JPH045341Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a counterfeit-proof plastic card used as a various certification card such as a credit card or a bank card.

BACKGROUND OF THE INVENTION In order to prevent counterfeiting of this type of certification card, it is desirable to provide a means for determining potential authenticity of the card. Conventional methods for such identification include, for example, adding a watermark to the card itself, inserting a password into a part of the card using a special material that can be detected by infrared rays, or embedding a magnetic material that can be detected magnetically. Various methods have been proposed. However, when using these methods, not only is the production of the card complicated and costly, but also the cost of the detection device is high in the case of infrared detection or magnetic detection. The reality is that most of these methods have not yet been put into practice because the detection operation is also cumbersome.

On the other hand, as a simple means of preventing counterfeiting, ink containing a fluorescent substance has been applied to the card surface to hide hidden patterns and characters that are hidden under visible light and cannot be seen under ultraviolet rays. It is also used as a printing layer (for example, in 1983)
-159154, Utility Model No. 56-563, etc.).

Problems that the invention aims to solve However, those who attempt to counterfeit cards usually try to detect in advance the existence and form of anti-counterfeiting measures applied to genuine cards. Considering that forming hidden patterns using fluorescent substances is widely applied not only to identification cards but also to various other products, counterfeiters can use ultraviolet rays to prevent counterfeiting. It is quite possible to detect the presence or absence and specific aspects of this.

However, in the case of cards such as conventional products that have anti-counterfeiting measures such as the above-mentioned hidden patterns applied to the surface of the card, it is easy to detect this, and therefore, it is easily detected by a counterfeiter. It cannot be denied that the possibility is high. Therefore, although it is primarily important for counterfeit prevention means to prevent detection of the counterfeit prevention means, the above-mentioned conventional products cannot necessarily be said to be preferable.
In addition, it is important that anti-counterfeiting measures are difficult to imitate even if the counterfeit prevention measures are discovered in the second place, but it is also important that counterfeit prevention measures are difficult to imitate if the counterfeit prevention measures are discovered. As long as the printed layer is formed by using a printing layer such as the above, it is not impossible for a person who intends to counterfeit it to imitate it using a relatively simple printing means, and in fact, it can be done relatively easily. . For this reason, the conventional products have not necessarily been able to highly avoid the possibility of being counterfeited.

In view of the above-mentioned background, this idea was developed to firstly make it difficult to detect the presence or absence of anti-counterfeiting measures, and secondly to make it difficult to counterfeit even if they are detected. The third object is to make the card easy to manufacture by card manufacturers who have limited predetermined equipment, to be able to mass-produce it well, and to provide it at low cost.

Means for Solving the Problems This invention aims to achieve the above-mentioned purpose by creating a transparent synthetic resin layer containing an ultraviolet absorber on both sides of a fluorescent core layer consisting of an opaque synthetic resin layer containing a fluorescent brightener. The object of the present invention is to provide a counterfeit-preventing plastic card in which a coating layer made of a resin layer is integrally laminated.

Embodiments This invention will be described below with reference to illustrated embodiments.

The plastic card according to this invention has one fluorescent core layer 1 made of opaque synthetic resin, and transparent covering layers 3 made of synthetic resin that are fully laminated and integrated on both sides of the fluorescent core layer 1. Consisting of On one or both sides of the core layer 1, a display print layer 2 for displaying necessary characters for information transmission is formed, and the above-mentioned transparent coating layer 3 is formed to cover the print layer 2.

The fluorescent core layer 1 consists of an opaque synthetic resin layer mixed with a fluorescent whitening agent and colored in an appropriate color.
For example, polyvinyl chloride resin, acrylonitrile-butadiene-styrene resin, polycarbonate resin, etc. mixed with a fluorescent brightener and formed into a sheet shape are used. Fluorescent brighteners are additives that eliminate the yellow tinge of plastic products and give them transparency and brightness, such as those with compositions such as coumarins, naphthotriazolylstilbenes, benzoxazoles, and benzimidazoles. is used, and is mixed in an amount of at least 0.05 parts by weight per 100 parts by weight of the resin. In this case, if the amount of the fluorescent whitening agent mixed is less than 0.05 part by weight, blue-violet fluorescence is less likely to occur significantly under irradiation with ultraviolet rays. Further, although the fluorescent core layer 1 is usually colored white, it may be colored yellow or other colors. Of course, it is desirable that the core layer 2 has a bright color so that the printed layer 2 such as letters can be easily seen.

The transparent coating layer 3 is made of a transparent synthetic resin layer mixed with an ultraviolet absorber, and is formed into a film by, for example, polyvinyl chloride resin, polycarbonate resin, etc. mixed with an ultraviolet absorber. The ultraviolet absorber is an additive that prevents photodeterioration of plastic products, such as those of hydroxybenzophenone type, benzotriazole type, salicylic acid ester type, etc. at least
Contains 0.05 parts by weight or more. In this case, if the amount of the ultraviolet absorber mixed is less than 0.05 part by weight, the excited luminescence of the opaque fluorescent core layer 1 cannot be sufficiently suppressed when ultraviolet rays are irradiated from the front or back side of the card. . Therefore, in the card according to this invention, the core layer emits blue-violet fluorescence at the end surface only when ultraviolet rays are irradiated from the peripheral end surface of the card.

Note that the means for laminating and integrating the opaque fluorescent core layer 1 and the transparent coating layers 3, 3 containing an ultraviolet absorber on both sides may be to bond each layer with an adhesive, but a general method is used. They are closely bonded to each other by means of heat fusion.

The card of the above embodiment is mainly used for various identification purposes, and the unique fluorescent core layer 1, which is opaque on both the front and back sides under visible light such as daylight, is Depending on the color, for example, it is observed as white. Moreover, even if either the front or back surface is irradiated with ultraviolet rays, etc., the appearance of both the front and back surfaces will only change to a slightly darker color due to the ultraviolet absorption effect of the transparent coating layers 3, 3, and there will be no special characters or the like. Shows no apparent change. However, when the peripheral edge of the card is irradiated with ultraviolet rays, the peripheral edge of the fluorescent core layer 1 emits blue-purple light, or changes to a whitish bright color, and when observed from the edge. It is possible to determine whether the card is genuine.

Effects of the invention As explained in the operation of the above-mentioned embodiments, even if the front or back side of the card is irradiated with ultraviolet rays, the appearance of the card changes to a darker color in the transparent coating layer containing the ultraviolet absorber. The overall appearance is slightly darkened, and special hidden patterns or hidden characters do not come to light. Therefore, it is difficult to detect the fact that the card is provided with an authentication means for preventing counterfeiting. That is, it has excellent prevention functionality in detecting the presence or absence of a counterfeit prevention means. On the other hand, those who know the structure of the card know that by irradiating the peripheral end face with ultraviolet rays, a blue-purple emission or a bright color change appears on the end face of the core layer, and a dark color change of the transparent coating layer on the front and back sides. , the authenticity of the card can be determined extremely easily based on the mutual contrast.

Furthermore, even if the presence of the fluorescent core layer is detected by a person attempting to counterfeit,
The card according to the present invention is difficult to imitate. That is, in the anti-counterfeit card of the present invention, a fluorescent brightener is mixed in the core layer that constitutes the main body of the card, and an ultraviolet absorber is mixed in the coating layer that covers both sides of the core layer. Therefore, in addition to the difficulty in obtaining from the market colored synthetic resin sheets containing a fluorescent whitening agent that are similar to the core layer, it is also difficult to obtain from the market a resin film containing an ultraviolet absorber that is similar to the coating layer. Moreover, the work of laminating and integrating these layers is extremely difficult unless special laminating and bonding equipment is available, and counterfeiting by unauthorized persons is difficult, thereby ensuring even higher safety.

On the other hand, card manufacturers who have the necessary equipment can manufacture cards by continuously laminating a transparent resin film or sheet containing an ultraviolet absorber on an opaque resin sheet containing a fluorescent brightener. It is easy to manufacture, has excellent mass productivity, and can be provided at low cost.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of this invention. 1... Opaque fluorescent core layer, 3... Transparent coating layer.

Claims (1)

[Scope of utility model registration request] An anti-counterfeiting plastic made of a fluorescent core layer made of an opaque synthetic resin layer mixed with a fluorescent whitening agent, and a transparent coating layer made of a transparent synthetic resin layer mixed with an ultraviolet absorber on both sides of the layer. card.