JP3016620B2 - Information recording medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording medium, such as an optical disk or an optical card, having a function of preventing unauthorized tampering or a function of indicating that the device has been peeled and destroyed.

[0002]

2. Description of the Related Art In recent years, as information recording media capable of efficiently handling a wide variety of information, for example, optical disks,
Many information recording media for optically recording and reproducing information, such as optical cards and optical tapes, have been proposed. An optical information recording medium using a recording / reproducing method based on such an optical principle has a large recording capacity as compared with the size of the medium. Therefore, its application range is wide, and it is expected to be widely used as a portable personal information medium such as a medical chart card, a credit card, a cash card, an identification card, a driver's license, and the like.

[0003]

Among such information recording media, in particular, personal information relating to privacy is often recorded on a portable card-shaped recording medium, so that privacy protection and confidentiality protection are maintained. From the viewpoint, it is demanded to have a falsification prevention function. In addition, such an information recording medium often cannot be easily recognized visually, such as when it is slightly peeled off, and the use of the medium continues without being noticed,
Peeling proceeded, sometimes leading to loss of information.

An object of the present invention is to solve such a problem, and an object of the present invention is to prevent information from being tampered with and to easily recognize visually that peeling-off and destruction have occurred. To provide a medium.

[0005]

SUMMARY OF THE INVENTION The present invention provides a polymethylmethacrylate.
In an information recording medium in which a recording layer containing an organic dye dye, an adhesive layer containing an ethylene vinyl acetate resin adhesive, and a back substrate made of polycarbonate are laminated in this order on a transparent substrate made of tacrylate , a phenol resin is used. Layers and
Particle size of 30 to 4 disposed in contact with the phenol resin layer
A layer containing 0 μm microcapsule leuco dye
A color changing member layer between the recording layer and the adhesive layer and at least one between the adhesive layer and the backing substrate, wherein the color changing member layer separates the recording layer and the adhesive layer, or An information recording medium characterized in that the microcapsules are destroyed and discolored by peeling of the adhesive layer and the back substrate.

In the information recording medium of the present invention, if the recording layer and the adhesive layer, the adhesive layer and the back substrate, or the recording layer and the back substrate are peeled off for the purpose of falsification, the color-changing member layer is discolored. You can see at a glance that it has been tampered with. Furthermore, when the recording layer and the adhesive layer, the adhesive layer and the back substrate, or the peeling between the recording layer and the back substrate occur due to an accident, the discolored member layer is similarly discolored, so that the accident part can be found at a glance, Quick response to accident products

In the present invention, as the color-changing member layer, a layer in which microcapsules are destroyed upon peeling and develop color is used.

Hereinafter, examples of the layer structure of the information recording medium of the present invention will be described with reference to the drawings. 1 to 3 are schematic partial cross-sectional views showing an embodiment of the layer configuration of the information recording medium of the present invention.

The information recording medium illustrated in FIG. 1 is formed by sequentially laminating a recording layer 2, a color changing member layer 3, an adhesive layer 4, and a back substrate 5 on a transparent substrate 1 having desired irregularities. When the recording layer 2 and the color changing member layer 3 are directly laminated as illustrated in FIG.
Particularly, it is excellent in that the peeling of the interface between the recording layer 2 and the adhesive layer 4 can be detected.

The information recording medium illustrated in FIG. 2 has a structure in which the color changing member layer 3 and the adhesive layer 4 of the information recording medium illustrated in FIG. When the layers are laminated as illustrated in FIG. 2, peeling of the adhesive layer 4 and the back substrate 5 can be detected. In the case where one color-changing member layer 3 is provided, including the case described above, the substrate 1, the recording layer 2, the adhesive layer 4, and the back substrate 5
Discoloration member layer 3 on the interface with the smallest adhesive strength and easy to peel
Is desirably provided.

The information recording medium illustrated in FIG. 3 has a structure in which the color changing member layer 3 of the information recording medium illustrated in FIG. 1 is further provided between the adhesive layer 4 and the back substrate 5. This figure 3
A plurality of color-changing member layers 3 may be provided as shown in FIG. 1, and in this case, it is excellent in that any peeling of the interface can be detected.

[0012]

The present invention will be described in more detail with reference to the following examples.

First, a track groove was formed in a polymethyl methacrylate film (manufactured by Nitto Resin Co., Ltd.) having a thickness of 0.3 mm by a hot press method to obtain a transparent substrate 1. Next, an organic dye was spin-coated on the track groove surface to form a recording layer 2 having a thickness of about 900 angstroms. Next, an ethylene vinyl acetate resin adhesive was overlapped so as to be in contact with the recording layer 2 to form an adhesive layer 4.

On the other hand, a phenol resin was applied to the surface of a 0.3 mm thick polycarbonate film (back substrate 5).
Further, a microcapsule leuco dye having a particle diameter of 30 to 40 μm dissolved and dissolved in a hydrocarbon-based oil and having a particle size of 30 to 40 μm is applied.
By pressing with a hot roll of 10 ° C., the transparent substrate 1,
An information recording medium (optical card) as shown in FIG. 2 in which the recording layer 2, the adhesive layer 4, the color changing member layer 3, and the back substrate 5 were sequentially laminated was obtained.

When trying to peel off this optical card,
The discoloration member layer 4 changed color. Due to this discoloration, restoration after complete peeling was impossible.

[0016]

As described above, in the information recording medium of the present invention, it is impossible to deliberately remove the card and falsify the data because there is a portion that cannot be restored when the information is peeled off. Become. In addition, even when the card is peeled off in an accident, the user can know at a glance this, so that accidental use of the accidental product can be prevented. These functions are peculiar functions suitable for an information recording medium, and thus become an information recording medium such as an optical card and an optical disk which is very useful in practice.

[Brief description of the drawings]

FIG. 1 is a schematic partial cross-sectional view showing one embodiment of a layer configuration of an information recording medium of the present invention.

FIG. 2 is a schematic partial sectional view showing another embodiment of the layer configuration of the information recording medium of the present invention.

FIG. 3 is a schematic partial sectional view showing another embodiment of the layer configuration of the information recording medium of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transparent substrate 2 Recording layer 3 Discoloration member layer 4 Adhesive layer 5 Back substrate

Claims (1)

(57) [Claims] A recording layer containing an organic dye on a transparent substrate made of polymethyl methacrylate , and ethylene vinyl acetate.
Adhesive layer containing resin adhesive and polycarbonate
In the information recording medium in which the back substrate is laminated in this order, the phenol resin layer and the phenol resin layer are in contact with each other.
Microcapsules having a particle size of 30 to 40 μm
A color-changing member layer comprising a layer containing a leuco dye, at least one of between the recording layer and the adhesive layer and between the adhesive layer and the back substrate, wherein the color-changing member layer comprises the recording layer and the adhesive layer An information recording medium characterized in that the microcapsules are destroyed and discolored by peeling off the adhesive layer or the adhesive layer and the backing substrate.