JPH01263655A - Developing device for printing plate - Google Patents

Abstract

PURPOSE:To uniformize development with a small volume of a fresh developing soln. by boring plural pieces of discharge ports to the end of a supply pipe for feeding the developing soln. and enclosing these parts with flat plate sheets which have the front ends formed to a nozzle shape, and dropping the developing soln. from the nozzle at the time of coating a small volume of the developing soln. on a printing plate such as PS plate which is carried to the developing device. CONSTITUTION:The developing soln. is dropped and coated on the surface of the PS plate 101 at the time when the PS plate 101 pinched by a pair of carrying rollers 2A, 2B passes on a guide roller 2C. A base slit nozzle part is disposed above the roller 2C for the above-mentioned purpose and is constituted in the following manner: The developing soln. fed by a cylindrical pipe 31 is received by the developing soln. supply square pipe 21 provided with plural pieces of the discharge ports on the outside circumference and the discharged developing soln. is blown down in polyethylene terephthalate base materials 28, 29 enclosing the pipe 21 and is dropped through the nozzle 39 at the throttled bottom end onto the PS plate 101.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an improvement in the application section of a printing plate developing device of a small amount developer application type.

[Conventional technology]

The developing device for printing plates using photosensitive materials, especially for the 23rd plate, is the fourth
As shown in the figure, each function is housed in a frame 1, which is installed on the floor via a jack port 13. Then, a printing plate 101 such as the 23rd edition is supplied from the insertion table 102,
The printing plate is conveyed while being held between conveyance rollers 2A and 2B and held by a guide roller 2C, and a developer is sprayed onto the surface of the printing plate by a shower vibrator 3, and further by a brush roller 5, the photosensitive layer on the wet surface is swelled, dissolved, and peeled off easily. This allows the development to progress, and then it is transported to the next washing process.
The printing plate is washed with a stream of water from a shower vibrator, and in the next rinsing section, a rubber-like gum solution or a rinsing liquid is applied to the surface of the printing plate to protect the surface, and the plate is collected after development.

The developer in the developer tank 9 is circulated and temperature-controlled by the pump P through the heat exchanger 9A, and is repeatedly circulated and used while being discharged from the shower vibe 3 by the pump 8A.

Similarly, the water in the washing tank IO and the rinsing liquid in the rinsing tank 11 are pumped to the shower vibe 3 by pumps 8B and 8C, respectively.
It is recycled and used while being discharged from A and 3C.

However, the temperature is not controlled like a developer.

During this time, although not shown in the drawings, new fluid is also periodically replaced with the concave fluid.

[Problem that the invention seeks to solve]

In this type of printing plate development device, the developer tends to become harsh;
Even if the developer is recycled and refilled with new solution, the developer deteriorates significantly and stable development quality cannot be obtained.Furthermore, the apparatus is contaminated by scattering of the developer in the shower bath.

Therefore, the present applicant filed utility model registration application No. 145 in 1988.
No. 756 proposes a means of applying and developing a printed gold by supplying fresh, freshly diluted developer in small quantities. Then, in order to prevent the developer applied onto the printing plate from spreading uniformly and causing uneven development, two flat sheet materials are placed facing each other with the developer discharge tube in between, and a base slit nozzle is installed. has been established.

However, depending on the size and position of the plurality of discharge ports formed in the discharge tube, the uniformity of the developer solution that is flowed onto the printing plate from the joint of the front two flat sheets changes slightly.

SUMMARY OF THE INVENTION In order to solve these drawbacks, it is an object of the present invention to provide a developing device that can uniformly and stably apply a small amount of developer to the surface of a printing plate.

[Means to solve the problem]

This objective is achieved by the following means.

(1) A discharge pipe having a plurality of discharge ports for discharging the necessary developer in small amounts when the printing plate is conveyed to the development area; and 2
A printing plate developing device that supplies and coats the printing plate with a base slit nozzle composed of a flat sheet, comprising:
A printing plate developing device characterized in that the opening diameter of the plurality of discharge ports is small at the entrance of the discharge pipe and gradually increases as it goes to the back side, without at least decreasing the opening diameter, or (2) the printing plate is conveyed to the development area. A printing plate developing device for supplying and applying a necessary developer to the printing plate in small quantities through a base slit nozzle composed of a discharge pipe having a plurality of discharge ports and two flat sheets, wherein the plurality of The printing plate developing device is characterized in that the discharge ports are openings having approximately the same diameter, and the pitch dimension between the discharge ports is gradually reduced from the entrance of the discharge pipe to the back side without increasing at least.

〔Example〕

Examples of the present invention are shown in FIG. 1, FIG. 2 (A), and (B).

This will be explained using (C) and FIGS. 3(A), (B), and (C).

In the drawings, members having the same functions as those of the conventional example are indicated by the same numbers.

Furthermore, the present invention is not limited to this embodiment.

As shown in FIG. 1, the developing device for printing plates, especially for the 23rd printing plate, using the photosensitive material of the present invention has its various functions housed in a frame L, and is ready to use! -13 installed on the floor. Then, horizontal adjustment is performed using the adjustment nut 13A.

Then, the printing plate 101 such as the 23rd plate is supplied from the insertion table 102 via the preheat roller section 130 and is fed to the conveyance roller 2A.
, 2B and is conveyed while being held by guide rollers 2C. Then, at the base slit nozzle section 20, fresh developer is flowed out in small amounts as necessary and uniformly applied onto the photosensitive layer surface of the printing plate supplied onto the guide roller 2C. Next, in the shallow-bottomed dip developing tank section 50, the printing plate being conveyed is guided by rollers 15 and immersed for development, and the brush roller 5 easily swells, dissolves, and peels off the photosensitive layer on the wet surface. The shower vibes 3A and 3C are conveyed to the next washing process while promoting development.
The printing plate is washed with a stream of water and then proceeds to the next gum step or rinse coating step, where the surface is coated with a gum solution or rinse solution to protect the surface of the printing plate from damage such as scratches. Although not shown, the film is collected after the development process is completed through a drying process.

Here, the shallow-bottomed deep developing tank has a large liquid surface area, and since the printing plate 101 guided by the roller 15 is conveyed and stirred in the liquid, it is easy to evaporate. Therefore, a lid 40 is provided as means for preventing evaporation. Incidentally, dip development using a shallow-bottomed dip development tank is provided to eliminate undeveloped portions, called edge effects, on the collecting side of printing plates caused by coating and development. This undeveloped area is undesirable because it causes staining during the printing process. However, the freshness of the developer here is not required so much.

Next, the supply pump 110 for supplying the developer to the mixing section 60 and the base slit nostle section will be explained.

A developing solution stock solution is put into a cartridge tank 61, and the tank is mounted on a movable pedestal 64 that slides along a fixed pedestal 65.
It is placed upside down and connected from the stopper part 62 of the tank to the injection part of the auxiliary tank 68 with a hose. The upper part of the auxiliary tank 68 forms a tapered section 67 and is open to the atmosphere. However, since the contact area with the atmosphere is small, the stock solution is less likely to be oxidized. The lower part of the auxiliary tank 68 forms a wide portion 68A, and is lower than the lowest part of the cartridge tank 61. By making a part of the auxiliary tank 68 transparent, it becomes possible to know the liquid level inside the cartridge tank, and a float switch SWO is provided as a liquid level detector in the auxiliary tank near the bottom of the cartridge tank. If you do this, the developer solution in the cartridge tank will be used until it is empty, and even if the float switch is activated, there will still be developer solution in the auxiliary tank, so you can replace the cartridge tank with a new solution without stopping the entire device operation. can do. Here, the cartridge tank 61 is convenient because it can be used as a commercially available cubic tanker filled with undiluted solution almost as is. A hose is connected from the outlet of the auxiliary tank 68 to the inlet of the pump 69A, and a hose is connected from the outlet of the pump to the mixing tank 81.

On the other hand, the dilution water tank 71 is connected to the inlet of the pump 69B, and the discharge port of the pump is piped to the mixing tank.

Normally, the discharge amount of each pump is adjusted so that the amount of dilution water is 5 parts per 1 part of the undiluted developer solution. However, the degree of dilution is not limited to this, and can be adjusted in various ways.

In this way, both liquids in the mixing tank are sufficiently mixed by the stirrer 82, and both liquids are mixed while being injected until the float switch SWI detects the detection. Then, after stopping and waiting, when the level detection float switch SW3 in the developer storage tank detects that the remaining amount of developer is low, the valve opening/closing solenoid is activated and the valve 83 at the bottom is activated.
is opened and the developer is fed from a portion 87 near the bottom of the storage tank 85.

During this time, feeding of the developer stock solution and water to the mixing tank 81 is stopped. Then, the mixed developer flows into the developer storage tank, and when the SW2 detects the liquid level, the valve opening/closing solenoid is activated to close the valve, and the developer stock solution and water are injected into the mixing tank again. The forward agitator 82 is driven. This is done so that the mixing dilution of the next loft's developer is completed before the previous lot's developer is consumed. Therefore, the supply of developer from the developer storage tank 85 is not interrupted during printing plate development.

The developer in the developer storage tank 85 is connected from the outlet at the bottom of the tank to the inflow side of the supply pump 110 by piping. The pump 110 is a bellows pump 111°112.1
13 are used in three rows, and suction and discharge are repeated with a phase shift of 120° from each other, so that pulsation on the discharge side is eliminated and uniform developer application is performed. The developing solution discharged from the pump 110 is supplied to the temperature controller 1.
By passing through 15, the developer is sent to the pace slit nozzle section 20 at a constant temperature, and the developer is applied to the printing plate.

Now, the water in the washing tank IO and the rinsing liquid in the rinsing tank 11 are pumped to the shower pipe 3A by pumps 8B and 8C, respectively.

It is used in circulation while being discharged from 3C. During this time,
Although not shown in the drawings, the new liquid and the recess are replaced periodically.

By the way, in the developing device of the present invention, a base slit nozzle is provided so that new solution is always supplied in the amount necessary for coating and development without circulating the developing solution, and a very small amount of surplus developer is stored in a separate collection vat. As a general rule, we use a small-volume development system that disposes of liquid as waste.

Therefore, genuine development using a small amount of fresh developer is always carried out efficiently. The present application proposes a means for stabilizing the uniform application of a small amount, and an example thereof will be explained.

That is, in order to uniformly apply the developer to the surface of the photosensitive material of the printing plate, two sheets of polyethylene terephthalate base, which is used as a paste for photographic photosensitive materials, are stacked on top of each other to form the slit nozzle, and the seam at the tip of the base material is used as the material for forming the slit nozzle. A fixed amount was allowed to flow out onto the printing plate.

Therefore, a square pipe 21 with a plurality of discharge ports 22 as shown in the side view of FIG. 2(A) and the front view of FIG. 3(A)
Holding plates 24 and 25 having flat surfaces parallel to the central axis of the pipe are fixedly provided on both sides of the pipe, and auxiliary holding plates 26 having flat surfaces parallel to the central axis are installed on each of the holding plates. Slightly hard buffer plates 24A, 25A, 26A, and 26B made of plastic or the like are fixed inside the plate and the auxiliary holding plate, and the fixed surfaces of the buffer plates are narrow at the bottom and wide at the top.

Then, the holding bar 27 is fitted through the polyethylene terephthalate base material 28.29 and lowered by its own weight, so that the base material 28.29 is reliably sandwiched and fixed with a similar force. The slit formed at the tip of the slit has a -like slit shape without waving. Therefore, if the developer is fed to the square pipe in this state, the required amount of developer will be discharged from the plurality of discharge ports 22 between the polyethylene terephthalate base materials 28 and 29, and from its tip onto the photosensitive layer surface of the printing plate 101. The coating is being applied.

Here, as shown in FIG. 3(A), the diluted developer is supplied to the discharge pipe 21 through pipes 33, 31 and elbow 32, but the discharge pipe 21 is supplied with the diluted developer through pipes 33, 31 and elbow 32. ) and a square pipe as shown in FIG. 3(D) or a normal round pipe (not shown), the explanation of this embodiment will focus on the case of a square pipe.

The discharge pipe 21 is provided with a plurality of discharge ports 22, and as shown in the cross-sectional view of FIG. The liquid is continuously supplied so that about half the volume of the liquid is filled with the liquid. The discharge port 22 is opened at a location lower than the center, and the over 70-degree developer is dropped from the discharge port 22 between the two flat sheets. Further, there is essentially no problem even if the discharge port is opened at a position slightly higher than the center.

However, as shown in FIG. 3(A), when the discharge ports 22 are opened with the same size, the same height, and the same pitch,
The amount of developing solution discharged from the discharge port 22 near the supply port of the pipe 31 is large, and the amount of developer flowing from the tips of the two flat sheets is also large on the side where it joins with the pipe 31, and decreases as it moves away from it. It will not be uniformly coated on the printing plate.

Therefore, in one embodiment of the present invention, as shown in FIG. 3(B), uniform application is achieved by keeping the pitch constant and making the diameter of the discharge port the same or larger as the distance from the joint with the pipe 31 increases. Achieved the purpose.

Incidentally, in this embodiment, the cross-sectional dimension of the discharge pipe 2I is an outer diameter of 14
The inner diameter is 12 mm square, the length is 850+ nm, the diameter is 2φ to 3 mm, the pitch is 80 mm, the printing plate conveyance speed is 990 nm/min, and the discharge amount is 162 cc/min. However, since the pitch or the discharge port diameter can be selected depending on the discharge amount, the present invention is not limited to the data of this embodiment.

In another embodiment of the present invention, as shown in FIG. 3(C), the diameter of the discharge port is kept constant and the pitch dimension of the discharge port is adjusted to
The goal of uniform application was achieved by gradually making the side the same or smaller.

Incidentally, the internal and external dimensions, length dimensions, and discharge amount of the discharge pipe 21 are exactly the same as in the previous embodiment, the diameter of the discharge port 22 is 21, and the pitch is 100 mm from the side where it joins the pipe 31.
It is changed from m* to 401m. However, the present invention is not limited to the specific data employed in this embodiment.

As explained by the above embodiments, the present invention realizes stable small-volume liquid development. The polyethylene terephthalate base material can then be removed by lifting the holding bar 27 upward. This allows the base to be cleaned.

Further, the holding bar 27 may be a round bar as described above, but
The case of a square bar as shown in FIG. 2(B) is also proposed. That is, the plane parallel to the buffer plate 24A or 25A and the buffer material 2
Square bar 27 whose opposing surface is a plane parallel to 6A or 26B
A, the holding effect of the polyethylene terephthalate base material is good as with the round bar, and the base can be attached and detached by shifting the square bar upward. Further, another embodiment of the means for fixing the polyethylene terephthalate base material 28, 29 is shown in FIG. 2(C). A pressing member 35 is provided on the contact surface of the polyethylene terephthalate base material 28, 29 of the holding plate 24, 25 fixed to the square pipe 21, which can be pressed by the suction force of a magnet and can be opened and closed by a hinge 36. A rubber magnet material 35A is fixed to the member 35.

As a result, the polyethylene terephthalate base material 28, 29 can be attached and detached, and when attached, it is evenly pressed and a uniform slit nozzle is formed.

In the above description, the developer supply pipe is a rectangular vibrator, but it is of course possible to use a cylindrical pipe as described above.

〔Effect of the invention〕

According to the present invention, printing plates such as PS plates can be stably developed with a small amount of fresh developer, and high-quality, highly efficient, and low-cost printing plate development can be realized without developer deterioration. It's been a long time.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of the present invention. FIG. 2(A) is a side view of the proposed rectangular base slit nozzle used in accordance with the present invention. FIG. 2(B) is a partially modified view of FIG. 2(A). Like FIG. 2(B), FIG. 2(C) is also a partially modified view of FIG. 2(A). FIG. 3(A) is a front view of the portion shown in FIG. 2(A). FIG. 3(B) is a layout diagram of the discharge ports in the discharge pipe of the first embodiment. FIG. 3(C) is a layout diagram of the discharge ports in the discharge pipe of another embodiment. FIG. 3(D) is a sectional view of the discharge pipe. FIG. 4 is an overall configuration diagram of a conventional developing device. 20--Base slit nozzle portion 21--Developer supply square pipe 22--Developer solution discharge port 24, 25-m-Holding plate 24A, 25A-m-Buffer plate 26---Auxiliary holding plate 26A- m-buffer plate 27---holding bar 27A-m-square rod 28, 2
9--Polyethylene terephthalate base material (flat sheet) 50--Shallow bottom type dip developer tank section 60--Developer mixing section 110--11 Supply pump Fig. 2 CB)

Claims (2)

[Claims] (1) When the printing plate is conveyed to the development area, the necessary developer is supplied and coated onto the printing plate in small quantities through a base slit nozzle consisting of a discharge tube with multiple discharge ports and two flat sheets. 1. A printing plate developing device characterized in that the opening diameters of the plurality of discharge ports are small at the entrance of the discharge pipe, and are gradually increased toward the back of the discharge pipe without at least decreasing the opening diameter. (2) When the printing plate is conveyed to the development area, the necessary developer is supplied and coated onto the printing plate in small quantities through a base slit nozzle consisting of a discharge pipe with multiple discharge ports and two flat sheets. In the printing plate developing device, the plurality of discharge ports are openings having approximately the same diameter, and the pitch dimension between each discharge port is gradually reduced from the entrance of the discharge pipe to the back side without increasing at least. Characteristic printing plate development device.