JPH0369946A - Development processing method for photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To allow development with a stable finish by incorporating a specific compd. into the rear surface and/or over coating layer of a negative type PS plate. CONSTITUTION:Acid, sulfite or anionic surfactant are incorporated into the rear surface or over coating layer of the negative type PS plate in the development processing method for processing the negative type PS plate with a developer to be repetitively used after image exposing. A recommended practice in this case is to provide a layer contg. a polymer soluble in or swellable with an alkali as a binder on rear surface and/or photosensitive layer of the PS plate and to incorporate the compd. into the layer. The always stable developing performance is obtd. even if the processing is executed over a long period of time by using an automatic developing machine and the developer to be repetitively used while replenishing the soln. with a development replenishing soln.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for developing a photosensitive lithographic printing plate (hereinafter referred to as 113 plate). This invention relates to a method for developing a negative type 18 plate with a developer that can be replenished and used repeatedly.

[Background of the invention]

When 28 plates are processed continuously using an automatic developing machine that circulates the developer, the activity of the developer decreases. In order to prevent this decrease in activity, it is known to replenish the repeatedly used developer with a developer replenisher to maintain the developability at a constant level.

It is known that adding an acid, a sulfite, an anionic surfactant, etc. to a negative PS plate developer can maintain stable developability. However, since developer replenisher is usually a concentrated solution and is diluted with water before use, it is often difficult for acids, sulfites, anionic surfactants, etc. to dissolve in the concentrated solution of developer replenisher. There is a problem in which it is difficult to obtain stable development results due to a shortage of components, and when the negative 18th plate and the positive 13th plate are commonly developed with the same developer, there may be excess or deficiency in these components, making it difficult to obtain stable results. There is a problem that the finished product cannot be obtained.

[Problem that the invention seeks to solve]

The present invention aims to solve the above-mentioned technical problem, and an object of the present invention is to replenish the developer replenisher using an automatic processor and process the same problem over a long period of time with a developer that is used repeatedly. It is an object of the present invention to provide a developing processing method for a negative type 15 plate that can always obtain stable developing performance.

Another object of the present invention is to develop a negative 15th plate and a positive PS plate with a common developer that can be reused repeatedly by replenishing a developer replenisher, and can be developed with a stable finish. An object of the present invention is to provide a method for developing a plate.

[Means for solving problems]

The object of the present invention is to provide a development processing method in which a negative 15th plate is processed with a repeatedly used developer after image exposure.
This is achieved by a method for developing a photosensitive lithographic printing plate in which at least one of the back surface or overcoat layer of a negative-working 15th plate contains an acid, a sulfite, or an anionic surfactant.

The present invention will be explained in detail below.

In the present invention, the above-mentioned compound (hereinafter referred to as "compound of the present invention") to be contained in the back surface and/or overcoat layer of the negative 15th plate is contained in the back surface or the overcoat layer of the negative 15th plate It is preferable to provide a layer containing an alkali-soluble or alkali-swellable polymer as a binder on the back surface of the PS plate and/or the photosensitive layer, and to contain the compound of the present invention in the layer. Further, when the compound of the present invention is a film-forming compound, the above-mentioned binder may not be used.

As an alkali-soluble or alkali-swellable polymer,
For example, polyvinyl alcohol, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylpyrrolidone, polysodium-L-glutamate, water-soluble polyvinyl butyral, copolymer of vinyl alcohol and maleic acid, copolymer of vinyl alcohol and acrylamide, vinyl Polymers such as a copolymer of pyrrolidone and vinyl acetate, and a copolymer of (meth)acrylic acid ester and (meth)acrylic acid are mentioned, and these can be used alone or in combination of two or more kinds.

In addition, the above binders include methylcellulose, carboxymethylcellulose, hydroxyethylcellulose,
Cellulose ethers such as hydroxypropyl methylcellulose; natural polymeric compounds such as casein, albumin, gelatin (including acylated gelatin), and gum arabic can also be used.

The amount of the binder in such back layer and overcoat layer is not particularly limited, but each is O01~5.0g7m2
A range of is appropriate.

Examples of acids in the compounds of the present invention include inorganic acids such as phosphoric acid, polyphosphoric acid, hydrochloric acid, sulfuric acid, nitric acid, acetic acid,
Oxalic acid, tartaric acid, benzoic acid, succinic acid, citric acid, malic acid, lactic acid, tannic acid, glycine, alanine, sarcosine, valine, leucinic acid, ascurpic acid, levulinic acid, p-toluic acid, p-toluenesulfonic acid , 2-pyridinecarboxylic acid, phthalic acid, diethylbarbic acid, N
, N-dimethylglycine, and the like.

Moreover, an acid anhydride can be used as the acid.

Examples of acid anhydrides include heptatalic anhydride, tetrahydrophthalic anhydride, hexahydroheptalic anhydride, 3,6-nindooxy-Δ4tetrahydroheptalic anhydride, tetrachlorophthalic anhydride, glutaric anhydride, maleic anhydride,
Talol maleic anhydride, a-phenyl maleic anhydride,
Examples include succinic anhydride and pyromellitic acid.

Also, as the acid, a polymer compound having an acidic group, such as a copolymer of a C1β-unsaturated dicarboxylic acid or anhydride and an ethylenically unsaturated comonomer, can also be used.

As the sulfite, alkali metal salts such as sodium, potassium, and lithium, alkaline earth metal salts such as magnesium, or ammonium salts are useful.

As anionic surfactants, higher alcohols (cm
~C22) Sulfuric ester salts [e.g., sodium salt of lauryl alcohol sulfate, sodium salt of octyl alcohol sulfate, ammonium salt of lauryl alcohol sulfate, "T-Pole B-81
J (trade name, manufactured by Shell Chemical), sodium chloride alkyl sulfate], aliphatic alcohol phosphate ester salts (e.g., cetyl alcohol phosphate natrilam salt, etc.), alkylaryl sulfonates (e.g., dodecylbenzenesulfonic acid sodium salt, isopropyl sodium salt, sinapthaline disulfonic acid sodium salt, metanitrobenzenesulfonic acid sodium salt, etc.), sulfonate salts of alkylamides (e.g., (+7H33CON(CI43)CI(2CH2S)
O3Na, etc.), sulfonic acid salts of dibasic fatty acid esters (eg, sodium sulfoconophosphate, dioctyl ester, sodium sulfosuccinate dioctyl ester, etc.). Among these, alkylnaphthalene sulfonates are particularly preferably used.

The amount of the compound of the present invention to be added to the back surface and/or overcoat layer of the negative 15th plate is determined experimentally by an amount corresponding to the amount consumed in developing the negative 15th plate, and such an amount is determined. Bye. The amount added is usually 0.05 to 1 g of acid.
/m” (when using an inorganic acid as the acid), sulfite is 0
．． 05-1 g/ra”, anionic surfactant is 0.0
It is in the range of 01-1 g/l.

To provide a back layer containing the compound of the present invention, a coating solution containing the above-mentioned polymer compound and the compound of the present invention dissolved in a solvent can be applied by spin coating, wire bar coating, dip coating, air knife coating, roll coating, or blade coating. It may be applied to the back side of the 13th plate by a method such as coating or curtain coating.

To provide an overcoat layer containing the compound of the present invention, a coating solution containing the polymer compound and the compound of the present invention is coated on the photosensitive layer of the 13th plate in the same manner as for the back side. Bye. The coating solvent is preferably a solvent that does not dissolve the photosensitive layer, such as water, methanol, ethanol, or propylene glycol.

The negative 15th plate according to the present invention is made by coating a photosensitive composition containing a diazo resin as a photosensitive component on a support commonly used as a support for the 13th plate. Examples of the support include those described in JP-A-62-175757, page 6, lower right column, line 15 to page 7, upper right column, line 11.

The negative 15th plate processed by the method of the present invention contains a diazo compound as a photosensitive component.

Examples of diazo compounds include diazonium salts and/or diazo resins which are condensates of p-diazodiphenylamine and formaldehyde, 7-enol salts or fluorocapric acid salts of p-diazodiphenylamine described in Japanese Patent Publication No. 7364/1983. etc., special public service 1977-4800
Diazo resin consisting of an organic solvent soluble salt of a copolycondensate described in No. 1, 2-methoxy-4-hydroxy-5-benzoylbenzenesulfonate of a condensate of p-diazodiphenylamine and formaldehyde, p- Examples include tetrafluorobol salts and hexafluorophosphates of condensates of diazodiphenylamine and formaldehyde. The present invention can be preferably applied to negative type 15 plates containing these as photosensitive components.

In addition to those in which these diazo compounds are used alone, the present invention can also be applied to those in which they are used in combination with various resins in order to improve the physical properties of the photosensitive layer. Examples of such resins include shellac, derivatives of polyvinyl alcohol, copolymers having alcoholic hydroxyl groups in side chains as described in JP-A-50-118802, and copolymers having alcoholic hydroxyl groups in the side chains as described in JP-A-55-155355. Examples include copolymers with phenolic hydroxyl groups in their side chains.

These resins include copolymers containing at least 50% by weight of structural units of the following format: R2 represents a hydrogen atom, a methyl group, an ethyl group, or a chloromethyl group, and n is an integer of 1 to 10) and 1 to 80 mol% of a monomer unit having an aromatic hydroxyl group, and acrylic acid. Included are polymer compounds having 5 to 90 mol% of ester and/or methacrylic acid ester monomer units and having an acid value of 10 to 200.

Additives such as dyes, plasticizers, components imparting printout performance, etc. can be added to the photosensitive layer of the negative 15th plate to which the developing method of the present invention is applied.

The amount of the photosensitive layer per unit area is at least 0°1-7
The present invention can be applied to the range of 100 g/m''.

In the method of the present invention, the positive type 25 plate, which can be commonly developed with a developer for both negative and positive plates, contains an 0-quinonediazide compound as a photosensitive component.

Specific examples of 0-quinonediazide compounds include, for example, JP-A-47-5303, JP-A-48-63802, and JP-A-48.
-63803, 49-38701, 56-10
No. 44, No. 56-1045, Special Publication No. 41-11222
No. 43-23403, No. 45-9610, No. 4
No. 9-17481, U.S. Pat. No. 2,797,213, U.S. Pat. No. 3,046,120, U.S. Pat.
, No. 454,400, No. 3,544゜323, No. 3,
No. 573,917, No. 3,674,495, No. 3,7
No. 85°825, British Patent No. 1,227,602, No. 1
, No. 251,345, No. 1,267.005, No. 1,
329,888, 1,330.932, and German Patent No. 854.890, and examples of acid-decomposable compounds include JP-A-60-37549, JP-A-60-10247,
Examples include those described in No. 60-3625 and the like, and the present invention can be preferably applied at least to positive type 25 plates using these compounds alone or in combination as photosensitive components.

These photosensitive components include 0-quinonediazide sulfonic acid ester or O-quinonediazidecarboxylic acid ester of an aromatic hydroxy compound and 0-quinonediazide sulfonic acid or 0-quinonediazidecarboxylic acid amide of an aromatic amino compound; - Those in which the quinonediazide compound is used alone, and those in which it is mixed with an alkali-soluble resin and this mixture is provided as a photosensitive layer are included.

Alkali-soluble resins include novolak-type phenolic resins, and specifically include phenol formaldehyde resins, cresol formaldehyde resins, phenol-cresol mixed formaldehyde resins, cresol xylenol mixed formaldehyde resins, and the like. Furthermore, as described in JP-A-50-125806, in addition to the above-mentioned phenol resin, (a phenol substituted with an alkyl group having 3 to 8 carbon atoms such as -butylphenol formaldehyde resin) or cresol and formaldehyde are used. A combination of a condensate and a condensate can also be applied.0
-The photosensitive layer containing a quinonediazide compound as a photosensitive component includes:
If necessary, additives such as dyes, plasticizers, and components imparting printout performance can be added.

In the present invention, the developer used repeatedly (hereinafter simply referred to as "developer") may be any known developer, but preferably the following.

The developer for developing the negative PS plate may be water or an aqueous solution containing a specific organic solvent and/or alkaline agent. Here, the specific organic solvent is one that can dissolve or swell the unexposed area (non-image area) of the above-mentioned photosensitive composition layer when contained in the developer, and that is An organic solvent having a solubility in water of 10% by weight or less is preferred. Examples of such organic solvents include those listed below in connection with the negative and positive developer. Among these organic solvents, ethylene glycol monophenyl ether and benzyl alcohol are particularly effective.

Examples of alkaline agents contained in the developer include sodium silicate, potassium silicate, potassium hydroxide, sodium hydroxide, lithium hydroxide, sodium or ammonium salts of dibasic or tertiary phosphoric acid, sodium metasilicate, and carbonate. Inorganic alkaline agents such as sodium and ammonia; mono-, di- or trimethylamine, mono-, di- or triethylamine, mono- or diisopropylamine, n-butylamine,
Examples include organic amine compounds such as mono-, di-, or triethanolamine, mono-, di-, or tripropanolamine, ethyleneimine, and ethylenediamine.

In order to improve the development performance, it is preferable that the negative PS plate developer contains a sulfite and an anionic surfactant to be contained in the back surface or overcoat layer of the negative PS plate. The amount of sulfite is 1-50gIQ
, the anionic surfactant is suitably in the range of 3 to 150 g/f2. In addition, amphoteric surfactants such as sodium N-methyl-N-pentadecylaminoacetate, and solubilizers such as alcohol ethyl ketone may be added to help dissolve organic solvents in water. can do.

The negative/positive developer is preferably an alkaline developer containing water as a main solvent (specifically, 50% by weight or more of the solvent is water).

Examples of the alkali agents include alkali silicates (potassium silicate, sodium silicate, etc.), potassium hydroxide,
Sodium hydroxide, lithium hydroxide, sodium triphosphate, sodium diphosphate, potassium triphosphate, potassium diphosphate, ammonium diphosphate, ammonium diphosphate, sodium metasilicate, sodium bicarbonate, carbonic acid Examples include inorganic alkaline agents such as sodium, potassium carbonate, ammonium carbonate, etc., organic alkaline agents such as triethanolamine and tetraalkyl hydroxide, and organic ammonium silicates. The content of alkaline agent in the developer is 0.05 to 20
The range of weight % is preferred, more preferably 0.1-10
% by weight.

The developer preferably contains a sulfite and an anionic surfactant from the beginning of repeated use. As the sulfite and the anionic surfactant, the compounds listed above as compounds to be included in the back surface or overcoat layer of the negative PS plate can be used. The concentration of sulfite in the developer is preferably in the range of 1 to 50 g/(i, the concentration of anionic surfactant is preferably 0.001 to 10% by weight,
More preferably, it is 0.01 to 1% by weight.

It is preferable that the developer contains an organic carboxylic acid. The organic carboxylic acid preferably has 6 to 6 carbon atoms.
20 aliphatic carboxylic acids, and a benzene ring or naphthalene ring substituted with a carboxyl group; aromatic carboxylic acids.

The aliphatic carboxylic acid is preferably an alkanoic acid having 6 to 20 carbon atoms, and specific examples include caproic acid, enantylic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, mystylic acid, palmitic acid, and stearic acid. etc., and particularly preferred are alkanoic acids having 6 to 12 carbon atoms. Also, fatty acids with double bonds in their carbon chains,
It may also have a branched carbon chain. In order to improve water solubility, the aliphatic carboxylic acid is preferably used as a sodium or potassium salt or an ammonium salt.

Specific compounds of aromatic carboxylic acids include benzoic acid, 0-chlorobenzoic acid, p-chlorobenzoic acid, 0-hydroquinebenzoic acid, p-hydroxybenzoic acid, p-ter
t-Butylbenzoic acid, O-aminobenzoic acid, p-aminobenzoic acid, 2,4-dihydroxybenzoic acid, 2.

5-dihydroxybenzoic acid, 2.3-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, 1-naphthoic acid, 2-naphthoic acid, etc. Among these, benzoic acids are particularly effective. The above aromatic carboxylic acid is preferably used as a sodium or potassium salt or an ammonium salt in order to improve water solubility.

There is no particular restriction on the content of aliphatic carboxylic acid or aromatic carboxylic acid added to the developer, but if it is less than 0.1% by weight, the effect will not be sufficient, and if it is more than 10% by weight, the further effect will not be obtained. It may be difficult to measure the improvement, or it may hinder dissolution when used in combination with other additives. Therefore, the amount added is preferably 0.1-10% by weight, more preferably 0.5-4% by weight.

Although additives may be added to the developer, organic solvents having a solubility in water of 10% by weight or less at 20'O are particularly effective for the purpose of the present invention.

Examples of organic solvents having solubility in water of 10% or less include carboxylic acid esters such as ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benzyl acetate, ethylene glycol monobutyl acetate, butyl lactate, and butyl levulinate. Ketones such as ethyl butyl ketone, methyl isobutyl ketone, and cyclohexanone; alcohols such as ethylene glycol monobutyl ether, ethylene glycol benzyl ether, ethylene glycol monophenyl ether, methylphenylcarhinol, n-amyl alcohol, and methyl amyl alcohol; These include alkyl-substituted aromatic hydrocarbons such as xylene; halogenated hydrocarbons such as methylene dichloride, ethylene dichloride, and monochlorobenzene. One or more of these organic solvents may be used.

The organic solvent is an excellent additive for improving the developability of both negative and positive PS plates, but at the same time it has the disadvantage of degrading the film in the image area for positive PS plates. It also has Since the positive-working PS plate does not undergo a crosslinking reaction like the negative-working 13th plate during exposure, the film deteriorates significantly when development is excessive, and the degree of deterioration becomes even greater in the presence of organic solvents. As mentioned above, it prevents the deterioration of the film during development of the positive PS plate, and
In order to develop the third plate well, it is effective to include a nonionic and/or cationic surfactant in the developer.

The pH of the developer for both negative and positive use is preferably 12 or higher,
More preferably, it is in the range of 12.5 to 13.5. When a negative type 13 plate is developed at such a high pH (pH 12 or higher), some types of plates may be stained during printing even though they are developed. The degree of staining is dependent on pH; the higher the pH, the more likely it is to stain.

In order to develop the negative type 13 plate well at such a high pH and eliminate stains during printing, it is very effective to include sulfite in the developer, and the addition of an anionic surfactant. The addition is particularly negative type 13 using a polymer with a low acid value.
It is highly effective in accelerating plate development.

Developer of the present invention (for negative PS plates and for both negative and positive)
may contain water-soluble or alkali-soluble organic and inorganic reducing agents.

Examples of organic reducing agents include phenolic compounds such as hydroquinone, methol, and methoxyquinone, and amine compounds such as phenylenediamine and phenylhydrazine. Examples of inorganic reducing agents include sodium sulfite, potassium sulfite, ammonium sulfite, and hydrogen sulfite. Sodium, sulfites such as potassium hydrogen sulfite, sodium phosphite, potassium ring phosphate, sodium ring hydrogen phosphate,
Examples include phosphates such as potassium hydrogen phosphite, sodium dihydrogen phosphite, and potassium hydrogen sulfite, hydrazine, sodium thiosulfate, and sodium dithionite. The reducing agent may be present in a range of at least 0.1-10% by weight.

Furthermore, the following additives can be added to the developer of the present invention in order to further improve the developing performance.

For example, NaCQ described in JP-A No. 58-75152,
KCQ+: Neutral such as Br, etc., JP-A-59-190952
EDTA described in the publication.

Chelating agents such as NT8, (Co(MHI)) described in JP-A No. 59-121336, complexes of *C(As, etc.), vinylbenzyltrimethylammonium chloride and sodium acrylate described in JP-A-56-142528; Amphoteric polymer electrolytes such as copolymers of JP-A-58-59
Inorganic lithium compounds such as lithium chloride described in Japanese Patent Publication No. 444, organic lithium compounds such as lithium benzoate described in Japanese Patent Publication No. 50-34442, JP-A-59-75255
Examples thereof include organometallic surfactants containing Si, Ti, etc., as described in Japanese Patent Application Laid-open No. 84241/1982, and organoboron compounds as described in Japanese Patent Application Laid-open No. 84241/1983.

The developer replenisher in the present invention suffers from fatigue due to the development process itself and fatigue due to aging (due to absorption of carbon dioxide gas in the air).
It may be of a composition that can restore the activity of the developer by replenishing the components in the developer that are consumed by the developer.

In the present invention, since the surfactant is replenished from the 15th plate by incorporating the surfactant into the negative 13th plate as described above, it is not necessary to include the surfactant in the developer replenisher.

The concentration of the alkaline agent in the developer replenisher is preferably higher than the concentration of the alkaline agent in the developer.

Its concentration preferably ranges from 0.2 to 30% by weight, more preferably from 0.5 to 10% by weight. It is preferable that the concentration of Sin is equal to or higher than that of the developer.

When using additives such as organic carboxylic acids, organic solvents, and reducing agents, their respective concentrations in the developer replenisher are preferably higher than those in the developer. Specifically, the concentration in the developer replenisher is suitably 1.2 to 1000 times the concentration in the developer.

〔Example〕

EXAMPLES The present invention will be specifically explained below with reference to Examples.

Example 1 A JIS 1050 aluminum plate with a thickness of 0-24 mm was degreased by immersing it in a 20% aqueous sodium phosphate solution.
The surface was electrochemically roughened in a dilute nitric acid solution, thoroughly washed, and then anodized in a dilute sulfuric acid solution to give 1.5 g/
An oxide film of m2 was formed on the surface of the aluminum plate.

The obtained aluminum plate was further immersed in an aqueous solution of sodium metasilicate for pore sealing, washed with water, and dried, then coated with the following photosensitive solution to a dry weight of 2.0 g/l, and further coated with the following photosensitive solution: The dry weight of the overcoat layer is 1
．． It was coated on the photosensitive layer so as to have a concentration of Og/l and dried to obtain a negative PS plate.

(Photosensitive liquid) Hexafluorophosphate of a condensate of p-diazodiphenylamine and paraformaldehyde...1 part by weight N-(4-hydroxyphenyl) methacrylamide copolymer (Example of Japanese Patent Publication No. 57-43890) 1)...100 parts by weight Hiftia Pure Blue BOH (manufactured by Hodogaya Chemical Co., Ltd., dye)...0.2 parts by weight Ethylene glycol monomethyl ether...100
Parts by weight (overcoat layer composition) Potassium sulfite...1 part by weight Polyvinyl alcohol...to weight water
...400 parts by weight Emulgen 147 ...0. I
Nlm (manufactured by Kako Co., Ltd., nonionic surfactant) The positive type 13 plate manufactured as above was used as a step tablet with a density of 0.15 steps (No. 2 manufactured by Eastman Kodasoku Co., Ltd.).
) for 20 seconds using a 3kW metal halide lamp.

This PS version is processed using an automatic processor PSK-910 (manufactured by Konica).
Using a negative-tone PS plate developer 5DN-21 (manufactured by Konica Corp.) diluted 4 times with water, a large number of sheets were processed continuously with the developer. 20 m2 of the above 15 plates per 112 developer solution
When the printing plates were printed at the start and end of the process, both results were good, and halftone dots from small dots to large fish were well reproduced.

Comparative Example 1 P of the 15th plate used in Example 1 excluding the overcoat layer
An S plate was prepared, exposed and developed in the same manner as in Example 1, and printing was performed on the plate at the start of the process and at the time when 15/201 plates were processed per 1Q of developer. was reproduced well; however, on the printing plate processed at 20ffi'/ffi, some of the shadows of the halftone dots were crushed during printing, and a good image could not be obtained.

Example 2 A JIS 1050 aluminum plate with a thickness of 0.24+ am was immersed in a 2% aqueous sodium hydroxide solution, degreased, and then electrochemically roughened in a dilute hydrochloric acid solution and thoroughly washed. After that, an anodizing treatment was performed in a dilute hydrochloric acid solution to form an oxide film of 2.5 g/a'' on the surface of the aluminum plate.

After washing the obtained aluminum plate with water and drying, a photosensitive solution having the following composition was applied to the backing layer with a dry weight of 2.5 g/m''.
It was applied to a weight of 1.0 g/m'' and dried to obtain a positive type 13 plate.The dimensions of the plate were 1003 x 800II+
+a and I;.

(Photosensitive liquid) Resorcinol-benzaldehyde resin 7-quinone-1
．． 2-diazide (2)-5-sulfonic acid ester (described in Example 1 of JP-A-56-1044) ...1 part by weight Talesol-phenol-formaldehyde resin ...3 is negative Naphthoquinone-1,2-diazide(2)-5-sulfonic acid ester of tert-butylphenol-benzaldehyde resin (Example 1 of JP-A-60-31138)
) ...0.1 part by weight Crystal violet ...0.05
Parts by weight (Dye manufactured by B, A, S, F, etc.) Ethylene glycol monomethyl ether: 20 parts by weight A transparent positive film was brought into close contact with this positive type 13 plate and exposed for 50 seconds using a 2kW metal halide lamp.

On the other hand, a 0.24n+m thick JIS 1050 aluminum plate was degreased by immersing it in a 20% aqueous sodium phosphate solution, electrochemically roughened in a dilute nitric acid solution, thoroughly washed, and then soaked in a dilute sulfuric acid solution. 1°5 after anodizing
An oxide film of g/m2 was formed on the surface of the aluminum plate.

The obtained aluminum plate was further immersed in an aqueous sodium metasilicate solution for pore sealing, washed with water, and dried, then coated with the following photosensitive solution to a dry weight of 2.0 g/ra''. The dry weight of the following back layer is 2.2g/
1 on the photosensitive layer, dry it and form a negative type 25
Got the edition.

(Photosensitive liquid) Hexafluorophosphate of a condensate of p-diazodiphenylamine and paraformaldehyde...1 part by weight N-(4-hydroxyphenyl)methacrylamide copolymer (Example of Japanese Patent Publication No. 1983-43390) 1) ... 100 parts by weight Hyftria Pure Blue B OH (Hodogaya Chemical Co., Ltd.)
Co., Ltd., dye)...0.2 parts by weight Ethylene glycol monomethyl ether...100 parts by weight (back layer composition) Pellex NBL...11t
J1 part (manufactured by Kako Co., Ltd., anionic surfactant) Polyhinylpyrrolidone...10 parts by weight water
...150 parts by weight Silicon oxide particles (diameter 2-5 μm) ...0.3 parts by weight (matting agent) A transparent negative film was adhered to this negative type 25 plate and exposed for 40 seconds with a 2kW metal halide lamp. .

On the other hand, the following developing solution was charged into an automatic developing machine PSK-9IO (manufactured by Konica Corporation).

(Developer) Perex NBL...15 parts by weight (manufactured by Kako Co., Ltd., anionic surfactant) Propylene glycol...5 parts by weight 2-Hydroquine-
3-naphthoic acid ... IO parts by weight p-tert
-Butylbenzoic acid...20 parts by weight 50% aqueous potassium hydroxide solution...50 parts by weight Emulgen 147...0.31 parts (
Manufactured by Kako Co., Ltd., nonionic surfactant) A potassium silicate
...36 parts by weight (manufactured by Nihon Kagaku Kogyo Co., Ltd.) Potassium sulfite ...12 parts by weight Water ...1500
Parts by Weight Finally, the pH was adjusted to pH 12.90 at 25°C.

A developer replenisher was prepared by diluting a concentrated solution with the following composition four times with water and replenishing it every 5 m2 of processing for 13 plates.

(Developer replenisher concentrate) Propylene glycol...5 parts by weight 2
-Hydroquine-3~naphthoic acid...10 parts by weight p-tert-butylbenzoic acid...
20 parts by weight 50% potassium hydroxide aqueous solution...
・60 parts by weight potassium sulfite...
・12 parts by weight A potassium silicate
...100 parts by weight (manufactured by Nihon Kagaku Kogyo Co., Ltd.) Water...250 parts by weight Finally, p) 1 was adjusted to pF 113.30 at 25°C.

In this way, a large number of negative type and positive type 15 plates were randomly processed. As a result, the negative type 25 version also has a positive type 15
The plate was also able to be developed stably. In addition, there was almost no variation in gradation even with reprints, and good printed matter was obtained. [Effects of the Invention] According to the present invention, an automatic developing machine is used to replenish the developer replenisher and the developer is used repeatedly. The stability of the developed finish in the development process of the negative 25th plate has been improved in the development process in which different solutions are used for a long period of time, and the same developer can be used for both the positive 15th plate and the negative 25th plate. When the developing process is performed, both the negative 25th plate and the positive 15th plate can be developed with a stable finish.

Claims (1)

[Claims] In a development processing method in which a negative-working photosensitive lithographic printing plate is imagewise exposed and then treated with a repeatedly used developer, an acid, a sulfite, and an anion interface are added to at least one of the back surface or overcoat layer of the negative-working photosensitive lithographic printing plate. 1. A method for developing a negative photosensitive lithographic printing plate, which comprises containing at least one selected from the group consisting of activators.