JPS63173057A - Method for entering process reference line - Google Patents

Abstract

PURPOSE:To quantitatively correct pattern positions on a machine plate corresponding to the expansion of paper and to accurately and easily execute the correction by entering plural auxiliary reference lines with prescribed intervals in parallel with normal reference lines respectively in plural patterns. CONSTITUTION:Normal register marks 33 are entered on the center position in the right-and-left direction of plural pattern positions 32a-32d formed on a machine plate 31 in a plan view showing an entering state executed by an ADM 25 under control based upon a CNT 22. Plural auxiliary register marks 34a-34d or the like are entered with prescribed intervals (d) in parallel with the normal register marks lines in respective patterns 32a-32d. For instance, the normal register mark line 33 is used on the machine plate 31 used for the initial printing, the auxiliary register mark 34a is used for the machine plate 31 to be used in the next printing and the auxiliary register mark 34b is used for the machine plate 31 to be used in the final printing. When the center lines of respective films are made to coincide with these register marks at the time of process, the correction of pattern positions for expansion of paper in the right and left direction can be completed. In case of contracting the paper in the right and left direction, the auxiliary register marks 34c, 34d are succes sively used.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for marking reference lines for plate making on a printing plate using a drawing machine.

[Conventional technology]

On a printing plate, when a film for pattern exposure is placed and exposure is performed for plate making, it is necessary to write reference lines called register marks for the purpose of regulating the position of the film placement. In recent years, automatic drawing using a drawing machine has generally been used to accurately mark registration marks.

However, only one register mark should be entered for each pattern.In the case of multicolor printing, each printing plate for each color is made with the register marks in the same position, and these printing plates are is used for printing each color, so if the printing paper does not expand or contract, each color will be printed on the same part of the paper, but in reality, as the paper passes through the printing unit for each color, However, the paper gradually stretches in the horizontal and vertical directions, and especially when creating multiple patterns on the printing plate, the stretching in the horizontal direction causes the paper to stretch in the horizontal and vertical directions. Inconsistency in the relative relationship between the image pattern and the printed portion of the paper causes defective printing.

That is, as shown in FIG. 4 is a cutaway side view of the main part, and FIG. 5 is an enlarged view of the X-Y cross section of FIG. When transferring the front line, the leading edge of the paper 3 is held between the claw rest 4 of the impression cylinder 1 and the rotary claw 5 for paper capture, and the paper is transferred to the paper transfer cylinder 2 at a fixed horizontal interval from these. The front edge of the paper 3 is also held by the provided claw stand 6 and rotating claw 7, and at this time, since the facing gap between the impression cylinder 1 and the paper feeding cylinder 2 is about 0.3 m,
If the thickness of the paper 3 is less than 0.3 m, the paper 3 is pulled in a wave-like manner as shown in FIG. 5, thereby causing expansion in the left-right direction.

In addition to this, the paper 3 also expands and contracts in various directions due to the printing pressure it receives during printing, the tensile force while being transferred between printing units and between paper feeders and paper ejection devices, and the flapping of the paper 2 itself. This situation changes depending on the fiber direction of the paper 3, the amount of dampening water supplied, the humidity in the air, etc.

Therefore, conventionally, taking the above conditions into consideration, the position of the image is corrected using the registration mark as a reference, depending on the change in the relative relationship between the image and the paper during plate making.

[Problems to be solved by the invention] However, in the past, the pattern position was corrected using a single register mark as a guideline, which required considerable skill and effort. This poses problems such as the printing may be inaccurate and the printing may have to be reprinted.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention is constructed by the following means.

In other words, in a method of drawing reference lines using a drawing machine on a printing plate with multiple patterns, a plurality of auxiliary reference lines are drawn parallel to the regular reference line and spaced apart from each other at a predetermined interval. The information is to be filled out for each of a plurality of images.

[Effect]

Therefore, by selecting the regular and auxiliary reference lines according to the printing position and the expansion and contraction of the paper, and using these to determine the image position, it is possible to adjust the image position corresponding to the expansion and contraction of the paper. Corrections can be made accurately and easily.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to figures showing examples.

FIG. 2 is a block diagram of the entire configuration, and shows a control unit (hereinafter referred to as CNT) 2 connected to a host computer (hereinafter referred to as HCP) 21.
2 is provided, and a buffer memory (hereinafter referred to as B
M) 23 and an operation panel (hereinafter referred to as 0P) 24 are attached, and a processor such as a microprocessor (hereinafter referred to as C) is attached.
PU) and memory etc. CNT22 receives the drawing data from HCP21 in response to the command from 0P24, stores it in 8M23, controls the drawing machine (hereinafter referred to as ADM) 25 according to the contents, and When a pen support mechanism in the form of an XY recorder is driven on the printing plate placed above, registration marks are written on the printing plate.

FIG. 1 is a plan view of the state of writing performed by the ADM 25 under the control of the CNT 22. For each of a plurality of image positions 32a to 32d provided on the surface of the printing plate 31, a regular registration mark 33 at the center in the left and right direction is shown. , and write a plurality of auxiliary registration marks 34a to 34d in parallel with these at a predetermined interval d.
etc. are entered for each pattern position 321L to 32d. For example, on the printing plate 31 used for the foremost printing, the regular registration mark 3
3 is used, the auxiliary register mark 34m is used on the printing plate 31 used for the next printing, and the printing plate 31 used for the last printing is used.
Then, by using the auxiliary register marks 34b and performing plate making while aligning the center lines of each film with these marks, the correction of the image pattern position with respect to the left-right stretching of the paper is completed.

On the other hand, if the paper is to be reduced in the horizontal direction, the auxiliary register marks 34C and 34d may be used in sequence.

Figure 3 is a flowchart of the operating status according to the configuration shown in Figure 2.
When the CPU of the CNT 22 stores this data in the 8M23, the CPU of the CNT 22 stores this data in the 8M23, and then the CNT 22 transfers data to and from the HCP 21 through the ``Separate HCP and CNT'' 103. In order to stop ADM25 and start controlling ADM25,
The DM 25 writes [Regular registration mark drawing J 11L and "auxiliary registration mark drawing" 112 to the pattern position 32& in FIG. 1, for example.
Go to ``All registration marks have been drawn?'' J 113 is NO
During this time, steps 111 and subsequent steps are repeated for the image positions 32b to 32d sequentially. If YES in step 113, the ADM 25 returns the pen to the initial position by "return to origin" 121, and then returns to step 101. Return to

Therefore, as shown in Figure 1, each register mark is 33°30~
34d is filled in, and the correction of the direct delivery position using these can be done quantitatively as described above, and can be done accurately and easily, so that even an inexperienced person can make plates for each color. It can be done quickly.

However, it is preferable to have the auxiliary registration marks 34a to 34d each having a different length so that the ranking of these marks can be easily determined, but it is preferable to add numbers, symbols, etc. Each line may have a broken line shape or a dotted line shape, and the number and interval d of these lines may be determined depending on the number of colors to be printed and the expansion/contraction condition of the paper.

In addition, for paper expansion and contraction in the vertical direction, each direct loading position 32
It is sufficient to write the regular and auxiliary registration marks 33 and 34 in the same way on each side of & ~ 32d. If the paper is only expanding or contracting, write the registration marks 33 and 34 outside of the regular registration marks 33. Various modifications are possible, such as the need to draw the auxiliary register mark 34 only on one side, either toward the front or inward.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, the correction of the direct feeding position of the printing plate due to the expansion and contraction of the paper becomes quantitative, accurate and easy, and a remarkable effect is achieved in the plate making of the printing plate for printing. is obtained.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a plan view showing the registration state of register marks, Fig. 2 is a block diagram of the entire configuration, Fig. 3 is a flowchart of the operating state, and Fig. 4 shows the impression cylinder and paper. FIG. 5 is a cutaway side view of the main part of the transfer drum, and FIG. 5 is an enlarged view of the x-y cross section of FIG. 21...HCP (upper computer), 22...
...CNT (control unit), 25...ADM (
drawing machine), 31...printing plate, 32a to 32d
...Direct delivery position, 33...Regular registration mark (
regular reference line), 341L to 34d... Auxiliary registration mark (auxiliary reference line), d... Interval. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In a method of drawing reference lines using a drawing machine on a printing plate having a plurality of patterns, a plurality of auxiliary reference lines are drawn parallel to the regular reference line and at predetermined intervals. A method for writing reference lines for plate making, which is characterized in that they are written for each image pattern.