| 摘要 |
PURPOSE:To suppress activity of hexagonal system ferrite as a basic irregular catalyst and to reduce mutual action as a solvent by surface treating the ferrite with boric acid or phosphoric acid. CONSTITUTION:Hexagonal system ferrite magnetic powder is surface treated with boric acid or aniline phosphate. The powder contains as main ingredient fine particles of hexagonal system ferrite represented by a general formula Mo.n(Fe2O3) (where, in the formula, M is at least one of Ba, Sr and Ca, and n=5-6). The aniline phosphate includes orthoboric acid ions, diborate ions, tetraborate ions, etc. The aniline phosphate includes orthophosphoric acid ions, pyrophosphoric acid ions, etc. Thus, activity as basic irregular catalyst is suppressed, and mutual action with solvent is reduced. |
