JPH0520536Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a film positive original plate used for producing printed matter that can be immediately recognized as not genuine when copied.

[Prior Art] In order to prevent forgery caused by copying, a latent image consisting of lines or halftone dots and a background consisting of halftone dots or lines are applied to the surface of the paper so that they cannot be seen with the naked eye. Printed matter is known in which the latent image is visually recognized as distinct from the background, making it known that it is a copy (for example, JP-A-60-79991 and JP-A-60-119560
(see publication).

The former technique involves preparing an original plate for the latent image and background on one side, and an original plate for a pattern such as a floral pattern on the other. After printing the latent image and background, the pattern is overlaid with light-colored ink that cannot be reproduced by copying. It takes the means of printing. According to this technology, the latent image on printed matter can be hidden by the pattern and can also have a decorative effect, and when it is applied to a copying machine, the light-colored pattern is blown away, making it possible to distinguish the latent image from the background and make it visible. It is.

In addition, the latter technology incorporates a camouflage pattern into the original plate for the latent image and background, and the latent image on the surface of the printed matter and the background are formed with minute divided patterns by the camouflage pattern, making the latent image invisible to the naked eye. The image was made so that it could not be identified.

[Problem that the invention aims to solve] The former technique, which uses two original plates, requires two printing processes to produce printed matter, which is laborious and expensive, and has disadvantages that are not appropriate for documents that do not use patterns. be.

In addition, although the latter technique is one-time printing, the latent image and background are separated by a camouflage pattern, resulting in an unnatural appearance on the surface of the printed matter, and even after copying, the latent image and background are separated by a camouflage pattern. There was a problem in that the naked eye was dazzled by the interference and the latent image could not be seen clearly.

[Means for Solving the Problems] The present invention takes the following technical means to solve the problems of the prior art described above. A latent image consisting of a background consisting of lines and halftone dots, or a background consisting of halftone dots and lines is imprinted on the photosensitive film, and together with the background and the latent image, an interval wider than the lines is printed. This is a printing film positive original plate that has a line pattern printed in the direction that intersects the horizontal lines.

[Function] If the background printed on the photosensitive film of the base plate is lined lines, the latent image will be composed of halftone dots, and if the background is halftone dots, the latent image will be composed of lines. On the printed paper, a background with different component shapes and a latent image are applied, and at the same time, the line pattern burned into the original plate is also printed on the entire surface of the paper. When this printed matter is run as a manuscript in a copying machine, the background or latent image made up of lines is reproduced, but the latent image or background made up of halftone dots is not, resulting in a difference in shading between the two. The line pattern is reproduced in the same way as the line pattern, but since the spacing is wider than the line pattern, this does not become an obstacle, and the background and line pattern can be clearly recognized.

[Example] A film base plate 1 for plate making has a photoresist film 2 coated on its surface, and is first exposed to 65 lines and 10% horizontal lines by first exposure from a light source (not shown). A background 3 consisting of is printed. and by the second exposure
A latent image 4 labeled "copy" consisting of 175 lines and 10% halftone dots is printed into the white area of the background 3, and a vertical line pattern intersecting with the parallel lines of the background 3 is created by the third exposure. 5 is burned in, and thus the background 3, latent image 4, and line pattern 5 are all formed on the same plane as shown in the first figure.

If the spacing between the lines of line pattern 5 is extremely narrow, the latent image will be difficult to see when copying the printed matter, and if it is too wide, the camouflage effect before copying will be lost, so the spacing between the lines should be about twice the line spacing. It is preferable that there be. In other words, as shown in the second diagram, the original plate has a one-plate configuration in which a background 3, a latent image 4, and a line pattern 5 are provided on the base plate 1. When one-color printing is performed on paper using this original plate, it will appear on the paper. Similar to the original plate, a background consisting of parallel lines, a latent image consisting of halftone dots, and a line pattern are applied at the same time. Originally, the lines and halftone dots have minute shapes, so the latent images are not so clearly visible, but if you observe them carefully, you can see them. Therefore, if a line pattern is applied, the lines and halftone dots will interfere, dazzling the naked eye, and as a result, the latent image will not be discernible at all. When the printed matter formed in this way is run on a copying machine, the lines are reproduced, so the background 3' appears in dark color on the copy paper 1', whereas the halftone dots are not reproduced, so a latent image 4 appears. ' becomes a white background, and the latent image 4' becomes clear due to the contrast between the two. At this time, the line pattern 5' is also reproduced, but the line spacing is wider than the parallel lines and the copying effect of the parallel lines and halftone dots is not affected in the slightest, so the latent image 4' is fully visible (the third (see figure).

In the above-mentioned embodiment, the background 3 is made up of lines and the latent image 4 is made up of halftone dots, but the background 3 may be made up of halftone dots and the latent image 4 is made up of lines. The latent image 4 may be provided at a plurality of locations on the base plate 1.

[Effect of the idea] The present invention has the following unique effects.

(1) The line pattern is arranged in a manner that intersects the lines that make up the background or latent image, so it has the effect of distracting the lines from the naked eye, and the line pattern also interferes with the halftone dots, making it difficult to decipher the latent image on printed matter. The surface of the printed matter is observed to be uniform and flat due to the line pattern, giving it a good appearance.

(2) Unlike conventional camouflage patterns, the line pattern does not divide the latent image into random shapes, and has appropriate line spacing, so it does not affect the copying effect of lines and halftone dots. When a printed matter is copied, the latent image is clearly visible.

(3) The line pattern imparts a beautiful decorative effect to the printed matter by adopting a shape suitable for the purpose of the printed matter, such as wavy or straight lines.

(4) Since the entire plate is printed in one color, unlike the overprinting method, the printing process only needs to be done once, which is efficient and allows printed matter to be provided at low cost, as well as eliminating the need for partial concealment with floral patterns, etc. Can be used for a wide range of documents.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing an example of the original version of the present proposal;
The figure is a plan view of the original version, and FIG. 3 is a plan view of a printed matter made from the original version. 1...Base plate, 2...Photosensitive film, 3...Background, 4...
...Latent image, 5...Line pattern.

Claims (1)

[Scope of utility model registration request] A latent image consisting of a background consisting of parallel lines and halftone dots, or a latent image consisting of a background consisting of halftone dots and parallel lines, is printed onto the photoresist film coated on the surface of the film base plate for plate making, and the background and A film positive original plate for printing on which a latent image and a pattern of lines that are spaced wider than the lines and intersect with the lines are imprinted.