JP2000168224A - Security having minute letters - Google Patents

Abstract

PROBLEM TO BE SOLVED: To utilize effectively the presence or absence of cell shapes characteristic of gravure printing for the purpose of preventing forgery, by printing minute letters of a specified letter height or below on a relatively small printing region by the gravure printing. SOLUTION: A color containing minute letters of a letter height 380 μm is color-separated into cyan, magenta and yellow by a scanner. Image data of each of these colors are read by an electronic engraving machine and engraved thereby on a gravure cylinder. A gravure plate face of each of these colors is printed on a sheet T by a gravure printing machine and a stamp K with 50 faces is thereby made on the sheet. In a pattern of one face K' thereof two peaks Y are printed with magenta, a rate amount letter R with cyan and background wave lines X with yellow. The wave lines X are constituted of minute letters disposed in the shape of waves and the letters can be made out. Moreover the letters themselves are constituted of relatively large engraved cells peculiar to gravure printing which are different from small halftone dots according to offset printing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed matter of securities having minute characters.

[0002]

2. Description of the Related Art At present, as one of measures for preventing color copying of securities, there is a forgery prevention technique using minute characters. According to this method of determining the authenticity of minute characters, minute characters can be read on a printed matter, but when copied, the minute characters are not accurately reproduced and cannot be read, so that differentiation is achieved. Conventionally, printing methods for obtaining minute characters have been printed by offset printing or intaglio printing. First, in offset printing, when printing is performed in the size of ordinary halftone dots, there is a drawback that the print density does not increase, characters are difficult to read, and printing durability is poor. Therefore, the method used for Tokyo Metropolitan Expressway multi-pass tickets and passports is that when the film is output in the plate making process, it is created as a line drawing instead of a halftone dot, and this film is used as a PS.
It is printed on the plate, developed and printed. For this reason, the obtained minute characters are not printed in a halftone dot configuration, and a solid, easily readable print reproduction with a clear character outline is obtained.

[0003] In addition, minute characters formed by intaglio printing have the advantage that minute characters having a small character height can be clearly reproduced as compared with offset printing, and income stamps and the like are printed. However, there are few examples of commercialization using only intaglio printing, and in many cases, offset printing, gravure printing, and intaglio printing are combined. Even on income stamps, intaglio printing including minute characters is printed after offset printing such as copy-forgery-inhibited patterns. For this reason, two printing methods are required, so that the product cost increases and a lot of manufacturing time is required.

On the other hand, with the rapid development of color copiers, various special functions have been added to color copiers.
It is more sophisticated. For this reason, at present, the character height is 50
Even a minute character having a size of about 0 μm is reproduced as a readable copy as a character, though not strictly equivalent, when copied by a color copier. For this reason, the character height of 400 μm,
Offset printing and intaglio printing that can print the following minute characters are advantageous as countermeasures against forgery. However, in offset printing and intaglio printing, the outline of minute characters is printed clearly, so when attempting to forge, it is easy to accurately trace the outline of the character. There was a drawback that it was easy to be done.

On the other hand, gravure printing is widely used for artistic prints such as photographs and paintings, but is not used for printing minute characters. One of the methods for producing a printing plate surface for gravure printing is a mechanical engraving method using an electronic engraving machine. Although this electronic engraving machine is commercially available from various companies, Heidelberg Prepress Helio-Kl
When an ischograph K201 type electronic engraving machine is used, it has been difficult to provide a printed matter that can read minute characters having a character height of 400 μm or less. The original purpose of this electronic engraving machine is to print printed materials using a screen ruling of about 250 lines / inch, such as advertisements and packages, and not to print precise designs. For this reason, in the case of printing a small character with a high forgery prevention effect with a character height of 400 μm or less on the printed matter, it is necessary to perform gravure printing once, and then perform another printing with an offset printing machine or an intaglio printing machine, which is also There are disadvantages that the product cost is high and a lot of manufacturing time is required.

As described above, in the gravure printing method, fine characters are not printed, and they are mainly used for artistic purposes. For example, when minute characters having a character height of 400 μm or less are produced using the above-mentioned electronic engraving machine of Heidelberg Prepress Co., an image obtained by color-separating minute characters N serving as an original with an electronic plate-making device at an image resolution of 400 lines / inch. The data is converted into chromacom format image data so that the data can be recognized by the electronic engraving machine. The maximum resolution of the chromacom format image data is about 200 lines / inch, and the chromacom format image data of the pixels P having the density information as shown in FIG. 1A is obtained. And engraving on the cylinder, it is engraved as an engraving cell S in FIG. 1 (b). Therefore, when gravure printing is performed using this cylinder, a minute character N as shown in FIG.
Cannot be read, and printing of minute characters having a character height of 400 μm or less was not suitable.

[0007]

Therefore, the present inventors have paid attention to overcoming the above-mentioned problems of the conventional method and effectively utilizing the presence or absence of a cell shape which is a feature of gravure printing as forgery prevention.
The present invention provides securities having small characters with a character height of 400 μm or less, which are legible by gravure printing, and uses the cell shape as a forgery prevention means.

[0008]

Means for Solving the Problems A printed matter of securities, characterized in that gravure printing is performed on a relatively small print area, and minute characters having a character height of approximately 400 μm or less are printed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) A color original including minute characters with a character height of 380 μm is color-separated into cyan, magenta and yellow by an electronic plate making machine (scanner), and image data of each color is electronically engraved. Read it on a machine and engrave it on a gravure cylinder. The gravure printing plate of each color was printed and perforated with a gravure printing machine, and a 50 sheet-like stamp K was formed on a sheet of paper T as shown in FIG. FIG. 2 (b) is an enlarged view of one side K 'of the stamp K, in which a perforated perforation Z is provided around the design, the two peaks Y are magenta, the charge character R is cyan, and the background is in the design. Is printed in yellow. FIG. 2C is an enlarged view of the background wavy line X using a loupe. The wavy line X is a configuration in which minute characters are arranged in a wave shape, and the characters can be read. In addition, the characters themselves are composed of relatively large engraving cells unique to gravure printing, which are different from small dots by offset printing. Have been. For this reason, the character shape is different from that of intaglio printing or offset printing, and it is difficult for a forger to copy accurately even if a forger attempts to forge, and an effective forgery prevention effect can be provided.

(Embodiment 2) Next, a method for producing a printed matter having the same effect as in Embodiment 1 by using an electronic engraving machine having a low resolution will be described. A color original containing minute characters with a character height of 380 μm is separated into cyan, magenta, and yellow at a high resolution of 400 lines / inch or more by an electronic plate making device (scanner), and for example, yellow image data containing minute characters Is converted to chromacom format image data so that it can be recognized by an electronic engraving machine using a Heidelberg Prepress Helio-Klischograph K201. At this time, the image data is converted by changing the image area to four times in advance without changing the image resolution.
When the converted image data in the chromacom format is read by the electronic engraving machine after reducing the image area to 1/4, the pixel P having density information as shown in FIG. 'Is converted. When this image data is engraved on a gravure cylinder by the electronic engraving machine,
Engraving is performed as in 3 (b) engraving cell S ′. When this gravure printing plate is printed by a gravure printing machine, readable characters such as the character N 'in FIG. 3C can be printed, and by simultaneously perforating, a printed matter similar to that of the first embodiment can be produced.

[0011]

According to the present invention, gravure printing can clearly print even small characters having a character height of approximately 400 μm or less, so that a readable printed material can be provided. For this reason, even if a counterfeiter forges using offset printing, it is not possible to completely duplicate minute characters formed by cells, which is a feature of gravure printing. In other words, the presence / absence of a cell and the shape of the cell are decisive factors for determining the authenticity. Also, when copying the thing of the present invention,
The cell shape of the minute character is not accurately reproduced and is crushed, so that it is possible to prepare a genuine and fake discriminator, which is an effective forgery prevention means. In particular, since a large number of characters can be printed with small small characters having a character height of 400 μm or less for securities such as stamps and income stamps having a small printing area of 1935 mm2 or less, a large amount of information can be provided, and Since the characters are too small to be visually recognized, they can also be used as copy-forgery-inhibited patterns. In addition, since gravure printing alone can print minute characters having an anti-counterfeiting effect, it can be manufactured inexpensively and in a short period of time without using other plate types together.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a case where minute characters having a character height of 400 μm or less are printed by an electronic engraving machine manufactured by Heidelberg Prepress.

FIG. 2 is a plan view and an enlarged view of an embodiment of a stamp according to the present invention.

FIG. 3 is a schematic diagram of a case where minute characters having a character height of 380 μm are printed by an electronic engraving machine of Heidelberg Prepress Co., Ltd. according to the present invention.

[Explanation of symbols]

 P Pixel S Engraving Cell N Micro-Character T Paper K Stamp K 'Enlarged Stamp R Fee X Ground Pattern Y Mountain Z Punch P' Pixel S 'Engraving Cell N' Micro-Character

Claims (1)

[Claims] 1. A printed matter of securities, wherein fine characters having a character height of approximately 400 μm or less are printed by gravure printing on a relatively small print area.