JPH03289663A - Processing method and processing device for photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To prevent the transfer of the precipitate generated in a used developing soln. to the surface of a photosensitive planographic printing plate by supplying the substantially unused developing soln. to a development accelerating means while the processing of the photosensitive planographic printing plate is held interrupted. CONSTITUTION:After the photosensitive planographic printing plate (PS plate) emerges from a developing tank 8, the surface thereof is rubbed by a develop ment accelerating means 10 consisting of a brush roller. The mixture of the developing soln. sticking to the surface of the PS plate and the eluate from the PS plate are removed by squeezing rollers 15a, 15b. The development acceler ating means 10 supplies the substantially unused developing soln. while this means is kept operated at all times or intermittently while the processing of the PS plate is interrupted, by which drying is prevented and stains are washed away. The problems that the precipitate contg. the used developing soln. generat ed in the case of washing with the used developing soln. and the generation of staining in printing by the transfer of this precipitate to the PS plate are eliminated 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 148 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 PS plate with an automatic processor, there are two methods: spraying developer onto the plate surface in the form of a shower or spray while transporting the PS plate horizontally, or placing the 23 plate in a processing tank containing a large amount of developer. A method has been used in which the material is transported in a curved manner and then immersed. 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 drying of the development accelerating member and the like and preventing staining of the printing plate by immersing a roller rotating in contact with the development accelerating member in a developing solution. There is no mention of rotating these while the process is interrupted, and it cannot be said that the effect of preventing the development promoting member from drying is sufficient.

[Purpose of the invention]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method and apparatus for processing a photosensitive lithographic printing plate, which prevents deposits formed in a used developer from being transferred to the surface of a PS plate.

Another object of the present invention is to provide a PS plate processing method and processing apparatus that eliminates the hassle of cleaning pumps, piping, shower nozzles, etc. and improves workability.

Still another object of the present invention is to provide an improved means for preventing printing stains caused by a processing liquid adhering to a development promoting member etc. during development processing, drying and being transferred to a PS plate.

[Structure of the invention]

The above objects of the present invention are achieved by the following processing method and processing apparatus.

In the processing method of the present invention, a developing solution is supplied to the plate surface of the PS plate to be processed, and after passing through a development accelerator, a pair of upper and lower squeezing rollers are immersed in a dipping tank in which the lower squeezing roller holds the developing solution. A method for processing a PS plate in which development processing is performed by passing the plate through a squeeze roller is characterized in that substantially unused developer is supplied to the development accelerator while processing of the PS plate is interrupted.

The processing apparatus of the present invention includes means for automatically conveying the PS plate while supplying a developer onto the plate surface of the PS plate, a development accelerator, a pair of rollers provided below it so as to be in contact with the development accelerator, and upper and lower rollers. In a PS plate processing apparatus having means for passing a squeeze roller consisting of a pair of rollers, means for supplying substantially unused developer to the development promoting means while processing of the PS plate is interrupted; The present invention is characterized by having means for immersing the pair of rollers and the lower squeezing roller of the squeezing roller in a developer.

In this specification, "while the processing of the rPS plate is suspended" means that the automatic developing machine that processes the PS plate is turned on, and the automatic developing machine processes the PS plate normally at any time. In other words, the temperature of the developer is adjusted to a predetermined temperature.

The present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing an example of an automatic developing machine having a processing apparatus according to the present invention. In the figure, 1 is a developing section for performing development, 20 is a washing section, and 30 is a rinsing gum section for performing treatment with a rinsing liquid or desensitizing treatment.

In the developing section 1, reference numeral 2 denotes a conveyance roller, a developer supplying member that supplies developer to the plate surface for each 3-PS plate, and has a slit formed by two plates at its lower end. Pour the developer to a uniform thickness over the transport width.
It is configured to be supplied to the surface of the S plate, and for details, refer to Japanese Patent Laid-Open No. 64-81943. 4 supports and transports the PS plate being transported from below, and also
When the plate does not pass through, it is a developing roller that comes into sliding contact with the lower end of the developer supply member 3, that is, the slit portion, and forms a developer reservoir in this sliding contact portion. 5a is a receiver for receiving and reusing the developer which has flowed downward without being substantially used for development when supplied from the developer supply member 3; 6 is a receiver for mixing the concentrated developer and dilution water; 7 is a developer tank into which the developer prepared in the mixing tank 6 is placed.

8 is a developing tank for performing immersion development, and 9 is a port into the developing tank 8.
A guide roller that guides the S plate, 1O is a development accelerator consisting of a brush roller, and 11 is a guide roller that guides the S plate,
A brush guide roller 13 supports and conveys the S plate, and 13 is a shower nozzle, which is used to supply substantially unused developer to the development accelerator 1O, so that the developer in the developer tank 7 is sent. It has become. 14 is a cover 15a that covers the development promoting means 10; 15b is a squeezing roller; 16
1 is an immersion tank for immersing the brush guide roller 11 and the lower squeezing roller 15b in the developer; 17 is a liquid guide plate that guides the overflow of the developer in the developer tank 8 to the immersion tank 16;
8 is a pipe that leads the over 70- of the immersion tank 16 to a waste liquid tank (not shown), 19a, 19b, and 19c are metering pumps, and P is a transport path for the PS plate. In the figure, *l and *l
, *2 and *2, *3 and *3, etc. are connected by piping.

When using a brush roller as the development accelerator lO,
For example, a pipe made of vinyl chloride resin with a diameter of about 501 m, in which nylon bristles with a diameter of about 0.05 to 1.0 mm are implanted to a hair length of lO to 20+++i, is used.

The development accelerating means in the present invention physically rubs the plate surface with a rubbing member such as a brush or sponge,
In addition to the brush roller shown in Fig. 1, there are methods of rubbing by rotating a flat rubbing member, methods of rubbing by sliding a flat rubbing member back and forth and/or left and right, and brush rollers. When used, 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.

The lower nozzle 13 may be a pipe-shaped member having a plurality of nozzle holes that can supply substantially unused developer to the entire width of the development accelerator in the transport width direction, for example, with an inner diameter of l.
It is possible to use a pipe having a diameter of 1 to 3 mm and provided at intervals of 5 to 20 mm on the side surface of a pipe of about 3 cm. The means for supplying substantially unused developer to the development accelerator is not limited to the shower nozzle, but any arbitrary means can be used.

Regarding the supply timing of the developer, it is most desirable to supply the developer at all times from the viewpoint of cleaning the development accelerator, but considering economic efficiency, it is preferable to supply the developer for 3-60 minutes (more preferably It is appropriate to supply the liquid for 10 to 60 seconds at intervals of 5 to 30 minutes. The appropriate amount of developer to be supplied at one time is in the range of 1O to 500IIIQ per conveyance width direction 1a.

The development accelerating means IO is
When it comes into contact with the developer supplied to the plate surface of the S plate, it is sufficiently wetted and does not dry out. Therefore, P.S.
The supply of substantially unused developer to the development accelerator 10 can be omitted while the plate is being processed. The depth of the immersion tank 16 is such that the distance between the lowest part of the lower squeezing roller 15b and the bottom of the immersion tank 16 is 1 cm or more, so that the solids in the developer in the tank are not precipitated to the bottom of the nuclide. This is preferred from the standpoint of reducing the amount of solids in the surface liquid. Squeezing roller 15a%
15b and the brush guide roller 11 that are commonly used can be used.

In the washing section 20, 21 is a washing water tank, 23 is a shower nozzle, and 42a is a pump. Rinse ◆ In the gum part, 31 is a rinser that contains a rinse liquid or a desensitizing liquid.
A gum liquid tank, 33 is a shower nozzle, and 42b is a pump.

The processing device of the present invention, while interrupting the processing of the PS version,
It is desirable to have a mechanism for intermittently operating the development accelerator and the squeezing roller at arbitrary time intervals, and a mechanism for supplying substantially unused developer to the development accelerator in conjunction with the operation.

Next, the operation of the apparatus of the present invention and the method of the present invention will be explained based on FIG.

First, when the PS plate is inserted from the left end of the apparatus with the side to be processed facing up, the 13th plate detection switch (not shown) rotates the conveyance roller 2, etc., and moves the PS plate to the right in the figure. transport. Further, the operation of the pump 19b is controlled by a control mechanism (not shown) so that a predetermined amount of developer is supplied from the developer supply member 3 onto the plate surface of the PS plate for a predetermined period of time.

In this way, substantially unused developer is uniformly applied from the developer supply member 3 to the plate surface of the PS plate.

The PS plate coated with the developer is then guided into the developer tank 8 by guide rollers 9 and immersed in the developer in the developer tank 8 . This immersion is to prevent insufficient development from occurring at the peripheral edge of the PS plate. The developer in the developer tank 8 is replenished by the inflow of the developer applied by the developer supply member 3 and held on the PS plate, and by feeding the developer in the receiver 5a with the pump 19c. .

After the PS plate comes out of the developer tank 8, the plate surface is rubbed by a development accelerator lO consisting of a brush roller, and then the developer attached to the surface of the PS plate and eluates from the PS plate are removed by squeezing rollers 15a and 15b. A mixture of is removed. The developer in the immersion tank I6 is replenished and renewed with the developer from the shower nozzle 13 and the overflow of the developer tank 8. The overflow of the developer in the immersion tank 16 enters a waste liquid tank (not shown) via a pipe 18. The development accelerator lO is PS
Drying is prevented and dirt is washed away by supplying substantially unused developer while operating constantly or intermittently during interruptions in plate processing. Squeezing roller 15
a and 15b are also operated constantly or intermittently, and are prevented from drying and cleaned of dirt by the developer in the dipping tank 16 carried by the lower squeezing roller 15b.

Figure f$2 is a sectional view showing another embodiment of an automatic developing machine having a processing device according to the present invention. In the example shown in the figure, the developer in the receiver 5b, which receives the developer supplied from the developer supply member 3 onto the 13th plate and flowed down without being substantially used for development, is transferred to the development accelerator 10. The developer is sent to the shower nozzle 13 for use as a cleaning developer.

In the present invention, since the development accelerating means is washed with substantially unused developer, the precipitate contained in the used developer that is generated when washing with the used developer adheres to the 23rd plate. This eliminates the problem of smudges caused by transfer to the paper. Here, the term "substantially unused developer" refers to a developer which is not an unused developer but can still provide the effects of the present invention, such as practical improvements, as compared to an unused developer.

In addition, since the lower roller of the squeezing roller is immersed in the developer, it does not dry out during the operation of the processing device, and the processing liquid adheres to the surface of the squeezing roller and dries to form a fixed substance, which can cause the PS plate to dry. This prevents the printing from being transferred to the surface and causing printing stains.

In the processing method of the present invention, a brush roller is used as the development accelerating means, and while the processing of the PS plate is interrupted, the brush roller 10 and squeeze rollers 15a and 15b are constantly rotated or the processing liquid attached to them is It is preferable to rotate intermittently at least at time intervals that do not cause drying.

In the present invention, there are no restrictions on the means for supplying a developer to the plate surface of the PS plate and the means for developing the PS plate by immersing it in a repeatedly used developer, and any means including the above-mentioned means can be adopted. .

Further, in the present invention, in addition to the development promotion means, other development promotion means, such as a method of blowing high pressure air,
A method of irradiating ultrasonic waves, a method of electrochemical development as described in JP-A No. 58-42042, a method of instantaneously heating the developer on the PS plate by irradiation of microwaves, or a polishing agent. It is optional to add a method of honing the plate surface using a processing liquid containing powder.

The developer used in the present invention may be one that is suitable for the PS plate to be processed. In addition, post-treatment of the PS plate subjected to the development treatment according to the present invention (washing with water, treatment with a rinsing liquid,
Desensitization treatment, etc.) can be carried out according to a conventional method.

A photosensitive lithographic printing plate suitable for applying the present invention is one that undergoes elution type development, and is a photosensitive material that has a photosensitive layer on a support whose solubility in a developer changes upon irradiation with light, such as a negative type photosensitive material. Also included are positive-working PS plates, and printing materials having on a support a layer soluble in a developer on which an image-like resist layer is formed by an electrophotographic method or the like.

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

■The pair of upper and lower squeezing rollers immersed in the dipping tank are kept rotating at all times.

■Use a brush roller as a development accelerator.

- The brush roller is kept rotating constantly or rotated at regular intervals while processing of the PS plate is interrupted.

■ Pour the over 70-mL solution from the developer tank into the immersion tank.

■The distance between the bottom end of the lower squeezing roller and the bottom of the dipping tank is lam.
The above shall apply.

■ 3 to 60 minutes, more preferably 5 to 30 minutes as a development accelerator
Provides substantially unused developer solution every minute.

[Effect]

According to the present invention, in the processing method of supplying a developer to a PS plate and developing it, a substantially unused developer is used as the developer supplied to the development accelerator and washed, so that it is possible to use a substantially unused developer to clean the PS plate. This eliminates clogging of the pump, piping, shower nostle, etc. in the liquid delivery route that circulates the developer, which occurs when using a used developer containing eluates from the developer. The developer containing the components eluted from the PS plate adheres to the development accelerator and dries up, causing the PS plate to dry up.
The defect of printing stains caused by transfer to the plate surface is improved. Furthermore, compared to known means in which the lower roller of the development accelerator is immersed in the developer, the present invention provides a cleaning effect by directly supplying substantially unused developer to the development accelerator. This has a large effect in preventing a developer containing eluates from the PS plate from adhering to the development accelerator, drying, and transferring to the PS plate, resulting in printing stains.

〔Example〕

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

Example 1 In the automatic developing machine shown in FIG.
Using D-32 (manufactured by Konica Corporation, common developer for negative and positive), it is diluted six times with water in the developer mixing tank 6 and supplied to the 23rd plate surface to be processed via the developer supply member 3. I made it so that it would be done.

In addition, 5D-
32 diluted 6 times with water was prepared. The developer temperature is adjusted to 27° C. inside the developer supply member 3 and the developer tank 8, and the transport speed of the PS plate is adjusted so that the developer is supplied to the plate surface by the developer supply member 3, and then the squeeze roller 15a , the time it takes to reach 15b was set to 20 seconds. In addition, the brush roller IO, brush guide roller 11, and squeeze rollers 15a and 15b are PS
It keeps rotating even when plate processing is interrupted,
100 mff of developing solution was supplied from the new solution supply nozzle 14 to the brush roller 10 every 10 minutes.

The rinsing water tank 21 was filled with 15 Q of water, and the rinsing gum liquid tank 31 was filled with 104 ml of 5GW-2 (gum liquid manufactured by Konica Corporation) diluted twice with water.

Under these conditions, the l0
03a+mX800mm 100 in l:l ratio
The plates were continuously processed, and 100 plates were processed again after 1 hour, or no stains on the PS plate surface were observed. Also, 1
The offset printing was performed using the 01st edition, the 00th edition, or the 0th edition, or a good printed matter with no stains was obtained.

Example 2 Brush roller lO and brush guide roller 11 are set to PS
An experiment similar to Example 1 was conducted except that the plate was rotated for 10 seconds every 10 minutes while processing of the plate was interrupted.

The same results as in Example 1 were obtained.

Example 3 An experiment similar to Example 1 was conducted except that the automatic developing machine shown in FIG. 2 was used. Results similar to those in Example 1 were obtained.

Example 4 An experiment similar to Example 2 was conducted except that the automatic developing machine shown in FIG. 2 was used. Similar results as in Example 2 were obtained.

Comparative Example Using the automatic developing machine shown in Fig. 3, which has a structure in which the cleaning mechanism for the development promoting means is removed from the processing apparatus shown in Fig. 1,
An experiment similar to Example 1 was conducted except that the brush roller 5, squeeze roller 9, and brush guide roller 13 were stopped while processing of the PS plate was interrupted.

The results show that among the 101st edition 0 and 200th edition 0 treated editions,
The surface of the 10th edition was smudged.

〔Effect of the invention〕

According to the present invention, in a processing method using an automatic developing machine and supplying a developing solution to the plate surface of a PS plate, passing it through a development accelerating means, and further passing a squeeze roller, the used developing solution is transferred to the development accelerating means and Compared to the official technology in which the squeezing roller is supplied from a shower nozzle, the effect of preventing dirt on the development accelerator and the squeezing roller and the occurrence of scumming during printing due to this is improved, and cleaning of the shower nozzle, pump, piping, etc. is improved. is no longer necessary, increasing work efficiency.

Further, according to the present invention, compared to the known technique in which the lower rollers of the development accelerator and the squeezing roller are immersed in a developer, the printing plate is improved by transferring stains caused by the drying of the development accelerator to the PS plate. The stain prevention effect is improved.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views showing an example of an automatic developing machine having a processing apparatus according to the present invention, and FIG. 3 is a cross-sectional view showing an automatic developing machine used in a comparative example. 1...Developing section 3...Developer supply member 8...Developer tank lO...Development accelerator 13...Shower nozzle 15aS15b--Squeezing roller P...Transportation path

Claims (2)

[Claims] (1) After a developer is supplied to the surface of the photosensitive lithographic printing plate to be processed and passed through a development accelerator, a pair of upper and lower apertures are immersed in an immersion tank in which the lower aperture roller holds the developer. In a method for processing a photosensitive lithographic printing plate in which a development process is performed by passing the plate through a roller, substantially unused developer is supplied to the development accelerator while processing of the photosensitive lithographic printing plate is interrupted. Characteristic processing method for photosensitive lithographic printing plates. (2) A means for automatically conveying the photosensitive planographic printing plate while supplying a developer onto the plate surface of the photosensitive planographic printing plate, a development accelerator, and a pair of rollers provided below it so as to be in contact with the development accelerator. In addition, in a photosensitive lithographic printing plate processing apparatus having means for passing through a squeezing roller consisting of a pair of upper and lower rollers, the development accelerating means has a substantially unused plate while the processing of the photosensitive lithographic printing plate is interrupted. 1. A processing apparatus for a photosensitive lithographic printing plate, comprising means for supplying a developer, and means for immersing the pair of rollers and the lower squeezing roller of the squeezing roller in the developer.