| 摘要 |
PURPOSE:To produce iron oxyhydroxide having excellent acicular form, by reacting a ferric salt with an alkali metal hydroxide in the presence of a specific aliphatic polyhydric alcohol at a low temperature, and carrying out the hydrothermal treatment of the produced ferric hydroxide. CONSTITUTION:An aqueous solution of a ferric salt is made to react with an alkali metal hydroxide such as NaOH in the presence of an aliphatic polyhydric alcohol having >=2 hydroxyl groups, e.g. ethylene glycol, at <50 deg.C. The amount of the polyhydric alcohol is about 2-30mol per 1mol of the ferric salt. The slurry of ferric hydroxide produced by the reaction is subjected to the hydrothermal treatment at about 100-200 deg.C to obtain acicular iron oxyhydroxide. Since the produced iron oxyhydroxide particle has a particle length of about 0.2-0.6mum, an aspect ratio of about 10-25 and uniform shape, it is suitable as a material for the production of ferromagnetic powder. |
