| 摘要 |
PURPOSE:To obtain metal magnetic powder having relatively high hardness, excellent magnetic properties, electromagnetic conversion characteristic and dispersibility in a binder resin, to improve the durability, magnetic properties and electromagnetic conversion characteristic of a magnetic recording medium by incorporating mainly iron and specific amounts of manganese and alkaline earth metal therein. CONSTITUTION:Iron is mainly contained, 0.1wt.% or more of manganese with respect to iron are contained, and 1-50 times of amounts of alkaline earth metal with respect to the manganese are contained. Metal magnetic powder is manufactured, for example, by coprecipitating iron ions and manganese ions for synthesizing goethite which is the material of the powder mainly containing the iron thereby to produce the goethite in which the manganese is contained in solid solution, covering the goethite with alkaline earth metal compound or with manganese compound and alkaline earth metal compound, and reducing the goethite and alpha-Fe2O3 obtained by reducing the goethite in a hydrogen gas stream. |
