the general formula (3) include monofunctional or polyfunctional carboxylic acid vinyl esters such as vinyl acetate, isopropenyl acetate, trivinyl 1,3,5-cyclohexanetricarboxylate, 1,4 -Vinyl ethers such as cyclohexanedimethanol divinyl ether and trimethylolpropane trivinyl ether, vinyl ether alcohols such as ethylene glycol monovinyl ether and diethylene glycol monovinyl ether and monofunctional or polyfunctional carboxylic acid esters, vinyl ethers such as ethylene glycol monovinyl ether and diethylene glycol monovinyl ether Alcohol and monofunctional or polyfunctional iso (thio) cyanate urethane, ethylene glycol monovinyl ether, diethylene glycol monovinyl ether Substitution products of vinyl ether alcohols such as water and monofunctional or polyfunctional alkyl halides or sulfonic acid esters of monofunctional or polyfunctional alcohols, vinyl ether alcohols such as ethylene glycol monovinyl ether, diethylene glycol monovinyl ether and monofunctional or polyfunctional epoxy Addition products, vinyl ether alkyl halides such as 2-chloroethyl vinyl ether, vinyl ether sulfonate esters such as p-toluenesulfonic acid vinyloxyethyl ester and monofunctional or polyfunctional alcohols, monofunctional or polyfunctional amines, monofunctional or polyfunctional Substitution reaction product of nucleophilic compound such as functional phosphine, monofunctional or polyfunctional thiol, monofunctional or polyfunctional carbonyl compound, monofunctional or polyfunctional carboxylate, 3-amino-1-propanol Nyl ether, vinyl ether amine such as 2- (diethylamino) ethanol vinyl ether and monofunctional or polyfunctional carboxylic acid amide, 3-amino-1-propanol vinyl ether, vinyl ether amine such as 2- (diethylamino) ethanol vinyl ether and monofunctional or polyfunctional Iso (thio) cyanate urea, 3-amino-1-propanol vinyl ether, substitution products of vinyl ether amines such as 2- (diethylamino) ethanol vinyl ether and monofunctional or polyfunctional alkyl halides, 3-amino-1-propanol vinyl ether , Monofunctional or polyfunctional vinyl ethers, such as sulfonamides of monofunctional or polyfunctional sulfonic acids, vinyl ether amines such as 2- (diethylamino) ethanol vinyl ether, N-vinyl rubazole, N-vinyl pyrrole Non monofunctional or polyfunctional vinyl amide, such as N- vinyl phthalimide, and the like.

In General formula (4), R < ₁ > -R < ₃ > represents a monovalent organic group each independently. R _{1 to} R ₃ are preferably hydrogen atom, halogen atom, amino group, dialkylamino group, carboxyl group, alkoxycarbonyl group, sulfo group, nitro group, cyano group, alkyl group, aryl group, alkoxy group, aryl Examples thereof include an oxy group, an alkylamino group, an arylamino group, an alkylsulfonyl group, and an arylsulfonyl group, and among them, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, an alkyl group, and an aryl group are more preferable. R _{4 to} R ₈ each independently represents a monovalent organic group or a divalent organic group linked to L. As the monovalent organic group, the above-described organic groups are preferable, and the divalent organic group is a divalent organic group composed of hydrogen, carbon, oxygen, nitrogen, sulfur, halogen, silicon, and phosphorus. Is preferred. Further, any two of R _{4 to} R ₈ may form a ring, or may be connected to an atom constituting L to form a ring.

  The organic group may have a substituent as long as it can be introduced, and examples of the substituent that can be introduced are the same as those in the general formula (1).

  L and n are synonymous with L and n in the general formula (1), and preferred examples are also the same.

Specific examples of the polymerizable compound represented by the general formula (4) include carboxylic acid group-containing styrene such as p-styrene carboxylic acid and sulfonic acid group-containing styrene such as p-styrene sulfonic acid and monofunctional or polyfunctional alcohol. Esters of carboxylic acid groups such as p-styrene carboxylic acid and amides of sulfonic acid group-containing styrene such as p-styrene sulfonic acid and monofunctional or polyfunctional amines, p-hydroxymethyl styrene and p-styrene carboxylic acid 2 -Hydroxyl-containing styrene and monofunctional or polyfunctional carboxylic acid esters such as hydroxyethyl ester and p-styrenesulfonic acid 2-hydroxyethyl ester, p-hydroxymethylstyrene and p-styrenecarboxylic acid 2-hydroxyethyl ester and p- Monofunctional with hydroxyl group-containing styrene such as styrenesulfonic acid 2-hydroxyethyl ester Or urethane of polyfunctional iso (thio) cyanate, hydroxyl group-containing styrene such as p-hydroxymethylstyrene, p-styrenecarboxylic acid 2-hydroxyethyl ester and p-styrenesulfonic acid 2-hydroxyethyl ester, and monofunctional or polyfunctional halogen Substituted products of sulfonates of alkyl halides and monofunctional or polyfunctional alcohols, hydroxyl group-containing styrenes such as p-hydroxymethylstyrene, p-styrenecarboxylic acid 2-hydroxyethyl ester and p-styrenesulfonic acid 2-hydroxyethyl ester And monofunctional or polyfunctional epoxy addition products, halogenated alkyl groups such as p-chloromethylstyrene and p-styrenecarboxylic acid 2-chloroethyl ester, and sulfonic acid ester groups such as p-tosyloxymethylstyrene Styrene and monofunctional or polyfunctional polymers A substitution reaction product of a nucleophilic compound such as alcohol, monofunctional or polyfunctional amine, monofunctional or polyfunctional phosphine, monofunctional or polyfunctional thiol, monofunctional or polyfunctional carbonyl compound, monofunctional or polyfunctional carboxylate, Amino group-containing styrene such as p-aminomethylstyrene and monofunctional or polyfunctional carboxylic acid amide, p-aminomethylstyrene or other amino group-containing styrene and monofunctional or polyfunctional iso (thio) cyanate urea, p-amino Examples thereof include substitution products of amino group-containing styrene such as methylstyrene and monofunctional or polyfunctional alkyl halides, and amino group-containing styrene such as p-aminomethylstyrene and sulfonamide of monofunctional or polyfunctional sulfonic acid.

In General formula (5), R < ₁ > -R < ₃ > represents a monovalent organic group each independently. R _{1 to} R ₃ are preferably hydrogen atom, halogen atom, amino group, dialkylamino group, carboxyl group, alkoxycarbonyl group, sulfo group, nitro group, cyano group, alkyl group, aryl group, alkoxy group, aryl Examples thereof include an oxy group, an alkylamino group, an arylamino group, an alkylsulfonyl group, and an arylsulfonyl group, and among them, a hydrogen atom, a carboxyl group, an alkoxycarbonyl group, an alkyl group, and an aryl group are more preferable. R ₅ represents a monovalent organic group. As the monovalent organic group, the aforementioned monovalent organic group is preferable. R ₅ may form a ring with L.

The organic group may have a substituent as long as it can be introduced, and examples of the substituent that can be introduced are the same as those in the general formula (1). Further, W is an oxygen atom, a sulfur atom, -N (R ₁₂₎ -, or -C (R ₁₂ R ₁₃₎ - represents a. R _12, R ₁₃ has the same meaning as R _12, R ₁₃ in the general formula (1), and preferred examples are also the same.

  L and n are synonymous with L and n in the general formula (1), and preferred examples are also the same.

  Specific examples of the polymerizable compound represented by the general formula (5) include vinylphosphonic acid and ester of monofunctional or polyfunctional alcohol such as vinylphosphonic acid and methyl 2-phosphonoacrylate, and amide of monofunctional or polyfunctional amine. , Bis (2-hydroxyethyl) vinylphosphonic acid p-hydroxymethylstyrene, p-styrenecarboxylic acid 2-hydroxyethyl ester, p-styrenesulfonic acid 2-hydroxyethyl ester, and other hydroxyl group-containing styrene and monofunctional or polyfunctional carboxylic acid Esters of acids, urethanes of hydroxyl-containing styrene and monofunctional or polyfunctional iso (thio) cyanates such as p-hydroxymethylstyrene, p-styrenecarboxylic acid 2-hydroxyethyl ester and p-styrenesulfonic acid 2-hydroxyethyl ester, p-Hydroxymethyl styrene or p-styrene carboxylic acid 2-H Substitution products of hydroxyl group-containing styrene such as loxyethyl ester and p-styrenesulfonic acid 2-hydroxyethyl ester with monofunctional or polyfunctional alkyl halides and sulfonic acid esters of monofunctional or polyfunctional alcohols, p-hydroxymethylstyrene, Addition products of hydroxyl-containing styrene and monofunctional or polyfunctional epoxy such as p-styrenecarboxylic acid 2-hydroxyethyl ester and p-styrenesulfonic acid 2-hydroxyethyl ester, p-chloromethylstyrene and p-styrenecarboxylic acid 2 Sulfuric acid ester group-containing styrene such as -chloroethyl ester and sulfonic acid ester group styrene such as p-tosyloxymethylstyrene, monofunctional or polyfunctional alcohol, monofunctional or polyfunctional amine, monofunctional or polyfunctional phosphine, Functional or polyfunctional thiol, simple Functional or polyfunctional carbonyl compounds, substitution reaction products of nucleophilic compounds such as monofunctional or polyfunctional carboxylates, amino group-containing styrene such as p-aminomethylstyrene and amides of monofunctional or polyfunctional carboxylic acids, p- Substitution products of amino group-containing styrene such as aminomethylstyrene and urea of monofunctional or polyfunctional iso (thio) cyanate, amino group-containing styrene such as p-aminomethylstyrene and monofunctional or polyfunctional alkyl halide, p- Examples include amino group-containing styrene such as aminomethylstyrene and sulfonamide of monofunctional or polyfunctional sulfonic acid.

About these polymerizable compounds, the details of usage such as the structure, single use or combination, addition amount and the like 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 portion, that is, the cured film, those having three or more functionalities are preferable, and further, different functional numbers and different polymerizable groups (for example, acrylic acid ester, methacrylic acid ester, styrene 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 used in an amount of preferably 5 to 80% by mass, more preferably 25 to 75% by mass, based on the total solid content of the photosensitive layer. Moreover, a polymeric compound may be used independently or may be used together 2 or more types. The use method of the polymerizable compound can be arbitrarily selected from the viewpoints of polymerization inhibition with respect to oxygen, resolution, fogging property, refractive index change, surface adhesiveness, etc. In addition, a layer configuration / coating method such as overcoating can also be carried out.

(D) Binder polymer The chemical structure of the binder polymer used in the photosensitive layer is not particularly limited, but from the viewpoint of solubility in weakly alkaline processing liquid, that is, developability, an organic polymer having an acid group in the side chain is used. An organic polymer containing a carboxylic acid or a salt thereof is particularly preferable.
As the binder polymer, a carboxylic acid-containing alkaline water-soluble or swellable organic polymer is used. Examples of such an organic polymer include addition polymers having a carboxylic acid group in the side chain, such as JP-A-59-44615, JP-B-54-34327, JP-B-58-12577, JP-B-54. -25957, JP-A-54-92723, JP-A-59-53836, JP-A-59-71048, ie, methacrylic acid copolymer, acrylic acid copolymer Polymers, itaconic acid copolymers, crotonic acid copolymers, maleic acid copolymers, partially esterified maleic acid copolymers and the like are useful. As the binder polymer, a copolymer containing a monomer unit derived from a (meth) acrylic acid ester containing a carboxylic acid (salt) group is preferable.
Also useful are acidic cellulose derivatives having a carboxylic acid group in the side chain and those obtained by adding a cyclic acid anhydride to an addition polymer having a hydroxyl group.
Further, Japanese Patent Publication No. 7-120040, Japanese Patent Publication No. 7-120041, Japanese Patent Publication No. 7-120042, Japanese Patent Publication No. 8-12424, Japanese Patent Publication No. 63-287944, Japanese Patent Publication No. 63-287947. The polyurethane resins described in JP-A Nos. 1-271741 and 11-352691 are also useful as alkaline water-soluble or swellable binders.
As the binder polymer, an acrylic resin, a methacrylic resin, or a urethane resin is preferably used.

A suitable example of the binder polymer is a copolymer having a repeating unit containing the following (a) carboxylic acid (including a salt thereof) and (b) a repeating unit imparting radical crosslinkability.
(A) Although it does not specifically limit as a repeating unit containing carboxylic acid, The following structure is used preferably.

In the general formula (I), R ¹ represents a hydrogen atom or a methyl group, and R ² includes two or more atoms selected from the group consisting of a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom. And represents a linking group having 2 to 82 atoms. A represents an oxygen atom or —NR ³ —, and R ³ represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. n represents an integer of 1 to 5.

The linking group represented by R ² in the general formula (I) includes two or more atoms selected from the group consisting of a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom. The number is 2 to 82, preferably 2 to 50, and more preferably 2 to 30. The linking group represented by R ² may have a substituent. The total number of atoms shown here refers to the number of atoms including the substituent when the linking group has a substituent. More specifically, the number of atoms constituting the main skeleton of the linking group represented by R ² is preferably 1-30, more preferably 3-25, and 4-20. More preferred is 5-10. The “main skeleton of the linking group” in the present invention refers to an atom or an atomic group used only for linking A and the terminal COOH in the general formula (I), and particularly when there are a plurality of linking paths. Refers to an atom or atomic group that constitutes a path with the least number of atoms used. Therefore, when a linking group has a ring structure, the number of atoms to be included differs depending on the linking site (for example, o-, m-, p-, etc.).

As the linking group represented by R ² in the general formula (I), more specifically, alkylene, substituted alkylene, arylene, substituted arylene, or a hydrogen atom on any carbon atom constituting these groups is removed ( n + 1) valent groups are exemplified, and those having a structure in which a plurality of these groups are linked by amide bonds or ester bonds are preferred. In particular, those having 5 to 10 atoms constituting the main skeleton of the linking group are preferable. Structurally, the structure is a chain structure having an ester bond in the structure, or a cyclic structure as described above. What has is preferable.
Examples of the substituent that can be introduced into the linking group represented by R ² include monovalent nonmetallic atomic groups other than hydrogen, such as halogen atoms (—F, —Br, —Cl, —I), carbonization. Examples thereof include a hydrogen group (alkyl group, aryl group, alkenyl group, alkynyl group), alkoxy group, and aryloxy group.
A in the general formula (I) is preferably an oxygen atom or —NH— because synthesis is easy.
N in the general formula (I) represents an integer of 1 to 5, and is preferably 1 in terms of printing durability.
(A) When the total number of repeating units is 100, the content of repeating units containing carboxylic acid is 5 to 50, preferably 5 to 25, more preferably 5 to 15 of them.
(A) Specific examples of the repeating unit containing a carboxylic acid include the structures shown in the following (a-1) to (a-12).

  Specific examples of the repeating unit (b) imparting radical crosslinkability include the structures shown in the following (b-1) to (b-11).

  (B) When the total number of repeating units is 100, the content of repeating units imparting radical crosslinkability is from 5 to 90, preferably from 20 to 85, more preferably from 40 to 80.

  The binder polymer used in the present invention may have a repeating unit derived from an ethylenically unsaturated compound containing neither a carboxylic acid nor a group imparting radical crosslinkability as a copolymerization component. Such a repeating unit is preferably a repeating unit derived from (meth) acrylic acid ester or (meth) acrylic acid amide. In particular, a repeating unit derived from an amide group (meth) acrylic acid amide described in paragraphs 0061 to 0084 of JP-A-2007-272134 is preferably used. When the total number of repeating units is 100, the content of such repeating units is 5 to 50, preferably 5 to 35, more preferably 5 to 25 of them.

  In the present invention, a urethane resin having a crosslinkable group in the side chain can also be used as the binder polymer. Here, the crosslinkable group is a group capable of crosslinking the binder polymer by a chemical reaction that occurs in the photosensitive layer when the lithographic printing plate precursor is exposed. The chemical structure is not particularly limited as long as it is a group having such a function. Examples of the functional group capable of addition polymerization include cyclic ether groups such as an ethylenically unsaturated group and an epoxy group / oxetanyl group. 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 atom, an onium salt structure etc. are mentioned, for example. Among these, an ethylenically unsaturated group is preferable and includes functional groups described in paragraphs 0130 to 0139 of JP2007-17948A.

The polyurethane resin having a crosslinkable group in the above side chain not only functions as a film-forming agent for the photosensitive layer but also needs to be dissolved in an alkaline processing solution, so that it may be soluble or swellable in alkaline water. Required. Therefore, in addition to the crosslinkable group, the side chain has an alkali water-soluble group such as a carboxyl group (including salts thereof). 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 can have both good stain resistance and high printing durability. This is preferable.
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 comprises (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 polyaddition reaction of a diol compound having no carboxyl group and (v) a compound having an amino group.

  Examples of the compounds (i), (ii) and (iii) include compounds represented by formulas (4) to (10) and specific examples described in paragraphs 0142 to 0167 of JP-A No. 2007-17948. Can be mentioned.

  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. A diisocyanate compound obtained by addition reaction of a triisocyanate compound and a monofunctional alcohol having a crosslinkable group or 1 equivalent of a monofunctional amine compound, having a crosslinkable group in the side chain, The compounds described in paragraphs 0171 to 0178 of Kaikai 2007-17948 are included.

(Iv) Diol compound having no carboxyl group As a method for introducing an unsaturated group into the side chain of the polyurethane resin, a method using a diol compound containing an unsaturated group in the side chain as a raw material for producing the polyurethane resin is also employed. it can. Such diol compounds include, for example, those commercially available such as trimethylolpropane monoallyl ether, halogenated diol compounds, triol compounds, aminodiol compounds, carboxylic acids containing unsaturated groups, acids Also included are compounds produced by reaction with chlorides, isocyanates, alcohols, amines, thiols, alkyl halide compounds. Specific examples of these compounds include those represented by general formula (A ′), formulas (a) to (e), and formulas (11) to (22) described in paragraphs 0180 to 0225 of JP2007-17948A. Compounds represented and specific compounds are included.

(V) Compound having an amino group In the production of a polyurethane resin, an amino group-containing compound may be further combined and reacted with a diisocyanate compound to form a urea structure and incorporated into the structure of the polyurethane resin. The amino group-containing compounds include compounds represented by formula (31) and formula (32) and specific compounds described in paragraphs 0227 to 0230 of JP2007-17948A.

  The binder polymer used in the present invention has a carboxyl group as described in JP-A-2003-270775 in addition to the polyurethane resin obtained by introducing a crosslinkable group into the side chain during polyurethane synthesis. A polyurethane resin obtained by introducing a crosslinkable group into a polyurethane by a polymer reaction is also included.

  In the present invention, a combination of a polymerizable compound having a melting point of 45 ° C. or higher and a urethane resin having a crosslinkable group having a Tg of 45 ° C. or higher, more preferably 50 ° C. or higher among the urethane resins having the crosslinkable group is particularly preferable. Used. Specific examples of such urethane resins are shown below, but the present invention is not limited thereto.

  In order to maintain the developability of the photosensitive layer, the binder polymer used preferably has an appropriate molecular weight. The weight average molecular weight of the binder polymer is preferably 5,000 to 300,000, more preferably 20,000 to 150,000.

  The binder polymer can be contained in an arbitrary amount in the photosensitive layer. However, when it exceeds 90% by weight, it may not give a preferable result in terms of formed image strength and the like. 90% by weight, more preferably 30 to 80% by weight.

(E) Compound represented by general formula (I)
R ¹ —X Formula (I)
In general formula (I), R ¹ represents a hydrocarbon group having a total carbon number of 8 to 32. A hydrocarbon group having a total carbon number of 12 to 27 is preferable, and a hydrocarbon group having a total carbon number of 15 to 25 is more preferable. The hydrocarbon group may have a substituent such as a halogen group, a hydroxy group, a cyano group, or an amino group. Further, the hydrocarbon group may have an ether bond, an ester bond, or an amide bond. However, the total number of carbon atoms in R ¹ including these substituents and bonds is required to be 8 to 32. When the total number of carbon atoms is less than 8, the effect of improving the inking property is lowered. When the total number of carbon atoms exceeds 32, the solubility of the photosensitive layer in the developer tends to be lowered. Specific examples of preferable R ¹ include linear alkyl groups such as decyl group, dodecyl group, hexadecyl group and octadecyl group, branched alkyl groups such as 14-methylpentadecyl group and 16-methylheptadecyl group, and 9-octadecenyl group. And an alkyl group containing a double bond such as an aryl group such as a nonylphenyl group.

In general formula (I), X represents —CO—Y—R ² , —Y—CO—R ² , —NH—CO—Y—R ² , —O—CO—NH—R ² , —NH—CO. —NH—R ² , —SO ₂ —Y—R ² , —Y—SO ₂ —R ² , —O—SO ₂ —R ² , —CO—O—CO—R ² or —Y—R ³ is shown. . Here, Y represents —O—, —S—, —NR ⁴ — or a single bond. However, when X is —Y—R ³ , Y is not a single bond. R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a hydrocarbon group having a total carbon number of 20 or less. The hydrocarbon group may have a substituent, and preferred examples of the substituent include a halogen group, a hydroxy group, a cyano group, and an amino group. Further, the hydrocarbon group may have an ether bond, an ester bond, or an amide bond. Preferable specific examples of R ² , R ³ and R ⁴ include a hydrogen atom, methyl group, ethyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, hexyl group, phenyl group, A benzyl group, a naphthyl group, a dodecyl group, etc. are mentioned.

Preferred specific examples of the compound represented by formula (I) are shown below, but the present invention is not limited thereto.
Carboxylic acids (X in formula (I) where X is —COOH) include enanthic acid, caprylic acid, pelargonic acid, capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, Examples include stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, heptacosanoic acid, montanic acid, mellicic acid, laccellic acid, undecylenic acid, oleic acid, elaidic acid, celetic acid, erucic acid, brassic acid, etc. It is done. Examples of the carboxylic acid esters exemplified above (X is —COOR ² ) include, for example, carboxylic acid methyl ester, ethyl ester, propyl ester, butyl ester, dodecyl ester, phenyl ester, naphthyl ester, allyl ester, and ( Preferable examples include dodecyl ester, hexadecyl ester, and nonylphenyl ester of (meth) acrylic acid or 4-styrenecarboxylic acid.

Examples of the thiocarboxylic acid ester (X is —COSR ² ) include methylthioester, ethylthioester, propylthioester, butylthioester, and benzylthioester of the carboxylic acid exemplified above. Examples of the carboxylic acid amide (X is —CONH ₂ or —CONHR ² ) include amides of carboxylic acid, methylamide, ethylamide, allylamide, and (meth) acrylic acid or dodecylamide of 4-styrenecarboxylic acid, hexa Examples include decylamide and hexadecylanilide. Examples of urethane and urea derivatives (X is —O—CO—NH—R ² or —NH—CO—NH—R ² ) include, for example, reaction products of octadecylamine and 2-hydroxyethyl acrylate, 2-methacryloyloxy Examples include a reaction product of ethyl isocyanate and hexylamine.

Examples of the alcohol (X is —OH) include octylphenol, nonylphenol, dodecylphenol, 1-docosanol, 1-hexenylphenol, (2-methyl-1-heptenyl) phenol, (2-ethylhexyl) oxyphenol, dodecyloxyphenol, dodeca Noyloxyphenol, oleoylaminophenol, dodecanoylaminophenol, 2-hexylcyclohexanol, N-octyl-2-hydroxynicotinamide, 1-S-octyl-β-D-thioglucopyranoside, sorbitan monolaurate, N -Dodecanoyl-3-pyrrolidinol and the like. Examples of the sulfonic acid derivative (X is —SO ₂ —O—R ² or —SO ₂ —NH—R ² ) include dodecylbenzenesulfonic acid phenyl ester and nonanesulfonic acid anilide. In addition, lactones and lactams such as γ-dodecanolactone and 1-dodecyl-2-pyrrolidinone (X is —CO—O—R ² or CO—NH—R ² ), 2-dodecen-1-ylsuccinic anhydride And cyclic acid anhydrides (X is —CO—O—CO—R ² ) and aldehydes (X is —CO—H) such as 1-docosanal. Of these compounds, compounds that are solid at room temperature are preferred. Further, it is more preferable to have a radical polymerizable functional group such as an allyl group, a (meth) acryloyl group and a styryl group from the viewpoint of improving the film properties of the photosensitive layer.

  The content of the compound represented by the general formula (I) is preferably 0.001 to 10% by weight, more preferably 0.01 to 5% by weight in the solid content of the photosensitive layer. When the content is less than 0.001% by weight, the improvement of the inking property is not sufficient, and when the content is more than 10% by weight, the solubility of the photosensitive layer in the developer may be lowered.

<Other photosensitive layer components>
The photosensitive layer of the present invention can further contain various additives as required. Additives include surfactants for improving developability and improving the surface of the coating, microcapsules for improving developability and printing durability, and improving the developability and dispersion stability of microcapsules. Hydrophilic polymers, colorants and print-out agents for visual recognition of image areas and non-image areas, polymerization inhibitors for preventing unnecessary thermal polymerization of polymerizable compounds during production or storage of the photosensitive layer, oxygen Higher fat derivatives to prevent polymerization inhibition due to polymerization, inorganic fine particles to improve the cured film strength of the image area, hydrophilic low molecular weight compounds to improve developability, co-sensitizers and chain transfer agents to improve sensitivity Further, a plasticizer for improving plasticity can be added. Any of these compounds can be used, for example, JP 2007-171406, JP 2007-206216, JP 2007-206217, JP 2007-225701, JP 2007. The compounds described in JP-A-225702, JP-A-2007-316582, and JP-A-2007-328243 can be used.

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, thiol compounds (for example, 2-mercaptobenzimidazoles, 2-mercaptobenzthiazoles, 2-mercaptobenzoxazoles, 3-mercaptotriazoles, 5-mercaptotetrazoles, etc.) are used. It can be preferably used as a chain transfer agent.
Especially, the thiol compound represented by the following general formula (VI) 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 general formula (VI), R represents a hydrogen atom, an alkyl group which may have a substituent, or an aryl group which may have a substituent, and A has a carbon atom together with an N = CN moiety. It represents an atomic group that forms a membered ring or a six-membered heterocyclic ring, and A may further have a substituent.

<Formation of photosensitive layer>
The photosensitive layer of the present invention is formed by dispersing or dissolving the necessary components described above in a solvent to prepare a coating solution, which is then coated on a support. Solvents used here include ethylene dichloride, cyclohexanone, methyl ethyl ketone, methanol, ethanol, propanol, ethylene glycol monomethyl ether, 1-methoxy-2-propanol, 2-methoxyethyl acetate, 1-methoxy-2-propyl acetate, dimethoxy Examples include ethane, methyl lactate, ethyl lactate, N, N-dimethylacetamide, N, N-dimethylformamide, tetramethylurea, N-methylpyrrolidone, dimethyl sulfoxide, sulfolane, γ-butyllactone, toluene, water, and the like. However, the present invention is not limited to this. A solvent is used individually or in mixture. The solid content concentration of the coating solution is preferably 1 to 50% by mass.
The photosensitive layer of the present invention can be formed by preparing a plurality of coating solutions in which the same or different components are dispersed or dissolved in the same or different solvents, and repeatedly applying and drying a plurality of times.

The photosensitive layer coating amount (solid content) on the support obtained after coating and drying varies depending on the application, but is generally preferably 0.3 to 3.0 g / m ² . Within this range, good sensitivity and good film properties of the photosensitive layer can be obtained.
Various methods can be used as the coating method. Examples thereof include bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, blade coating, and roll coating.

<Protective layer>
In the lithographic printing plate precursor according to the invention, a protective layer (oxygen blocking layer) is preferably provided 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 is ^{20 (mL / m 2 · day} ) Beyond decrease in sensitivity may be incurred. The oxygen permeability A is more preferably in the range of 1.5 ≦ A ≦ 12 (mL / m ² · day), further preferably 2.0 ≦ A ≦ 10.0 (mL / m ² · day). In addition to the oxygen permeability described above, the properties desired for the protective layer are that it does not substantially inhibit the transmission of light used for exposure, has excellent adhesion to the photosensitive layer, and development after exposure. It can be easily removed in the process. Such a device for the protective layer has been conventionally devised and described in detail in US Pat. No. 3,458,311 and Japanese Patent Publication No. 55-49729.

  As a material that can be used for the protective layer, for example, a water-soluble polymer compound having relatively excellent crystallinity is preferable, and specifically, polyvinyl alcohol, vinyl alcohol / vinyl phthalate copolymer, vinyl acetate / vinyl alcohol / phthalate. Water-soluble polymers such as vinyl acid copolymer, vinyl acetate / crotonic acid copolymer, polyvinyl pyrrolidone, acidic celluloses, gelatin, gum arabic, polyacrylic acid, polyacrylamide, etc., may be used alone or in combination. Can be used. 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, and an acetal as long as it contains an unsubstituted vinyl alcohol unit for having necessary oxygen barrier properties and water solubility. Similarly, some of them may have other copolymer components. Specific examples of the polyvinyl alcohol include those having a hydrolysis degree of 70 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. The content rate in the protective layer of polyvinyl alcohol becomes like this. Preferably it is 20-95 mass%, More preferably, it is 30-90 mass%.

  Moreover, well-known modified polyvinyl alcohol can also be used preferably. For example, various hydrophilic modification sites such as anion modification sites modified with anions such as carboxyl groups and sulfo groups, cation modification sites modified with cations such as amino groups and ammonium groups, silanol modification sites, and thiol modification sites are randomly selected. Polyvinyl alcohol having various degrees of polymerization, the anion-modified site, the cation-modified site, the silanol-modified site, the thiol-modified site, the alkoxyl-modified site, the sulfide-modified site, and the ester modification of vinyl alcohol and various organic acids. Examples thereof include polyvinyl alcohol having various polymerization degrees having various modified sites such as a site, an ester-modified site of the anion-modified site and alcohols, an epoxy-modified site, and the like.

Generally, in the plate making process of a lithographic printing plate precursor, when the protective layer and the photosensitive layer in the unexposed area are removed with a developer without removing the protective layer by washing in advance, the water solubility of the protective layer is low. Then, the removability of the photosensitive layer in the unexposed area is deteriorated (it takes time to remove the protective layer and the developability is lowered).
Polyvinyl alcohol has a higher water solubility as the saponification degree is lower in the saponification degree range of 70 mol% to 100 mol%. The acid-modified polyvinyl alcohol described above is also highly water soluble. For this reason, when the average saponification degree of polyvinyl alcohol contained in the protective layer is adjusted to a range of 70 mol% to 93 mol%, or the acid-modified polyvinyl alcohol is contained in the protective layer, the water solubility of the protective layer is increased. Even when the protective layer and the unexposed photosensitive layer are removed with a developer, there is an advantage that the developability is improved and the occurrence of development debris due to the protective layer is reduced.

  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 water-soluble 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 water-soluble polymer compound, and flexibility can be imparted. Anionic surfactants such as sodium acid salts; amphoteric surfactants such as alkylaminocarboxylates and alkylaminodicarboxylates; nonionic surfactants such as polyoxyethylene alkylphenyl ethers based on water-soluble polymer compounds Mass% can be added.

  In addition, adhesion to the photosensitive layer and scratch resistance are extremely important in handling the plate. That is, when a hydrophilic layer made of a water-soluble polymer is laminated on an oleophilic photosensitive layer, film peeling due to insufficient 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 of the protective layer is described in detail in, for example, US Pat. No. 3,458,311 and Japanese Patent Publication No. 55-49729.

Furthermore, the protective layer in the lithographic printing plate precursor according to the invention preferably contains an inorganic stratiform compound for the purpose of improving oxygen barrier properties and photosensitive layer surface protection.
Here, the inorganic layered compound is a particle having a thin flat plate shape. For example, the following general formula A (B, C) _2-5 D ₄ O ₁₀ (OH, F, O) ₂
[However, A is any one of K, Na, and Ca, B and C are any of Fe (II), Fe (III), Mn, Al, Mg, and V, and D is Si or Al. And mica groups such as natural mica and synthetic mica, talc, teniolite, montmorillonite, saponite, hectorite, zirconium phosphate and the like represented by the formula 3MgO.4SiO.H ₂ O.
In the present invention, among the inorganic layered compounds described above, fluorine-based swellable synthetic mica that is a synthetic inorganic layered compound is particularly useful.
The aspect ratio of the inorganic layered compound of the present invention is preferably 20 or more, more preferably 100 or more, and particularly preferably 200 or more. The aspect ratio is the ratio of the thickness to the major axis of the particle, and can be measured, for example, from a projected view of the particle by a micrograph. The larger the aspect ratio, the greater the effect that can be obtained.

  As for the particle diameter of the inorganic stratiform compound used in the present invention, the average major axis is 0.3 to 20 μm, preferably 0.5 to 10 μm, particularly preferably 1 to 5 μm. The average thickness of the particles is 0.1 μm or less, preferably 0.05 μm or less, particularly preferably 0.01 μm or less. For example, among inorganic layered compounds, the size of the swellable synthetic mica that is a representative compound is about 1 to 50 nm in thickness and about 1 to 20 μm in surface size.

  When particles of inorganic layered compounds having a large aspect ratio are contained in the protective layer in this way, the coating film strength is improved and oxygen and moisture permeation can be effectively prevented. Deterioration is prevented, and even when stored for a long time under high-humidity conditions, the storage stability of the planographic printing plate precursor does not deteriorate due to changes in humidity, and the storage stability is excellent.

  It is preferable that content of the inorganic stratiform compound in a protective layer is 5/1-1/100 by mass ratio with respect to the quantity of the binder used for a protective layer. Even when a plurality of types of inorganic layered compounds are used in combination, the total amount of these inorganic layered compounds is preferably the above-described mass ratio.

  In order to disperse the inorganic stratiform compound used in the protective layer, JP-A-2007-171406, JP-A-2007-206216, JP-A-2007-206217, JP-A-2007-225701, JP-A-2007-225702 The methods described in JP-A No. 2007-316582, JP-A 2007-328243 and the like are used.

The coating amount of the protective layer is preferably 0.05 to 10 g / m ^{2 in} terms of the coating amount after drying. When the inorganic layered compound is contained, 0.1 to 0.5 g / The range of m ² is more preferable, and in the case where no inorganic layered compound is contained, the range of 0.5 to 5 g / m ² is more preferable.

[Support]
The support used in the lithographic printing plate precursor according to the invention is not particularly limited as long as it is a dimensionally stable plate-like hydrophilic support. 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 them, 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 the refining technology.
It 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 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 the roughening treatment of 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 (electrochemical surface roughening treatment that dissolves the surface), 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 thus cannot be specified in general. In general, however, an electrolyte concentration of 1 to 80% by mass solution, a liquid temperature of 5 to 70 ° C., a current density of 5 to 60 A / d m 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.

  As the support used in the present invention, the substrate having the above-mentioned surface treatment and having an anodized film may be used as it is, but for further improvement in adhesion to the upper layer, hydrophilicity, resistance to contamination, heat insulation and the like. If necessary, an aqueous solution containing an anodized film micropore expansion treatment, micropore sealing treatment, and a hydrophilic compound described in JP-A Nos. 2001-253181 and 2001-322365 The surface hydrophilization treatment to be immersed can be appropriately selected and performed. Of course, these enlargement processing and sealing processing are not limited to those described above, and any conventionally known method can be performed.

Sealing treatment includes vapor sealing, single treatment with zirconic fluoride, treatment with aqueous solution containing inorganic fluorine compounds such as treatment with sodium fluoride, vapor sealing with addition of lithium chloride, sealing with hot water. Hole processing is also possible.
Of these, sealing treatment with an aqueous solution containing an inorganic fluorine compound, sealing treatment with water vapor, and sealing treatment with hot water are preferable.

As hydrophilization treatment, U.S. Pat. Nos. 2,714,066, 3,181,461,
There are alkali metal silicate methods as described in US Pat. Nos. 3,280,734 and 3,902,734. 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 No.272.

  When using a support with insufficient surface hydrophilicity such as a polyester film as the support of the present invention, it is desirable to apply a hydrophilic layer to make the surface hydrophilic. The hydrophilic layer includes at least one element selected from beryllium, magnesium, aluminum, silicon, titanium, boron, germanium, tin, zirconium, iron, vanadium, antimony, and a transition metal described in JP-A No. 2001-199175. An hydrophilic layer formed by coating a coating solution containing an oxide or hydroxide colloid, or an organic hydrophilic matrix obtained by crosslinking or pseudo-crosslinking an organic hydrophilic polymer described in JP-A No. 2002-79772 A hydrophilic layer having an inorganic hydrophilic matrix obtained by sol-gel conversion consisting of hydrolysis, condensation reaction of polyalkoxysilane, titanate, zirconate or aluminate, or a surface containing a metal oxide A hydrophilic layer made of an inorganic thin film is preferred. Among these, a hydrophilic layer formed by applying a coating solution containing a silicon oxide or a hydroxide colloid is preferable.

  Moreover, when using a polyester film etc. as a support body of this invention, it is preferable to provide an antistatic layer in the hydrophilic layer side of a support body, the opposite side, or both sides. In the case where the antistatic layer is provided between the support and the hydrophilic layer, it also contributes to improving the adhesion with the hydrophilic layer. As the antistatic layer, a polymer layer in which metal oxide fine particles and a matting agent are dispersed as described in JP-A No. 2002-79772 can be used.

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.

(Undercoat layer)
In the lithographic printing plate precursor according to the invention, it is preferable to provide an undercoat layer of a compound containing a polymerizable group on a support. When an undercoat layer is used, the photosensitive layer is provided on the undercoat layer. The undercoat layer reinforces the adhesion between the support and the photosensitive layer in the exposed area, and easily peels the photosensitive layer from the support in the unexposed area, thereby improving developability.
As the undercoat layer, specifically, a silane coupling agent having an addition-polymerizable ethylenic double bond reactive group described in JP-A-10-282679, described in JP-A-2-304441. Preferable examples include phosphorus compounds having an ethylenic double bond reactive group. Particularly preferable compounds include compounds having a polymerizable group such as a methacryl group or an allyl group and a support adsorbing group such as a sulfonic acid group, a phosphoric acid group, or a phosphoric acid ester. A compound having a hydrophilicity-imparting group such as an ethylene oxide group in addition to the polymerizable group and the support-adsorbing group can also be exemplified as a suitable compound.
The coating amount (solid content) of the undercoat layer is preferably from 0.1-100 mg / m ^2, and more preferably 1 to 30 mg / m ^2.

[Back coat layer]
After the surface treatment is applied to the support or after the undercoat layer is formed, a back coat can be provided on the back surface of the support, if necessary.
As the back coat, for example, an organic polymer compound described in JP-A-5-45885, an organic metal compound or inorganic metal compound described in JP-A-6-35174 is obtained by hydrolysis and polycondensation. A coating layer made of a metal oxide is preferable. 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.

[Preparation method of planographic printing plate]
Next, a method for producing a lithographic printing plate according to the present invention will be described.
According to the present invention, the lithographic printing plate precursor used in the present invention is subjected to one-liquid development after image exposure, whereby the lithographic printing plate can be produced by removing the photosensitive layer in the non-image area. When the lithographic printing plate precursor has a protective layer, the protective layer is also removed by this development treatment.

The lithographic printing plate precursor is exposed through a transparent original having a line image, a halftone dot image or the like, or is exposed imagewise by laser beam scanning or the like using digital data.
A desirable wavelength of the light source is 350 nm to 450 nm, and specifically, an InGaN semiconductor laser is suitable.

As available laser light sources of 350 nm to 450 nm, the following can be used.
As a gas laser, an Ar ion laser (364 nm, 351 nm, 10 mW to 1 W), a Kr ion laser (356 nm, 351 nm, 10 mW to 1 W), a He—Cd laser (441 nm, 325 nm, 1 mW to 100 mW), and a solid laser as Nd: YAG (YVO ₄ ) and SHG crystal × 2 combinations (355 nm, 5 mW to 1 W), Cr: LiSAF and SHG crystal combination (430 nm, 10 mW), as a semiconductor laser system, KNbO ₃ ring resonator (430 nm, 30 mW), Combination of waveguide type wavelength conversion element and AlGaAs / InGaAs semiconductor (380 nm to 450 nm, 5 mW to 100 mW), combination of waveguide type wavelength conversion element and AlGaInP, AlGaAs semiconductor (300 nm to 350 nm, 5 mW to 100 mW) ), AlGaInN (350 nm to 450 nm, 5 mW to 30 mW), and N ₂ laser (337 nm, pulse 0.1 to 10 mJ) and XeF (351 nm, pulse 10 to 250 mJ) as a pulse laser. In particular, an AlGaInN semiconductor laser (commercially available InGaN-based semiconductor laser 400 to 410 nm, 5 to 30 mW) is preferable in terms of wavelength characteristics and cost.

As the lithographic printing plate exposure apparatus of the scanning exposure method, there are an inner drum method, an outer drum method, and a flat bed method as an exposure mechanism, and a light source that can continuously oscillate among the light sources can be preferably used. Practically, the following exposure apparatus is particularly preferable because of the relationship between the sensitivity of the lithographic printing plate precursor and the plate making time.
・ Single beam to triple beam exposure equipment that uses one or more gas lasers or solid-state laser light sources so that it becomes a semiconductor laser with a total output of 20 mW or more with an internal drum system. ・ A total output of 20 mW or more with a flat bed system. Multi-beam (1 to 10) exposure equipment that uses one or more semiconductor lasers, gas lasers, or solid-state lasers • Use one or more semiconductor lasers, gas lasers, or solid-state lasers to achieve a total output of 20 mW or more with the external drum system Multi-beam (1 to 9) exposure apparatus ・ Multi-beam (10 or more) exposure apparatus using one or more semiconductor lasers or solid-state lasers so that the total output is 20 mW or more by the external drum system.

In the laser direct drawing type lithographic printing plate precursor as described above, generally the photosensitive material sensitivity X (J / cm ² ), the photosensitive material exposure area S (cm ² ), the power q (W) of one laser light source, Equation (eq1) is established between the number of lasers n and the total exposure time t (s).

  X · S = n · q · t (eq 1)

i) In the case of the internal drum (single beam) system, the laser rotation speed f (radians / s), the sub-scanning length Lx (cm) of the photosensitive material, the resolution Z (dots / cm), and the total exposure time t (s) In general, equation (eq 2) holds.

  f · Z · t = Lx (eq 2)

ii) External drum (multi-beam) method Drum rotation speed F (radians / s), photosensitive material sub-scanning length Lx (cm), resolution Z (dots / cm), total exposure time t (s), number of beams In general, equation (eq 3) is established during (n).

  F.Z.n.t = Lx (eq 3)

iii) Flat head (multi-beam) system polygon mirror rotation speed H (radians / s), photosensitive material sub-scanning length Lx (cm), resolution Z (dots / cm), total exposure time t (s), Equation (eq 4) is generally established between the number of beams (n).

  H.Z.n.t = Lx (eq 4)

Resolution (2560 dpi) required for the actual printing plate, plate size (A1 / B1, sub-scan length 42 inch), exposure conditions of about 20 sheets / hour and photosensitive characteristics of the planographic printing plate precursor of the present invention (photosensitive wavelength, By substituting (sensitivity: about 0.1 mJ / cm ² ) into the above formula, it is understood that a combination with a multi-beam exposure method using a laser having a total output of 20 mW or more is particularly preferable in the planographic printing plate precursor of the present invention. it can. Further, by combining operability, cost, etc., a combination with an external drum type semiconductor laser multi-beam (10 or more) exposure apparatus is most preferable.

  The wavelength of the light source used for image exposure in the present invention is preferably 750 nm to 1400 nm. Any solid-state laser and semiconductor laser can be used as long as they can be exposed at this wavelength. The laser output is preferably 100 mW or more, and a multi-beam laser device is preferably used to shorten the exposure time. The exposure time per pixel is preferably within 20 μsec. The energy applied to the planographic printing plate precursor is preferably 10 to 300 mJ / cm <2>. If the exposure energy is too low, the photosensitive layer is not sufficiently cured. If the exposure energy is too high, the photosensitive layer may be laser ablated and the image may be damaged.

  In the image exposure according to the present invention, the light beams of the light sources can be overlapped for exposure. Overlap means that the sub-scanning pitch width is smaller than the beam diameter. The overlap can be expressed quantitatively by FWHM / sub-scanning pitch width (overlap coefficient), for example, when the beam diameter is expressed by the half width (FWHM) of the beam intensity. In the present invention, the overlap coefficient is preferably 0.1 or more.

The light source scanning method of the exposure apparatus used in the present invention is not particularly limited, and a cylindrical outer surface scanning method, a cylindrical inner surface scanning method, a planar scanning method, and the like can be used. The channel of the light source may be a single channel or a multi-channel, but in the case of a cylindrical outer surface system, a multi-channel is preferably used.

  Next, the development processing step will be described in detail. In a normal processing step, the protective layer is removed by the pre-water washing step, then alkali development is performed, the alkali is removed by the post-water washing step, the gum treatment is performed in the gumming step, and the drying step is performed. In the present invention, development can be performed with one liquid. Preferably, development and gumming can be simultaneously performed by using an aqueous solution containing carbonate ions, hydrogen carbonate ions, and a surfactant and / or a water-soluble polymer compound. Therefore, a post-water washing step is not particularly required, and after performing development and gumming with one liquid, a drying step can be performed. Further, since the protective layer can be removed simultaneously with development and gumming, no pre-water washing step is required. After development and gumming, it is preferable to dry after removing excess processing liquid using a squeeze roller or the like.

The development processing in the present invention can be suitably carried out by an automatic processor equipped with a developer supply means and a rubbing member.
As an automatic processor used for such development processing, for example, Japanese Patent Application Laid-Open Nos. Hei 2-220061 and Hei 60-59351 perform rubbing treatment while conveying a lithographic printing plate precursor after image recording. The automatic processing machine described in US Pat. Nos. 5,148,746, 5,568,768, and British Patent 2,297,719 are used to rub the lithographic printing plate precursor after image recording set on the cylinder while rotating the cylinder. Machine. Among these, an automatic processor using a rotating brush roll as the rubbing member is particularly preferable.

The rotating brush roll that can be preferably used in the present invention can be appropriately selected in consideration of the difficulty of scratching the image area and the stiffness of the support of the lithographic printing plate precursor. As the rotating brush roll, a known one formed by planting a brush material on a plastic or metal roll can be used. For example, as described in JP-A-58-159533, JP-A-3-100554, and JP-A-62-167253, a metal or plastic grooved material in which brush materials are arranged in a row is used as a core. It is possible to use a brush roll that is radially wound around a plastic or metal roll to become a gap.
The brush material includes plastic fibers (for example, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamides such as nylon 6.6 and nylon 6.10, polyacrylonitrile, poly (meth) acrylate, etc. Acrylic and polyolefin synthetic fibers such as polypropylene and polystyrene) can be used. For example, the fiber has a hair diameter of 20 to 400 μm and a hair length of 5 to 30 mm. Can be used.
Furthermore, the outer diameter of the rotating brush roll is preferably 30 to 200 mm, and the peripheral speed at the tip of the brush rubbing the plate surface is preferably 0.1 to 5 m / sec.
Moreover, it is preferable to use two or more rotating brush rolls if necessary.

  The rotating direction of the rotating brush roll may be the same or opposite to the conveying direction of the planographic printing plate precursor. However, when two or more rotating brush rolls are used, at least one rotating brush roll is used. It is preferred that the rotating brush rolls rotate in the same direction and at least one rotating brush roll rotates in the opposite direction. This further ensures the removal of the photosensitive layer in the non-image area. Furthermore, it is also effective to swing the rotating brush roll in the direction of the rotation axis of the brush roll.

  It is preferable to provide a drying step continuously or discontinuously after the development step. Drying is performed by hot air, infrared rays, far infrared rays, or the like.

An example of the structure of an automatic processor suitably used in the method for producing a lithographic printing plate of the present invention is schematically shown in FIG. The automatic processor shown in FIG. 1 basically includes a developing unit 6 and a drying unit 10, and the planographic printing plate precursor 4 is developed and gummed in a developing tank 20 and dried in a drying unit 10.

(Processing liquid)
The processing liquid used in the plate making method of the lithographic printing plate precursor according to the present invention (hereinafter also referred to as developer) is an aqueous solution containing carbonate ion, hydrogen carbonate ion, surfactant and / or water-soluble polymer compound. preferable. Moreover, it is preferable that pH of a process liquid is the range of 8.5-10.8. When the pH is within this range, performance such as good developability, processing stability and printing durability can be obtained. The preferred pH is 9.0 to 10.5, more preferably 9.4 to 10.2. By including a surfactant or a water-soluble polymer compound in the processing liquid, development and gumming can be performed with one liquid.

The developer of the present invention exhibits a buffering action due to the presence of carbonate ions and hydrogen carbonate ions, and can suppress pH fluctuations even when the developer is used for a long period of time. Generation etc. can be suppressed. In order to contain carbonate ion or hydrogen carbonate ion in the developer, carbonate and bicarbonate may be added to the developer, but by adjusting the pH after adding carbonate or bicarbonate, Ions and bicarbonate ions may be generated. The carbonate and bicarbonate are not particularly limited, but are preferably alkali metal salts. Examples of the alkali metal include lithium, sodium, and potassium, and sodium is particularly preferable. The carbonates and bicarbonates may be used alone or in combination of two or more.
The molar ratio of carbonate ion / bicarbonate ion in the developer is 10/90 to 90/10, more preferably 20/80 to 80/20, and still more preferably 30/70 to 70/30. It is.

  The total amount of carbonate and bicarbonate is preferably 0.5 to 20% by mass, more preferably 1 to 15% by mass, and most preferably 2 to 12% by mass with respect to the mass of the developer. If the total amount is 0.5% by mass or more, developability and processing capacity are not lowered, and if it is 20% by mass or less, it is difficult to form precipitates and crystals, and further, it is difficult to gel during neutralization in the waste liquid. Does not interfere with waste liquid treatment.

For the purpose of assisting the fine adjustment of the alkali concentration and the dissolution of the photosensitive layer, another alkali agent such as an organic alkali agent may be supplementarily used together. 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. An organic alkali agent is used individually or in combination of 2 or more types.
Of these, monoethanolamine, diethanolamine, and triethanolamine can be preferably used. 0.5-15 mass% is preferable with respect to a developing solution, and, as for content of an organic alkali agent, 1-10 mass% is more preferable.

<Water-soluble polymer compound>
Examples of the water-soluble polymer compound used in the developer include soybean polysaccharide, modified starch, gum arabic, dextrin, fiber derivatives (eg, carboxymethylcellulose, carboxyethylcellulose, methylcellulose, etc.) and modified products thereof, pullulan, polyvinyl alcohol and the like Derivatives, polyvinylpyrrolidone, polyacrylamide and acrylamide copolymers, vinyl methyl ether / maleic anhydride copolymers, vinyl acetate / maleic anhydride copolymers, styrene / maleic anhydride copolymers, and the like. A preferable acid value of the water-soluble polymer compound is 0 to 3.0 meq / g.

As the soybean polysaccharide, conventionally known ones can be used. For example, as a commercially available product, there is Soya Five (manufactured by Fuji Oil Co., Ltd.), and various grades can be used. What can be preferably used is one in which the viscosity of a 10% by mass aqueous solution is in the range of 10 to 100 mPa / sec.

  As modified starch, what is shown by the following general formula (III) is preferable. For the production of the modified starch represented by the general formula (III), any starch such as corn, potato, tapioca, rice and wheat can be used. These starches can be modified by a method of decomposing in the range of 5 to 30 glucose residues per molecule with an acid or an enzyme, and further adding oxypropylene in an alkali.

  In formula (III), the degree of etherification (degree of substitution) is in the range of 0.05 to 1.2 per glucose unit, n represents an integer of 3 to 30, and m represents an integer of 1 to 3.

Particularly preferable among the water-soluble polymer compounds include soybean polysaccharide, modified starch, gum arabic, dextrin, carboxymethyl cellulose, polyvinyl alcohol and the like.
Two or more water-soluble polymer compounds can be used in combination. The content of the water-soluble polymer compound in the treatment liquid is preferably 0.1 to 20% by mass, and more preferably 0.5 to 10% by mass.

<Surfactant>
Examples of the surfactant used in the developer include anionic, nonionic, cationic, and amphoteric systems.
Anionic surfactants include fatty acid salts, abietic acid salts, hydroxyalkane sulfonates, alkane sulfonates, dialkyl sulfosuccinates, linear alkyl benzene sulfonates, branched alkyl benzene sulfonates, alkyl naphthalene sulfonates. , Alkylphenoxy polyoxyethylene propyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, N-methyl-N-oleyl taurine sodium, N-alkyl sulfosuccinic acid monoamide disodium salts, petroleum sulfonates, sulfated castor oil , Sulfated beef tallow oil, fatty acid alkyl ester sulfates, alkyl sulfates, polyoxyethylene alkyl ether sulfates, fatty acid monoglyceride sulfates Tellurium salts, polyoxyethylene alkylphenyl ether sulfates, polyoxyethylene styryl phenyl ether sulfates, alkyl phosphates, polyoxyethylene alkyl ether phosphates, polyoxyethylene alkylphenyl ether phosphates, styrene-anhydrous Examples thereof include partial saponification products of maleic acid copolymer, partial saponification products of olefin-maleic anhydride copolymer, and naphthalene sulfonate formalin condensates. Among these, dialkyl sulfosuccinates, alkyl sulfate esters and alkyl naphthalene sulfonates are particularly preferably used.

  Examples of the cationic surfactant include alkylamine salts, quaternary ammonium salts, polyoxyethylene alkylamine salts, and polyethylene polyamine derivatives.

  Nonionic surfactants include polyethylene glycol type higher alcohol ethylene oxide adduct, alkylphenol ethylene oxide adduct, fatty acid ethylene oxide adduct, polyhydric alcohol fatty acid ester ethylene oxide adduct, higher alkylamine ethylene oxide adduct, fatty acid. Amidoethylene oxide adducts, fat and oil ethylene oxide adducts, polypropylene glycol ethylene oxide adducts, dimethylsiloxane-ethylene oxide block copolymers, dimethylsiloxane- (propylene oxide-ethylene oxide) block copolymers, and polyhydric alcohol type glycerol Fatty acid ester, fatty acid ester of pentaerythritol, fatty acid ester of sorbitol and sorbitan Fatty acid esters of sucrose, alkyl ethers of polyhydric alcohols, fatty acid amides of alkanolamines.

  In the present invention, ethylene oxide adduct of sorbitol and / or sorbitan fatty acid ester, polypropylene glycol ethylene oxide adduct, dimethylsiloxane-ethylene oxide block copolymer, dimethylsiloxane- (propylene oxide-ethylene oxide) block copolymer, polyhydric alcohol Fatty acid esters are more preferred.

Further, from the viewpoint of stable solubility or turbidity in water, the nonionic surfactant preferably has an HLB (Hydrophile-Lipophile Balance) value of 6 or more, more preferably 8 or more. Further, acetylene glycol-based and acetylene alcohol-based oxyethylene adducts, fluorine-based and silicon-based surfactants can be used in the same manner.
Examples of amphoteric surfactants include 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, alkyldiaminoethylglycine hydrochloride, lauryldimethylaminoacetic acid betaine, and the like.
Surfactants can be used alone or in combination. The content of the surfactant in the developer is preferably from 0.01 to 10% by mass, and more preferably from 0.01 to 5% by mass.

<Other additives>
In addition to the above, the treatment liquid of the present invention may contain a wetting agent, preservative, chelate compound, antifoaming agent, organic acid, organic solvent, inorganic acid, inorganic salt, and the like.

  As the wetting agent, ethylene glycol, propylene glycol, triethylene glycol, butylene glycol, hexylene glycol, diethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, diglycerin and the like are preferably used. The wetting agent may be used alone or in combination of two or more. Generally, the wetting agent is used in an amount of 0.1 to 5% by mass with respect to the treatment liquid.

Preservatives include phenol or derivatives thereof, formalin, imidazole derivatives, sodium dehydroacetate, 4-isothiazolin-3-one derivatives, benzoisothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, benztriazole derivatives Amiding anidine derivatives, quaternary ammonium salts, derivatives such as pyridine, quinoline, guanidine, diazine, triazole derivatives, oxazole, oxazine derivatives, nitrobromoalcohol-based 2-bromo-2-nitropropane-1,3diol, 1, 1-dibromo-1-nitro-2-ethanol, 1,1-dibromo-1-nitro-2-propanol and the like can be preferably used. It is preferable to use two or more kinds of preservatives in combination so as to be effective against various molds and sterilization. The addition amount of the preservative is an amount that exhibits a stable effect on bacteria, fungi, yeast, and the like, and varies depending on the type of bacteria, fungi, yeast, etc., but is 0.01-4 for the treatment liquid. A range of mass% is preferred.

  Examples of the chelate compound include ethylenediaminetetraacetic acid, potassium salt thereof, sodium salt thereof; diethylenetriaminepentaacetic acid, potassium salt thereof, sodium salt thereof; triethylenetetraminehexaacetic acid, potassium salt thereof, sodium salt thereof, hydroxyethylethylenediaminetriacetic acid Nitrilotriacetic acid, sodium salt; 1-hydroxyethane-1,1-diphosphonic acid, potassium salt, sodium salt; aminotri (methylenephosphonic acid), potassium salt, sodium salt And organic phosphonic acids and phosphonoalkanetricarboxylic acids. Organic amine salts are also effective in place of the sodium and potassium salts of the chelating agents. A chelating agent is selected that is stably present in the treatment liquid composition and does not impair the printability. The addition amount is preferably 0.001 to 1.0% by mass with respect to the treatment liquid.

  As the antifoaming agent, a general silicon-based self-emulsifying type, emulsifying type, nonionic HLB 5 or less compound can be used. Silicon antifoaming agents are preferred. Among them, emulsification dispersion type and solubilization can be used. The content of the antifoaming agent is preferably in the range of 0.001 to 1.0% by mass with respect to the treatment liquid.

  Examples of organic acids include citric acid, acetic acid, succinic acid, malonic acid, salicylic acid, caprylic acid, tartaric acid, malic acid, lactic acid, levulinic acid, p-toluenesulfonic acid, xylenesulfonic acid, phytic acid, and organic phosphonic acid. . The organic acid can also be used in the form of its alkali metal salt or ammonium salt. The content of the organic acid is preferably 0.01 to 0.5% by mass with respect to the treatment liquid.

  Examples of the organic solvent include aliphatic hydrocarbons (hexane, heptane, “Isopar E, H, G” (produced by Esso Chemical Co., Ltd.) or gasoline, kerosene, etc.), aromatic hydrocarbons (toluene, xylene, etc.) ) Or halogenated hydrocarbons (methylene dichloride, ethylene dichloride, trichrene, monochlorobenzene, etc.) and polar solvents.

Polar solvents include alcohols (methanol, ethanol, propanol, isopropanol, benzyl alcohol, ethylene glycol monomethyl ether, 2-ethoxyethanol, diethylene glycol monoethyl ether, diethylene glycol monohexyl ether, triethylene glycol monomethyl ether, propylene glycol monoethyl ether , Propylene glycol monomethyl ether, polyethylene glycol monomethyl ether, polypropylene glycol, tetraethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monobenzyl ether, ethylene glycol monophenyl ether, methylphenyl carbinol, n-amyl alcohol, methyl amyl alcohol, etc.) , (Acetone, methyl ethyl ketone, ethyl butyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), esters (ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benzyl acetate, methyl lactate, butyl lactate, ethylene glycol monobutyl acetate, propylene Glycol monomethyl ether acetate, diethylene glycol acetate, diethyl phthalate, butyl levulinate, etc.) and others (triethyl phosphate, tricresyl phosphate, N-phenylethanolamine, N-phenyldiethanolamine, etc.).

  When the organic solvent is insoluble in water, it can be used after being solubilized in water using a surfactant or the like. When the developer contains an organic solvent, the concentration of the solvent is preferably less than 40% by mass from the viewpoint of safety and flammability.

  Examples of inorganic acids and inorganic salts include phosphoric acid, metaphosphoric acid, primary ammonium phosphate, secondary ammonium phosphate, primary sodium phosphate, secondary sodium phosphate, primary potassium phosphate, secondary potassium phosphate, Examples include sodium tripolyphosphate, potassium pyrophosphate, sodium hexametaphosphate, magnesium nitrate, sodium nitrate, potassium nitrate, ammonium nitrate, sodium sulfate, potassium sulfate, ammonium sulfate, sodium sulfite, ammonium sulfite, sodium hydrogen sulfate, nickel sulfate and the like. The content of the inorganic salt is preferably 0.01 to 0.5% by mass with respect to the treatment liquid.

  The temperature of the developer is usually 60 ° C. or lower, preferably 10 ° C. to 50 ° C., more preferably about 15 to 40 ° C.

  The developer described above can be used as a developer and developer replenisher for a lithographic printing plate precursor, and is preferably applied to the automatic processor. When developing using an automatic processor, the developing solution becomes fatigued according to the amount of processing, so the processing capability may be restored using a replenisher or a fresh developer. This replenishing method is also preferably applied to the lithographic printing plate preparation method of the present invention.

In the present invention, as described above, the development treatment may be performed immediately after the exposure step, but a heat treatment step may be provided between the exposure step and the development step. This heat treatment has the effect of improving the printing durability and further improving the uniformity of the image curing degree within the plate surface, and the conditions can be appropriately set within the range where these effects are present. Examples of the heating means include a conventional convection oven, an IR irradiation device, an IR laser, a microwave device, a Wisconsin oven, and the like. For example, it can be carried out by holding the plate surface temperature in the range of 70 to 150 ° C. for 1 second to 5 minutes. Preferably, the temperature is 80 ° C to 140 ° C for 5 seconds to 1 minute, more preferably 90 ° C to 130 ° C for 10 to 30 seconds. This range is preferable in that the above effect can be obtained efficiently and there is no adverse effect such as deformation of the printing plate due to heat.
In the present invention, a development process is performed after the above exposure process and, if necessary, a heat treatment process to obtain a lithographic printing plate. The plate setter used in the exposure process, the heat treatment means used in the heat treatment, and the developing device used in the development process are preferably connected to each other and automatically continuously processed. Specifically, there is a plate making line in which a plate setter and a developing device are coupled by a conveying means such as a conveyor. A heat treatment unit may be provided between the plate setter and the developing device, and the heating unit and the developing device may be integrated.

When the lithographic printing plate precursor is easily affected by ambient light in the working environment, the plate making line is preferably shielded from light by a filter or a cover.
After image formation by development, the entire surface may be exposed with an actinic ray such as ultraviolet light to accelerate the curing of the image area. Examples of the light source for the entire surface exposure include a carbon arc lamp, a mercury lamp, a gallium lamp, a metal halide lamp, a xenon lamp, a tungsten lamp, and various laser lights. Furthermore, in order to obtain sufficient printing durability, the overall exposure amount is preferably at least 10 mJ / cm ² or more, more preferably 100 mJ / cm ² or more.
Heating may be performed simultaneously with the entire surface exposure, and further improvement in printing durability is recognized by heating. Examples of the heating device include a conventional convection oven, an IR irradiation device, an IR laser, a microwave device, a Wisconsin oven, and the like. At this time, the plate surface temperature is preferably 30 ° C to 150 ° C, more preferably 35 ° C to 130 ° C, and still more preferably 40 ° C to 120 ° C. Specifically, the method described in JP-A-2000-89478 can be used.
Further, for the purpose of improving printing durability, the developed printing plate can be heated under very strong conditions. The heating temperature is usually in the range of 200 to 500 ° C. If the temperature is low, sufficient image strengthening action cannot be obtained, and if it is too high, problems such as deterioration of the support and thermal decomposition of the image area may occur.
The lithographic printing plate thus obtained is loaded on an offset printing machine and used for printing a large number of sheets.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these.
[Examples 1-21 and Comparative Examples 1-3]
<Production of support>
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, neutralized with a 20% by mass nitric acid aqueous solution, and then washed with water. This was subjected to an electrolytic surface roughening treatment in a 1% by mass nitric acid aqueous solution using a sinusoidal alternating waveform current at an anode time electricity of 300 coulomb / dm ² . Subsequently, after dipping in a 1% by mass aqueous sodium hydroxide solution at 40 ° C. for 5 seconds and then in a 30% by mass sulfuric acid aqueous solution and desmutting at 60 ° C. for 40 seconds, the current density in a 20% by mass sulfuric acid aqueous solution was 2A / current density. 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 0.28 μm (Ra display according to JIS B0601).

The obtained aluminum plate was immersed in a 40 ° C. aqueous solution containing 4 g / L of polyvinylphosphonic acid for 10 seconds, washed with 20 ° C. tap water for 2 seconds, and dried to obtain a support.
<Formation of photosensitive layer>
On the support, a photosensitive layer coating solution having the following composition was bar-coated, followed by oven drying at 90 ° C. for 60 seconds to form a photosensitive layer having a dry coating amount of 1.3 g / m ² .

(Photosensitive layer coating solution)
・ The following sensitizing dye (A-1) 0.052 g
-0.099g of the following polymerization initiator (B-1)
・ The following ethylenically unsaturated compound (C-1) 0.584 g
(PLEX 6661-O, manufactured by Degussa Japan Co., Ltd.)
・ The following binder polymer (D-1) (average molecular weight: 42,000) 0.389 g
-Compound represented by general formula (I) 0.013 g
(Component (E) listed in Table 1)
-0.047g of the following co-sensitizer (F-1)
・ 0.466 g of ε-phthalocyanine pigment dispersion

(Pigment: 15 parts by mass, dispersant: Polymer (1): 10 parts by mass,
Solvent: cyclohexanone / methoxypropyl acetate / 1-
(Methoxy-2-propanol = 15 parts by mass / 20 parts by mass / 40 parts by mass)
-Thermal polymerization inhibitor 0.003g
N-nitrosophenylhydroxylamine aluminum salt ・ Fluorine-based nonionic surfactant 0.003 g
(Megafuck F780, manufactured by Dainippon Ink Co., Ltd.)
・ 6.63 g of 1-methoxy-2-propanol
・ Methyl ethyl ketone 7.38g

<Formation of protective layer 1>
On the photosensitive layer, a protective layer coating solution (1) having the following composition was applied using a bar so that the dry coating amount was 1.0 g / m ^2, and then dried at 125 ° C. for 70 seconds to form a protective layer. And a lithographic printing plate precursor was obtained.
(Protective layer coating solution (1))
・ The following mica dispersion (1) 4.18g
・ Sulfonic acid-modified polyvinyl alcohol 2.17 g
(Goceran CKS-50, manufactured by Nippon Synthetic Chemical Co., Ltd. [degree of saponification: 99 mol%, average degree of polymerization: 300, degree of modification: about 0.4 mol%])
・ Surfactant (Emalex 710, manufactured by Nippon Emulsion Co., Ltd.) 0.162g
・ Water 45.5g

(Preparation of mica dispersion (1))
To 968 g of water, 32 g of synthetic mica (Somasif ME-100, manufactured by Corp Chemical Co., aspect ratio: 1000 or more) was added and dispersed using a homogenizer until the average particle size (laser scattering method) became 0.5 μm. A dispersion (1) was obtained.

(1) Exposure and development Each lithographic printing plate precursor was subjected to image exposure using a violet semiconductor laser plate setter Vx9600 (equipped with InGaN semiconductor laser 405 nm ± 10 nm emission / output 30 mW) manufactured by FUJIFILM Electronic Imaging Ltd. Image exposure was carried out at a resolution of 2438 dpi using an FM screen (TAFFETA 20) manufactured by Fuji Film Co., Ltd., and 50% flat netting was carried out with a plate exposure of 0.05 mJ / cm ² .
Next, preheating was performed at 100 ° C. for 30 seconds, and then each of the following developers 1 to 11 was used as shown in Table 1, and the immersion time in the developer was measured with an automatic processor having the structure shown in FIG. Development processing was carried out at a conveyance speed at which (development time) was 20 seconds.

  The composition of each developer used is shown below. The amount of each component is parts by mass.

(2) Evaluation <Processability>
As described above, when each lithographic printing plate precursor was subjected to 500 m ² development processing with an automatic processor, the state of occurrence of debris adhering to the wall of the automatic processor was observed. The evaluation was ◯ when no residue was generated, 若干 was slightly generated, but Δ when acceptable, and × when residue was remarkable. The results are listed in Table 1.
<Incarnation>
The developed lithographic printing plate is attached to a printing machine SOR-M manufactured by Heidelberg, and dampening water (EU-3 (an etchant manufactured by FUJIFILM Corporation) / water / isopropyl alcohol = 1/89/10 (volume ratio). )) And TRANS-G (N) black ink (manufactured by Dainippon Ink & Chemicals, Inc.), printing was performed at a printing speed of 6000 sheets per hour. The number of printed sheets required for the ink to be properly applied to the image area and to obtain a print with no problem was evaluated. The smaller the number, the better the inking property. The results are listed in Table 1.

[Examples 22 to 42 and Comparative Examples 4 to 6]
<Creation of support>
The following various surface treatments (a) to (e) were continuously performed. In addition, after each process and water washing, the liquid was removed with the nip roller.
(A) 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 is performed at 50 ° C. for 30 seconds using a 10 mass% sodium aluminate aqueous solution, and then the hair diameter is 0. The aluminum surface 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 30 .mu.m at a brush rotation speed of 250 rpm, and washed thoroughly with water.
(B) This plate was etched by being immersed in a 25% aqueous sodium hydroxide solution at 45 ° C. for 9 seconds, washed with water, further immersed in a 20% 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 .
(C) Next, an electrochemical surface roughening treatment was continuously performed 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 nitric acid electrolysis was 175 C / dm @ 2 when the aluminum plate was the anode. Then, water washing by spraying was performed.
(D) Next, a 0.5% by mass aqueous solution of hydrochloric acid (containing 0.5% by mass of aluminum ions) and an electrolytic solution having a liquid temperature of 50 ° C., with the aluminum plate serving as the anode at an electric charge of 50 C / dm ² . Then, an electrochemical surface roughening treatment was performed in the same manner as in nitric acid electrolysis, and then water washing by spraying was performed.
(E) The plate was provided with a direct current anodic oxide coating of 2.5 g / m ² at a current density of 15 A / dm ² using a 15% sulfuric acid aqueous solution (containing 0.5 mass% of aluminum ions) as an electrolyte, and then washed with water. Dried. 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.
Next, the following undercoat layer coating solution was applied to the surface of the aluminum support with a wire bar and dried at 100 ° C. for 10 seconds. The coating amount was 5 mg / m ² .

(Undercoat layer coating solution)
・ Polyvinylphosphonic acid 0.024g
・ Methanol 27g
・ Ion exchange water 3g

<Formation of photosensitive layer>
On this undercoat layer, a photosensitive layer coating solution having the following composition was applied using a wire bar so that the coating amount after drying was 1.0 g / m ^2, and the temperature was set at 34 ° C. at 115 ° C. using a hot air dryer. The photosensitive layer was formed by drying for 2 seconds.

(Photosensitive layer coating solution)
-0.024g of the following sensitizing dye (A-2)
-0.064 g of the following polymerization initiator (B-2)
-0.094g of the following polymerization initiator (B-3)
・ The following ethylenically unsaturated compound (C-2) 0.327 g
(A-BPE-4, manufactured by Shin-Nakamura Chemical Co., Ltd.)
・ The following binder polymer (D-2) (average molecular weight 100,000) 0.327 g
-Compound represented by general formula (I) 0.010 g
(Component (E) described in Table 1) 0.023 g of the above-mentioned co-sensitizer (F-1)
・ The following co-sensitizer (F-2) 0.074g
・ Copper phthalocyanine pigment 0.071g
-Thermal polymerization inhibitor 0.001g
N-nitrosophenylhydroxylamine aluminum salt ・ Fluorine-based nonionic surfactant 0.003 g
(Megafuck F780, manufactured by Dainippon Ink Co., Ltd.)
・ 3.074 g of 1-methoxy-2-propanol
・ Methyl ethyl ketone 3.224g
・ Methanol 1.675g

<Formation of protective layer 2>
A protective layer coating solution (2) having the following composition was applied on the photosensitive layer using a bar so that the dry coating amount was 1.37 g / m ^2, and then dried at 125 ° C. for 70 seconds to protect the protective layer. And a lithographic printing plate precursor was obtained.
(Protective layer coating solution (2))
-3.258 g of the above mica dispersion
・ Sulphonic acid-modified polyvinyl alcohol 1.307 g
(Goceran CKS-50, manufactured by Nippon Synthetic Chemical Co., Ltd.)
・ Polyvinyl alcohol 0.327g
(PVA405, manufactured by Kuraray Co., Ltd.)
-Vinylpyrrolidone / vinyl acetate copolymer 0.045g
(Luvitec VA64W, manufactured by BASF)
・ Surfactant (Emalex 710, manufactured by Nippon Emulsion Co., Ltd.) 0.032g
・ Water 25.48g

Each lithographic printing plate precursor was exposed with a Trend setter 3244VX manufactured by Creo equipped with a water-cooled 40W infrared semiconductor laser, and an 80% flat screen image with a resolution of 175 lpi, an output of 8 W, an outer drum rotation speed of 206 rpm, and a plate surface energy of 100 mJ / cm ² . did. Without preheating after exposure, each of Developers 1 to 11 was used as shown in Table 2, and the immersion time (development time) in the developer was 20 seconds with the automatic processor having the structure shown in FIG. Development processing was carried out at a conveying speed of
The processability and the inking property were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 2.

As is clear from the results of Tables 1 and 2, the support has a photosensitive layer containing a sensitizing dye, a polymerization initiator, a polymerizable compound, a binder polymer, and a compound represented by the general formula (I). The method for preparing a lithographic printing plate of the present invention in which the lithographic printing plate precursor is subjected to one-liquid treatment after image exposure is excellent in processability, and a lithographic printing plate having excellent inking properties can be obtained.
On the other hand, when the compound represented by the general formula (I) is not included (Comparative Examples 1 and 4) or when the carbon number of R ^{1 in} the general formula (I) is small outside the scope of the present invention (Comparative Example) 2 and 5) have poor inking properties, and when the number of carbon atoms of R ^{1 in} the general formula (I) is large outside the scope of the present invention (Comparative Examples 3 and 6), the processing properties are inferior.

It is explanatory drawing which shows the structure of an automatic processor.

Explanation of symbols

4 Planographic printing plate precursor 6 Developing unit 10 Drying unit 16 Transport roller 20 Developing tank 22 Transport roller 24 Brush roller 26 Squeeze roller 28 Backup roller 36 Guide roller 38 Skewer roller

Claims (7)

(A) A sensitizing dye, (B) a polymerization initiator, (C) a polymerizable compound, (D) a binder polymer, and (E) a photosensitive layer containing a compound represented by the following general formula (I). A method for preparing a lithographic printing plate, comprising subjecting the lithographic printing plate precursor provided thereon to a one-liquid treatment after image exposure.
R ¹ —X Formula (I)
(In the formula, R ¹ represents a hydrocarbon group having 8 to 32 carbon atoms in total. X represents —CO—Y—R ² , —Y—CO—R ² , —NH—CO—Y—R ² , ^{-O-CO-NH-R 2} , -NH-CO-NH-R 2, -SO 2 -Y-R 2, -Y-SO 2 -R 2, -O-SO 2 -R 2, -CO- Represents O—CO—R ² or —Y—R ³ , wherein Y represents —O—, —S—, —NR ^4;
-Or a single bond. However, when X is —Y—R ³ , Y is not a single bond. R ² , R ³ and R ⁴ each represent a hydrogen atom or a hydrocarbon group having a total carbon number of 20 or less. )   The method for producing a lithographic printing plate according to claim 1, wherein the lithographic printing plate precursor has a protective layer on the photosensitive layer.   The method for producing a lithographic printing plate according to claim 2, wherein the protective layer contains acid-modified polyvinyl alcohol.   The treatment liquid in the one-liquid treatment is an aqueous solution containing carbonate ions, hydrogen carbonate ions, a surfactant, and / or a water-soluble polymer compound. A method for preparing a lithographic printing plate.   The treatment liquid in the one-liquid treatment is an aqueous solution containing a surfactant and / or a water-soluble polymer compound and having a pH of 8.5 to 10.8. 2. A method for producing a lithographic printing plate as described in item 1.   The method for producing a lithographic printing plate according to any one of claims 1 to 5, wherein the (D) binder polymer has an acid group in a side chain.   The method for producing a lithographic printing plate according to claim 6, wherein the acid group is a carboxylic acid group.

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