| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic card whose security is higher and which is provided with practicality and economical efficiency and to provide its magnetic recording and reproducing method. SOLUTION: A magnetic recording layer 4 which comprises lateral stripe- shaped (bar code-shaped) uneven parts is formed in the movement direction in the recording and reproducing operation on an information recording track 6 of a magnetic card 1. The magnetic recording layer 4 uses a powder by a magnetic substance such as an Sm-Co-Al-based alloy or the like whose coercive force is at 4 kOe or higher. In a recording and reproducing method, two or more kinds of recording outputs, or their difference, of magnetic recording information corresponding to the uneven parts on the magnetic recording layer 4 are detected. Alternatively, reproducing outputs, or their difference, after or before and after a unidirectional magnetic field is applied to the magnetic recording information are detected. Then, the obtained difference between the reproducing outputs is added to the magnetic recording layer 4 as information. |
