| 摘要 |
PURPOSE:To realize high density recording by a method wherein complex oxide contains specified ranges (at%) of one or two kinds out of SrO and BaO, Cr203, and one or two kinds out of MgO, TiO2 and ZrO2, the residual part is constituent composition of iron oxide or the like, saturation magnetization is higher than or equal to a specified value, and Curie point is lower than or equal to a specified value. CONSTITUTION:The magnetic recording powder consists of complex oxide having hexagonal system ferrite type crystal structure wherein one or two kinds out of SrO and BaO of 14-20%, Cr203 of 20-40% and one or two kinds out of TiO2 and ZrO2 of 2-15% are contained, and the residual part has substantially constituent composition constituted of iron oxide and inevitable impurities. Thereby high saturation magnetization larger than or equal to 15emu/g is obtained, in the state that the Curie point (Tc) lower than or equal 155 deg.C and the coercive force of 8-10emu/g are ensured, so that high density recording is realized. |
