| 摘要 |
PURPOSE:To obtain stable magnetic powder having excellent retentivity, a square ratio, and dispersing property, by adhering the compound of Mn and the like to the material wherein metal or oxide of Co and the like is doped to oxy iron hydroxide, then performing dry-reducing by reducing gas. CONSTITUTION:To oxy iron hydroxide such as alpha-FeOOH, beta-FeOOH, and the like, iron oxide such as alpha-Fe2O3, gamma-Fe2O3, and the like; or the material wherein one or more metals or the oxides thereof of Co, Mn, Ni, Zn, Cr, and Cu are doped to the above described material; are adhered and precipitated the two or more hydroxides of Co, Ni, Zn, Cr, Cu, and Mn. After said treatment, the treated material is dried, dry- reduced in the reducing gas stream such as hydrogen and the like at the temperature 200-600 deg.C, thereby alloy powder is obtained. In this method, is obtained the stable magnetic powder for recording: wherein deformation and the burning are prevented; the retentivity, the square ratio, and the dispersing property are excellent; and the ignitability is suppressed. |
