JPH1138629A - Lithographic printing plate with positive photosensitive layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive photosensitive layer for the lithographic printing plate good in resistance to residual color, stains caused by leaving alone and whitening and in printing resistance. SOLUTION: This lithographic printing plate is provided on an aluminum supporting body subjected to hydrophilicity-enhancing treatment with an interlayer containing a polymer having a repeating unit represented by the formula and with a positive photosensitive layer on the interlayer. In the formula, A is an aromatic, -COO-, -CONH- or -CON(CH3 )- group; L is a divalent bonding group; R1 is an H or halogen atom or an alkyl group: and X is an acid group having a pKa of <=7 or its alkali metal salt or an ammonium salt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive lithographic printing plate, and more particularly to a positive photosensitive lithographic printing plate.

[0002]

2. Description of the Related Art Conventionally, a positive type photosensitive lithographic printing plate widely used is a positive type lithographic printing plate comprising an o-quinonediazide compound on an aluminum support which has been subjected to surface roughening treatment, alkali etching or anodic oxidation treatment. It is provided with a photosensitive layer. It is known that an o-quinonediazide compound changes to a carboxylic acid upon exposure to ultraviolet light,
When developed with an aqueous alkali solution after image exposure, only the exposed portions of the photosensitive layer are dissolved and removed, and the surface of the support is exposed. Therefore, the unexposed portion (image portion) becomes an ink receiving portion because the lipophilic photosensitive layer remains, and the exposed portion (non-image portion) retains water because the hydrophilic support surface is exposed. Become a rebound part. However, the aluminum support surface has insufficient hydrophilicity, so that the ink repulsion is insufficient, and there has been a problem that ink adheres to non-image areas (hereinafter referred to as stain performance). Therefore, usually for the purpose of improving the stain performance,
It is necessary to make the non-image area hydrophilic. However, generally, when a positive photosensitive layer is provided on a support subjected to hydrophilization treatment, adhesion between the hydrophilic support surface and the lipophilic photosensitive layer is poor,
There is a problem that the number of sheets that can be printed normally decreases (hereinafter referred to as printing durability). Therefore, by using an alkali developer containing a silicate such as sodium silicate or potassium silicate at the time of development, a hydrophilic silicate film is formed on the non-image area support at the time of development. Only the part was hydrophilized. Therefore, usually, by using an alkali developer containing a silicate such as sodium silicate or potassium silicate as a developer, a hydrophilic silicate film is formed on the non-image area support during development. The non-image area was made hydrophilic. However,
When a developer containing a silicate is used, solids due to SiO ₂ are likely to precipitate, or when a waste solution is treated, a gel due to SiO ₂ is generated when a neutralization treatment is attempted. There was a problem.

Therefore, even if a positive photosensitive layer is provided on a support whose surface has been subjected to hydrophilic treatment in advance, there has been a demand for a technique in which the adhesion between the support and the photosensitive layer is good and the printing durability is not deteriorated.

Further, a printing plate having a photosensitive layer provided on a substrate subjected to an anodized film treatment is used in a pH range of 10 to 1 containing no silicate.
When developing with an alkali developing solution of about 4, there is also a problem that the non-image area becomes white with the dissolution of the anodic oxide film.
Further, there is another problem that the anodized film that dissolves at this time is accumulated in the developing solution to generate scum and sludge. Further, if the plate is left unattended during printing, there is a problem that it is difficult to remove ink from the non-image area. Such a phenomenon is called “dirt”. Furthermore, even in a developer containing a silicate, the substance contained in the photosensitive layer is irreversibly adsorbed on the non-image area of the lithographic printing plate obtained by development, and the non-image area is contaminated. (The dye added to the photosensitive layer is
There is also a problem that it is difficult to discriminate between the image area and the non-image area.

Conventionally, various treatments have been proposed for the anodic oxide film on the support. The steam treatment, which is said to have an effect of preventing dissolution in the developer, could prevent the whitening of the non-image area, but could not solve the problem of standing stains. On the other hand, if the anodic oxide film is treated with silicate, the problems of whitening of the non-image area and stains on standing can be solved, but the support on the image area is also hydrophilized by the silicate treatment, so that lipophilic photosensitive The adhesion to the layer becomes poor, and the printing durability (the number of sheets that can be printed normally when printing) deteriorates.

In order to solve the above problems, US Pat. No. 3,136,636 proposes to provide an intermediate layer of a water-soluble polymer such as polyacrylic acid and carboxymethylhydroxyethylcellulose. However, it was still unsatisfactory in terms of printing durability. In U.S. Pat. No. 4,483,913,
It has been proposed to provide an intermediate layer of a quaternary ammonium compound such as poly (dimethyldiallylammonium chloride), but the stain performance was insufficient and unsatisfactory. Further, a positive lithographic printing plate having a positive photosensitive layer provided on a support whose surface has been subjected to hydrophilic treatment in advance has insufficient residual color, and improvement thereof has been desired.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a non-image area which is not whitened, is less likely to generate sludge and scum, and is free from uncleanness when left in image processing. An object of the present invention is to provide a positive photosensitive lithographic printing plate having good printing performance. Another object of the present invention is to provide a positive photosensitive lithographic printing plate in which residual colors are reduced or eliminated. Furthermore, the object of the present invention is to provide a positive-working type which has a good printing durability without leaving white non-image areas even when developed using a developer containing no silicate, and which does not cause standing stains and residual colors. An object of the present invention is to provide a photosensitive lithographic printing plate.

[0008]

Means for Solving the Problems As a result of intensive studies, the present inventors have solved the above object by the following photosensitive lithographic printing plate. That is, the present invention provides an intermediate layer containing a polymer compound containing a repeating unit represented by the following general formula (1) on an aluminum support subjected to a hydrophilic treatment, and further comprises a positive photosensitive layer This is achieved by a positive photosensitive lithographic printing plate characterized by the following.

[0009]

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Wherein A is an aromatic group, a —COO— group,
Represents a CONH- group or a -CON (CH ₃ )-group, L represents a divalent linking group, R ₁ represents a hydrogen atom, a halogen atom,
X represents an alkyl group, and X represents an acid group having a pKa of 7 or less, or an alkali metal salt or an ammonium salt thereof. )

In the present invention, by subjecting the surface of the support to a hydrophilic treatment such as a silicate treatment in advance, whitening of the non-image area, generation of stain on standing, and generation of sludge and scum due to dissolution of the anodic oxide film are achieved. Could be prevented. Furthermore, surprisingly,
By providing an intermediate layer containing a polymer compound containing a monomer represented by the general formula (1) as a structural unit on a hydrophilically-treated support, the adhesion between the support and the photosensitive layer is improved. As a result, the printing durability was improved. On the other hand, in the non-image area, the acid group separated from the main chain in the polymer compound is neutralized by the alkali developer and easily dissociated, so that the polymer compound is dissolved and removed from the surface of the support. Therefore,
In the non-image area, the surface of the support subjected to the hydrophilization treatment by the development treatment was exposed, so that the stain performance was also good.
Since the lithographic printing plate of the present invention can use a developing solution containing no silicate, the generation of sludge and scum associated with the silicate was also improved. Furthermore, surprisingly, the residual color performance and the whitening prevention performance of the substrate were extremely good.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the polymer compound used for forming the intermediate layer of the present invention will be described in detail. The polymer compound of the present invention is a polymer compound containing the monomer represented by the general formula (1) as a constituent unit. Among the polymer compounds of the present invention, preferably, a polymer characterized in that the main chain structure of the polymer compound is a vinyl-based polymer such as an acrylic resin, a methacrylic resin, or polystyrene, or a urethane resin, a polyester, or a polyamide. It is. More preferably, the polymer is characterized in that the main chain structure of the polymer compound is a vinyl-based polymer such as an acrylic resin, a methacrylic resin, or polystyrene. Particularly preferred is a homopolymer or copolymer containing the monomer represented by the general formula (1) as a constituent unit.

In the above general formula (1), A represents
Or unsubstituted aromatic group, -COO- group, -CONH- group
Or -CON (CH_Three )-Represents a group. Replacement or nothing
The substituted aromatic group is preferably a phenylene group
Or a substituted phenylene group, and the substituent is a hydroxyl group,
Mino group, alkoxy group, halogen atom or alkyl
Group. More preferably, a phenylene group or a substituted phenyl group is used.
Represents a phenylene group, the substituent of which is hydroxyl, amino
Group, an alkoxy group having 1 to 3 carbon atoms or 1 to 3 carbon atoms
Is an alkyl group. Particularly preferred is phenyle
Group. L represents an alkylene group or a molecular formula of C_xH
_2xO, C_xH_2xS or C_xH_{2x + 1}N-valent
A linking group (where x represents an integer of 0 to 12) or
Represents a divalent linking group which may be substituted. More preferably charcoal
Linked by an alkylene group of 1 to 2 or an oxygen atom
Represents an alkylene group having 1 to 2 carbon atoms. May be replaced
In the divalent linking group, preferred substituents are
) Alkyl group, nitrile group, -COOR_Two , -CON
R_Three R_Four Or -COR_Five Where R_Two ~ R_Five 
Are each independently a hydrogen atom, an alkyl group, a substituted
Represents an aromatic group, an aromatic group or a substituted aromatic group,
Preferably, an alkyl group having 1 to 4 carbon atoms, a nitrile group, -C
OOR_Two , -CONR_Three R_Four Or -COR_Five The table
And where R_Two~ R_Five Are each independently a hydrogen atom,
It is a alkyl group or an alkyl group having 1 to 4 carbon atoms. Change
More preferably, a methyl group, an ethyl group, a nitrile group or
Is -COOR_Two Where R_Two Is more specifically water
Elemental atom, methyl group and ethyl group. X has a pKa of 7 or less
The following acid group or its alkali metal salt or ammonium
, Preferably -COOH, -SO_Three H,
-OSO_Three H, -PO_Three H _Two , -OPO_Three H_Two ,
And more preferably -COOH, -PO_Three H_Two Or
-OPO_Three H_Two And particularly preferably -COOH.
You. R₁ Represents a hydrogen atom, an alkyl group or a halogen atom
But preferably a hydrogen atom, chlorine atom or carbon number
Represents an alkyl group of 1 to 4, more preferably a hydrogen atom
Or a methyl group.

Specific examples of the monomer represented by the general formula (1) are shown below. However, these do not limit the content of the present invention.

[0015]

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[0016]

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[0017]

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[0018]

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[0019]

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[0020]

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In the polymer compound used in the present invention,
It is desirable that the compound (constituent unit) represented by the general formula (1) be contained in an amount of 20 mol% or more, preferably 40 mol% or more. If it is less than 20 mol%, dissolution and removal during alkali development are insufficient, and adhesion to both the surface of the aluminum support and the photosensitive layer is insufficient, which is not suitable. Further, the components represented by the general formula (1) may be used alone or in combination of two or more. Further, as the polymer compound according to the present invention, two or more kinds of compounds having different constitutional units, composition ratios or molecular weights may be used in combination. Next, typical examples of the polymer compound used in the present invention are shown below. The composition ratio of the polymer structure represents a mole percentage.

[0022]

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[0023]

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[0024]

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[0025]

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[0026]

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[0027]

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[0028]

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The polymer compound according to the present invention generally comprises
It can be produced using a radical chain polymerization method (“Textbook of Polymer Science” 3rd ed, (1984) FW
See Billmeyer, A Wiley-Interscience Publication).
Although the molecular weight of the polymer compound according to the present invention may be in a wide range, the weight average molecular weight (Mw) is preferably from 500 to 2,000,000 when measured using a light scattering method. More preferably, it is in the range of 2,000 to 600,000. Further, the amount of unreacted monomer contained in the polymer compound may be wide,
wt% or less, and more preferably 10 Wt% or less.

Next, a synthesis example of the polymer compound according to the present invention will be described. [Synthesis Example] Vinylphenylacetic acid homopolymer (m / p ratio: about 2 /
No. 1) [No. Synthesis of P-1] Vinylphenylacetic acid (m / p ratio: mixture of about 2/1) 1
62.2 g (1.0 mol) and 378 g of 2-methoxyethanol were placed in a 500 ml three-necked flask and heated to 75 ° C. while stirring under a nitrogen stream. Then 2,
2.30 g of 2-azobis (isobutyric acid) dimethyl (10 m
mol) was added and stirring continued. After 2 hours, 2.30 g (10 mmo) of dimethyl 2,2-azobis (isobutyrate)
l) was added. Two hours later, 2.30 g (10 mmol) of dimethyl 2,2-azobis (isobutyrate) was added. After stirring for 2 hours, the mixture was allowed to cool to room temperature. The reaction solution was poured into 4 L of water with stirring. The precipitated solid was collected by filtration and dried. The yield was 151 g. The obtained solid was measured for molecular weight by a light scattering method, and as a result, the weight average molecular weight (Mw) was 28,000. Other polymer compounds according to the present invention are synthesized in a similar manner.

The intermediate layer of the polymer compound according to the present invention is provided by applying various methods on an aluminum plate which has been subjected to a hydrophilic treatment described later.

This layer can be provided by the following method. A method in which a solution in which the polymer compound according to the present invention is dissolved in an organic solvent such as methanol, ethanol, and methyl ethyl ketone or a mixed solvent thereof or a mixed solvent of these organic solvents and water is coated on an aluminum plate, and dried and provided. An aluminum plate is immersed in an organic solvent such as methanol, ethanol, methyl ethyl ketone, or a mixed solvent of these organic solvents and water, or a solution obtained by dissolving the polymer compound of the present invention in a mixed solvent thereof to adsorb the polymer compound. After that, it is a method of providing an organic intermediate layer by washing and drying with water or the like. In the former method, a solution of the polymer compound having a concentration of 0.005 to 10% by weight can be applied by various methods. For example, any method such as bar coater coating, spin coating, spray coating, and curtain coating may be used. In the latter method, the concentration of the solution is 0.01 to 20% by weight, preferably 0.05 to 5% by weight, and the immersion temperature is 20 to 90 ° C.
Preferably, the temperature is 25 to 50 ° C., and the immersion time is 0.1 second to
20 minutes, preferably 2 seconds to 1 minute. The above solution is
Basic substances such as ammonia, triethylamine and potassium hydroxide; inorganic acids such as hydrochloric acid, phosphoric acid, sulfuric acid and nitric acid; organic sulfonic acids such as nitrobenzenesulfonic acid and naphthalenesulfonic acid; organic phosphonic acids such as phenylphosphonic acid; benzoic acid PH is adjusted with various organic acidic substances such as organic carboxylic acids such as acid, coumaric acid and malic acid, and organic acid chlorides such as naphthalenesulfonyl chloride and benzenesulfonyl chloride;
2, more preferably in the range of pH = 0 to 5. Further, a yellow dye can be added for improving the tone reproducibility of the photosensitive lithographic printing plate. The coating amount of the polymer compound of the present invention after drying is ^{2 to} 100 mg / m ^2.
Is suitable, and preferably 5 to 50 mg / m ² .
If the coating amount is less than 2 mg / m ² , a sufficient effect cannot be obtained. The same is true even when the amount is more than 100 mg / m ² .

Next, the positive photosensitive lithographic printing plate of the present invention will be described in detail in the order of (1) the support, (2) the photosensitive composition, and (3) the developing treatment. In the present invention, the photosensitive lithographic printing plate may be a PS plate.

<1> Support The support used in the positive photosensitive lithographic printing plate of the present invention and the processing thereof will be described below. (Aluminum Plate) The aluminum plate used in the present invention is a plate-like body such as pure aluminum or an aluminum alloy containing aluminum as a main component and containing a small amount of a different atom. The hetero atoms include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, titanium and the like. The synthetic composition has a heteroatom content of 10% by weight or less. Aluminum which is suitable for the present invention is pure aluminum. However, since pure aluminum is difficult to produce due to refining technology, it is preferable that aluminum contains as little foreign atoms as possible. In addition, any aluminum alloy having the above-described heteroatom content can be said to be a material that can be used in the present invention. As described above, the composition of the aluminum plate used in the present invention is not particularly limited, and conventionally known and publicly available materials can be appropriately used. Preferred materials include JIS A 10
50, 1100, 1200, 3003, 310
3, the same 3005 materials are included. The thickness of the aluminum plate used in the present invention is about 0.1 mm to 0.6 mm. Prior to the surface roughening treatment of the aluminum plate, a degreasing treatment for removing a rolling oil on the surface, for example, a treatment with a surfactant or an alkaline aqueous solution is performed as necessary.

(Roughening Treatment and Anodizing Treatment) As methods for roughening the surface of an aluminum plate, there are a method of mechanically roughening, a method of electrochemically dissolving and roughening the surface, and a method of chemically roughening. There is a method of selectively dissolving the surface. As a mechanical method, a known method called a ball polishing method, a brush polishing method, a blast polishing method, a buff polishing method, or the like can be used. Further, as an electrochemical surface roughening method, there is a method of performing an alternating or direct current in a hydrochloric acid or nitric acid electrolyte. Further, as disclosed in JP-A-54-63902, a method in which both are combined can also be used. The aluminum plate thus roughened is subjected to an alkali etching treatment and a neutralization treatment as necessary, and then subjected to an anodic oxidation treatment in order to increase the water retention and abrasion resistance of the surface. As the electrolyte used for the anodic oxidation treatment of the aluminum plate, any electrolyte can be used as long as it forms a porous oxide film. In general, sulfuric acid, phosphoric acid, oxalic acid, chromic acid, or a mixed acid thereof is used. The concentration of these electrolytes is appropriately determined depending on the type of the electrolyte. The anodizing treatment conditions vary depending on the electrolyte used, and thus cannot be specified unconditionally.
0 ° C., current density 5-60 A / dm ² , voltage 1-100 V,
An electrolysis time of 10 seconds to 5 minutes is appropriate. The amount of the anodized film is suitably 1.0 g / m ² or more, but more preferably in the range of 2.0 to 6.0 g / m ^2. When the anodic oxide film is less than 1.0 g / m ² , the printing durability is insufficient or the non-image portion of the lithographic printing plate is easily damaged,
So-called "scratch stains" in which ink adheres to scratches during printing are likely to occur. In addition, such an anodizing treatment is applied to the surface used for printing the support of the lithographic printing plate, and the back surface of the electric force lines causes a 0.01 to 3 g / m ² anodic oxide film on the back surface. It is generally formed.

(Hydrophilization treatment) As the hydrophilization treatment used after the above-mentioned treatment, there is conventionally known:
A hydrophilic treatment is used. Examples of such a hydrophilic treatment include U.S. Pat. Nos. 2,714,066 and 3,181.
No. 461, No. 3,280,734, No. 3,902,7
No. 34 discloses an alkali metal silicate (for example, sodium silicate aqueous solution) method. In this method, the support is immersed or electrolytically treated in an aqueous solution of sodium silicate. Alternatively, Japanese Patent Publication No. 36-22
No. 063, and potassium fluoride zirconate disclosed in U.S. Pat. Nos. 3,276,868 and 4,153.
For example, a method of treating with polyvinyl phosphonic acid as disclosed in U.S. Pat. No. 461 and 4,689,272 is used. Among these, a particularly preferred hydrophilic treatment in the present invention is a silicate treatment. The silicate treatment will be described below.

(Silica treatment) The anodic oxide film of the aluminum plate treated as described above was treated with an alkali metal silicate of 0.1 to 30% by weight, preferably 0.5 to 10% by weight, at 25 ° C. Is immersed in an aqueous solution having a pH of 10 to 13 at, for example, 15 to 80 ° C. for 0.5 to 120 seconds. If the pH of the alkali metal silicate aqueous solution is lower than 10, the solution will gel, and if it is higher than 13.0, the oxide film will be dissolved. As the alkali metal silicate used in the present invention, sodium silicate, potassium silicate, lithium silicate and the like are used. Hydroxides used to increase the pH of the aqueous alkali metal silicate solution include sodium hydroxide, potassium hydroxide and lithium hydroxide. In addition, an alkaline earth metal salt or a Group IVB metal salt may be added to the above-mentioned processing solution. Alkaline earth metal salts include nitrates such as calcium nitrate, strontium nitrate, magnesium nitrate, barium nitrate, sulfates, hydrochlorides, phosphates,
Water-soluble salts such as acetate, oxalate, and borate are exemplified. Group IVB metal salts include titanium tetrachloride, titanium trichloride, potassium titanium fluoride, titanium potassium oxalate, titanium sulfate, titanium tetraiodide, zirconium chloride, zirconium dioxide, zirconium oxychloride, zirconium tetrachloride and the like. Can be. Alkaline earth metal salts or Group IVB metal salts can be used alone or in combination of two or more. The preferred range of these metal salts is 0.01 to 10% by weight, and the more preferred range is 0.05 to 5.0% by weight. By silicate treatment,
Because the hydrophilicity on the aluminum plate surface is further improved,
At the time of printing, the ink hardly adheres to the non-image area, and the stain performance is improved.

(Backcoat) On the back surface of the support, a backcoat is provided if necessary. Examples of the back coat include a coating comprising a metal oxide obtained by hydrolyzing and polycondensing an organic polymer compound described in JP-A-5-45885 and an organic or inorganic metal compound described in JP-A-6-35174. Layers are preferably used. Among these coating layers, Si (OCH ₃ ) ₄ , Si
(OC ₂ H ₅ ) ₄ , Si (OC ₃ H ₇ ) ₄ , Si (OC ₄ H ₉ )
Silicon alkoxy compounds such as ₄ are inexpensive and easily available,
A coating layer of a metal oxide provided therefrom is particularly preferred because of its excellent development resistance.

<2> Photosensitive Composition Next, the photosensitive composition used in the photosensitive lithographic printing plate of the present invention will be described in detail. As the photosensitive composition used in the present invention, any one can be used as long as its solubility in a developer or swelling property changes before and after exposure. Hereinafter, typical photosensitive compositions will be described, but the invention is not limited thereto.

The photosensitive compound of the photosensitive composition includes o
-Quinonediazide compound, and a typical example thereof is an o-naphthoquinonediazide compound. Examples of the o-naphthoquinonediazide compound include JP-B-43-28.
Preferred is an ester of 1,2-diazonaphthoquinonesulfonic acid chloride and pyrogallol-acetone resin described in JP-A-403-403.

Other suitable o-quinonediazide compounds include, for example, US Pat.
There is an ester of 1,2-diazonaphthoquinone sulfonic acid chloride and phenol formaldehyde resin described in 188,210.

Other useful o-naphthoquinonediazide compounds include those reported and known in numerous patents. For example, JP-A-47-5303
No. 48-63802, No. 48-63803, No. 48-96575, No. 49-38001, No. 48-
13354, JP-B-37-18015, 41-1
No. 1222, No. 45-9610, No. 49-17481
JP-A-5-11444, JP-A-5-19477
JP-A-5-19478, JP-A-5-107755
No. 2,797,213 and No. 3,45.
No. 4,400, No. 3,544,323, No. 3,5
No. 73,917, No. 3,674,495, No. 3,
785,825, British Patent No. 1,227,602,
Nos. 1,251,345 and 1,267,005
No. 1,329,888, No. 1,330,93
No. 2, German Patent No. 854,890, and the like.

As another o-quinonediazide compound, an o-naphthoquinonediazide compound obtained by reacting a polyhydroxy compound having a molecular weight of 1,000 or less with 1,2-diazonaphthoquinonesulfonic acid chloride can be used. For example, JP-A-51-13940
No. 2, No. 58-150948, No. 58-203434
No., 59-165053, 60-12445
No. 60-134235, No. 60-16343
No. 61-118744, No. 62-10645,
No. 62-10646, No. 62-153950, No. 6
2-178562, 64-76047, U.S. Pat. Nos. 3,102,809 and 3,126,281,
No. 3,130,047, No. 3,148,983
No. 3,184,310, No. 3,188,21
No. 0, No. 4,639, 406, and the like, and those described in each gazette or specification.

When synthesizing these o-naphthoquinonediazide compounds, it is preferable to react 0.2 to 1.2 equivalents of 1,2-diazonaphthoquinonesulfonic acid chloride with respect to the hydroxyl groups of the polyhydroxy compound. More preferably, the reaction is performed in an amount of 0.3 to 1.0 equivalent. As the 1,2-diazonaphthoquinone sulfonic acid chloride, 1,2-diazonaphthoquinone-5-sulfonic acid chloride is preferable, but 1,2-diazonaphthoquinone-sulfonic acid chloride is preferred.
4-sulfonic acid chloride can also be used. The obtained o-naphthoquinonediazide compound is a mixture of various compounds having different positions and introduced amounts of 1,2-diazonaphthoquinonesulfonic acid ester groups. The ratio of the compound in the mixture (content of the completely esterified compound) is preferably 5 mol% or more, more preferably 20 to 99 mol%.

Further, as a photosensitive compound which acts positively without using an o-naphthoquinonediazide compound, for example, a polymer compound containing an o-nitrile carbinol ester group described in JP-B No. 52-2696 or pyridinium Group-containing compounds (for example, JP-A-4-365049) and diazonium group-containing compounds (for example, JP-A-5-2496).
No. 64, JP-A-6-83047, JP-A-6-3244
No. 95, JP-A-7-72621, etc.) can also be used in the present invention. Further, a compound capable of generating an acid by photolysis (JP-A-4-121748, JP-A-4-3650)
No. 43), a C—O—C group or a C— group dissociated by an acid.
A combination system with a compound having an O-Si group can also be used in the present invention. For example, a combination of a compound which generates an acid by photolysis and an acetal or an O, N-acetal compound (Japanese Patent Application Laid-Open No. 48-89003), a combination with an orthoester or amide acetal compound (Japanese Patent Application Laid-Open No. Sho 51-120714) ), In combination with a polymer having an acetal or ketal group in the main chain
-133429, etc.), and a combination with an enol ether compound (JP-A-55-12995, JP-A-4-19).
748, JP-A-6-230574, etc.) and a combination with an N-acylimino carbon compound (JP-A-55-126).
236), a combination with a polymer having an orthoester group in the main chain (JP-A-56-17345, etc.),
Combination with a polymer having a silyl ester group (for example, JP-A-60-10247) and combination with a silyl ether compound (JP-A-60-37549, JP-A-60-37549)
No. 0-112446, JP-A-63-236028, JP-A-63-236029, JP-A-63-276046
No.). The amount of these positive-acting photosensitive compounds (including the above combination) occupying in the photosensitive composition of the present invention is suitably from 10 to 50% by weight, more preferably from 15 to 40% by weight. It is.

Although the o-quinonediazide compound alone can constitute the photosensitive layer, it is preferably used together with a resin soluble in alkaline water as a binder. Such resins soluble in alkaline water include novolak resins having this property, such as phenol formaldehyde resin, m-cresol formaldehyde resin, p-cresol formaldehyde resin, and m- / p.
-Mixed cresol formaldehyde resin, phenol /
Cresol formaldehyde resin such as cresol (which may be any of m-, p-, o- or m- / p- / o-mixture) and the like. These alkaline soluble high molecular compounds preferably have a weight average molecular weight of 500 to 100,000. In addition, resol type phenol resins are also preferably used,
Phenol / cresol (m-, p-, o- or m- /
A mixed formaldehyde resin is preferable, and phenol resins described in JP-A-61-217034 are particularly preferable.

Also, a phenol-modified xylene resin, polyhydroxystyrene, polyhalogenated hydroxystyrene, an acrylic resin containing a phenolic hydroxyl group as disclosed in JP-A-51-34711, and JP-A-2-866. JP-A-7-28244, a vinyl resin or urethane resin having a sulfonamide group described in
JP-A-7-36184, JP-A-7-36185
JP-A-7-248628, JP-A-7-26139
No. 4, JP-A-7-333839, etc., various alkali-soluble polymer compounds such as a vinyl resin having a structural unit can be contained. In particular, in the case of a vinyl resin, a film-forming resin having as a polymerization component at least one selected from the following alkali-soluble group-containing monomers (1) to (14) is preferable.

(1) N- (4-hydroxyphenyl) acrylamide or N- (4-hydroxyphenyl) methacrylamide, o-, m- or p-hydroxystyrene, o- or m-bromo-p-hydroxystyrene, o- or m-chloro-p-hydroxystyrene,
acrylamides, methacrylamides, acrylates, methacrylates, and vidroxystyrenes having an aromatic hydroxyl group such as o-, m- or p-hydroxyphenyl acrylate or methacrylate; (2) acrylic acid, methacrylic acid Unsaturated maleic acid such as maleic acid, maleic anhydride and its half ester, itaconic acid, itaconic anhydride and its half ester,

(3) N- (o-aminosulfonylphenyl) acrylamide, N- (m-aminosulfonylphenyl) acrylamide, N- (p-aminosulfonylphenyl) acrylamide, N- [1- (3-aminosulfonyl) Naphthyl] acrylamide, acrylamides such as N- (2-aminosulfonylethyl) acrylamide, N- (o-aminosulfonylphenyl) methacrylamide, N- (m-aminosulfonylphenyl) methacrylamide, N- (p-aminosulfonyl) Phenyl)
Methacrylamides such as methacrylamide, N- [1- (3-aminosulfonyl) naphthyl] methacrylamide, N- (2-aminosulfonylethyl) methacrylamide, and o-aminosulfonylphenyl acrylate and m-aminosulfonylphenyl Acrylate, p
-Aminosulfonylphenyl acrylate, 1- (3-
Unsaturated sulfonamides such as acrylates such as aminosulfonylphenylnaphthyl) acrylate;
unsaturated sulfonamides such as methacrylic esters such as o-aminosulfonylphenyl methacrylate, m-aminosulfonylphenyl methacrylate, p-aminosulfonylphenyl methacrylate, 1- (3-aminosulfonylphenylnaphthyl) methacrylate;

(4) phenylsulfonylacrylamide which may have a substituent such as tosylacrylamide;
And phenylsulfonyl methacrylamide which may have a substituent such as tosyl methacrylamide. Furthermore, in addition to these alkali-soluble group-containing monomers, a film-forming resin obtained by copolymerizing the following monomers (5) to (14) is preferably used. (5) Acrylic esters and methacrylic esters having an aliphatic hydroxyl group, for example, 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate, (6) methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate , Amyl acrylate, hexyl acrylate, cyclohexyl acrylate, octyl acrylate, phenyl acrylate, benzyl acrylate, 2-chloroethyl acrylate, 4-hydroxybutyl acrylate, glycidyl acrylate, N-dimethylaminoethyl acrylate, etc. (Substituted) acrylate, (7) methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, silicone methacrylate Hexyl, octyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-chloroethyl, 4-hydroxybutyl methacrylate, glycidyl methacrylate, N- dimethyl (substituted) methacrylic acid esters such as aminoethyl methacrylate,

(8) Acrylamide, methacrylamide, N-methylol acrylamide, N-methylol methacrylamide, N-ethyl acrylamide, N-ethyl methacrylamide, N-hexyl acrylamide, N
-Hexyl methacrylamide, N-cyclohexyl acrylamide, N-cyclohexyl methacrylamide, N
-Hydroxyethylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, N
Acrylamides such as -phenylmethacrylamide, N-benzylacrylamide, N-benzylmethacrylamide, N-nitrophenylacrylamide, N-nitrophenylmethacrylamide, N-ethyl-N-phenylacrylamide and N-ethyl-N-phenylmethacrylamide Or methacrylamide, (9) vinyl ethers such as ethyl vinyl ether, 2-chloroethyl vinyl ether, hydroxyethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, octyl vinyl ether, and phenyl vinyl ether;

(10) vinyl esters such as vinyl acetate, vinyl chloroacetate, vinyl butyrate and vinyl benzoate; (11) styrenes such as styrene, α-methyl styrene, methyl styrene and chloromethyl styrene; Vinyl ketones such as methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, and phenyl vinyl ketone; (13) olefins such as ethylene, propylene, isobutylene, butadiene, and isoprene; (14) N-vinyl pyrrolidone, N-vinyl carbazole; 4-vinylpyridine, acrylonitrile, methacrylonitrile and the like.

These alkali-soluble polymer compounds are
Those having a weight average molecular weight of 500 to 500,000 are preferred. Such an alkali-soluble polymer compound may be used alone or in combination of two or more, and is 80% by weight or less of the total composition, preferably 30 to 80% by weight,
More preferably, it is used in an amount of 50 to 70% by weight. This range is preferable from the viewpoints of developability and printing durability.

Further, as described in US Pat. No. 4,123,279, an alkyl group having 3 to 8 carbon atoms as a substituent, such as a t-butylphenol formaldehyde resin and an octylphenol formaldehyde resin. It is preferable to use a condensate with phenol formaldehyde or an o-naphthoquinonediazidosulfonic acid ester of these condensates (for example, those described in JP-A-61-243446) in order to improve the oil sensitivity of an image.

(Development Accelerator) In the photosensitive composition of the present invention, it is preferable to add cyclic acid anhydrides, phenols and organic acids in order to increase sensitivity and improve developability. As cyclic acid anhydrides, US Pat.
Phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride described in US Pat. No. 5,128;
3,6-Endoxy-Δ ⁴ -tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, maleic anhydride, chloromaleic anhydride, α-phenylmaleic anhydride, succinic anhydride, pyromellitic anhydride and the like can be used. Examples of phenols include bisphenol A, p-nitrophenol, p-ethoxyphenol, 2,4,4'-trihydroxybenzophenone, 2,3,4-trihydroxybenzophenone, 4-hydroxybenzophenone,
4,4 ', 4 "-trihydroxy-triphenylmethane, 4,4', 3", 4 "-tetrahydroxy-3,
5,3 ', 5'-tetramethyltriphenylmethane and the like can be mentioned.

Further, as the organic acids, JP-A-60-8
No. 8942, JP-A-2-96755 and the like, there are sulfonic acids, sulfinic acids, alkyl sulfates, phosphonic acids, phosphoric esters and carboxylic acids, and specifically, p-toluene sulfone Acid, dodecylbenzenesulfonic acid, p-toluenesulfinic acid, ethyl sulfate, phenylphosphonic acid, phenylphosphinic acid, phenyl phosphate, diphenyl phosphate, benzoic acid, isophthalic acid, adipic acid, p-toluic acid,
3,4-dimethoxybenzoic acid, phthalic acid, terephthalic acid, 1,4-cyclohexene-2,2-dicarboxylic acid,
Erucic acid, lauric acid, n-undecanoic acid, ascorbic acid and the like can be mentioned. The proportion of the above-mentioned cyclic acid anhydrides, phenols and organic acids in the photosensitive composition is preferably from 0.05 to 15% by weight, more preferably from 0.1 to 5% by weight.

(Development Stabilizer) In the photosensitive composition of the present invention, JP-A-62-2517 is used in order to widen the stability of processing under development conditions (so-called development tolerance).
Non-ionic surfactants described in JP-A-59-1210 and JP-A No. 4-68355.
An amphoteric surfactant as described in JP-A-44-134 and JP-A-4-13149 can be added. Specific examples of the nonionic surfactant include sorbitan tristearate, sorbitan monopalmitate, sorbitan triolate, monoglyceride stearate, polyoxyethylene sorbitan monooleate, and polyoxyethylene nonyl phenyl ether. Specific examples of amphoteric surfactants include alkyldi (aminoethyl)
Glycine, alkyl polyaminoethyl glycine hydrochloride,
2-alkyl-N-carboxyethyl-N-hydroxyethylimidazolinium betaine and N-tetradecyl-
N, N-betaine type (for example, trade name Amogen K, manufactured by Daiichi Kogyo Co., Ltd.) and alkylimidazoline type (for example, trade name Levon 15, manufactured by Sanyo Chemical Co., Ltd.) and the like. The proportion of the nonionic surfactant and amphoteric surfactant in the photosensitive composition is preferably from 0.05 to 15% by weight, and more preferably from 0.1 to 5% by weight.

(Print-out Agent, Dye, Others) In the photosensitive composition of the present invention, a print-out agent for obtaining a visible image immediately after exposure, and a dye or other filler as an image coloring agent are added. be able to. As the dye that can be used in the present invention, a cation having a basic dye skeleton described in JP-A-5-313359 and a sulfonic acid group having only one exchange group and having 1 to 3 hydroxyl groups A basic dye comprising a salt with an organic anion having 10 or more carbon atoms can be used. The addition amount is 0.2 to 5% by weight of the total photosensitive composition.

Further, compounds capable of interacting with the dyes described in JP-A-5-313359 to generate photodegradable products that change color tone, such as those described in JP-A-50-36209 (US Pat. No. 3,969,118) O) -naphthoquinonediazide-4-sulfonic acid halogenide described in
No. 3-36223 (U.S. Pat. No. 4,160,671) discloses trihalomethyl-2-pyrone and trihalomethyltricidin, and JP-A-55-62444 (U.S. Pat.
38,801), various o-naphthoquinonediazide compounds described in JP-A-55-77742 (U.S. Pat.
279, 982).
An aryl 1,3,4-oxadiazole compound or the like can be added. These compounds can be used alone or as a mixture. 400n of these compounds
A compound having an absorption at m may be used as the yellow dye.

As a colorant for an image, the above-mentioned Japanese Patent Application Laid-Open No.
Other dyes besides the dyes described in JP 13359 can be used. Suitable dyes including salt-forming organic dyes include oil-soluble dyes and basic dyes.
Specifically, Oil Green BG, Oil Blue BO
S, Oil Blue # 603 (or more, manufactured by Orient Chemical Co., Ltd.), Victoria Pure Blue BOH, Victoria Pure Blue NAPS, Ethyl Violet 6H
NAPS (above, manufactured by Hodogaya Chemical Industry Co., Ltd.), Rhodamine B (C145170B), Malachite Green (C1
42000), methylene blue (C152015) and the like.

Further, in the photosensitive composition of the present invention,
The following yellow dyes can be added. Represented by the general formula [I], [II] or [III],
yellow dye whose absorbance at m is 70% or more of the absorbance at 436 nm

[0062]

Embedded image

In the formula [I], R₁And R_TwoAre independently
A hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group or
Represents an alkenyl group. Also R₁And R_TwoForms a ring
Good. R_Three, R_Four, R_FiveAre each independently a hydrogen atom or carbon
Shows the alkyl groups of Formulas 1 to 10. G₁, G_TwoIs German
Alkoxycarbonyl group, aryloxy carbonyl
Group, acyl group, arylcarbonyl group, alkylthio
Group, arylthio group, alkylsulfonyl group, aryl
Represents a sulfonyl group or a fluoroalkylsulfonyl group
You. G₁And G_TwoMay form a ring. Further R₁,
R_Two, R_Three, R_Four, R _Five, G₁, G_TwoOne or more of one or more
Upper sulfonic acid group, carboxyl group, sulfonamide
Group, imido group, N-sulfonylamido group, phenolic
Hydroxyl group, sulfonimide group, or a metal salt thereof, inorganic or
Has an organic ammonium salt. Y is O, S, NR (R is
A hydrogen atom or an alkyl or aryl group), Se,
-C (CH_Three)_Two-, A divalent element selected from -CH = CH-
Indicates a gang, n₁Represents 0 or 1.

[0064]

Embedded image

In the formula [II], R ₆ and R ₇ are each independently a hydrogen atom, an alkyl group, a substituted alkyl group, an aryl group,
Represents a substituted aryl group, a heterocyclic group, a substituted heterocyclic group, an allyl group or a substituted allyl group, and both R ₆ and R ₇ may form a ring together with the carbon atom to which it is bonded. n ₂ represents 0, 1 or 2. G ₃ and G ₄ are each independently a hydrogen atom, a cyano group, an alkoxycarbonyl group, a substituted alkoxycarbonyl group, an aryloxycarbonyl group, a substituted aryloxycarbonyl group, an acyl group, a substituted acyl group, an arylcarbonyl group, a substituted arylcarbonyl Group, alkylthio group, arylthio group, alkylsulfonyl group, arylsulfonyl group, and fluoroalkylsulfonyl group. However, G ₃ and G ₄ are not simultaneously hydrogen atoms. G ₃ and G ₄ may form a ring composed of a non-metallic atom together with the carbon atom to which they are bonded. Further, one of R ₆ , R ₇ , G ₃ and G ₄
One or more sulfonic acid groups, carboxyl groups, sulfonamide groups, imide groups, N-sulfonylamido groups,
It has a phenolic hydroxyl group, a sulfonimide group, or a metal salt thereof, or an inorganic or organic ammonium salt.

[0066]

Embedded image

In the formula [III], R ₈ , R ₉ , R ₁₀ , R ₁₁ , R
₁₂ and R ₁₃ may be the same or different, and each may be a hydrogen atom, an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, an alkoxy group, a hydroxyl group, an acyl group,
Represents a cyano group, an alkoxycarbonyl group, an aryloxycarbonyl group, a nitro group, a carboxyl group, a chloro group, or a bromo group.

The photosensitive lithographic printing plate of the present invention can be obtained by dissolving the above-mentioned components of the photosensitive composition in a solvent capable of dissolving and coating the solution on a support. As the solvent used here, γ-butyrolactone, ethylene dichloride, cyclohexanone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate,
1-methoxy-2-propanol, 1-methoxy-2-
Propyl acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, dimethyl sulfoxide, dimethylacetamide, dimethylformamide, water, N-methylpyrrolidone, tetrahydrofurfuryl alcohol, acetone, diacetone alcohol, methanol, ethanol,
There are isopropanol, diethylene glycol dimethyl ether and the like, and these solvents are used alone or in combination. The concentration (solid content) in the above components is 2 to
50% by weight is suitable. 0.5 g / m as coating amount
^{2 to} 4.0 g / m ² is preferred. When the amount is less than 0.5 g / m ² , the printing durability deteriorates. When the amount is more than 4.0 g / m ² , the printing durability is improved, but the sensitivity is lowered.

In the photosensitive composition of the present invention, a surfactant for improving the coating method, for example, JP-A-62-2
A fluorine-based surfactant as described in JP-A-170950 can be added. The preferred amount is
It is 0.01 to 1% by weight of the total photosensitive composition, and more preferably 0.05 to 0.5% by weight. With the lithographic printing plate obtained as described above, a printed matter faithful to the original picture film can be obtained, but the print blurring and the roughness of the printed matter are poor. As a method of improving the burning blur, there is a method of making the surface of the photosensitive amount provided in this way uneven. For example, as described in Japanese Patent Application Laid-Open No. 61-258255, there is a method in which particles of several μm are added to a photosensitive solution, and the particles are coated. Is not improved at all.

However, for example, Japanese Patent Application Laid-Open No. Sho 50-12580
No. 5, JP-B-57-6582, JP-B-61-28986
And Japanese Patent Application Laid-Open No. 62-62337, the method of forming a component having irregularities on the surface of the photosensitive amount can improve bokeh blur and improve the roughness of the printed matter. Furthermore, as described in JP-B-55-30619, when a light absorbing agent having absorption in the photosensitive wavelength region of the photosensitive material is contained in the mat layer, the burning blur and the roughness are further improved. In addition, an original film having a line number of 300 lines or more per inch and an original film obtained by FM screening, which is more easily burned out than an original film having a line number of 175 lines per inch and which easily gives a sense of roughness of a printed material, is used. Thus, a good printed matter can be obtained. As described above, the following fine patterns are preferably provided on the surface of the photosensitive layer of the photosensitive printing plate. That is, the height of the coated portion is preferably in the range of 1 to 40 μm, particularly 2 to 20 μm, and the size (width) is 10 to 10000 μm, especially 20
The range of -200 µm is preferred. The amount is 1 to 1000
Pieces / mm ² , preferably in the range of 5 to 500 pieces / mm ² .

<3> Development Processing Next, the development processing of the photosensitive lithographic printing plate of the present invention will be described. (Exposure) The photosensitive lithographic printing plate of the present invention is developed after being subjected to image exposure. The light source of the active light beam used for the image exposure includes a carbon arc lamp, a mercury lamp, a metal halide lamp, a xenon lamp, a tungsten lamp, a chemical lamp and the like. Examples of the radiation include an electron beam, an X-ray, an ion beam, and a far-infrared ray. Also, g-line, i-line, D
Eep-UV light and high-density energy beam (laser beam) are also used. Examples of the laser beam include a helium-neon laser, an argon laser, a krypton laser, a helium-cadmium laser, a KrF excimer laser, a semiconductor laser, and a YAG laser.

(Developer) A preferable developer for the photosensitive lithographic printing plate of the present invention is an alkaline aqueous solution containing substantially no organic solvent. Specifically, sodium silicate, potassium silicate, NaOH, KOH, LiOH,
Aqueous solutions such as sodium phosphate, dibasic sodium phosphate, tribasic ammonium phosphate, dibasic ammonium phosphate, sodium metasilicate, sodium carbonate, sodium bicarbonate, potassium carbonate, aqueous ammonia and the like are suitable.
More preferably, the developer contains (a) at least one saccharide selected from non-reducing sugars and (b) at least one base, and has a pH in the range of 9.0 to 13.5. Hereinafter, the developer will be described in detail. In the present specification, unless otherwise specified, the developing solution means a developing solution (a developing solution in a narrow sense) and a developing replenisher.

(Non-Reducing Sugar and Base) The developer has at least one compound selected from non-reducing sugars and at least one base, and the pH of the solution is 9.
It is characterized by being in the range of 0 to 13.5. Such non-reducing sugars have no free aldehyde or ketone groups,
It is a saccharide that does not show reducing properties, and is classified as a trehalose-type oligosaccharide in which reducing groups are bonded to each other, a glycoside in which a reducing group of a saccharide is bonded to a non-saccharide, and a sugar alcohol which is hydrogenated and reduced to a saccharide. It is preferably used. Trehalose-type oligosaccharides include saccharose and trehalose, and examples of glycosides include alkyl glycosides, phenol glycosides, and mustard oil glycosides. Examples of sugar alcohols include D, L-arabit, ribit, xylit, D, L
-Sorbit, D, L-mannit, D, L-idit, D, L-tallit, zuricit and allozurcit. Further, maltitol obtained by hydrogenation of disaccharide and reductant (reduced starch syrup) obtained by hydrogenation of oligosaccharide are preferably used. Among these, non-reducing sugars which are particularly preferred are sugar alcohols and saccharose, and D-sorbitol, saccharose and reduced starch syrup are particularly preferred because they have a buffering action in an appropriate pH range and are inexpensive. These non-reducing sugars can be used alone or in combination of two or more kinds, and their ratio in the developer is preferably from 0.1 to 30% by weight, more preferably from 1 to 20% by weight. Below this range, a sufficient buffering effect cannot be obtained, and at concentrations above this range, it is difficult to achieve high concentration, and there is a problem of cost increase. still,
When a reducing sugar is used in combination with a base, there is a problem in that the color changes to brown with time, the pH gradually decreases, and the developability decreases.

As a base to be combined with the non-reducing sugar, a conventionally known alkali agent can be used. For example, sodium hydroxide, potassium, lithium, trisodium phosphate, potassium, ammonium, disodium phosphate, potassium, ammonium, sodium carbonate, potassium, ammonium, sodium hydrogencarbonate, potassium, ammonium And inorganic alkali agents such as sodium borate, potassium and ammonium. Also, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropynolamine, diisopropanolamine And organic alkali agents such as ethyleneimine, ethylenediamine and pyridine. These alkali agents are used alone or in combination of two or more. Among these, sodium hydroxide and potassium hydroxide are preferred. The reason is that by adjusting these amounts to non-reducing sugars, pH
This is because adjustment becomes possible. Further, trisodium phosphate, potassium phosphate, sodium carbonate, potassium phosphate and the like are also preferable since they themselves have a buffering action. These alkaline agents are added so that the pH of the developing solution is in the range of 9.0 to 13.5, and the amount of addition is determined depending on the desired pH, the type and the amount of non-reducing sugar, but more preferable pH The range is from 10.0 to 13.2.

Further, an alkaline buffer consisting of a weak acid other than saccharides and a strong base can be used in combination with the developer. As a weak acid used as such a buffer, pKa is 10.0 to 1
3.2 are preferred. Such weak acids include Pe
IONISATION CONSTANTS OF ORGANI published by rgamon Press
Selected from those described in C ACIDS IN AQUEOUS SOLUTION and the like, for example, 2,2,3,3-tetrafluoropropanol-1 (pKa 12.74), trifluoroethanol (12.37), trichloroethanol (12 Alcohols such as 12.24), pyridine-2-
Aldehydes such as aldehyde (12.68) and pyridine-4-aldehyde (12.05), salicylic acid (13.0), 3-hydroxy-2-naphthoic acid (12.84) and catechol (12.84) 12.6), gallic acid (12.4), sulfosalicylic acid (11.7),
3,4-dihydroxysulfonic acid (12.2 above), 3,
4-dihydroxybenzoic acid (11.94), 1,2,2
4-trihydroxybenzene (11.82), hydroquinone (11.56), pyrogallol (11.3)
4), o-cresol (10.33), resorcinol (11.27), p-cresol (10.2)
7) compounds having a phenolic hydroxyl group, such as m-cresol (10.09);

2-butanone oxime (12.45);
Acetoxime (12.42), 1,2-cycloheptanedione dioxime (12.3), 2-hydroxybenzaldehyde oxime (12.10), dimethylglyoxime (11.9), ethanediamide dioxime (11.37) and acetophenone oxime (11.37).
Oximes such as 35) and adenosine (12.5
6), inosine (12.5) and guanine (12.
3), cytosine (12.2), hypoxanthine (1)
2.1), nucleic acid-related substances such as xanthine (11.9), and diethylaminomethylphosphonic acid (12.
32), 1-amino-3,3,3-trifluorobenzoic acid (12.29), isopropylidene diphosphonic acid (12.10), 1,1-ethylidene diphosphonic acid (11.54) , 1,1-ethylidene diphosphonic acid 1
-Hydroxy (11.52), benzimidazole (12.86), thiobenzamide (12.8),
Weak acids such as picoline thioamide (12.55) and barbituric acid (12.5).

Among these weak acids, preferred are sulfosalicylic acid and salicylic acid. As the base to be combined with these weak acids, sodium hydroxide, ammonium hydroxide, potassium hydroxide and lithium hydroxide are preferably used.
These alkali agents are used alone or in combination of two or more. The above-mentioned various alkaline agents are used by adjusting the pH within a preferred range depending on the concentration and combination.

(Surfactant) To the developer, various surfactants and organic solvents can be added as necessary for the purpose of accelerating the developing property, dispersing the developing residue and increasing the ink affinity of the printing plate image area. Preferred surfactants include anionic,
Cationic, nonionic and amphoteric surfactants are included. Preferred examples of the surfactant include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene polystyryl phenyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, glycerin fatty acid partial esters, and sorbitan. Fatty acid partial esters, pentaerythritol fatty acid partial esters, propylene glycol monofatty acid esters, sucrose fatty acid partial esters, polyoxyethylene sorbitan fatty acid partial esters, polyoxyethylene sorbitol fatty acid partial esters, polyethylene glycol fatty acid esters, poly Glycerin fatty acid partial esters, polyoxyethylenated castor oil, polyoxyethylene glycerin fatty acid partial esters, fatty acids Ethanol amides, N, N
Non-ionic surfactants such as -bis-2-hydroxyalkylamines, polyoxyethylene alkylamines, triethanolamine fatty acid esters, and trialkylamine oxides;

Fatty acid salts, abietic acid salts, hydroxyalkanesulfonic acid salts, alkanesulfonic acid salts,
Dialkyl sulfosuccinates, linear alkylbenzene sulfonates, branched alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkylphenoxy polyoxyethylene propyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, N-methyl- N-oleyltaurine sodium salt, N-alkylsulfosuccinic acid monoamide disodium salt, petroleum sulfonates, sulfated tallow oil, sulfates of fatty acid alkyl esters, alkyl sulfates, polyoxyethylene alkyl ether sulfates, Fatty acid monoglyceride sulfate salts, polyoxyethylene alkyl phenyl ether sulfate salts, polyoxyethylene styryl phenyl ether sulfate salts, Alkyl phosphate phosphate salts, polyoxyethylene alkyl ether phosphate salts, polyoxyethylene alkyl phenyl ether phosphate salts, partially saponified styrene / maleic anhydride copolymers, partial olefin / maleic anhydride copolymers Anionic surfactants such as saponified products and naphthalene sulfonate formalin condensates; quaternary ammonium salts such as alkylamine salts and tetrabutylammonium bromide; cationic interfaces such as polyoxyethylene alkylamine salts and polyethylene polyamine derivatives. Activators, amphoteric surfactants such as carboxybetaines, aminocarboxylic acids, sulfobetaines, aminosulfates, and imidazolines. Among the surfactants mentioned above, the term "polyoxyethylene" can be read as a polyoxyalkylene such as polyoxymethylene, polyoxypropylene, or polyoxybutylene, and these surfactants are also included.

Further preferred surfactants are fluorine-based surfactants containing a perfluoroalkyl group in the molecule. Such fluorosurfactants include perfluoroalkyl carboxylate, perfluoroalkyl sulfonate, anionic type such as perfluoroalkyl phosphate, amphoteric type such as perfluoroalkyl betaine,
Cationic and perfluoroalkylamine oxides such as perfluoroalkyltrimethylammonium salts, perfluoroalkylethylene oxide adducts, oligomers containing perfluoroalkyl groups and hydrophilic groups,
Non-ionic types such as oligomers containing perfluoroalkyl groups and lipophilic groups, oligomers containing perfluoroalkyl groups, hydrophilic groups and lipophilic groups, and urethanes containing perfluoroalkyl groups and lipophilic groups are included. The above surfactants can be used alone or in combination of two or more, and are added to the developer in an amount of 0.001 to 10% by weight, more preferably 0.01 to 5% by weight.

(Development Stabilizer) Various development stabilizers are used in the developer. Preferred examples thereof include polyethylene glycol adducts of sugar alcohols described in JP-A-6-282079, tetraalkylammonium salts such as tetrabutylammonium hydroxide, phosphonium salts such as tetrabutylphosphonium bromide, and iodonium such as diphenyliodonium chloride. Salts are mentioned as preferred examples. Further, anionic surfactants or amphoteric surfactants described in JP-A-50-51324, water-soluble cationic polymers described in JP-A-55-95946,
There is a water-soluble amphoteric polymer electrolyte described in 142,528. Further, an organic boron compound to which an alkylene glycol has been added described in JP-A-59-84241, a polyoxyethylene / polyoxypropylene block polymerization type water-soluble surfactant described in JP-A-60-111246, Polyoxyethylene / polyoxypropylene-substituted alkylenediamine compounds described in JP-A-60-129750, polyethylene glycol having a weight average molecular weight of 300 or more described in JP-A-61-215554, and cations described in JP-A-63-175858 Fluorinated surfactant having a functional group, JP-A-2-39157
And a water-soluble polyalkylene compound obtained by adding 4 moles or more of ethylene oxide to the acid or alcohol described in the publication.

(Organic Solvent) The developer of the present invention does not substantially contain an organic solvent, but an organic solvent is added if necessary. As such an organic solvent, those having a solubility in water of about 10% by weight or less are suitable, and preferably selected from those having a solubility 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-methylcyclohexanol, 3-methylcyclohexanol and 4-methylcyclohexanol, N
-Phenylethanolamine and N-phenyldiethanolamine. "Substantially free of an organic solvent" in the developer of the present invention means that the content of the organic solvent is 5% by weight or less based on the total weight of the used solution. The amount used is closely related to the amount used of the surfactant, and it is preferable to increase the amount of the surfactant as the amount of the organic solvent increases. This is because when the amount of the surfactant is small and the amount of the organic solvent is large, the organic solvent is not completely dissolved, and therefore, it is impossible to expect good developing property.

(Reducing Agent) A reducing agent can be further added to the developer. This is to prevent the printing plate from being stained, and is particularly effective when developing a negative photosensitive lithographic printing plate containing a photosensitive diazonium salt compound. Preferred organic reducing agents include thiosalicylic acid, hydroquinone, methol, methoxyquinone, resorcinol, phenol compounds such as 2-methylresorcinol, phenylenediamine,
Examples include amine compounds such as phenylhydrazine.
More preferred inorganic reducing agents include sulfurous acid, bisulfite, phosphorous acid, hydrogen phosphite, dihydrophosphite,
Examples thereof include sodium salts, potassium salts, and ammonium salts of inorganic acids such as thiosulfuric acid and dithionous acid. Among these reducing agents, sulfites are particularly excellent in the stain prevention effect. These reducing agents are preferably contained in a range of 0.05 to 5% by weight with respect to the developing solution at the time of use.

(Organic carboxylic acid) An organic carboxylic acid can be further added to the developer. Preferred organic carboxylic acids are aliphatic and aromatic carboxylic acids having 6 to 20 carbon atoms. Specific examples of the aliphatic carboxylic acid include caproic acid, enantiic acid, caprylic acid, lauric acid, myristic acid, palmitic acid and stearic acid, and particularly preferred are alkanoic acids having 8 to 12 carbon atoms. . Further, unsaturated fatty acids having a double bond in the carbon chain or branched fatty acids may be used. The aromatic carboxylic acid is a compound in which a carboxyl group is substituted on a benzene ring, a naphthalene ring, an anthracene ring, or the like. Specifically, o-chlorobenzoic acid, p-chlorobenzoic acid, o-hydroxybenzoic acid, p- Hydroxybenzoic acid, o-aminobenzoic acid, p-aminobenzoic acid, 2,4
-Dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, gallic acid, 1-hydroxy-2-naphthoic acid, 3 -Hydroxy-2-naphthoic acid, 2-hydroxy-1-naphthoic acid,
There are 1-naphthoic acid and 2-naphthoic acid, and hydroxynaphthoic acid is particularly effective. The above aliphatic and aromatic carboxylic acids are preferably used as a sodium salt, a potassium salt or an ammonium salt in order to enhance water solubility. The content of the organic carboxylic acid in the developer used in the present invention is not particularly limited, but if the content is less than 0.1% by weight, the effect is not sufficient, and if it is 10% by weight or more, the effect cannot be further improved. In addition, dissolution may be hindered when another additive is used in combination. Therefore, the preferred addition amount is 0.1 to 10% by weight, more preferably 0.5 to 4% by weight, based on the developer used.

(Others) The developer may further contain a preservative, a coloring agent, a thickener, an antifoaming agent, a water softener and the like, if necessary. Examples of the water softener include polyphosphoric acid and its sodium salt, potassium salt and ammonium salt, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, triethylenetetraminehexaacetic acid, hydroxyethylethylenediaminetriacetic acid, nitrilotriacetic acid, 1,2-diaminocyclohexanetetraacetic acid. Aminopolycarboxylic acids such as acetic acid and 1,3-diamino-2-propanoltetraacetic acid and their sodium, potassium and ammonium salts;
Aminotri (methylenephosphonic acid), ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphonic acid), triethylenetetraminehexa (methylenephosphonic acid), hydroxyethylethylenediaminetri (methylenephosphonic acid) and 1-
Examples include hydroxyethane-1,1-diphosphonic acid and their sodium, potassium and ammonium salts.

The optimum value of such a water softener varies depending on the chelating power, the hardness of the hard water used and the amount of hard water. 01 to 5% by weight, more preferably 0.01 to 5% by weight
It is in the range of 0.5% by weight. If the added amount is less than this range, the intended purpose is not sufficiently achieved, and if the added amount is larger than this range, an adverse effect on an image portion such as color omission appears. The remaining component of the developer is water. It is advantageous from the viewpoint of transportation that the developing solution is a concentrated solution in which the content of water is smaller than that at the time of use, and is diluted with water at the time of use. In this case, the concentration is suitably such that the components do not separate or precipitate.

As the developer for the photosensitive lithographic printing plate of the present invention, the developer described in JP-A-6-282079 can also be used. This is because an alkali metal silicate having a molar ratio of SiO ₂ / M ₂ O (M represents an alkali metal) of 0.5 to 2.0, and a sugar alcohol having 4 or more hydroxyl groups are added with 5 mol or more of ethylene oxide. Developer containing a water-soluble ethylene oxide addition compound obtained by the above method. Sugar alcohol is a polyhydric alcohol corresponding to one obtained by reducing an aldehyde group and a ketone group of a sugar to form primary and secondary alcohol groups, respectively. Specific examples of sugar alcohols include D, L-trait, erythritol, D, L-arabit, ribit, xylit, D, L-sorbit,
D, L-mannit, D, L-idit, D, L-talit, dursit, allozursit and the like, and further di-, tri-, tetra-, penta- and hexaglycerin condensed with a sugar alcohol. The water-soluble ethylene oxide adduct is obtained by adding 5 mol or more of ethylene oxide to 1 mol of the sugar alcohol. Further, propylene oxide may be block-copolymerized with the ethylene oxide-added compound, if necessary, as long as the solubility is acceptable. These ethylene oxide addition compounds may be used alone or in combination of two or more. The addition amount of these water-soluble ethylene oxide addition compounds is from 0.001 to 5
% Is suitable, more preferably 0.001-2% by weight. The above-mentioned various surfactants and organic solvents can be further added to this developer, if necessary, for the purpose of promoting the developability, dispersing the development residue, and enhancing the ink affinity of the printing plate image area.

(Development and Post-processing) A PS plate developed with a developer having such a composition may be washed with water, a rinsing solution containing a surfactant or the like, a finisher or a protective gum mainly containing gum arabic or a starch derivative. The liquid is post-treated.
These treatments can be used in various combinations for the post-treatment of the PS plate of the present invention. In recent years, in the plate making and printing industries, automatic developing machines for PS plates have been widely used in order to streamline and standardize plate making operations. This automatic developing machine generally comprises a developing section and a post-processing section, and comprises a device for transporting a PS plate, each processing solution tank and a spray device, and pumps the exposed PS plate horizontally while pumping it. Each processing liquid is sprayed from a spray nozzle to perform development and post-processing. Recently, a PS plate is immersed and transported by a submerged guide roll or the like in a processing solution tank filled with a processing solution to carry out development processing, or a fixed amount of small amount of washing water is supplied to the plate surface after development for washing. There is also known a method of reusing the waste water as dilution water of a developer undiluted solution. In such automatic processing, processing can be performed while replenishing each processing solution with a replenisher in accordance with the processing amount, operating time, and the like. Further, a so-called disposable processing method in which processing is performed with a substantially unused processing liquid can also be applied. The lithographic printing plate obtained by such a process is set on an offset printing machine and used for printing a large number of sheets.

[0089]

EXAMPLES Next, examples of the present invention will be shown and described in detail. Of course, the scope of the present invention is not limited by these. All percentages in the following examples are% by weight unless otherwise specified. (Examples 1 to 4, Comparative Examples 1 to 5) JI having a thickness of 0.24 mm
The surface of the SA1050 aluminum plate was grained using a nylon brush and an aqueous suspension of pumicestone of 400 mesh, and then thoroughly washed with water. After immersing in a 10% aqueous sodium hydroxide solution at 70 ° C. for 60 seconds for etching,
After washing with running water, neutralization washing with 20% HNO ₃ and washing with water were performed.
This was subjected to electrolytic surface roughening treatment in a 1% nitric acid aqueous solution at an anode-time electricity quantity of 260 coulomb / dm ² using a sinusoidal alternating waveform current under the condition of V _A = 12.7 V. When the surface roughness was measured, it was 0.55 μm (Ra indication).
Subsequently, it was immersed in a 30% aqueous solution of H ₂ SO ₄ ,
After desmutting at 20 ° C. for 2 minutes, the current density in a 20% H ₂ SO ₄ aqueous solution was 14 A / dm ² , and the anodic oxide film amount was 2.5 g / m 2.
^The substrate was anodized so as to be equivalent to ² and washed with water to prepare a substrate [A]. The substrate [A] was treated with a 2.5% by weight aqueous solution of sodium silicate at 30 ° C. for 10 seconds, and washed with water to form a substrate [B]. A coating solution having the following composition was applied to the surface of the substrate [A] or [B] treated as described above with the polymer compound of the present invention shown in Table 1 and dried at 80 ° C. for 15 seconds.
The coating amount after drying was 15 mg / m ² .

Next, a photosensitive layer is provided by applying the following photosensitive solution [A] on this substrate. The photosensitive layer coating amount after drying is 1.2 g
/ M ² . Further, in order to shorten the vacuum adhesion time, a photosensitive lithographic printing plate was prepared by forming a mat layer by the method described in JP-B-61-28986 (Examples 1 to 4).

For comparison, a substrate having no intermediate layer was prepared on the substrate [A] (Comparative Examples 1 and 2). Further, for comparison, a substrate having no intermediate layer on the surface of the substrate [B] was prepared (Comparative Example 3). Apply, 80
It dried at 15 ° C for 15 seconds (Comparative Examples 4, 5). Next, a photosensitive lithographic printing plate was prepared by providing a photosensitive layer and a mat layer on these substrates in the same manner as in Examples 1 to 4.

[Photosensitive solution A] Esterified product of 1,2-diazonaphthoquinone-5-sulfonyl chloride and pyrogallol-acetone resin (described in Example 1 of US Pat. No. 3,635,709) 8 g binder novolak I 1.5 g novolak II 0.2 g resin other than novolak III 0.4 g p-n-octylphenol-formaldehyde resin (as described in U.S. Pat. No. 4,123,279) 0.02 g naphthoquinone-1,2 -Diazido-4-sulfonic acid chloride 0.01 g tetrahydrophthalic anhydride 0.02 g benzoic acid 0.02 g pyrogallol 0.05 g 4- [p-N, N-bis (ethoxycarbonylmethyl) aminophenyl] -2,6- Bis (trichloromethyl) -S-triazine (hereinafter triazine A) 0.07 g Victoria Pure Blue BOH (a dye manufactured by Hodogaya Chemical Co., Ltd. in which the counter anion is changed to 1-naphthalenesulfonic acid) 0.045 g F176PF (fluorinated surfactant) (Dainippon Ink Chemical Industry Co., Ltd.) )) 0.01 g methyl ethyl ketone 15 g 1-methoxy-2-propanol 10 g

[0093]

Embedded image

The photosensitive lithographic printing plate thus prepared was
m with a 3 kW metal halide lamp for 1 minute from a distance of 30 m using a PS processor 900VR manufactured by Fuji Photo Film Co., Ltd. using the following developer.
Development was performed at 12 ° C. for 12 seconds. Developer A: D-sorbitol 5.1 parts by weight Sodium hydroxide 1.1 parts by weight Triethanolamine / ethylene oxide adduct (30 mol) 0.03 parts by weight Water 93.8 parts by weight Developer B: [SiO ₂ ] / [Na ₂ O] molar ratio 1.2 SiO ₂ 1.4% by weight of sodium silicate aqueous solution 100 parts by weight Ethylenediamine / ethylene oxide adduct (30 mol) 0.03 parts by weight

After the development processing as described above, the difference between the density of the non-image area and the density of the substrate before coating was visually evaluated for the remaining color of the non-image area as follows. ◎: No color difference between non-image area and substrate before coating ○: Almost no color difference between non-image area and substrate before coating △: Slightly smaller in non-image area than before coating It looks dark ×: The non-image part looks clearly darker than the substrate before coating 2 ×: The non-image part looks extremely darker than the substrate before coating , 2000
After printing the sheet, the printing plate was removed from the printing press, left to stand for 60 minutes, and printing was restarted again. At this time, how the ink in the non-image area was removed was evaluated as follows. …: Non-image area ink is quickly dispensed. △: Non-image area ink is dispensed somewhat slow. ×: Non-image area ink is dispensed very slowly. 2 ×: Non-image area. Ink is dispensed very slowly

For the whitening of the non-image area, the difference between the whiteness of the non-image area and the whiteness of the substrate before coating was visually evaluated as follows. ◎: There is no difference in whiteness between the non-image area and before coating.…: There is almost no difference in whiteness between the non-image area and before coating. ×: The non-image area looks whiter than the substrate before coating. The printing durability was evaluated by using a printing machine Sprint manufactured by Komori Printing Machine Co., Ltd. to determine how many sheets could be printed. The greater the number of printed sheets, the better the printing durability.

Table 1 shows the results. From the results, it can be seen that the photosensitive lithographic printing plate of the present invention is excellent in all of residual color, standing stain, whitening and printing durability.

[0098]

[Table 1]

(Examples 5 to 10 and Comparative Examples 6 to 10) The surface of a JIS A1050 aluminum plate having a thickness of 0.24 mm was grained using a nylon brush and an aqueous suspension of pumicestone of 400 mesh, and then thoroughly watered. And washed. 10%
After immersion in an aqueous solution of sodium hydroxide at 70 ° C. for 60 seconds for etching, washing with running water, neutralization washing with 20% HNO ₃ and washing with water. This was conducted in a 1% aqueous nitric acid solution using a sinusoidal alternating current under the condition of _VA = 12.7V.
Electrolytic surface-roughening treatment was performed with an amount of electricity at the anode of Coulomb / dm ² . The surface roughness was measured to be 0.55 μm (Ra
Display). Subsequently, it was immersed in a 30% aqueous solution of H ₂ SO _{4 and} desmutted at 55 ° C. for 2 minutes.
The substrate was anodized in a H ₂ SO ₄ aqueous solution such that the current density was 14 A / dm ² and the amount of the anodic oxide film was equivalent to 2.5 g / m ² . The substrate [C] was treated with a 2.5% by weight aqueous solution of sodium silicate at 30 ° C. for 10 seconds, and washed with water to prepare a substrate [D]. The polymer compound of the present invention shown in Table 3 was applied to the surface of the substrate [C] or [D] thus treated, and dried at 80 ° C. for 15 seconds. The coating amount after drying was 15 mg / m ² .

Next, a photosensitive layer is provided by applying the following photosensitive solution [B] on this substrate: 0.3 g of the polymer compound in Table 2 100 g of methanol 100 g of water The amount of the photosensitive layer coating after drying is 1.7 g.
/ M ² . Further, in order to shorten the vacuum adhesion time, a photosensitive lithographic printing plate was prepared by forming a mat layer by the method described in JP-B-61-28986 (Examples 5 to 10).

For comparison, a substrate having neither the treatment nor the intermediate layer applied to the substrate [C] was prepared (Comparative Examples 6 and 7). For comparison, a substrate having no intermediate layer on the surface of the substrate [D] was also prepared (Comparative Example 8). Further, a solution not corresponding to the polymer compound of the present invention is applied on the surface of the substrate [D],
It was dried at 80 ° C. for 15 seconds (Comparative Examples 9, 10). Next, a photosensitive layer and a mat layer were provided on these substrates in the same manner as in Examples 5 to 10 to prepare photosensitive lithographic printing plates.

[Photosensitive solution B] Esterified product of 1,2-diazonaphthoquinone-5-sulfonyl chloride and pyrogallol-acetone resin (described in Example 1 of US Pat. No. 3,635,709) 9 g binder novolak IV 1.60 g novolak V 0.3 g p-normal octylphenol-formaldehyde resin (described in U.S. Pat. No. 4,123,279) 0.02 g naphthoquinone-1,2-diazide-4-sulfonic acid chloride 0.01 g Tetrahydrophthalic anhydride 0.02 g Benzoic acid 0.02 g Pyrogallol 0.05 g Triazine A 0.07 g Victoria Pure Blue BOH (a dye manufactured by Hodogaya Chemical Co., Ltd. in which the counter anion is changed to 1-naphthalenesulfonic acid) 0.10g F176PF (Fluorine surfactant Agent) (manufactured by Dainippon Ink and Chemicals, Inc.) 0.06 g methyl ethyl ketone 12.0 g

[0103]

Embedded image

The photosensitive lithographic printing plate thus prepared was image-exposed in the same manner as in Example 1, and as shown in Table 2, using the above-mentioned developing solutions A and B, in the same manner as in Example 1. Developed.

After the development, the remaining color, standing stain, whitening and printing durability were evaluated in the same manner as in Example 1. Table 2 shows the results. From the results, it can be seen that the photosensitive lithographic printing plate of the present invention is excellent in all of residual color, standing stain, whitening and printing durability.

[0106]

[Table 2]

[0107]

As described above, according to the present invention, it is possible to provide a positive photosensitive lithographic printing plate having excellent residual color, standing stain, whitening and printing durability. Further, even when development is performed using a developer containing no silicate, a positive photosensitive lithographic printing plate having good stain and printing durability can be provided.

Claims (1)

[Claims] 1. An intermediate layer containing a polymer compound containing a repeating unit represented by the following general formula (1) is provided on an aluminum support subjected to a hydrophilic treatment, and a positive photosensitive layer is formed on the intermediate layer. A photosensitive lithographic printing plate provided. Embedded image (Wherein, A represents an aromatic group, a —COO— group, a —CONH— group or a —CON (CH ₃ ) — group, L represents a divalent linking group, R ₁ represents a hydrogen atom, a halogen atom, X represents an alkyl group, and X represents an acid group having a pKa of 7 or less, or an alkali metal salt or an ammonium salt thereof.)