JP2561334Y2 - Original copy-prevention film for copying machines that supports shading. - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a film master for producing a printed matter for preventing a character from being used illegally by making a character latent image appear when the copy is made. This is a proposal relating to an improvement of a film master suitable for producing a printed matter in which an image is clearly recognized.

[0002]

2. Description of the Related Art When a copy machine is used, a paper is copied by the appearance of a character latent image such as "VOID", "false" or "copy", and it is known that the paper is not a genuine document. Printed matter for copy protection which is made unalterable is known. Also, there are known prints of a shade-compatible type in which a latent image appears in any part of the shade adjustment range other than the ordinary copying machine density (for example, see Japanese Utility Model Publication No. 3-15337 and Japanese Utility Model Publication No. 4-45903). ).

[0003]

The prior art described above employs a method in which a gradation printing layer is overprinted on a latent image printing layer in which the latent image can be visually distinguished from the background, and the latent image printing layer is formed by the gradation printing layer. Is formed stepwise. Therefore, when the latent image printing layer is applied to a copying machine, the gradation printing layer partially suppresses the reflectance, and even when the copy density is adjusted, a latent image appears at any point on the paper.

In this prior art, a gradation original plate is prepared separately from an original plate for forming a latent image printing layer, and gradation printing is performed before and after the latent image printing. However, there is a problem that the printing becomes expensive, and a gradation color tone is remarkably recognized, so that some printed matter is disadvantageous.

The present invention has been made in view of such prior art. The purpose of the present invention is that a latent image appears even when the density of a copying machine is adjusted, and the printing process is performed only once. An object of the present invention is to provide a copy-preventing film master plate which can be obtained at low cost and can produce a well-formed printed matter suitable for a wide range of documents because the gradation color tone is not extreme.

[0006]

In order to achieve the above-mentioned object, the present invention takes the following technical means: a plate base for plate making is provided with 150 lines of 10% to 15% halftone dots. A first latent image portion in which a background and a latent image are provided with 50% line of 10% to 15%, a halftone dot of 150 lines and 30% and a 50% line of 30%
The background and the second latent image portion on which the latent image has been applied are burned in parallel at a slight distance from each other, and 10% to 10% on the facing boundary between the first latent image portion and the second latent image portion. A gradation portion of 30% is burned.

[0007]

The first latent image portion is formed thinner and the second latent image portion is formed darker than the first latent image portion. Thus, a thin latent image printing portion and a slightly darker latent image printing portion coexist naturally on a sheet printed using this original. Then, when the printed matter is copied at a normal density using a copier, a latent image appears in any part of the dark and light printing section, and when the copy density is set lightly, the latent image is erased from the lightly printed portion but it is darkened. The latent image of the printed portion remains. Conversely, when the copy density is increased, it becomes difficult to distinguish the latent image from the background in a darker printed portion, but the latent image in a lighter printed portion appears remarkably.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, a film base plate A for plate making comprises a first latent image portion 1 which is thinner and a second latent image portion 2 which is slightly darker than that.
The gradation portions 3 are burned in parallel in a state where they are slightly apart from each other, and the gradation portion 3 is burned on the boundary between the two.
The first latent image portion 1 forms a background 4 with halftone dots of about 150% to 15% of 150 lines, and forms a latent image 5 indicated as "copy" with 50% of 10% to 15% of lines. The second latent image portion 2 forms a background 6 with halftone dots of 150 lines and 30%, and forms a latent image 7 displayed as "copy" with 50 lines and 30% of lines.

The gradation portion 3 on the boundary between the first latent image portion 1 and the second latent image portion 2 has a density of 10% to 30%, and the 10% light color side is the first latent image portion. Interfering with 1, 30%
The dark side interferes with the second latent image portion 2. Therefore, the first latent image portion 1 and the second latent image portion 2 do not cause an extreme difference in color on the boundary due to the gradation portion 3.

FIG. 2 shows a first latent image film 11, a second latent image film 12, and a gradation film 13 used for producing the original plate of the present invention. The first latent image film 11 and the second latent image film 12 are arranged side by side at a slight distance from each other, and a gradation film 13 is straddled on the boundary between the two films. Although not shown, the first latent image film 11 corresponds to the first latent image portion 1, but the background is indicated by halftone dots of 150 lines 10% to 15%, and "copy" is indicated by 50 lines and 10% lines. Forming a latent image, and the second latent image film 12 has 150 lines 3
"Copy" the background with 0% halftone dots and 50% 30% lines
Is formed, and the gradation film 13 is further provided with a step density of 10 to 30%. By exposing these films, the original plate of the present invention can be obtained.

Thus, the first latent image portion 1, the second latent image portion 2, and the gradation portion 3 are burned in parallel on the film base A as shown in FIG. 3, and these are integrally formed. Therefore, when printing is performed on a sheet using the original plate of the present invention, a printed matter (not shown) having a first latent image portion, a second latent image portion, and a gradation portion similar to the original plate can be obtained in a single step.

FIGS. 4 and 5 show an embodiment in which a printed matter produced by using the original plate of the present invention is copied. FIG. A latent image 27 consisting of a line appears. As the copy density is decreased, the halftone dot background of 150 lines and 10% to 15% and the latent image of 50 lines and 10% to 15% are not reproduced, and the halftone dot background of 150 lines and 30% is not reproduced. 50
Since 30% of the line is reproduced, it is recognized that the sheet is a copy.

When the copy density is set to a high value, the halftone background of 150 lines and 30% and the latent image of 50 lines and 30% are both reproduced on the copy paper 21 at a high density, making it difficult to recognize the existence of the latent image. , 150 lines of 10% to 15% halftone dot background appear light, and 50 lines of 10% to 15% line latent image 25 appears dark. (See FIG. 5).

In the above-described embodiment, the backgrounds 4 and 6 are formed by halftone dots, and the latent images 5.7 and 7 are formed by lines. Conversely, the background is formed by lines and the latent image is formed by dots. The first latent image portion 1 and the second latent image portion 2 may be provided on the base plate 1 at several places, or the area ratio of the first latent image portion and the second latent image portion may be larger or smaller. The difference is included in the free implementation range of the present invention.

[0015]

[Effect of the Invention] The present invention as described above has the following specific effects. (1) If the density of the copying machine is set to be high, the contrast between the background and the latent image in the first latent image portion becomes remarkable, so that it is easily recognized that the paper has been copied. The latent image cannot be erased from the field of view by adjusting the density range of the copying machine, because the background of the second latent image portion and the contrast between the latent image and the latent image indicate that the paper has been copied. Use can be prevented beforehand. (2) Since printing can be performed on paper in a single step, and the printing operation does not require much labor, the product can be provided at a low cost unlike double printing. (3) The gradation portion forms a shape in which the thinner portion of the first latent image portion and the darker portion of the second latent image portion are naturally fused, so that the appearance is good. (4) Since there is no extreme difference in the percentage value between the first latent image portion and the second latent image portion, slight shading appears on the surface of the printed matter, so this is appropriate for most documents.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of an original plate of the present invention.

FIG. 2 is a cross-sectional view of a film for producing the original plate of the present invention.

FIG. 3 is an enlarged sectional view of the original plate of the present invention.

FIG. 4 is a plan view in which a printed matter is copied at a low density.

FIG. 5 is a plan view in which a printed matter is copied at a high density.

[Explanation of symbols]

 A Plate making film base plate 1 First latent image section 2 Second latent image section 3 Gradation section 4.6 Background 5.7 Latent image

Continuation of the front page (56) References JP-A-61-205179 (JP, A) JP-A-61-213190 (JP, A) JP-A-61-10482 (JP, A) JP-A-6-199085 (JP) , A) Fully open 63-47163 (JP, U) Fully open 61-121,868 (JP, U) Fully open, Showa 61-122869 (JP, U) Fully open, Showa 63-21790 (JP, U) 5-31980 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] (1) A film base plate for plate making, 150 lines, 10%
The first latent image portion having a background and a latent image formed by halftone dots of 15% and 50 lines and 10% to 15% of lines, halftone dots of 150 lines and 30%
The background and the second latent image portion on which the latent image is formed are 30 ° parallel lines, and the second latent image portion on which the latent image has been formed is burned in parallel at a slight distance from each other, on the facing boundary between the first latent image portion and the second latent image portion. An original copy protection film for a copying machine in which a gradation portion of 10% to 30% is imprinted on the copying machine.