| 摘要 |
PURPOSE:To produce a magnetic iron oxide powder having high coercive force and low temperature coefficient of the magnetic properties, by adding a specific amount of Os atom to gamma-Fe2O3. CONSTITUTION:Magnetic iron oxide powder for magnetic recording medium is prepared by adding Os atom to gamma-Fe2O3. The atomic ratio of the Os atom to the Fe atom is 0.3-5.0%. The magnetic iron oxide powder has higher coercive force and lower temperature coefficient of the coercive force than Co-doped gamma-Fe2O3 or Co-coated gamma-Fe2O3 particles. A magnetic recording medium can be manufactured by applying the powder to a base by the aid of a binder, a dispersing agent and an organic solvent, etc., and drying to form a magnetic layer. |
