JPS63179358A - Method for processing photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To extent the processing liquid life of an aq. surfactant soln. by executing the processing by the aq. soln. contg. the surfactant in plural stages after a developing stage. CONSTITUTION:The processing stage by the aq. soln. contg. the surfactant is provided continuously with, for example, surfactant processing parts 20, 20'. Part of the processing liquid of another processing stage is intermittently or continuously replenished after the processing in the processing stage where a plate passes first. The unused processing liquid is preferably replenished to the processing liquid of the processing stage of the second half in this case. The processing liquid life of the aq. surfactant soln. is thus increased.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for processing a photosensitive lithographic printing plate, and more particularly, to a processing method for a photosensitive lithographic printing plate with an improved post-processing step after development. It is about the method.

(Prior art) Exposed photosensitive lithographic printing plate (hereinafter simply referred to as PS plate)
When processing a large number of sheets, it is common to use an automatic developing machine, but after development, washing with running water is performed using a large amount of washing liquid. In this case, increased costs due to the use of large amounts of water,
There were drawbacks such as environmental pollution caused by washing wastewater.

Therefore, in recent years, measures have been taken to reduce the amount of wastewater,
Many proposals have been made regarding treatment methods that cause less environmental pollution and pollution.

For example, a method using an aqueous surfactant solution and omitting the water washing step after development of a PS plate is disclosed in JP-A-54-8002 and JP-A-55-
No. 115045, and JP-A-57-1
No. 58643, No. 59-58431, and No. 59-5
No. 7242, etc., proposes a method of repeatedly using washing water, but although the problem of pollution has been improved in these cases, it is still not a sufficient countermeasure in terms of workability. For example, when using a surfactant, it is necessary to frequently replace it with a new solution, which is not easy to work with and is expensive.

(Problems to be Solved by the Invention) In order to solve the above-mentioned problems, the purpose of the present invention is to reduce the amount of waste water in the water washing process after developing the PS plate, and to prevent pollution and environmental pollution. The purpose is to provide a method with fewer problems. It is an object of the present invention to provide a processing method for fpJ2 that does not use water submersion or that can efficiently perform correction operations such as erasure and addition after washing with a small amount of washing water. A third objective is to provide a processing method that can increase the life of the processing solution of the surfactant aqueous solution and reduce plate making costs.

(Means for solving the problem) In a method in which an exposed photosensitive lithographic printing plate is automatically conveyed and developed using an automatic developing machine, treatment with an aqueous solution containing a surfactant after the development process is performed. It has been found that the present invention can be achieved by a method for processing a photosensitive lithographic printing plate that includes at least two steps.

The present invention will be explained in detail below.

The PS plates covered by the present invention are those in which a photosensitive layer whose solubility changes upon irradiation with light is coated on a support, or in which an image-like Lennost layer is formed using an electrophotographic method or the like. A soluble layer is provided on a support.

Supports used for the above PS plates include paper, plastics (e.g. polyethylene, polypropylene, polystyrene, etc.), laminated paper, aluminum (including aluminum alloys), metal plates such as zinc, copper, etc., and diacetic acid. 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, full minitum or chrome Examples include plated steel, and among these,
Aluminum and aluminum-coated composite supports are preferred.

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

As the surface roughening method, generally known brush 47F rubbing method,
Examples include methods such as pole polishing, electrolytic etching, chemical etching, liquid honing, sandblasting, etc., and combinations thereof, preferably brush polishing, electrolytic etching, chemical etching, and liquid honing. In particular, surface roughening methods involving the use of electrolytic etching are preferred.

Furthermore, the roughened aluminum plate is preferably desmutted with an acid or alkali aqueous solution and anodized, if necessary, and furthermore, if necessary, sealed. , and other surface treatments such as immersion in a potassium fluorinorphinate aqueous solution can be performed.

The photosensitive composition of the PS plate used in the present invention contains a photosensitive substance as an essential component, and the physical and chemical properties of the photosensitive substance do not change upon exposure or subsequent development treatment. For example, there are differences in solubility in developing solutions due to exposure, differences in intermolecular adhesive strength before and after exposure, differences in affinity for water and oil due to exposure or subsequent development, and A material that can form an image area by electrophotography can be used.

Typical photosensitive substances include, for example, photosensitive material No. 7.
Examples include a zo compound, a photosensitive at compound, a compound having an ethylenically unsaturated double bond, an epoxy compound that polymerizes with an acid catalyst, and a compound having a C-〇-C- group that decomposes with an acid.

Examples of the photosensitive noazo compound include an 0-quinone no7side compound, which is a bottom-type compound that changes to be alkali-soluble when exposed to light, and an aromatic noazonium salt, which is a negative-type compound whose solubility decreases when exposed to light.

The developer used in the present invention is preferably an aqueous alkaline developer, and the alkaline agents used in the developer include sodium silicate, potassium silicate, sodium hydroxide, lithium hydroxide, tribasic sodium phosphate, Sodium phosphate, potassium triphosphate, potassium diphosphate, ammonium triphosphate, diammonium phosphate, sodium metasilicate, sodium bicarbonate, sodium carbonate, potassium carbonate, ammonium carbonate, etc. Inorganic alkaline agents such as mono-, triethanolamine, and organic alkaline agents such as tetraalkylammonium hydroxide and ammonium silicate are useful.

The content of alkaline agent in the developer composition is 0.05
It is suitable to use in the range of ~30 weight percent,
More preferably, it is 0.1 to 20 weight percent.

The developer used in the present invention can further contain an organic solvent. Examples of organic solvents include ethylene glycol monophenyl ether, benzyl alcohol, n-
Propyl alcohol and the like are useful. The content of the organic solvent in the developer composition is preferably 0.5 to 15% by weight, more preferably 1 to 5% by weight.
Weight percentage.

The developer may further contain a surfactant, if necessary.

The following additives can be added to such a developer in order to further improve the developing performance.
Neutral salts such as NaCl, KCl, KBr, etc. described in No. 8-75152, and EDTA described in JP-A-58-190952.

Chelating agents such as NTA, [C0(N113)]5Cfz, CoC1z described in JP-A-59-121336,
complexes such as 61120, 7-ionic or amphoteric surfactants such as flukylnaphthalenesulfonic acid compounds described in JP-A No. 50-51324, N-tetradecyl-N, N-dihydroxyethyl betaine, and tetra-ionic surfactants such as U.S. Pat. No. 4,374,920. Nonionic surfactants such as methyldecynol, cationic polymers such as the quaternized methyl chloride of p-methylaminomethylpolystyrene described in JP-A-55-95946, JP-A-56-142528. an amphoteric polymer electrolyte such as a copolymer of vinylbenzyltrimethylammonium chloride and sodium acrylate as described;
Reducing inorganic salts such as sodium sulfite described in JP-A-57-192952, non-fi +7 tium compounds such as lithium chloride described in JP-A-58-59444, JP-A-50-34
Organolithium compounds such as lithium benzoate described in No. 442, organometallic surfactants containing Si%Ti etc. described in JP-A No. 59-75255, organoborine compounds described in JP-A-59-84241, European Patent No. 101010
4 of the tetraalkylaminium oxide etc. described in No.
Examples include class ammonium salts.

Various conventionally known methods can be used to develop the 25th plate with such a developer.

That is, a method in which a developer is sprayed from a number of nozzles onto the image-exposed photosensitive layer of the 25th plate, a method in which the developer is immersed in a large amount of the developer, and a method in which the developer is applied to the surface of the PSS photosensitive layer using a roller. Examples include. It is also possible to use a method in which, after supplying the developer to the photosensitive layer of the 25th plate as described above, or by lightly rubbing the surface of the photosensitive layer with a brush or the like while immersed in the developer.

The development conditions can be set appropriately according to the above-mentioned development method, 25 plate size, properties of the developer, etc.Also, there may be multiple development tanks, and even if the developer or development conditions are different. good.

In order to compensate for fatigue due to the 25th edition or absorption of carbon dioxide in the air, developer replenisher may be added to the developer depending on the state of fatigue. The lithographic printing plate thus obtained is treated with an aqueous solution containing a surfactant solution without washing with water or after washing with water.

In the present invention, an aqueous solution containing a surfactant stabilizes the dispersion of the developer components, dissolved photosensitive layer composition, etc. that are brought in by adhering to the developed planographic printing plate, and even after drying, they remain fixed to the surface of the planographic printing plate. This is thought to have the effect of preventing

Such surfactants include polyoxyethylene furkyl ethers, polyoxyethylene furkylphenyl ethers, polyoxyethylene polystylphenyl ether, polyoxyethylene polyoxypropylene furkyl ether, glycerin fatty acid partial ester, and sorbitan fatty acid partial ester. , pentaerythritol fatty acid partial esters, propylene glycol monofatty acid esters, sucrose fat #Ie fraction esters, polyoxyethylene sorbitan fatty acid partial esters, polyoxyethylene sorbitol fatty acid partial esters, polyethylene glycol fatty acid esters, polyglycerin Fatty a partial esters, polyoxyethylenated castor oils, polyoxyethylene glycerin fatty acid partial esters, fatty acid jetanolamides, N,N-bis-2-hydroxyfurkylamines, polyoxyethylene alkyl heptamine, triethanol Nonionic surfactants such as amine fatty acid esters, triflukylamine oxide, fatty acid salts, avicenoates, hydroxyalkanesulfonates, alkanesulfonates, dialkyl sulfo(acid ester salts, linear alkylbenzene sulfonates) , branched [furkylbenzenesulfonates, alkylnaphthalenesulfoneprobylsulfonelenealkylsulfophenyl ethers, N-methyl-N-oleyl taurine sodium, N-furkylsulfosuccinic acid monoamide disodium salts, petroleum sulfonates, Sulfated castor oil, sulfated beef leg oil, sulfate ester salts of fatty acid furkyl esters, alkyl sulfate ester salts, polyoxyethylene alkyl ether sulfate ester salts, fatty acid monoglyceride sulfate ester salts, polyoxyethylene alkyl phenyl ether sulfate ester salts, polyoxy Ethylene styryl 7-tunyl ether sulfate ester salts, alkyl phosphate ester salts, polyoxyethylene alkyl ether phosphate ester salts,
7 such as polyoxyethylene alkyl phenyl ether phosphate ester salts, partially saponified products of styrene-maleic anhydride copolymer, partially saponified products of olefin-maleic anhydride copolymer, naphthalene sulfonate formalin composites, etc. Ionic surfactants, alkylamine salts, quaternary ammonium salts, polyoxyethylene alkylamine salts, cationic surfactants such as polyethylene polyamine derivatives, carboxybetaines, aminocarboxylic acids, sulfobetaines, 7-minosulfate esters Examples include amphoteric surfactants such as imidazolines and imidazolines.

Among the surfactants listed above, polyoxyethylene includes polyoxymethylene, polyoxypropylene,
The term "polyoxyalkylene" such as polyoxybutylene can also be used interchangeably, and surfactants thereof are also included, and the same applies in the following description.

Among these, polyoxyethylene alkyl ethers,
Polyoxyethylene alkylphenyl ethers, polyoxyethylene polystyrylphenyl ethers, polyoxyethylene polyoxypropylene furkyl ethers, glycerin fatty acid partial esters, sorbitan fatty acid S-class esters, pentaerythritol fatty acid partial esters, propylene glycol mono Fatty acid esters, polyoxyethylene sorbitan fatty acid partial esters, polyoxyethylene glycerin fatty acid partial esters, polyethylene glycol fatty acid esters, polyoxyethylated castor oil, dialkyl sulfosuccinates, furkylbenzene sulfonates, alkylnaphthalene sulfones FlkmM, alkyl sulfate ester salts, fatty acid salts, alkyl phosphate ester salts, naphthalene sulfonate formalin condensate, polyoxyethylene alkyl 7 amine salts, furkylamine salts, and quaternary ammonium salts are oil-sensitive in the image area of a lithographic printing plate. Among these, polyoxyethylene alkylphenyl ethers, polyoxyethylene polystyrylphenyl ethers, holoxyethylene furkyl ethers, glycerin fatty acid partial esters,
Sorbitan Yufat PIla! lS classification esters, polyoxyethylene sorbitan fatty acid partial esters, pentaerythritol (pentaerythri)-class esters, propylene glycol monofatty acid esters, polyethylene glycol fatty acid esters, dialkyl sulfo(acid ester salts, alkyl sulfate ester salts) , alkylbenzenesulfonic acid salts are particularly preferred.

The most preferred are alkylbenzene sulfonic acid salts and dialkyl sulfosuccinate ester salts, which have strong dispersing power.

The above-mentioned surfactants can be used alone or in combination of two or more, and the amount in the aqueous solution is about 0.1% to about 20% by weight, more preferably 0.5% by weight.

It is used in a range of 10% by weight to 1% by weight.

The pH of the aqueous solution containing the surfactant in the present invention is 1 to 1.
Used in the range 0. In order to adjust the aqueous solution to this pH, it is preferable to contain either or both of an acid and a water-soluble salt as a buffer.

Details of 41 shock agents are described in, for example, "Chemical Handbook Basic Edition ■" published by the Chemical Society of Japan, February 20, 1972, f55 edition, published by Maruzen Co., Ltd., pages 1312-1320, and these can be applied as is. be able to.

Suitable acids and water-soluble salts include molybdic acid, boric acid,
Acids such as nitric acid, sulfuric acid, phosphoric acid, polyphosphoric acid and other water-soluble organic acids such as black isoic acid, acetic acid, oxalic acid, tartaric acid, benzoic acid, succinic acid, citric acid, malic acid, lactic acid, and p-)luenesulfonic acid. I can give you the salt. More preferred salts are water-soluble alkali metal salts and ammonium salts, and particularly preferred are molybdates such as ammonium molybdate, phosphates such as sodium phosphate, polyg4 salts such as potassium tetrapolyphosphate and sodium trimetaphosphate, and oxalic acid. These are oxalates such as sodium, tartrates such as potassium tartrate, succinates such as sodium succinate, and citrates such as ammonium citrate. The acid and the water-soluble salt can be used alone or in combination of two or more.

More preferred D H of aqueous solutions containing these surfactants
is 1.5-8. The most preferred pH is 2.0-6.
5, and in this case, the desensitization performance of the non-image areas of the lithographic printing plate becomes higher.

In addition, in the plate making method of the present invention, developer components are brought into the aqueous solution, so in order to neutralize this, an amount of salt and/or acid is added in advance according to the planned treatment area of the PS plate. It is preferable to leave it there.

The amount of acid and salt added to the aqueous solution is not particularly limited, but the total amount of acid and salt is about 10% of the total amount of the aqueous solution.
It is preferable that the weight is 1% or less.

More preferably, it is used in a range of 0.01 to 6% by weight.

In the present invention, the aqueous solution containing the surfactant further includes sorbic acid, preservatives such as ethyl p-oxybenzoate, fungicides, probyl gallate, 2.6-di-t-butyl-4-ethylphenol, 2. An antioxidant such as 6-not-butyl-4-methylphenol may be included.

By adding a small amount of these preservatives, antifungal agents, and antioxidants, deterioration in quality due to storage of the aqueous solution can be prevented, but the preferable amount is 0.00.
It is 1 to 5% by weight.

It is preferable that the aqueous solution containing the surfactant in the present invention contains a lipophilic substance.

As a result, the image area of the lithographic printing plate shows higher oil sensitivity, which not only makes it easier to build up the developing ink, but also makes it easier to apply the plate surface protectant after treatment with the aqueous solution. It is possible to strongly suppress the decrease in oil sensitivity.

Preferred lipophilic substances include organic carboxylic acids having 5 to 25 carbon atoms, such as oleic acid, lauric acid, valeric acid, nonylic acid, capric acid, mystilic acid, palmitic acid, castor oil, and the like. These lipophilic substances can be used alone or in combination of two or more.

The lipophilic substance contained in the aqueous solution containing the surfactant in the present invention is 0,005% based on the total amount thereof.
from about 10% by weight, more preferably from 0.05 to 5% by weight
is within the range of

In the present invention, it is preferable that the amount of the developer on the lithographic printing plate after development be squeegeeed with as little force as possible. This is because contamination caused by the developer is prevented as much as possible, and processing ability with an aqueous solution containing a surfactant is increased.

Therefore, the amount of developer remaining on the lithographic printing plate after squeegeeing is preferably 12 m/m2 or less, more preferably 9 m1/m2 or less, and most preferably 5 m//m2 or less.
It is less than or equal to n2.

There are various methods of treatment with an aqueous solution containing a surfactant, such as immersion, application with a roller, and spraying from multiple nozzles onto a planographic printing plate or roller. By repeatedly using the aqueous solution and ejecting it from multiple nozzles at the same time, it is possible to greatly reduce the amount of aqueous solution containing the surfactant used per PS plate to be processed, thereby preventing printing stains. This is preferable because the effect of

The flow rate of the aqueous surfactant solution supplied onto the lithographic printing plate is preferably if/win, 401/etin or more, and preferably 3 to 20ffi/win.

It is desirable that the lithographic printing plate treated with an aqueous solution containing a surfactant be squeegeeed so that the amount and thickness of the aqueous solution coated are as uniform and appropriate as possible.

Desired application amount is 1+*1/2 or more, 20m1/2
It is as follows.

A more preferable coating amount is 2 ml/m" or more and 10 ml/m" or less, which reduces coating unevenness including the edge portions (commonly called selvedges) of the lithographic printing plate.

Methods of squeegeeing the plate surface of a planographic printing plate include, for example, using an air knife to scrape out the liquid, or passing the planographic printing plate between a pair of elastic rollers whose surfaces are coated with an elastic material such as rubber, and using the nip pressure to squeeze out the liquid on the plate surface. or by placing an elastic material with a smooth surface along the transport path of the lithographic printing plate.
It is possible to adopt a method of scraping off the liquid on the plate by bringing the plates into sliding contact.

A more effective squeegee method is a method in which a planographic printing plate is passed between a pair of elastic rollers, and a load is applied to the pair of rollers, and more preferably a third load roller is placed on top of the pair of rollers. It is.

The above elastic materials include natural rubber, cis-polyisoprene rubber, styrene-butanoene rubber, cis-polybutadiene,
Chloroprene, butyl rubber, nitrile butadiene rubber,
Examples include ethylene propylene rubber, Hypalon (chlorosulfonated polyethylene), acrylic rubber, urethane rubber, silicone rubber, fluororubber, neoprene rubber, polysulfide rubber, and plastics.

Butyl rubber, nitrile butadiene rubber, ethylene propylene rubber, acrylic rubber, silicone rubber, fluorine rubber,
Since polysulfide rubber has excellent oil resistance, it is suitable and preferable for rollers in the surfactant aqueous solution treatment section.

Furthermore, in a method of passing a lithographic printing plate between a pair of elastic rollers with a squeegee, and more preferably a method of treating the lithographic printing plate with an aqueous surfactant solution by spraying it from a number of nozzles, the lithographic printing plate may be treated with an aqueous surfactant solution. After passing through
In order to save unnecessary power, it is preferable that the processing device be designed so that the conveyance by the pair of rollers and the ejection by the nozzle are small (both one is stopped (hereinafter simply referred to as "stop")).

However, during this pause period, the aqueous surfactant solution often accumulates on the contact area between the pair of rollers and dries and solidifies, and in this case, the coating film thickness of the aqueous surfactant solution is As a method to avoid this situation, which tends to result in non-uniformity, there is a method of keeping the pair of rollers rotating even while the surfactant aqueous solution treatment is paused, and a method of rotating the pair of rollers during the treatment and/or while the treatment is paused. It is preferable to use at least one method, such as a method of delaying the drying of the pair of rollers by jetting the aqueous surface-active M solution onto the pair of rollers from a nozzle.

In the present invention, there must be two or more treatment steps using an aqueous solution containing a surfactant, but these steps are preferably continuous.

Further, it is particularly advantageous when the treatment with an aqueous solution containing a surfactant is directly performed without a washing step after development. Furthermore, it has two consecutive processing steps using aqueous solutions containing surfactants, and the processing solution of the first processing step through which the plate passes is intermittently or continuously replenished with a portion of the processing solution of the other processing step. In this case, it is more preferable to replenish the processing solution in the latter half of the treatment process with unused processing solution.

It is preferable that the lithographic printing plate treated with an aqueous solution containing a surfactant be dried to prevent dust from adhering thereto and to facilitate handling.

The preferred drying temperature is 20-120°C. The lithographic printing plate thus obtained can be subjected to various steps such as development ink application, addition, correction such as erasure, and treatment with a plate surface protectant.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

(Example) Example 1 An aluminum plate with a thickness of 0.3 parts m was electrochemically roughened in a nitric acid solution, washed, and anodized in a sulfuric acid solution to give a roughness of 2.5 g/a2. Form an oxide film on the surface of the aluminum plate.

After washing with water and drying, 3 parts of the esterified product of resorcin benzaldehyde resin synthesized according to the example of JP-A-56-1044 and 7-toquinone 1,2-)7-nodo-5-sulfonyl chloride, 9 parts of cresol-formalin novolak resin, and A photosensitive solution prepared by dissolving 0.12 parts of Victoria Pure Blue 8011 (manufactured by Hodogaya Chemical Industry Co., Ltd., dye) in 100 parts of 2-nodoxyethanol was applied onto the above support and dried. P with photosensitive layer
I got the S version.

The plate obtained in this way is 800zzX 100h+
A large number of sheets were prepared by cutting them into J-sized pieces.

Next, this sample was exposed to light for 60 seconds using a 2 part M metal halide lamp from a distance of 80 cm through a transparency having a uniform halftone image over the entire surface with a halftone image area ratio of about 80%. The processed sample was developed using an automatic developing machine shown in FIG.

In the figure, 10 is a developing section, and 20 and 20' are surfactant processing sections. For the PS plate guided by the transport roller pair 1 and carried into the developing section, a developer sent from the developer storage tank 11 via a pump is supplied onto the 18th plate surface from the developer supply nozzle 13, Next, it is developed via a brush roller 3, squeegeeed by a squeezing roller 2, and then transferred to the next surfactant processing section! Enter section 20. The surfactant is supplied from the surfactant liquid storage ff121 via a pump onto the 18th plate surface from the slurry 23, squeegeeed by the squeezing roller 2, enters the next surfactant processing section 20', and is treated with the first surfactant. Agent processing department!
It is processed in the same way as part 20. However, fresh liquid is supplied to the second surfactant treatment liquid storage tank 21', and the liquid that has exceeded the second surfactant liquid tank 22' is transferred to the first surfactant liquid storage tank a. 21. The surfactant liquid that has overflowed the same kind is sent to the waste liquid tank 24.

The formulations of the developer, developer replenisher, and surfactant solution used in this case are as follows.

Developer potassium silicate aqueous solution (to si02/, 0 molar ratio 1.2,
(SiO content 4% by weight) 50 parts by weight Sodium isopropylna-7-talensulfonate 0.05 parts by weight 11 parts Nostyrenated phenol polyethylene oxide adduct (trade name A-500, manufactured by Seisho Co., Ltd.)・Q,Q
5fi 41 parts water
...50 weight 1 part developer replenisher potassium silicate aqueous solution (20 molar ratio 1.2 to SiO□/
SiO2 content (fi4% by weight) Surfactant water: /#liquid no (2-ethylhexyl) sulfosuccinic acid ester sodium salt...30 parts Sodium dihydrogen phosphate dihydrate...10 parts citric acid-water Salt... 2 parts water
...100
0 parts 401 developer solution in the developer storage tank 11, 101 parts each of the above surfactant aqueous solution in the surfactant solution storage Wj21.21'
In addition, the developer storage tank is filled with replenisher at 400ml for each plate.
11% surfactant liquid storage! fJ21' is replenished with 1011 surfactant solutions for each plate. Therefore, the first surfactant liquid, 1ilW! 21 is replenished with the same amount of liquid from the second surfactant tank 22'. In this way, 2000 PS plates were processed, and good printed matter was obtained in all cases.

Comparative Example 2 In the case shown in FIG. 1, the second surfactant treatment section 20' was not provided, but the other conditions were the same as in Example 1. As a result, the printed matter printed with the 400th plate was stained.

Example 2 In Example 2, the automatic developer (v8!) shown in Figure 12 was used. In this figure, the developing unit 10' is installed in the song of the developing unit 10,
2+ developing sections were provided. Surfactant treated part is Pt51
Same as the figure. Figure PA2 shows that in the first developing section 10'', a developer is supplied from a developer supply nozzle 13' onto a 18-plate surface conveyed along an inclined plate 16 through a base slit 15 made of two plates. The liquid is supplied, passes through the liquid reservoir 17, passes through the skewer roller 18, is developed in the next dip tank 14, passes through the brush roller 3, and enters the next development R10.In this case, the brush row 2 is omitted in the processing section 10. There is.

The following steps are the same as in FIG.

In this Example 2, the developer was the same as in Example 1, and 9200 ml of the developer was supplied from the supply nozzle 13' through the base slit.

The following aqueous solution was used as the surfactant solution.

Lauryl alcohol sulfate ester sodium salt...30 parts Sodium dihydrogen phosphate dihydrate...10 parts Citric acid-hydrate...2 parts water
...1000 copies In this case, 2200 PS plates were processed and good results were obtained.

(Effect of the invention) According to the present invention, in the water washing step after the development treatment of the 28th plate,
First of all, it is a method that uses less wastewater and causes less pollution and environmental contamination, and it is also a treatment method that does not use washing water or can efficiently carry out corrective work such as erasing and adding after washing with a small amount of washing water. And, furthermore, the surfactant aqueous solution J! [! It is not possible to provide a processing method that can increase the life of the solution and reduce the cost of plate making.

[Brief explanation of the drawing]

1 and 2 are schematic side sectional views showing the structure of an automatic developing machine showing an embodiment of the present invention. 1O110': Developing section, 11: Developer storage tank, 12.12': Developer tank, 13.13': Developer supply nozzle,

Claims (1)

[Claims] A method of automatically transporting and developing an exposed photosensitive lithographic printing plate using an automatic developing machine, characterized by including at least two treatment steps with an aqueous solution containing a surfactant after the development step. A method of processing photosensitive lithographic printing plates.