| 摘要 |
PURPOSE:To obtain magnetic iron powder for magnetic recording having excellent dispersibility by blowing gas contg. O2 to a liquid suspension prepd. by immersing reduced iron into dioxane thereby oxidizing the surface of the reduced iron. CONSTITUTION:The reduced iron obtd. by reducing metallic compd. powder contg. iron oxyhydroxide or iron oxide as the essential component is suspended into the dioxane. While said liquid suspension is kept stirred to the extent of properly mixing the same preferably by a propeller stirrer or the like, the gas contg. O2 as an oxidizing gas is blown thereto to oxidize the surface of the reduced iron and to obtain the desired magnetic iron powder. The dioxane may be any of 1,4- and 1,3-dioxane. The oxygen concn. of the above-mentioned oxidizing gas is about 0.1-25vol%. The reaction temp. is particularly preferably about 20-60 deg.C. The dioxane is removed from the magnetic iron powder by filtration or evaporation after the end of the oxidation reaction and thereafter, the powder is finished to the product.
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