| 摘要 |
PROBLEM TO BE SOLVED: To provide the illegal use preventing method for a magnetic card which can effectively prevent the magnetic card from illegally being used. SOLUTION: For the illegal use preventing method for the magnetic card 10, trouble magnetism which exceeds ordinary residual magnetism is left partially in the magnetic recording area 14 of the magnetic card 10 to form a trouble area 16 where normal magnetic recording is disabled partially in the magnetic recording area 14. As an example, this trouble area 16 is formed by sequentially narrowing the magnetic recording area 14 of the magnetic card 10 according to the use rest of the magnetic card 10. |
