| abstract |
(57) [Abstract] [Purpose] Needle-like α-oxy water that is effective for producing magnetic metal powders that are compatible with high density magnetic recording media without deteriorating magnetic properties and that are excellent in dispersibility. A method for producing iron oxide is provided. [Structure] A ferrous hydroxide slurry having an excess alkali concentration of 1.0 mol / l or more is oxidized with an oxygen-containing gas, and then an excess aqueous solution of aluminate is added, mixed and stirred, and then again containing oxygen. A needle-like α-oxyhydroxide characterized by being oxidized with gas to obtain a slurry containing free aluminate ions and α-iron oxyhydroxide, which is mixed and stirred, and then neutralized and aged, washed and dried. Iron manufacturing method. |