JPS62175757A - Liquid developer and developing method for photosensitive lithographic printing plate - Google Patents

Abstract

PURPOSE:To satisfactorily and quickly develop negative type and positive type photosensitive lithographic printing plates with one developing soln. by incorporating a cationic surface active agent in a specific range into the liquid developer. CONSTITUTION:The cationic surface active agent is incorporated at 0.001-10wt% into the liquid developer and the liquid developer is used in a 11.5-13.5pH range in the case of using the aq. alkaline liquid developer and commonly processing the negative type photosensitive lithographic printing plate and positive type photosensitive lithographic printing plate each having an image forming layer on a base. The amt. of the cationic surface active agent to be added is particularly preferably in a 0.01-1wt% range. The effect is low if the amt. of <0.001wt%. The development is suppressed and good performance is not obtainable if the content exceeds 10wt%. The more adequate common development is executed by incorporating 0.1-10wt% org. solvent having <=10wt% solubility with water at 20 deg.C into said liquid developer. The performance of the common development is further improved by adding a sulfite and/or anionic surface active agent to the liquid developer.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a developer and a developing method for photosensitive lithographic printing plates, and in particular to negative-working photosensitive lithographic printing plates and positive-working photosensitive lithographic printing plates. The present invention relates to a developer and a developing method that can commonly develop a plate well.

[Prior art]

Conventionally, negative-type photosensitive lithographic printing plates and positive-type photosensitive lithographic printing plates have different developer compositions, and suitable development has been possible only with the respective developers.

Even if development could be performed using a developer other than a dedicated developer, a lithographic printing plate with sufficient performance could not be obtained, and a negative-type photosensitive lithographic printing plate and a positive-type photosensitive lithographic printing plate with the same formulation could not be obtained. At present, it is virtually impossible to carry out common processing using a developing solution.

JP-A No. 60-64351 describes a common developing method in which both a negative-working photosensitive plain printing plate and a positive-working photosensitive lithographic printing plate are developed using one automatic developing machine. but,
In this technology, development for negative-type photosensitive lithographic printing plates and development for positive-type photosensitive lithographic printing plates are performed sequentially by placing each developer in a separate developing bath. They are not developed with the same developer solution.

Therefore, since dedicated developing solutions are used for each, solution management is troublesome and it is difficult to perform stable development for a long time.

On the other hand, a technology to perform common development using one developer was introduced in Japanese Patent Application Laid-open No. 6
It is disclosed in Japanese Patent No. 0-130741. This developer consists of an organic solvent of ethylene glycol monophenyl ether or ethylene glycol monobennorether, a silicate, an alkali metal hydroxide, an anionic surfactant, and a tetraborate. However, when common development is performed with such a developer, ink stains may occur during printing with a negative photosensitive lithographic printing plate. Furthermore, in the case of positive-working photosensitive lithographic printing plates, the development results were extremely variable, and a portion of the image area was easily eroded and chipped during development. This tendency is more pronounced when the development time is slightly extended or when the development temperature is slightly higher than the predetermined temperature, resulting in loss of detail in the image or when printing This may cause poor printing durability.

The inventors of the present invention were able to achieve common development using the technique described in Japanese Patent Application No. 166250/1982, but the above-mentioned phenomenon of deterioration of the image area of a positive-working photosensitive lithographic printing plate was sufficiently prevented. was not resolved.

[Purpose of the invention]

An object of the present invention is to provide an excellent developer and developing method that can satisfactorily develop negative-working and positive-working photosensitive lithographic printing plates with a single developer.

Another object of the present invention is to provide a developer and a developing method that have excellent development stability and a wide range of processing latitude needs.

Another object of the present invention is to provide a developer and a developing method that allow a plate with excellent printing performance to be obtained.

Another object of the present invention is to provide an excellent developing solution and developing method that can rapidly develop negative-working and positive-working photosensitive lithographic printing plates.

[Structure of the invention]

As a result of extensive studies, the present inventors found that when negative-working photosensitive lithographic printing plates and positive-working photosensitive lithographic printing plates having an image forming layer on a support are commonly processed using an aqueous alkaline developer, 0.001 cationic surfactant in developer
By containing the developer in an amount of ~10% by weight, and by using this developer in a pllll range of 5 to 13.5, the above object of the present invention could be achieved.

Furthermore, more suitable common development could be carried out by adding 0.1 to 10% by weight of an organic solvent having a solubility in water of 10% by weight or less at 20° C. to the developer.

Furthermore, the performance of common development could be further improved by adding a sulfite salt and/or an anionic surfactant to the developer.

The developer in the present invention contains a cationic surfactant at 0.00%.
001 to 10% by weight, and an alkaline agent, and has a kpu in the range of 11.5 to 13.5. Here, "having water as the main solvent" means that at least 50% of the solvent of the developer is
% by weight is water.

Various cationic surfactants can be used in the present invention. Cationic surfactants are broadly classified into amine type and quaternary ammonium salt type, and any of these can be used in the present invention.

Examples of amine types include polyoxyethylene alkylamine, N-alkylpropyleneamine, N-furkylpolyethylenepolyamine, N-alkylpolyethylenepolyamine trimethyl sulfate, alkyl biguanide, long chain amine oxide, alkyl biguanide, 1-hydroxy Ethyl-2-furkylimigzolin, 1-7cetylaminoethyl-2-furkylimigzolin, 2-furkyl-4-
Examples include methyl-4-hydroxymethyloxazoline.

Examples of quaternary ammonium salts include chain primary amine salts, alkyltrimethylammonium salts, noalkylnomethylethylammonium salts, alkylnomethylammonium salts, alkyldimethylbennolammonium salts, alkylpyridinium salts, Alkylquinolinium salt, alkylisoquinolinium salt, alkylpyridinium sulfate, stearamidemethylpyridinium salt, acylamide/ethyldiethylamine salt, acylaminoethylmethylnoethylammonium salt, alkylamidopropyldimethylbenzylammonium salt, fatty acid polyethylene polyamide , acyl 7-mi/ethylpyridinium salt, acylcolaminoformylmethylbirizonium salt, stearoxymethylpyridinium salt, fatty acid triethylamine, fatty acid triethylamine formate, trioxyethylene fatty acid triethanolamine, fatty acid dibutylamine 7 ethanol, cetyloxymethylpyridinium salt, p
-Inoctyl 72/xyethoxyethyldimethylbenzyl ammonium salt and the like. ("Alkyl" in the above compound examples refers to a straight chain or partially substituted alkyl having 6 to 20 carbon atoms, and specifically, straight chain alkyl such as hexyl, octyl, cetyl, stearyl, etc.) Among these, water-soluble quaternary ammonium salt type cationic surfactants are particularly effective, and among them, alkyltrimethylammonium salts, alkyldimethylbennolammonium salts, ethylene oxide addition ammonium salts, etc. suitable. Further, a polymer having a cationic component as a repeating unit is also a cationic surfactant in a broad sense, and the cationic surfactant of the present invention has a golden color.

In particular, a polymer containing a quaternary ammonium salt obtained by copolymerizing with a lipophilic moamer can be suitably used.

The amount of the above cationic surfactant added is 0.001 to 1
The range is 0% by weight, more preferably 0.01% to 1% by weight. If the amount added is less than 0.001% by weight, the effect of the present invention will be weak, and if it exceeds 10% by weight, development will be suppressed and good performance will not be obtained. Further, the weight average molecular weight is in the range of 300 to 50,000, particularly preferably in the range of 500 to 5,000. These cationic surfactants may be used alone or in combination of two or more.

The developer according to the present invention is used to align the development balance between a negative-working photosensitive lithographic printing plate and a positive-working photosensitive lithographic printing plate, and to perform the development more quickly. In order to make it possible to process a wider variety of photosensitive lithographic printing plates with a common developer, it is preferable to contain the following additives.

First, preferred additives include organic solvents having a solubility in water of 10% by weight or less at 20°C. By including this additive, the above effects can be enhanced.

The solubility in water at 20°C used in the present invention is 10
Examples of organic solvents with a weight percent or less include ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benyl acetate,
Carboxylic acid esters such as ethylene glyfur monobutyl acetate, butyl lactate, butyl levulinate; Ketones such as ethyl butyl ketone butyl ketone, cyclohexanone; ethylene glycol mo/butyl ether thylene glycol benzyl ether, ethylene glycol
Alcohols such as homo/phenyl ether, benzyl alcohol, methylphenylcarbyl, n-7 methyl alcohol, methyl amyl alcohol; alkyl-substituted aromatic hydrocarbons such as xylene; methylene chloride, ethylene dichloride, monochlorobenzene There are halogenated hydrocarbons such as One or more of these organic solvents may be used. Among these organic solvents, ethylene crico homo/phenyl ether, ethylene glycol benzyl ether and benzyl alcohol are particularly preferred.

This organic solvent is an excellent additive for improving the developability of both negative and positive plates, but at the same time it degrades the film in the image area of positive photosensitive planographic printing plates. It also has the disadvantage of softening the image. Because positive-working photosensitive lithographic printing plates do not undergo a crosslinking reaction during exposure like negative-working photosensitive lithographic printing plates, they are subject to significant deterioration when development is excessive, and the degree of deterioration is even greater in the presence of organic solvents. becomes larger. The inventors of the present invention f. As a result of the study, we found that in order to prevent deterioration during development of bond-type photosensitive lithographic printing plates and to improve development of negative-type photosensitive lithographic printing plates, a cationic surfactant was added to the developer solution. ．． It has been found that the content can be in the range of ooi to 10% by weight.

In particular, cationic surfactants have a solubility power of 1 in water.
In the presence of 0% by weight or less of an organic solvent, it is effective in preventing film deterioration and image softening of positive-working photosensitive lithographic printing plates, and has almost no adverse effect on negative-working photosensitive lithographic printing plates. Shows excellent effects when both plates are developed in common.

The pll of the developer according to the present invention is in the range of 11.5 to 13.5, but when a negative photosensitive lithographic printing plate is developed at such a high pH, some types of plates may not print even after being developed. Sometimes stains may occur.

The degree of contamination is p1 dependent, and the higher the pi, the more likely it is to be contaminated. In order to develop negative photosensitive lithographic printing plates well at such high pH (pH 11.5 or higher) and to eliminate stains during printing, sulfites are very effective, and anionic surfactants are also used. The agent is highly effective in accelerating the development of negative-working photosensitive lithographic printing plates.

Sulfites have the function of dissolving water-insoluble diazo resins in aqueous solutions, and are particularly effective in developing non-lithographic printing plates from photosensitive layers combined with hydrophobic resins, preventing stains even on plate materials that have been manufactured for a long time. You can make a printing board without any printing board. It also improves the developability especially when a negative photosensitive lithographic printing plate is developed at high pi. As the sulfite, alkali metal salts such as sodium, potassium, lithium, alkaline earth metal salts such as magnesium, or ammonium salts are useful.

The concentration of sulfite is preferably in the range of 0.1 to 10% by weight, particularly 0.2 to 5% by weight.

Examples of anionic surfactants include higher alcohols (C.I.
~02□) Sulfuric ester salts [e.g., sodium salt of lauryl alcohol sulfate, sodium salt of octyl alcohol sulfate, ammonium salt of lauryl alcohol sulfate, [T-Ball B-81J
(Product name: Shell Chemical), Sodium Furkyl Sulfate, etc.], Aliphatic alcohol phosphate ester salts (e.g., sodium salt of cetyl alcohol phosphate ester, etc.), Alkylaryl sulfonates! (e.g., sodium dodecylbenzenesulfonic acid, sodium salt of inpropylnaphthalenesulfonic acid, sodium salt of cina7talin disulfonic acid, sodium salt of metanitrobenzenesulfonic acid, etc.), sulfonic acid salts of alkylamides (e.g., C+ tH* zcONcHzcllzsOJ
a), dibasic CH.

There are sulfonic acid salts of fatty acid esters (eg, sodium sulfosuccinate octyl ester, sodium sulfosuccinate dihexyl ester, etc.). Among these, alkylnaphthalene sulfonates are particularly preferably used.

The concentration of anionic surfactant is preferably in the range of 0.2 to 10% by weight, particularly 1 to 5% by weight.

Examples of alkaline agents used in the developer of the present invention include sodium silicate, potassium silicate, sodium hydroxide, lithium hydroxide, tribasic sodium phosphate, dibasic sodium phosphate,
Inorganic alkaline agents, such as tribasic potassium phosphate, dibasic potassium phosphate, tribasic ammonium phosphate, heptadmonium diphosphate, sodium metasilicate, sodium bicarbonate, sodium carbonate, potassium carbonate, ammonium carbonate, etc. Organic alkaline agents such as triethanolamine and tetraalkylammonium hydroxide and ammonium 191t acids are useful. Among these, alkali silicate is most preferable because it has good development stability. The content of the alkaline agent in the developer composition is 0.05~
It is suitable to use it in a range of 20% by weight, more preferably from 0.1 to 10% by weight.

The most preferred embodiment of the present invention is that the developer satisfies the conditions regarding the nonionic surfactant and pH, and further includes a silicate as an alkaline agent and an organic solvent having a solubility in water of 10% by weight or less at 20°C. , a sulfite, and an anionic surfactant. With this embodiment, a wide variety of photosensitive lithographic printing plates having widely different developability can be developed better and more quickly with one developer.

The following additives can be added to the developer according to the present invention in order to further improve development performance.

For example, NaC (!
, KCZ, KBr and other neutral salts, JP-A-58-19095
EDT^ described in No. 2, chelate cutting of NT 8, etc., JP-A-1989-5
(Co(Nl(3)s)C described in No. 9-121336
1, etc., sodium flukylnaphthalene sulfonate described in JP-A-50-51324, anionic or amphoteric surfactants such as N-tetradecyl-N r N-dihydroxyethylbetaine, and JP-A-56-142528. ampholytic polymer electrolytes such as a copolymer of vinylbenzyltrimethylammonium chloride and tetrawham acrylate, reducing inorganic salts described in JP-A-57-192952, non-fi such as lithium chloride described in JP-A-58-59444; +7 tium compounds, organic lithium compounds such as lithium benzoate described in Japanese Patent Publication No. 50-34442, organic gold I containing Si, Ti, etc. described in Japanese Patent Publication No. 59-75255
Examples include fG surfactants and organic boron compounds described in JP-A-59-84241.

The image forming layer of the photosensitive lithographic printing plate according to the present invention contains a photosensitive substance as an essential component, and the physical and chemical properties of the photosensitive substance change upon exposure or subsequent development treatment. For example, there is a difference in solubility in a developer due to exposure, a difference in intermolecular adhesion between before and after exposure, a difference in affinity for water and oil due to exposure or subsequent development, and A device that can form an image area using a photographic method, and
A multilayer structure described in Japanese Patent No. 5-166645 can be used.

Typical photosensitive substances include, for example, photosensitive diazo compounds, photosensitive at compounds, compounds with ethylenically unsaturated double bonds, epoxy compounds that polymerize with acid catalysts, and C-0- that decomposes with acids. Examples include compounds having a C-group, silyl ethers, and silyl esters. Typical Bon-type compounds that become alkali-soluble upon exposure to light include 0-quinonenoacite compounds, acid-decomposable nityl compounds, and ester compounds. Aromatic diazonium salts are examples of negative-type compounds whose solubility decreases upon exposure to light.

Specific examples of 0-quinonenoasite compounds include, for example, Japanese Patent Application Publication Nos. 47-5303, 48-63802, and 48
-63803, 49-38701, 56-10
No. 44, No. 56-1045, Special Publication No. 41-11222
No. 43-28403, 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, German Patent No. 1,330,932, German Patent No. 854゜890, Japanese Unexamined Patent Publication No. 60-37549, German Patent No. 854.
0-10247, No. 60-3625, etc., and the present invention is preferably applied at least to photosensitive lithographic printing plates using these compounds alone or in combination as photosensitive components. I can do it.

These photosensitive components include 0-quinonediazide sulfonic acid esters of aromatic hydroxy compounds or.

- Includes quinonediazide sulfonic acid or 0-quinonediazidecarboxylic acid amide of aromatic amino compounds, as well as those using these 0-quinonediat compounds alone, and alkali-soluble resins. This includes those in which the mixture is mixed with the photosensitive layer and this mixture is provided as a photosensitive layer.

Alkali-soluble resins include /borac type 7ヱ/-l resins, and specifically, phenol formaldehyde resin, cresol formaldehyde resin, 7ケ/-l cresol mixed formaldehyde I (111t), cresol xylenol mixed formaldehyde resin, etc. Furthermore, as described in JP-A-50-125806, L-butylphenol formaldehyde (such as a fat with a carbon number of 3
A combination of 7er7-yl 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 the 0-quinonediat compound as a photosensitive component.

The present invention is applicable to the amount per unit area of the photosensitive layer containing the 0-quinonediat compound as a photosensitive component, preferably in the range of about 0.5 to 72/&2.

The image exposure of the positive photosensitive lithographic printing plate to which the method of the present invention is applied does not need to be particularly changed and may be carried out in accordance with a conventional method.

A typical photosensitive component of the negative photosensitive layer is a diazo compound, such as a diazo resin which is a condensate of diazonium salt and/or p-diazophenylamine and formaldehyde, as described in Japanese Patent Publication No. 7364/1983. Copolycondensation of 3-methoxydiphenylamine-4-noazonium chloride, 4-nitrodiphenylamine, and formaldehyde, which are described in Japanese Patent Publication No. 49-48001, such as phenol salt or fluorocaprate of p-diazophenylamine. 2-methoxy-4-hydroxy-5-benzoylbenzene sulfonate of a condensate of p-diazophenylamine and formaldehyde, condensation of p-diazophenylamine and formaldehyde Examples include tetrafluoroborate, hexafluorophosphate, and the like. The present invention can be preferably applied at least to negative photosensitive planographic printing 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. Such resins include shellac, polyvinyl alcohol derivatives, and S described in JP-A-50-118802.
Copolymers frequently containing alcoholic hydroxyl groups, JP-A-1983-1987
A copolymer having a phenolic hydroxyl group in a side chain as described in No. 155355 may be mentioned.

These 4II III] include copolymers containing at least 50% by weight of structural units represented by the following general formula,
R1 ÷ CH2-C+ COO(CH2CHO) n H (wherein, R6 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 from 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 photosensitive lithographic printing plate to which the developer and developing method of the present invention are applied may further contain additives such as dyes, plasticizers, and components that provide printout performance. The amount per unit area of is at least 0.1 to 7
The present invention can be applied to a frame of 1F/31'' 6. Supports used in the photosensitive lithographic printing plate include paper,
Plastics (e.g. polyethylene, polypropylene,
(polystyrene, etc.) laminated paper, plates of metals such as aluminum (including aluminum alloys), zinc, copper, etc., cellulose diacetate, cellulose triacetate, cellulose propionate, polyethylene teretalate, polyethylene, polypropylene, polycarbonate, polyvinyl acetal Examples include plastic films such as, paper or plastic films laminated or vapor-deposited with metals such as those mentioned above, steel plates plated with aluminum or chrome, and among these, aluminum and aluminum-coated composite supports are particularly suitable. is preferred.

Further, the surface of the aluminum material is preferably roughened for the purpose of increasing water retention and improving adhesion to the photosensitive layer.

Examples of surface roughening methods 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 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. M8I is 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.

Furthermore, if necessary, a sealing treatment and other surface treatments such as immersion in a regulated potassium zirconate aqueous solution can be performed.

In addition, the development method using the developer according to the present invention includes, in addition to the development process, if necessary, after the development process, a development stop process (the stop process solution includes a disposable method or a recycle method), an insensitive resin. Each individual treatment step of the chemical treatment step, a development stop treatment step followed by a desensitization treatment step, a treatment step that combines a development treatment step and a desensitization treatment, or a development stop treatment step and a desensitization treatment step. For example, a combination of the processing steps disclosed in Japanese Patent Application Laid-Open No. 54-8001 may be included.

In addition, when developing the negative type and positive type photosensitive lithographic printing plates in the present invention with the same developer, conditions other than the developer composition (e.g., development temperature, development time, etc.) are different between the negative type and positive type. Changing it is optional.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to specific examples, but the present invention is not limited thereto.

Examples 1-7, Comparative Examples 1-2 20% phosphoric acid on an aluminum plate with a thickness of 0.24zz)
After degreasing by immersing in a lithium aqueous solution and electrolytically polishing it in a 0.2N hydrochloric acid bath at a current density of 3^/, w2,
Anodized in a sulfuric acid bath. At this time, the amount of anodization was 4g/
It was x2. Further, the aluminum plate was sealed with an aqueous sodium metasilicate solution to prepare an aluminum plate for use in a lithographic printing plate.

Next, the following photosensitive liquid crystal was coated on this aluminum base to obtain a negative photosensitive lithographic printing plate, and photosensitive liquid B was coated to obtain a positive photosensitive lithographic printing plate. Coating was performed using a spin coater and dried at 100° C. for 4 minutes.

The coating film thickness weight was 2.5 g/x2 for both plates.

(Photosensitive liquid crystal) ・N-(4-hydroxyphenyl) methacrylamide:
Copolymer of 7 Acrylonitrile: Ethyl acrylate: Methacrylic acid = 27:33:41:6 (weight ratio) Acid value: 80) 5.0 g/P-7 Zono phenylamine para Hexafluorophosphate of formaldehyde condensate
...0. sy Julimar AC-1OL (trade name, manufactured by Nippon Pure Chemical Industries, Ltd., acrylic acid polymer) ・・・0.05g ・Tartaric acid ・・・0.05° ・Victoria Purepur-BOH ( Product name, manufactured by Odugaya Chemical Industry Co., Ltd., dye)...
...0.1g - Novolac resin (pp-:3121) (manufactured by Gunei Chemical Co., Ltd.) ...0.15g - Bluronic Shi-64 (product name, manufactured by Asahi Denka Co., Ltd., surface active agent)...
0,005g ・Methyl cellosolve ・・・・・・100z1
(Photosensitive liquid B) ・S7toquinone-(1,2)-noanod-(2)-5-
X/l, fused product of phonic acid chloride and resorcinol-benzaldehyde resin...3.5g ・...-cresol-formaldehyde/borac resin"
M P-707” (manufactured by Gunei Chemical Industry Co., Ltd.)...
・・9g ・Su7toquinone-(1,2)-noacyto-(2)-4-
Sulfonic acid chloride・・・0.159・Victoria Pure Blue BOH (Product name, manufactured by Hodogaya Chemical Industry Co., Ltd., dye)・・・・
0.2 g Methyl cellosolve 100 g The plate thus obtained was exposed to light using a 2 Kw metal halide lamp through a step wedge with a density difference of 0.15. Thereafter, using the developing solution shown in Table 1, development was carried out in an automatic processor at 25°C for various developing times.
2 results were obtained.

In addition, the pl+ of the developer is determined by the use surface iI after adding the additive.
The solution was adjusted with 10% NaOII or 1N-11CN.

22-2 and Table 3 below, the N plate represents a negative photosensitive lithographic printing plate, the P plate represents a positive photosensitive lithographic printing plate, and the gradation properties are developed using developing ink 5PO-1 (Konishiroku Photo Industry Co., Ltd.). These are the results of an evaluation using a product manufactured by Co., Ltd.

As can be seen from Table 2, the developers of Examples 1 to 7 have a wider development latitude than the developers of Comparative Examples 1 and 2, and are effective for positive planographic printing plates. The gradation property was 113N hard (the difference between the number of one step of peta and the number of one step of clear was small), and it showed excellent developing performance. Furthermore, among the developing solutions of Examples 1 to 7, those using a quaternary ammonium salt type cationic surfactant have better development latitude and gradation than those using an amine type cationic surfactant. showed his sexuality.

Example 8 Ethylene glycol monomethyl ether 3 under nitrogen flow
150 parts by weight of 2-hydroxyethyl methacrylate, 90 parts by weight of acrylonitrile, 79.5 parts by weight of methyl methacrylate, 10.5 parts by weight of methacrylic acid, and benzoyl peroxide. 1
．． 2 parts by weight of the mixed solution was added dropwise over 2 hours.

15 minutes after the completion of the dropwise addition, 300 parts by weight of ethylene glycol more methyl ether and 0.3 parts by weight of benzoyl peroxide were added, and the mixture was allowed to react for 4 hours. After the reaction was completed, the copolymer was diluted with methanol and poured into water to precipitate it at 70°C.
It was dried in vacuum.

This 2-hydroxyethyl methacrylate copolymer (1
) had an acid value of 21.

A 23 aluminum plate with a thickness of 0.1511 was degreased by immersing it in a 10% aqueous solution of tertiary sodium phosphate maintained at 80'C for 3 minutes, then grained with a nylon brush, and then heated to 60'C.
It was desmutted with a 3% aqueous solution of sodium aluminate.

The aluminum plate was anodized in 20% sulfuric acid at a current density of 2^/dz2 for 2 minutes and then treated with a 25% aqueous solution of sodium silicate at 70'C for 1 minute.

This aluminum plate was coated with Niggi's photosensitive liquid and heated to 100°C.
The mixture was dried for 2 minutes to obtain a negative-type photosensitive lithographic printing plate.

・2-hydroxyethyl methacrylate copolymer (1)
...87 parts by weight 2-methoxy-4-hydroxy-5-benzoylbenzenesulfonate of condensate of p-noazodiphenylamine and paraformaldehyde ...10
Parts by weight: Oil Blue #603 (manufactured by Orient Chemical Industry Co., Ltd., triphenylmethane oil-soluble dye) 3 parts by weight 2-methoxyethanol 600 parts by weight Methanol ...600m fi
1-ethylene cyclolide 6001
i ft part dry coating weight is 2. It was jin/, 2. A negative original image containing a step film and halftone dots was brought into close contact with this photosensitive lithographic printing plate, and image exposure was carried out for 40 seconds from a distance of 70 cm using a 30 ampere carbon arc lamp.

On the other hand, as a Bono-type photosensitive lithographic printing plate, U.S. Patent No. 3.63
Polyhydroxyphenyl 7-toquinone-1,2-noanodo-5- obtained by condensation polymerization of acetone and pyrogallol as described in Example 1 of No. 5,709
Produced by dissolving 1 part by weight of sulfonic acid ester, 2 parts by weight of 7-borac type cresol formaldehyde resin, and 0.03 parts by weight of Oil Pull #603 in 20 parts by weight of 2-methoxyethyl acetate and 20 parts by weight of methyl ethyl ketone. The photosensitive solution was applied to a grained and anodized aluminum plate and dried at 80°C for 2 minutes to give a dry coating weight of 2.5y.
A photosensitive lithographic printing plate of /z2 was obtained. A transparent positive original image containing a step, wedge and halftone dots was brought into close contact with this photosensitive lithographic printing plate and imagewise exposed for 60 seconds from a distance of 70 cm using a 30 ampere carbon arc lamp.

As mentioned above, the exposed negative type and Bong type photosensitive lithographic printing plates were automatically developed using the following developer [^].
860 (manufactured by Konishiroku Photo Industry Co., Ltd.) was used for development. The results are shown in Table-3.

Development was performed at four points: 25°C and 30°C for 30 seconds, and 27°C for 20 seconds and 40 seconds, respectively. In addition, the pl of the developer
+ was adjusted to 12.60 g9 with NaOII at the time of use.

Developer [^,] - Sodium silicate 250g (Japanese Industrial Standards Silicate So No. 73) - Sodium hydroxide 30g - Ethyleneglyfur monophenyl ether 00g - Perex NB-L (Anionic surfactant manufactured by Kako Atlas Co., Ltd.) agent) 1.7
14y ・Sodium sulfite 200g ・Sanisol C (cationic surfactant manufactured by Kako Atlas Co., Ltd., dotecylbenyl methyl ammonium chloride) oy ・Tulfite (3-methyl-methoxybutal 7-ol) 200° ・Water 1:1 As a comparative developer, a developer [8] obtained by removing the cationic surfactant "Sanisol CJ" from the above developer [^]
was prepared. The developer (11) also has a pu of 12.5 when used.
Adjusted to 0.

As is clear from Table 3 below, the developer of the present invention [^]
The far point of development is between 30 seconds at 25"C and 20 seconds at 27°C, and even if the development becomes slightly excessive due to an increase in time and temperature from this development condition, there is no major change in the development result, and the halftone dot of 150 lines/ink is an excellent developer with good reproducibility and a wide development latitude.On the other hand, a comparative developer CB) obtained by removing the cationic surfactant from the developer [Δ] was similarly developed at 25°C for 30 seconds and at 27°C. 20 seconds is the far point of development,
Even at the far point of development, the image of the positive planographic printing plate was unfavorable due to its soft tone (the difference between the number of clear and solid steps was large). Furthermore, when the temperature of the developer becomes a little high or the development time becomes too long and the development becomes excessive, the performance deterioration increases (the image tends to become softer, and 3% of the halftone image The small dots of 5% and 5% became thinner or disappeared, making it impossible to obtain sufficient performance.

In addition, for negative planographic printing plates, the developer of the present invention [^] was superior to the comparative developer [8] in development latitude, albeit slightly.

〔Effect of the invention〕

According to the present invention, when a negative-working photosensitive lithographic printing plate and a positive-working photosensitive lithographic printing plate are developed with one developer (for example, when developing a negative-working photosensitive lithographic printing plate and a positive-working photosensitive lithographic printing plate with the same developer, When lithographic printing plates are developed indiscriminately), the developability, printing performance and development speed are improved.

Normally, rapid development can be achieved by making the developer thicker, increasing the processing temperature, or adding additives such as organic solvents that have a development accelerating effect, but no matter which method is used, the development Conventionally, it has been difficult to obtain a stable and good II image due to the narrow latitude. However, in the present invention, even if development is performed at about twice the speed of the conventional method, stable and good images can be obtained.

Note that if an organic solvent with a solubility in water of 10% by weight or less at 20°C is used in the developer, the image area will often be attacked during the development of a normal positive-working photosensitive lithographic printing plate, and even a slight amount of overdevelopment will cause damage to the image area. However, according to the present invention, by adding the above-mentioned cationic surfactant, good common development can be achieved even in the presence of the above-mentioned organic solvents. It becomes possible.

Claims (10)

[Claims] (1) In a method in which a negative photosensitive lithographic printing plate having an image forming layer on a support and a positive photosensitive lithographic printing plate having an image forming layer on a support are commonly processed using an aqueous alkaline developer, the developer is A developer for a photosensitive lithographic printing plate, which contains an activator in a range of 0.001 to 10% by weight and has a pH in a range of 11.5 to 13.5. (2) The developer according to claim 1, which contains 0.1 to 10% by weight of an organic solvent having a solubility in water of 10% by weight or less at 20°C. (3) The developer according to claim 1 or 2, which contains a sulfite. (4) The developer according to claim 1, 2, or 3, which contains an anionic surfactant. (5) Claim 1, 2, 3, or 4, characterized in that the cationic surfactant is a surfactant having a water-soluble quaternary ammonium salt structure. developer solution. (6) In a method in which a negative photosensitive lithographic printing plate having an image forming layer on a support and a positive photosensitive lithographic printing plate having an image forming layer on a support are commonly processed using an aqueous alkaline developer, the developer is A method for developing a photosensitive lithographic printing plate, comprising 0.001 to 10% by weight of an activator and a pH in the range of 11.5 to 13.5. (7) The developing method according to claim 6, wherein the developer contains 0.1 to 10% by weight of an organic solvent having a solubility in water of 10% by weight or less at 20°C. (8) The developing method according to claim 6 or 7, wherein the developer contains a sulfite. (9) The developing method according to claim 6, 7, or 8, wherein the developer contains an anionic surfactant. (10) Claims 6, 7, 8, or 9, characterized in that the cationic surfactant is a water-soluble surfactant having a quaternary ammonium salt structure. development method.