| 摘要 |
A magnetic recording medium having a non-magnetic substrate, a first magnetic layer composed mainly of magnetic powder and binder and formed on the non-magnetic substrate, and a second magnetic layer composed mainly of magnetic powder and binder and formed on the first magnetic layer is disclosed. In this case, the magnetic powder of the first magnetic layer is made of ferro-magnetic metal powder which has a specific surface area of 20 to 40 m2/g measured according to BET adsorption method, the first magnetic layer has coercive force Hc1 of 800 to 1500 Oe, residual magnetic flux density of 3000 to 5000 Gausses and a thickness of more than 2 mu , while the magnetic powders of the second magnetic layer is made of ferro-magnetic metal powder which has a specific surface area of 40 to 150 m2/g measured according to BET adsorption method, the second magnetic layer has coercive force Hc2 of 1000 to 2500 Oe, residual magnetic flux density of 2000 to 3000 Gausses and a thickness 0.1 to 2 mu , and the coercive forces Hc1 and Hc2 are selected to satisfy Hc1</=Hc2 .
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