| 摘要 |
PURPOSE:To enable broad-band signal recording of the magnetic recording medium by a method wherein a second magnetic layer of two layer structure is constituted of a component mainly consisting of magnetic powder of A.Fe12O19 (wherein A is a metal of one kind selected out of Ba, Sr, Pb, and Ca), or being replaced a part of Fe thereof with another element. CONSTITUTION:A first magnetic layer 32, the second magnetic layer 33 are formed in order on a nonmagnetic substrate 31. The first magnetic layer 32 has the direction of easy magnetization in the direction 34 of transference in relation to a magnetic head, and is mainly consisting of magnetic iron oxide, chrome oxide, a magnetic metal body, etc. While the second magnetic layer 33 has the direction of easy magnetization in the perpendicular direction to the substrate 31 face, and is mainly consisting of magnetic powder of Ba.Fe12O19. From the characteristic (the output level) of the magnetic recording medium having structure like this and the result of measurement (sigma1, sigma2 are thickness of the first, the second magnetic layers, Hc1 and Hc2 are coercive forces of the layers thereof, S is the ratio of the angle shapes of the M-H loop in the perpendicular direction to the second layer) of the magnetic recording medium having single layer structure, to enable to attain rapid enhancement of broad-band output only by forming the second magnetic layer of Ba.Fe12O19 can be confirmed. |
