MAGNETIC RECORDING MEDIUM AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To provide a magnetic recording medium and a method for manufacturing the magnetic recording medium having fixed information capable of variously changing an output level and a waveform in reading by a magnetic head and capable of sure distinction between an other magnetic recording medium and this magnetic recording medium, wherein such fixed information is difficult to be recognized by externals and dishonest acts such as forgery or alteration can be prevented. SOLUTION: This magnetic recording medium 1 consists of a magnetic recording layer 3 comprising a first magnetic layer 3a, a second magnetic layer 3b and a third magnetic layer 3c which are laminated on a substrate in this order. The second magnetic layer 3b includes a magnetic material with a prescribed coarse and fine pattern and the third magnetic layer 3c includes the same magnetic material with the reverse pattern on the coarse and fine pattern of the second magnetic layer 3b. The ratio A/B of coercive force A of the magnetic material included in the second magnetic layer 3b to coercive force B of the magnetic material included in the third magnetic layer 3c is specified to be <=1/3 or >=3.