| 摘要 |
PURPOSE:To improve resistance to oxidation and conformity for magnetic recording medium by dissolving organic acid metallic salt on the particle surface of metal magnetic powder and making the particle surface bear that dissolved residue. CONSTITUTION:Metal magnetic powder, etc., of iron or iron alloys which contain iron as main component manufactured by various kinds of methods are used for metal magnetic powder (substrate constituting particles) to be used as a substance to be treated. And as copper salt of organic acid, one whose organic acid is of aliphatic hydrocarbon, one or aromatic hydrocarbon, one of alicyclic hydrocarbon, or the like is used. And the dissolved residue of copper salt of this organic acid is so treated as to be born on the surface of the substrate constituting particle. At that time, the substrate constituting particle powder is brought into contact with the liquid phase or gas phase and heated above the dissolution temperature of the copper salt of the organic acid so as to dissolve, or applied with replacement plating with the substrate constituting particle in the liquid phase line which contains copper salt of organic acid nobler than the substrate constituting particle so as to dissolve and bear. Hereby, resistance to oxidation is remarkably improved, and excellent magnetic characteristics can be held for a long period. |
