| 摘要 |
PURPOSE:To obtain a magnetic recording medium having an excellent reproducing output at all bands with a low level of noise, by setting the specific surface area, the coercive force, the residual magnetic flux density, etc. within a specific range respectively for the magnetic powder of iron oxide of each of two magnetic layers. CONSTITUTION:The magnetic powder of iron oxide having 18-25m<2>/g specific sirface area and obtained by a BET process is coated on a nonmagnetic substrate 1 to obtain the 1st magnetic layer which has 250-400 oersted coercive force HC1 and 1,600-2,000G residual magnetic flux density. Then either one or both of the magnetic powder of iron oxide having 28-45m<2>/g specific surface area and obtained by the BET process and the magnetic powder of iron oxide coated with Co are coated on the layer 4 to obtain the 2nd magnetic layer 5 which has 300-900 oersted coercive force HC2. The HC2 of the layer 5 is set larger than the HC1 of the layer 4. |
