MAGNETIC RECORDING MEDIUM AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To provide a recording medium which has information allowing various changes of read output levels and waveforms and allows the sure identification from other recording media by incorporating magnetic materials at prescribed coarse and dense patterns in a second magnetic layer and incorporating the magnetic materials at patterns consisting of a density half or twice the coarse and dense patterns of the second magnetic layer into a third magnetic layer 3c. SOLUTION: The second magnetic layer 3b constituting magnetic recording layers 3 contain the magnetic materials in the prescribed coarse and dense patterns and the third magnetic layer 3c also contain the magnetic materials in the prescribed coarse and dense patterns, respectively holding the fixed information. The density of the coarse and dense patterns of the second magnetic layer 3b and the coarse and dense patterns of the third magnetic layer 3c are related so as to be halved or doubled with each other. At least, either of the magnetic materials contained in the second magnetic layer 3b and the magnetic materials contained in the third magnetic layer 3c is so formed that its coercive force is equal to or greater than the coercive force of the magnetic materials contained in the first magnetic layer 3a.