| 摘要 |
PURPOSE:To ensure satisfactory electromagnetic transducing characteristics in high- and low-frequency bands and satisfactory durability by interposing a nonmagnetic layer between a substrate and a magnetic layer consisting of two layers, contg. a specified ferromagnetic metal powder in one of the layers and having a prescribed total thickness and by regulating the difference in coercive force between the upper and lower layers to a prescribed value or below. CONSTITUTION:Magnetic layers 3, 4 are laminated on a nonmagnetic substrate 1 in <=0.3mum total thickness and ferromagnetic metal powder consisting of 100 pts.wt. Fe atoms, 2-10 pts.wt. Al atoms and 1-8 pts.wt. rare earth element is selectively incorporated into one of the layers 3, 4. The coercive force of the upper layer 3 is 1,700-2,400Oe, that of the lower layer 4 is 1,600-2,200Oe and the difference in coercive force between the layers 3, 4 is >=100Oe. A nonmagnetic layer 2 having 0.2-2mum thickness is interposed between the substrate 1 and the magnetic layer 4. The objective magnetic recording medium having satisfactory electromagnetic transducing characteristics in high- and low-frequency bands, satisfactory overwriting characteristics and running durability can be obtd. |
