| 摘要 |
PURPOSE:To obtain a magnetic tape having superior magnetic property by a method having the steps of preparing a cobalt-containing magnetic iron oxide which contains hydroxides of at least one of Cu, Al, Ti, Zr, Sn, V, Nb, Sb, Cr, Mo, W and Ni and effecting a vapor treatment on the iron oxide. CONSTITUTION:As the first step of the process, a film of cobalt-containing magnetic iron oxide is prepared by depositing cobalt to nucleus magnetic iron oxide powder such as gamma-Fe2O3. The surface of this film contains hydroxide of at least one of Cu, Al, Ti, Zr, Sn, V, Nb, Sb, Cr, Mo, W and Ni, formed by a suitable treatment. A vapor treatment is conducted after or before the treatment for forming the hydroxide. The cobalt-containing magnetic iron oxide thus formed exhibits, when it is formed into a magnetic coating agent, a good dispersion in an organic binder. A magnetic tape having superior rectangular ratio and excellent orientation characteristic can be obtained by using this magnetic iron oxide as the material. |
