JPH1021528A - Magnetic card and its use method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent alteration of a magnetic card by forming a first magnetic layer on a part of a substrate and forming a second magnetic layer comprising magnetic particles and an org. molecular compd. having lower melting point than the softening points of the substrate and the first magnetic layer, on the first magnetic layer. SOLUTION: The magnetic card is heated to 200 deg.C, kept in a magnetic field to orient the second magnetic layer 4 in one direction, and then cooled. Then a magnetic head (which generates 5KG magnetic field) is used for recording in the longitudinal direction of the card by FM method. When the recorded information is read by using a magnetic card reader, the whole information can be read. Then the card is cooled to solidify the org. polymer compd. When the recorded information is to be read by using a magnetic card reader, the information in the area irradiated with laser beam can not be read.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a magnetic card and a method of using the same, and more particularly, to a magnetic card having a function of preventing alteration and a method of using the same.

[0002]

2. Description of the Related Art A magnetic card used as a voucher such as a ticket, a telephone card, a prepaid card, or the like is rewritten with a predetermined device by using a predetermined device each time the magnetic card is used. It is used.

In order to prevent such alteration, these magnetic cards are provided with a protective layer on the magnetic layer or a multilayered magnetic layer.

[0004] However, with the spread of magnetic cards, device technology for reproducing and recording information on magnetic cards has also been developed, and it has become possible to easily read recorded information and even write information. Specifically, every time a magnetic card is used, all information including new information is rewritten so that it is overwritten on old information. Therefore, if there is a device that records and reproduces information, it can be easily rewritten. Can be performed. For this reason, in recent years, alterations of magnetic cards have increased.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a magnetic card which eliminates the above-mentioned drawbacks and is excellent in preventing alteration such as overwriting and rewriting recorded magnetic information, and a method of using the same. .

[0006]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has been made as a result of an investigation. This prevents alteration.

That is, according to the present invention, a first magnetic layer is provided on at least a part of a base, and an organic material having a melting point lower than the softening temperature of the base and the first magnetic layer is provided on the first magnetic layer. A magnetic card provided with a second magnetic layer comprising a molecular compound and magnetic particles.

The present invention also provides the method of using the magnetic card, wherein the second magnetic layer is heated to dissolve the organic polymer compound, and then cooled to make re-recording impossible. is there.

A first magnetic layer having a high coercive force is provided in an arbitrary shape on a part or the entire surface of the main surface of the base of the magnetic card, and the base and the first magnetic layer are provided on the first magnetic layer. 1
Forming a second magnetic layer comprising an organic polymer compound having a melting point lower than the softening temperature of the magnetic layer and magnetic particles;
The magnetic information is recorded on the magnetic layer. After using the magnetic card,
When the substrate or the first magnetic layer is heated at a temperature that does not cause softening deformation, the organic polymer compound dissolves, the magnetic particles are not fixed, and the magnetic particles are affected by the first magnetic layer having a high coercive force. Align. Thereafter, the substrate is cooled,
If the organic polymer compound is solidified and the magnetic particles are fixed, overwriting on the magnetic card becomes impossible.

[0010] The softening temperature generally varies depending on the rate of temperature rise, the degree of polymerization, and the like. For example, the softening temperature of polyimide is 490
C. to 500.degree.

[0011] The second comprising an organic polymer compound and magnetic particles
Is preferably at least 10 ° C. lower than the softening temperatures of the substrate and the first magnetic layer.

When the melting point of the organic high molecular compound forming the second magnetic layer is 50 ° C. or less, heating is performed without heating.
There is a possibility that the organic polymer compound is dissolved and cannot be used. Therefore, the organic polymer compound is 5
It is desirable to have a melting point of 0 ° C. or higher.

[0013]

1 to 3 show an embodiment of the present invention.
This will be described with reference to FIG.

FIG. 1 is a sectional view of a magnetic card according to the present invention, showing a state before information is recorded. FIG. 2 is a cross-sectional view of the magnetic card of the present invention showing a state after information has been recorded. FIG. 3 is a cross-sectional view of the magnetic card of the present invention showing a state where the organic polymer compound is dissolved by heating by laser irradiation. The arrows in the figure indicate the orientation direction.

As shown in FIG. 1, a magnetic card 1 has a first magnetic layer 3 formed on a main surface of a base 2 made of polyethylene terephthalate (hereinafter referred to as PET) resin, and a second magnetic layer 3 formed thereon. Is formed, and a protective layer 5 is further formed thereon.
Is formed.

The first magnetic layer 3 was prepared by mixing a samarium-cobalt magnetic powder (SmCo ₅ ) with a resin and a solvent at the following ratio to prepare a magnetic paint. -Magnetic powder 100 parts by weight-Resin (vinyl chloride-vinyl acetate copolymer) 6 parts by weight (polyurethane) 9 parts by weight-Solvent (methyl ethyl ketone) 60 parts by weight (cyclohexanone) 60 parts by weight (toluene) 60 parts by weight

The obtained magnetic coating material was applied on the substrate 2 so as to have a coating thickness of 10 μm, and dried to form a coating.

The second magnetic layer 4 was prepared by mixing barium ferrite magnetic powder having a predetermined composition with paraffin and a solvent to prepare a magnetic paint.・ 40 parts by weight of magnetic powder ・ 60 parts by weight of paraffin ・ 100 parts by weight of solvent (polyethylene glycol)

The obtained magnetic paint is applied on the first magnetic layer 3
Perform coating so as to have a coating thickness of 30 μm, dry,
Formed.

The magnetic card thus obtained is
After heating to 0 ° C., the second magnetic layer 4 was oriented in the same direction in a magnetic field, and cooled.

Next, recording was performed in the longitudinal direction by the FM method using a magnetic head (a generated magnetic field of 5 kG) (the state shown in FIG. 2). When the recorded information was read using a magnetic card reader, all the information could be read.

Next, a part of the portion where the magnetic information was recorded was heated to 200 ° C. by laser irradiation to dissolve the organic polymer compound. As shown in FIG. 3, the magnetic particles 6 are aligned under the influence of the first magnetic layer 3 having a high coercive force.
Thereafter, the mixture was cooled to solidify the organic polymer compound. When the recorded information was read using a magnetic card reader, the information of the laser irradiation part could not be read.

Further, another information is recorded by using a magnetic head, and the recorded information is read by using a magnetic card reader. As a result, the information of the laser irradiation part cannot be read, and the information of the laser irradiation part cannot be read. Has not been recorded.

[0024]

As described above, according to the present invention, it has become possible to provide a magnetic card excellent in prevention of alteration such as overwriting and rewriting recorded magnetic information and a method of using the same.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a magnetic card of the present invention showing a state before information is recorded.

FIG. 2 is a cross-sectional view of the magnetic card of the present invention showing a state after information has been recorded.

FIG. 3 is a cross-sectional view of the magnetic card of the present invention showing a state where the organic polymer compound is dissolved by heating by laser irradiation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic card 2 Base 3 First magnetic layer 4 Second magnetic layer 5 Protective layer 6 Magnetic particles

Claims (2)

[Claims] 1. An organic polymer compound having a melting point lower than the softening temperatures of the base and the first magnetic layer, wherein a first magnetic layer is provided on at least a part of the base. A magnetic card comprising a second magnetic layer made of particles. 2. The method for using a magnetic card according to claim 1, wherein the second magnetic layer is heated to dissolve the organic polymer compound, and then cooled to make recording impossible.