JPH04249259A - Processing method for photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To stably process a negative and a positive type printing plate by the same automatic developing machine with the small consumption of a liquid developer by supplying a negative-positive common-use liquid developer or dedicated liquid developers corresponding to kinds in a foaming state by a specific amount for each 1m<2> area of a photosensitive planographic printing plate to be processed and performing a developing process. CONSTITUTION:The liquid developer is supplied by 10-200ml for each planographic printing plate to be processed to perform the developing process. In a developer supply tank 44a, the developer foams with air fed into the developer from an air blowing-in pipe 45a and the foaming liquid developer is sent in the gap of a liquid developer supply slit 6 from supply openings 61a and 62b. As this gap is filled with the liquid developer, the planographic printing plate is carried in the gap and both the top and reverse surfaces of the photosensitive planographic printing plate is brought into contact with the foaming liquid developer to carry out the development.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a method for processing photosensitive lithographic printing plates, and more specifically, the present invention relates to a method for processing photosensitive lithographic printing plates, and more specifically, a negative-working photosensitive lithographic printing plate and a positive-working photosensitive lithographic printing plate are processed in the same automatic developing machine. The present invention relates to a method of developing in sequence, and is also suitable for developing a photosensitive lithographic printing plate having photosensitive layers on both sides of a support.

0002

[Prior Art] When processing a large number of exposed photosensitive lithographic printing plates, it is common to use an automatic developing machine, and the developer used at the same time is water-free due to odor and environmental conservation issues. Alkaline developing solutions, which use the main solvent as the main solvent, are the mainstream.

[0003] When processing exposed photosensitive planographic printing plates in an automatic developing machine, there are two methods: developing by spraying a shower of developer while horizontally transporting the photosensitive planographic printing plate, and using a large amount of developer. A method of developing is carried out by immersing a photosensitive planographic printing plate in a developing tank containing a curved version while conveying it. In all of these processing machines, it is necessary to prepare a large amount of developer to process one photosensitive lithographic printing plate. Additionally, in order to use the developer economically, the developer is recycled and reused, and during this process, in addition to deterioration of the developer due to processing, deterioration of the developer occurs due to the absorption of carbon dioxide gas from the air, which often results in deteriorated developer. The solution had to be replaced, making it extremely troublesome to manage the developing process.

[0004] Furthermore, in order to improve the above-mentioned drawbacks, when processing a photosensitive lithographic printing plate with a large amount of circulating and reusing developer, a method is known in which a replenisher is replenished to keep the development process stable. JP-A-50-144502, JP-A No. 55-1
It is disclosed in publications such as No. 15039 and No. 58-95349. However, even with such a replenishment method, although the frequency of liquid exchange is reduced, liquid exchange is necessary, and the problem of replenishment accuracy and replenishment fluctuations due to product differences between photosensitive planographic printing plates 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 adjustment and maintenance.

[0005] A method aimed at eliminating the troublesome replenishment method and saving developer is disclosed in Japanese Patent Application Laid-Open No. 61-24675.
It is described in Publication No. 0. This is done by using an automatic developing machine to apply an alkaline developer containing water as a main solvent to each photosensitive planographic printing plate to be processed.
This invention relates to a method for developing a photosensitive lithographic printing plate, which is characterized in that the developer is supplied to the plate surface at a rate of 70 to 700 ml per developer. In the area of 200 ml or less per 1 m2 of printing plate, depending on the developer supply method, it may be difficult to uniformly supply the developer to the entire plate surface of the photosensitive planographic printing plate being processed, and uniform development cannot be achieved. There was a problem. Furthermore, when developing a photosensitive lithographic printing plate (hereinafter referred to as a "double-sided plate") in which photosensitive layers are provided on both sides of the support, the developer supplied to the lower surface may drip down. However, there was a problem that stable development was not possible.

[0006] Also, for each photosensitive lithographic printing plate that is transported, a new solution of a dedicated developer depending on the type of the photosensitive lithographic printing plate or a common developer that can commonly develop different types of photosensitive lithographic printing plates is supplied. By developing, multiple types of photosensitive lithographic printing plates can be recirculated and recycled without using an automatic developing machine with multiple development processing sections or without replacing the developer, including a developer replenishment system. There is a known development technique that does not cause problems regarding development management in the method used (Japanese Patent Laid-Open No. 61-2
No. 48051, No. 61-248052). However, when the amount of developer consumed is reduced, the problem of impairing the uniformity of development on the plate surface and the problem of stability of development on the lower side of the double-sided plate remain unsolved.

[0007]

OBJECTS OF THE INVENTION An object of the present invention is to provide a method for processing photosensitive lithographic printing plates in which the drawbacks of the above-mentioned conventional techniques are improved. That is, by providing a method for processing photosensitive lithographic printing plates that can economically and stably process negative-working photosensitive lithographic printing plates and positive-working photosensitive lithographic printing plates in the same automatic processor. Another object of the present invention is to provide a processing method that can stably develop both sides of a double-sided plate.

[0008]

[Structure of the Invention] In order to achieve the above object, the processing method of the present invention involves conveying a negative-working photosensitive lithographic printing plate and a positive-working photosensitive lithographic printing plate in an arbitrary order using the same automatic developing machine. In a method for processing a photosensitive lithographic printing plate that is subjected to development processing,
For each photosensitive lithographic printing plate to be processed, a substantially unused negative/positive common developer or a special developer depending on the type is made into a foam, and 10% per m2 of the photosensitive lithographic printing plate to be processed. It is characterized in that ~200ml is supplied and developed. Hereinafter, the method of the present invention will be explained with reference to the drawings showing an example of an apparatus used in the method of the present invention. Note that in the following description, the same components are given the same reference numerals.

FIG. 1 is a schematic sectional view showing an example of an automatic processor having an embodiment of the apparatus for carrying out the method of the present invention. In the figure, 1 is a developing section for developing, 2 is a washing section for washing with water, and 3 is a rinsing section for rinsing or desensitizing.
The gum section S is a conveyance path for the photosensitive planographic printing plate.

In the developing section 1, a preheat roller 4 heats the photosensitive lithographic printing plate carried in to a predetermined temperature range before development. As a roller having a heating means, a nichrome wire or the like is buried as a heating element inside a hollow pipe made of a metal with high thermal conductivity (for example, aluminum, iron, etc.), and the outer surface of the metal pipe is made of polyethylene, It has a structure covered with a plastic sheet such as polystyrene or Teflon. For details, refer to Japanese Patent Application Laid-Open No. 64-80962.

5 is a pair of transport rollers; 6 is a developer supply slit for supplying a foamy developer to the plate surface of the photosensitive planographic printing plate;
7 is a conveyance roller, 8 is a brush roller that rubs the surface of the photosensitive lithographic printing plate to promote development, and 9 is a squeeze roller, which are configured so that the photosensitive lithographic printing plate is conveyed horizontally. . The transport roller 7 used has a structure that prevents the foamy developer supplied to the lower surface of the photosensitive planographic printing plate from being squeezed. For example, the skewer roller shown in FIG. 2(b) of Japanese Patent Application Laid-Open No. 63-85745 can be used.

Next, the supply relationship of the foamy developer to be sent to the developer supply slit 6 will be explained. The system for supplying the foamy developer to the developer supply slit 6 has two systems so that two types of developer can be supplied, and the system can be switched depending on the type of photosensitive planographic printing plate to be processed. It is composed of The first system (developing solution supply system A) includes a concentrated developer tank 40a containing a concentrated developer, a dilution water tank 41 containing water for diluting the concentrated developer, and a dilution water tank 41 containing water for diluting the concentrated developer. Developer mixing tank 4 for the developer to be used
2a, metering pumps 43a, 43c, a developer supply tank 44a that blows gas such as air or nitrogen into the developer to make it foamy, and a gas insertion pipe 45 that blows gas into the developer.
a. As a system for blowing gas into the metering pump 47a and the developer supply tank 44a, it is filtered by an air filter 51, is pressurized into the air tank 53 by a compressor 52, and is passed from the air tank 53 through the electromagnetic valve 54a to the developer supply tank 4.
It mainly consists of a system that pumps gas to 4a (
Including the drawings below, *n and *n (n is a positive integer) are connected by pipes).

The second system (developer supply system B) also has the same structure as the developer supply system A, and a part thereof is common to the developer supply system A. The developer supply system B includes a concentrated developer tank 40b for storing a concentrated developer, a dilution water tank 41 (common with the developer supply system A) for storing water for diluting the concentrated developer, and a tank for mixing the concentrated developer and water. A developer mixing tank 42b and metering pumps 43b and 43d are used as a developer to be used for development.
, a developer supply tank 44b that blows gas such as air or nitrogen into the developer to make it foamy, a gas insertion pipe 45b that blows gas into the developer, a metering pump 47b, and a system that pumps gas to the developer supply tank 44b. It mainly consists of an air filter 51, a compressor 52, an air tank 53 (these are common to the developer supply system A), and a solenoid valve 54b. When the device is in operation, the operation of the compressor is controlled so that the pressure of the gas in the air tank 53 is maintained within a predetermined range.

In the above device, the gas insertion pipe 45a
, 45b, that is, the gas inlet into the developing solution, is a nozzle having a fine hole for finely dividing the gas into the developing solution and generating bubbles. A closed pipe with an inner diameter of about 5 to 50 mm provided with many pores (pore diameter of about 0.05 to 2 mm), a sintered body of glass, etc. can be used. A device for adjusting the temperature of the gas may be added to the pipelines feeding the developer supply tanks 44a and 44b.

[0015] Switching between the two developer supply systems described above is as follows:
The switching may be performed manually, or the switching may be performed by detecting the type of photosensitive planographic printing plate being carried in. The developer supply slit 6 has an upper member 61 and a lower member 62, each of which has a foam developer supply port 61a,
62a, 61b, 62b are provided, and the developer supply system A
A foamy developer is supplied from the developer supply system B to supply ports 61a and 62a, and a foamy developer is supplied from the developer supply system B to supply ports 61b and 62b, respectively. It is preferable that the upper member 61 and the lower member 62 are provided so that their inner surfaces are parallel to the conveying surface with a small distance from each other, but they are slightly offset from parallel to the conveying direction (for example, in a horizontal plane). (e.g., lowering in the transport direction). The gap G between the upper member 61 and the lower member 62 is preferably 50 mm or less, more preferably 5 to 5 mm.
30 mm, especially 5 to 20 mm is preferred. Further, it is preferable to apply means for reducing the conveyance resistance, such as providing rollers or implanting nylon single yarn, etc., on the surface of both members, especially the lower member 62, on the side of the conveyance path. The developer supply slit 6 is provided with a temperature adjustment device (not shown) so that the supplied foamy developer is maintained within a predetermined temperature range.

Stainless steel, plastics (hard vinyl chloride, polyethylene, polypropylene, polycarbonate, polystyrene, etc.) and the like can be used as the material for the developer supply slit and other members with which the developer comes into contact. As other members such as the brush roller 8 and the squeeze roller 9, known ones can be used.

[0017] In the water washing section 2 and the rinse/gum member 3,
5 is a pair of conveying rollers, 9a and 9b are squeeze rollers, 21
31 is a rinsing water tank containing rinsing water, 31 is a rinsing/gum liquid tank containing rinsing liquid or desensitizing liquid (gum liquid), 2
2 and 32 are shower nozzles, and 24 and 34 are pumps.

Next, the control relationship of the illustrated device will be described. Reference numeral 70 denotes an optical sensor for detecting the loading of the photosensitive material and its length in the conveying direction, and controlling the operation of the apparatus, which will be described later, by a control mechanism (not shown). The control mechanism includes an optical sensor 7
Based on the detection signal of 0, the carry-in and conveyance direction length of the photosensitive planographic printing plate is detected, and the preheat roller 4, conveyance roller pair 5, conveyance roller 7, brush roller 8, squeeze rollers 9, 9a, 9b, metering pump 43a, 43c, 47a,
Solenoid valve 54a, (or metering pump 43b, 43d, 47
The solenoid valve 54b) and the pumps 24 and 34 are configured to operate at predetermined timings and for operating times depending on the length of the photosensitive planographic printing plate in the transport direction.

Next, the method of the present invention and the operation of the apparatus shown in the figure will be explained with reference to FIG.

First, when a photosensitive planographic printing plate is inserted from the left end of the figure in the apparatus, based on the detection signal of the optical sensor 70,
The conveyance of the photosensitive planographic printing plate and the conveyance length of the photosensitive planographic printing plate are detected, and the preheat roller 4, the conveyance roller pair 5, the conveyance roller 7, and the squeeze rollers 9, 9a, and 9b are operated by a control device (not shown). A photosensitive planographic printing plate is conveyed horizontally to the right in the figure. Also, based on the switching of the developer supply system, the metering pump 43
a, 43c, 47a, solenoid valve 54a (or metering pump 4
3b, 43d, 47b, solenoid valve 54b) are activated, and the foamy developer is supplied to the supply ports 61a, 62a (or 61b62b).
The developer is supplied from the developer to the developer supply slit 6.

In the developer supply tank 44a (or 44b), the developer becomes foamy due to the gas pumped into the developer from the gas blowing pipe 45a (or 45b), and the supply ports 61a, 62a (or 61b, 62b) ) is fed into the gap G of the developer supply slit 6, and the gap G
As the space is gradually filled with the foamy developer, the photosensitive planographic printing plate is carried into the gap G, and both upper and lower surfaces of the photosensitive planographic printing plate come into contact with the foamy developer, and development is performed. The photosensitive lithographic printing plate holding the foamy developer on its plate surface is then rubbed by a brush roller 8 and squeezed by a squeeze roller 9 to complete development. Next, the photosensitive planographic printing plate is transported to a water washing section 2 and a rinsing/gum section 3, where it is subjected to various treatments.

FIG. 2 is a schematic cross-sectional view showing another example of a processing apparatus for carrying out the method of the present invention. In the same figure, the processing equipment after development is omitted from illustration. In the figure, 4 is a preheat roller that heats the photosensitive lithographic printing plate being carried in to a predetermined temperature range before development, 80 is a developing tank, 81 is a cover of the developing tank 80, and 5, 84, and 85 are pairs of conveying rollers. ,
86 and 87 are conveyance rollers, 8 is a brush roller, and 9 is a squeeze roller. Each of the rollers described above is curved downward as shown in the drawing at the developing tank 80 and is transported through the transport path S.
The photosensitive planographic printing plate is configured to pass through the foamy developer filled in the curved portion of the plate.

The developer tank 80 is provided with a supply port 82 through which a foamy developer is supplied, and a conduit 83 through which the developer, which has ruptured and returned to a liquid state, is returned to the developer supply tank 44a. Further, the developing tank 80 is controlled by a temperature adjusting device (not shown).
The foam-like developer inside is kept within a predetermined temperature range. As the conveyance roller pair 84 and the conveyance roller 86, skewer rollers can be used similarly to the conveyance roller 7 described above. Further, it is preferable to use skewer rollers as the pair of conveyance rollers 85 and the conveyance roller 87 in the same way as the conveyance roller 7 so that the developing solution adhering to the plate surface is not squeezed.

The developer supply system is constructed in one system so that negative and positive type photosensitive lithographic printing plates are developed using one type of common negative and positive developer. It has a configuration according to the above, and includes a concentrated developer tank 40a containing a concentrated developer, a dilution water tank 41 containing water for diluting the concentrated developer, and a developer used for developing by mixing the concentrated developer and water. A developer mixing tank 42a, metering pumps 43a, 43c, a developer supply tank 44a that blows air or a gas such as nitrogen into the developer to make it foamy, a gas blowing pipe 45a that blows gas into the developer, and a metering pump 47a. , and a system for blowing gas into the developer supply tank 44a, which mainly includes an air filter 51, a compressor 52, an air tank 53, and a solenoid valve 54a.

The foamy developer enters the supply port 82 and fills the space formed by the developer tank 80 and the cover 81, including at least the transport path S, and comes into contact with both sides of the photosensitive lithographic printing plate being transported. The image is then developed. The photosensitive planographic printing plate is rubbed with a brush roller 8 with foamy developer attached to both sides, and then squeezed with a squeeze roller 9 to complete the development.

FIG. 3 is a schematic sectional view showing another example of a processing apparatus for carrying out the method of the present invention. The apparatus shown in FIG. 1 is substantially the same as the apparatus shown in FIG. 1, except for the means for foaming the developer and the means for supplying the foamy developer to the photosensitive lithographic printing plate. In the figure, 4 is a preheat roller, 90a,
90b is a foaming spray nozzle, 91 is a cover that covers the foaming spray nozzle, 5 and 85 are a pair of conveyance rollers, 7 is a conveyance roller, 8 is a brush roller, 8a is a support plate that supports the photosensitive planographic printing plate from below, 9 is a squeeze roller. Each of the rollers forms a horizontal conveyance path.

The developer supply system is constructed so as to be able to supply two types of developer, and is the same as the apparatus shown in FIG. 1, except for the device that turns the developer into foam. In the apparatus shown in this figure, a foaming spray nozzle is used as a means for foaming the developer, and compressed gas from the air tank 53 and metering pumps 47c, 47d are supplied from the developer supply tanks 92a, 92b.
The developer is supplied to the foaming spray nozzles 90a and 90b, where it is made into a foam and is sprayed onto the photosensitive planographic printing plate. The foaming spray nozzles 90a, 90b are adjusted to a predetermined temperature range by a temperature adjusting device (not shown).

[0028] In the method of the present invention, it is preferable that the automatic developing machine used has means for identifying the plate type of the photosensitive lithographic printing plate being carried in. This method includes a method of using an optical sensor to determine the difference in spectral reflectance between negative and positive photosensitive layers, and a method of determining the difference in spectral reflectance between negative and positive photosensitive layers. There are two methods: a method in which a sensor is provided and discrimination is made based on the insertion position of the photosensitive lithographic printing plate, and a method in which an identification symbol is provided in advance on the photosensitive lithographic printing plate and the identification symbol is read optically for discrimination.

In the method of the present invention, it is preferable to preheat the photosensitive planographic printing plate before development. Compared to the conventional method of circulating and reusing a large amount of developer or the method of supplying a relatively small amount of non-foamy developer, development using a foamy developer is affected by the temperature of the photographic material being transported. Therefore, it is particularly effective for the stability of development to adjust the temperature of the photosensitive planographic printing plate to an appropriate temperature before development by preheating. Furthermore, the method of the present invention is particularly effective for processing double-sided plates.

In the present invention, it is preferable that the developer contains a surfactant in order to keep the developer stable in the form of a foam.

The surfactant may be nonionic, cationic, anionic or amphoteric.

[0032] Nonionic surfactants include polyethylene glycol type and polyhydric alcohol type, and both can be used. From the viewpoint of development performance, polyethylene glycol type nonionic surfactants are preferred, and among these, polyethylene glycol type nonionic surfactants are preferred, and among them, those having three or more ethyleneoxy groups (-CH2CH2O-) and HL
B value (HLB is Hydrophile-Lipophile
leBalance) is 5 or more (more preferably 8
-20, more preferably 15-20) nonionic surfactants are more preferred.

Among the nonionic surfactants, those having both ethyleneoxy and propyleneoxy groups are particularly preferred, and among these, those having an HLB value of 8 or more are more preferred.

Preferred examples of nonionic surfactants include compounds represented by the following general formulas [1] to [8].

[0035]

[Chemical formula 1]

In formulas [1] to [8], R represents a hydrogen atom or a monovalent organic group. The organic group includes, for example, a linear or branched alkyl group having 1 to 30 carbon atoms that may have a substituent {for example, an aryl group (phenyl, etc.)}, and an alkylcarbonyl group in which the alkyl moiety is the above-mentioned alkyl group. and a phenyl group which may have a substituent (for example, a hydroxyl group, an alkyl group as described above, etc.). a, b, c, m, n, x and y are each 1 to 4
Represents an integer of 0.

Next, specific examples of nonionic surfactants will be shown.

Polyethylene glycol, polyoxyethylene lauryl ether, polyoxyethylene nonyl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene behenyl ether,
Polyoxyethylene polyoxypropylene cetyl ether, polyoxyethylene polyoxypropylene behenyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene stearylamine, polyoxyethylene oleylamine, polyoxyethylene stearamide, Polyoxyethylene oleic acid amide, polyoxyethylene castor oil, polyoxyethylene abiethyl ether, polyoxyethylene lanolin ether, polyoxyethylene monolaurate, polyoxyethylene monostearate, polyoxyethylene glyceryl monooleate, polyoxyethylene Glycer monostearate, polyoxyethylene propylene glycol monostearate, oxyethylene oxypropylene block polymer, distyrenated phenol polyethylene oxide adduct, tribenzylphenol polyethylene oxide adduct, octylphenol polyoxyethylene polyoxypropylene adduct, glycerol monostearate sorbitan monolaurate, polyoxyethylene sorbitan monolaurate, etc.

The weight average molecular weight of the nonionic surfactant is 3
The range is preferably from 00 to 10,000, and from 500 to 5,000.
A range of is particularly preferred. One type of nonionic surfactant may be contained alone, or two or more types may be used in combination.

Cationic surfactants are broadly classified into amine type and quaternary ammonium salt type, and any of these can be used.

Examples of amine types include polyoxyethylene alkyl amine, N-alkylpropylene amine, N-
-Alkyl polyethylene polyamine, N-alkyl polyethylene polyamine dimethyl sulfate, alkyl biguanide, long chain amine oxide, alkylimidazoline, 1-
Hydroxyethyl-2-alkylimidazoline, 1-acetylaminoethyl-2-alkylimidazoline, 2-
Examples include alkyl-4-methyl-4-hydroxymethyloxazoline.

Examples of quaternary ammonium salts include long-chain primary amine salts, alkyltrimethylammonium salts, dialkyldimethylethylammonium salts, alkyldimethylammonium salts, alkyldimethylbenzylammonium salts, alkylpyridinium salts, and alkyltrimethylammonium salts. Norinium salt, alkylisoquinolinium salt, alkylpyridinium sulfate, stearamidemethylpyridinium salt, acylaminoethyldiethylamine salt, acylaminoethylmethyldiethylammonium salt, alkylamidopropyldimethylbenzylammonium salt, fatty acid polyethylene polyamide, acylamino Ethylpyridinium salt, acylcolaminoformylmethylpyridinium salt,
Stearooxymethylpyridinium salt, fatty acid triethanolamine, fatty acid triethanolamine formate, trioxyethylene fatty acid triethanolamine, fatty acid dibutylaminoethanol, cetyloxymethylpyridinium salt, p-isooctylphenoxyethoxyethyldimethylbenzylammonium salt, etc. There is. (“Alkyl” in the above compound examples refers to carbon atoms having 6 to 20 carbon atoms,
It represents a straight-chain or partially substituted alkyl, and specifically, straight-chain alkyl such as hexyl, octyl, cetyl, and stearyl are preferably used. ) Among these, water-soluble quaternary ammonium salt type cationic surfactants are particularly effective, and among them, alkyltrimethylammonium salts, alkyldimethylbenzylammonium salts, ethylene oxide-added ammonium salts, etc. are preferable. Also,
A polymer having a cationic component as a repeating unit is also a cationic surfactant in a broad sense, and is included in the cationic surfactant of the present invention. In particular, a polymer containing a quaternary ammonium salt obtained by copolymerizing with a lipophilic monomer can be suitably used.

[0043] The weight average molecular weight of the polymer is 300 to 50.
000, particularly preferably 500 to 5000
is within the range of These cationic surfactants can be used alone or in combination with
You may use more than one species in combination.

Examples of anionic surfactants include higher alcohol (C8 to C22) sulfate ester salts [for example, sodium salt of lauryl alcohol sulfate, sodium salt of octyl alcohol sulfate, ammonium salt of lauryl alcohol sulfate, "Teepo
1-81 (trade name, manufactured by Ciel Chemical Co., Ltd.), sodium chloride alkyl sulfate, etc.], aliphatic alcohol phosphate ester salts (e.g., sodium salt of cetyl alcohol phosphate ester, etc.), alkylaryl sulfonates (e.g., sodium salt of dodecylbenzenesulfonic acid, sodium salt of isopropylnaphthalenesulfonic acid, sodium salt of dinaphthalene disulfonic acid, sodium salt of metanitrobenzenesulfonic acid, etc.), sulfonic acid salts of alkylamides (for example, C17H33CO
N(CH3)CH2SO3Na, etc.), and sulfonic acid salts of dibasic fatty acid esters (for example, sodium sulfosuccinate dioctyl ester, sodium sulfosuccinate dihexyl ester, etc.). Among these, sulfonate salts are particularly preferably used.

As the amphoteric surfactant, a compound such as sodium N-methyl-N-pentadecylaminoacetate can be used.

The surfactant is preferably contained in the developer at a concentration in the range of 0.01 to 10% by weight.

In the present invention, the term "substantially unused developer" means a developer having the same developing ability as an unused developer, and includes a completely unused developer. It is also possible to mix used developers within a range that does not reduce the developing ability. For example, the developer once supplied to the photosensitive lithographic printing plate can be mixed with an unused solution. However, it is preferable to use the entire amount of unused liquid.

In the present invention, the amount of developer supplied is in the range of 10 to 200 ml per 1 m2 of photosensitive layer, preferably 50 to 200 ml, as described above, in the developer before it becomes foamy.
~150ml. In the present invention, since the developer is supplied in the form of foam to the photosensitive layer, a supply amount exceeding 200 ml is not required.
When the amount is less than ml, it is difficult to maintain development performance and uneven development is likely to occur. The diameter of the bubbles in the foamy developer is preferably smaller, preferably 1 mm or less, and more preferably 500 μm or less. The developer temperature is preferably 1
The temperature is in the range of 0 to 40°C, more preferably 25 to 35°C, and the development time is preferably in the range of 5 to 90 seconds, more preferably 10 to 60 seconds.

In the present invention, after applying the foamy developer to the photosensitive layer, a development promoting operation (such as rubbing with a brush or roller, spraying the developer onto the plate surface using a shower, etc.) can be performed.

The photosensitive lithographic printing plate and developer to which the present invention is applied include, for example, a negative photosensitive lithographic printing plate having a photosensitive layer using a diazo compound as a photosensitive component on an anodized aluminum support. and its developer; a positive-working photosensitive lithographic printing plate also using an o-quinonediazide compound as a photosensitive component; and its developer; a photoconductive layer is provided on the support as described above, and a toner image is formed by an electrophotographic method; After that, the photoconductive layer in the non-image area can be removed by an elution process, and the lithographic printing material and its developer are included.
The developer contains alkali silicate, organic solvent, surfactant,
A developing solution containing water as a main solvent and having a pH of 12 to 13.5 and containing an inorganic reducing agent, a chelating agent, etc. is included. More specifically, for example, JP-A-62-175757 No. 5
Photosensitive lithographic printing plates and their developers, such as those described in line 18 of the lower left column of the page to line 11 of the upper right column of page 7, such as JP-A-62-24263, JP-A-62-24264, JP-A-62
-25761, 62-35351, 62-73
No. 271, No. 62-75535, No. 62-89060
No. 62-125357, No. 62-133460, No. 62-159148, No. 62-168160,
Photosensitive lithographic printing plates and their developers as described in JP-A No. 62-175757, JP-A No. 62-175758, JP-A No. 63-200154, and JP-A No. 63-205658, and their developers, for example, JP-A-58-25477. Included are electrophotographic photosensitive lithographic printing plates and their developers as described in the publications.

Furthermore, for example, Japanese Patent Application Laid-Open No. 1-14904
No. 3, JP-A-1-150142, JP-A-1-1541
57, JP-A-1-154158, etc., which have a structure in which a silicone layer is laminated as a photosensitive layer and an ink repellent layer on a substrate, and their developers are included.

[0052]

[Examples] The present invention will be explained in more detail with reference to Examples below.

Example 1 A JIS-1050 aluminum plate with a thickness of 0.24 mm was immersed in a 2% aqueous sodium hydroxide solution and degreased, and then both the front and back surfaces were electrochemically treated in a dilute nitric acid solution. After the surface was roughened and thoroughly washed, it was anodized in a dilute sulfuric acid solution to form an oxide film of 2.5 g/m2 on both the front and back surfaces of the aluminum plate. After washing and drying the aluminum plate treated in this way, a photosensitive solution having the following composition was applied to both the front and back surfaces to a dry weight of 2.5 g/m2, and dried to form a positive photosensitive lithographic printing plate. Obtained.

(Photosensitive liquid) Naphthoquinone-1,2-diazide(2)-5-sulfonic acid ester of pyrogallol acetone resin (Japanese Patent Publication No. 1973-
Synthesized by the method described in Example 1 of Publication No. 28403)

... 1 part by weight m,p-cresol-
formaldehyde resin
…2 parts by weight tert-butylphenol-formaldehyde resin
…0.3 parts by weight Oil Blue #603 (Product name: Orient Chemical Industry)
(KK)
(manufactured by B.A.S.F., dye) …0.03 parts by weight Crystal Violet (manufactured by B.A.S.F., dye)
…0.03 parts by weight ethylene glycol monoethyl ether
...20 parts by weight A large number of positive-working photosensitive lithographic printing plates thus obtained were prepared, a transparent positive film was adhered thereto, and exposure was performed for 60 seconds from a distance of 70 cm using a 2 kW metal halide lamp.

On the other hand, JIS-105 with a thickness of 0.24 mm
1. An aluminum plate was immersed in a 20% sodium phosphate aqueous solution to degrease it, the front and back surfaces of the plate were electrochemically roughened in a dilute hydrochloric acid solution, and after thorough washing, anodization was performed in a dilute sulfuric acid solution. An oxide film of 5 g/m2 was formed on both the front and back surfaces of the aluminum plate. The aluminum plate treated in this way was further immersed in an aqueous sodium metasilicate solution to seal the holes, washed with water, and dried.
A photosensitive liquid of the following composition was applied to both the front and back sides, each dry weight 2.
．． It was coated at a concentration of 0 g/m2 and dried to obtain a negative photosensitive lithographic printing plate.

(Photosensitive solution) A combination of p-diazodiphenylamine and paraformaldehyde
Hexafluorophosphate of condensate......1 part by weight N-(4-hydroxyphenyl) methacrylamide copolymer (as described in Example 1 of Japanese Patent Publication No. 57-43890)......10 parts by weight Victoria Pure・Blue BOH (product name,
(manufactured by Hodogaya Chemical Industry Co., Ltd., dye) …0.2 parts by weight ethylene glycol monomethyl ether
...100 parts by weight A large number of negative photosensitive lithographic printing plates thus obtained were prepared, a transparent negative film was adhered thereto, and exposure was performed for 30 seconds from a distance of 70 cm using a 2 kW metal halide lamp.

SDN-21 (manufactured by Konica Corporation, a developer for negative photosensitive lithographic printing plates) is charged into the concentrated developer tank 40a of the automatic processor shown in FIG. After being diluted four times and made into a foam in the developer supply tank 44a, the solution was supplied onto the photosensitive lithographic printing plate surface through the developer supply slit 6. In addition, SDP-12 (
A developer for positive-type photosensitive planographic printing plates (manufactured by Konica Corporation) was charged, and the developer was mixed with water in the developer mixing tank 42b.
After being diluted twice and made into a foam in the developer tank 44b, it was supplied onto the photosensitive lithographic printing plate surface through the developer supply slit 6.

[0058] Add 15 liters of water to the rinse water tank 21 and rinse.
The gum liquid tank 31 was charged with 10 liters of SGW-2 (manufactured by Konica Corporation, gum liquid) diluted twice with water.

The temperature of the preheat roller 4 was adjusted to 40° C., and the temperature of the developer was adjusted to 27° C. inside the developer supply slit 6 using a heater (not shown). Further, the transport speed of the photosensitive planographic printing plate was adjusted so that the development time was 20 seconds.

As the developer, SDN-21 was supplied when processing a negative photosensitive lithographic printing plate, and SDP-12 was supplied when processing a positive photosensitive lithographic printing plate. Further, the amount of developer supplied was 100 ml per 1 m 2 of the photosensitive planographic printing plate to be processed.

Under these conditions, the positive photosensitive lithographic printing plate and the negative photosensitive lithographic printing plate 1003 mm×
After processing a large number of 800mm pieces one by one,
A high quality printing plate was obtained which was uniformly developed on both the front and back sides.

Example 2 SD-32 (manufactured by Konica Corporation, a common negative/positive developer) is charged into a concentrated developer tank 40a, diluted six times with water in a developer mixing tank 42a, and then transferred to a developer supply tank. 44a, the foam is supplied to the photosensitive lithographic printing plate surface to be processed, and the operation of the metering pump 47b is stopped, and the negative-working photosensitive lithographic printing plate and the positive-working photosensitive lithographic printing plate are supplied. When the same experiment as in Example 1 was conducted except that the plates were developed with the same developer, the same results as in Example 1 were obtained.

Embodiment 3 The concentrated developer tank 42a of the automatic processor shown in FIG.
D-32 is charged, diluted six times with water in the developer mixing tank 42a, made into a foam in the developer supply tank 44a, and then sent to the developer tank 80 to be supplied to the photosensitive lithographic printing plate surface. I made it. The developer, which has returned to a liquid state through defoaming, is returned to the developer supply tank 44a from the bottom of the developer tank 80 and is reused. Also,
The amount of developer supplied was 100 ml per m2 of photosensitive lithographic printing plate to be processed.

The temperature of the preheat roller 4 was adjusted to 40° C., and the temperature of the developer was adjusted to 27° C. inside the developing tank 80 using a heater (not shown). Further, the transport speed of the photosensitive planographic printing plate was adjusted so that the development time was 20 seconds.

Under these conditions, in the same manner as in Example 1, a large number of positive-working photosensitive planographic printing plates and negative-working photosensitive planographic printing plates of 1003 mm x 800 mm were alternately developed and washed one by one. , treated with gum solution. As a result, the same results as in Example 1 were obtained.

Example 4 An experiment similar to Example 1 was conducted using the automatic developing machine shown in FIG. Results similar to those in Example 1 were obtained.

Comparative Example 1 Concentrated developer tank 40 of an automatic processor shown in FIG. 4(a)
Pour SDN-21 into a and developer mixing tank 4.
2a, the developer is diluted 6 times with water, and the developer is supplied to the developer supply nozzle 1.
00a and 100b were supplied in liquid form onto the photosensitive lithographic printing plate surface. Further, SDP-12 was charged in the concentrated developer tank 40b, diluted six times with water in the developer mixing tank 42b, and supplied in liquid form onto the photosensitive lithographic printing plate surface by the developer supply nozzle 100. . FIG. 4(B) is a sectional view of the developer supply nozzle 100 in FIG.

The temperature of the preheat roller 4 was adjusted to 40° C., and the temperature of the developer was adjusted to 27° C. inside the developer supply nozzle using a heater (not shown). Further, the transport speed of the photosensitive planographic printing plate was adjusted so that the development time was 20 seconds.

The amount of developer supplied was set to 100 ml/m2 per 1 m2 of the photosensitive lithographic printing plate to be processed, and as in Example 1, the above-mentioned positive-working photosensitive lithographic printing plate and negative-working photosensitive lithographic printing plate were 1003 mm When a large number of 800 mm plates were alternately developed, washed with water, and treated with a gum solution, all plates suffered from partial development defects.

Comparative Example 2 An experiment similar to Comparative Example 1 was carried out except that the amount of developer supplied was 200 ml/m 2 per 1 m 2 of the photosensitive planographic printing plate to be processed. As a result, the developer supplied to the back side of the photosensitive lithographic printing plate dripped down, making it impossible to uniformly develop the entire surface.

[0071]

Effects of the Invention According to the present invention, negative-working photosensitive lithographic printing plates and positive-working photosensitive lithographic printing plates can be processed economically and stably from beginning to end with the same automatic developing machine, and both sides can be processed stably from beginning to end. Both sides of the plate can be stably developed.

[Brief explanation of the drawing]

Figures 1, 2, and 3 are schematic sectional views showing examples of processing equipment for carrying out the method of the present invention, and Figures 4 (a) and (b) are schematic sectional views of processing equipment used in comparative examples. FIG.

[Explanation of symbols]

1.Developing section 2. Washing section 3. Rinse/gum part 4. Preheat roller 5.Developer supply slit 40a‥Concentrated developer tank ４１‥Dilution water tank 44a, 44b...Developer supply tank 52‥Air tank 53‥Compressor 80‥Developing tank 90a, 90b... Foaming spray nozzle S‥Transport path

Claims (2)

[Claims] Claim 1. A method for processing a photosensitive lithographic printing plate, in which a negative photosensitive lithographic printing plate and a positive photosensitive lithographic printing plate are transported and developed in an arbitrary order using the same automatic developing machine, A photosensitive planographic printing plate 1 that is processed by foaming a substantially unused negative/positive common developer or a special developer depending on the type for each photosensitive planographic printing plate to be processed.
A method for processing a photosensitive lithographic printing plate, characterized in that 10 to 200 ml per m2 is supplied for development. 2. The processing method according to claim 1, wherein the developer contains a surfactant.