| 摘要 |
PURPOSE:To obtain hexagonal system ferrite magnetic powder having large saturated magnetic flux density by bringing magnetic powder to be eventually obtained into contact with 0.01wt.% or more of 1-20 organic nitrogen compound or organic nitrogen/oxygen compound respect to the magnetic powder. CONSTITUTION:Aqueous solution containing 8-16 to 0.8-3 of molar ratio of Fe ions to one or more metallic ions selected from a group consisting of Ba, Sr, Ca and Pb is mixed with aqueous alkaline solution, such as ammonia, ammonium carbonate, etc., and copresipitate is produced under the conditions of the liquid temperature of 25 deg.C and of pH5 or above. In this case, after the quantity of 0.01wt.% or more is brought into contact with magnetic powder for eventually obtaining 1-20 organic nitrogen compound such as alicylic amine like methyleamine, ethylamine, etc., or organic nitrogen/oxygen compound such as amino alcohol like monoethanolamine, diethanolamine, etc., it is heated to obtain hexagonal system ferrite magnetic powder. |
