JP2003029427A - Plate making method for planographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plate making method for a planographic printing plate having good developability and free of contamination in printing in a non-image area, ensuring high printing resistance for an image area because high image strength hardly damaged in development is given, free of printing trouble such as blinding in printing, stably attaining good printing performance and having high sensitivity and high productivity as a maintenance-free plate making method using an alkali developing solution of a relatively low pH favorable to the environment and safety and producing no development scum. SOLUTION: A photosensitive planographic printing plate having a photosensitive layer comprising a photopolymerizable photosensitive composition containing a compound having an ethylenically unsaturated double bond, a polymer binder, a photopolymerization initiator and a colorant on an aluminum support is imagewise exposed and the developed with a developing solution of pH 10.0-12.8 containing a compound capable of coordinating to metal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for making a lithographic printing plate, and more particularly, it has high sensitivity and is excellent in development scum, and does not cause print stains due to deterioration of development characteristics over time or repeated use. Regarding plate making method. Further, the lithographic printing plate obtained by this method has little development damage to the image area and a strong image can be obtained, so that there is no failure such as blinding during printing and high printing durability can be realized. it can.

[0002]

2. Description of the Related Art Conventionally, as a negative type photosensitive lithographic printing plate, one having a photosensitive layer containing a diazo resin provided on a hydrophilically treated aluminum plate has been widely used. Therefore, an organic solvent is used as a developing solution. However, there was a concern about the treatment of the developing waste liquid and the influence on the environment. Further, a combination of an orthoquinonediazide compound and a novolac resin is used in the photosensitive layer of a positive-type photosensitive lithographic printing plate, and an alkaline silicate aqueous solution that dissolves the novolac resin has been used as a developer. However, a high pH of about 13 is required to dissolve the novolac resin,
Such a developing solution has a strong irritation to the skin and mucous membranes and is dangerous, and it has been necessary to be sufficiently careful when handling.

On the other hand, a photopolymerization type photosensitive layer (a photopolymerization initiator, a compound having an ethylenically unsaturated double bond, a polymer binder, a coloring pigment, and other surfactants, if necessary, on an aluminum support. A photosensitive lithographic printing plate having a photopolymerizable composition containing a polymerization inhibitor or the like) is also conventionally known, and particularly, a photosensitizer using a combination of a titanocene compound and a dye (titanocene-based photopolymerization initiator) as a polymerization initiator. The lithographic printing plate is widely used because of its excellent sensitivity and stability. As the developer, aqueous solutions of alkali metal silicates, phosphates, carbonates, hydroxides, and organic amine compounds have been proposed.

[0004] For example, in Japanese Patent Laid-Open No. 8-248643
Is an amphoteric surface active with silicic acid alkali salt at high pH of 12 or more.
A developer containing a developing agent is described in JP-A No. 11-65129 as S.
iO ₂/ M₂PH 1 where O (M is an alkali metal) is specified
A developer containing less than 2 alkali silicate silicates is disclosed
There is. In the former case, in addition to handling problems, high p
Due to H, the image area is easily damaged during development,
The problem that sufficient printing durability is not obtained is also used for the latter.
The silicate gels due to a slight decrease in the pH of the developer during use.
There was a problem that it became insoluble.

As a developing solution which does not use an alkali silicate salt, a developing solution containing an alkaline reagent, a complexing agent, an anionic surfactant, an emulsifying agent, an n-alkanoic acid, etc. is disclosed in JP-A-61-190552. West German Patent No. 1984
Japanese Patent No. 605 discloses a developing solution containing an alkaline agent, a complexing agent, an anionic surfactant, amyl alcohol, and N-alkoxyamines. However, both pH
And the organic solvent is contained, the image area is greatly damaged, and satisfactory performance such as printing durability cannot be obtained. As a developing solution having a relatively low pH (pH 12 or less) and containing no alkali silicate, JP-A-2000-
No. 81-11, there is disclosed a developing solution containing an aqueous potassium hydroxide solution containing an anionic surfactant.
Japanese Patent No. 5126 discloses a developer containing an aqueous solution of an alkali metal carbonate having a pH of 8.5 to 11.5.

However, since such a developing solution having a relatively low pH basically has a poor dissolving power of the photopolymerizable photosensitive layer, for example, the aged plate material does not sufficiently develop and a residual film is formed. There was a problem such as. In order to solve these problems, it is necessary to increase the acid value of the polymer binder in the photosensitive layer of the plate material to improve the developability, or to use a monomer having an acid group in combination. When such a high acid value binder is used, printing problems such as a problem that ink does not adhere to the ink during printing (blinding) are likely to occur.

[0007] In addition, if any developer is repeatedly used to reduce waste liquid in consideration of the environment,
Components in the photosensitive layer, especially a photopolymerization initiator and a colorant added for coloring the photosensitive layer are deposited in large amounts as development residue,
Since it accumulates in the developing device, it needs to be removed, which causes problems such as complicated maintenance and eventually a failure. Further, in the market, there is an increasing need for productivity improvement by shortening plate making time in order to reduce costs. It is known that the plate-making time can be significantly shortened by increasing the amount of the initiator and increasing the sensitivity, but due to the problem of the above-mentioned development residue, it was difficult to sufficiently increase the sensitivity by increasing the amount of the initiator.

[0008]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is a maintenance-free plate-making method using an alkaline developer having a relatively low pH, which is environmentally and safety-friendly, and which is good in non-image areas. It has excellent developability, does not stain during printing, and gives strong image strength to the image area with little damage during development, resulting in high printing durability. It is an object of the present invention to provide a plate-making method for a lithographic printing plate which has stable printing, has good printing performance, and has high sensitivity and high productivity.

[0009]

As a result of intensive studies aimed at solving the above-mentioned problems, the present inventor has found that by combining an alkaline solution having a relatively low pH with a compound capable of coordinating with a metal, high printing durability can be obtained. And the occurrence of printing stains, the photosensitive layer components to the developer, particularly the solubility of the titanocene-based photopolymerization initiator or metal phthalocyanine-based color pigment, etc., found to improve the dispersibility does not generate development residue, the present invention. It came to completion.

That is, the present invention is a photosensitive composition comprising a photopolymerizable photosensitive composition containing a compound having an ethylenically unsaturated double bond, a polymer binder, a photopolymerization initiator and a colorant on an aluminum support. A photosensitive lithographic printing plate having a layer is imagewise exposed and then developed with a developing solution containing a compound capable of coordinating to a metal and having a pH of 10.0 to 12.8 to produce a lithographic printing plate. According to the present invention, it is possible to stably obtain a printing plate which is easy to maintain the developing device, is free from printing stains, has high printing durability, high sensitivity, and high productivity.

When a photosensitive lithographic printing plate having a photosensitive layer containing a titanocene-based photopolymerization initiator and / or a metal phthalocyanine-based color pigment is developed with a conventional developing solution, development debris is generated, which is inconvenient. . The development residue was caused by the precipitation of the titanocene photopolymerization initiator and / or the metal phthalocyanine color pigment in the developer. In the conventional method, the titanocene-based photopolymerization initiator and / or the metal phthalocyanine-based color pigment could not be sufficiently dissolved in the developing solution without being precipitated,
In the present invention, by adding a metal coordinating compound to the developer, the titanocene-based photopolymerization initiator and / or the colorant (metal phthalocyanine-based color pigment), which is the main cause of the development dust, can be added to the developer. The dispersibility is improved, and it is possible to prevent the development dust.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The plate making method of the lithographic printing plate of the present invention will be described in detail below. First, the novel developer used for plate making of the planographic printing plate, which is a feature of the present invention, will be described. The developer used in the plate making method of the lithographic printing plate of the invention contains a compound capable of coordinating with a metal and has a pH of 10.0 to 12.8.

The compound capable of coordinating with a metal means a central metal (for example, copper, iron, nickel, or the like) of a metal titanocene and / or a metal phthalocyanine-based color pigment constituting a titanocene photopolymerization initiator which is a main factor of development dust. Manganese, zinc, cobalt, etc.) to form a complex. By forming a complex, the solubility and dispersibility of the photosensitive layer constituents are improved, and development dust is not generated.

The compound capable of forming a complex with a metal includes
Examples thereof include phosphoric acid compounds, phosphonic acid compounds, amine compounds (amino, imide), carboxylic acid compounds, alcohol compounds, sulfonic acid compounds, nitride compounds, azide compounds, peroxo compounds, and π-aryl compounds. Of these compounds, compounds having two or more functional groups are preferable because complex formation is easy. Also,
These compounds may be small molecules, oligomers,
Alternatively, it may be a polymer. Specifically, benzoic acid, iminodiacetic acid, N- (2-hydroxyethyl) iminodiacetic acid, pyridine-2,6-dicarboxylic acid, 7-iodo-8-hydroxyquinoline-5-sulfonic acid, 2-amino -2-Propylphosphonic acid, 1,2-dihydroxybenzene-4-sulfonic acid, Tyrone, Solochrome Violet R, 3-hydroxy-2-naphthoic acid, oxalic acid, oxydiacetic acid, salicylic acid, 5-sulfosalicylic acid, 8 -Hydroxy-7- (arylazo) -quinoline-5-sulfonic acid, phenylserine, acetohydroxamic acid, 3-hydroxy-5,7-disulfo-2-naphthoic acid, 2,3-dihydroxynaphthalene-6-sulfonic acid, Sulfoxine, oxine, acetylacetone, hexafluoroacetylacetone, benzoylacetone,
6,6,7,7,8,8,8-heptafluoro-2,2
-Dimethyl-3,5-octanedione, trifluoroacetylacetone, dibenzoylmethane, dipivaloylmethane, malonic acid, succinic acid, 3,4-dihydroxybenzoic acid, gallic acid, 2- (3,4-dihydroxyphenyl) ) -2- (1,1-Benzopyran) -3,5,7-triol, 3-hydroxy-7-sulfo-2-naphthoic acid, 1,2-dihydroxynaphthalene-4-sulfonic acid, N, N-bis (2-hydroxyethyl) glycine,
N- (phosphonomethyl) -iminodiacetic acid, N- (2-hydroxyethyl) -iminodiacetic acid, iminobis (methylenephosphonic acid), tartaric acid, 1-oxopropane-1,2
-Dicarboxylic acid, propane-1,2,3-tricarboxylic acid, citric acid, desferriferioxamine-B, 1,
7-dihydroxy-4-sulfo-2-naphthoic acid, glutamic acid, pyridoxal-5- (dihydrophosphate), nitrilotriacetic acid, amino (phenyl) methylene-
Diphosphonic acid, ethylenebis [imino- (2-hydroxyphenyl) methylene (methyl) -phosphonic acid], N-
(2-hydroxyethyl) -ethylenedinitrilo-N,
N ′, N′-triacetic acid, ethylenediaminetetraacetic acid, trimethylenedinitrilotetraacetic acid, cyclohexanediaminetetraacetic acid, (2-hydroxytrimethylene) -dinitrilotetraacetic acid, ethylenebis (oxyethylenenitrilo) tetraacetic acid,
N, N, N ', N ", N" -diethylenetriamine-pentaacetic acid, N, N, N', N ", N"', N "'-tetraethylenetetraminehexaacetic acid, semi-xyleno -Le orange,
Semilmethylthymol blue, 3-hydroxyglutamic acid, phosphoserine, amino-3-phosphopropionic acid, glyphosphate, phenylphosphonic acid, mono (2
-Methacryloyloxyethyl) acid phosphate, polyvinylphosphonic acid and the like can be mentioned. Among these, a compound capable of forming a complex with a metal is preferable, a compound capable of forming a complex with a transition metal is more preferable, and a metal titanocene or a metal phthalocyanine pigment contained in a titanocene photopolymerization initiator which is a main factor of development residue. Compounds capable of forming a complex with the central metal of (for example, copper, iron, manganese, nickel, cobalt, zinc, etc.) are particularly preferable. Further, in an aqueous solution in which the metal ion is 1 mol / liter, a compound having a natural logarithm of the complex stability constant of 3 or more is preferable because it is excellent in solubility and dispersibility, more preferably 5 or more, further preferably Is 7 or more.

Further, the compound capable of coordinating with a metal is preferably a polymer which is water-soluble by itself and capable of forming a complex with a metal. Examples of such a polymer include a polymer including a copolymerization component having a hydrophilic group and a copolymerization component having a group capable of coordinating with a metal. The copolymerization component having a hydrophilic group, a hydroxyl group, a polyoxyalkylene group, an amino group, an amide group,
Examples thereof include those having an ammonium group, a carboxyl group and a conjugated base group thereof, a sulfonic acid group and a conjugated base group thereof, a phosphonic acid group and a conjugated base group thereof, and the like. Specific examples of structural units corresponding to these copolymerization components are shown below, but the present invention is not limited thereto.

[0016]

[Chemical 1]

[0017]

[Chemical 2]

The copolymer component having a group capable of coordinating with a metal is preferably one having a structure represented by the general formula (I) and / or (II).

[0019]

[Chemical 3]

(In the formula, R represents a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent, and Y represents a linking group with the main skeleton of the copolymerization component. Ar represents a substituent. Represents a heteroaryl group containing at least one nitrogen atom which may have.

The hydrocarbon group having 1 to 30 carbon atoms includes alkyl group, alkenyl group, alkynyl group,
Examples thereof include an aryl group or a heteroaryl group containing one or more heteroatoms selected from the group consisting of nitrogen atom, oxygen atom and sulfur atom.

Specific examples of the alkyl group include a methyl group,
Ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group,
Undecyl group, dodecyl group, tridecyl group, hexadecyl group, octadecyl group, eicosyl group, isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, isopentyl group, neopentyl group, 1-methylbutyl group, isohexyl group, 2- Ethylhexyl group, 2-
Examples thereof include linear, branched or cyclic alkyl groups having 1 to 30 carbon atoms such as methylhexyl group, cyclopentyl group, cyclohexyl group, 1-adamantyl group and 2-norbornyl group. Specific examples of the alkenyl group include vinyl group, 1-propenyl group, 1-butenyl group,
The number of carbon atoms of 1-methyl-1-propenyl group, 1-cyclopentenyl group, 1-cyclohexenyl group and the like is 1 to 3
Included are linear, branched, or cyclic alkenyl groups up to 0.

Specific examples of the alkynyl group include alkynyl groups having 1 to 30 carbon atoms such as ethynyl group, 1-propynyl group, 1-butynyl group and 1-octynyl group. Specific examples of the aryl group include 1 to 4
Those in which individual benzene rings form a condensed ring, and those in which a benzene ring and an unsaturated five-membered ring form a condensed ring can be mentioned, and specific examples include a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, Examples thereof include indenyl groups, acenabutenyl groups, fluorenyl groups, pyrenyl groups, and other alur groups having 1 to 30 carbon atoms.

The heteroaryl group containing at least one heteroatom selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom is one or more heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom. The heteroaryl group can be exemplified by removing one hydrogen atom on the heteroaromatic ring containing the heteroaromatic ring. Specific examples of the heteroaromatic ring containing at least one heteroatom selected from the group consisting of nitrogen atom, oxygen atom and sulfur atom include pyrrole, furan,
Thiophene, pyrazole, imidazole, triazole, oxazole, isoxazole, oxadiazole, thiazole, thiadiazole, indole, carbazole, benzofuran, dibenzofuran, thianaphthene, dibenzothiophene, indazolebenzimidazole, anthranil, benzisoxazole, benzoxazole, benzothiazole, Purine, pyridine,
Examples thereof include pyridazine, pyrimidine, pyrazine, triazine, quinoline, acridine, isoquinoline, phthalazine, quinazoline, quinoxaline, naphthyridine, phenanthroline, pteridine and the like.

One or more of these hydrocarbon groups having 1 to 30 carbon atoms may be substituted with any substituent. Examples of the substituent include a monovalent non-metal atomic group other than hydrogen, and a halogen atom (-F, -Br,-).
Cl, -I), hydroxyl group, alkoxy group, aryloxy group, mercapto group, alkylthio group, arylthio group, alkyldithio group, aryldithio group, amino group, N-alkylamino group, N, N-dialkylamino group, N -Arylamino group, N, N-diarylamino group, N-alkyl-N-arylamino group, acyloxy group, carbamoyloxy group, N-alkylcarbamoyloxy group, N-arylcarbamoyloxy group, N,
N-dialkylcarbamoyloxy group, N, N-diarylcarbamoyloxy group, N-alkyl-N-arylcarbamoyloxy group, alkylsulfoxy group, arylsulfoxy group, acylthio group, acylamino group, N
-Alkylacylamino group, N-arylacylamino group, ureido group, N'-alkylureido group, N ',
N'-dialkylureido group, N'-arylureido group, N ', N'-diarylureido group, N'-alkyl-N'-arylureido group, N-alkylureido group, N-arylureido group, N' -Alkyl-N-alkylureido group, N'-alkyl-N-arylureido group, N ', N'-dialkyl-N-alkylureido group, N', N'-dialkyl-N-arylureido group, N ' -Aryl-N-alkylureido group, N'-
Aryl-N-arylureido group, N ', N'-diaryl-N-alkylureido group, N', N'-diaryl-N-arylureido group, N'-alkyl-N '
-Aryl-N-alkylureido group, N'-alkyl-N'-aryl-N-arylureido group, alkoxycarbonylamino group, aryloxycarbonylamino group, N-alkyl-N-alkoxycarbonylamino group, N-alkyl -N-aryloxycarbonylamino group, N-aryl-N-alkoxycarbonylamino group, N-aryl-N-aryloxycarbonylamino group, formyl group, acyl group, carboxyl group and its conjugate base group, alkoxycarbonyl group, Aryloxycarbonyl group, carbamoyl group, N-alkylcarbamoyl group, N, N-dialkylcarbamoyl group, N-arylcarbamoyl group, N, N-diarylcarbamoyl group,
N-alkyl-N-arylcarbamoyl group, alkylsulfinyl group, arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, sulfo group (-SO
₃ H) and its conjugate base group, an alkoxysulfonyl group,
Aryloxysulfonyl group, sulfinamoyl group, N-
Alkylsulfinamoyl group, N, N-dialkylsulfinamoyl group, N-arylsulfinamoyl group,
N, N-diarylsulfinamoyl group, N-alkyl-N-arylsulfinamoyl group, sulfamoyl group, N-alkylsulfamoyl group, N, N-dialkylsulfamoyl group, N-arylsulfamoyl group ,
N, N-diarylsulfamoyl group, N-alkyl-
N- arylsulfamoyl group, N- acylsulfamoyl group and a conjugate base group, N- alkylsulfonylsulfamoyl group _{(-SO 2 NHSO 2 (alkyl)} ) and its conjugated base group, N- aryl sulfonylsulfamoyl Le Famoiru group _{(-SO 2 NHSO 2 (aryl)} ) and its conjugated base group, N- alkylsulfonylcarbamoyl group (-C
ONHSO ₂ (alkyl)) and its conjugate base group, N
-Arylsulfonylcarbamoyl group (-CONHSO
₂ (aryl)) and its conjugated base group, alkoxysilyl group (-Si (Oalkyl) ₃ ), aryloxysilyl group (-Si (Oaryl) ₃ ), hydroxysilyl group (-Si (OH) ₃ ) and its conjugate. base group, a phosphono group (-PO ₃ H ₂₎ and its conjugated base group, a dialkyl phosphono group _{(-PO 3 (alkyl) 2)} , diaryl phosphono group _{(-PO 3 (aryl) 2)} , alkyl aryl phosphono group _{(-PO 3 (alkyl) (aryl} )), monoalkyl phosphono group (-PO ₃ H (alkyl)) and its conjugated base group, monoaryl phosphono group (-PO ₃ H
(Aryl)) and its conjugated base group, a phosphonooxy group (-OPO ₃ H ₂₎ and its conjugated base group, a dialkyl phosphono group _{(-OPO 3 (alkyl) 2)} , diaryl phosphono group (-OPO ₃ ( aryl) ₂ ), an alkylaryl phosphonooxy group (-OPO ₃ (alky
l) (aryl)), monoalkyl phosphono group (-OPO ₃ H (alkyl)) and its conjugated base group,
Monoarylphosphono group (-OPO ₃ H (ary
l)) and its conjugated base groups, cyano groups, nitro groups, aryl groups, alkyl groups, alkenyl groups, alkynyl groups.

The linking group represented by Y is an oxygen atom,
A substituted or unsubstituted divalent hydrocarbon group having 1 to 30 carbon atoms, which may be interrupted once or more by a functional group containing one or more hetero atoms selected from the group consisting of nitrogen atom and sulfur atom, Can be mentioned.

Ar is a heteroaryl group containing one or more nitrogen atoms, specifically, pyrrol, pyridine, pyrazole, imidazole, triazole, tetrazole, isoxazole, oxazole which may have a substituent. , Isothiazole, thiazole, thiadiazole, indole, carbazole, azaindole, indazole, benzimidazole, benzotriazole,
On the carbon atom constituting the nitrogen-containing heteroaromatic ring such as benzisoxazole, benzoxazole, benzothiazole, purine, pyridazine, pyrimidine, pyrazine, triazine, quinoline, isoquinoline, acridine, phthalazine, quinazoline, quinoxaline, naphthyridine, phenanthroline, and pteridine. Remove one hydrogen atom from
The thing based on a valence can be mentioned.

In the following, the general formula (I) and / or (I
Specific examples of the structural unit corresponding to the copolymerization component having the structure represented by I) are shown below, but the present invention is not limited thereto.

[0029]

[Chemical 4]

[0030]

[Chemical 5]

The copolymerization component having a hydrophilic group and the copolymerization component having a group capable of coordinating with a metal are contained in the polymer at least one type each, but may be two or more types. Furthermore, in addition to the copolymerization component having these hydrophilic groups and the copolymerization component having a group capable of coordinating with a metal,
It is also possible to introduce a copolymerization component of (3) to obtain a ternary or higher copolymer. As such a copolymerization component, conventionally known components can be used without limitation. Specifically, "Polymer Data Handbook-Basic-" (Polymer Society of Japan, Baifukan,
1986) ”. Such a third copolymerization component may be used alone or in combination of two or more.

Regarding the introduction ratio of the copolymerization component having a hydrophilic group and the copolymerization component having a group capable of coordinating to a metal in the above-mentioned polymer, what kind of structure should be selected, or the composition of the developing solution (eg, It can be arbitrarily set depending on the pH, the type and content of other components such as a surfactant and the like. Preferably, the copolymerization component having a hydrophilic group and the copolymerization component having a group capable of coordinating to a metal (when two or more kinds are used,
The total amount thereof) is at least 5 mol% or more, more preferably 10 mol% or more, still more preferably 20 mol% or more. When the content is less than 5 mol%, precipitation of dust tends to occur. Further, the molecular weight of the polymer can also be arbitrarily set. When the molecular weight is high, dust is likely to be generated, and when it is too low, dust is easily generated. The preferable molecular weight is 2,000 to 1,0.
0,000, more preferably 5,000 to 500,0
00, more preferably 10,000 to 200,000
Is the range.

The compounds capable of coordinating with these metals can be used alone or in combination. The content of the compound capable of coordinating to these metals in the developer is preferably 1 to 30% by weight, more preferably 3 to 25% by weight, and further preferably 5 to 20% by weight in terms of active ingredient. Here, if the amount added is too small, the developability and the solubility of the components of the photosensitive layer are lowered, and if it is too large, the printing durability of the printing plate may be lowered.

The developing solution used in the method of the present invention preferably contains an inorganic alkaline agent. The inorganic alkaline agent is not particularly limited, for example,
Trisodium phosphate, potassium, ammonium,
Inorganic alkali agents such as sodium carbonate, potassium carbonate, ammonium, sodium hydrogencarbonate, potassium, ammonium, sodium borate, potassium, ammonium, sodium hydroxide, potassium, ammonium, and lithium are included. . In addition, an organic alkaline agent may be supplementarily used for the purpose of minute adjustment of the alkali concentration and assisting the solubility of the photosensitive layer. As the organic alkaline agent, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, Examples thereof include diisopropanolamine, ethyleneimine, ethylenediamine, pyridine, tetramethylammonium hydroxide and the like. These alkaline agents may be used alone or in combination of two or more.

The pH of the developer used in the present invention is 1
Although it is from 0.0 to 12.8, if it is below the range, image formation cannot be carried out. On the contrary, if it exceeds the range, there is a problem that over-development occurs and damage of development in an exposed portion becomes strong. A more preferable pH range is 11.0 to 12.5.

The developer used in the present invention may further contain a surfactant as described below. Examples of the surfactant that may be added include polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether and other polyoxyethylene alkyl ethers, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl. Polyoxyethylene alkyl allyl ethers such as phenyl ether, polyoxyethylene alkyl esters such as polyoxyethylene stearate, sorbitan monolaurate, sorbitan monostearate, sorbitan distearate, sorbitan monooleate, sorbitan sesquioleate , Sorbitan trioleate and other sorbitan alkyl esters, glycerol monostearate, glycerol monooleate and other monoglyceride alkyls Nonionic surfactants such as steals; alkylbenzene sulfonates such as sodium dodecylbenzene sulfonate, sodium butylnaphthalene sulfonate, sodium pentylnaphthalene sulfonate, sodium hexylnaphthalene sulfonate, sodium octylnaphthalene sulfonate and the like alkylnaphthalene sulfonates Salts, alkyl sulfates such as sodium lauryl sulfate, alkyl sulfonates such as sodium dodecyl sulfonate, anion surfactants such as sulfosuccinate ester salts such as sodium dilauryl sulfosuccinate; alkyl betaines such as lauryl betaine and stearyl betaine , Amphoteric surfactants such as amino acids can be used, and among these, polyoxyalkylene ether having a structure of the following general formula (III) is used. Nonionic surfactant containing a group are preferably used.

R ¹⁴ —O— (R ¹⁵ —O) _n H (III)

In the formula, R ¹⁴ is an alkyl group having 3 to 15 carbon atoms which may have a substituent, an aromatic hydrocarbon group having 6 to 15 carbon atoms which may have a substituent, or a substituent. A heterocyclic aromatic group having 4 to 15 carbon atoms which may have (as a substituent, an alkyl group having 1 to 20 carbon atoms, Br, Cl, I
Halogen atom such as C6 to C15 aromatic hydrocarbon group, C7 to C17 aralkyl group, C1 to C20 alkoxy group, C2 to C20 alkoxycarbonyl group, and C2 to C15. And an acyl group. And R ¹⁵ is an alkylene group having 1 to 100 carbon atoms which may have a substituent (wherein, as the substituent, 1 to 20 carbon atoms are shown).
And an aromatic hydrocarbon group having 6 to 15 carbon atoms. ) Is shown and n represents the integer of 1-100.

The portion of (R ¹⁵ --O) _{n in} formula (III) is
The structures may be different from each other within the above range. Specific examples include a combination of ethyleneoxy group and propyleneoxy group, ethyleneoxy group and isopropyloxy group, ethyleneoxy group and butyleneoxy group, ethyleneoxy group and isobutylene group, etc., which are connected in a random or block form. . These surfactants can be used alone or in combination. The content of these surfactants in the developer is preferably 0.1 to 20% by weight in terms of active ingredient.

The developer of the present invention contains, in addition to the above components,
If necessary, the following components can be used in combination.
For example, benzoic acid, phthalic acid, p-ethylbenzoic acid, p-
n-propylbenzoic acid, p-isopropylbenzoic acid, p
-N-butylbenzoic acid, pt-butylbenzoic acid, p-
Organic carboxylic acids such as t-butylbenzoic acid, p-2-hydroxyethylbenzoic acid, decanoic acid, salicylic acid, and 3-hydroxy-2-naphthoic acid; isopropyl alcohol,
Organic solvents such as Hendyl alcohol, ethyl cellosolve, butyl cellosolve, phenyl cellosolve, propylene glycol, diacetone alcohol, etc .; in addition, chelating agents, reducing agents, dyes, pigments, water softeners, preservatives, defoaming agents, etc. .

Next, the photosensitive lithographic printing plate used in the present invention will be described. The photopolymerizable photosensitive composition constituting the photosensitive layer of the photosensitive lithographic printing plate used in the present invention, a photopolymerization initiator, a compound having an ethylenically unsaturated double bond, a colorant and a polymer binder are essential components. If desired, various compounds such as a plasticizer and a thermal polymerization inhibitor can be used in combination.

The system photopolymerization initiator contained in the photosensitive layer of the photosensitive lithographic printing plate of the present invention includes various photopolymerization initiators known in patents, literatures, etc. depending on the wavelength of the light source used.
Alternatively, a combination system of two or more photopolymerization initiators (photopolymerization initiator system) can be appropriately selected and used. When using a blue semiconductor laser, Ar laser, second harmonic of infrared semiconductor laser, or SHG-YAG laser as the light source,
Various photopolymerization initiators (systems) have been proposed, for example certain photoreducible dyes such as those described in US Pat. No. 2,850,445, such as rose bengal, eosin, erythrosine, or dyes and initiators. Systems by combination with agents, such as complex initiation system of dye and amine (Japanese Patent Publication No. 44-2
No. 0189), a combination system of a hexaarylbiimidazole, a radical generator and a dye (Japanese Patent Publication No. 45-37377).
No.), a system of hexaarylbiimidazole and p-dialkylaminobenzylidene ketone (Japanese Patent Publication No. 47-2528).
JP-A-54-155292), a system of a cyclic cis-α-dicarbonyl compound and a dye (JP-A-48-84183).
No.), a system of cyclic triazine and merocyanine dye (JP-A-54-151024), a system of 3-ketocoumarin and an activator (JP-A-52-112681, JP-A-58-155).
03), biimidazole, styrene derivative, thiol system (JP-A-59-140203), organic peroxide and dye system (JP-A-59-1504, JP-A-59-14).
0203, JP-A-59-189340, JP-A-62.
-174203, Japanese Examined Patent Publication No. 62-1641, U.S. Pat. No. 4,766,055), a system of a dye and an active halogen compound (JP-A-63-1718105, JP-A-63-258).
903, JP-A-2-63054, etc.), dye-borate compound systems (JP-A-62-143044, JP-A-62-150242, JP-A-64-13140, JP-A-64-13141). JP-A-64-13142,
JP-A-64-13143, JP-A-64-13144
JP-A 64-17048, JP-A 1-222900
3, JP-A 1-298348, JP-A 1-1382.
No. 04, etc.), a system of a dye having a rhodanine ring and a radical generator (JP-A-2-179643, JP-A-2-24).
4050), a system of a titanocene and a 3-ketocoumarin dye (JP-A-63-221110), a system in which a titanocene and a xanthene dye, and an addition-polymerizable ethylenically unsaturated compound containing an amino group or a urethane group are combined (JP-A-Hei-HEI). No. 4-221958, JP-A-4-219756.
No.), a system of titanocene and a specific merocyanine dye (JP-A-6-295061), a system of a dye having a titanocene and a benzopyran ring (JP-A-8-334897), and the like.

In the photosensitive layer of the photosensitive lithographic printing plate used in the present invention, a particularly preferred photopolymerization initiator (system) contains at least one titanocene. The titanocene compound used as the photopolymerizable initiator (system) in the present invention may be any titanocene compound capable of generating an active radical when irradiated with light in the presence of other sensitizing dyes. , For example, JP-A-59-152396.
JP-A-61-151197, JP-A-63-414
83, JP-A-63-41484, JP-A-2-249.
Known compounds described in JP-A-2-291, JP-A-3-27393, JP-A-3-12403, and JP-A-6-41170 can be appropriately selected and used.

More specifically, di-cyclopentadienyl-Ti-di-chloride, di-cyclopentadienyl-Ti-bis-phenyl, di-cyclopentadienyl-Ti-bis-2,3,3. 4,5,6-Pentafluorophen-1-yl (hereinafter also referred to as “T-1”), di-cyclopentadienyl-Ti-bis-2,3,5,6-tetrafluorophen-1- Di-cyclopentadienyl-Ti-bis-2,4,6-trifluorophenyl-
1-yl, di-cyclopentadienyl-Ti-bis-
2,6-difluorophenyl-1-yl, di-cyclopentadienyl-Ti-bis-2,4-difluorophenyl-
1-yl, di-methylcyclopentadienyl-Ti-bis-2,3,4,5,6-pentafluorophenyl-1-
Di-methylcyclopentadienyl-Ti-bis-
2,3,5,6-tetrafluorophenyl-1-yl, di-methylcyclopentadienyl-Ti-bis-2,4-
Difluorophenyl-1-yl, bis (cyclopentadienyl) -bis (2,6-difluoro-3- (pyr-1-
Ilyl) phenyl) titanium (hereinafter, also referred to as “T-2”) and the like.

These titanocene compounds can be further subjected to various chemical modifications for improving the characteristics of the photosensitive layer. For example, a sensitizing dye, a bond with an addition-polymerizable unsaturated compound or other radical generating part, introduction of a hydrophilic site, improvement of compatibility, introduction of a substituent for suppressing crystal precipitation, introduction of a substituent for improving adhesion. A method such as polymerization can be used. The usage of these titanocene compounds can also be arbitrarily set according to the performance design of the photosensitive lithographic printing plate, like the addition-polymerizable compounds described above. For example, the compatibility with the photosensitive layer can be increased by using two or more kinds in combination. A larger amount of the photopolymerization initiator such as the titanocene compound is usually advantageous in terms of photosensitivity, and is 0.5 to 80 parts by weight, preferably 1 to 100 parts by weight of the nonvolatile component of the photosensitive layer. Sufficient photosensitivity can be obtained by using in the range of 50 parts by weight. The amount of these photopolymerization initiators used is 3.0 to 45% by weight, preferably 5.0 to 40% by weight, and more preferably 10 to 3% by weight based on the total components of the photosensitive layer.
It is used in an amount of 5% by weight, particularly preferably 15 to 30% by weight. If the addition amount is less than 3.0% by weight, the sensitivity becomes insufficient, and if it is more than 45% by weight, development dust occurs.

Further, in the photosensitive layer of the photosensitive lithographic printing plate used in the method of the present invention, in combination with the above photopolymerization initiator,
By using the co-sensitizer, the sensitivity of the photosensitive layer can be further improved. Although their mechanism of action is not clear, it is thought that most of them are based on the following chemical processes. That is, various intermediate active species (radicals, peroxides, radicals, peroxides, etc.) generated in the process of the photoreaction initiated by the light absorption of the photopolymerization initiator (system) described above and the subsequent addition polymerization reaction.
It is presumed that the co-sensitizer reacts with an oxidizing agent, a reducing agent, etc.) to generate a new active radical. These are roughly (a) those that can be reduced to produce active radicals, (b) those that can be oxidized to produce active radicals,
(C) It can be classified into a group that reacts with a radical having low activity and converts into a radical having higher activity, or that acts as a chain transfer agent. However, as to which of these individual compounds belongs, there is a common theory. Often not.

(A) Compound which is reduced to generate an active radical Compound having a carbon-halogen bond: It is considered that the carbon-halogen bond is reductively cleaved to generate an active radical. Specifically, for example, trihalomethyl-s-triazines and trihalomethyloxadiazoles can be preferably used. Compound having nitrogen-nitrogen bond: It is considered that the nitrogen-nitrogen bond is reductively cleaved to generate an active radical. Specifically, hexaarylbiimidazoles and the like are preferably used. Compound having oxygen-oxygen bond: It is considered that the oxygen-oxygen bond is reductively cleaved to generate an active radical. Specifically, for example, organic peroxides and the like are preferably used. Onium compound: Reductively carbon-hetero bond or oxygen-
It is considered that the nitrogen bond is cleaved to generate an active radical. Specifically, for example, diaryliodonium salts,
Triarylsulfonium salts, N-alkoxypyridinium (azinium) salts and the like are preferably used. Ferrocene, iron arene complexes: An active radical can be reductively generated.

(B) Compound that oxidizes to produce an active radical Alkylate complex: It is considered that an active radical is produced by the oxidative cleavage of a carbon-hetero bond. Specifically, for example, triarylalkyl borates are preferably used. Alkylamine compound: It is considered that the C—X bond on the carbon adjacent to the nitrogen is cleaved by oxidation to generate an active radical. As X, a hydrogen atom, a carboxyl group, a trimethylsilyl group, a benzyl group and the like are preferable.
Specific examples include ethanolamines, N-phenylglycines, N-trimethylsilylmethylanilines, and the like. Sulfur-containing and tin-containing compounds: The above amines in which the nitrogen atom is replaced with a sulfur atom or a tin atom can generate an active radical by the same action. It is also known that a compound having an S-S bond is sensitized by cleavage of S-S.

Α-Substituted methylcarbonyl compound: An active radical can be generated by the cleavage of the carbonyl-α carbon bond by oxidation. Further, the one in which carbonyl is converted to oxime ether also exhibits the same action. In particular,
2-alkyl-1- [4- (alkylthio) phenyl]
Examples thereof include -2-morpholinopronone-1 and oxime ethers obtained by reacting these with hydroxyamines and then etherifying N-OH. Sulfinates: An active radical can be reductively generated. Specifically, sodium arylsulfinate and the like can be mentioned.

(C) Compounds that react with radicals to be converted into highly active radicals or act as chain transfer agents: For example, compounds having SH, PH, SiH and GeH in the molecule are used. These can donate hydrogen to a radical species having low activity to generate a radical, or can generate a radical by deprotonating after being oxidized. Specific examples include 2-mercaptobenzimidazoles and the like. More specific examples of these co-sensitizers are described, for example, in JP-A No. 9-236913, as additives for the purpose of improving sensitivity. Some of them will be illustrated below, but the materials used for the photosensitive layer of the photosensitive lithographic printing plate of the invention are not limited to these.

[0051]

[Chemical 6]

These co-sensitizers can also be subjected to various chemical modifications in order to improve the characteristics of the photosensitive layer. For example, a sensitizing dye, titanocene, a bond with an addition-polymerizable unsaturated compound or other radical-generating part, introduction of a hydrophilic moiety, improvement of compatibility, introduction of a substituent for suppressing crystal precipitation, and a substituent for improving adhesion. Methods such as introduction and polymerization can be used. These co-sensitizers can be used alone or in combination of two or more. The amount used is 0.05-100 parts by weight, preferably 1-80, relative to 100 parts by weight of the compound having an ethylenically unsaturated double bond.
A suitable range is parts by weight, more preferably 3 to 50 parts by weight.

Next, the ethylenically unsaturated compound will be described. The ethylenically unsaturated compound contained in the photosensitive layer of the photosensitive lithographic printing plate used in the present invention means that when the photopolymerizable photosensitive composition is exposed to actinic rays, it undergoes addition polymerization by the action of a photopolymerization initiator. It is a compound having an ethylenically unsaturated bond that can be crosslinked and cured. The addition-polymerizable compound containing an ethylenic double bond can be arbitrarily selected from compounds having at least one terminal ethylenically unsaturated bond, preferably two or more. For example, it has a chemical form such as a monomer, a prepolymer, that is, a dimer, a trimer and an oligomer, or a mixture thereof and a copolymer thereof.

Examples of the monomers and copolymers thereof include esters of unsaturated carboxylic acids (eg acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid) with aliphatic polyhydric alcohol compounds. , Amides of unsaturated carboxylic acids and aliphatic polyvalent amine compounds, and the like. Specific examples of monomers of the 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 pentaacrylate, dipentaerythritol hexaacrylate, sorbitol triacrylate, sorbitol tetraacrylate, sorbitol pentaacrylate, sorbitol hexaacrylate, tri (acryloyloxyethyl) isocyanurate, polyester There are acrylate oligomers and the like.

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, dipentaerythritol pentamethacrylate, sorbitol trimethacrylate, sorbitol tetramethacrylate , Bis [p- (3--methacryloxy-2-hydroxypropoxy) phenyl] dimethyl methane, bis - [p- (methacryloxyethoxy) phenyl] dimethyl methane.

As the itaconic acid ester, ethylene glycol diitaconate, propylene glycol diitaconate, 1,3-butanediol diitaconate,
1,4-butanediol diitaconate, tetramethylene glycol diitaconate, pentaerythritol diitaconate, sorbitol tetritaconate and the like. Examples of crotonic acid esters include ethylene glycol dicrotonate, tetramethylene glycol dicrotonate, pentaerythritol dicrotonate, and sorbitol tetradicrotonate. Examples of the isocrotonic acid ester include ethylene glycol diisocrotonate, pentaerythritol diisocrotonate, and sorbitol tetraisocrotonate.

Examples of the maleic acid ester include ethylene glycol dimaleate, triethylene glycol dimaleate, pentaerythritol dimaleate and sorbitol tetramaleate. Furthermore, a mixture of the above-mentioned ester monomers can also be mentioned. Specific examples of the amide monomer of the aliphatic polyvalent amine compound and the unsaturated carboxylic acid include methylenebis-acrylamide, methylenebis-methacrylamide, 1,6-hexamethylenebis-acrylamide, 1,6-hexamethylenebis. −
Methacrylamide, diethylenetriamine tris acrylamide, xylylene bis acrylamide, xylylene bis methacrylamide and the like.

Another example is Japanese Examined Patent Publication No. 48-417.
In the polyisocyanate compound having two or more isocyanate groups in one molecule described in JP-A-08,
Examples thereof include vinyl urethane compounds having two or more polymerizable vinyl groups in one molecule to which a vinyl monomer having a hydroxyl group represented by the following general formula (A) is added.

CH ₂ ═C (R ³ ) COOCH ₂ CH (R ⁴ ) OH (A) (wherein R ³ and R ⁴ represent H or CH ₃ ).

Further, urethane acrylates as described in JP-A-51-37193 and JP-B-2-32293, JP-A-48-64183 and JP-B-49-
Examples thereof include polyfunctional acrylates and methacrylates such as polyester acrylates and epoxy acrylates obtained by reacting an epoxy resin with (meth) acrylic acid as described in Japanese Patent Publication No. 43191 and Japanese Patent Publication No. 52-30490. . Furthermore, the Japan Adhesive Association Magazine Vol. Two
0, No. The materials introduced as photocurable monomers and oligomers on pages 7,300 to 308 (1984) can also be used.

In addition, the α-hetero type monomer having the structure represented by the general formula (I) described in JP-A 2001-92127 can also be preferably used. Specific examples of the α-hetero type monomer are shown below.

[0062]

[Table 1]

[0063]

[Table 2]

[0064]

[Table 3]

[0065]

[Table 4]

[0066]

[Table 5]

[0067]

[Table 6]

[0068]

[Table 7]

[0069]

[Table 8]

[0070]

[Table 9]

[0071]

[Table 10]

[0072]

[Table 11]

[0073]

[Table 12]

[0074]

[Table 13]

[0075]

[Table 14]

[0076]

[Table 15]

[0077]

[Table 16]

[0078]

[Chemical 7]

[0079]

[Chemical 8]

[0080]

[Chemical 9]

[0081]

[Chemical 10]

[0082]

[Chemical 11]

[0083]

[Chemical 12]

[0084]

[Chemical 13]

[0085]

[Chemical 14]

The amount of these ethylenically unsaturated compounds used is 5 to 80% by weight, preferably 3% by weight of the total components of the photosensitive layer.
It is used in the range of 0 to 70% by weight.

The polymer binder used in the photosensitive layer of the photosensitive lithographic printing plate of the present invention is not only used as a film-forming agent for the composition, but also needs to be dissolved in an alkali developing solution, so that it can be dissolved in alkaline water. Organic high molecular weight polymers that are soluble or swellable are used. The organic high molecular polymer can be developed in water by using, for example, a water-soluble organic high molecular polymer. As such an organic polymer, an addition polymer having a carboxylic acid group in its side chain, for example, JP-A-59-4
4615, Japanese Patent Publication No. 54-34327, Japanese Patent Publication No. 58-
No. 12577, Japanese Examined Patent Publication No. 54-25957, and Japanese Unexamined Patent Publication No. 54
-92723, JP-A-59-53836, JP-A-5-
9-71048, that is, methacrylic acid copolymer, acrylic acid copolymer, itaconic acid copolymer, crotonic acid copolymer, maleic acid copolymer,
There are partially esterified maleic acid copolymers and the like.

Similarly, there is an acidic cellulose derivative having a carboxylic acid group in its side chain. In addition to these, a product obtained by adding a cyclic acid anhydride to an addition polymer having a hydroxyl group is useful. In particular, among these, [benzyl (meth) acrylate / (meth) acrylic acid / another addition-polymerizable vinyl monomer if necessary] copolymer and [allyl (meth) acrylate / (meth) acrylic acid / optionally And other addition-polymerizable vinyl monomers] copolymers are preferred.
In addition, polyvinylpyrrolidone, polyethylene oxide and the like are useful as the water-soluble organic polymer. Further, alcohol-soluble polyamide, polyether of 2,2-bis- (4-hydroxyphenyl) -propane and epichlorohydrin, etc. are also useful for increasing the strength of the cured film. In addition, Japanese Patent Publication 7-120040 and Japanese Patent Publication 7-120
041, 7-120042, 8-12
424, JP-A-63-287944, JP-A-63-
287947, JP-A-1-271741, JP-A-1
The polyurethane resin described in 1-352169 is also useful for the application of the present invention.

These high molecular weight polymers can improve the strength of the cured film by introducing a radical reactive group into the side chain. The functional group capable of addition polymerization reaction is an ethylenically unsaturated bond group, an amino group, an epoxy group or the like, and the functional group capable of becoming a radical by light irradiation is a mercapto group, a thiol group, a halogen atom, a triazine structure, an onium salt structure. Examples of the polar group include a carboxyl group and an imide group. The functional group capable of undergoing the addition polymerization reaction is particularly preferably an ethylenically unsaturated bond group such as an acrylic group, a methacrylic group, an allyl group and a styryl group, but also an amino group, a hydroxy group, a phosphonic acid group, a phosphoric acid group, a carbamoyl group. A functional group selected from an isocyanate group, an ureido group, a ureylene group, a sulfonic acid group and an ammonio group is also useful.

In order to maintain the developability of the composition, the polymer binder of the present invention preferably has an appropriate molecular weight and acid value, and has a weight average molecular weight of 5,000 to 300,000 and an acid value of 2.
A high molecular weight polymer of 0 to 200 mg KOH / g is effectively used. These organic high molecular weight polymers can be mixed in arbitrary amounts in the entire composition. However, when it exceeds 90% by weight, favorable results are not obtained in terms of the strength of the formed image. Preferably 10 to 90%, more preferably 3
It is 0 to 80%. The weight ratio of the photopolymerizable ethylenically unsaturated compound and the organic polymer is 1/9 to 9/1.
The range is preferably More preferable range is 2/8
8/8, and more preferably 3/7 to 7/3.

Further, a colorant is added for the purpose of coloring the photosensitive layer. As the colorant, for example, a phthalocyanine-based pigment (CI Pigment Blue 15: 3,
15: 4, 15: 6, etc.), azo pigments, carbon black, pigments such as titanium oxide, ethyl violet, crystal violet, azo dyes, anthraquinone dyes, and cyanine dyes. Among these, metal phthalocyanine pigments are most preferable in terms of visibility and stability. The amount of dyes and pigments added is about 0.5% of the total composition.
About 20% is preferred.

In the present invention, in addition to the above basic components, a small amount of thermal polymerization is prohibited in order to prevent unnecessary thermal polymerization of the polymerizable ethylenically unsaturated compound during the production or storage of the photosensitive composition. It is desirable to add agents. Suitable thermal polymerization inhibitors include haloid quinone, p-
Methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4'-thiobis (3-methyl-6-t-butylphenol), 2,2'-methylenebis (4-methyl) −
6-t-butylphenol), N-nitrosophenylhydroxylamine primary cerium salt, N-nitrosophenylhydroxylamine aluminum salt and the like.
The addition amount of the thermal polymerization inhibitor is preferably about 0.01% to about 5% based on the weight of the entire composition. Further, if necessary, a higher fatty acid derivative such as behenic acid or behenic acid amide may be added to prevent polymerization inhibition by oxygen, and may be unevenly distributed on the surface of the photosensitive layer during the drying process after coating. . The amount of the higher fatty acid derivative added is about 0.5% to about 1 of the total composition.
0% is preferable. In addition, additives such as an inorganic filler and a plasticizer such as dioctyl phthalate, dimethyl phthalate and tricresyl phosphate may be added to improve the physical properties of the cured film. These are added in an amount of 10 of the total composition.
% Or less is preferable.

When the photosensitive layer composition of the photosensitive lithographic printing plate of the present invention is coated on the support described below, it is dissolved in various organic solvents before use. As the solvent used here,
Acetone, methyl ethyl ketone, cyclohexane, ethyl acetate, ethylene dichloride, tetrahydrofuran,
Toluene, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, acetylacetone, cyclohexanone, diacetone alcohol, ethylene glycol monomethyl ether acetate, ethylene glycol ethyl ether acetate, ethylene glycol Monoisopropyl ether, ethylene glycol monobutyl ether acetate, 3-
Methoxypropanol, methoxymethoxyethanol,
Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate-3-methoxypropyl acetate, N, N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, lactic acid Examples include methyl and ethyl lactate. These solvents can be used alone or as a mixture. The concentration of the solid content in the coating solution is preferably 1 to 50% by weight.

A surfactant can be added to the photopolymerizable composition in the photosensitive layer of the photosensitive lithographic printing plate of the present invention in order to improve the quality of the coated surface. The coating amount is suitably ranges from about 0.1 g / m ² ~ about 10 g / m ² in weight after drying. It is more preferably 0.3 to 5 g / m ² . More preferably, it is 0.5 to 3 g / m ² .

Further, usually, an oxygen blocking protective layer is provided on the photosensitive layer in order to prevent the polymerization inhibition of oxygen. Examples of the water-soluble vinyl polymer contained in the oxygen barrier protective layer include polyvinyl alcohol, and partial esters, ethers, and acetals thereof, or a substantial amount of an unsubstituted vinyl alcohol unit such that they have the necessary water solubility. And its copolymers containing Examples of polyvinyl alcohol include those that are 71 to 100% hydrolyzed and have a degree of polymerization of 300 to 2400. Specifically, PVA-10 manufactured by Kuraray Co., Ltd.
5, PVA-110, PVA-117, PVA-117
H, PVA-120, PVA-124, PVA-124
H, PVA-CS, PVA-CST, PVA-HC, P
VA-203, PVA-204, PVA-205, PV
A-210, PVA-217, PVA-220, PVA
-224, PVA-217EE, PVA-220, PV
A-224, PVA-217EE, PVA-217E,
PVA-220E, PVA-224E, PVA-40
5, PVA-420, PVA-613, L-8 and the like. Examples of the above-mentioned copolymers include polyvinyl acetate chloroacetate or propionate which is 88 to 100% hydrolyzed, polyvinyl formal and polyvinyl acetal, and copolymers thereof.
Other useful polymers include polyvinylpyrrolidone, gelatin and gum arabic, which may be used alone or in combination.

Pure water is preferably used as a solvent for coating the oxygen-blocking protective layer in the photosensitive lithographic printing plate of the present invention, but alcohols such as methanol and ethanol, ketones such as acetone and methyl ethyl ketone are purified water. May be mixed with. The concentration of the solid content in the coating solution is preferably 1 to 20% by weight. Known additives such as a surfactant for improving the coating property and a water-soluble plasticizer for improving the physical properties of the film may be added to the oxygen-blocking protective layer of the present invention. Examples of the water-soluble plasticizer include propionamide, cyclohexanediol, glycerin, sorbitol and the like. Further, a water-soluble (meth) acrylic polymer or the like may be added. The coating amount is about 0.1 g / m ² to about 15 g / m ² after drying.
The range is appropriate. More preferably 1.0 g / m ² ~
It is about 5.0 g / m ² .

Next, the support of the photosensitive lithographic printing plate of the present invention will be described. The aluminum support used in the present invention is dimensionally stable aluminum or its alloy (for example, silicon, copper, manganese, magnesium, chromium,
It means a plastic film or paper on which zinc, lead, bismuth, an alloy with nickel), aluminum, or an aluminum alloy is laminated or vapor-deposited, and the thickness thereof is usually about 0.05 mm to 1 mm. Further, the composite sheet described in JP-A-48-18327 can also be used.

The aluminum support of the present invention is appropriately subjected to the substrate surface treatment described later. (Graining treatment) Japanese Patent Laid-Open No. 56-2
Mechanical graining, chemical etching, electrolytic graining, etc. as disclosed in 8893. Furthermore, an electrochemical graining method of electrochemically graining in hydrochloric acid or nitric acid electrolyte, a wire brush grain method of scratching the aluminum surface with a metal wire, and a ball grain method of graining the aluminum surface with a polishing ball and an abrasive A mechanical graining method such as a brush grain method in which the surface is grained with a nylon brush and an abrasive can be used, and the above graining methods can be used alone or in combination. Among them, the method for producing the surface roughness usefully used in the present invention is an electrochemical method of chemically graining in a hydrochloric acid or nitric acid electrolytic solution, and a suitable current density is 100 C / dm ^{2 to} 400 C. The range is / dm ² . More specifically, in an electrolytic solution containing 0.1 to 50% hydrochloric acid or nitric acid, the temperature is 20 to 100 ° C., and the time is 1 second to 3
0 minutes, it is preferable to perform the electrolysis at a current density of ^{100C / dm 2 ~400C / dm 2} .

The grained aluminum support is chemically etched with an acid or an alkali. When an acid is used as an etching agent, it takes time to destroy the fine structure, which is disadvantageous in industrially applying the present invention, but it can be improved by using an alkali as the etching agent. Alkali agents preferably used in the present invention include caustic soda, sodium carbonate, sodium aluminate, sodium metasilicate, sodium phosphate, potassium hydroxide, lithium hydroxide, etc., and the preferred ranges of concentration and temperature are 1 to 50, respectively. %, 20-10
The conditions are preferably 0 ° C. and the amount of Al dissolved is 5 to 20 g / m ³ . After etching, pickling is performed to remove stains (smut) remaining on the surface.
As the acid used, nitric acid, sulfuric acid, phosphoric acid, chromic acid, hydrofluoric acid, borofluoric acid or the like is used. Particularly, as a method for removing smut after the electrochemical graining treatment, it is preferable to contact with 15 to 65% by weight of sulfuric acid at a temperature of 50 to 90 ° C. as described in JP-A-53-12739. And the alkali etching method described in JP-B-48-28123.
The surface roughness (Ra) of the Al support effectively used in the present invention is 0.3 to 0.7 μm.

(Anodizing Treatment) The aluminum support treated as described above is further subjected to anodizing treatment. The anodizing treatment can be performed by a method conventionally used in this field. Specifically, sulfuric acid, phosphoric acid,
Chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, etc. or a combination of two or more of these can be used to form an anodized film on the surface of an aluminum support by applying a direct current or an alternating current to aluminum in an aqueous solution or a non-aqueous solution. . The conditions of the anodizing treatment vary variously depending on the electrolytic solution used, and therefore cannot be determined unconditionally,
Generally, the electrolyte concentration is 1 to 80%, and the liquid temperature is 5 to 70.
C, current density 0.5-60 amps / dm ² , voltage 1-
A range of 100 V and electrolysis time of 10 to 100 seconds is suitable.

Among these anodizing treatments, particularly described in British Patent No. 1,412,768,
A method of anodizing in sulfuric acid at a high current density and a method of anodizing phosphoric acid as an electrolytic bath described in US Pat. No. 3,511,661 are preferable. In the present invention, the anodized film is preferably from ^{1~10g / m 2, 1g / m} 2 plate to easily enter the wound is not more than, 10 g / m ² or more is great power is required for the production , Economically disadvantageous. Preferably 1.5 to 7 g /
m ² . More preferably, it is ² to 5 g / m ² .

Further, in the present invention, after the graining treatment and the anodic oxidation, the aluminum support may be subjected to the pore-sealing treatment. Such sealing treatment is performed by dipping the substrate in hot water and a hot aqueous solution containing an inorganic salt or an organic salt, a steam bath, or the like. Further, the aluminum support of the present invention may be subjected to a treatment other than the silicate treatment with an alkali metal silicate, for example, a surface treatment such as a dipping treatment in an aqueous solution of potassium fluorozirconate, a phosphate or the like. A photosensitive lithographic printing plate of the present invention is prepared by forming a photosensitive layer made of the photopolymerizable composition on an aluminum support that has been surface-treated as described above.
An organic or inorganic undercoat layer may be provided, if necessary, before coating the photosensitive layer.

The photosensitive layer in the photosensitive lithographic printing plate of the present invention is formed, for example, with a carbon arc lamp, a high pressure mercury lamp, a xenon lamp, a metal halide lamp, a fluorescent lamp, a tungsten lamp, a halogen lamp, a helium cadmium laser, an argon ion laser, an FD.・ YAG laser, helium neon laser, semiconductor laser (3
An image can be formed on the surface of the aluminum plate support by imagewise exposure with a conventionally known actinic ray (50 nm to 600 nm) and the like, followed by development treatment. Between the image exposure and the development, a heating process for 1 second and 5 minutes at a temperature of 50 ° C. to 150 ° C. may be provided for the purpose of increasing the curing rate of the photopolymerizable photosensitive layer.

As described above, an overcoat layer having an oxygen-blocking property is usually provided on the photosensitive layer of the photosensitive lithographic printing plate of the invention, and the developer of the invention is used to A method is known in which the removal of the overcoat layer and the unexposed portion of the photosensitive layer are performed simultaneously, or the method of first removing the overcoat layer with water or warm water and then removing the photosensitive layer in the unexposed area by development. There is. These water or warm water may contain an antiseptic agent described in JP-A-10-10754 and an organic solvent described in JP-A-8-278636.

The development of the photosensitive lithographic printing plate according to the present invention with the above-mentioned developing solution is carried out by a conventional method at a temperature of 0 to 60 ° C., preferably about 15 to 40 ° C., for example, by exposing the photosensitive lithographic printing plate. It is carried out by immersing it in a developing solution and rubbing it with a brush. Further, when the development processing is performed using an automatic developing machine, the developing solution becomes fatigued depending on the processing amount, so that the processing capacity may be recovered by using a replenishing solution or a fresh developing solution. The photosensitive lithographic printing plate thus developed is washed with water, surface-active as described in JP-A-54-8002, 55-115045, 59-58431 and the like. It is post-treated with a rinse solution containing an agent and the like, and a desensitizing solution containing gum arabic and a starch derivative. Various combinations of these treatments can be used in the post-treatment of the photosensitive lithographic printing plate of the present invention.

The printing plate obtained by the above-mentioned treatment can be improved in printing durability by a post-exposure treatment or a heating treatment such as burning according to the method described in JP-A-2000-89478. The planographic printing plate obtained by such treatment is set on an offset printing machine and used for printing a large number of sheets.

[0107]

The present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited by these. [Example of support] (Support 1: Anodized aluminum support) Thickness 0.3
An aluminum plate of 0 mm in material 1S was used with a No. 8 nylon brush and an 800 mesh pumicestone water suspension, the surface of which was grained and then thoroughly washed with water. After dipping in 10% sodium hydroxide at 70 ° C for 60 seconds for etching, washing with running water, neutralization washing with 20% HNO ₃ ,
Washed with water. This was subjected to electrolytic surface-roughening treatment in an aqueous 1% nitric acid solution under the condition of V _A = 12.7 V in an aqueous 1% nitric acid solution at an anode electricity of 300 coulomb / dm ² .
When the surface roughness was measured, it was 0.45 μm (Ra indication). Then, it is immersed in a 30% aqueous solution of H ₂ SO _{4 and} desmutted at 55 ° C for 2 minutes, and then 33 ° C.
When a cathode was placed on a grained surface in a 20% H ₂ SO ₄ aqueous solution and anodized at a current density of 5 A / dm ² for 50 seconds, the thickness was 2.7 g / m ² . This was used as a support 1.

(Support 2) The following undercoat liquid composition 1 for surface treatment was applied to Support 1 so that the P content was about 0.05 g / m ^2, and dried at 100 ° C. for 1 minute. Support 2 was used.

[0109]   <Liquid composition 1 for undercoat>     Phenylphosphonic acid 2 parts by weight     800 parts by weight of methanol     50 parts by weight of water

(Support 3) A support 1 was coated with the following undercoating liquid composition 2 for surface treatment so that the amount of Si was about 0.001 g / m ^2, and dried at 100 ° C. for 1 minute. The support 3 was used.

<Liquid composition for undercoating 2> The following components were mixed and stirred, and an exotherm was observed after about 5 minutes, and after reacting for 60 minutes, the contents were transferred to another container and further 30,000 parts by weight of methanol was added. Liquid composition 2 was added.

[0112]     Unichemical Co., Ltd. Hosmer PE 20 parts by weight     130 parts by weight of methanol     20 parts by weight of water     Paratoluenesulfonic acid 5 parts by weight     Tetraethoxysilane 50 parts by weight     3-methacryloxypropyltriethoxysilane 50 parts by weight

[Example of Sensitive Material] A dry coating weight of 1.5 g / m ^{2 of the} photopolymerizable composition having the following composition was applied onto the above-mentioned supports 1 to 3.
And was dried at 100 ° C. for 1 minute to form a photosensitive layer. Then, 3 wt% of polyvinyl alcohol (saponification degree: 98 mol%, polymerization degree: 500) was formed on the photosensitive layer.
Was applied so that the dry coating weight would be 2.5 g / m ^2, and dried at 120 ° C. for 3 minutes to obtain a photosensitive lithographic printing plate (sensitive material).

[0114] (Photosensitive layer coating liquid (photopolymerizable composition): Details are shown in Table 7 below)   Ethylenically unsaturated bond-containing compound (A) 1.5 parts by weight   Linear organic high molecular polymer (B) 2.0 parts by weight   Sensitizer (C) a part by weight   Photoinitiator (D) b parts by weight   Additive (S) 0.50 parts by weight   Fluorine-based surfactant 0.03 parts by weight   (Mechafuck F-177: manufactured by Dainippon Ink and Chemicals, Inc.)   Thermal polymerization inhibitor 0.01 parts by weight   (N-nitrosohydroxylamine aluminum salt)   Colorant (F) 0.30 parts by weight   Methyl ethyl ketone 30.0 parts by weight   Propylene glycol monomethyl ether 30.0 parts by weight

[0115]

[Table 17]

The ethylenically unsaturated bond-containing compound (A), linear organic high molecular polymer (B), sensitizer (C), photoinitiator (D), additive used in the photosensitive layer coating liquid. (S)
The colorant (F) is shown below.

[0117]

[Chemical 15]

[0118]

[Chemical 16]

This photosensitive lithographic printing plate was irradiated with an FD / YAG laser (CSI plate jet 4) at 100 μJ /
After exposing the solid image and the dot image of 1 to 99% (in 1% increments) by scanning exposure under the condition of 175 lines / inch at 4000 dpi with the exposure amount of cm ² , the developer 1 and the finishing gum solution FP -2W (manufactured by Fuji Photo Film Co., Ltd.) was used for standard processing with an automatic processor (LP-850P2 manufactured by Fuji Photo Film Co., Ltd.). The preheating condition is that the temperature reached to the printing plate is 1.
00 ℃, developer temperature is 30 ℃, immersion time in developer is about 1
It was 5 seconds. Developer 1 has the following composition and pH is 2
It was 11.5 at 5 ° C.

[0120] (Composition of developer 1)   Potassium hydroxide 0.25g   Polyoxyethylene phenyl ether (n = 13) 5.0 g   CHIREST 400 (chelating agent) 0.1 g   Compound 1 below 1.75 g   Water 92.9 g

(Developers 2-5) The planographic printing plate was prepared in the same manner as in Example 1 except that the developer of Example 1 was changed to the developer shown below.

[0122] (Composition of developer 2)   Potassium hydroxide 0.15g   Compound 2 15.0 g below   The following compound 4 5.0 g   CHIREST 400 (chelating agent) 0.1 g   79.75g water The pH of this developer was 11.4 at 25 ° C.

[0123] (Composition of developer 3)   Potassium hydroxide 0.15g   The following compound 1 1.5 g   The following compound 3 4.0 g   Polyoxyethylene naphthyl ether (n = 13) 3.0 g   Triethanolamine 2.5 g   90.35 g of water The pH of this developer was 10.9 at 25 ° C.

[0124] (Composition of developer 4)   1K potassium silicate 3.0 g   Potassium hydroxide 1.5 g   Compound 2 10.0 g below   Lipomin LA (20% aqueous solution, manufactured by Lion Corporation) 30.0 g   CHIREST 400 (chelating agent) 0.1 g   Water 55.4 g The pH of this developer was 11.9 at 25 ° C.

[0125] (Composition of developer 5)   1K potassium silicate 3.0 g   Potassium hydroxide 1.5 g   The following compound 3 16.0 g   Polyoxyethylene phenyl ether (n = 9) 5.5 g   CHIREST 400 (chelating agent) 0.1 g   Benzyl alcohol 2.0 g   Water 71.9 g The pH of this developing solution was 12.7 at 25 ° C.

[0126]

[Chemical 17]

[Comparative Developer 1] A composition obtained by removing Compound 1 from Developer 1 was used as Comparative Developer 1 (pH 11.5). [Comparative Developer 2] A composition obtained by removing Compound 2 from Developer 4 was used as Comparative Developer 2 (pH 11.9). [Comparative Developer 3] A developer was prepared by changing the amount of potassium hydroxide added to 2.5 g based on Developer 1. The pH of this developing solution was 13.2. This was designated as Comparative Developer 3.

The lithographic printing plates obtained by the plate making methods of Examples 1 to 14 and Comparative Examples 1 to 3 described above had photosensitivity, developability,
The printing durability, print stains, and development residue were evaluated.
The developability was judged by visually observing the plate surface after the developing treatment and by the presence or absence of the photosensitive layer residual film and the degree of the residual film. Printing durability is man
Printing was performed using GEOS G ink (N) manufactured by Dainippon Ink and Co., Ltd. with an R201 type printer manufactured by Roland Co., Ltd., and the number of printed sheets in which 3% of halftone dots caused the plate jump was evaluated. The printing stain resistance was evaluated using a diamond IF2 type printing machine manufactured by Mitsubishi Heavy Industries, Ltd., using GEOS G Red (S) manufactured by Dainippon Ink and visually evaluating the ink stain on the non-image area. To evaluate the development residue, the lithographic printing plate was developed in a developer (1 liter) and left for 1 month, and the presence or absence of precipitated development residue was visually observed.

(Evaluation of Photosensitivity) On the obtained light-sensitive material, Fuji Step Guide (ΔD =) manufactured by Fuji Photo Film Co., Ltd.
A gray scale whose transmission optical density changes discontinuously at 0.15) was brought into close contact, and exposure was performed using a xenon lamp that passed through an optical filter so that the exposure energy was known. As the optical filter, Kenko BP-53 which can be exposed with monochromatic light of 532 nm was used for the purpose of estimating the exposure suitability for a short-wave semiconductor laser. Then, it was immersed in a developer having the following composition at 25 ° C. for 10 seconds, developed, and an ink was applied to the image area, and the sensitivity (clear sensitivity) was calculated from the maximum number of steps at which the image was completely removed. Here, the clear sensitivity represents the minimum energy required for image formation, and the lower the value, the higher the sensitivity. The results are shown in Table 8 below.

[0130]

[Table 18]

As is apparent from Table-8, the lithographic printing plates of the respective examples according to the present invention gave satisfactory results, but the lithographic printing plates of the comparative examples were unsatisfactory in some evaluation results. Met.

[0132]

As described above, the plate-making method of the lithographic printing plate of the present invention is a photopolymerization containing a compound having an ethylenically unsaturated double bond, a polymer binder, a photopolymerization initiator and a colorant. By using a developing solution containing a compound that has a relatively low pH and is capable of coordinating with a metal, for a photosensitive lithographic printing plate having a photosensitive layer made of a photosensitive composition of
It is possible to produce a lithographic printing plate excellent in print stain resistance and printing durability without generating development dust. Also, p of the developing solution
Since H is relatively low, it is preferable in terms of safety, and the effect of improving the environment of waste developer can be improved.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03F 7/004 505 G03F 7/004 505 7/027 7/027 7/029 7/029 7/038 7 / 038 F-term (reference) 2H025 AA01 AA04 AA12 AB03 AC01 AD01 BC31 BC51 CA39 CC12 DA18 FA03 FA16 2H096 AA07 AA08 BA05 BA06 BA20 CA20 EA02 GA12 GA13 4J011 CA05 CB00 PA49 PB25 PC02 PC08 QA03 QA13 QA15 QA19 QA22 QA23 QA26 QA27 QA32 QA34 QA37 QA38 QA39 QA40 QA45 QA46 QB01 QB02 QB06 QB14 QB17 QB19 QB24 SA85 UA01 UA02 VA01 WA01

Claims (3)

[Claims] 1. A photosensitive layer comprising a photopolymerizable photosensitive composition containing a compound having an ethylenically unsaturated double bond, a polymer binder, a photopolymerization initiator and a colorant on an aluminum support. The photosensitive lithographic printing plate contains a compound capable of coordinating with a metal after imagewise exposure, and has a pH of 10.0 to
A method of making a lithographic printing plate, which comprises developing with a developing solution of 12.8. 2. The method of making a lithographic printing plate according to claim 1, wherein the photopolymerization initiator is a titanocene-based photopolymerization initiator. 3. The method of making a lithographic printing plate according to claim 1, wherein the colorant is a metal phthalocyanine pigment.