| 摘要 |
PURPOSE:To improve corrosion resistance and surface smoothness of a magnetic recording medium, by laminating the first magnetic layer containing oxide magnetic powder, and the second magnetic layer containing metallic magnetic powder having a specific saturation magnetizing quantity, on a base body. CONSTITUTION:The first magnetic layer is formed by applying a magnetic painting material consisting of oxide magnetic powder (example: gamma-Fe2O3) whose coercive force is 400-600 oersteds, a binder and an organic solvent, on a base body of a polyester film, etc., and drying it. Subsequently, the second magnetic layer is formed by applying a magnetic painting material consisting of metallic magnetic powder (example: Fe, Co) whose saturation magnetizing quantity is 140emu/g and whose coercive force is 600-1,200 oersteds, a binder and an organic solvent, on said first magnetic layer, and drying it. In this way, the drop- down rate of residual magnetic flux density, and surface roughness become small enough, and corrosion resistance and surface smoothness of the magnetic layer are improved. |
