| 摘要 |
<p>PURPOSE:To obtain high output in a wide wavelength region by providing the laminated magnetic layer which consists of an upper layer contg. plate-shaped hexagonal ferrite powder having the axis of easy magnetization perpendicular to the plate-shaped plane and a lower layer contg. magnetic metallic powder and in which the coercive force in the direction perpendicular to the magnetic layer is higher with the upper layer than with the lower layer. CONSTITUTION:The laminated magnetic layer having the upper layer formed by dispersing the powder of the plate-shaped hexagonal ferrite having the axis of easy magnetization perpendicular to the grannular plate-shaped plane and 0.03- 0.2mu average partucle size and having 400-2,000Oe coercive force, for example, barium ferrite powder in a binder resin and orienting the axis of easy magnetization perpendicularly to the plane of the magnetic layer and the lower layer contg. the magnetic metallic powder is formed on the base body. The laminated structure in which the ratio of the coercive forces of the upper/lower layers respectively in the direction perpendicular thereto is 1.1-1.5 is thus obtd. and the magnetic recording medium having a large squareness ratio in the perpendicular direction, the large output in a wide region from a short wavelength region to a long wavelength region and good surface smoothness is obtd.</p> |
