JPS63109443A - Developing process method for photosensitive lithographic printing plate improved in stability or the like of developing process - Google Patents

Abstract

PURPOSE:To obtain a finish or always stable and high quality by supplying a substantially unused aq. developing soln. onto a photosensitive lithographic printing plate to be processed and subjecting the plate to a developing process by a specific means for accelerating development and means for supplying the developing soln. CONSTITUTION:The photosensitive lithographic printing plate (PS plate) P which is fed to a developing section by a roller pair 1 is supplied with the developing soln. from a developing soln. onto the plate surface by a guide plate 4 an the plate surface is simultaneously rubbed by a rubbing member 6 provided with nylon brushes as the operation to accelerate the development, by which the material is developed. The developing soln. is kept stored in a developing soln. tank 7 and is fed by a pump 8. The member 6 is moved back and force by a driving source in the direction (arrow b direction) perpendicular to the progressing direction of the PS plate P. The used developing son. is collected by a receiving tray 10 and is discarded. The PS plate with which the development ends is transported by a transporting roller pair 2 to a rinsing section where the plate surface is rinsed by the water flow from a shower pipe 11 and thereafter, the PS plate is discharged by a transporting roller pair 3 to the outside of the machine. The rinsing water is kept stored in a rinsing tank 12 and is cyclically used by a pump 13.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for developing a photosensitive lithographic printing plate, and more specifically to a method for developing a photosensitive lithographic printing plate that has been improved so that stable development can be carried out at all times. Regarding processing method.

[Conventional technology]

When processing a large number of exposed photosensitive lithographic printing plates (hereinafter referred to as 25th plate), it is common to use an automatic developing machine, and the developing processing solution used at the same time has odor and environmental protection issues. Because of these reasons, developers that use water as the main solvent have become mainstream.

When processing the exposed 25th plate in an automatic developing machine, there are two methods: developing by spraying a developer while horizontally transporting the 25th plate, or placing the 25th plate in a developing tank containing a large amount of developer. A method is used in which the printing plate is immersed and developed while being conveyed in a curved manner. In all of these processing machines, it is necessary to prepare a large amount of developer to process one plate of 25 plates. In addition, in order to use the developer economically, it is recycled and reused, and in addition to the deterioration of the developer due to opening and processing, especially when the developer is alkaline, it is caused by the absorption of carbon dioxide from the air. Developer solution deterioration occurs, and the deteriorated developer solution often has to be replaced, making the management of the development work extremely troublesome.

In addition, in order to improve the above-mentioned drawbacks, there is a known method to keep the development process stable by replenishing the replenisher when processing the 25th plate with a large amount of circulating and reusing developer.
-144502, 55-115039, 58-
No. 95349, etc. Even in this replenishment method, although the frequency of liquid exchange is reduced, liquid exchange is still necessary, and problems of replenishment accuracy and replenishment fluctuations due to differences in the types of PS plates developed cannot be solved.

In addition, a replenishment device is required, and not only is the replenishment device itself expensive, but the replenishment device also requires $1 maintenance.

Further, a method for eliminating the troublesome replenishment method and saving developer is described in Japanese Patent Application Laid-open No. 32044/1983. This relates to a photographic processing device that is equipped with a developer diffusion plate close to the photosensitive material transfer path in an automatic processor, but a method for processing plate 25 with a small amount of developer using this device includes: It has the disadvantage that it is difficult to shorten the development time and cannot perform rapid processing.Also, since the 25 plate being conveyed is not necessarily horizontal but is slightly distorted up and down, the amount of developer tends to be uneven, resulting in uneven development. Easy,
There is a drawback that it takes time and effort to adjust the gap between the 25th plate to be processed and the developer diffusion plate.

[Problem that the invention seeks to solve]

The present invention aims to solve various problems related to the replenishment of developer solution, etc., and to provide a stable and economical method for developing photosensitive lithographic printing plates. An object of the present invention is to provide a 25-plate development method that can always maintain stable development using a developing solution. A second object is to provide a method for developing a photosensitive lithographic printing plate, which has improved workability and eliminates the need for developer management and solution exchange. A third object is to provide an inexpensive 25-plate development process that does not require a replenisher or developer replenisher. A fourth object is to provide a 25-plate development method that can always produce a uniform finish even when using a small amount of developer.

[Means for solving problems]

The above purpose is to automatically transport the 25 plates using an automatic developing machine, supply a developer containing substantially unused water as the main solvent to the surface of each PS plate to be processed, and develop the plate. In the development processing method in which development is performed by adding an accelerating operation, the development accelerating operation is an operation of rubbing the 25th plate with a rubbing member capable of rubbing the entire surface in a direction orthogonal to the conveying direction, and the This is achieved by a 25-plate development processing method characterized in that unused developer is supplied within the plane in which the rubbing member moves.

The above-mentioned substantially unused developer means a developer that has the same developing ability as an unused developer, and does not reduce the developing ability of an unused developer, in addition to a completely unused developer. It is also possible to use a mixture of used developer solutions within a certain range. For example, during development, a used developer solution can be supplied from a part of the developer supply means to the plate surface along with an unused solution. However, it is most preferable to use the entire amount of unused liquid.

A direction perpendicular to the conveying direction used in the present invention (hereinafter referred to as 1
For the rubbing operation using a rubbing member that can rub the entire surface (abbreviated as 1-hand direction), a method of rubbing by rotation using a roller-shaped rubbing member whose length in the mid-hand force direction of the 25th plate to be processed is greater than that of the 25th plate being processed. , a method of rubbing by moving a flat rubbing member back and forth or left and right, or by rotating it. Among these, a method in which the rubbing operation is performed by reciprocating or rotating motion in only one direction is particularly preferable, such as a method of rotating the roller-shaped rubbing member described above, or a method of rotating a flat-shaped rubbing member that is longer than the length in the 11-hand direction of the 13th plate to be processed. Particularly preferred is a method in which the object is moved back and forth or left and right.

Note that a plurality of these rubbing members may be used in combination.

These rubbing members can be made using, for example, a brush, a cloth, or a cloth, but a brush is particularly preferable, and the material thereof is preferably nylon.

In the present invention, it is necessary to supply the developer within the plane in which the rubbing member moves. Methods for supplying the developer include spraying from a tube with multiple narrow openings, supplying from the gap between two plate-like objects, using a roll with a rough surface, or using a plate-like member. It includes the method of supplying, etc.
In these methods, the position where the developer is supplied to the plate surface may be on the surface where the rubbing member moves, and the developer supply system and the rubbing member may be separated or integrated. However, especially in the present invention, it is preferable that the brush be integrated.1 For example, a flat brush having a developer supply port in the gap between the brushes, and a roller brush having a developer supply port in the gap between the brushes. Particularly preferred.

Further, as the developer supply method, only one method may be used, or two or more methods may be used in combination.

The amount of developer supplied by these methods is 18 plates 1
It can be determined based on various criteria, such as a fixed amount per sheet, an amount proportional to the area of the PS plate, or an amount proportional to the length or width of the PS plate to be processed. This can also be changed depending on the area of the non-image portion of the image to be formed. The number may be selected as appropriate depending on the structure of the automatic processor, the size of the PS plate to be processed, the properties of the PS plate and developer, etc., but it is preferably 11 or less per plate.

In addition, the developer supply section has a control mechanism that is linked to a detection mechanism such as a sensor that detects the presence or absence of a PS plate, and a stop fi14 is activated before the PS plate is carried into the development section and after passing through. It is desirable that the

Also, the temperature of the developer during use is generally 5℃ to 60℃.
, preferably 10°C to 45°C, more preferably 25°C
The temperature ranges from 35°C to 35°C.

The developing solution can be stored in a storage tank after it has been finished as a working solution and supplied onto the 25th plate during processing, or it can be stored separately as a stock solution, a diluted solution, or multiple solutions with different combinations. The liquids may be stored in a tank and supplied onto the printing plate, or may be automatically mixed at the time of supply to finish the liquid as a working liquid, or may be automatically mixed and supplied to the printing plate in a uniform state.

In addition to the above-mentioned development process, the automatic developing machine used to carry out the method of the present invention may also carry out, if necessary, a development stop process after the development process (including a method in which the stop process solution is disposable or cyclically used), Each individual treatment step of the desensitization treatment step,
The process may include a development stop treatment step followed by a desensitization treatment step, or a treatment step in which the development stop treatment step and the desensitization treatment step are performed simultaneously, for example, as described in JP-A-54-8002. Further, each of the development processing step and the other steps may be plural. For example, the development processing step may be divided into a first development processing step and an I/1iS2 development processing step. In addition, the unnecessary liquid used in the above-mentioned development process and post-development process is treated as waste liquid, but it is sometimes desirable to store it in a waste liquid tank or the like. .

The PS plate used in the method of the present invention is one that is developed with a developer containing water as the main fB medium, and has a photosensitive layer whose solubility changes upon light irradiation coated on a support. Alternatively, a soluble layer on which an image-like resist layer can be formed by electrophotography or the like is provided on the support.

Supports used for the PS plate include paper, plastic (e.g. polyethylene, polypropylene, polystyrene, etc.) laminated paper, aluminum (including aluminum alloys), zinc, metal plates such as Tsuba, cellulose diacetate, etc. , plastic films such as 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 these, aluminum and aluminum-coated composite supports are particularly 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 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. A liquid is preferable, and the aluminum plate subjected to the surface roughening treatment is desmutted with an acid or alkali aqueous solution as 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 potassium fluorozirconate aqueous solution can be performed.

The 28th edition photosensitive composition used in 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 can be used.

Typical photosensitive substances include, for example, photosensitive diazo compounds, photosensitive azide compounds, compounds with ethylenically unsaturated double bonds, Epoquin compounds that polymerize with acid catalysts, silyl ether polymers that decompose with acids, etc. C-0-
Examples include a combination of a compound having a C-group and an acid generator. Examples of the photosensitive diazo compound include an O-quinone diacid compound as a bot-type compound, and an aromatic diazonium salt as a negative-type compound. Examples of substrates for 0-quinonediaside compounds include, for example, Japanese Patent Application Laid-Open No. 47-5303
No. 48-63802, No. 48-63803, No. 49-38701, No. 56-1044, No. 56-1
No. 045, Special Publication No. 41-11222, No. 43-284
No. 03, No. 45-9610, No. 49-17481,
U.S. Patent No. 2,797,213, U.S. Patent No. 3,048,1
No. 20, No. 3 188.210, No. 3,454,
No. 400, No. 3,544,323, No. 3,573
, No. 917, No. f53,674,495, No. 3,7
85°825, British Patent No. 1,227,602, British Patent No. 1,251,345, British Patent No. 1,267.005,
fjS1,329,888, fjS1.330,93
No. 2, German Patent Nos. fjS854 and 890, etc., and the present invention can be preferably applied at least to the 28th plate in which these compounds are used alone or in combination as photosensitive components. . These photosensitive components contain 0-
Included are quinonediazide sulfonic acid esters or 0-quinonenoasidecarboxylic acid esters and aromatic amino/compounds such as 0-quinonediazide sulfonic acid or 0-quinonediazidecarboxylic acid amide; It includes those used alone and those mixed with an alkaline resin and provided with this mixture as a photosensitive layer. Alkali-soluble resins include novolak-type phenolic resins, specifically 7-enol formaldehyde resins, cresol formaldehyde resins,
Includes phenol-cresol mixed formaldehyde resin, cresol xylenol mixed formaldehyde 84 resin, etc. Furthermore, as described in JP-A-50-125806, in addition to the above-mentioned phenolic resin, t-
A combination of a phenol substituted with an alkyl group having 3 to 8 carbon atoms or a condensate of cresol and formaldehyde, such as butyl 7-ethyl formaldehyde resin, is also applicable. If necessary, additives such as dyes, plasticizers, and components imparting printout performance can be added to the photosensitive layer containing the 0-quinonediazide compound as a photosensitive component.

The present invention can be applied to an amount per unit area of a photosensitive layer containing an 0-quinone noasite compound as a photosensitive component, preferably in the range of about 0.5 to 7 g/I62.

There is no particular need to change the image exposure of the positive type 28 plate to which the method of the present invention is applied, and a conventional method may be used.

A typical photosensitive component of the negative photosensitive layer is a diazo compound, such as a diazo resin which is a condensate of noazonium salt and/or p-diazophenylamine and formaldehyde, as described in Japanese Patent Publication No. 7364/1983. 3-notoxynophenylamine-4-noazonium chloride and 4-nitronobenylamine described in Japanese Patent Publication No. 49-48001, such as phenol salt or fluorocaprate of p-noazinophenylamine Noazo If fat consisting of an organic solvent soluble salt of a copolycondensate of p~diazonophenylamine and formaldehyde, 2-methoxy-4-hydroxy-5-benzoylbenzene sulfonate of a copolycondensate of p~diazonophenylamine and formaldehyde , tetrafluoroborate, hexafluorophosphate, etc. of a condensate of ρ-7zonophenylamine and formaldehyde. The present invention can be preferably applied at least to negative PS 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 copolymers having an alcoholic hydroxyl group in the side chain described in JP-A-50-118802, as well as derivatives of polyvinyl alcohol, JP-A-50-118802, etc.
Examples include copolymers having phenolic hydroxyl groups in their side chains, as described in No. 5-155355.

These resins include copolymers containing at least 50% by weight of structural units represented by the following general formula; ethyl group or chloromethyl group, n is an integer of 1 to 10) and 1 to 80 mol% of monomer units having an aromatic hydroxyl group, and acrylic ester and/or methacrylic ester monomer. Included are polymer compounds having 5 to 90 mol% of somatic units and an acid value of 10 to 200.

Additives such as dyes, plasticizers, and components that degrade printout performance can be added to the photosensitive layer of the negative PS plate to which the development method of the present invention is applied.

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 112 g/l.

There is no particular need to change the image exposure of the negative PS plate to be developed using the development processing method of the present invention, and conventional methods can be followed. However, it is particularly useful when the developer is alkaline.

Among alkaline developers, those containing water as a solvent and an alkali agent, an organic solvent, an anionic surfactant, a sulfite, etc. are preferable for negative-tone PS plates that use a diazo compound or the like as a photosensitive substance. 6 The alkaline agents used include sodium silicate, potassium silicate, sodium hydroxide, lithium hydroxide, sodium triphosphate, sodium diphosphate, potassium triphosphate, potassium diphosphate, and triphosphate. Inorganic alkaline agents such as ammonium, ammonium diphosphate, sodium metasilicate, sodium bicarbonate, sodium carbonate, potassium carbonate, ammonium carbonate, etc., organic alkalis such as mono-, triethanolamine and tetraalkylammonium hydroxide. and ammonium silicate are useful. The content of alkaline agent in the developer composition is 0.
．． It is suitable to use it in the range of 0.05 to 20% by weight, more preferably 0.1 to 10% by weight.

As the WI solvent, ethylene glycol monophenyl ether, benzyl alcohol, 11-propyl alcohol, etc. are useful. The content of the organic solvent in the developer composition is preferably kept at about 0.5 to 15% by weight, and more preferably from 1 to 5% by weight.

As anionic surfactants, higher alcohols (C,
~02□) Sulfuric acid ester salts [e.g., sodium salt of lauryl alcohol sulfate, sodium salt of octyl alcohol sulfate, ammonium salt of latulyl alcohol sulfate, [T-Ball B-81
J (trade name, manufactured by Shell Chemical Co., Ltd.), secondary sodium alkyl sulfate, etc.] aliphatic alcohol phosphate ester salt M (e.g., sodium salt of cetyl alcohol phosphate ester, etc.), alkylaryl sulfonate 'B (e.g., dodecylbenzene) Sodium salt of sulfonic acid, sodium salt of inpropylnaphthalene sulfonic acid, Nona 7
Sodium salt of taledisulfonic acid, sodium salt of metanitrobenzenesulfonic acid), sulfonate salts of alkylamides (e.g. C, H3) CONCHzCH
2SO, Na, etc.), dioctyl thorium sulfosuccinate, dioctyl sulfosuccinate, nohexyl sodium sulfosuccinate, etc.). Among these, sulfonate salts are most preferably used.

Sulfite has the function of dissolving water-insoluble diazo resin in an aqueous solution, and is particularly useful in developing PS plates consisting of a photosensitive layer combined with a hydrophobic resin.
Even printing plates can be made without stains. Useful sulfites include alkali metal salts such as sodium, potassium, and lithium, and alkaline earth metal salts such as magnesium.

On the other hand, for positive photosensitive materials having a photosensitive layer containing an 0-quinonediaside compound or the like, the alkali agent is usually added at a concentration of 0.
An aqueous solution containing 1 to 3011% by weight, preferably 0.5 to 20% by weight, is used, and it is usually preferable to use it in the range of 119 to 14.

The following additives can be added to such a developer in order to further improve the developing performance.

For example, NaC4' described in JP-A-58-75152,
Neutral salts such as KCl and KBr, JP-A-58-19095
Chelating agents such as EDT^ and NT^ described in No. 2, JP-A No. 5
[CO (formerly 1s)s) C described in No. 9-121336
1s, complexes such as COCl2.611.0, JP-A-1987-
Anionic or amphoteric surfactants such as sodium flukylnaphthalene sulfonate, N-tetradecyl-N, N-7 hydroxyethyl betaine described in US Pat. No. 51324; Ionic surfactant, JP-A-55-959
cationic polymers such as the methyl chloride quaternary product of p-zomethylaminomethylboristyrene described in No. 46;
Ampholytic polymer electrolyte such as a copolymer of vinylbenzyltrimethylammonium chloride and sodium acrylate described in JP-A-56-142528, JP-A-57-192
Reducing inorganic salts such as sulfite described in No. 952) +7um, inorganic lithium compounds such as lithium chloride described in JP-A-58-59444, organic lithium compounds such as lithium benzoate described in JP-A-58-34442 , Japanese Patent Publication No. 1983-
Organometallic surfactants containing 5iSTi etc. described in No. 75255, organoboron compounds described in vfrJIY No. 59-84241, 4a7 ammonium salts such as tetraalkylammonium oxides described in European Patent No. 1 oioto, benzyl alcohol, ethylene glycol monophenyl Examples include organic solvents such as ether 7't1.

〔Example〕

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 An aluminum plate with a thickness of 0.31III was electrochemically roughened in a nitric acid solution, thoroughly washed, and then anodized in a sulfuric acid solution to form an oxide film of 2.5 g/n2 on the aluminum plate. formed on the surface.

After washing with water and drying, 3 parts by weight of the esterified product of resorcin benzaldehyde resin synthesized according to the example of JP-A No. 56-1044 and 7-1,2-no-7-5-sulfonyl chloride, and cresol formalin. 9 parts by weight novolac resin and Victoria Pure Blue BO
A photosensitive solution prepared by dissolving 0.12 parts by weight of H (manufactured by Hodogaya Chemical Industry Co., Ltd.) in 100 parts of 2-methoxyethanol was applied onto the above support and dried to form a photosensitive layer of approximately 2.8 g/m2. A PS version was obtained.

The Bot type 28 plate obtained in this way is 800III.
A large number of sheets were prepared by cutting them to a size of IIX 1003 mm.

Next, a 80C-NOH was applied to this sample through a transparency having a uniform dot image over the entire surface with a dot image area ratio of about 8096.
Exposure was applied from a distance for 60 seconds using a 2KW metal halide lamp. The exposed sample was developed using an automatic developing machine shown in FIG.

P in the figure is an exposed PS plate, and the PS plate has a transport roller pair 1.
2.3, it is transported in the direction of arrow a. roller vs 1
The PS plate sent to the developing section is placed on a guide plate 4, and a developer is supplied to the plate surface from a developer pipe 5, and at the same time, as a development promotion process, the layer surface is rubbed by a rubbing member 6 equipped with a nylon brush and developed. Ru. The developer is stored in the developer 1ff17 and is sent by the pump 8. The 11!9 member reciprocates in a direction perpendicular to the advancing direction of the PS board (also in the direction of the arrow) by a drive source not shown in the figure.

The effective width of the developing section, that is, the rubbing member of this machine was 100 mm. The used developer is collected and disposed of by a receiving tray 10.

After the development has been completed, the lithographic printing plate is transported to a washing section by a pair of transport rollers 2, and the plate surface is washed with water by a stream of water from a shower pipe 11, after which it is discharged out of the machine by a transport roller N3. The washing water is stored in a washing tank 12 and circulated by a pump 13.

A developer having the following composition is put into the developer tank 7, and the exposed 2
The third plate sample was developed by being fed so that the length in the transport direction was 1003II116.

Development a composition Sodium silicate water soluble 'a (SiOz/Na2O molar ratio 1.8, SiO□ content 37.5% by weight)
...2.9 parts by weight water
...17.1 parts by weight When the obtained plate was printed on an offset printing machine, good prints were obtained, especially the thin white spots in the shadow areas were very well removed (commonly referred to as having a good opening). VT signs with no gradation were observed.

Further, 100 PS plate samples were continuously processed, and the same printing was performed on the 100th plate, and as a result, a good printed matter was obtained, as was the case with the first plate.

Example 2 A grained aluminum plate with a thickness of 0.241 fim was anodized in sulfuric acid to form an oxide film of about 2 g/m2, washed thoroughly, then immersed in sodium silicate water: PI solution, and thoroughly washed with water. , dried, and coated with a photosensitive solution having the following composition.

Photosensitive liquid composition (molar ratio is 8.5:24:60.5 in the above order)
: 7) 5.0 parts by weight f1g Hexafluorophosphate of a condensate of p-diazodiphenylamine and paraformaldehyde 0.5 parts by weight Victoria Pure Blue BOH (Hodogaya Chemical Industry Co., Ltd.) 0.1 parts by weight Methyl cellosolve The coating amount after drying 100 parts by weight was 1.8y/m''.The negative PS plate thus obtained was 800mm x 1003
A large number of sheets cut into mm size were prepared.

The sample was then exposed through a transparent negative for 30 seconds from a distance of 50 cm using a 2 KW metal halide lamp. Next, using the same automatic developing machine shown in Figure 3, except that the scrubbing member was a rotating brush and a VI type with a developer supply port inside the roll, the following composition was added to the developer tank. Add a developer and heat the above-mentioned exposed and quenchable printing plate at 80 (hm
It was transported and developed at a speed of /akin. The amount of developer supplied was adjusted to 180x (l).

Developer composition Phenyl cellosolve 40ffi fl
10 parts by weight of sodium 11-butylnaphthalenesulfonate 12 parts by weight of sodium 11-butylnaphthalene sulfonate
Co., Ltd.) 0.05 parts by weight water
When the plate after washing with 937 parts by weight was printed on a printing machine, good printed matter was obtained.

After the second sheet, 100 sheets were processed using the same developing method.

When the 100th processed plate was printed on a printing press, a good printed matter similar to that of the first sheet was obtained, and the opening of the edge part was also very good.

Example 3 An experiment similar to Example 1 was conducted using the automatic developing machine shown in Fig. 5 and a developer having the following composition.
Good prints similar to those obtained were obtained.

Developer composition Potassium silicate (SiOz/20 molar ratio 1.2.5iO
z content 2% by weight) 100 parts by weight Sodium isopropylnaphthalene sulfonate 0.05
Parts by Weight [Effect of the Invention] The present invention provides a method for supplying substantially unused aqueous developer onto a photosensitive lithographic printing plate to be processed, and carrying out development processing using specific development accelerating means and developer supplying means. Therefore, compared to the conventional method of circulating and reusing the developer, it is possible to always obtain a stable and high-quality finish. Furthermore, there is no need to replace the liquid, and work efficiency is significantly improved. Further, it is possible to obtain a uniform finish and rapid development, which could not be achieved with the conventional processing method using a small amount of developer, and also to obtain high-quality halftone dots. In particular, compared to the conventional method of processing using a small amount of developer, in which the opening of the shadow area was poor, the present invention has the advantage that the opening of the shadow area is extremely good. Furthermore, in the present invention, it has become possible to easily and stably process negative and positive plates in common over a long period of time without replacing the developer in one developer tank.

[Brief explanation of the drawing]

Figures 1, 3, and fi5 are perspective views of the developing device used in the embodiment of the present invention, Figure Pt52 is of Figure 1, and Figure 4 is P1.
Fig. tJ3 and Fig. 6 are sectional views of Fig. fi5 as viewed from the middle direction of the rubbing member. 1.2, 3...Transport roller pair 5.5゛...Developer solution vibro, 6...Rubbing member 7...Developer tank a

Claims (2)

[Claims] (1) The photosensitive lithographic printing plate is automatically conveyed using an automatic developing machine, and the surface of each photosensitive lithographic printing plate is treated with a developer containing substantially unused water as the main solvent. In the development processing method in which the photosensitive planographic printing plate is supplied to the plate and developed by adding a development accelerating operation, the development accelerating operation is an operation in which the photosensitive planographic printing plate is rubbed with a rubbing member capable of rubbing the entire surface in a direction orthogonal to the conveyance direction. A method for developing a photosensitive lithographic printing plate, characterized in that the substantially unused developer is supplied within the plane in which the rubbing member moves. (2) Claim 1, characterized in that the method of rubbing the entire surface of the photosensitive lithographic printing plate in a direction orthogonal to the conveyance direction is a method of constant reciprocating or rotational movement in only one direction. A method for developing a photosensitive lithographic printing plate.