JP2002179259A - Slip sheet extracting method of printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slip sheet extracting method of a printing plate capable of certainly removing the inserting paper from a printing plate group having loaded printing plates sandwiching the inserting paper. SOLUTION: In the method of separating and removing the slip sheet while conveying the printing plates one by one from a loaded state of the plurality of printing plates cut like sheets while sandwiching the slip sheet, the uppermost printing plate in a loaded state of the printing plates is sucked by a suction conveying means for sucking and conveying them, and a slip sheet sucking means using an electrostatically sucking method is faced to and contacted with the printing plate and/or the slip sheet sucked by the suction conveying means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing a printing plate from which printing plates stacked on each other are taken out one by one to separate and remove the paper.

[0002]

2. Description of the Related Art Conventionally, a photosensitive or heat-sensitive printing plate has been used as a support from the time of manufacture to before use in order to prevent adverse effects on plate making performance such as scratches, dust and foreign matter on the plate surface. Interleaving paper impregnated with or laminated with a synthetic resin is placed on a printing plate for loading and transportation.

When using the printing plates stacked as described above, it is necessary to take out the printing plates one by one and separate and remove the slip sheets. In some cases, a user who uses a large number of sheets may remove the slip sheet in advance, stack the sheet again, and set the sheet in a plate making machine or the like. Thus, a method for efficiently extracting the slip sheet from a group of printing plates stacked in a large amount is required.

However, in most cases, the slip sheet is in close contact with the surface of the printing plate due to pressurization due to burrs at the time of cutting, a large amount of stacked sheets, and static electricity. Since it was thin, it took a great deal of effort to remove it efficiently and without mistakes.

Especially for direct laser exposure, so-called CTP
Printing plate has high sensitivity for high-speed exposure,
The photosensitive material film surface is very delicate. For this reason, in the conventional method of reducing the pressure and adsorbing the interleaf with a small-diameter rubber pad, there is a case where the pressure drop by the adsorbing pad exerts an influence on the photosensitive material film surface of the printing plate even through the interleaf. In this case, the quality of the image on the printing plate is remarkably reduced as a trace of a pad in the plate making, which is a factor of lowering the productivity throughout the printing process.

[0006]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a method for removing a slip sheet from a printing plate group stacked with the slip sheet in between. It is in.

[0007]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have found the following invention.

A first invention relates to a method for separating and removing interleaving paper while transporting the printing plates one by one from a state in which at least a plurality of printing plates cut into sheets are stacked with interleaving paper interposed therebetween. Then, the uppermost printing plate in the loaded state is sucked by the suction conveyance device for suction conveyance of the printing plate, and then the slip sheet suction device using the electrostatic suction method is sucked by the suction conveyance device. It is characterized in that the printing plate and / or the slip sheet are brought into opposing contact.

The second invention is characterized in that electrostatic suction is used as the suction means of the suction conveyance means.

[0010] A third invention is characterized in that the printing plate is a printing plate for direct laser exposure.

In the method of the present invention, since the slip sheet suction means uses electrostatic suction, it can be set to a lower suction force than the suction conveyance means, and only the slip sheet adhered to the printing plate can be sucked and removed. . Further, even when the slip sheet is not in close contact, the suction printing plate can be used without being separated and dropped because the suction plate has a lower suction force than the suction conveyance means. Also,
By using electrostatic suction for the suction conveyance means, even a printing plate having a large size does not have a partial stress like a reduced pressure suction pad, so that it can be used advantageously without occurrence of breakage or dent. Furthermore, even with a printing plate for direct laser exposure with high sensitivity, the slip sheet can be reliably separated and removed without affecting the photosensitive material film surface.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view showing an example of a slip sheet removing apparatus using the slip sheet removing method of the present invention. A printing plate 1 having a photosensitive layer provided on an aluminum support is placed on a pallet 2 with a slip sheet inserted one by one facing down the photosensitive layer and is left standing. In order to remove the interleaving paper from the plate making machine pallet 6 and reload it, the printing plates 1 are lifted one by one from the uppermost sheet by the suction conveyance means 3 having an electrostatic suction mechanism, and are moved laterally by the movement means 4. After the printing plate 1 is once brought into contact with the interleaf removal table 8 on which the interleaf adsorbing means 7 is arranged, the printing plate 1 is arranged on the pallet 6 for a plate making machine by further moving in the lateral direction.

FIG. 2 is a schematic view of the suction conveyance means 3 as viewed from the suction surface side. FIG. 3 is a schematic cross-sectional view thereof. In the electrostatic attraction mechanism 10, comb-shaped opposing electrodes 13 a and 13 b are adhered to the back surface of an attraction surface sheet 14, and an insulating back plate 12 is adhered. Further, wiring from the voltage supply device 20 to the comb-shaped opposing electrodes 13a and 13b is provided.

The suction and conveyance means 3 descends to a position where it contacts the uppermost printing plate 1, and applies a voltage to the comb-shaped opposing electrodes 13a and 13b of the electrostatic suction mechanism 10 to suction one printing plate 1.
Next, the suction conveyance means 3 moves up. At this time, the suction voltage may be increased by increasing the applied voltage.

After the suction conveyance means 3 is completely lifted, it moves laterally,
When the printing plate 1 reaches a fixed position on the slip sheet removing table 8, the printing plate 1 is brought into contact with the slip sheet suction means 7. The slip-sheet adsorbing means 7 is constituted by an electrostatic adsorbing mechanism similar to the adsorbing and conveying means 3.
A voltage lower than the voltage applied to the comb-shaped opposing electrode of the suction conveyance means 3 is applied. This makes the printing plate 1
When the slip sheet 30 is in close contact with the sheet, only the slip sheet 30 is sucked by the slip sheet suction means 7. After a certain period of time, the suction conveyance unit 3 moves up and performs the lateral movement again. Removed slip paper 30
Is collected from the interleaf sheet adsorbing table 8 by the unillustrated collecting means together with the stop of the voltage application to the interleaf sheet adsorbing means 7.

Next, when the suction and conveyance means 3 reaches a predetermined position on the pallet 6 of the plate making machine, it descends, stops the supply of voltage to the electrostatic suction mechanism 10, and allows the printing plate 1 to stand on the pallet 6 of the plate making machine. Then, they are positioned by a positioning means (not shown) and are sequentially loaded.

As the suction means of the suction transfer means 3, a means based on electrostatic suction or a means based on reduced pressure suction using a vacuum pump, a suction pad or the like can be used.

As the suction surface sheet 14 of the electrostatic suction mechanism according to the present invention, those described in JP-A-59-108915, nylon and polyvinyl chloride resin can be effectively used. In addition, the size of the suction surface sheet is only required to cover at least 20% of the area of the printed wiring board to be sucked, and preferably at least 50%.

The voltage supplied to the comb-toothed counter electrode of the electrostatic suction mechanism according to the present invention depends on the suction area to be conveyed, the size and thickness of the electronic material, the number of termination steps, and the weight.
It can be used in the range of 00V to 7KV. If the electronic material to be conveyed is small and light, the applied voltage may be too high, and if the applied voltage is too high, multiple sheets may be adsorbed. It is desirable to determine the optimum applied voltage by conducting a simple experiment on the appropriate voltage in advance. .

In particular, it is desirable to determine a voltage at which only the slip sheet can be reliably sucked by the slip sheet suction means. It is a preferable embodiment that the suction force of the slip sheet suction means is set to be relatively lower than that of the printing plate suction means, because the printing sheet is sucked to the printing plate together with the slip sheet and does not fall off. When the size of the electrostatic attraction mechanism is the same, it is possible to cope with this by lowering the applied voltage or reducing the area where the attraction ability is generated by the electrostatic attraction.

Further, as the voltage supply device, a DC converter capable of boosting a voltage of several V to several KV can be used. It is preferable that the output voltage can be continuously varied. However, in consideration of the cost, a plurality of devices that output a constant voltage may be used and may be switched by the control device.

The printing plate used in the present invention is a so-called P
As long as the interleaf paper is used in the production stage for the S plate or CTP plate, it does not depend on the support of paper, film, metal, any light source (for example, a semiconductor laser or a YAG laser) of the photosensitive material to be used, and the applied wavelength. Can be used. In particular, a printing plate coated with a silver salt emulsion having a relatively light-sensitive material film surface can also be used. When loading, the photosensitive material film surface can be used either upward or downward.

As the interleaving paper used in the present invention, one obtained by laminating or impregnating a synthetic resin on one or both sides with paper as a support, or one comprising a synthetic resin can be used.

[0024]

EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited to the following examples unless departing from the gist of the invention.

EXAMPLE A photosensitive layer was provided by coating a silver salt emulsion on a 0.24 mm thick aluminum base having a hydrophilic surface, and a 398.times.560 mm thick sheet with a single-sided polyethylene-laminated interleaf paper.
And the 500 sheets were stacked on a pallet with the photosensitive layer facing downward.

An interleaf removal device showing an example of the present invention will be described with reference to FIG. The printing plate 1 manufactured as described above has 50
0 sheets and an interleaf sheet 30 are stacked on the pallet 2 in a state inserted between the printing plates. The present apparatus is an apparatus that takes out the printing plates 1 one by one using the suction conveyance means 3, removes the interleaving paper 30, and reloads the pallet 6 for the plate making machine.

The suction transporting means 3 comprises an electrostatic suction mechanism 10, a mechanism for moving up and down (here, an air cylinder is used), and a guide rail 4 having an air drive as a means for moving in the horizontal direction. .

FIG. 3 is a schematic cross-sectional view of the electrostatic attraction mechanism 10.
No. 45, the comb-shaped opposing electrodes 13a and 13b are adhered, and the insulating back plate 12 is adhered. Further, wiring from the voltage supply device 20 to the comb-shaped opposing electrodes 13a and 13b is provided.

The operation of the suction transporting means 3 will be described.
The suction conveyance means 3 descends to a position in contact with the uppermost printing plate 1, and the comb-shaped opposing electrodes 13 a and 13 b of the electrostatic suction mechanism 10.
A voltage (3 KV) is applied to the printing plate 1 to attract one printing plate 1.
After the suction transport mechanism 3 is completely lifted, it moves laterally, and
When it reaches the upper fixed position, it descends and makes the printing plate contact the interleaf paper suction means 7. The slip-sheet adsorbing means 7 is composed of the same electrostatic suction mechanism as the suction-transporting means 3.
Is applied with a voltage of 1 KV.
Thus, when the slip sheet 30 is in close contact with the printed wiring board 1, only the slip sheet 30 is sucked by the slip sheet suction means 7.

Five seconds after the contact, the suction / conveyance means 3 moves up and moves again. The removed interleaf 30 is collected from the interleaf adsorbing table 8 by a not-shown collecting means together with the stop of the voltage application to the interleaf adsorbing means 7.
Subsequently, when the printing plate 1 reaches a predetermined position on the plate making machine pallet 6, it descends, stops the voltage supply to the electrostatic attraction mechanism 10, and places the printing plate 1 on the plate making machine pallet 6 by a positioning means (not shown). It is designed to be positioned.

The voltage supplied to the comb-toothed opposing electrodes 13a and 13b of the electrostatic chuck mechanism 10 of the present invention is set to 500 V, 1 KV, 1.5 KV, by bringing the printing plate 1 into contact with the electrostatic chuck mechanism 10.
Four steps of 2KV were applied and determined.

Using the above-described apparatus, five pallets of printing plates were successively transferred and loaded onto a pallet of a plate making machine while removing slip sheets. However, suction errors including removal of slip sheets and suction of a plurality of sheets were observed. Therefore, there was no problem in the transfer and loading work, and the work could be performed efficiently.

Plate making was performed using the printing plate loaded on the pallet for the plate making machine, and the printing plate was inspected. As a result, no defect which adversely affected the printing quality was found.

[0034]

As described above, according to the method for removing a slip sheet of a printing plate of the present invention, since the slip sheet suction means uses electrostatic suction, it is necessary to set the suction force lower than that of the suction conveyance means. This can be easily performed by changing the voltage, and only the slip sheet that is in close contact with the printing plate can be absorbed and removed. Further, even when the slip sheet is not in close contact with the printing plate, the suction printing plate has a lower suction force than the suction conveyance means, so that the suctioned printing plate can be used without being separated and dropped. In addition, by using electrostatic suction for the suction conveyance means, even a printing plate having a large size does not have a partial stress unlike a reduced pressure suction pad, so that it can be used advantageously without occurrence of breakage or depression. Further, since a fan, a blower, and a pipe are not required as compared with reduced pressure adsorption, a device for adsorption can be downsized. Even for printing plates for laser direct exposure with high sensitivity, the interleaving paper can be separated and removed reliably, and excellent effects such as good plate making and printing can be achieved without affecting the photosensitive material film surface. Have.

[Brief description of the drawings]

FIG. 1 is a schematic view illustrating an example of a slip sheet removing apparatus using a method of slipping a printing plate of the present invention.

FIG. 2 is a schematic plan view illustrating an example of an electrostatic suction mechanism according to the present invention.

FIG. 3 is a schematic side sectional view illustrating an example of an electrostatic attraction mechanism according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printing plate 2 Pallet 3 Electrostatic suction means 4 Moving means 6 Pallet for plate making machine 7 Interleaf paper adsorption means 8 Interleaf paper removal stand 10 Electrostatic adsorption mechanism 12 Back plate 13 Comb-like counter electrode 14 Adsorption surface sheet 20 Voltage supply device 30 slips

Claims (3)

[Claims] 1. A printing plate that has been cut into at least a sheet is stacked on one sheet and then
In the method of separating and removing the interleaf paper while transporting each sheet, the uppermost printing plate in a loaded state is sucked by a suction transport unit for sucking and transporting the printing plate, and then the electrostatic suction method is used. A method for removing a slip for a printing plate, wherein the slip sheet suction means is brought into contact with the printing plate and / or the slip sheet adsorbed by the suction conveyance means. 2. The method according to claim 1, wherein electrostatic suction is used as the suction means of the suction conveyance means. 3. The method according to claim 1, wherein the printing plate is a printing plate for laser direct exposure.