JPH0463448B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention provides a cash dispenser card,
Concerning magnetic cards that require confidentiality such as ID cards.

Conventional magnetic cards will be explained with reference to FIGS. 1 and 2.

The magnetic card shown in FIG. 1 has a magnetic film 2 for magnetic recording and reproducing made of a magnetic material with high coercive force provided on a non-magnetic substrate 1 such as plastic, and a protective film 3 for program concealment and a protective film 4 on top of the magnetic film 2. is formed.

The magnetic card shown in FIG. 2 is an improved example of the one shown in FIG. 1, but instead of the protective film 3, a magnetic film 3' is provided, which has a lower coercive force than the magnetic film 2 but allows writing. ′ by writing a fake program to
The magnetic film 2 cannot be read using a normal reading method.

However, in the magnetic card shown in FIG. 1, if a magnetic field is applied from the front side to saturate the protective film 3, the information content can be easily determined. In the magnetic card shown in Figure 2, fake programs and true programs are mixed, but since the true program also appears, the information content can be determined by waveform analysis, which poses a problem with confidentiality. .

The present invention aims to solve these problems by shielding information written on a magnetic film for magnetic recording and reproducing with a magnetic protective film for secrecy provided on the magnetic film, and further, by shielding information written on a magnetic film for magnetic recording and reproducing with a magnetic protective film for secrecy provided on the magnetic film. The idea is to maintain the confidentiality of true information by providing a magnetic film with high coercive force on the magnetic film and writing false information on this magnetic film.

FIG. 3 shows an embodiment of the invention in cross section.

As the substrate 1, PET with a thickness of 150 to 300 μ is used, on which a magnetic film 2 with a coercive force of 1500 to 3000 Oe and a thickness of about 6 μ is formed, and on top of that a magnetic film 2 with a coercive force of 30 Oe or less and a thickness of about 10 μ is used. A protective film 3 is formed. A magnetic film 5 having a coercive force of 500 to 1000 Oe and a thickness of several μm is further formed thereon. 4 is a protective film having a thickness of 1 to 3 μm, but the protective film 4 can be omitted by using the magnetic film 5 also as a protective film. The figure is a longitudinal cut of a magnetic card in the area of the magnetic film 2, and the magnetic film 2 is normally formed in a partial area of the substrate 1, so the secrecy protective film 3 and the magnetic film are 5 etc., it is sufficient if they are also formed on the magnetic film 2.

To write to the magnetic card, first, necessary information is written on the magnetic film 2 by a recording means having sufficient writing ability. Since this information will also be written to the magnetic film 5, next the write current is reduced to such an extent that it can be written only to the magnetic film 5.
False information is written on the magnetic film 5. Reading may be performed while bringing the magnetic film 5 into a saturated state using a magnetic field from a magnet or the like.

According to such a magnetic card, the information written on the magnetic film 2 is shielded by the secrecy protective film 3, so that only the false information written on the magnetic film 5 can be detected using normal methods such as a magnetic pattern observation device. will appear. Moreover, since the magnetic film 5 has a function no different from that of magnetic cards used up to now, the existence of the magnetic film 2 is never known. Therefore, the magnetic card according to the present invention has excellent confidentiality and
This will have a significant effect in contributing to the field of magnetic card usage, which is becoming increasingly important as the world moves to a cashless society.

[Brief explanation of the drawing]

FIGS. 1 and 2 are sectional views of a conventional magnetic card, and FIG. 3 is a sectional view of an embodiment of the present invention. In the figure, 1 is a substrate, 2 is a magnetic film for magnetic recording and reproducing, 3 is a concealing protective film, 4 is a protective film, and 5 is a magnetic film.

Claims (1)

[Claims] 1. In a magnetic card in which a concealing protective film made of a soft magnetic material is provided on a high coercive force magnetic film for magnetic recording and reproduction on a magnetic card substrate, a concealing protective film made of a soft magnetic material is provided on the concealing protective film with a smaller coercive force than the high coercive force magnetic film. A magnetic card characterized by being provided with a writable magnetic film.