JPS63223647A - Method for recording register mark for multicolors - Google Patents

Abstract

PURPOSE:To establish a simple multicolor printing technique by forming substantially planar register marks together with an original picture within the effective image region of the original picture. CONSTITUTION:The substantially planar register marks 3 consisting of >=2 different hues Y, M, C are previously formed together with the original picture so as to co-exist with the effective image at the cross symmetrical two points on the top and bottom or the right and left within the effective image region 1 in order to obtain said marks as the independent images within the region 1 at the time of exposing the required original picture. The intrinsic functions of color slippage and matching are thereby provided without cutting printing paper afterward.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method for making a photosensitive printing plate, such as a method for making a lithographic printing plate directly from a draft original by multiple exposure using a copying camera. This invention relates to a method for recording register marks, which are essential in a so-called direct plate making method from a multicolor original.

[Prior art and its problems]

Generally, in color printing, overprinting is performed using at least two or more color inks, so color shift does not occur. Alternatively, separate register marks can be provided and the registers and marks provided on these decomposition films can be used.
A method is used to relatively match the image positions on each color printing plate using the marks as a reference.

Such register marks are placed at the top, bottom, left, and right positions of the paper as a mount, which is larger than the effective image area actually printed, i.e. at each corner outside the effective image area and/or at the midpoint thereof. Attached with the original picture. Register marks outside the effective image area (normally) are subjected to exposure plate making together with the original image through a contact screen, and then subjected to development processing to become a printing plate. Therefore, such a printing plate has a register mark outside the effective image area in addition to the effective image area (so-called printed matter as a product), and as a result, when actually printed on a printing machine, the effective image Printed on printing paper larger than the area. On the intermediate printing press, the register mark can be used to confirm the desired movement by checking the color shift during multi-color printing, but once its role is completed, the register mark is printed. The parts are cut and removed. However, for example, in light printing systems (specifically, simple color printed matter such as pants, flyers, etc.), it is impossible to satisfy the original color misalignment and matching functions without post-cutting the printing paper (9 For example, its value is extremely great in terms of work efficiency.According to this, if register marks, also known as registration marks, are provided within the effective image area, there is no need to cut the printing paper, but +, ], Master or :11, etc., have completely lost their commercial value and are not acceptable.

[Purpose of the invention]

The present invention keeps the indispensable register marks for color printing within the effective image area in a state that does not lack practical value, and cuts and removes the register marks outside the effective image area after D printing. The purpose of this invention is to provide a new lightweight color printing method by fundamentally changing the conventional method.

[Means for solving problems]

An object of the present invention is to form a substantially planar register mark on the printing plate surface together with the original image within the effective image area of the original image in a register mark recording method used for multicolor printing plates. This is achieved by For example, color image formation by multiple exposure is performed using a direct plate camera, as disclosed in Japanese Patent Application Laid-open No. 58-189622, as a plate-making process. Directly expose the required original image,
Next, the photosensitive material on the platen is sent to a processing device and undergoes printing plate processing including printing processing and the like.

In the present invention, when exposing this required original image, in advance, along with the original image, a planar register mark consisting of two or more substantially different hues is obtained as an independent image within the effective image area. It suffices to attach it to multiple locations within the image area, and it is very common to attach it to the top, bottom, left, and right cross objects.
It is only necessary to make it coexist with the effective image in some places. Up down left right,
(Items that cannot be prevented from being attached to the four sides of the building and beyond) shall be installed in at least the two locations mentioned above. It is also possible to paste it on the platen in advance.

The surface shape of the register mark of the present invention refers to a shape that can distinguish two or more different hues, such as a cube, a rectangle divided into two or more parts, a circle, a diamond, It may be of various types such as triangular or polygonal, and the desired purpose can be easily achieved by visually recognizing the color shift in the area adjacent to the planar section divided within one shape. As a result, it has the advantage that it can also be used to check the hue of solid printing, and is much more valuable than the conventional linear objects outside the effective image area. The size of the planar register mark of the present invention can be arbitrarily selected from a size that allows visible color shift to a size that does not affect the commercial value of an effective image. The mark is a direct plate-making material (Silver Pan Plate S) using the silver complex diffusion transfer method.
(produced by Mitsubishi Paper Mills A4), electrophotographic printing presses and bresensitized (PS) made of inorganic and/or free photoconductors.
) It can be applied to all types of plates and plate-making methods, such as when creating a background image in a plate.

An embodiment of the present invention will be described below through plate making using 5PPo (manufactured by Mitsubishi Paperback Co., Ltd.), which is a direct color plate making material, but the method of the present invention is not limited thereto.

〔Example〕

Panchromatic rolled lithographic printing plate (SPPo(三i'lJt[tlF'lJ) wo, real 1ii11fl
61-6861, the original combination of pictures and letters is pasted onto the manuscript shelf, and at the same time the second
The planar register mark of the present invention consisting of Y, M, and C shown in the figure was attached within the 1% area of the effective side to be printed.

A gray contact screen was set on the printing plate surface, and three plates of three-color separation were sequentially exposed imagewise (aperture f=16). The contact screen is G made by Dainippon Screen Co., Ltd.
CDN 150. Different screen angles (15° for cyan, 45° for Mazenk, and O0 for yellow) were used in terms of Q/inch. Of the four versions consisting of black plates with only line drawings obtained without using a separate contact screen, the above Y, M,
C.

As a result of color separation of the register marks at the same time as the original image in the 3rd edition, it was possible not only to prevent color deviations during printing on a damaged printing plate, but also to check the ink coverage at the relevant points.

〔Effect of the invention〕

In addition to the original register mark function, the effective image area was completed to the same size as printing, and by eliminating the previous four-sided cutting process outside the effective image area, a simple multicolor printing method was established. I can figure it out.

[Brief explanation of the drawing]

FIG. 1 shows the recording method of the present invention, FIG. 3 shows the conventional recording method, and FIG. 2 shows the register mark of the present invention. Only the register marks in the figure are shown enlarged for better understanding. 1...Right image area 2...Printing version

Claims (1)

[Claims] A register mark recording method used for multicolor printing plates, which is characterized in that a substantially planar register mark is formed on the printing plate surface together with the original image within the effective image area of the original image. register mark recording method.