JP3318022B2 - Method for producing photosensitive resin composition and lithographic printing plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a photosensitive resin composition and a method for producing a lithographic printing plate, and more particularly to a negative photosensitive resin composition and a method for producing the lithographic printing plate. More specifically, the present invention relates to a photosensitive resin composition comprising a negative photosensitive compound and an organic polymer binder having excellent abrasion resistance and aqueous alkali developability, and further relates to a photosensitive layer comprising the photosensitive resin composition. The present invention relates to a method for producing a lithographic printing plate by imagewise exposing a photosensitive lithographic printing plate having the formula (I), followed by development with an aqueous alkaline developer substantially free of an organic solvent.

[0002]

2. Description of the Related Art A photosensitive lithographic printing plate is roughly classified into a negative type in which an exposed portion becomes insoluble in a developing solution by light irradiation and a positive type in which the exposed portion becomes soluble in a developing solution by light irradiation.

A negative-working photosensitive lithographic printing plate is generally obtained by coating a photosensitive composition containing a negative-working photosensitive compound on a support such as a roughened aluminum plate. Activated light such as ultraviolet rays is irradiated through such as to polymerize or crosslink the irradiated part to make it insoluble in the developing solution, and the non-irradiated part is eluted in the developing solution, and the oily ink repels water, respectively. And a non-image portion that receives water and repels oil-based ink, and is a lithographic printing plate. This lithographic printing plate is printed by an offset printing machine utilizing the lipophilicity of the image area and the hydrophilicity of the non-image area.

In this case, as the negative type photosensitive compound, (1) a photosensitive diazonium compound, (2) a combination of a compound having an ethylenically unsaturated group and a photopolymerization initiator, (3) Examples include a combination of a photosensitive diazonium compound, a compound having an ethylenically unsaturated group, and a photopolymerization initiator.

The photosensitive diazonium compounds include 4-
A diazo resin represented by a condensate of diazodiphenylamine and formaldehyde is generally used.

The composition of the photosensitive layer of a photosensitive lithographic printing plate using a diazo resin is disclosed, for example, in US Pat. No. 2,714,06.
No. 6, classified into a diazo resin alone, for example, a mixture of an organic polymer binder and a diazo resin as described in JP-A-50-30604. However, the diazo resin alone has poor abrasion resistance, does not provide sufficient printing durability,
Further, due to insufficient oil sensitivity, many photosensitive lithographic printing plates have recently been composed of an organic polymer binder and a diazo resin.

[0007] Such a photosensitive layer is disclosed in
As described in Japanese Patent No. 30604, a so-called alkali developing type in which an unexposed portion is removed (developed) by an aqueous alkali developing solution and a so-called solvent developing type in which an unexposed portion is removed by an organic solvent-based developing solution are known. However, from the viewpoint of occupational safety and health, attention has been paid to the alkali developing type, which is determined mainly by the properties of the binder. As a method for imparting alkali developability to a binder, as described in JP-A-50-30634, a carboxylic acid-containing monomer may be copolymerized, or US Pat. No. 2,861,058. As described in the specification, there is a method in which a carboxylic acid is introduced into a polymer by reacting a hydroxyl group of polyvinyl alcohol with a cyclic anhydride such as phthalic anhydride. However, the photosensitive lithographic printing plate containing such a binder in the photosensitive layer was poor in abrasion resistance, and only a lithographic printing plate having a low printing durability was obtained. On the other hand, polyvinyl acetal forms a tough film and has abrasion resistance, but has the drawback that only organic solvent development type photosensitive lithographic printing plates can be obtained.

Further, many attempts have been made to use the photopolymerizable composition as a photosensitive image-forming layer of a negative-working photosensitive lithographic printing plate, such as a polymer as a binder as disclosed in JP-B-46-32714. A basic composition comprising a compound having an ethylenically unsaturated group and a photopolymerization initiator, an unsaturated double bond is introduced into a polymer as a binder as disclosed in JP-B-49-34041,
A composition having improved curing efficiency, a novel photopolymerization initiator as disclosed in JP-B-48-38403 and JP-B-53-27605 and British Patent No. 1,388,492. The composition and the like used are known and some are practically used, but any photosensitive composition
The sensitivity is greatly affected by the surface temperature of the photosensitive lithographic printing plate at the time of image exposure, and the polymerization lithographic printing plate is strongly affected by polymerization inhibition by oxygen at the time of image exposure.

On the other hand, when developing these negative-working photosensitive lithographic printing plates after exposure, examples of aqueous alkaline developer compositions used include benzyl alcohol and benzyl alcohol described in JP-A-51-77401. A developer composition comprising an anionic surfactant, an alkali agent and water;
JP-A-55-155355 discloses a developer composition comprising an aqueous solution containing benzyl alcohol, an anionic surfactant and a water-soluble sulfite described in JP-A-3-44202.
At room temperature is 1
A developer composition containing 0% by weight or less of an organic solvent, an alkali agent, and water is used.

[0010] Each of these contains an organic solvent in the developer composition. However, the organic solvent generally has toxicity and odor, has a risk of fire, and has many disadvantages such as being subject to BOD regulations even in the waste liquid, and the cost is high.

[0011] Examples of the alkali developer compositions substantially free of these organic solvents include the developer compositions described in JP-A-59-84241. However, these developer compositions are used for developing a positive-type photosensitive lithographic printing plate containing a о-naphthoquinonediazide compound as a photosensitive compound, and the developer compositions containing substantially no organic solvent are used. When the negative photosensitive lithographic printing plate described above is developed using the product, development cannot be carried out without forming a residual film, and further, undeveloped portions are yellowed and the like, and proper developability cannot be obtained. There was a problem.

Therefore, the negative and positive type photosensitive lithographic printing plates generally use a dedicated developer, respectively, and a large number of these two types of photosensitive lithographic printing plates are simultaneously processed. In such a case, two automatic developing machines and the like are required, and there is a problem in terms of equipment cost, equipment, and the like, in terms of economic efficiency.

In the case where the two photosensitive lithographic printing plates are to be commonly processed by one automatic developing machine,
Depending on the type of photosensitive lithographic printing plate to be processed,
The developer had to be replaced, which was extremely wasteful in terms of working efficiency and economy.

In order to solve such a problem, a method of developing both photosensitive lithographic printing plates with the same developing solution has been proposed. However, in practice, good results have not yet been obtained. The following can be considered as a reason for this. That is, in general, a developer for a positive-type lithographic printing plate having a photosensitive layer composed of an o-quinonediazide compound and an alkali-soluble resin, etc., has a pH of 1 mainly containing silicate as a main component.
When developing a non-exposed part of a negative type lithographic printing plate composed of a water-insoluble diazo resin and an alkali-soluble resin using this developing solution, the developer cannot be developed at all, or the development residue remains. There is a problem that the printing is easy and stains easily occur when printing. In addition, when an alkali-soluble resin such as a high acid value acrylic resin or a styrene-maleic acid copolymer is used, development can be performed with a developer for a positive type lithographic printing plate. There have been problems that polymer sludge is generated and printing durability is extremely reduced. Conversely, when developing the exposed part of the positive type lithographic printing plate with the developing solution of the negative type lithographic printing plate, similarly, the development cannot be performed well, the residual film remains, and the printing becomes dirty, or In the negative-type developer, the photosensitive layer of the positive-type lithographic printing plate is easily immersed by the solvent contained in the negative-type developer, so that the development tolerance is reduced, and the oil sensitivity and printing durability are reduced. There were problems such as lowering.

The expression "substantially contains no organic solvent" means that the organic solvent is not contained to such an extent that it causes inconvenience in view of the aforementioned environmental hygiene, safety and workability. In the present invention, the ratio of the substance in the composition is 2% by weight or less, preferably 1% by weight or less.

[0016]

An object of the present invention is to provide a photosensitive resin composition capable of obtaining a photosensitive layer having both excellent alkali developability and abrasion resistance. An object of the present invention is to provide a method for producing a lithographic printing plate that can develop a negative photosensitive lithographic printing plate with an aqueous alkaline developer substantially free of an organic solvent, and is toxic to the work, and has a hygienic nature such as odor. It is an object of the present invention to provide a method of manufacturing a lithographic printing plate free from problems such as safety, problems such as fire and gas explosion, and problems such as pollution caused by waste liquid.

Another problem to be solved by the present invention is that even when a large number of sheets are developed using an aqueous alkaline developer containing substantially no organic solvent, no sludge is generated and the printing durability is good. Another object of the present invention is to provide a method for producing a lithographic printing plate that provides a simple printing plate.

[0018]

In order to solve the above-mentioned problems, the present invention provides a polyester having a phenolic hydroxyl group, a modified product of the polyester, and an addition-polymerizable ethylene.
Compounds having an emission unsaturated group, and a photosensitive resin composition characterized by containing a photopolymerization initiator, generally described below
It has a phenolic hydroxyl group represented by the formulas (1) to (5)
Polycarboxylic acid containing dicarboxylic acid or derivative thereof
Pheno derived from an acid component and a polyhydric alcohol component
Or a polyester having a hydroxyl group
Containing a modified product, and a photosensitive diazonium compound,
In 1000 g of the polyester or modified polyester
The structural units represented by the general formulas (1) to (5)
A photosensitive resin composition, characterized by containing at least
And a photosensitive lithographic printing plate having a photosensitive layer comprising the composition, further comprising, after imagewise exposing the photosensitive lithographic printing plate, developing with an aqueous alkaline developer substantially free of an organic solvent. To provide a method for producing a lithographic printing plate.

The negative photosensitive compound used in the method for producing a photosensitive resin composition and a lithographic printing plate of the present invention includes:
A photosensitive compound selected from the following (A), (B) or (C) can be used.

(A) Photosensitive diazonium compound (B) Combination of a compound having an ethylenically unsaturated group and a photopolymerization initiator (C) Photosensitive diazonium compound, compound having an ethylenically unsaturated group and light Combination of polymerization initiator

The polyester having a phenolic hydroxyl group or a modified product of the polyester and other components used in the composition of the present invention and the method for producing the same, the method for producing the photosensitive composition used in the present invention, and the present invention The method for producing a lithographic printing plate will be described in detail.

The polyester or modified polyester having a phenolic hydroxyl group used in the present invention includes, for example, (A) a polycarboxylic acid component containing a dicarboxylic acid having a phenolic hydroxyl group or a derivative thereof, and a polyhydric alcohol component. Polyester having a phenolic hydroxyl group (B) A polyester having an alcoholic hydroxyl group obtained by reacting a polycarboxylic acid component containing a dicarboxylic acid having a phenolic hydroxyl group or a derivative thereof with a polyhydric alcohol component is produced. A compound having two or more functional groups in a molecule having higher reactivity to an alcoholic hydroxyl group than a phenolic hydroxyl group in a polyester [hereinafter referred to as a chain extender. ] And a modified polyester having a phenolic hydroxyl group.

The polyester having a phenolic hydroxyl group or the modified polyester may optionally have another bond which does not react with the phenolic hydroxyl group in the polyester chain,
For example, it may have urethane, amide, ureide, ether bond and the like.

Examples of the dicarboxylic acid having a phenolic hydroxyl group include dicarboxylic acids represented by the following general formulas (1) to (5).

[0025]

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[0026]

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[0027]

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[0028]

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[0029]

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(In the general formulas (1) to (5), R ₁ is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, and 1 to 4 carbon atoms.
Represents an alkoxyl group, a halogen atom or a nitro group,
R ₂ and R ₃ independently represent a hydrogen atom, a halogen atom, a nitro group or a cyano group, and X represents an alkylene group having 1 to 6 carbon atoms, an oxygen atom, a sulfur atom, a —CO— group, —SO
- group or -SO ₂ - represents a group, i represents an integer of 1 to 5, j is an integer of an integer, h and h 'are the independently 1~4 (5-i), f Represents 0 or 1, and g represents (4
-H) represents an integer, and g 'represents an integer of (4-h'). )

Examples of the above-mentioned dicarboxylic acids having a phenolic hydroxyl group and derivatives thereof include 4-hydroxybenzylidenemalonic acid, 3-hydroxybenzylidenemalonic acid, 3,4-dihydroxybenzylidenemalonic acid, and 4-hydroxy-3. -Methoxybenzylidenemalonic acid, 3-hydroxy-4-methoxybenzylidenemalonic acid, 4-hydroxy-3-nitrobenzylidenemalonic acid, 4-hydroxycinnamylidenemalonic acid, 3-hydroxycinnamylidenemalonic acid, 4-hydroxy- 3
-Methoxycinnamylidenemalonic acid, 4-hydroxy-
Hydroxymalonic acids such as 3-nitrocinnamylidenmalonic acid; 3-hydroxyphthalic acid, 4-hydroxyphthalic acid, 4-hydroxyisophthalic acid, 5-hydroxyisophthalic acid, hydroxyterephthalic acid, 3,6-dihydroxyphthalic acid, 2,5-dihydroxyisophthalic acid,
4,5-dihydroxyisophthalic acid, 2,3-dihydroxyterephthalic acid, 2,5-dihydroxyterephthalic acid, 2,4,6-trihydroxyisophthalic acid, 4,
5,6, -trihydroxyisophthalic acid, 4-hydroxy-5-nitroisophthalic acid, 4-hydroxy-5-chloroisophthalic acid, 3-hydroxy-6-methoxyphthalic acid, 2,4-dihydroxy-6-methylisophthalic acid Hydroxyphthalic acids such as acids; 3,3'-methylenebis (4-hydroxybenzoic acid), 4,6'-dihydroxy3,3'-biphenyldicarboxylic acid, 6,6'-dihydroxy-5,5'-dimethoxy- Hydroxybiphenyldicarboxylic acids such as 3,3′-biphenyldicarboxylic acid and 4,5-dihydroxy-2,4′-oxydibenzoic acid; 2-hydroxy-p-benzenediacetic acid, 2,5-dihydroxy-p-benzenedicarboxylic acid; Acetic acid, α, α′-dicyano-2,5-dihydroxy-p-benzenediacetic acid, α, α
α'-dinitro-2,5-dihydroxy-p-benzenediacetate, α, α'-dichloro-2,5-dihydroxy-
hydroxybenzene diacetates such as p-benzene diacetate and 5-hydroxy-m-phenylenedioxy (oxyacetic acid); dialkyl esters such as dimethyl ester and diethyl ester of the dicarboxylic acid; di (ethylene glycol) ester of the dicarboxylic acid And di (alkylene glycol) esters such as di (propylene glycol) ester.

In the production of polyester, other polycarboxylic acids or derivatives thereof can be used in combination with the above-mentioned dicarboxylic acids having a phenolic hydroxyl group or derivatives thereof. Examples of such compounds include succinic acid and adipine Acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, tetrabromophthalic acid, tetrachlorophthalic acid, 1,4-cyclohexanedicarboxylic acid, maleic acid, fumaric acid, Examples include polycarboxylic acids such as itaconic acid, carboxynorbornaneacetic acid, 5-sodium sulfoisophthalic acid, trimellitic acid and hymic acid, or anhydrides or ester derivatives thereof.

On the other hand, as the polyhydric alcohol component, various ones can be used without any particular limitation. For example, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, Aliphatic diols such as neopentyl glycol, 1,3-butylene glycol, 1,6-hexanediol, 2,2,4-trimethyl-1,3-pentanediol; glycerol α-monoallyl ether, trimethylolpropane Monoallyl ether, pentaerythritol diallyl ether, N,
Diols having a carbon-carbon unsaturated bond, such as N-diallyltartaramide diamide, 2-butene-1,4-diol and 2-butyne-1,4-diol; 1,4-bis-β-hydroxyethoxycyclohexane, cyclohexane Dimethanol, tricyclodecane dimethanol, hydrogenated bisphenol A, hydrogenated bisphenol F, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, ethylene oxide adduct of bisphenol F, propylene oxide adduct of bisphenol F , Ethylene oxide adduct of hydrogenated bisphenol A, propylene oxide adduct of hydrogenated bisphenol A, ethylene oxide adduct of tricyclodecane dimethanol, propylene oxide of tricyclodecane dimethanol Adducts, 5-norbornene-2,3
Alicyclic and aromatic cyclic diols such as dimethanol, 5-norbornene-2,2-dimethanol, hydroquinone dihydroxyethyl ether, p-xylylene glycol; 2,2-bis (hydroxymethyl) propionic acid;
2,2-bis (hydroxyethyl) propionic acid, 2,
2-bis (3-hydroxypropyl) propionic acid,
Diols having a carboxyl group such as 2,2-bis (2-hydroxypropyl) propionic acid and 2,2-bis (hydroxymethyl) -n-butyric acid; triols such as trimethylolpropane; tetraols such as pentaerythritol; Can be mentioned.

The synthesis of the polyester is usually carried out by means known in the art, for example, Seikagaku, "Koza Kogaku Kogaku ninsei, Polycondensation 9," Ogata, published by Kagaku Dojinsha, or JP-A-60-165646. Publication, US Pat. No. 3,622,3
A polyester having a phenolic hydroxyl group in a side chain can be easily produced by the method described in JP-A-20.

Examples of the chain extender usable in the method (B) include diaryl oxalate compounds, diaryl phthalate compounds, diaryl carbonate compounds,
And tetracarboxylic dianhydride.

As the diaryl oxalate compound,
The compound represented by the following general formula (6) and the diaryl phthalate compound include the compound represented by the following general formula (7) and the diaryl carbonate compound include the compound represented by the following general formula (8), respectively. be able to.

[0037]

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[0038]

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[0039]

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(In the general formulas (6) to (8), R ₁ and R ₂ each independently represent an aromatic hydrocarbon group which may have a substituent.)

As specific examples of R ₁ and R ₂ in each of the above general formulas,

[0042]

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(Wherein n represents an integer of 1 to 10;
Represents a halogen atom. ) And the like.

Examples of the tetracarboxylic dianhydride include compounds represented by the following general formula (9).

[0045]

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(In the above general formula (9), R is at least 2
Represents a tetravalent organic group containing carbon atoms. )

Examples of the tetracarboxylic dianhydride include pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 3,3 ′,
4,4'-diphenyltetracarboxylic dianhydride, 2,
3,6,7-naphthalenetetracarboxylic dianhydride,
1,4,5,8-naphthalenetetracarboxylic dianhydride, 4,4′-sulfonyldiphthalic dianhydride, 2,2
-Bis (3,4-dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, 4,4 ′-[3,3 ′-(alkylphosphoryldiphenylene) -bis (Iminocarbonyl)] aromatic tetracarboxylic dianhydrides such as diphthalic dianhydride, an adduct of hydroquinone diacetate and trimellitic anhydride, and an adduct of diacetyldiamine and trimellitic anhydride; 5- (2 , 5-dioxotetrahydrofuryl)-
3-Methyl-3-cyclohexene-1,2-dicarboxylic anhydride (trade name “Epiclon B-4400”, manufactured by Dainippon Ink and Chemicals, Incorporated), butane-1,2,3,4-
Examples thereof include aliphatic tetracarboxylic dianhydrides such as tetracarboxylic dianhydride and cyclopentanetetracarboxylic dianhydride.

The synthesis of the modified polyester having a phenolic hydroxyl group by the reaction between the polyester and a chain extender can be easily produced by, for example, the method described in JP-A-60-221748.

At this time, the structure and molecular weight of the (modified) polyester can be arbitrarily determined by changing the selection of the polyhydric carboxylic acid component, the polyhydric alcohol component and the chain extender and the synthesis conditions in various ways. However, in order to provide the intended use of the present invention, those having a weight-average molecular weight of 1,000 to 100,000 are preferable.
It is preferable to contain 0.5 mol or more of the structural unit represented by (5).

As the photosensitive diazonium compound, there is a diazo resin represented by a salt of a condensate of a diazodiarylamine and an active carbonyl compound, and a photosensitive, water-insoluble and organic solvent-soluble compound is preferable.

Particularly preferred diazo resins are 4-diazodiphenylamine, 4-diazo-3-methyldiphenylamine, 4-diazo-4'-methyldiphenylamine,
Diazo-3'-methyldiphenylamine, 4-diazo-
4'-methoxydiphenylamine, 4-diazo-3-methyl-4'-ethoxydiphenylamine, 4-diazo-
3-methoxydiphenylamine and the like and formaldehyde,
It is an organic acid salt or an inorganic acid salt of a condensate with paraformaldehyde, acetaldehyde, benzaldehyde, 4,4'-bis-methoxymethyldiphenyl ether and the like.

Examples of the organic acid include methanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, xylenesulfonic acid, mesitylenesulfonic acid, dodecylbenzenesulfonic acid, naphthalenesulfonic acid, propylnaphthalenesulfonic acid, 1-naphthol-5- Sulfonic acid, 2
-Nitrobenzenesulfonic acid, 3-chlorobenzenesulfonic acid, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2,4-dihydroxybenzophenone, benzenephosphinic acid, and the like.Examples of inorganic acids include hexafluorophosphoric acid, Examples include tetrafluoroboric acid and thiocyanic acid.

Further, diazo resins having a polyester-based main chain described in JP-A-54-30121;
A diazo resin obtained by reacting a polymer having a carboxylic anhydride residue described in JP-A 1-273538 with a diazo compound having a hydroxyl group; a diazo resin obtained by reacting a polyisocyanate compound with a diazo compound having a hydroxyl group : A diazo resin having a carboxyl group: a diazo resin having a phenolic hydroxyl group or the like can also be used.

The use amount of these diazo resins is preferably in the range of 0 to 40% by weight based on the solid content of the composition, and if necessary, two or more diazo resins may be used in combination.

[0055] Examples of the compound having an ethylenically unsaturated group, at least one at boiling point 100 ° C. or higher, and in one molecule at normal pressure, monomers preferably having two or more addition-polymerizable ethylenically unsaturated group Or an oligomer.
Examples of such a monomer or oligomer include, for example,
Polyethylene glycol mono (meth) acrylate [Hereinafter, methacrylate and acrylate are collectively referred to as (meth) acrylate. Monofunctional (meth) acrylates such as polypropylene glycol mono (meth) acrylate and phenoxyethyl (meth) acrylate; polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, Neopentyl glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, hexanediol di (meth) acrylate, tri (acryloyloxyethyl) isocyanurate (Meth) acrylates of polyhydric alcohol / alkylene oxide adducts and (meth) acrylates of polyhydric phenol / alkylene oxide adducts Relate, JP-B-48-41708, JP-B-50-603
4, urethane acrylates described in JP-B-51-37193 and JP-A-48-64183.
No., JP-B-49-43191, JP-B-52-3049
Polyfunctional (meth) acrylates such as polyester acrylates and epoxy acrylates obtained by adding an epoxy resin and (meth) acrylic acid described in each of JP-A No. 0 can be exemplified.

These addition-polymerizable ethylenically unsaturated compounds
The amount of the compound having a group is preferably in the range of 5 to 70% by weight based on the solid content of the composition.

Examples of the photopolymerization initiator include α-carbonyl compounds described in US Pat. No. 2,367,661, acyloin ethers described in US Pat. No. 2,448,828, and US Pat. No. 27225.
No. 12, α-hydrocarbon-substituted aromatic acyloin compounds, polycyclic quinone compounds described in U.S. Pat. No. 3,046,127, and U.S. Pat. No. 3,549,367. A combination of triarylbiimidazole / p-aminophenyl ketone,
Trihalomethyl-s-triazine compounds described in U.S. Pat. No. 4,239,850, U.S. Pat.
Oxadiazole compounds described in U.S. Pat. No. 221970, acridine and phenazine compounds described in U.S. Pat. No. 3,751,259,
Examples thereof include benzothiazole compounds described in JP-A-1-48516, and the amount thereof is preferably in the range of 0.5 to 20% by weight based on the solid content of the composition.

The photosensitive compound selected from the above (A), (B) or (C) and a polyester having a phenolic hydroxyl group, or a photosensitive resin composition containing a modified product of the polyester may contain other organic polymers. A binder may be used in combination. Examples of such an organic polymer binder include acrylic resin, polyamide resin, polyurethane resin, phenoxy resin, epoxy resin, polyacetal resin, polystyrene resin, and novolak resin.

Further, in order to improve the performance, known additives,
For example, a thermal polymerization inhibitor, a dye, a pigment, a surfactant, a plasticizer, a stability improver, and the like can be added.

Suitable dyes include, for example, crystal violet, maracay green, Victoria blue,
Basic oil-soluble dyes such as methylene blue, ethyl violet, and rhodamine B are included. As a commercial product,
For example, "Victoria Pure Blue BOH" (manufactured by Hodogaya Chemical Industry Co., Ltd.), "Oil Blue # 603" (manufactured by Orient Chemical Industry Co., Ltd.) and the like can be mentioned. Examples of the pigment include phthalocyanine blue, phthalocyanine green, dioxazine violet, quinacridone red, and the like.

Examples of the surfactant include an anionic surfactant, a nonionic surfactant, and a fluorine-based surfactant.

Examples of the plasticizer include diethyl phthalate, dibutyl phthalate, dioctyl phthalate, tributyl phosphate, trioctyl phosphate, tricresyl phosphate, tri (2-chloroethyl) phosphate, and tributyl citrate.

Further, as known stability improvers, for example,
Phosphoric acid, phosphorous acid, oxalic acid, tartaric acid, malic acid, citric acid, dipicolinic acid, polyacrylic acid, benzenesulfonic acid, toluenesulfonic acid and the like can also be used in combination.

The amounts of these various additives vary depending on the purpose, but generally, the amount of the solid content of the photosensitive composition is 0%.
The range is preferably from 30 to 30% by weight.

Further, a coating solvent can be added as required. Examples of such coating solvents include halogen solvents such as methylene chloride, chloroform, dichloroethane, trichloroethane, trichloroethylene, monochlorobenzene, dichlorobenzene, and carbon tetrachloride; hexane, heptane, cyclohexane, benzene, toluene, xylene and the like. Aliphatic or alicyclic or aromatic hydrocarbon solvents such as: tetrahydrofuran, dioxane, diethyl ether, ethyl propyl ether, dibutyl ether, ether solvents such as ethylene glycol dimethyl ether; glycol methyl ether acetate, glycol ethyl ether acetate; Ester solvents such as methyl acetate, ethyl acetate, butyl acetate, etc .; acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 4-methyl Ketone solvents such as 4-methoxy-2-pentanone; methanol, ethanol, propanol, butanol, tetrahydrofurfuryl alcohol, benzyl alcohol, diacetone alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether; Alcohol solvents such as ethylene glycol monophenyl ether and cyclohexanol; nitrogen-containing solvents such as acetonitrile, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, nitrobenzene and the like; dimethylsulfoxide and the like. Two or more kinds may be used as a mixture, and in some cases, a mixed solvent with water may be used.

The photosensitive composition thus produced is applied to a support by a known coating method such as dip coating, curtain coating, roll coating, spray coating, wheeler coating, spinner coating, air knife coating, doctor knife coating, and the like. Applied.

As the support, for example, aluminum,
Metal plate of zinc, copper, stainless steel, iron, etc .; plastic film of polyethylene terephthalate, polycarbonate, polyvinyl acetal, polyethylene, etc .; paper on which synthetic resin is melt-coated or synthetic resin solution coated, vacuum-depositing and laminating metal layer on plastic film And other materials used as a support for a printing plate. Also, in the case of a support having a metal, especially aluminum surface,
It is preferable that a surface treatment such as a graining treatment, an anodic oxidation treatment, and a hydrophilic treatment is performed. The coating amount of the photosensitive composition is usually about 0.5 to about 5 g / m ² by dry weight.

After the coating, the coating is dried by a known method to obtain a photosensitive lithographic printing plate having a photosensitive layer provided on a support.

On the photosensitive layer of the photosensitive lithographic printing plate,
In order to completely prevent the polymerization inhibiting action due to oxygen in the air, a protective layer made of a polymer having excellent oxygen barrier properties such as polyvinyl alcohol and acidic celluloses may be provided. The photosensitive layer of this photosensitive lithographic printing plate is subjected to image exposure with a negative image to cure the exposed portion of the photosensitive layer, to make it insolubilized, and then to develop with an aqueous alkaline developer substantially free of an organic solvent and to be unexposed. By dissolving and removing the portion, a lithographic printing plate having a corresponding image formed on the support can be obtained.

Suitable light sources used for exposure include, for example, carbon arc lamps, mercury lamps, metal halide lamps,
Xenon lamps, chemical lamps, lasers and the like can be mentioned.

Examples of the aqueous alkaline developer substantially free of an organic solvent according to the present invention include sodium silicate, potassium silicate, potassium hydroxide, sodium hydroxide, lithium hydroxide, sodium tertiary phosphate, and the like. Sodium diphosphate, potassium triphosphate, potassium diphosphate, ammonium triphosphate, sodium metasilicate, sodium carbonate, potassium carbonate, annimore water, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine , Diisopropanolamine, monomethylamine, dimethylamine,
An aqueous solution containing an alkaline agent such as triethylamine is exemplified.

The content of these alkali agents in the developer composition is preferably in the range of 0.05 to 10% by weight.
A range of 1 to 7% by weight is particularly preferred.

If necessary, the developer composition may contain
May include an anionic surfactant. Anion interface
As the activator, for example, lauryl alcohol sulfate
Sodium salt of octyl alcohol sulfate
Sodium salt, lauryl alcohol sulfate
Ammonium salt, secondary sodium alkyl sulfate, etc.
Higher alcohol sulfates having 8 to 22 carbon atoms
, Such as sodium cetyl alcohol phosphate
Phosphate salts of aliphatic alcohols, such as
For example, sodium salt of dodecylbenzenesulfonic acid,
Sodium naphthalene sulfonic acid sodium salt, meta
Alkyl such as sodium salt of nitrobenzenesulfonic acid
Aryl sulfonates such as C₁₇H₃₃CON
(CH_Three) CH _TwoCH_TwoSO_ThreeAlkylam such as Na
Sulfonates of sodium chloride, such as sodium sulfonamide
Acid dioctyl ester, sodium sulfosuccinate dihe
Sulfone of dibasic fatty acid ester such as xyl ester
Acid salts, for example, sodium of lauroylmethylalanine
Salt, sodium salt of lauroyl sarcosine, cocoyl
N-acylamino such as sarcosine sodium salt, etc.
Acid salts and the like.

It is suitable that the anionic surfactant is contained in an amount of 0 to 15% by weight or less based on the total weight of the developing solution at the time of use. When the content is more than 15% by weight, for example, the elution (color loss) of the dye in the photo-cured portion contained in the photo-curable photosensitive liquid becomes excessive, or mechanical and chemical properties such as abrasion resistance of the photo-cured image are obtained. The adverse effects such as deterioration of the target strength appear.

The aqueous alkaline developer of the present invention may contain a very small amount of an organic solvent.

Suitable organic solvents are those having a solubility in water of about 10% by weight or less, and preferably those having a solubility in water of 5% by weight or less. For example, 1-phenylethanol, 2-phenylethanol, 3-phenyl-1-
Propanol, 4-phenyl-1-butanol, 4-phenyl-2-butanol, 2-phenyl-1-butanol, 2-phenoxyethanol, 2-benzyloxyethanol, o-methoxybenzyl alcohol, m-methoxybenzyl alcohol, p- Methoxybenzyl alcohol, benzyl alcohol, cyclohexanol, 2-
Examples thereof include methylcyclohexanol, 4-methylcyclohexanol, and 3-methylcyclohexanol.

The amount of the organic solvent used is 2% by weight or less, preferably 1% by weight or less, based on the total weight of the developing solution at the time of use.

If necessary, an antifoaming agent and a water softener may be used.
Additives such as Water softener
As, for example, Na_TwoP_TwoO₇, Na_FiveP_ThreeO_Three, Na_Three
P_ThreeO ₉, Na_TwoO_FourP (NaO_ThreeP) PO_ThreeNa_Two, Cargo
(Polysodium metaphosphate) such as polyphosphate
For example, ethylenediaminetetraacetic acid, its potassium salt,
Sodium salt of diethylenetriaminepentaacetic acid;
Potassium salt and its sodium salt; triethylenetetra
Minhexaacetic acid, its potassium salt, its sodium salt;
Hydroxyethylethylenediaminetriacetic acid, its potassium
Salt, its sodium salt; nitrilotriacetic acid, its potassium salt
Lithium salt, its sodium salt; 1,2-diaminocyclo
Hexanetetraacetic acid, its potassium salt, its sodium
Salts; 1,3-diamino-2-propanoltetraacetic acid,
Amino acid such as its potassium salt, its sodium salt, etc.
Licarboxylic acids can be mentioned. Such hard water
Depending on the hardness of the hard water used and the amount used,
The optimum amount changes, but if you show the general amount,
Is preferably in the range of 0.01 to 5% by weight,
The range of 0.01 to 0.5% by weight is particularly preferred.

Further, the aqueous alkaline developer of the present invention includes:
If necessary, a reducing inorganic salt can be contained.
The reducing inorganic salt has a reducing action,
Water-soluble inorganic salts are preferred, and salts of lower oxygen acids are particularly preferred. For example, sodium sulfite, potassium sulfite, ammonium sulfite, lithium sulfite, sodium bisulfite, sulfites such as potassium bisulfite, sodium phosphite, potassium phosphite, sodium hydrogen phosphite, potassium hydrogen phosphite, sodium dihydrogen phosphite, And phosphites such as potassium dihydrogen phosphite. These are used alone or in combination. Of these, alkali metal salts of sulfurous acid are preferred. The content of these reducing inorganic salts in the developer composition is preferably in the range of 0.001 to 30% by weight, and particularly preferably in the range of 0.01 to 10% by weight.

The aqueous alkaline developer of the present invention may contain an aqueous pyrazolone compound, an alkali-soluble mercapto compound, a 1,3-dihydroxy aromatic compound or a salt thereof, if necessary. These are used alone or in combination. The content in the developer composition is preferably 10% by weight or less, and as the content increases, the ability to prevent contamination of the non-image area becomes higher. When the mechanical strength is deteriorated and applied to a lithographic printing plate, the printing durability is reduced.

The pH of the aqueous alkaline developer used is 11
Or more, preferably 12 or more.

Examples of such an aqueous alkaline developer containing substantially no organic solvent include, for example, JP-A-59-84.
No. 241 and JP-A-57-192952, a developer used for developing a positive type lithographic printing plate after image exposure and then developing can be used.

If necessary, after development, washing with water, desensitization, or desensitization as it is, or treatment with an aqueous solution containing an acid, or desensitization after treatment with an aqueous solution containing an acid. Processing may be performed. Furthermore, in the development process of this type of photosensitive lithographic printing plate, the alkali aqueous solution is consumed depending on the processing amount, and the alkali concentration is reduced, or the alkali concentration is reduced by air due to long-time operation of the automatic developing machine. The processing capacity is reduced.
The processing capacity may be restored using a replenisher as described in JP-A-4-62004.

[0084]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist.

(Synthesis Examples 1 to 8) Synthesis of (Modified) Polyester Having Phenolic Hydroxyl Group One-Step Method: Each mixture having the composition shown in Table 1 was mixed with a catalyst (0.4% by weight of dibutyltin oxide). The reactor was equipped with a stirrer, a nitrogen gas inlet tube, a thermometer, and a distilling tube, and heated to 190 ° C. while stirring under a nitrogen gas atmosphere to start a reaction. Thereafter, the heating and stirring were continued for 3 hours, and the distillation of the alcohol generated by the reaction was stopped, and then the pressure in the reactor was gradually reduced at the same temperature to 1 mmHg.
And Further, under the same reduced pressure, heating and stirring were further continued for about 5 hours to distill off the distillate. Then, the pressure in the reactor was returned to normal pressure with nitrogen gas, and the produced polyester resin was taken out.

Two-stage method-1: The resin (100 g) synthesized by the above-described one-stage method was heated to 180 ° C., and stirred while stirring.
The chain extender described in 1) was charged, and the pressure in the reactor was increased again to 1
The pressure was adjusted to mmHg, stirring was continued at 180 ° C. for 2 hours, and phenol produced as a by-product was distilled off. Thereafter, the pressure was returned to normal pressure, and the resulting modified polyester resin was taken out.

Two-step method-2: The resin (100 g) synthesized by the above-described one-step method was heated to 140 ° C., and the chain extender shown in Table 1 was charged with stirring, and kept at normal pressure for 4 hours at 140 ° C. The reaction was continued while stirring, and the resulting modified polyester resin was taken out. By the above synthesis method, (modified) polyesters 1 to 8 having phenolic hydroxyl groups having the weight average molecular weights shown in Table 1 were obtained.

[0088]

[Table 1]

(Examples 1 to 5) An aluminum plate having a thickness of 0.30 mm was degreased with an aqueous sodium hydroxide solution, and this was subjected to electrolytic polishing in a 2% hydrochloric acid bath to obtain a center line average roughness (R).
a) A grained board of 0.6 μm was obtained. Then, in a 20% sulfuric acid bath, anodizing was performed at a current density of 2 A / dm ² to obtain 2.7 g.
/ M ² , and then sealed in a 3% aqueous solution of No. 3 sodium silicate at 60 ° C. for 1 minute, washed with water and dried to obtain a support.

The support was coated with the following photosensitive solution using a roll coater and dried at 100 ° C. for 3 minutes to obtain a photosensitive lithographic printing plate. At this time, the weight of the dried coating film was 2.0 g / m ² .

[Photosensitive Liquid (Photosensitive Composition)] (Modified) Polyester 10.0 g Diazo resin ^{* 1)} 1.2 g Malic acid 0.1 g "Victoria Pure Blue BOH" ^{* 2)} 0.25 g Ethylene glycol monomethyl ether 200 g

* 1) The diazo resin is a p-toluenesulfonic acid salt of a condensate of 4-diazodiphenylamine and paraformaldehyde. * 2) Victoria Pure Blue BOH is a basic oil-soluble dye manufactured by Hodogaya Chemical Industry Co., Ltd.

A film of a halftone dot negative image and a step of 0.15 step wedge were brought into close contact with the obtained photosensitive lithographic printing plate, and a light sensitivity of 4 was obtained by using a metal halide lamp of 2 kW output provided at a position 1 m away from the film. Exposure was performed for an exposure time that was a solid step. Thereafter, development was performed with the following developer at 25 ° C. for 1 minute, and after washing with water, a gum solution was applied to obtain a lithographic printing plate.

[Developer] 1K aqueous potassium silicate solution (50%) 4.0 g sodium hydroxide 1.0 g sodium sulfite 0.5 g sodium alkylnaphthalenesulfonate 1.5 g water 93.0 g

The prepared lithographic printing plate was mounted on a Roland Fabolit printing machine, and the printing ink “CAPS-G Beni” was used.
(Manufactured by Dainippon Ink and Chemicals, Inc.), fountain solution "DH-7"
8 "(manufactured by Dainippon Ink and Chemicals, Inc.) using a 400-fold dilution.

The printing durability was evaluated on the basis of whether or not a printed matter faithful to the original image was obtained at the time of printing 50,000 sheets without causing dot thickening, plate skipping and the like.

The evaluation results are summarized in Table 2. On the other hand, the photosensitive lithographic printing plate was treated with this developer to 4 m ² per liter of the developer, but no scum or sludge was observed.

For comparison, FNS-A (manufactured by Fuji Photo Film Co., Ltd.), which is a commercially available diazo-based negative PS plate, was exposed and developed under the same conditions as in Example 1, but could not be developed.

[0099]

[Table 2]

(Examples 6 to 13) The following photosensitive solution was applied to a support treated in the same manner as in Examples 1 to 5 using a roll coater and dried at 100 ° C. for 3 minutes to obtain a photosensitive lithographic printing plate. Was. At this time, the weight of the dried coating film was 2.0 g / m ² .

[Photosensitive Liquid (Photosensitive Composition)] (Modified) Polyester 10.0 g Urethane acrylate ^{* 3)} 5.0 g Diazo resin (same as in Example 1) 0.7 g 2- (4-methoxynaphthyl) -4,6-bis (trichloromethyl) -S-triazine 0.5 g oxalic acid 0.15 g "Victoria Pure Blue BOH" 0.2 g ethylene glycol monomethyl ether 150 g methyl ethyl ketone 50 g

* 3) Urethane acrylate is an adduct of “Millionate MR” (manufactured by Nippon Polyurethane Industry Co., Ltd., MDI polyisocyanate) and pentaerythritol triacrylate.

A film of a halftone dot negative image and a step of 0.15 step wedge were brought into close contact with the obtained photosensitive lithographic printing plate, and a light sensitivity of 4 was obtained by using a metal halide lamp of 2 kW output provided at a position 1 m away from the film. Exposure was performed for an exposure time that was a solid step. Thereafter, development was performed at 25 ° C. for 1 minute with the developing solution, and after washing with water, a gum solution was applied to obtain a lithographic printing plate.

The prepared lithographic printing plate was mounted on a Roland Fabolit printing machine, and the printing ink “CAPS-G Beni” was used.
(Manufactured by Dainippon Ink and Chemicals, Inc.), fountain solution "DH-7"
8 "(manufactured by Dainippon Ink and Chemicals, Inc.) using a 400-fold dilution.

The printing durability was evaluated on the basis of whether or not a printed matter faithful to the original image was obtained at the time when 100,000 sheets were printed, without causing dot thickening, plate skipping and the like.

The evaluation results are summarized in Table 3.

On the other hand, the photosensitive lithographic printing plate was treated with this developer up to 4 m ² per liter of developer, but no scum or sludge was found.

For comparison, a styrene / maleic anhydride copolymer [SMA-3] was used instead of the (modified) polyester.
000, manufactured by Arco Chemical Co., Ltd.] and a resin having a phenolic hydroxyl group introduced into its side chain by an addition reaction with p-aminophenol ", to prepare a photosensitive lithographic printing plate under the same conditions as in Example 6. When exposed and developed, the developability was good, but the printing durability was poor and plate skipping occurred on 20,000 sheets.

[0109]

[Table 3]

(Examples 14 to 16) In preparing the supports of Examples 1 to 5, instead of performing anodizing treatment in a 20% sulfuric acid electrolyte, an oxide film was formed in a 20% phosphoric acid electrolyte. A support was obtained in the same manner except that the anodic oxidation treatment was performed to 1.5 g / m ² .

The support was coated with the following photosensitive solution using a roll coater and dried at 100 ° C. for 3 minutes to obtain a photosensitive lithographic printing plate. At this time, the weight of the dried coating film was 1.8 g / m ² .

[Photosensitive Liquid (Photosensitive Composition)] (Modified) Polyester 10.0 g Urethane acrylate (same as that used in Examples 6 to 13) 5.0 g 2- (4-methoxynaphthyl) -4,6 -Bis (trichloromethyl) -S-triazine 0.6 g copper phthalocyanine pigment 0.2 g methyl ethyl ketone 50 g ethylene glycol monomethyl ether 150 g

(Modified) Each photosensitive lithographic printing plate obtained using polyester Nos. 1, 6, and 7 was subjected to the same treatment and test as in Examples 1 to 5, and the results are shown in Table 4. .

[0114]

[Table 4]

[0115]

According to the photosensitive resin composition of the present invention, a negative photosensitive lithographic printing plate is developed with an aqueous alkaline developer substantially free of an organic solvent, whereby scum or the like is contained in the developer. A planographic printing plate can be obtained without sludge or the like. Further, since the developing solution does not contain an organic solvent, there are no problems in hygiene such as toxicity and odor at the time of work, and safety problems such as fire and gas explosion. Further, a negative type lithographic printing plate can be manufactured by the same process as that of a conventional positive type photosensitive lithographic printing plate. Therefore, with one kind of developer and one automatic developing machine,
Both negative and positive planographic printing plates can be processed.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-4-172456 (JP, A) JP-A-62-174744 (JP, A) JP-A-60-221748 (JP, A) 29147 (JP, A) JP-A-5-5986 (JP, A) JP-A-4-134346 (JP, A) JP-A-60-203630 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03F 7/021 501 G03F 7/00 503 G03F 7/027 502 G03F 7/032 502

Claims (4)

(57) [Claims] 1. A polyester having a phenolic hydroxyl group, a modified product of the polyester, and an addition-polymerizable ethylene
A photosensitive resin composition comprising a compound having an unsaturated group and a photopolymerization initiator . 2. A method represented by the following general formulas (1) to (5):
Dicarboxylic acids having an enolic hydroxyl group or derivatives thereof
A polycarboxylic acid component and a polyhydric alcohol component
Having phenolic hydroxyl groups derived from
Ter or modified polyester, and photosensitive diazo
Containing 1000 g of the polyester or modified polyester
The structural units represented by the general formulas (1) to (5)
A photosensitive resin composition characterized by containing at least one mole . Embedded image Embedded image Embedded image Embedded image Embedded image 3. The method according to claim 1, wherein the support is provided on a support.
Photosensitive layer having a photosensitive layer comprising a photosensitive resin composition according to the present invention.
Plate printing plate . 4. The method according to claim 3, wherein the photosensitive lithographic printing plate is used as an image.
After exposure, aqueous alkali development containing substantially no organic solvent
A method for producing a lithographic printing plate, comprising developing with a liquid .