JPS62159148A - Developing solution composition for photosensitive lithographic plate and developing method - Google Patents

Abstract

PURPOSE:To obtain a developing solution high in development capacity and capable of obtaining always stable results by incorporating at least one of inorganic acids, organic acids, and their salts in an aqueous alkaline solution containing an alkaline agent, an organic solvent, and at least one of anionic surfactants and sulfites. CONSTITUTION:The developing solution is prepared by adding at least one of carbonic acid, phosphoric acid, hydrochloric acid, sulfuric acid, nitric acid, organic acids, and their salts into the alkaline solution containing at least one kind of alkaline agent selected from silicates, alkali metal hydroxides, quaternary ammonium hydroxides, and organic amines, the organic solvent having a solubility of <=10wt% in water at 20 deg.C, and at least one of anionic surfactants and sulfites, thus permitting the obtained developing solution composition to exhibit stable development performance even in the case of processing a large number of negative type and positive type PS plates with an automatic developing machine for a long time and high in developing capacity and unchangeable in development performance.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a developer composition used for developing a photosensitive lithographic printing plate (hereinafter referred to as 25th plate), and a method using the composition.
The present invention relates to a developing method for an 8th plate, and more specifically to a developer composition and a developing method that can commonly process a negative PS plate and a positive 15th plate.

[Background of the invention]

Conventionally, a negative-type PS plate and a positive-type PS plate have different l1rL compositions of compatible developers, and good development has been possible only with dedicated developers for each. Even if it were possible to develop using a developer other than a dedicated developer, a lithographic printing plate with sufficient performance would not be obtained, and it is virtually impossible to commonly process negative-working PS plates and positive-working 15th plates with the same developer. The current situation was that this was not possible. Japanese Unexamined Patent Publication No. 60-64351 describes an automatic developing machine (
A common developing method is described for developing both Nega-type 18th edition and Bon-type 18th edition. However, this method uses special developing solutions for each in separate developing baths, which are arranged side by side.
The development of the plate and the development of the positive 15th plate are performed consecutively, and they are not processed with a developing solution of the same formulation. Therefore, it is troublesome to manage each dedicated developer, and it is difficult to continue stable development for a long time. On the other hand, as a developer composition that can be used to develop both the negative type PS plate and the positive type 28 plate,
No. 130,741 proposes an aqueous alkaline developer for both negative and positive uses.

[Problems to be solved by the invention]

However, with these developers, 28
Although it is possible to choose the version, it is possible to use both positive and negative types.
Since the capacity of the developer is not sufficient, the plate is easily smudged due to poor development, and it is difficult to process a large number of sheets in a row.
The plates are commonly processed using an automatic developing machine, and a large number of 2 sheets are processed.
At present, it has been difficult to obtain a developer composition that can stably process five plates over a long period of time. An object of the present invention is to provide a common developer composition that can process both the negative 18th plate and the positive 28th plate. Another object of the present invention is to provide a 28-plate development method for processing negative and positive 23-plate plates with the common developer composition. Another object of the present invention is to exhibit stable development performance even when a large number of negative and one positive PS plates are processed alternately over a long period of time using an automatic developing machine, and to have a large development capacity. It is an object of the present invention to provide a developer composition and a developing method that can be used for both negative type and positive type 18 plates, and which can always obtain stable development results that do not easily fluctuate.

[Means to solve the problem]

As a result of various studies, the present inventors found that at least one alkali agent selected from silicates, alkali metal hydroxides, quaternary ammonium hydroxides, and organic amines;
Carbonic acid, phosphoric acid, hydrochloric acid, sulfuric acid, nitric acid and organic acids or their salts are added to an alkaline aqueous solution containing at least one of an organic solvent having a solubility in water of 10% by weight or less and an anionic surfactant and a sulfite at °C. It has been found that the above object can be achieved by a developer 111 for photosensitive planographic printing plates common to both negative and positive types and a developing method containing at least one selected from the following. The present invention will be explained in more detail below. The developer composition for photosensitive planographic printing plates that can be used for both negative and positive types of the present invention contains the above-mentioned components, but there are few examples of alkaline agents used in the present invention. For example, silicates such as sodium silicate, potassium silicate, lithium 11ate, ammonium silicate, sodium metasilicate, potassium metasilicate, alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, lithium hydroxide,
Quaternary ammonium hydroxides such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetra-bibutylammonium hydroxide, trinotylbennolammonium hydroxide, phenylmethylethylallylammonium hydroxide, and mo/ethylammonium hydroxide. , noethanolamine, triethylamine, and the like, and at least one alkaline agent selected from these is added in an amount of 0.05 to 20% based on the total developer composition;
It is preferably used in a content of 0.1 to 10% by weight. These alkaline agents can be used in combination so that development can be carried out with the pl+ of the developer at a desired value, in the present invention plllo, in the range of 5 to 13.5. Next, the organic solvent used in the present invention is 20
carboxylic acid esters having a solubility in water of 10 fflfi% or less at °C, such as ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benzyl acetate, ethylene glyfur monobutyl acetate, butyl lactate, butyl levulinate; Ketones such as ethyl butyl ketone, methyl isobutyl ketone, cyclohexanone; ethylene glycol motuptyl ether, ethylene glycol benol ether, ethylene glycol monophenyl ether, propylene glycol monophenyl ether, benzine alcohol, methylphenyl carbyl ether , n-7 methyl alcohol, and methyl amyl alcohol; alkyl-substituted aromatic hydrocarbons such as xylene; and halogenated hydrocarbons such as methylene nochloride, ethylene dichloride, and monochlorobenzene. One or more of these organic solvents may be used. Among these organic solvents, ethylene glycol monophenyl ether, ethylene glycol benol ether, propylene glycol monophenyl ether and benol alcohol are particularly preferred. The amount of these organic solvents added is effective in a relatively small amount, but the content in the developer composition is 0.1 to 5.0% by weight, 1% by weight,
More preferably, it is 0.3 to 2.0% by weight. In addition to the above, the developer ML composition of the present invention further contains at least one of an anionic surfactant and a sulfite. Examples of the above-mentioned anionic surfactants include higher alcohol (C6-C22) sulfate ester salts [e.g., sodium salt of lauryl alcohol sulfate, sodium salt of octyl alcohol sulfate, ammonium salt of lauryl alcohol sulfate, [Teaball 1l-81J (trade name, manufactured by Shell Chemical Co., Ltd.), sodium chloride alkylsulfonate, etc.], aliphatic alcohol phosphate ester salt M (e.g., sodium salt of cetyl alcohol phosphate ester, etc.), alkylaryl sulfonate M ( For example, sodium salt of dodecylbenzenesulfonic acid, sodium salt of isopropylnaphthalenesulfonic acid, sodium salt of nona7talin disulfonic acid, sodium salt of metanitrobenzenesulfonic acid, etc.), sulfonate salts of alkylamides B (for example, C17H* j
CON CH2CH2S O3N a, etc.), 2CH. There are sulfonate salts of basic fatty acid esters (eg, sodium sulfosuccinate dioctyl ester, sodium sulfosuccinate dihexyl ester, etc.), and among these, sulfonate salts are particularly preferably used. Among the above sulfonate salts, flukylnaphthalene sulfonate salts are preferred, and mono-, di-, or tri-substituted sodium isopropylnaphthalene sulfonate, sodium butylnaphthalene sulfonate, and the like are particularly effective. In the present invention, the content of these anionic surfactants in the developer composition is preferably in the range of 0.5 to 10% by weight. In addition, the above-mentioned sulfite is a water-insoluble diazo O (which has the function of dissolving fat in an aqueous solution, and is used for a long period after production, especially in the development of a lithographic printing plate consisting of a photosensitive layer combined with a hydrophobic resin. Printing plates without stains can be made even from aged plate materials. Useful sulfites include, for example, alkali metal salts such as natochrome, kali, lithium, alkaline earth metal salts such as magnesium, and ammonium salts. The content of these sulfites in the developer composition is 0.
It is suitable to use it in a range of 1 to 5 rfL amount %, more preferably 0.3 to 3 rfL weight. In addition to the above-mentioned components, the developer composition of the present invention is characterized by containing the following acids or salts of acids in order to improve processing ability and stability of developability. Examples of the above acids or acid salts used in the present invention include carbonates, carbonates such as sodium carbonate, potassium carbonate, sodium potassium carbonate, lithium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, phosphoric acid, polyphosphoric acids, Phosphates such as potassium phosphate, dipotassium hydrogen phosphate, potassium dihydrogen phosphate, sodium phosphate, sodium hydrogen phosphate, sodium dihydrogen phosphate, ammonium phosphate, ammonium hydrogen phosphate, sodium, potassium polyphosphate, hydrochloric acid or sodium chloride, potassium chloride, Hydrochlorides such as lithium chloride, calcium chloride, and ammonium chloride; sulfates such as sulfuric acid or potassium sulfate; sodium sulfate; potassium sulfate; sodium hydrogen sulfate; and ammonium sulfate; nitric acid or nitrates such as potassium nitrate, sodium nitrate, lithium nitrate, and ammonium nitrate. Furthermore, acetic acid, oxalic acid, tartaric acid, benzoic acid, succinic acid, citric acid, 1-nongoic acid, lactic acid, tannic acid, glycine, 7-lanine, sarcosine, valine, leucic acid, ascorbic acid,
Organic acids such as levulinic acid, l)-)ruylic acid, p-)luenesulfonic acid, 2-pyridinecarboxylic acid, heptatalic acid, noethylbarbic acid, N,N-tumethylglycine, or salts thereof; Examples include sodium salts, potassium salts, lithium salts, ammonium salts, and the like. Among these acids or salts, carbonic acid, phosphoric acid, hydrochloric acid or alkali metal salts thereof, organic carboxylic acids or organic carboxylic acid salts, etc. are preferable, and more specifically,
Potassium carbonate, sodium carbonate, dipotassium hydrogen phosphate,
Examples include inorganic salts such as tripotassium phosphate, disodium hydrogen phosphate, trisodium phosphate, potassium chloride, and sodium chloride, as well as organic carboxylic acids such as acetic acid, citric acid, and glycine, or their alkali metal salts or ammonium salts. can. These acids or salts according to the present invention can be used alone or in combination of two or more together with the alkali agent described above, and the amount of 0.5
~IO weight%, preferably 1.0 to 8.0% by weight. Further, the following additives can be added to the developer used in the present invention in order to further improve the development performance. For example, EDTA described in VF No. 58-190952,
Chelating agents such as NT8, (Co(NII*))-CI-'% complex described in JP-A-59-121336,
N-tetramethyl-N. Anionic or amphoteric surfactants such as N-hydroxyethylbetaine, nonionic surfactants such as tetramethyldecynediol described in U.S. Pat. No. 4,374,920, and Cationic polymers such as p-dimethylamino/methylpolystyrene chloride quaternized products, amphoteric electrolyte polymers such as copolymers of vinylbennortrimethylammonium chloride and sodium acrylate described in JP-A-56-142528, Reducing inorganic salts such as sodium phosphite described in JP-A-57-192952, organic lithium compounds such as lithium benzoate described in JP-A-50-34442, JP-A-57-1929
Examples include organometallic surfactants containing Si, Ti, etc., as described in Publication No. 9-75255. The developer composition according to the present invention has a p of 10.5 to 13.5 when used to achieve the object of the present invention.
It is characterized by having an H value. Also, its salt content is 0
．． Preferably, it is between 5 and 10 weight percent. A method for developing a photosensitive lithographic printing plate using the developer composition of the present invention as described above will be described later, but it is preferable to use an automatic developing machine. The photosensitive composition of the negative type and positive type 28 plates used in the present invention contains a photosensitive substance as an essential component, and the physical and chemical properties of the photosensitive substance can be changed by exposure or subsequent development treatment. For example, there is a difference in solubility in a developing solution due to exposure, a difference in intermolecular adhesive strength before and after exposure, and a difference in affinity for water and oil due to exposure or subsequent development processing. It is possible to use a material that produces an image, a material that can form an image area by an electrophotographic method, a material that has a multilayer structure as described in JP-A-55-166645, and the like. Typical photosensitive substances include photosensitive noazo compounds, photosensitive and compounds, compounds with ethylenically unsaturated double bonds, epoxy compounds that polymerize with acid catalysts, silyl ether polymers that decompose with acids, and C-0-
Examples include compounds having a C-group. 0-
Examples include quinonenoanodo compounds, acid-decomposable ether compounds, and ester compounds. In addition, aromatic diazonium salts and the like can be cited as negative-type compounds whose solubility decreases upon exposure to light. Specific examples of 0-quinonenoanodo compounds and examples, LetSpec f1 [47-530'1lJ148-63
No. 11102, No. 48-63803, No. 49-387
No. 01, No. 56-1044, No. 56-1045, Special Publication No. 41-11222, No. 43-28403, No. 4
Publications No. 5-9610 and No. 49-17481, U.S. Patent Nos. 2,797,213 and 3,046,120,
3,188,210, 3,454,400, 3,544,323, 3,573,917, 3
, 674,495, 3°785, 825, British Patent No. 1,227.602, British Patent No. 1,251,345,
1.26), 005, 1.329.888, 1.333<1,932, German Patent 854,890
JP-A No. 60-37549, JP-A No. 60-10247, JP-A No. 60-3625 and other publications or specifications, and these compounds can be used alone or in combination to form photosensitive components. The present invention can be preferably applied at least to the 15th edition used as the 15th edition. These photosensitive components contain 0-
Quinonediazide sulfonic acid ester or 0-quinonediatide carboxylic acid ester and aromatic amino compound 0-quinonediazide sulfonic acid or 0-quinonediatcarboxylic acid amide are included; It includes those used in the above, and those mixed with an alkali-soluble resin and provided with this mixture as a photosensitive layer. Alkali-soluble resins include novolac type phenolic resins, and specifically include phenol formaldehyde resins, cresol formaldehyde resins, phenol-cresol mixed formaldehyde resins, cresol xylene/ol mixed formaldehyde resins, and the like. Furthermore, as described in JP-A-50-125806, in addition to the above-mentioned phenol resins, 3-carbon resins such as t-butylphenol formaldehyde resins are used.
A combination of a phenol substituted with an alkyl group of ~8 or a condensate of cresol and formaldehyde can also be used. If necessary, additives such as dyes, plasticizers, and components imparting printout performance can be added to the photosensitive layer containing an 0-quinonediaside compound as a photosensitive component. The amount per unit area of the photosensitive layer containing the 0-quinonediazide compound as a photosensitive component is preferably about 0.5 to 7 g/Ifi2.
The present invention can be applied to the range of The image exposure of the positive-working photosensitive lithographic printing plate to which the developing method of the present invention is applied does not need to be particularly changed and may be carried out according to a conventional method.A typical photosensitive component of the negative-type photosensitive layer is a diazo compound, For example, diazinium salts and/or diazo resins which are condensates of p-diazophenylamine and formaldehyde, 7-enol salts or fluorocapric acid salts of p-diazodiphenylamine described in Japanese Patent Publication No. 7364/1980, etc. 3-methoxydiphenylamine-4 described in Publication No. 49-48001
- Diazo resin consisting of an organic solvent soluble salt of a copolycondensate of diazonium chloride, 4-nitrodiphenylamine and formaldehyde, 2-nodoquine-4-hydroxy-5-benzoylbenzene, a condensate of p-diazodiphenylamine and formaldehyde Examples include sulfonate, tetrafluoroborate of a condensate of p-diazodiphenylamine and formaldehyde, and hexafluoroliy91 salt.In addition to using these diazo compounds alone, we investigated the physical properties of the photosensitive layer. The present invention can also be applied to materials that are used in combination with various resins to improve the quality of the product. Examples of such resins include shellac, derivatives of polyvinyl alcohol, etc. These resins include copolymers having alcoholic hydroxyl groups in their side chains, and copolymers having phenolic hydroxyl groups in their side chains, which are described in JP-A-55-155355. A copolymer containing at least 650% by weight of structural units of the general formula
R1 + CIl□-C+ C00→CIIzCtlO) nH (wherein, R+ represents a hydrogen atom or a methyl group, 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 monomer units having an aromatic hydroxyl group, and 5 to 90 mol% of acrylic ester and/or methacrylic ester monomer units, and an acid value of 10 to 200. Includes polymer compounds with The photosensitive layer of the negative 28 plate to which the developing method of the present invention is applied can further contain additives such as dyes, plasticizers, components that provide printout performance, and the like. The amount per unit area of the photosensitive layer is at least 0.1 to 7
The present invention is applicable to the range of g/z2. Supports used in the above 25th edition include paper, plastic (e.g. polyethylene, polypropylene, polystyrene, etc.), laminated paper, aluminum (including aluminum alloys), zinc, metal plates such as lagoon, diacetic acid, etc. Films of plastics such as cellulose, cellulose triacetate, cellulose propionate, polyethylene terephthalate, polyethylene, polypropylene, polycarbonate, polyvinyl acetal, etc., paper or plastic films laminated or vapor-deposited with metals such as those mentioned above, aluminum or chrome plated. Among them, aluminum and aluminum-coated composite supports are preferred. Further, the surface of the aluminum material is desirably subjected to an 11-sided treatment for the purpose of increasing water retention and improving adhesion to the photosensitive layer. Examples of the surface roughening method include generally known methods such as brush polishing, ball polishing, electrolytic etching, chemical etching, liquid honing, and sandblasting, and combinations thereof. Preferably, brush polishing, electrolytic etching, and chemical etching are used. Target etching and liquid honing are mentioned, among which roughening methods involving the use of electrolytic etching are particularly preferred. The electrolytic bath used in electrolytic etching is an aqueous solution containing an acid, an alkali, or a salt thereof, or an aqueous solution containing an organic solvent. Electrolytes containing these salts are preferred. Further, the roughened aluminum plate is desmutted with an acid or alkali aqueous solution, if necessary. It is desirable that the aluminum plate thus obtained be anodized, and particularly preferably, a method of treatment in a bath containing sulfuric acid or phosphoric acid can be mentioned. Further, if necessary, a sealing treatment and other surface treatments such as immersion in an aqueous solution of potassium fluorinorconate can be performed. Various conventionally known methods can be used to develop the image-exposed 28 plate using the developer described above. Specifically, the method includes a method in which a developing solution is sprayed from a number of nozzles onto the image-exposed photosensitive layer of the 28-plate, a method in which the developer is immersed in a large amount of the developer, and a method in which the photosensitive layer of the 28-plate image is exposed using a sponge moistened with the developer is used.
The methods include wiping the photosensitive layer of the plate, and applying a developer to the photosensitive N surface of the 28 plate using a roller. Among these methods, the same method or different methods can be used multiple times within the development zone and between development zones. rlL can be developed in combination. In addition, after the developer has been applied to the photosensitive layer of the 28th plate in this way, or with the 28th plate immersed in the developer, the surface of the photosensitive layer can be rubbed lightly with a blan or the like.Development conditions can be appropriately determined by a person skilled in the art depending on the above-mentioned development method, for example, the developer temperature, processing time, etc. The developer temperature is generally 5°C.
The temperature range is from 60°C to 60°C, preferably from 10°C to 45°C, more preferably from 25°C to 35°C. Further, in the present invention, the processing time of the 28th plate in the development zone is preferably 10 seconds to 90 seconds. Further, the developer replenisher may be replenished in response to exhaustion of the developer due to the development process of these 28 plates or absorption of carbon dioxide in the air. Various conventionally known developing auxiliary liquids can be used, and various conventional methods can be used for replenishing the developing replenisher. In addition to the development process described above, the development process used in the method of the present invention includes, if necessary, after the development process, a development stop process (the stop process solution includes a disposable system or a cyclic system), and an insensitivity process. Each individual treatment step of the desensitization treatment step, a development stop treatment step followed by a desensitization treatment step, a treatment step that combines the development treatment step and the desensitization treatment, or a development stop treatment step and the desensitization treatment step. For example, the treatment process described in Japanese Patent Application Laid-Open No. 54-8002 may be included.

【Effect of the invention】

According to the present invention, the developer composition for photosensitive planographic printing plates common to both negative and positive types includes an alkaline agent, 20%
At least one selected from inorganic acids, organic acids, or their salts is added to an alkaline aqueous solution containing at least one of a growth solvent, an anionic surfactant, and a sulfite having a solubility in water of 10 ffl volume % or less at °C. Because of this, even if a large number of negative and positive photosensitive lithographic printing plates are processed one after the other for a long time by the automatic developer Song Dynasty, it exhibits stable development performance and has a large developing capacity. , consistently stable development results were obtained.

【Example】

Hereinafter, the present invention will be explained in detail with reference to Examples. (Example 1) A JIS 1050 aluminum plate with a thickness of 0.24 scraps was immersed in a +7 um aqueous solution and treated with chlorine, and then electrochemically roughened in a dilute nitric acid solution. After planarization and thorough cleaning, anodization treatment was performed in a dilute sulfuric acid solution to form an oxide film of 2.5 g (7 x 2) on the surface of the aluminum plate. After washing and drying the aluminum plate treated in this way, a photosensitive solution having the following composition was applied to a dry mold f;12.
Apply to 5fI/x2, dry and use positive ps
Got the edition. (Photosensitivity Q) A large number of positive type 28 plates thus obtained were prepared, a transparent positive film was adhered thereto, and exposure was performed for 60 seconds from a distance of 70 CI 11 using a 2 kilowatt metal halide lamp. On the other hand, a negative 25th plate was prepared as follows. A JIS 1050 aluminum plate with a thickness of 0.24xx was degreased by immersing it in a +7um aqueous solution (20% phosphoric acid),
The surface was electrochemically roughened in a dilute hydrochloric acid solution, thoroughly washed, and then anodized in a dilute sulfuric acid solution to 1.5y/z2.
An oxide film was formed on the surface of the aluminum plate. The aluminum plate thus treated was further immersed in an aqueous sodium metasilicate solution for pore sealing, washed with water, and dried, after which a photosensitive solution having the following composition was applied to dry type 1i2.
It was coated so that h/z2 was obtained and dried to obtain a negative type 15 plate. (Photosensitive solution) A large number of negative-type photosensitive lithographic printing plates thus obtained were prepared, a transparent net film was adhered thereto, and exposure was performed for 30 seconds from a distance of 70 cm using a 2 kilowatt metal halide lamp. In addition, 30% of the following aqueous alkaline developer was added to the development processing section of an automatic processor PSP-860 (manufactured by Konishiroku Photo Industry Co., Ltd.).
1, and the developer temperature was adjusted to 25°C. (Aqueous alkaline developer) The pl+ of the above developer was 12.4 at 25°C. In addition, the conveyance speed of this automatic developing machine is 45 times as long as the developing time.
In order to perform water washing as a process after development processing, the circulation washing tank was filled with water. It was processed by passing it through a developing machine. Under the above processing conditions, the negative type 25 plate is 1003JIRX 800zy
It was able to process up to 102 sheets of the same size, and up to 87 positive type 28 plates of the same size. In this way, it is developed and washed with water! When a gum solution was applied to the prepared lithographic printing plates and printing was performed, high-quality printed matter with no stains in the non-image areas was obtained for each printing plate. (Comparative Example 1) A test similar to Example 1 was conducted except that the developer shown below was used. (Aqueous alkaline developer) The p+1 of the above developer was 12.4 at 25°C. As a result, the negative PS plate that can be processed and that produces high-quality prints with no stains in non-image areas is 1003z.
Up to 78 sheets of zX 800yz size, and up to 48 sheets of positive type 28 of the same size. (Example 2) A photosensitive solution having the following composition was coated on the same aluminum support as the positive type 28 plate in Example 1 at a dry weight of 22 g/shoulder 2, and dried to obtain a positive type 28 plate. Ta. (Photosensitive solution) A large number of positive type 28 plates thus obtained were prepared, a transparent positive film was adhered thereto, and exposure was performed for 45 seconds from a distance of 70 mm using a 2 kilowatt metal halide lamp. On the other hand, the negative type 28 plate was produced as follows. A photosensitive solution having the following composition was coated on the same aluminum support as the Neygps plate in Example 1 to give a dry type f: L of 1.8 g, 7 x 2, and dried to obtain a negative type 28 plate. (Photosensitive solution) A large number of negative 28 plates thus obtained were prepared, a transparent negative film was adhered thereto, and exposure was performed for 3° from a distance of 70 cm using a 2 kilowatt metal halide lamp. Next, 301 of the following water-washed alkaline developer was charged into the development processing section of the same automatic processor as in Example 1, and the developer temperature was adjusted to 27°C. (Aqueous alkaline developer) Next, set the conveyance speed of this automatic developer so that the development time is 20 seconds, and add the following surfactant aqueous solution to the rinse tank to perform rinsing as a step after development. I put 15&. (Surfactant aqueous solution) 18 exposed in the same manner as in Example 1 under these conditions.
When I processed the plate, the negative type 25 plate was 1003zi+X.
It was able to process up to 120 sheets of 800zz size, and up to 95 sheets of the same size positive type 28 plate. When a lithographic printing plate that had been developed and rinsed in this manner was coated with a mulch solution and printed, high-quality printed matter with no stains in the non-image areas was obtained in all cases. (Example 3) A test similar to Example 1 was conducted except that the following developer was used. (Aqueous alkaline developer) 1) 11 of the above developer was 12.2 at 25°C. The negative mold obtained by processing is 1033 Jl shoulder x 800
It can process up to 100 sheets of 1111 size, and up to 75 sheets of positive type 28 plate of the same size, and when printing, all printing plates produced high quality prints with no stains in the non-image area. It was done.

Claims (2)

[Claims] (1) At least one alkaline agent selected from silicates, alkali metal hydroxides, quaternary ammonium hydroxides, and organic amines, an organic solvent with a solubility in water of 10% by weight or less at 20°C, and an anion. It is characterized in that an alkaline aqueous solution containing at least one of a surfactant and a sulfite contains at least one selected from carbonic acid, phosphoric acid, hydrochloric acid, sulfuric acid, nitric acid, and organic acids or salts thereof. A developer composition for photosensitive planographic printing plates common to both negative and positive types. (2) A negative-working photosensitive planographic printing plate and a positive-working photosensitive planographic printing plate are prepared using the developer composition for photosensitive planographic printing plates.
1. A method for developing a photosensitive lithographic printing plate, characterized in that processing is carried out in common in H10.5 to H13.5.