JPH0252355A - Processing method and device for developing photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To securely develop both surfaces of a photosensitive planographic printing plate with least necessary amt. of a developing soln. by coating a rear surface of the printing plate with the developing soln. and developing an image while holding the developing soln. by driving a belt having a larger size than a lateral side length of the printing plate with a same transporting velocity of that of the printing plate. CONSTITUTION:The photosensitive plate (PS plate) 12 coated with a specified amt. of a developing soln. is inserted into a space between upper and lower endless belts 46. The developing soln. applied on the rear surface of the PS plate 12 is prevented from causing dropping by the gravity by the effect of the endless belts 46. Thus, the applied developing soln. is held on the rear surface of the PS plate 12. Since the endless belts 46 are installed over the whole area along the lateral direction of the PS plate 12, the developing soln. is held in the whole region of the lateral direction of the PS plate 12. The PS plate 12 is carried while holding the developing soln., and the development of the PS plate 12 proceeds during the carrying. Thus, both surfaces of the PS plate 12 are developed securely with least necessary amt. of the developing soln.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a photosensitive lithographic printing plate (hereinafter referred to as P
The present invention relates to a method and apparatus for developing a photosensitive lithographic printing plate (sometimes referred to as S plate).

[Prior Art] A photosensitive lithographic printing plate on which an image has been printed is conveyed to a photosensitive lithographic printing plate developing device and developed.

This development involves the so-called dip method, in which the photosensitive lithographic printing plate is conveyed into a developer tank containing a developer and then immersed in the development process.While the photosensitive lithographic printing plate is conveyed horizontally, the developing Horizontal conveyance spray development method, in which the development process is carried out while spraying, or metering, in which the photosensitive lithographic printing plate is conveyed and the required amount of substantially unused developer is applied to the plate surface for the development process. However, in the case of the above-mentioned dip method, the photosensitive lithographic printing plate is immersed, so a large amount of developer is charged, and as the number of sheets processed increases, the developer deteriorates and new developer must be replenished. Requires a large amount of developer. Furthermore, a developer replenisher replenisher, piping, etc. are required for replenishment, making the apparatus complicated. Furthermore, in order to make the concentration of the developer uniform, the developer must be circulated, which also causes the problem of complicating the apparatus. Furthermore, when replacing the developer with a new developer, there were cases where the developer that was still usable was discarded. For this reason, it has not been possible to use the developing solution efficiently without wasting it.

In the horizontal conveyance spray development method, the developer must be circulated, which similarly complicates the apparatus.

On the other hand, in the case of the metering method, compared to the above-mentioned depth method and horizontal conveyance spray development method, development is always carried out using unused developer, so there is no need for a developer replenisher replenishment device or a complicated circulation device. It has the advantage of being easier.

In this metering method, a method has been proposed in which a developer is applied to the photosensitive planographic printing plate while it is conveyed in the vertical direction.

However, in this case, the applied developer naturally falls downward and stains the photosensitive planographic printing plate located below.
There is a problem of contaminating the inside of the device and its surroundings.

Further, in the case of the above-mentioned vertical conveyance, the direction of the photosensitive planographic printing plate being conveyed along the substantially horizontal direction must be changed to the substantially vertical direction, and a guide, a conveyance roller, etc. are required. For this reason, it has been proposed that the photosensitive lithographic printing plate be conveyed in a substantially horizontal direction and subjected to development processing.

[Problems to be Solved by the Invention] However, when the photosensitive planographic printing plate is conveyed in a substantially horizontal direction and the developer is applied using the metering method,
If the plate on which the image is recorded is on the top side, the developer will be held on the plate without falling downward, but if the plate is on the bottom side, the developer will fall naturally. , it was not possible to develop the lower surface, and it was not possible to reliably develop both the upper and lower surfaces of the photosensitive planographic printing plate.

The present invention takes the above-mentioned drawbacks into consideration, and an object of the present invention is to provide a method and apparatus for developing a photosensitive lithographic printing plate, which can reliably process both the upper and lower surfaces with the minimum amount of developer required.

[Means for Solving the Problems] The present invention provides a photosensitive lithographic printing plate development method and apparatus for developing a photosensitive lithographic printing plate on which an image has been printed, the method and apparatus comprising: After applying a predetermined amount of a substantially unused developer to the plate, the plate is conveyed in a substantially horizontal direction, and a plate is provided on the side of the surface of the photosensitive planographic printing plate coated with the developer and in the width direction of the photosensitive planographic printing plate. The present invention is characterized in that the belt, which is larger than the length of the plate, is driven at substantially the same speed as the conveyance speed of the photosensitive planographic printing plate, while holding and developing the developer applied to the photosensitive planographic printing plate.

[Function] In the present invention having the above configuration, the photosensitive planographic printing plate on which the image has been printed is conveyed in a substantially horizontal direction after a predetermined amount of developer is applied to both the upper and lower surfaces, and The applied developer is held by the large belt, which is conveyed at substantially the same speed as the photosensitive planographic printing plate.

The transport speed is preferably within ±30%, more preferably within ±15%, of the transport speed of the PS plate from the viewpoint of preventing scratches on the PS plate and retaining the developer. Suitable materials for the belt include those with a soft surface such as silicone rubber, ethylene-propylene rubber, rubber such as NBR, felt, and artificial leather so as not to scratch the surface of the photosensitive layer. As a result, the photosensitive planographic printing plate is uniformly developed.

The preferred amount of developer is 5 cc/m' to 300 cc
/ m', more preferably 20 cc/m=20
0 cc/m'. In addition, as for the developer, the viscosity of the developer is 25°C as described in Japanese Patent Application No. 63-1701.
5cps ~ 10000cps, further patent application 1986-30
50 dyne/at 25°C as described in No. 7056.
It is preferable to use a developer having a size of less than cm. The predetermined amount of the developer can be applied by various methods such as spraying, wire bar roller gravure roller, curtain coater, and application by dropping from a nozzle that moves from side to side.

As described above, in the present invention, it is possible to reliably develop both the upper and lower surfaces by applying the minimum amount of developer to the photosensitive planographic printing plate.

[Embodiment] FIG. 1 shows an embodiment of a photosensitive lithographic printing plate processor 10 to which the present invention is applied.

The photosensitive planographic printing plate processor 10 includes a developing section 14 for developing the photosensitive planographic printing plate 12 on which images have been printed on both upper and lower surfaces by a printing device (not shown), and a 23rd plate 12 after development.
and a desensitization treatment section 18 for applying a desensitization treatment liquid to the 23rd plate 12. These developing section 14, water washing section 16, and desensitizing section 18 are provided in this order, and the PS plate with images printed on both the upper and lower surfaces is conveyed substantially horizontally and processed.

As shown in FIG. 1, a pair of conveying rollers 20 are arranged on the side where the 23rd plate 12 is inserted into the developing section 14. As shown in FIG. A 23rd printing plate 12 with images printed on both its upper and lower surfaces by a printing device (not shown) is inserted between the pair of transport rollers 20.

The developing section 14 is equipped with a drain liquid collection tank 22 . This drain liquid recovery tank 22 is open at the top and has a substantially inverted mountain shape with the bottom center portion protruding downward. The developer used for development is discharged from the bottom of the drain liquid recovery tank 22.

A developer applying roller pair 26 is arranged above the developer measuring tank 24 . Further, a pair of conveying rollers 28 is arranged above the developing section 14 and on the downstream side of the pair of developer application rollers 26 . The pair of developer application rollers 26 and the pair of transport rollers 28 are rotatably supported by a pair of side plates (not shown), and are rotated by the driving force of a driving means (not shown) transmitted thereto. 23 plate 1 sent out from conveyor roller pair 20
2 is conveyed along a substantially horizontal direction above the drain liquid collection tank 22 by a pair of developer application rollers 26 and a pair of conveyance rollers 28, and sent to the washing section 16.

The developer application roller pair 26 is composed of an upper developer application roller 26A located above the transport path of the 23rd plate 12, and a lower developer application roller 26B located below the transport path of the 23rd plate 12. .

A developer reservoir roller 30 is arranged above the upper developer application roller 26A. This developer reservoir roller 30
A spray pipe 32 is arranged between the upper transport roller 26A and the upper transport roller 26A. The spray pipe 32 has a plurality of discharge ports opening in the axial direction toward the contact portion between the developer reservoir roller 30 and the application roller. One end of the spray pipe 32 communicates with a conduit 34 that communicates with the bottom of the developer tank 13 . A developer supply pump 3 is located in the middle of the pipe line 34.
6 is arranged, and when the developer supply pump 36 operates, the developer in the developer tank 13 is supplied to the spray pipe 3.
2. The supplied developer is discharged from a plurality of discharge ports, guided by the developer reservoir roller 30, and supplied to the outer periphery of the upper developer application roller 26A. One end of a pipe line 35 communicating with the developer tank 13 is open in the developer measuring tank 24, and a developer supply pump 37 is installed in the middle of the pipe line 35.

As a result, the developer in the developer tank 13 is transferred to the developer measuring tank 2.
4. Also, developer measuring tank 2
A pipe line 38 communicating with the bottom of the developer tank 4 has one end open to the developer tank 13, and a valve 39 is installed in the middle of the pipe line 38. This allows excess developer in the developer measuring tank 24 to be collected into the developer tank 13. Approximately half of the outer circumference of the lower developer application roller 26B is
It is immersed in a developer contained in a developer measuring tank 24 . Thereby, the developer in the developer measuring tank 24 is brought out by the rotation of the lower developer applying roller 26B.

A developer holding device 40 is arranged below the conveyance path on the downstream side of the developer application roller pair 26 in the conveyance direction of the PS plate 12 .

As shown in FIG. 1, the developer holding device 40 is connected to the PS plate 1.
They are arranged above and below the conveyance path No. 2. As shown in FIG.
Rollers 42, 44 are arranged along the conveyance direction of 2. These rollers 42 and 44 are pivotally supported by a pair of side plates (not shown), and are rotated by the driving force of the driving means being transmitted thereto.

A wide endless belt 46, which is larger than the width of the PS plate 12, is wound between the rollers 42 and 44.

This endless belt 46 is conveyed by rotation of rollers 42,44.

A roller 48.50 having a smaller diameter than the roller 42.44 is arranged between the rollers 42.44. These rollers 4
8.50 is in contact with the PS plate 12 of the endless belt 46, and supports the endless belt 46 so that it does not slacken.

The developer holding device 43 placed above the transport path of the PS plate 12 has the same structure as the developer holding device 40 placed below, but rollers 48 and 50 are placed between the rollers 42 and 44. do not have. This is because the developer applied to the upper surface of the PS plate 12 is adhered to the PS plate 12, but the developer applied to the lower surface falls downward, so it is held by the endless belt 46. For this reason, the intermediate portion of the endless belt 46 needs to be flat, so the developer holding device 40 disposed below is provided with rollers 48 and 50. or,
The developer holding device 43 can be removed if necessary.

A spray pipe 52 for discharging a cleaning liquid is disposed between the developer holding device 40 and the pair of transport rollers 26 . This spray pipe 52 is communicated with a wash water tank 56 through a conduit 54. A wash water supply pump 58 is disposed in the middle of the pipe line 54, and when this pump operates, wash water is supplied to the spray pipe 52.

The spray pipe 52 has a plurality of discharge ports formed along the axial direction, and opens toward between the upper and lower endless belts 460.

The cleaning spray can be activated after the apparatus is stopped or, if necessary, after the conveyance of 28 plates is completed.

A developer is stored in the developer tank 13 , and a pipe line 34 is connected to the bottom of the tank 13 , and a pump 36 sends the developer to the developer measuring tank 24 . The developer tank 13 can be equipped with a temperature regulator or a stirrer if necessary.

When the developer in the developer tank 13 further decreases, the developer is supplied to the developer tank 13 by a developer supply device (not shown).

Further, one end of a pipe line 64 is connected to the bottom of the drain liquid recovery tank 22 . A valve 66 is disposed in the middle of this conduit 64. By opening this valve 66, the drain liquid collection tank 2
The used developer in 2 is discharged to a drain tank 45.

The washing section 16 is equipped with a washing tank 76, and the washing tank 76 has the same shape as the waste liquid collection tank 22.
Molded smaller. Above this washing tank 76, there are two pairs of conveying rollers 68 along the conveying path of the PS plate 12.
70 are arranged in order. These conveyor roller pairs 68
The pair of transport rollers 70 are pivotally supported by a pair of side plates (not shown), and are rotationally driven by the driving force of a driving means (not shown). With this drive, PS version 12
is conveyed in a substantially horizontal direction.

Spray pipes 72, 74 are arranged between the transport roller pair 68 and the transport roller pair 70.

The spray pipe 72 is disposed above the conveying path of the PI3 8 plate 12 by the pair of conveying rollers 68, and the spray pipe 74 is disposed below the conveying path of the 28 plate 12 by the pair of conveying rollers 70. These soufflé pipes 72
, the spray pipe 74 is provided with a plurality of discharge ports along the axial direction, and the spray pipe 72 is provided with a plurality of discharge ports along the axial direction.
8, the spray pipe 74 opens toward the conveying roller pair 70.

One end of the spray pipe 72 and the spray pipe 74 communicates with a conduit 78 that communicates with the bottom of the washing tank 76 .

A flush water supply pump 80 is disposed in the middle of this pipe line 78, and by the operation of this flush water supply pump 80,
Rinsing water 82 stored at the bottom of the washing tank 76 is supplied to the spray pipe 74 and the spray pipe 74.

Further, one end of a pipe line 84 is connected to the bottom of the washing tank 76 . A valve 86 is disposed in the middle of this conduit 84, and when the valve 86 is opened, the washing water 82 in the washing tank 76 is discharged. Furthermore, conduit 8
5 is arranged so that water is replenished and overflow liquid is discharged to a drain tank 45 as necessary.

The desensitization treatment section 18 is equipped with a desensitization treatment tank 88 . A desensitizing solution is stored at the bottom of the desensitizing tank 88 .

Two pairs of conveyance rollers 90 and 92 are arranged above the desensitization treatment tank 88 along the conveyance direction of the 28 plate 12. The pair of conveyance rollers 90 and the pair of conveyance rollers 92 are pivotally supported by a pair of side plates (not shown), and are rotated by the driving force of a driving means (not shown).

The 28 plate 12 sent out from the pair of conveying rollers 70 is inserted into the pair of conveying rollers 90, and is conveyed substantially horizontally by the pair of conveying rollers 92.

Spray pipes 94 and 96 are arranged between the pair of transport rollers 90 and the pair of transport rollers 92. The spray pipe 94 is connected to a pair of conveyor rollers 90 and the 28 plates 12
The spray pipe 94 is arranged above the conveyance path of the 28 plate 12 by a pair of conveyance rollers 92 .

1, the spray pipe 94 has a plurality of discharge ports formed along the axial direction, the spray pipe 94 faces the pair of transport rollers 90, and the spray pipe 94 faces the pair of transport rollers 92. It is opened towards.

The spray pipe 94 has one end communicating with a conduit 98 that communicates with the bottom of the desensitization treatment tank 88 . A supply pump 100 is disposed in the middle of this pipe line 98, and the operation of this supply pump 100 supplies the desensitization treatment liquid in the desensitization treatment tank 88 to the spray pipe 94 and the spray pipe 94. It has become.

Further, one end of a conduit 104 is connected to the bottom of the desensitization treatment tank 88 . A valve 10 is located in the middle of this conduit 104.
6 is arranged, and by opening this valve 106, the desensitizing treatment liquid 102 in the desensitizing treatment tank 88 is discharged. Further, a conduit 105 is arranged so that desensitizing liquid is replenished as necessary and overflow liquid is discharged into a drainage tank 45.

Next, the operation of this embodiment will be explained.

The 28 plate 12, on which images have been printed on both upper and lower surfaces by a printing device (not shown), is inserted into a pair of transport rollers 20, and then inserted between a pair of developer application rollers 26. The 28 plate 12 inserted between the pair of developer application rollers 26 is conveyed substantially horizontally to between the pair of conveyance rollers 28 .

The 28 plate 12 passing between the developer measuring tank 24 is applied to both upper and lower surfaces by the upper developer application roller 26A1 and the lower developer application roller 26.
A predetermined amount of developer is applied by B. The amount of this developer is set to the minimum required for developing 28 plates 12.

The 28 plate 12 having a predetermined amount of developer applied to both upper and lower surfaces by a pair of developer application rollers 26 is transported with the developer on the upper and lower surfaces held by a developer holding device 40 .

The 28 plate 12 coated with the developer is placed on the upper and lower endless belts 46.
inserted between. With this endless belt 46, 28 editions 1
The developer applied to the lower surface side of 2 is prevented from falling naturally, and the applied developer is retained. Also endless belt 4
6 are provided over the entire width direction of the PS plate 12, so that the developer can be held over the entire width direction of the PS plate.

Furthermore, the PS plate 12 is conveyed while retaining the developer, and during this conveyance, the development of the PS plate 12 progresses and is subjected to development processing.

As a result, both sides of the PS plate 12 can be reliably developed using the minimum necessary amount of developer.

PS plate 1 with developer applied to both top and bottom surfaces and developed
2 is sent to the washing section 16 by a pair of conveying rollers 28. The PS plate 12 sent out from the transport roller pair 28 is inserted between the transport roller pair 68. The PS plate 12 inserted into the transport roller pair 68 is transported in a substantially horizontal direction and inserted between the transport roller pair 70. During this transportation, PS version 12
Washing water is applied to both upper and lower surfaces by the spray pipe 72 and the spray pipe 74 and is washed with water. After being washed with water, the PS plate 12 is inserted between a pair of conveyance rollers 90 and sent out between a pair of conveyance rollers 92, and is sent to a desensitization processing section 1.
8 in a substantially horizontal direction. During this conveyance, a desensitizing treatment liquid is applied by the spray pipes 94 and 96. The PS plate 12 coated with the desensitizing treatment liquid is sent out of the photosensitive planographic printing plate processor 10 by a pair of transport rollers 92 and is transported to a drying device (not shown).

After the conveyance of the PS plate 12 is completed, the developer adhering to the belt 46 is washed away by the washing water supplied to the spray pipe 52.

When printing was performed using the printing plates treated as described above, good printed matter similar to the conventional one was obtained in both cases.

[Effects of the Invention] As explained above, the present invention provides a photosensitive planographic printing plate development processing method and apparatus for developing a photosensitive planographic printing plate on which an image has been printed, which comprises: After applying a predetermined amount of a substantially unused developer to the lower surface, the plate is conveyed in a substantially horizontal direction, and is provided on the side of the developer-applied surface of the photosensitive planographic printing plate in the width direction of the photosensitive planographic printing plate. The invention is characterized in that a belt larger than the length of the plate is driven at substantially the same speed as the conveyance speed of the photosensitive planographic printing plate, while holding and developing the developer applied to the photosensitive planographic printing plate. Therefore, an excellent effect can be obtained in that both sides of the photosensitive planographic printing plate can be reliably developed with the minimum necessary amount of developer.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of a photosensitive lithographic printing plate processing machine to which the present invention is applied, and FIG. 2 is a perspective view showing a developer holding device. DESCRIPTION OF SYMBOLS 10... Photosensitive lithographic printing plate processor 12... PS plate, 14... Developing section, 24... Developer measuring tank, 26... Conveyance roller pair, 32... Spray pipe, 40 .43...Developer holding device.

Claims (4)

[Claims] (1) A photosensitive lithographic printing plate development method and apparatus for developing a photosensitive lithographic printing plate on which an image has been printed, wherein a substantially unused developer is applied to at least the lower surface of the photosensitive lithographic printing plate. After applying a predetermined amount, the photosensitive planographic printing plate is conveyed in a substantially horizontal direction, and a belt, which is provided on the side of the photosensitive planographic printing plate on which the developer is applied, and is larger than the length in the width direction of the photosensitive planographic printing plate, is transferred to the photosensitive planographic printing plate. 1. A method for developing a photosensitive lithographic printing plate, characterized in that the development process is carried out by holding a developer applied to the photosensitive lithographic printing plate while driving the plate at substantially the same speed as the conveyance speed of the photosensitive lithographic printing plate. (2) A photosensitive lithographic printing plate development processing apparatus for developing a photosensitive lithographic printing plate on which an image has been printed, comprising a conveying means for horizontally conveying the photosensitive lithographic printing plate, and the photosensitive lithographic printing plate. a coating means for applying a predetermined amount of a substantially unused developer to at least the lower surface of the plate; and a coating means provided on the side of the surface of the photosensitive planographic printing plate coated with the developer and extending in the width direction of the photosensitive planographic printing plate. and a belt larger than the length of the plate, and the belt is driven at substantially the same speed as the conveyance speed of the photosensitive lithographic printing plate while retaining and developing the developer applied to the photosensitive lithographic printing plate. A photosensitive lithographic printing plate development processing apparatus characterized by: (3) The method for developing a photosensitive lithographic printing plate according to claim (1), characterized in that a predetermined amount of a substantially unused developer is applied to both upper and lower surfaces of the photosensitive lithographic printing plate. Printing plate development processing method. (4) The photosensitive lithographic printing plate development apparatus according to claim (2), further comprising a coating means for applying a predetermined amount of substantially unused developer to both upper and lower surfaces of the photosensitive lithographic printing plate. Photosensitive lithographic printing plate development processing equipment.