| 摘要 |
PROBLEM TO BE SOLVED: To provide ferromagnetic metallic powder excellent in dispersion property and application property by coating ferromagnetic metallic fine powder with a specified quantity of Ca, and besides, adjusting moisture to a specified quantity. SOLUTION: These are metallic magnetic powder which contains 1-5atom% Ca to iron and besides contains 0.5-2.0wt.% moisture, and a magnetic magnetic recording medium which has a magnetic layer using this metallic magnetic powder. Fro oxyiron hydroxide to become the material of the metallic magnetic powder, fine powder 0.05-0.3μm in longitudinal axis and 3-15 in axial ratio is used. Then, this oxyiron hydroxide is heat-treated at 400-620 deg.C in reductive atmosphere, and further is heat- treated at 400-750 deg.C in nonreductive atmosphere, whereupon the oxyiron hydroxide becomes an ion oxide, and the coating layer gets firmly fixed as an oxide layer. Next, deoxidizing processing is performed to the ferromagnetic metallic powder to form a film oxide, and then gas containing moisture is brought into contact with the ferromagnetic metallic fine powder so as to control the quantity of additional moisture on the surface; these are such manufacture of metallic magnetic powder and a magnetic storage medium using this.
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