JPH0560586B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for replenishing a developer replenisher when developing a photosensitive lithographic printing plate using an automatic developing device.

[Prior art]

Generally, when developing a PS plate using an automatic developing device, the frequency of replacing the developer stored in the developing tank of the automatic developing device should be as low as possible even if a large number of PS plates are developed. For, P.S.
A replenisher is added depending on the amount of plate to be processed and the time required for the process. That is,
As the amount of PS plate processing increases, the effective components of the developer stored in the developer tank are consumed and the developing ability decreases, eventually making it impossible to achieve the desired development. Adding a replenisher containing active ingredients, and furthermore, if the developer is alkaline, it absorbs carbon dioxide from the air over time, which deteriorates the developing ability of the developer, so in order to compensate for this, The above-mentioned replenisher is added, and these are described in British Patent Application No. 2046931A,
It is described in detail in International Patent Application Publication No. WO82/01086, Japanese Patent Application Laid-Open No. 57-5045, etc.

That is, by replenishing the replenisher to compensate for the decrease in developing ability as described above, the developer performance can be properly restored. Also,
The timing for replenishing the replenisher is set at a time when the performance of the developer does not drop significantly so that the developer can develop the PS plate with almost constant performance. Therefore, if the PS plate is transported at a constant speed (that is, processed in a constant processing time), a predetermined finished quality can be obtained.

[Problem that the invention seeks to solve]

At the time of replacing the developing mother liquor, the mother liquor is in a new state and the developing ability has not decreased. Replenishment fluid is being replenished accordingly. In other words, although the developing mother solution in the fresh state can be used for good development for a while without replenishing the replenisher, the replenisher is being wasted because it is replenishing when it is not originally required. There is a problem that there is.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above-mentioned conventional problems, and to provide a method for replenishing developer replenisher that starts replenishment at an appropriate time and eliminates waste of replenisher so that economical development can be performed. It is about providing.

[Means and actions for solving problems]

The above-mentioned object of the present invention is to provide a method for developing a photosensitive lithographic printing plate using an automatic developing device, in which the processing amount of the photosensitive lithographic printing plate can be processed without replenishment by adjusting the amount of developer mother solution charged when replacing the developer. Set and store the non-refill time corresponding to the actual processing area, and each time a photosensitive lithographic printing plate is actually processed, the required refill time corresponding to the processing area is subtracted from the non-refill time, and the remaining non-refill time is calculated. When the time becomes negative (that is, when the non-replenishment time becomes smaller than the required replenishment time), a replenisher containing at least one component of the developer is replenished for an amount corresponding to the negative time, and thereafter the photosensitive This is achieved by a method for replenishing a development replenisher for a photosensitive lithographic printing plate, which is characterized by replenishing the replenisher at a required replenishment time corresponding to the processing area of the lithographic printing plate.

In other words, the processing amount (processing area) of a photosensitive lithographic printing plate that can be developed satisfactorily without replenishment according to the amount of developer mother solution charged at the time of liquid exchange, is converted into the operation time of the replenishment pump corresponding to that processing amount. (No refill time) is set and memorized, and each time a photosensitive lithographic printing plate is actually processed, the required refill amount corresponding to the throughput is converted into the refill pump operation time and the no refill time is calculated. When the non-replenishment time becomes smaller than the replenishment pump operating time, replenishment of the developer replenisher is started. Thereby, while the photosensitive lithographic printing plate can be developed satisfactorily in the fresh liquid state, unnecessary replenishment of the developer replenisher is not performed, and waste of the replenisher can be prevented.

[Embodiment]

Embodiments of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a schematic sectional view of an automatic developing apparatus for carrying out the method of the present invention. In this automatic developing device, a plurality of spray pipes 2 are provided above the conveyance path, and a plurality of spray pipes 2 are installed in the developing tank 4 during the process of conveying the photosensitive planographic printing plate 3 in the direction of arrow A by the conveyance means such as the feed roller 1. The developer 5 contained therein is sprayed from the nozzle of the spray tube 2 onto the surface of the photosensitive layer of the photosensitive lithographic printing plate 3 using the pump 6, and the surface of the photosensitive layer is further rubbed with a brush roller 7, etc., thereby developing. The used developer is collected in a tank 4. Then, the sensing means 8 senses that the photosensitive lithographic printing plate 3 has been inserted into the developing device, and the pump 6 is thereby activated to start supplying the liquid, and the spraying of the developing liquid from the spray tube 2 is started. When the photosensitive planographic printing plate 3 has passed through all the steps of the automatic developing device, the jetting of the developer is stopped.

When the developer 5 in the tank 4 is used repeatedly for development, the developing ability of the developer 5 decreases, so the replenisher 10 in the replenisher tank 9 is replenished as needed with the replenisher pump 11. are doing. The replenishment pump 11 is connected to the sensing means 8 via a control unit 12, and the control unit 12 controls the replenishment start time and replenishment time of the replenisher 10. When replacing the developer,
By pressing a specific key on the keyboard, you can input the mother liquor preparation amount (A), the possible non-replenishment processing area for each mother liquor (B), and the required replenishment amount per 1 ^m2 .
The non-refill time is stored in the memory 16 of the control unit 12 based on (C) and the flow rate per second of the refill pump (D).

Then, when the development process is started, the length of the photosensitive planographic printing plate is calculated based on the signal sensed by the sensing means 8 and the conveyance speed, and the length of the photosensitive planographic printing plate is The throughput (E) is calculated from the average width in the process, and the refill pump operation time is calculated from the refill amount required per 1 m ² and the flow rate of the refill pump, and subtracted from the non-refill time. The controller 12 controls the replenishment pump 11 so that the replenishment pump 11 starts replenishing the replenisher after the non-replenishment time becomes negative by repeating this process.

FIG. 2 shows a control section 12 that controls the replenishment pump 11.
FIG. The control unit 12 includes a keyboard 13 for inputting data, an input/output unit 14 for inputting signals from the keyboard 13 and the sensing means 8, and outputting an operating signal to the replenishment pump 11, and an input/output unit 14 for inputting signals from the keyboard 13 and the sensing means 8. a microcomputer 15 that performs calculations based on the data;
It consists of a memory 16 for storing calculation results by the microcomputer 15, and the contents of the memory 16 are always saved by a battery 17.
The microcomputer 15 counts the signal input time from the sensing means 8 via the input/output unit 14, and calculates the refill time from this count time and data input from the memory 16 at the refill timing, and calculates the non-refill time. is negative, the replenishment pump 11
Outputs an activation signal to. In this way, the control unit 12
The replenishment pump calculates the replenishment time at each replenishment timing and controls the operation of the replenishment pump so that the replenishment liquid is appropriately replenished according to the amount of development processing.

FIG. 3 is a flowchart showing arithmetic processing in the control section 12.

Amount of mother liquor put into the developing tank when installing an automatic developing device A (), area B (m ² ) of photosensitive planographic printing plate that can be processed without replenishment per mother solution, processing per 1 m ² of photosensitive planographic printing plate When the required refill amount C (ml) and the refill pump flow rate D (ml) per second are entered into the microcomputer from the keyboard, these values are backed up by the battery.
Saved in RAM (memory).

If you press a specific key on the keyboard when replacing the fluid,
From these data stored in RAM (memory), the no-replenishment time P (seconds) during which a photosensitive lithographic printing plate can be developed without replenishment is calculated according to the amount of mother liquor prepared, and is backed up by the battery.
Saved in RAM (memory).

At the replenishment timing every 60 seconds after the automatic developing device is powered on, the replenisher is added according to the amount of photosensitive planographic printing plate processed based on the time counted by the sensing means 8 and the data in the memory 16 during that 60 seconds. Calculate the replenishment time Q (seconds). Then compare P and Q, P
If ≧Q, replenishment is not performed and the value of P-Q is newly set to P, and the sensing means 8 returns to counting, and if P<Q, the replenishment pump is operated for Q seconds to perform replenishment. Thereafter, P=0 is set and the replenishment pump is operated periodically for the calculated replenishment time Q (seconds) to replenish the replenisher.

In this way, the developer replenishment and replenisher-free time during which the photosensitive lithographic printing plate can be developed satisfactorily by the mother liquor in the developing tank without replenishing the mother liquor when replacing the mother liquor,
The developer replenisher can be replenished without waste by determining an appropriate replenishment start time based on the required replenishment time depending on the processing amount of the photosensitive planographic printing plate.

FIG. 4 shows the calculation contents of the replenishment time accompanying actual processing.

Mother liquor preparation amount (A) = 20, area that can be processed without replenishment per mother liquor (B) = 2.5 m ² /, required replenishment amount per 1 m ² of photosensitive planographic printing plate (C) = 250 ml/m ² , replenishment pump Non-refilling time P (seconds) when flow rate (D) = 10ml/second
P=ABC/D=20×2.5×250/10=1250 (seconds) This value (P) is saved in memory when a specific key on the keyboard is pressed.

Replenishment calculations are performed every 60 seconds after the liquid is replaced and the automatic imager is turned on, but the sensing time during that time is not constant depending on the timing of insertion of the photosensitive lithographic printing plate, so the required replenishment time is determined at each replenishment calculation timing. Calculate.

In other words, the average processing width of the photosensitive planographic printing plate per day is 1300 mm, and the conveyance speed of the automatic developing device is 1620 mm/day.
Assuming minutes, the replenishment calculation for the first minute (sensing time is 33 seconds) is as follows.

Q=1300×1620/1000000×33/60×250/10≒29(
Seconds) P-Q=1250-29=1221 Next, the replenishment calculation for the second minute (sensing time is 42 seconds) is as shown below.

Q=1300×1620/1000000×42/60×250/10≒37(
Seconds) P-Q=1221-37=1184 From then on, the same calculation is performed every minute, and when P-Q becomes negative, the value of |P-Q| is output as the replenishment pump operating time. Thereafter, the replenishment time Q (seconds) calculated every minute with P=0 is output as the number of seconds of operation of the replenishment pump.

In this embodiment, replenishment of the replenishing fluid is started when the remaining time of the non-replenishing time becomes negative, but replenishment may be started when the remaining time becomes 0. In addition, in this embodiment, the processing area is calculated as the processing amount of the photosensitive planographic printing plate, but if the width dimension of the photosensitive planographic printing plate can be constant, the processing length of the photosensitive planographic printing plate is calculated from the sensing time, It is also possible to calculate the required replenishment time based on this.

Furthermore, the replenisher supplements the performance of the developer that has deteriorated, and may be a solution consisting of the same components as the developer or only a component that has decreased in the developer. There are no restrictions on the type of

〔Effect of the invention〕

According to the present invention, as long as the photosensitive lithographic printing plate can be developed satisfactorily with a fresh developer, the processing amount is automatically increased when the processing amount reaches a set value without replenishing the replenisher. Start replenishing the appropriate replenisher. Therefore, the amount of replenisher can be saved and economical development can be carried out without any adverse effect on the development processing ability of the photosensitive planographic printing plate.

[Brief explanation of the drawing]

Fig. 1 is a schematic sectional view of an automatic developing apparatus for carrying out the method of the present invention, Fig. 2 is a block diagram of the control section, Fig. 3 is a flowchart showing the method of the present invention, and Fig. 4 is a diagram showing the actual processing. This is a timing chart. Codes in the figure: 1...Feed roller, 2...Spray tube, 3...Photosensitive lithographic printing plate, 4...Developer tank, 5...Developer, 6...Pump, 7...Brush roller, 8... ... Sensing means, 9... Replenishment tank,
10...Replenishment fluid, 11...Replenishment pump, 12...
Control unit, 13...keyboard, 14...input/output unit, 15...microcomputer, 16...memory, 17...battery.

Claims (1)

[Claims] 1. In a method of developing photosensitive lithographic printing plates using an automatic developing device, depending on the amount of developer mother solution used when replacing the developer, the non-replenishing time corresponding to the amount of photosensitive lithographic printing plates that can be processed without replenishment is determined. It is set and memorized, and each time a photosensitive lithographic printing plate is actually processed, the required replenishment time corresponding to the processing area is subtracted from the non-replenishment time, and when the remaining non-refill time becomes negative. and at least one of a developer solution.
Photosensitive lithographic printing, characterized in that the replenishing solution containing two components is replenished for an amount corresponding to the negative time, and thereafter the replenishing solution is replenished at a required replenishment time corresponding to the processing area of the photosensitive lithographic printing plate. How to replenish plate developer replenisher.