| 摘要 |
PURPOSE:To enable high density recording by laminating a magnetic layer contg. magnetic iron oxide powder and oriented in the horizontal direction and a magnetic layer contg. magnetic iron oxide powder having Co in the surface layer and oriented in the vertical direction. CONSTITUTION:A magnetic coating consisting essentially of magnetic iron oxide powder of gamma-Fe2O3, gamma-Fe2O3 contg. Co or the like, a binder resin and a solvent is applied to a substrate such as a polyester film and dried after carrying out orientation in a magnetic field so as to provide >=0.7 squareness in the horizontal direction of the resulting magnetic layer. A magnetic coating consisting essentially of uniaxially anisotropic needlelike magnetic powder obtd. by forming a surface layer contg. chiefly Co on magnetic iron oxide powder as nuclear crystals, a binder resin and a solvent is then applied to the magnetic layer and dried while carrying out orientation in the vertical direction in a vertical magnetic field so as to provide >=0.4 squareness. |
