JPH1134564A - Sheet with written concealing mark and method for reading the mark - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet with written concealing mark of a new constitution and a method for reading the mark. SOLUTION: The sheet 1 is obtained by printing a concealing mark 2 such as a character, graphic form or bar code with white or transparent ink containing ultraviolet absorbent on a base sheet 3 containing fluorescent agent. When the sheet 1 is irradiated with an ultraviolet light, the mark 2 absorbs the light, and the other surface is excited by fluorescence with the agent to develop color. Thus, its contrast becomes clear, and the mark 2 is observed to be blackened. Hence, this is read at information visually or by an optical reader.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper on which a secret mark for preventing forgery or the like is written and a method for reading the secret mark, which is used for certificates, securities, cash vouchers and the like. is there.

[0002]

2. Description of the Related Art Various countermeasures for preventing counterfeiting of documents such as certificates and securities have been proposed.

In the forgery prevention means, conventionally, a confidential mark displayed by characters, bar codes, or the like is printed with, for example, colorless and transparent fluorescent ink. In the case of characters, ultraviolet light is irradiated, and the fluorescence excited from the fluorescent agent is visually read to judge authenticity. The bar code information is read by reading the excited fluorescence.

[0004]

In recent years, base paper containing a fluorescent agent has been widely used in order to increase whiteness. For this reason, when hidden characters and the like are printed on such paper with colorless fluorescent ink as in the past, it is difficult to obtain a contrast between the hidden characters and the other surface, so that visual confirmation can be easily performed. Or an erroneous reading by an optical reader may occur. An object of the present invention is to provide a sheet on which a new security mark is written and a method for reading the security mark, which can solve the problem of the conventional configuration.

[0005]

According to the present invention, a confidential mark represented by characters, figures, bar codes, or the like is printed on a base paper containing a fluorescent agent with white ink or transparent ink containing an ultraviolet absorber. The present invention relates to a sheet on which a secret mark is written.

In this paper, the confidential mark is assimilated with the color of the paper and cannot be distinguished, and its existence is concealed. And when this paper surface is irradiated with ultraviolet light, the secret mark absorbs the ultraviolet light, and on the other surface, the fluorescent agent in the base paper excites the fluorescence, and therefore, the secret mark, under ultraviolet light, It looks dark against the surroundings and can be visually identified. Therefore, when an authentication mark is applied as the secret mark, the authenticity can be determined visually by irradiating ultraviolet light, and forgery can be prevented.

The secret mark can be read by irradiating the sheet with ultraviolet light and detecting the contrast of the reflected wave with an optical reader. By performing such mechanical reading as the secret mark, not only the authenticity of the secret mark is simply judged, but also the descriptive information displayed in a bar code or the like is mechanically detected, and for example, a password, a member number, or the like is detected. It can also read secret signs.

Here, phenyl salicylate, p-tert-
There are butylphenyl salicylate, p-octylphenyl salicylate and the like. Benzophenone UV absorbers include 2,4-dihydroxybenzophenone, 2-hydroxy
-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,2'-dihydroxy-4-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'- Dimethoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis (2-methoxy-4-hydroxy-5-benzoylphenyl) methane and the like. Furthermore,
Benzotriazole-based ultraviolet absorbers, cyanoacrylate-based ultraviolet absorbers and the like can be mentioned. Then, the secret mark is printed with a mixture of these ultraviolet absorbers with transparent ink or white ink.

As the white ink containing an ultraviolet absorber, a white ink containing titanium oxide (TiO ₂ ), which is an inorganic pigment, can be used. This titanium oxide also has an ultraviolet absorbing effect, and the white ink is a commercially available product, and has the advantage that it can be used as it is as a printing ink for confidential marking without the need to prepare an ultraviolet absorbing agent.

[0010]

FIG. 1 shows a sheet 1 on which a security mark 2 is written. Here, the base paper 3 used as the paper 1 contains a fluorescent agent in advance. A secret mark 2 is formed along the left and right edges in FIG. The secret mark 2 is printed with white ink or transparent ink containing an ultraviolet absorber. The security mark 2 is used as an authenticity determination mark. After the security mark 2 is printed on the base paper 3 in advance to form a special paper, necessary characters and the like are printed on the paper. And used as securities. In this configuration, since the base paper 3 contains a fluorescent agent,
The whiteness of the paper is remarkable. In addition, in this configuration, as shown in FIG. 1, the confidential mark 2 is assimilated with the color of the base paper 3 and cannot be distinguished, and its existence is concealed.

When this sheet is irradiated with ultraviolet light x as shown in FIG. 3, since the secret mark 2 contains an ultraviolet absorber, the ultraviolet light is absorbed. From the fluorescent agent, the fluorescent light y is excited to generate color.
For this reason, as shown in FIG. 2, the secret mark 2 looks dark against its surroundings under the ultraviolet light due to the contrast of the reflected wave, and can be visually distinguished. Therefore, by irradiating the secret mark 2 with ultraviolet light, the authenticity can be determined visually and the forgery can be prevented.

Instead of the visual judgment, the authenticity can be mechanically judged by irradiating the ultraviolet ray x and reading the reflected wave by the optical reader 5 as shown in FIG. In this case, the optical reader 5
By sequentially supplying a large number of securities and the like to the server, a large amount of authenticity judgment processing can be performed.

The confidential mark 2 may be used not only for preventing forgery but also for displaying various confidential information such as a password and a membership number. In this case, in the case of numerals and characters, the information can be read visually, but in the case of a mark such as a bar code that cannot be read visually, the information is read by an optical reading device. . In the case of a barcode, forgery by transfer is easy because the barcode is constituted by the thickness and the interval of the line element. However, as in the present invention, the barcode is normally displayed by the confidential mark 2 which cannot be visually recognized. The information can be read while effectively preventing forgery.

[0014]

According to the present invention, as described above, the secret mark 2 of characters, figures, bar codes, etc. is formed on the base paper 3 containing the fluorescent agent by using white ink or transparent ink containing an ultraviolet absorber.
When the paper 1 is irradiated with ultraviolet light x, ultraviolet light is absorbed in the secret mark 2, and on the other surface, the fluorescence y is excited by the fluorescent agent to form a color. Since the contrast becomes clear and the secret mark 2 looks dark, the information is read by the visual or optical reading device 5, so that the following effects are obtained.

1) It is possible to use base paper 3 containing a fluorescent agent to improve whiteness. 2) By using the secret mark 2 as an authentication mark, forgery can be easily determined by the visual or optical reader 5. 3) When a commercially available white ink containing titanium oxide is used, the preparation of an ultraviolet absorber is not required, and printing becomes easy.
Lower cost.

[Brief description of the drawings]

FIG. 1 is a plan view of a sheet 1 according to the present invention.

FIG. 2 is a plan view of the present invention showing a coloring state.

FIG. 3 is a conceptual diagram showing irradiation of ultraviolet light and light reception by an optical reader.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Paper 2 Security mark 3 Base paper 5 Optical reader

Claims (4)

[Claims] 1. A confidential mark which is printed on a base paper containing a fluorescent agent with white ink or a transparent ink containing an ultraviolet absorber in the form of characters, figures, bar codes, or the like. Written paper. 2. The paper according to claim 1, wherein said security mark is a mark for judging authenticity. 3. The white ink containing the ultraviolet absorbent,
2. The paper according to claim 1, wherein the paper is a white ink containing titanium oxide. 4. A paper in which a confidential mark is displayed on a base paper containing a fluorescent agent with a white ink or a transparent ink containing an ultraviolet absorber, such as characters, figures, bar codes, etc., is irradiated with ultraviolet light. A method for reading the security mark on a sheet on which the security mark is written, wherein the security mark is read by detecting the contrast of the reflected wave with an optical reader.