| 摘要 |
PURPOSE:To provide excellent magnetic characteristics and prevent the inter- particle sintering by uniformly adhering a hydroxide or another compound of a metal to the fine particles of an oxy iron hydroxide or the like, then adhering a compound of silicon and a compound of aluminum, and thereafter reducing them. CONSTITUTION:When a metal compound is adhered to the surface of an oxy iron hydroxide or the like, ammonia, is uniformly and slowly generated in a water solution by a heat decomposition method of urea, so the number of the crystal nuclei of the metal compound is small, and the sediment of the metal compound is easy to grow on the surface of the oxy iron hydroxide or the like and can uniformly be adhered. In the ferromagnetic metal fine particles obtained by adhering the metal compound by means of this uniform adhesion, adhering the silicon compound and aluminum compound, and thereafter reducing them, the effect of the metal compound appears more remarkably in the ferromagnetic metal fine particles obtained by the reduction after the adhesion by the heat decomposition method of urea. With this, ferromagnetic metal fine particles are obtained which have good dispersion properties and also good effect of preventing the sintering. |
