JPH03200971A - Processing method for photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To obtain the printing plate which is free from staining at the time of printing by providing paired rollers under a development accelerating means and immersing the paired rollers and the squeezing roller on the lower side into a tank for holding a developing soln. CONSTITUTION:A PS plate, the surface to be processed is faced upward, is transported from the left to the right of Fig. by transporting rollers 1, etc. and the unused developing soln. is developing soln. supplying member 4. The PS plate coated with the developing soln. is transported in such a posture that the film of the developing soln. applied thereon is held on the surface; thereafter, the PS plate is immersed into the developing soln. in a developing tank 10. The surface of the PS plate is then rubbed by a brush roller 7 which is the development accelerating means and thereafter, the developing soln., eluted components, etc., sticking to the surface of the PS plate are removed by squeezing rollers 8. Since lower part of the roller 9 provided below the development accelerating means is so constituted as to be immersed in the developing soln., the contamination of the development accelerating means and the squeezing roller is prevented. The printing plate which is free from the staining at the time of printing is obtd. in this way.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a photosensitive lithographic printing plate (hereinafter referred to as 115th plate).
The present invention relates to a developing method, that is, a processing method and processing apparatus for imagewise dissolving a layer on a support of an imagewise exposed PS plate.

[Conventional technology]

Conventionally, automatic developing machines have generally been used for developing PS plates. When processing an exposed 15th plate using an automatic processor, there are two methods: spraying developer onto the plate surface in a shower or spray while transporting the PS plate horizontally, or placing the PS plate in a processing tank containing a large amount of developer. A method has been used in which the material is immersed while being transported in a curved manner. Furthermore, since a large amount of developer is required, the developer has been recycled and reused in consideration of economical efficiency.

In this case, in order to recover from fatigue of the developer due to processing and carbon dioxide gas in the air, a method has been used to keep the development process stable by replenishing a developer replenisher.

However, even if such a replenishment method is adopted, although the frequency of solution replacement is reduced, the need for replacement remains, and fluctuations in the activity of the developer cannot be sufficiently controlled.

JP-A No. 63-71855 discloses a PS plate processing method that does not require such troublesome developer management and can stably process a wide variety of PS plates without requiring a complicated and expensive replenishment device. After supplying substantially virgin developer to the surface of the PS plate to be processed, as shown in
A PS plate processing device has been put into practical use that performs development processing by immersing the plate in a tank that holds a repeatedly used developer, then passing it through a development accelerator, and then passing it through a pair of upper and lower squeezing rollers.

In this processing device, in order to prevent the development accelerator and the squeeze roller from getting dirty, used developer is supplied to the development accelerator and the squeeze roller through a shower nozzle to clean them. . However, in this method, the precipitates formed in the used developer adhere to the development accelerator and the squeezing roller through the shower nozzle, and are transferred to the surface of the PS plate being transported. There is a problem that stains occur. Furthermore, since the used developer is circulated using a pump, the pump, piping, shower nozzle, etc. are likely to become clogged, and there is a problem in that these must be cleaned frequently.

JP-A-1-185633 has the above-mentioned JP-A-1-185633.
In order to avoid stains on the printing plate due to drying of development promoting members such as brush rollers and sponge rollers in the developing device described in Publication No. 71855, which supplies a relatively small amount of developing solution to the PS plate for development, a setting is made below the development promoting member. discloses a means for preventing the development accelerating member from drying and staining the printing plate by immersing a roller that rotates in contact with the development accelerating member in a developer. It cannot be said that the drying prevention effect is sufficient.

[Problem that the invention seeks to solve]

The present invention solves various problems in the processing method.
It is an object of the present invention to provide a method for processing an S plate, and an object of the present invention is to provide a PS plate that can prevent stains on the development accelerator and the squeezing roller and obtain a printing plate that does not cause background stains during printing.
The purpose is to provide a method for processing plates. Another object of the present invention is to provide a PS plate processing method that eliminates the trouble of cleaning the shower nozzle, pump, piping, etc. for cleaning the development accelerator and the squeezing roller, and can improve work efficiency. It is.

[Structure of the invention]

The object of the present invention is to process 1 using an automatic processor.
After supplying a substantially unused developer to the plate surface for each 8th plate, the PS plate is immersed in the repeatedly used developer, guided through a development accelerator, and then passed through a pair of upper and lower plates. A PS plate processing method in which a development process is performed by passing the PS plate through a squeeze roller, characterized in that the roller provided below the development accelerator and the lower squeeze roller are immersed in a tank holding a developer. This is achieved through a processing method.

The above-mentioned object of the present invention is to provide the above-mentioned processing method, in which the development accelerator, the counter roller and the lower squeezing roller are constantly rotated or rotated at regular intervals while transport of the PS plate is interrupted. This is better achieved by keeping the

The method of the present invention will be explained below with reference to the drawings of the apparatus used in the method.

FIG. 1 is a schematic sectional view showing an example of a processing apparatus used in the method of the present invention. In the figure, reference numeral 4 denotes a developer supplying member that supplies substantially unused developer to the plate surface for each 18th printing plate. IO is a developer tank in which the PS plate is immersed in a developer solution that is used repeatedly. 7 is a development accelerating means, and in this example, a brush roller is used. 8 is a squeeze roller;
26 is a tank that holds the developer (hereinafter referred to as "immersion tank")
, ps is the transportation path of the PS plate.

First, the PS plate is transported from the left to the right in the figure using the transport roller 1 with the side to be treated facing up, and an unused developer is uniformly applied to the surface of the PS plate via the developer supply member 4. do.

The PS plate coated with the developer is transported in such a position that the coated developer film is held on the surface, and then immersed in the developer in the developer tank IO. This immersion is to prevent insufficient development from occurring at the peripheral edge of the PS plate.

The surface of the PS plate is then rubbed by a brush roller 7, which is a development accelerator, and then a squeezing roller 8 removes the developer, eluted components, etc. adhering to the surface of the PS plate. As the brush roller 7, for example, a pipe made of vinyl chloride resin with a diameter of about 50 mm is used, in which nylon bristles with a diameter of about 0.05 to 1.0 mm are implanted to a length of 10 to 20 mm.

The development promoting means is not limited to a brush roller, but also includes a method of rubbing by rotating a flat rubbing member, a method of rubbing by sliding a flat rubbing member back and forth and/or left and right, and a method using a brush roller. In this case, a method of swinging back and forth and/or left and right while rotating can be used. A plurality of these rubbing members may be used in combination.

These rubbing members can be created using, for example, brushes, sponges, cloth, or the like.

Other development accelerating means include, for example, a method of blowing high-pressure air, a method of irradiating ultrasonic waves, and JP-A-58-4204.
A method of electrochemical development as described in No. 2, a method of instantaneously heating the developer on the PS plate by microwave irradiation, or a method of honing the plate surface using a processing solution containing abrasive powder. Examples include methods.

In the present invention, a roller for supporting and conveying the PS plate is provided below the development promoting means, a tank containing a developer is provided so that the lower part of the roller is immersed in the developer, and the roller is rotated. Further, a tank containing a developer is provided so that the lower part of the lower roller constituting the squeezing roller is immersed in the developer.

This immersion keeps the roller and the squeezing roller constantly wet, and they carry the developer to the development accelerator (for example a brush roller) and the upper squeezing roller, which also stay wet. Therefore, components of the developer, components of the PS plate dissolved in the developer, and precipitates generated in the developer adhere to each roller and development accelerator, dry, and are transferred to the plate surface. It is possible to prevent printing stains from occurring. Therefore, it is preferable to keep these rotating even when the conveyance of the PS plate is interrupted, from the viewpoint of stain prevention effect.

For example, the roller 9 and the squeezing roller 8 have hardness (JI
S-A) Rubber material with a hardness of 30 to 60 and a resilience of 50% or more, such as silicone rubber (hardness of 40, resilience of 70%)
%), in-prene rubber (hardness 50, anti-bacterial elasticity 80%)
, styrene rubber, butadiene rubber, chloroprene rubber,
Those using urethane rubber, urethane-propylene rubber, etc. can be used.

In the present invention, the means for supplying a substantially unused developer to the plate surface of the PS plate for each 15th edition, the means for immersing the PS plate in a repeatedly used developer, the means for accelerating development, etc. are limited to those described above. However, any method including known methods can be used.

In the present invention, the tanks for immersing the roller provided below the development accelerator and the lower squeezing roller in the developer may be provided separately, or may be configured in one common tank. 1st
26 in the figure is a relatively shallow tank with a relatively small amount of developer, and is disposed of together with the developer in the developer tank IO at the end of a day's work, for example.

FIG. 2 is a sectional view showing another example of the processing apparatus used in the method of the present invention. In this example, the tank 26 that holds the developer
The tank a has a relatively deep depth and a capacity of 3 to 5a, so that even if a precipitate is formed, it will not accumulate at the bottom of the tank 26m and will not adhere to the roller 9 and squeezing roller 8. The developer can be replaced, for example, once every 1 to 2 weeks without replacing it every day.

FIG. 3 is a sectional view showing still another aspect of the processing apparatus used in the method of the present invention. In this example, a tank 26b for holding a developer and a developer tank 10 are connected, and - enters the tank 26b. Tank 26b
The developer tank 10 is constructed to be shallow like the tank 26 in FIG. 1, and the developer in the developer tank IO and the developer in the tank 26b are renewed, for example, every day before the start of work. In addition, in each drawing, *1, *11, *2, and *2
, *3 and *3 are connected by piping, respectively.

In the development process according to the present invention, a substantially unused developer is first supplied to the PS plate. Here, the practically unused developer is not an unused developer. It also refers to an unused developer and one with a developing ability that is better than practical. The developing solution used in the present invention may be one suitable for the PS plate to be processed, and the post-treatment of the PS plate subjected to the development process according to the present invention may be carried out in accordance with a conventional method.

The PS plate processed by the method of the present invention is of the type that is imaged by dissolution, and for example, in addition to the so-called negative type and positive type 15 plates, there is also a type in which a resist layer is formed in an imagewise manner by an electrophotographic method. Included are those having a layer on the plate material of the lithographic printing plate that is soluble in the developer to be obtained.

Next, preferred embodiments of the present invention will be listed.

(2) The dipping tank in which the roller and lower squeezing roller provided below the development accelerator are immersed is a shallow vat, and the developer inside is replaced once every 1 to 14 days.

(2) The capacity of the above bat is 1-1 OQ.

(2) The automatic developing machine according to the present invention has means for supplying unused developer to the immersion tank.

■ Place a squeegee plate on the lower roller (in the developer)
Scrape off any dirt that may adhere to the roller.

■The development accelerator is a brush roller.

〔Example〕

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

Example 1 A concentrated developer having the composition shown below was charged into the concentrated developer tank 14 of the automatic processor shown in FIG.

Pure water 430 parts by weight Benzyl alcohol to weight s Benzoic acid 80 parts by weight 50% aqueous sodium hydroxide solution 200 parts by weight Emulgen 147
3 parts by weight (manufactured by Kao Corporation, nonionic surfactant) Sodium silicate aqueous solution 200 parts by weight (JIS standard sodium silicate No. 3) 40% sodium sulfite aqueous solution 300 parts by weight Also, 1512 parts by weight of water was added to the washing water tank 20. Gum liquid tank 21
1Off of the following Iii gum solution was added to the tank.

Gum arabic 5 parts by weight Dextrin 15 parts by weight Phosphoric acid (75%) 0
．． 3 parts by weight Water 80 parts by weight Sea 2-
Sodium ethylhexyl sulfosuccinate 1.0 parts by weight Nonylphenol polyethylene oxide ether (6 moles of ethylene oxide) 1.0 parts by weight Stearic acid 1.0 parts by weight Sorbitan monooleate 1.0 parts by weight Dibutyl phthalate 2.0 parts by weight Set the conveyance speed of the automatic developing machine so that the development time is 20 seconds, and create a negative PS plate SWN and a positive PS plate S.
MP-N (all made by Konica Corporation: SMP-N only 2
A sample having a size of 10010O3800 mm (exposure for 40 seconds from a distance of 60 cm using a kW metal halide lamp) was treated at a ratio of 1:1. Note that the concentrated developer is diluted six times with water in the developer mixing tank 12,
The developer is supplied onto the 13th printing plate via the developer supply member 4. The amount of developer supplied was 200 mff1 per m2 of PS plate, and the temperature of the developer was set to 27° C. in the developer supply member 4 and the developer tank IO. Further, the immersion tank 26 was charged with IQ of the above-mentioned concentrated developer diluted 6 times with water. The developer solution and washing water in the immersion tank were replaced every day. In addition, the brush roller 7 and the brush guide roller 9
The squeezing roller 8 is kept rotating even when transport of the PS plate is interrupted.

The PS plate was processed under these conditions for 1 month at a rate of 100 plates per day, but no foreign matter was observed on the treated plate. In addition, 5PO-1 (Konica Corporation) is printed on the printing plate.
I tried adding some development ink (manufactured by J.D. Co., Ltd.), but it did not cause any stains.

Comparative Example 1 An experiment similar to Example 1 was conducted using the automatic developing machine shown in FIG. However, in this automatic developing machine, instead of immersing each roller in a full developer solution in the immersion tank, the developer tank 29 is filled with a concentrated developer solution diluted six times with water. Add 5Q of the developer solution and use Shower Vibe 3.
0 to the brush roller 7 and the brush guide roller 9,
It was supplied to the squeezing roller 8 and cleaned. Developer tank l
The over 70-degree developer and the developer squeezed out by the squeezing roller 8 enter the developer tank 29, from which the over-70 developer is discarded. The developer in the developer tank 29 was not replaced during the process.

When a PS plate was processed in the same manner as in Example 1 under these conditions, the shower pipe 30 became clogged in the first week, and if the inside of the pipe was not cleaned, the processed plate would become stained and the developing process would be delayed. I couldn't continue. Furthermore, 2
After a week, the shower pipe 30 became clogged again, so an attempt was made to clean the inside of the pipe and continue the process, but the sediment that had formed inside the developer tank 29
0 to the brush roller 7 and squeeze roller 8,
Since it was transferred to the surface of the PS plate and became a stain, it was necessary to replace the developer in the developer tank 29 with a new one. When processing was continued further, developing section 1 was removed in the first month.
Due to hard deposits attached to the inside of the pump 25 in No. 6,
The pump has stopped working.

Example 2 An experiment similar to Example 1 was conducted using the automatic developing machine shown in FIG. However, the immersion tank has a capacity of 5Q (2
6a) was used, and the developing solution inside was replaced once a week. Results similar to those in Example 1 were obtained.

Example 3 In the automatic developing machine shown in Fig. 3, a concentrated developer with the composition shown below was used, and the PS plate to be processed was SM.
An experiment similar to Example 1 was conducted except that only PN was used.

Concentrated developer composition Pure water 600 parts by weight Benzoic acid 100 parts by weight 50%
Sodium hydroxide aqueous solution 250 parts by weight Emulgen 1475 parts by weight (manufactured by Kao Corporation, nonionic surfactant) Sodium silicate aqueous solution 150 parts by weight (JIS standard sodium silicate No. 3) Results similar to those in Example 1 were obtained. .

Example 4 An experiment similar to Example 1 was conducted except that the brush roller 7 and brush guide roller 9 were rotated for 10 seconds every 5 minutes while transport of the PS plate was interrupted. Results similar to those in Example 1 were obtained.

Example 5 An experiment similar to Example 2 was conducted except that the brush roller 7 and brush guide roller 9 were rotated for 30 seconds every 10 minutes while transport of the PS plate was interrupted. Similar results as in Example 2 were obtained.

Example 6 An experiment similar to Example 3 was conducted except that the brush roller 7 and the brush guide roller 9 were rotated for 20 seconds every 5 minutes while transport of the PS plate was interrupted. Similar results to Example 3 were obtained.

〔Effect of the invention〕

According to the present invention, using an automatic developing machine, after supplying a substantially unused developer to the plate surface for each 15-plate plate, the plate is immersed in the developer to be used repeatedly, and then a development accelerator is applied. In the processing method in which the development accelerator and the aperture roller are passed through the processing method, the development accelerator and the aperture roller are prevented from being smeared, thereby making it possible to obtain a printing plate that does not cause background smear during printing. It is no longer necessary to clean the shear nozzle, pump, piping, etc. for cleaning, increasing work efficiency.

[Brief explanation of drawings]

FIGS. 1, 2, and 3 are schematic sectional views showing an example of an apparatus used in the method of the present invention, and FIG. 4 is a schematic sectional view of an apparatus used in a comparative example. 1.17...Conveyance roller 2...Press roller 3...Developer supply pipe 4...Developer supply member 5...Roller 6
... Guide roller 7 ... Brush roller 8.18 ... Squeezing roller 9 ... Brush guide roller lO ... Developer tank 11 ... Developer supply tank 12 ... Developer mixing tank 13. ... Solenoid valve 14 ... Concentrated developer tank 15 ... Dilution water tank 16 ... Developing section 19.
30... Shower pipe 20... Rinsing water 22... Rinsing section 24... Metering pump 26.26a, 26b - Soaking tank 28... Squeegee plate PS... Conveyance path Gum liquid Gum pulling section pump cock developer tank

Claims (2)

[Claims] (1) Using an automatic developing machine, a substantially unused developer is supplied to the plate surface for each photosensitive lithographic printing plate to be processed, and then the developer is used repeatedly for the photosensitive lithographic printing plate. 1, then passed through a development accelerator, and then 1
In a method for processing a photosensitive lithographic printing plate in which a development process is performed by passing the plate through a pair of squeezing rollers, a pair of rollers is provided below the development promoting means, and the pair of rollers and the lower squeezing roller are placed in a tank that holds a developer. A method for processing a photosensitive lithographic printing plate, characterized by immersion. (2) Claim (1) characterized in that the development accelerator, the pair of rollers, and the lower aperture roller are rotated constantly or rotated at regular intervals while conveyance of the photosensitive planographic printing plate is interrupted. ) Processing method described