JPH08211603A - Photosensitive composition, photosensitive lithographic printing plate and method for developing the same - Google Patents

Abstract

(57) [Summary] [Purpose] There is no sensitivity fluctuation due to the difference in oxygen concentration, it is not necessary to provide an oxygen barrier layer, and it is possible to develop with an alkaline aqueous solution containing substantially no organic solvent. To provide a photosensitive composition having sufficient printing durability and a photosensitive lithographic printing plate. [Structure] A compound represented by the general formula (I) or (II),
A photosensitive composition containing a compound represented by formula (III), a polymerizable compound having an addition polymerizable unsaturated bond, and a polymer compound capable of forming a film.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a photosensitive composition, a photosensitive lithographic printing plate and a method for developing the same, and more specifically,
The present invention relates to a photosensitive composition and a photosensitive lithographic printing plate which are free from sensitivity fluctuation due to oxygen concentration difference and have excellent developability and printing durability.

[0002]

BACKGROUND OF THE INVENTION A photopolymerizable composition using a polymerizable compound having an addition-polymerizable unsaturated bond is photopolymerized by irradiation with actinic rays such as ultraviolet rays to become a polymer. It is used as a light-sensitive material for forming an image by utilizing changes in physical properties such as solubility and adhesiveness associated with the change to the polymer.

When an image is formed using a light-sensitive material having such a photopolymerizable composition as a light-sensitive layer, the radical polymerization reaction is hindered in the presence of oxygen, resulting in a decrease in sensitivity and a change in sensitivity due to a change in oxygen concentration. there were. To solve this, a transparent film called a cover sheet is attached to the surface of the photosensitive layer, or a transparent polymer layer called an overcoat is applied to prevent the photosensitive layer from contacting oxygen. Was a common means.

However, the method of attaching the cover sheet to the surface of the photosensitive material to prevent oxygen from coming into contact with the photosensitive layer requires an extra step of attaching the cover sheet to the surface of the photosensitive layer in manufacturing the photosensitive material. Also, when using the obtained light-sensitive material, light scattering occurs at the interface between the cover sheet and the light-sensitive layer at the time of exposure, resulting in deterioration of image quality. This is not a preferable method because it takes time and effort to peel off.

Further, a method of coating an overcoat layer on the surface of a light-sensitive material to prevent oxygen from contacting the light-sensitive layer is disclosed in a solvent which does not dissolve the light-sensitive layer, is transparent and has low oxygen permeability, and is used as a developer. Dissolve the soluble polymer and apply it on the photosensitive layer,
It is carried out by drying, and polyvinyl alcohol (PVA) is generally used as the polymer. This method also applies to the production of photosensitive materials.
There is a problem that equipment for performing multi-layer coating is required, and the overcoat coating liquid permeates into the photosensitive layer during coating to deteriorate the performance of the photosensitive layer.

A negative photosensitive lithographic printing plate using a photosensitive composition utilizing a photocuring reaction elutes an unexposed portion of a photosensitive layer with an alkaline aqueous solution containing an organic solvent in a developing treatment after exposure. The method of forming an image is common. However, when a developer containing an organic solvent is used, it is feared that the odor of the solvent may deteriorate the working environment of the plate making process and may adversely affect the health of the worker. Therefore, development of a negative lithographic printing plate that can be developed with an alkaline aqueous solution containing substantially no organic solvent has been desired.

Several proposals have been made for the negative type lithographic printing plates which can be developed with an alkaline aqueous solution containing substantially no organic solvent, and some of them have been put into practical use. However, since these photosensitive lithographic printing plates still have insufficient developability, the number of plates that can be treated with a certain amount of developing solution is small, or even when the developability is sufficient, when used for printing. However, there was a problem that the printing durability was insufficient.

[0008]

OBJECTS OF THE INVENTION Accordingly, a first object of the present invention is to provide a photosensitive composition and a photosensitive lithographic printing plate which have no sensitivity fluctuation due to a difference in oxygen concentration and do not require an oxygen barrier layer. is there.

A second object of the present invention is to provide a photosensitive composition and a photosensitive lithographic printing plate which can be developed with an alkaline aqueous solution containing substantially no organic solvent, have excellent developability and have sufficient printing durability. To provide.

[0010]

The above object of the present invention is represented by (1) one or more compounds selected from compounds represented by the following general formulas (I) and (II), and represented by the following general formula (III). A photosensitive composition comprising a compound, a polymerizable compound having an addition polymerizable unsaturated bond, and a polymer compound capable of forming a film.

[0011]

Embedded image [In the formula, R ¹ and R ² are each a methyl group, an ethyl group, and n-
It represents a propyl group, an isopropyl group, an n-butyl group, a sec.-butyl group, a tert.-butyl group, or a halogen. Both a and b represent the integer of 0-4. ]

[0012]

[Chemical 6] [In the formula, R ³ is an alkyl group having 1 to 15 carbon atoms, an aryl group, a hydroxy group, an alkoxy group, an aryloxy group,
It represents an alkylthio group, an arylthio group, a dialkylamino group, or halogen. c represents an integer of 0 to 2.

R ⁴ and R ⁵ each represent a hydrogen atom, an alkyl group, a hydroxy group, an alkoxy group or halogen,
Neither is a hydrogen atom. Further, R ⁴ and R ⁵ may be linked to each other to form a cyclic alkyl group.

R ⁶ represents a hydroxy group, a phenyl group, an alkyl-substituted phenyl group, an alkoxy-substituted phenyl group, a hydroxyphenyl group or a morpholino group. ]

[0015]

[Chemical 7] [In the formula, Ar represents a substituted or unsubstituted phenylene group, naphthylene group or aromatic heterocyclic group.

R ⁷ is a hydrogen atom, an alkyl group, an alkoxy group, a dialkylamino group, an alkylthio group, a hydroxy group, halogen, --COOR ⁸ , --O-(CH ₂ ) _g --CO.
_{^{OR 8, -O- (CH 2 C}} (R 9) HO) h R 8, -R 10 -
COOR ⁸ , -R ¹⁰ -CONHR ⁸ , -NHCOR ¹¹ (R
⁸ represents a hydrogen atom, an alkyl group, a substituted alkyl group, an aryl group, or a substituted aryl group. R ⁹ represents a hydrogen atom or a methyl group, R ¹⁰ represents an alkylene group, R ¹¹ represents an alkyl group, a substituted alkyl group, an alkoxy group, an aryl group or a substituted aryl group. g and h represent an integer of 1 to 10. ) Represents.

D represents an integer of 0-2. X represents halogen.

Although e and f represent integers of 0 to 3, e + f≤
It is within the range of 5. (2) The photosensitive composition as described in (1) above, which contains both the compounds represented by the general formulas (I) and (II). (3) The photosensitive composition as described in (1) or (2) above, which further contains a diazo compound. (4) The photosensitive composition as described in (3) above, wherein the diazo compound is a diazo compound containing a carboxyl group in the molecule. (5) The photosensitive composition as described in (1) to (4) above, wherein the film-forming polymer compound is a film-forming polymer compound having a phenolic hydroxyl group in the molecule. (6) The photosensitive compound as described in (1) to (5) above, wherein the polymerizable compound having an addition-polymerizable unsaturated bond is a compound represented by the following general formula (IV). .

[0019]

Embedded image [Wherein R ¹² , R ¹³ and R ¹⁴ are each independently CH
^{_{2 = C (R 15) CO}} (-OCH 2 CH 2) i - (R 15 represents a hydrogen atom or a methyl group, i is an integer from 0 to 3.) Represents a substituent represented by. (7) On a support having a hydrophilic surface, the above (1) to
A photosensitive lithographic printing plate, which is coated with the photosensitive composition as described in (6). (8) A method for developing a photosensitive lithographic printing plate, which comprises developing the photosensitive lithographic printing plate described in (7) above with an alkaline aqueous developer containing substantially no organic solvent. Therefore, it can be achieved.

In the present invention, a photosensitive composition containing a polymerizable compound having an addition polymerizable unsaturated bond and a polymer compound capable of forming a film is added to the compounds represented by the general formulas (I) and (II). A compound represented by the general formula (IV), in which one or more compounds selected from the above and the compound represented by the general formula (III) are added, and a polymerizable compound having an addition polymerizable unsaturated bond is added. By blending the diazo compound, the influence of oxygen on the inhibition of polymerization is reduced, but the reason for this is unknown.

The present invention will be described in detail below.

First, the polymerizable compound having an addition-polymerizable unsaturated bond will be described.

These polymerizable compounds having an addition polymerizable unsaturated bond are known, and the polymerizable compound having an addition polymerizable unsaturated bond used in the present invention may have any chemical structure. Good, but 2 in the molecule
Alternatively, a compound having an addition-polymerizable unsaturated bond of more than that is preferable.

Examples of the polymerizable compound having an addition-polymerizable unsaturated bond used in the present invention include unsaturated carboxylic acids, esters of unsaturated carboxylic acids and aliphatic polyhydroxy compounds, unsaturated carboxylic acids and aromatics. Examples thereof include esters with group polyhydroxy compounds, unsaturated carboxylic acids and polyvalent carboxylic acids, and esters obtained by the esterification reaction of the above-mentioned aliphatic polyhydroxy compounds and polyvalent hydroxy compounds such as aromatic polyhydroxy compounds. Specifically, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol triacrylate, hydroquinone described in JP-A-59-71048. Di (meth) acrylate, pyroga Roll triacrylate,
2,2-bis (4-acryloxydiethoxyphenyl)
Propane etc. are mentioned. In addition, (meth) acrylamides such as ethylenebis (meth) acrylamide, hexamethylenebis (meth) acrylamide, or
A vinyl urethane compound, an epoxy (meth) acrylate, etc. can be mentioned.

In the present invention, as a polymerizable compound having an addition-polymerizable unsaturated bond, or as a part thereof, a compound represented by the following general formula (IV) (hereinafter referred to as a compound of the general formula (IV) .) Is preferably used.

[0026]

[Chemical 9] [Wherein R ¹² , R ¹³ and R ¹⁴ are each independently CH
^{_{2 = C (R 15) CO}} (-OCH 2 CH 2) i - (R 15 represents a hydrogen atom or a methyl group, i is an integer from 0 to 3.) Represents a substituent represented by. The use of the compound of general formula (IV) has the effect of further reducing the sensitivity difference due to the influence of oxygen. At the same time, the stickiness of the surface of the photosensitive layer, which is a drawback of the photopolymerizable monomer, can be prevented.

Specific examples of the compound of the general formula (IV) used in the present invention include the followings.

[0028]

[Chemical 10] The compound of general formula (IV) may be used alone, or
Two or more compounds of general formula (IV) may be used in combination.

In the present invention, the amount of the polymerizable compound having an addition-polymerizable unsaturated bond used is usually 5 to 70% by weight, preferably 10% by weight based on the total solid content of the photosensitive composition.
~ 50% by weight.

The proportion of the compound of the general formula (IV) in the polymerizable compound having an addition-polymerizable unsaturated bond is preferably 20 to 100% by weight.

Next, the compound represented by the following general formula (I), the compound represented by the general formula (II) and the compound represented by the general formula (III) used in the present invention will be explained.

[0032]

[Chemical 11] [In the formula, R ¹ and R ² are each a methyl group, an ethyl group, and n-
It represents a propyl group, an isopropyl group, an n-butyl group, a sec.-butyl group, a tert.-butyl group, or a halogen. Both a and b represent the integer of 0-4. ]

[0033]

[Chemical 12] [In the formula, R ³ is an alkyl group having 1 to 15 carbon atoms, an aryl group, a hydroxy group, an alkoxy group, an aryloxy group,
It represents an alkylthio group, an arylthio group, a dialkylamino group, or halogen. c represents an integer of 0 to 2.

R ⁴ and R ⁵ each represent a hydrogen atom, an alkyl group, a hydroxy group, an alkoxy group, or halogen.
Neither is a hydrogen atom. Further, R ⁴ and R ⁵ may be linked to each other to form a cyclic alkyl group.

R ⁶ represents a hydroxy group, a phenyl group, an alkyl-substituted phenyl group, an alkoxy-substituted phenyl group, a hydroxyphenyl group or a morpholino group. ]

[0036]

[Chemical 13] [In the formula, Ar represents a substituted or unsubstituted phenylene group, naphthylene group or aromatic heterocyclic group.

R ⁷ is a hydrogen atom, an alkyl group, an alkoxy group, a dialkylamino group, an alkylthio group, a hydroxy group, halogen, --COOR ⁸ , --O-(CH ₂ ) _g --CO.
_{^{OR 8, -O- (CH 2 C}} (R 9) HO) h R 8, -R 10 -
COOR ⁸ , -R ¹⁰ -CONHR ⁸ , -NHCOR ¹¹ (R
⁸ represents a hydrogen atom, an alkyl group, a substituted alkyl group, an aryl group, or a substituted aryl group. R ⁹ represents a hydrogen atom or a methyl group, R ¹⁰ represents an alkylene group, R ¹¹ represents an alkyl group, a substituted alkyl group, an alkoxy group, an aryl group or a substituted aryl group. g and h represent an integer of 1 to 10. ) Represents.

D represents an integer of 0-2. X represents halogen.

Although e and f represent integers of 0 to 3, e + f≤
It is within the range of 5. Specific examples of the compound represented by the general formula (I) include the following.

[0040]

Embedded image Specific examples of the compound represented by formula (II) include the following.

[0041]

[Chemical 15]

[0042]

Embedded image Specific examples of the compound represented by the general formula (III) include the following.

[0043]

[Chemical 17]

[0044]

Embedded image

[0045]

[Chemical 19]

[0046]

Embedded image In the present invention, either one of the compound represented by the general formula (I) and the compound represented by the general formula (II) may be used, but it is preferable to use both of them.

In the present invention, other photopolymerization initiators can be used. These photopolymerization initiators are not particularly limited, and conventionally known ones used for photopolymerizable compositions can be used, for example, benzophenone, anthraquinone, Michler's ketone, oxadiazole-based compounds, complex system of biimidazole and Michler's ketone, Any complex system of a thioxanthone compound and an aromatic tertiary amine can be preferably used. Also, a sensitizer can be used in combination.

The amount of the photopolymerization initiator used is usually 0.5 to 30% by weight, more preferably 1 to 10% by weight, based on the total solid content of the photosensitive composition.

The film-forming polymer compound used in the present invention is preferably an alkali-soluble polymer compound, for example, a novolac resin, a polymer compound having a phenolic hydroxyl group in the molecule, JP-A-55-57.
Condensation resins of polyhydric phenols and aldehydes or ketones described in Japanese Patent No. 841 can be used. Among these, polymer compounds having a phenolic hydroxyl group in the molecule are particularly preferable.

Examples of the novolak resin include phenol / formaldehyde resin, cresol / formaldehyde resin, phenol / cresol / formaldehyde copolymer resin as described in JP-A-55-57841, and JP-A-55. Examples thereof include copolymer resins of p-substituted phenol and phenol or cresol and formaldehyde as described in JP-A-127553.

The molecular weight of the novolak resin (polystyrene standard) is preferably 3.00 × 10 ^{2 to} 7.5 in terms of number average molecular weight Mn.
0 × 10 ³ , weight average molecular weight Mw of 1.00 × 10 ^{3 to} 3.00 × 10 ⁴ ,
More preferably, Mn is 5.00 × 10 ^{2 to} 4.00 × 10 ³ , and Mw is 3.
It is 00 × 10 ^{3 to} 2.00 × 10 ⁴ .

The above novolak resins may be used alone or in combination of two or more kinds.

The above-mentioned polymer compound having a phenolic hydroxyl group in the molecule is a polymer compound containing a compound having an aromatic hydroxyl group in its side chain as a constituent unit in the molecule and soluble or swellable in alkaline water. These polymer compounds are, for example, vinyl monomers having an aromatic hydroxyl group in the side chain, specifically, o, m, p-hydroxyphenyl (meth) acrylamide, o, m, p-hydroxystyrene. , O, m, p-hydroxyphenyl (meth) acrylate, o, m, p-hydroxyphenylmaleimide, etc. and a vinyl monomer as shown in the following (a) to (k) can be obtained by copolymerization. . (A) Acrylic acid esters and methacrylic acid esters having an aliphatic hydroxyl group, for example, 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate, (b) acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, etc. α, β-unsaturated carboxylic acid,
(C) Methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, acrylic acid-
(Substituted) alkyl acrylates such as 2-chloroethyl, glycidyl acrylate and N-dimethylaminoethyl acrylate, (d) methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, cyclohexyl methacrylate, 4-hydroxybutyl methacrylate, glycidyl methacrylate. , (Substituted) alkyl methacrylates such as N-dimethylaminoethyl methacrylate,
(E) Acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N-ethylacrylamide, N-hexylmethacrylamide, N-cyclohexylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, N- Acrylamides or methacrylamides such as nitrophenyl acrylamide and N-ethyl-N-phenyl acrylamide, (f) ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether, phenyl vinyl ether and other vinyl ethers. (G) vinyl acetate, vinyl chloroacetate, vinyl butyrate, vinyl benzoate, etc. Glycol ester compounds, (h) styrene,
Styrenes such as α-methylstyrene, methylstyrene and chloromethylstyrene, (i) vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone and phenyl vinyl ketone, (j) ethylene, propylene, isobutylene, butadiene, The olefins such as isoprene, (k) N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, acrylonitrile, methacrylonitrile, and the like, and the polymer compound having a phenolic hydroxyl group in the molecule include the above monomer. You may copolymerize the other monomer which can be copolymerized with.

From the viewpoint of developability, among the polymer compounds having a phenolic hydroxyl group in the molecule, those containing the unsaturated carboxylic acid mentioned as the above (b) as a copolymerization component are preferable. The preferred acid value is 5 to 100, and the preferred molecular weight is 20,000 to 130,000.

The term "alkali-soluble" as used in the present invention means not only those which are soluble in alkaline water but also those which are swellable in alkaline water.

The amount of the polymer compound capable of forming a film is preferably 5 to 95% by weight based on the total solid content of the photosensitive composition.

When the diazo compound is added to the photosensitive composition of the present invention, the adhesion to the support can be improved, and the inhibition of polymerization due to oxygen can be reduced. Therefore, in the photosensitive composition of the present invention, It is preferable to add a diazo compound.

Examples of the diazo compound that can be used in the present invention include condensation resins of aromatic diazonium compounds and carbonyl compounds and salts of these condensation resins. These condensation resins have COO in their molecule.
A substituent having a substituent that imparts alkali solubility, such as H or SO ₃ H, particularly COOH, is preferable.

The diazo compound is contained in the photosensitive composition at 1 to
It is preferable to contain 20% by weight.

A dye may be further used in the photosensitive composition of the present invention. The dye is used for the purpose of obtaining a visible image by exposure (exposed visible image) and a visible image after development.

As the dye, those which change color tone by reacting with free radicals or acids can be preferably used.
Here, "the color tone changes" includes both the change of the color tone from colorless to colored, and the change of the color tone from colored to colorless or different colored. Preferred dyes are those which form a salt with an acid to change the color tone.

Examples of dyes that change from colored to colorless or to different colored tones include Victoria Pure Blue BOH (Hodogaya Chemical Co., Ltd.) and Oil Blue #.
603 [manufactured by Orient Chemical Industry Co., Ltd.], patent pure blue [manufactured by Sumitomo Sangoku Chemical Co., Ltd.], crystal violet, brilliant green, ethyl violet, methyl violet, methyl green, erythrosin B, basic fuchsin, malachite green, oil red, m-
Cresol purple, rhodamine B, auramine, 4-
triphenylmethane type, diphenylmethane type represented by p-diethylaminophenyliminonaphthoquinone, cyano-p-diethylaminophenylacetanilide and the like,
Oxazine, xanthene, iminonaphthoquinone,
Examples include azomethine-based or anthraquinone-based dyes.

On the other hand, examples of dyes that change from colorless to colored include, for example, leuco dyes and triphenylamine, diphenylamine, o-chloroaniline,
1,2,3-triphenylguanidine, naphthylamine, diaminodiphenylmethane, p, p'-bis-dimethylaminodiphenylamine, 1,2-dianilinoethylene, p, p ', p "-tris-dimethylaminotriphenylmethane, p, p'-bis-dimethylaminodiphenylmethylimine, p, p ', p "-triamino-o-
Methyltriphenylmethane, p, p′-bis-dimethylaminodiphenyl-4-anilinonaphthylmethane, p,
Examples thereof include primary or secondary arylamine dyes represented by p ′, p ″ -triaminotriphenylmethane.

Of these dyes, triphenylmethane dyes and diphenylmethane dyes are preferable, triphenylmethane dyes are more preferable, and Victoria Pure Blue BOH is particularly preferable.

The above dye is usually contained in the solid content of the photosensitive composition in an amount of 0.5 to 10% by weight, preferably about 1 to 5% by weight.

Various additives can be further added to the photosensitive composition of the present invention.

For example, alkyl ethers (eg, ethyl cellulose, methyl cellulose) for improving coating properties, fluorochemical surfactants and nonionic surfactants [eg Pluronic L-64 (manufactured by Asahi Denka Co., Ltd.) ],
A plasticizer for imparting flexibility and abrasion resistance to the coating film (eg, butylphthalyl, polyethylene glycol, tributyl citrate, diethyl phthalate, dibutyl phthalate,
Dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate, trioctyl phosphate, tetrahydrofurfuryl oleate, acrylic acid or methacrylic acid oligomers and polymers), oil sensitization for improving the oil sensitivity of the image area Agents (for example, JP-A-55-52)
No. 7 styrene-half-esterified product of alcohol of styrene-maleic anhydride copolymer), stabilizers (for example, phosphoric acid, phosphorous acid, organic acids (citric acid, oxalic acid,
Benzenesulfonic acid, naphthalenesulfonic acid, 4-methoxy-2-hydroxybenzophenone-5-sulfonic acid, tartaric acid, etc.), a development accelerator (eg, higher alcohol, acid anhydride, etc.) and the like. The amount of these additives added varies depending on the purpose of use, but is generally 0.01 to 30% by weight based on the total solid content of the photosensitive composition.

The photosensitive lithographic printing plate of the present invention is prepared by using the photosensitive composition of the present invention in a suitable solvent (propylene glycol monomethyl ether, propylene glycol monoethyl ether, methyl lactate, 4-hydroxy-2-butanone, methyl diglycol). , Methylcellosolve, ethylcellosolve, methylcellosolve acetate, acetone, methylethylketone, methanol, dimethylformamide, dimethylsulfoxide, water or a mixture thereof) to prepare a photosensitive composition coating solution, which is then used as a support. It can be obtained by coating on the above and drying to form a photosensitive layer.

The concentration of the photosensitive composition in the coating liquid is 1 to
It is desirable to set it in the range of 50% by weight.

For coating, conventionally known methods such as spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating and curtain coating can be used.

In this case, the coating amount of the photosensitive composition may be about 0.2 to 10 g / m ² in dry weight.

An overcoat layer can be provided on the photosensitive lithographic printing plate of the present invention. The overcoat layer can be formed by applying an aqueous solution of a water-soluble polymer on the photosensitive layer and drying.

As the support used in the above-mentioned photosensitive lithographic printing plate, paper, plastic (for example, polyethylene, polypropylene, polystyrene, etc.) laminated paper, aluminum (including aluminum alloy), zinc,
Metal plates such as copper, plastic films such as cellulose diacetate, cellulose triacetate, cellulose propionate, polyethylene terephthalate, polyethylene, polypropylene, polycarbonate polyvinyl acetal, etc. Paper on which the above metals are laminated or vapor deposited. Alternatively, a plastic film, a steel plate plated with aluminum or chrome, etc. may be mentioned, and among these, aluminum and an aluminum-coated composite support are particularly preferable.

Further, it is desirable that the surface of the aluminum material is roughened for the purpose of enhancing water retention and improving adhesion with the photosensitive layer.

Examples of the surface roughening method include generally known brush polishing method, ball polishing method, electrolytic etching, chemical etching, liquid honing, sand blasting and the like and combinations thereof, preferably brush polishing method,
Electrolytic etching, chemical etching and liquid honing are mentioned, of which the roughening method involving the use of electrolytic etching is particularly preferred. Further, as the electrolytic bath used in the electrolytic etching, an aqueous solution containing an acid, an alkali or a salt thereof or an aqueous solution containing an organic solvent is used, and among these, an electrolytic solution containing hydrochloric acid, nitric acid or a salt thereof is particularly used. Liquids are preferred. Further, the surface-roughened aluminum plate is desmutted with an acid or alkali aqueous solution, if necessary. The aluminum plate thus obtained is preferably anodized, and particularly preferably, a method of treating with a bath containing sulfuric acid or phosphoric acid can be mentioned. Further, if necessary, surface treatment such as treatment with an alkali silicate or hot water, or immersion in a water-soluble polymer compound or an aqueous solution of potassium fluorozirconate can be performed.

The photosensitive composition of the present invention does not vary in sensitivity in the presence of oxygen and can obtain high sensitivity even without using an oxygen barrier layer. On the layer of the organic composition, for example, a protective layer made of a polymer having an excellent oxygen barrier property such as polyvinyl alcohol, acidic celluloses, etc. is provided, and further, a polymerization inhibition effect by oxygen in the air is prevented. May be.

Conventional conventional methods are applied to the processing of the photosensitive lithographic printing plate of the present invention. That is, a negative relief image can be obtained with respect to the original image by exposing through a transparent original image having a line image, a halftone image and the like and then developing with an aqueous developer. As a source of active light suitable for exposure, a carbon arc lamp, a mercury lamp, a xenon lamp,
Examples include metal halide lamps and strobes.

The developer is not particularly limited, but particularly preferred is an alkaline aqueous solution containing substantially no organic solvent.

The phrase "substantially free of organic solvent" means that the organic solvent is not contained to the extent that it causes problems in hygiene and safety, and that it does not contain any organic solvent. is not. Generally, when the organic solvent contained in the developer composition is 1% by weight or less, these problems do not occur.

From the viewpoint of hygiene and safety, it is preferable that the content of the organic solvent contained in the developer composition is small, the content of the organic solvent is 0.5% by weight or less, more preferably the content of the organic solvent. It is not to contain at all.

Preferred alkali agents used in the developing solution of the present invention include, for example, potassium silicate, lithium silicate, sodium silicate, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium triphosphate, and secondary sodium silicate. Examples thereof include sodium phosphate, potassium triphosphate, dibasic potassium phosphate, sodium carbonate, potassium carbonate and the like.
Among these, a developer containing an alkali silicate such as potassium silicate, lithium silicate, or sodium silicate has the best development gradation and is most preferable.

In the present invention, the composition of the alkali silicate is [SiO ₂ ] / [M] = 0.5 to 1.5 (where [S
i0 ₂ ] and [M] represent the molar concentration of SiO ₂ and the total alkaline metal concentration, respectively. ) And SiO ₂
A developer containing 0.8 to 8% by weight is preferably used.

Further, the composition of alkali silicate is [SiO ₂ ] / [M] = 0.5 to 0.75 in molar ratio, and SiO ₂
A developer in which ₂ is 0.8 to 4% by weight is preferable in that the waste developer is easily neutralized due to its low concentration.
i0 ₂ ] / [M] = 0.75 to 1.3, and SiO ₂ is 1 to 8
A developer having a weight percent is preferable because it has a high buffering power and a high processing capacity.

The pH (25 ° C.) of the developing solution is preferably 12 or more, more preferably 12.5 to 14. Further, water-soluble sulfites such as sodium sulfite, potassium sulfite, lithium sulfite, and magnesium sulfite can be added to the developer. The preferred content of sulfite in the developer composition is 0.05 to 4% by weight.
And more preferably 0.1 to 1% by weight.

In the developer, anionic surfactants and amphoteric surfactants such as those described in JP-A-50-51324, JP-A-59-75255 and JP-A-60-111246 are also included. By containing at least one of the nonionic surfactants as described in JP-A-55-95946 and JP-A-56-142528, it is possible to improve the By including the molecular electrolyte, the wettability to the photosensitive layer can be enhanced and the gradation can be further enhanced. The amount of such a surfactant added is not particularly limited, but is preferably 0.003 to 3% by weight, and particularly preferably 0.006 to 1% by weight.

Further, it is preferable to use an alkali silicate containing 20 mol% or more of all alkali metals in the developing solution, since the generation of insoluble matter in the developing solution is reduced, and more preferably 90 mol% or more of potassium is used. That is the most preferable case is 100 mol% of potassium.

Further, the developer used in the present invention may contain an antifoaming agent. Suitable defoamers include organosilane compounds.

[0088]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Example An aluminum plate having a thickness of 0.3 mm is electrolytically surface-roughened in a hydrochloric acid aqueous solution, and then anodized in a sulfuric acid aqueous solution,
Hydrophilic treatment was performed using an aqueous solution of sodium silicate to obtain an aluminum support.

The resulting support was coated with a photosensitive composition coating solution having the composition shown in Table 1 below and dried to obtain photosensitive lithographic printing plate samples 1 to 4. At this time, the coating amount of the photosensitive composition coating liquid was set to be 1.6 g / m ² as a dry weight.

[0090]

[Table 1]

The materials listed in Table 1 are as follows. <Alkali-Soluble Acrylic Copolymer> The alkali-soluble acrylic copolymer is synthesized as follows.

125 ml of acetone and 125 ml of methanol were placed in a 500 ml four-necked flask equipped with a thermometer, a reflux condenser, a stirrer, a heating device and a nitrogen gas flow introduction pipe.
Add milliliters of mixed solvent, 9.0 g (0.09 mol) of ethyl acrylate, 34.2 g (0.30 mol) of ethyl methacrylate, 15.9 g (0.30 mol) of acrylonitrile as monomers.
Mol), methacrylic acid 0.86 g (0.01 mol) and 4-hydroxyphenylmethacrylamide 51.6 g (0.30 mol) were dissolved. Further, 3.28 g (0.02 mol) of azobisisobutyronitrile was dissolved as a polymerization initiator, and the mixture was heated under a nitrogen stream with vigorous stirring and refluxed at about 60 ° C. for 6 hours.

After completion of the reaction, the reaction solution was cooled to room temperature and then poured into water to precipitate a polymer compound. This was collected by filtration and vacuum dried at 50 ° C. for 24 hours to obtain 100 g of an alkali-soluble acrylic copolymer. The yield based on the total amount of monomers was 90%.

The weight average molecular weight of the obtained alkali-soluble acrylic copolymer was measured by gel permeation chromatography (GPC) with pullulan standard and N, N-dimethylformamide (DMF) solvent.
000.

<Diazo Resin 1> The diazo resin 1 is synthesized as follows.

In 200 g of ice-cooled concentrated sulfuric acid, 12.7 g (0.092 mol) of p-hydroxybenzoic acid and 40.5 g (0.138 mol) of 4-diazodiphenylamine sulfate were stirred while being careful not to let the liquid temperature exceed 5 ° C. Dissolve.

Next, 6.22 g of paraformaldehyde (0.
(207 mol) was slowly added over 1 hour with stirring to carry out a condensation reaction. Also in this case, care was taken so that the reaction liquid did not exceed 5 ° C. After adding paraformaldehyde, continue stirring at 5 ° C or lower for 30 minutes.

After completion of the reaction, the reaction solution was slowly added to 1600 ml of ethanol cooled to 0 ° C. to form a precipitate. At this time, care was taken so that the liquid temperature did not exceed 40 ° C. The precipitate was collected by suction filtration and washed with 300 ml of ethanol to obtain a reaction intermediate 1a (diazo resin sulfate).

After the reaction intermediate 1a taken out was dissolved in 240 ml of water and 19.04 g (0.14 mol) of zinc chloride dissolved in 90 ml of water was added, a precipitate was formed again. The precipitate is collected by suction filtration to give the reaction intermediate 1b.
(Diazo resin zinc chloride double salt) was obtained.

The reaction intermediate 1b taken out was dissolved in 1000 ml of water, and then 24.8 g (0.15 mol) of ammonium hexafluorophosphate dissolved in 180 ml of water was added to form a precipitate.

The precipitate was collected by suction filtration and washed with ethanol 30
After washing with 0 ml, it was dried at 30 ° C. for 3 days to obtain 32.4 g of diazo resin 1.

<Diazo Resin 2> The diazo resin 2 is synthesized by the following.

To 45.0 g of ice-cooled concentrated sulfuric acid, 14.65 g (0.05 mol) of 4-diazodiphenylamine sulfate was added at a liquid temperature of 5 ° C.
Dissolve with stirring, being careful not to exceed the value.

Then, paraformaldehyde 1.05 g (0.
(035 mol) was slowly added over 1 hour with stirring to carry out a condensation reaction. Also in this case, care was taken so that the reaction liquid did not exceed 5 ° C. After adding paraformaldehyde, continue stirring at 5 ° C or lower for 30 minutes.

After completion of the reaction, the reaction solution is slowly added to 400 ml of ethanol cooled to 0 ° C. to form a precipitate. At this time, care was taken so that the liquid temperature did not exceed 40 ° C. The precipitate was collected by suction filtration and washed with 100 ml of ethanol to obtain a reaction intermediate 2a (diazo resin sulfate).

The reaction intermediate 2a taken out was dissolved in 100 ml of water, and then 6.81 g (0.05 mol) of zinc chloride dissolved in 30 ml of water was added to again form a precipitate. The precipitate was collected by suction filtration to obtain a reaction intermediate 2b (diazo resin zinc chloride double salt).

The reaction intermediate 2b taken out was dissolved in 200 ml of water, and then 8.15 g (0.05 mol) of ammonium hexafluorophosphate dissolved in 40 ml of water was added to form a precipitate.

The precipitate was collected by suction filtration and washed with ethanol 10
After washing with 0 ml, it was dried at 30 ° C. for 3 days to obtain 11.1 g of diazo resin 2. <Kayakyu DETX>

[0109]

[Chemical 21] <Bistrihalomethyl-s-triazine compound>

[0110]

[Chemical formula 22] <Irgacure 651>

[0111]

[Chemical formula 23] <Fluorosurfactant> Megafac F-177 [manufactured by Dainippon Ink and Chemicals, Inc.] Using film originals containing step tablets in the obtained samples 1 to 4 and a metal halide lamp of 2 kW, 60
Exposure was carried out for 30 seconds from a distance of cm, and development processing was carried out with a developer having the following composition to obtain a lithographic printing plate. The exposure was performed under two conditions: under vacuum and in air. <Developer composition> A Potassium silicate 1160 g Caustic potash 133 g Water 5133 ml (pH = 12.7) Printing was carried out using the obtained lithographic printing plate, and the sensitivity, printing durability and running solution developability were evaluated by the following evaluation methods. I went. The obtained results are shown in Table 2.

<< Evaluation Method >><Evaluation of Sensitivity> The number of gray scale steps in which the obtained gray scale developed image was completely solid was determined, and the sensitivity was evaluated by the number of steps. The larger the number of stages, the higher the sensitivity.

<Evaluation of Printing Durability> Printing is performed until the image portion on the printing plate is abraded or peeled off and the ink portion on the printed material appears defective in ink, and the number of printed sheets by that time is obtained. The printing durability was evaluated.

<Evaluation of developability of running solution> After developing 10 m ² of unexposed samples 1 to 4 with 1 liter of the above-mentioned developing solution, the image-exposed sample was further developed to obtain a printing plate, and the printing plate was printed. Printing was performed using a plate, and stains on the print were confirmed.

[0115]

[Table 2]

[0116]

EFFECTS OF THE INVENTION The photosensitive composition and the photosensitive lithographic printing plate of the present invention have no sensitivity fluctuation due to a difference in oxygen concentration, and substantially contain an organic solvent even if an oxygen barrier layer is not provided. It can be developed with an alkaline aqueous solution, has excellent developability, and has excellent printing durability.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication location G03F 7/32 (72) Inventor Noriyuki Kizu 1 Sakura-cho, Hino-shi, Tokyo Konica Stock Company (72 ) Inventor Naruo Tsuji 1000 Kamoshida-cho, Aoba-ku, Yokohama-shi, Kanagawa Mitsubishi Chemical Corporation Yokohama Research Institute (72) Inventor Fumiyuki Matsuo 1000, Kamoshida-cho, Aoba-ku Yokohama, Kanagawa Mitsubishi Chemical Corporation Yokohama Research Institute

Claims (8)

[Claims] 1. One or more compounds selected from compounds represented by the following general formulas (I) and (II):
A photosensitive composition comprising a compound represented by I), a polymerizable compound having an addition polymerizable unsaturated bond, and a polymer compound capable of forming a film. Embedded image [In the formula, R ¹ and R ² are each a methyl group, an ethyl group, and n-
It represents a propyl group, an isopropyl group, an n-butyl group, a sec.-butyl group, a tert.-butyl group, or a halogen. Both a and b represent the integer of 0-4. ] [Chemical 2] [In the formula, R ³ is an alkyl group having 1 to 15 carbon atoms, an aryl group, a hydroxy group, an alkoxy group, an aryloxy group,
It represents an alkylthio group, an arylthio group, a dialkylamino group, or halogen. c represents an integer of 0 to 2. R ⁴ ,
R ⁵ is a hydrogen atom, an alkyl group, a hydroxy group,
Represents an alkoxy group and halogen, but neither is a hydrogen atom. Further, R ⁴ and R ⁵ may be linked to each other to form a cyclic alkyl group. R ⁶ represents a hydroxy group, a phenyl group, an alkyl-substituted phenyl group, an alkoxy-substituted phenyl group, a hydroxyphenyl group, or a morpholino group. ] [Chemical 3] [In the formula, Ar represents a substituted or unsubstituted phenylene group, naphthylene group or aromatic heterocyclic group. R ⁷ is a hydrogen atom, an alkyl group, an alkoxy group, a dialkylamino group, an alkylthio group, a hydroxy group, a halogen, —CO
_{^{OR 8, -O- (CH 2)}} g -COOR 8, -O- (CH 2
_{^{C (R 9) HO) h}} R 8, -R 10 -COOR 8, -R 10 -C
ONHR ⁸ , —NHCOR ¹¹ (R ⁸ represents a hydrogen atom, an alkyl group, a substituted alkyl group, an aryl group or a substituted aryl group. R ⁹ is a hydrogen atom or a methyl group, R ¹⁰ is an alkylene group, R ¹¹ is an alkyl group, Represents a substituted alkyl group, an alkoxy group, an aryl group and a substituted aryl group, and g and h represent an integer of 1 to 10). d represents an integer of 0 to 2. X represents halogen. e and f represent an integer of 0 to 3, but are within the range of e + f ≦ 5. ] 2. The photosensitive composition according to claim 1, which contains both the compounds represented by the general formulas (I) and (II). 3. The photosensitive composition according to claim 1, further comprising a diazo compound. 4. The photosensitive composition according to claim 3, wherein the diazo compound is a diazo compound having a carboxyl group in the molecule. 5. The photosensitive composition according to claim 1, wherein the film-forming polymer compound is a film-forming polymer compound having a phenolic hydroxyl group in the molecule. 6. The photosensitive composition according to claim 1, wherein the polymerizable compound having an addition-polymerizable unsaturated bond is a compound represented by the following general formula (IV). [Chemical 4] [Wherein R ¹² , R ¹³ and R ¹⁴ are each independently CH
^{_{2 = C (R 15) CO}} (-OCH 2 CH 2) i - (R 15 represents a hydrogen atom or a methyl group, i is an integer from 0 to 3.) Represents a substituent represented by. ] 7. A photosensitive lithographic printing plate comprising the support having a hydrophilic surface and the photosensitive composition according to claim 1 coated on the support. 8. The photosensitive lithographic printing plate according to claim 7,
A method for developing a photosensitive lithographic printing plate, which comprises developing with an alkaline aqueous developer containing substantially no organic solvent.