JP2650323B2 - Photosensitive composition - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a diazo photosensitive composition, and more particularly, to a negative composition suitable for coating on a support used in the production of offset plates, letterpress plates, gravure plates and the like. Type diazo photosensitive composition.

(Prior art) By exposing a photosensitive plate obtained by coating a thin film of a photosensitive substance on a support and exposing through a transparent image, a difference in solubility is caused between an exposed portion and an unexposed portion, and an appropriate solvent is used. Various techniques for developing and forming a relief image on a photosensitive plate have been proposed.

As the photosensitive composition used for such a purpose,
It is well known that a combination of a diazo compound and a polymer compound is a negative type lithographic printing plate.

As the polymer compound used in combination with the diazo compound, a hydroxyl group, an amino group, a cyano group,
High molecular compounds having a functional group such as a urethane group are effective, for example, described in JP-B-57-43890.
Polymer compounds having a phenolic hydroxyl group or p-hydroxyphenyl (meth) acrylamide in the polymer structure, 2-oxyalkyl (meth) compounds described in JP-B-52-7364 and JP-B-55-34929. A polymer compound having an alcoholic hydroxyl group, such as a polymer compound containing an acrylate monomer, a diazo compound, a polymer compound containing a 2-oxyalkyl (meth) acrylate monomer and an acrylonitrile monomer, and the like are known.

(Problems to be Solved by the Invention) A photosensitive composition containing these high molecular compounds used in combination with a diazo compound is applied to a metal plate such as aluminum and used as a lithographic printing plate material. In general, there is a demand for higher printing durability and improved resist properties against various processing chemicals used at the time of printing. At the same time, good developability and affinity with printing inks are also required.

Accordingly, an object of the present invention is to provide a diazo photosensitive composition which satisfies the above requirements when coated on a support and used as a photosensitive lithographic printing material, and which provides a printing plate with high sensitivity and good UV ink suitability. To provide things.

(Means for Solving the Problems) The present inventors have conducted intensive studies to achieve the above objects, and as a result, using a specific polymer having a copolymer of acrylonitrile as a branch polymer component as a polymer compound. As a result, it was found that the object was achieved, and the present invention was completed.

That is, the gist of the present invention is that in a photosensitive composition containing a photosensitive diazo compound and a polymer compound, the polymer compound has a structural unit derived from a monomer represented by the following general formula (1) as a component. A photosensitive composition, which is a copolymer.

Hereinafter, the present invention will be described in detail.

The monomer represented by the above general formula (1) is a kind of a compound generally called a macromer, and the synthesis method of the macromer is not particularly limited.

The most common method of macromer synthesis is a method in which a prepolymer such as a terminal carboxylic acid or alcohol is synthesized by a radical polymerization using a chain transfer agent, and a double bond is introduced by terminal group conversion. In particular, macromers are easily synthesized by a combination of an acrylic monomer and a mercaptan-based chain transfer agent.

The method of introducing a polymer group into a terminal by the above synthesis method is called a termination method or an end cap method. Conversely, there is also a method of introducing a terminal polymer group by using a compound having a carboxyl group as an initiator, and such a method is called a normal initiation method.

In addition to the above synthesis method, there is a method of synthesizing a macromer by living polymerization or the like. Methods for synthesizing these macromers are described, for example, in US Pat.
No .; PFRempp, E. Franta, Advances in Polymer Science,
58,1 (1984); J. Polymer Letters Edition, 19,629 (198
1); Polymer J., 14, 255 (1982); Polymer processing 34,439 (1
985); Polymer 31,988 (1982) and the like.

In the general formula (1), X represents an atom or a molecule that is inevitably introduced between the terminal polymer group and the prepolymer when the terminal polymer group is introduced as described in the above synthesis method. And often contains sulfur atoms.

The Y component in the formula represents a copolymer component containing at least one structural unit derived from acrylonitrile. The monomer forming the copolymer preferably contains acrylonitrile in an amount of 10 mol% or more, but the other structural units of the copolymer are monomers capable of radical polymerization with acrylonitrile and have an unsaturated bond shown below. Compounds are used.

(1) Monomers having a hydroxyl group: 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxypentyl (meth) acrylate, 4-hydroxyphenyl (meth) acrylate, 2-hydroxyphenyl ( (Meth) acrylate monomers such as (meth) acrylate, N-methylol (meth) acrylamide, N-hydroxyethyl (meth) acrylamide, N- (hydroxyphenyl)-
(Meth) acrylamide, N- (hydroxynaphthyl)
-(Meth) acrylamide monomers such as (meth) acrylamide, o-, m- or p-hydroxystyrene monomers, etc. (2) (meth) acrylic acid ester or amide monomers other than (1): methyl (meth) Alkyl (meth) acrylates such as acrylate, ethyl (meth) acrylate and propyl (meth) acrylate, (meth) acrylamide and the like (3) Monomers having a cyano group in the side chain: 2-pentenyltolyl, 2-methyl-3 -Butenenitrile, 2-cyanoethylacrylate, o-, m- or p-cyanostyrene, etc. (4) Monomers having a carboxylic acid in the side chain: (meth) acrylic acid, itaconic acid and its anhydride, maleic acid and its Anhydrides, crotonic acid, etc. (5) Vinyl ethers: propyl vinyl ether,
Butyl vinyl ether, octyl vinyl ether, phenyl vinyl ether, etc. (6) Styrenes: α-methylstyrene, methylstyrene, chloromethylstyrene, styrene, etc. (7) Vinyl ketones: methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, etc. (8) Monomers other than (1) to (7): ethylene,
Examples include olefins such as propylene, isobutylene, butadiene, and vinyl chloride, N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, and the like, and any other monomer that can cause radical polymerization with these monomers.

The monomer as a constituent component unit of the Y component in the present invention is not limited to those described above. In the polymer compound of the photosensitive composition of the present invention, structural units other than the structural unit derived from the monomer represented by the general formula (1) include:
Usually, it constitutes the main chain of the graft polymer which is the polymer compound. As the structural unit, any monomer that can be radically copolymerized with the monomer of the above general formula (1) can be used.

Examples of these monomers include (meth) acrylonitrile and monomers of the same type as the monomers capable of forming the Y component.

The weight ratio of the main chain polymer component to the branch polymer component in the polymer compound is preferably 0.5 to 80% by weight, particularly preferably 3 to 50% by weight, based on the total weight.

As a method for synthesizing the polymer compound in the composition of the present invention, a system in which the monomer of the general formula (1) is added in the same manner as the other monomers, for example, by a known radical polymerization method or the like, It is easily synthesized by a solution polymerization method using an initiator (0.1 to 4.0 mol%) such as bisisobutyronitrile and benzoyl peroxide.

In addition, the method of synthesizing the graft polymer in this manner is referred to herein as a macromer method.

As the molecular weight of the polymer compound, generally known gel permeation chromatography (hereinafter referred to as GPC
Method, the weight-average molecular weight is preferably 10,000 to 1,000,000, and particularly preferably 50,000 to 600,000.

The content of the polymer compound in the photosensitive composition is preferably from 30 to 99% by weight, particularly preferably from the total composition.
40-97% by weight.

As the diazo compound used in the present invention, conventionally known diazo compounds can be appropriately used. Examples thereof include a diazo resin typified by a condensate of an aromatic diazonium salt and, for example, an active carbonyl-containing compound, particularly, formaldehyde. Solvent-soluble diazo resins are preferred.

Preferred specific examples of the diazo resin include a resin represented by the following general formula (2), wherein l and m in the formula are 2 or more.

In the formula, R ² , R ³ and R ⁴ represent a hydrogen atom, an alkyl group or an alkoxy group, and R ⁵ represents a hydrogen atom, an alkyl group or a phenyl group.

V in the formula represents a counter anion of the diazo resin, and specifically, PF ₆ , BF ₄ , organic carboxylic acids, organic phosphoric acids and
It shows sulfonic acids and the like.

W in the formula represents NH, S or O. Further, U in the formula represents a phenyl group or a naphthyl group substituted with at least one or more substituents selected from a sulfonic acid group, a sulfonic acid group, a sulfinic acid group, a sulfinic acid group, a hydroxyl group, and a carboxyl group. .

Preferable examples of other diazo resins include a resin represented by the following general formula (3), wherein s in the formula is 2 or more.

In the formula, R ^{2 to} R ⁵ , V and W have the same meanings as in the general formula (2).

The content of the diazo resin in the photosensitive composition according to the present invention is preferably 1 to 70% by weight, more preferably 3 to 60% by weight.

The photosensitive composition of the present invention may further contain, if necessary, a dye, a pigment, a coating improver, a plasticizer, or another polymer compound, in addition to the above-described materials.

Examples of the dye include Victoria Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd.), Oil Blue # 603 (manufactured by Orient Chemical Co., Ltd.), Patent Pure Blue (manufactured by Sumitomo Mikuni Chemical Co., Ltd.), crystal violet, brilliant green, ethyl violet, Methyl green, erythrosin B, basic fuchsin, malachite green, oil red, m-cresol purple, rhodamine B,
Triphenylmethane-based, diphenylmethane-based, oxazine-based, xanthene-based, iminonaphthoquinone-based, azomethine-based or anthraquinone-based dyes represented by auramine, 4-p-diethylaminophenyliminonaphthoquinone, cyano-p-diethylaminophenylacetanilide, etc. No.

The dye is usually present in the photosensitive composition in an amount of about 0.5 to about 10% by weight,
Preferably, the content is about 1 to 5% by weight.

Examples of the coatability improver include alkyl ethers (for example, ethyl cellulose and methyl cellulose), fluorine-based surfactants, and nonionic surfactants (for example, Pluronic L-64 (manufactured by Asahi Denka Co., Ltd.)). As plasticizers for imparting flexibility and abrasion resistance, for example, butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate , Trioctyl phosphate, tetrahydrofurfuryl oleate, oligomers of acrylic acid or methacrylic acid, and examples of the sensitizer for improving the lipophilic property of the image area include those described in JP-A-55-527. Half ester of styrene-maleic anhydride copolymer with alcohol And stabilizers such as polyacrylic acid, tartaric acid, phosphoric acid, phosphorous acid, and organic acids (acrylic acid, methacrylic acid, citric acid,
Oxalic acid, benzenesulfonic acid, naphthalenesulfonic acid, 4-methoxy-2-hydroxybenzophenone-5
-Sulfonic acid). The amount of these additives varies depending on the purpose of use, but is generally preferably 0.01 to 30% by weight based on the total solid content.

The photosensitive composition of the present invention is dissolved in a solvent in which each of the above components is dissolved, and the resulting solution is applied to the surface of a support and dried to form, for example, a photosensitive lithographic printing plate material or a photoresist (eg, a resin relief printing material, a printed wiring board). Base plate etc.) can be formed.

Hereinafter, the case where a lithographic printing plate material is obtained by using the photosensitive composition of the present invention will be described.

Solvents that can be used include methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve, cellosolves such as ethyl cellosolve acetate, methyl carbitol, carbitols such as ethyl carbitol, dimethylformamide, dimethyl sulfoxide, dioxane, acetone, cyclohexanone, Trichloroethylene, methyl ethyl ketone and the like. These solvents are used alone or in combination of two or more.

The coating method can be a conventionally known method, for example, spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating, curtain coating, or the like. The coating amount varies depending on the application, but the photosensitive lithographic printing plate material preferably has a solid content of 0.15 to 10 g / m ² .

In the photosensitive lithographic printing plate material using the photosensitive composition of the present invention, the support is a metal plate of aluminum, zinc, copper, steel or the like; chromium, zinc, copper, nickel, aluminum, iron, or the like is plated or deposited. Metal plate, paper, plastic film and glass plate; paper coated with resin; paper covered with metal foil such as aluminum; plastic film subjected to hydrophilic treatment. Of these, an aluminum plate is preferred. When an aluminum plate is used as a support for a photosensitive lithographic printing plate material,
It is preferable that surface treatment such as anodizing treatment and, if necessary, sealing treatment be performed. A known method can be applied to these processes.

Examples of the graining method include a mechanical method and an electrolytic etching method. Examples of the mechanical method include a ball polishing method, a brush polishing method, a polishing method using liquid honing, and a buff polishing method. The above-described various methods can be used alone or in combination depending on the composition of the aluminum material and the like.

The electrolytic etching is performed in a bath containing an inorganic acid such as hydrochloric acid or nitric acid.

After the graining treatment, if necessary, a desmut treatment is performed with an aqueous solution of an alkali or an acid to neutralize and wash with water.

The anodizing treatment uses sulfuric acid, chromic acid,
The electrolysis is performed by using a solution containing one or more of oxalic acid, phosphoric acid, malonic acid and the like and using an aluminum plate as an anode. Anodized film amount formed is suitably 1 to 50 mg / dm ^2, preferably 10 to 40 mg / dm ^2, particularly preferably 25~40mg / dm ^2. The amount of anodized film can be measured, for example, by coating an aluminum plate with a chromic phosphate solution (phosphoric acid 85% solution:
l, Chromium (VI) oxide: 20g dissolved in 1 water
To dissolve the oxide film and measure the weight change before and after dissolution of the film on the plate.

Specific examples of the sealing treatment include boiling water treatment, steam treatment, sodium silicate treatment, and dichromate aqueous solution treatment. In addition, the aluminum plate support may be subjected to an undercoating treatment with an aqueous solution of a water-soluble polymer compound or a metal salt such as fluorinated zirconic acid.

In addition, in general, when a film original is closely adhered to a photosensitive lithographic printing plate material, baking is performed under vacuum, and a method for improving the vacuum adhesion is also known as photosensitive lithographic printing using the photosensitive composition of the present invention. Can be applied to plate material. Methods for improving vacuum adhesion include a method of mechanically embossing the surface of the photosensitive layer, a method of spraying solid powder on the surface of the photosensitive layer, and a photosensitive layer as described in JP-A-50-125805. Method of providing a mat layer on the surface, and JP-A-55-1297
A method of thermally fusing a solid powder to the surface of a photosensitive layer as described in JP-A No. 4 (1993) -104, etc. may be mentioned.

For the photosensitive lithographic printing plate material coated on the support, a conventional method is applied. That is, by exposing through a transparent original image having a line image, a halftone dot image, and the like, and then developing with an aqueous developer, a negative relief image with respect to the original image is obtained. Light sources suitable for exposure include carbon arc lamps, mercury lamps, xenon lamps, metal halide lamps,
Strobes and the like can be mentioned.

The developer used in the development of the photosensitive lithographic printing plate material of the present invention may be any known developer, but preferably contains a specific organic solvent, an alkali agent, and water as essential components. I do. Here, the specific organic solvent is capable of dissolving or swelling the above-mentioned non-exposed portion (non-image portion) of the photosensitive composition layer when it is contained in a developing solution, and furthermore, water at normal temperature (20 ° C.) Refers to an organic solvent having a solubility in water of 10% by weight or less. Such organic solvents may be those having the above-mentioned properties, and are not limited to the following. Examples thereof include ethyl acetate, propyl acetate and acetic acid. Carboxylic esters such as butyl, amyl acetate, benzyl acetate, ethylene glycol monobutyl acetate, butyl lactate and butyl levulinate: ketones such as ethyl butyl ketone, methyl isobutyl ketone and cyclohexanone: ethylene glycol monobutyl ether, ethylene glycol benzyl ether; Alcohols such as ethylene glycol monophenyl ether, benzyl alcohol, methylphenyl carbinol, n-amyl alcohol, methyl amyl alcohol: alkyl-substituted aromatic hydrocarbons such as xylene: methylene dichloride, d Range chloride, and the like halogenated hydrocarbons monochlorobenzene and the like. One or more of these organic solvents may be used. Among these organic solvents, ethylene glycol molophenyl ether and benzyl alcohol are particularly effective. Also,
The content of these organic solvents in the developer is generally from 1 to 20% by weight, and particularly preferably from 2 to 10% by weight.

On the other hand, examples of the alkaline agent contained in the developer include (A) sodium silicate, potassium silicate, potassium hydroxide, sodium hydroxide, lithium hydroxide, sodium or ammonium salt of secondary or tertiary phosphoric acid, Inorganic alkaline agents such as sodium metasilicate, sodium carbonate, and ammonia (B) mono, di or trimethylamine, mono, di or triethylamine, mono or diisopropylamine, n-
Organic compounds such as butylamine, mono-, di- or triethanolamine, mono-, di- or triisopropanolamine, ethyleneimine, ethylenediamine and the like can be mentioned.

Preferred are (A) potassium silicate and sodium silicate, and (B) an organic amine compound, and particularly preferred are (A) potassium silicate and (B) di- or triethanolamine.

The content of these alkali agents in the developer is usually 0.1.
It is from 05 to 8% by weight, preferably from 0.5 to 6% by weight.

Further, in order to further improve the storage stability, printing durability, and the like, it is preferable to include a water-soluble sulfite in the developer as required. As such a water-soluble sulfite, an alkali or alkaline earth metal sulfite is preferable, and examples thereof include sodium sulfite, potassium sulfite, lithium sulfite, and magnesium sulfite. The content of these sulfites in the developer composition is usually 0.05 to 4% by weight, preferably 0.1 to 1% by weight.

In addition, a certain solubilizing agent may be included to assist the dissolution of the above-mentioned organic solvent in water. As such a solubilizer, in order to achieve the desired effect of the present invention,
Low-molecular-weight alcohol, which is more soluble in water than the organic solvent used,
It is preferable to use ketones. Further, an anionic activator, an amphoteric activator and the like can also be used. Such alcohols and ketones include, for example, methanol, ethanol,
It is preferable to use propanol, butanol, acetone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methoxybutanol, ethoxybutanol, 4-methoxy-methylbutanol, N-methylpyrrolidone and the like. As the activator, for example, sodium isopropylnaphthalenesulfonate, sodium n-butylnaphthalenesulfonate, sodium N-methyl-N-pentadecylaminoacetate, sodium salt of lauryl sulfate and the like are preferable. The amount of these solubilizers such as alcohols and ketones to be used is not particularly limited, but is generally preferably about 30% by weight or less based on the whole developer.

The above photosensitive lithographic printing plate material, after imagewise exposure, if it is brought into contact with the above-mentioned developer or rubbed, after about 10 to 60 seconds at about 10 ° C to 40 ° C, exposure of the photosensitive layer The photosensitive composition in the non-exposed area is completely removed without adversely affecting the area.

(Examples) Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

Synthesis of Macromer 1 Under a nitrogen stream, styrene (40 mol%), acrylonitrile (40 mol%), thioglycolic acid (16.6 mol%), azobisisobutyronitrile (0.4 Mol%), and the mixture was reacted at 60 ° C. for 3 hours with stirring to obtain a terminal acid prepolymer. After completion of the reaction, the reaction solution was poured into water to precipitate a terminal acid prepolymer, and dried at 50 ° C. in a vacuum for 24 hours. Further, this terminal acid prepolymer was dissolved in a xylene solvent, and glycidyl methacrylate (equimolar to the thioglycolic acid), a small amount of hydroquinone and N, N
-Dimethyllaurylamine was added and reacted at 140 ° C for 1 hour. After completion of the reaction, the reaction solution is poured into water, and the precipitate is removed.
It was vacuum-dried at 50 ° C. all day and night to obtain Macromer 1.

Synthesis of Macromer 2 Macromer 2 was obtained in the same manner as in Macromer 1 except that methyl methacrylate was used instead of styrene.

Synthesis of Macromer 3 Under a nitrogen stream, styrene (40 mol%), acrylonitrile (40 mol%), 4,4'-azobis (4-cyano) valeric acid (20 mol%) ) Was dissolved, and the mixture was reacted at 60 ° C. for 3 hours with stirring to obtain a terminal acid prepolymer. After completion of the reaction, the reaction solution was poured into water to precipitate a terminal acid prepolymer, and dried at 50 ° C. in a vacuum for 24 hours. Further, this terminal acid prepolymer is dissolved in a xylene solvent, and glycidyl methacrylate (equimolar to the above 4,4'-azobis (4-cyano) valeric acid), small amounts of hydroquinone and triethylamine are added thereto, and the mixture is added at 140 ° C. for 1 hour. Reacted. After the completion of the reaction, the reaction solution was poured into water, and the precipitate was vacuum-dried at 50 ° C. overnight to obtain Macromer 3.

Synthesis of Graft Polymer A graft polymer having the charging ratio of each monomer shown in Table 1 below was synthesized according to the following procedure.
(In the table, each number represents weight percent unless otherwise specified. In the table, HyPMA represents p-hydroxyphenyl methacrylamide, AN represents acrylonitrile, MA represents methyl acrylate, EA represents ethyl acrylate, and MAA represents methacrylic acid. The macromer shows the number of the macromer used on the left side and the weight percentage on the right side, and the column indicated by Mw shows the weight average molecular weight of the synthesized polymer compound by GPC. The results obtained by the method are shown in thousands. The same applies to Table 2.) Under a nitrogen stream, a monomer having a charge ratio shown in Table 1 below was added to a mixed solvent of 18 g of acetone and 18 g of methanol in a total weight of 20.
g and 0.5 g of azobisisobutyronitrile (AIBN) were dissolved, and the mixture was heated at 60 ° C. for 6 hours with stirring. After the completion of the reaction, the reaction solution was poured into water to precipitate a copolymer, followed by vacuum drying at 50 ° C for 24 hours to obtain graft polymers GP-1 to GP-7.

Synthesis of Comparative Polymer In addition, in order to confirm the effectiveness of the present invention, using the monomers shown in Table 2 as Comparative Examples, using the same method as the procedure shown in the synthesis of the graft polymer except that no macromer was used. Comparative polymers RA-1 and RA-2 were obtained.

Synthesis of diazo resin 1 14.5 g (50 mmol) of p-diazodiphenylamine sulfate was dissolved in 40.9 g of concentrated sulfuric acid under ice cooling. 1.5 g (50 mmol) of paraformaldehyde was slowly added dropwise to the reaction solution. At this time, the addition was performed so that the reaction temperature did not exceed 10 ° C. Thereafter, stirring was continued for 2 hours under ice cooling. The reaction mixture was added dropwise to 500 ml of ethanol under ice cooling, and the resulting precipitate was removed. After washing with ethanol,
This precipitate was dissolved in 100 ml of pure water, and a cold concentrated aqueous solution in which 6.8 g of zinc chloride was dissolved was added to the solution. After passing through the resulting precipitate, the precipitate was washed with ethanol and dissolved in 150 ml of pure water. To this solution, a cold concentrated aqueous solution in which 8 g of ammonium hexafluorophosphate was dissolved was added. The resulting precipitate was removed, washed with water, and dried at 30 ° C. for 24 hours to obtain diazo resin 1.

When the molecular weight of this diazo resin 1 was measured, it was found that about 50 mol% of pentamer or more was contained.

Synthesis of diazo resin 2 Instead of 14.5 g of p-diazodiphenylamine sulfate, 3-methoxy-4-diazodiphenylamine sulfate was used.
Diazo resin 1 except 16.1 g (50 mmol)
In the same manner as in the above, diazo resin 2 was obtained.

Manufacture of grain 1 A 0.24 mm thick aluminum plate is immersed in a 3% aqueous sodium hydroxide solution, degreased and washed, and then placed in a 1% aqueous hydrochloric acid solution at 25 ° C.
Electroetched at a current density of 100 A / dm ² for 1 minute, washed with water, immersed in 0.9% sodium hydroxide aqueous solution, washed with water, and in a 30% sulfuric acid aqueous solution at 30 ° C. and a current density of 1.5 A / dm ² for 30 seconds. Anodized, washed with water, and immersed in a 1% sodium metasilicate solution at 85 ° C. for 3 minutes to perform a sodium silicate treatment. Thereafter, it was immersed in water (pH 8.5) at 90 ° C. for 25 seconds, washed with water and dried to form a grain 1.

Manufacture of grain 2 An aluminum plate with a thickness of 0.24 mm is
Using a 0 mesh pumiceton-water suspension, the surface is sanded, washed well with water, immersed in 1% sodium hydroxide for 13 seconds, and 4.0 A in a 40% phosphoric acid aqueous solution at 30 ° C. / dm ²
At a current density of 30 seconds, and immersed in a 1% sodium metasilicate solution at 85 ° C. for 3 minutes to perform sodium silicate treatment. Thereafter, it was immersed in water at 90 ° C. for 2 minutes, washed with water and dried to form a grain 2.

Examples 1 to 10 and Comparative Examples 1 to 4 An aluminum plate obtained by producing grain 1 or 2 as described above was composed of the composition shown in Table 3, 0.3 g of polyacrylic acid and 0.2 g of Victoria Pure Blue BOH. Photosensitive liquid 1-1
1 was applied using a wheeler and dried at 85 ° C. for 3 minutes to obtain a photosensitive lithographic printing plate. The combinations of the grain and the photosensitive solution are as shown in Table 4.

The obtained photosensitive lithographic printing plate is 100
After exposure for 30 seconds from a distance of cm, the following developer was diluted with water and developed at 25 ° C. for 45 seconds. The developability under each dilution condition was evaluated according to the following criteria.

(Composition of developer) Benzyl alcohol 50g Triethanolamine 15g Sodium sulfite 5g Sodium butylnaphthalenesulfonate 25g Water 500g (Evaluation criteria) 10: Good development 5: Poor development (stained) 1: Not developable Further dilution ratio x The lithographic printing plate developed with the developing solution of No. 2 was printed on a high quality paper with a general ink (Toyo Ultra King Red) using a GTO printing machine manufactured by Heidelberg Co., Ltd., and the printing durability was examined.

In order to examine the suitability of UV ink, an immersion test and
Printing with UV ink was performed.

The immersion test was performed on a lithographic printing plate obtained by developing with a roll cleaner for best cure (manufactured by Toka Dye Chemical Co., Ltd.), which is a cleaner used for printing with UV ink, using a developer with an exposure and dilution ratio of 2 For 24 hours. Then, the ratio of the reflection density of the image portion after the test to the reflection density of the image portion before the test was measured.

Next, using a GTO printing machine equipped with a UV irradiation device, printing was performed on high quality paper as a UV ink using Best Cure manufactured by Toka Dye Chemical Co., Ltd., and the printing durability was examined.

 Table 4 shows the results.

From the above Examples 1 to 10 and Comparative Examples 1 to 4, when the photosensitive composition of the present invention is used, the printing durability is extremely excellent, and the printing durability in printing with UV ink is also excellent. It can be seen that a photosensitive lithographic printing plate having good developability can be obtained.

(Effects of the Invention) As described in detail above, when the polymer compound of the present invention is used in a photosensitive composition, a photosensitive composition having high printing durability, excellent developability, and UV ink suitability can be obtained. A remarkable effect that a layer is obtained can be obtained.

Therefore, the present invention is very useful industrially.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masafumi Uehara 1 Sakuracho, Hino-shi, Tokyo Konica Corporation (72) Inventor Shinichi Matsubara 1 Sakuracho, Hino-shi, Tokyo Konica Corporation (56) References JP-A-50-83101 (JP, A) JP-B-45-9614 (JP, B1)

Claims (1)

(57) [Claims] 1. A photosensitive composition containing a photosensitive diazo compound and a polymer compound, wherein the polymer compound comprises a structural unit derived from a monomer represented by the following general formula (1) as a constituent. A photosensitive composition characterized by being united.