| 摘要 |
PURPOSE:To obtain the excellent corrosion resistance of a recording layer consisting of a thin rare earth-transition metal amorphous alloy film having the axis of easy magnetization in the direction perpendicular to the film plane by providing thin anodic oxide films on both surfaces of said recording layer thereby protecting the recording layer. CONSTITUTION:The 1st protective layer 3 on the base body 1 side of the recording layer 4 consisting of the thin rare earth-transition metal amorphous alloy film having the axis of easy magnetization in the direction perpendicular to the film plane out of the protective layers 3, 5 formed respectively on both front and rear surfaces of the layer 4 formed on the substrate 1 is constituted with the thin oxide film provided by the anodic oxidation of the same thin alloy film as the layer 4 in an aq. soln. The 2nd protective layer 5 on the surface of the layer 4 on the side opposite from the body 1 is constituted with the thin oxide film provided by the anodic oxidation of the thin alloy film surface constituting the layer 4 in the aq. soln. A thin light transmittable film 2 is provided between the layer 3 and the body 1. The layer 5 is formed of the thin oxide film of the base itself of the layer 4 and therefore defects such as pinholes are eliminated and the adhesiveness is good. Since the layer 3 is formed of the anodic oxide of the same component as the component of the base for the layer 4, said layer has less defects such as pinholes. The cracking in the stage of forming the layer 3 is prevented by providing the film 2 between the layer 3 and the body 1. |
