PRODUCTION OF PLATE BA FERRITE FINE PARTICLE POWDER FOR MAGNETIC RECORDING

摘要

PURPOSE:To produce plate Ba ferrite fine particle for magnetic recording use, by modifying the surface of a plate Ba ferrite particle with spinel iron oxide in the presence of a sulfate. CONSTITUTION:Plate BaFe12O19 fine particle is mixed with an alkaline suspension of Fe(OH)2 of 8-14pH containing 5-30%(atom) Fe<(>II<)> based on the whole Fe<(>II<)> in the plate BaFe12O19 fine particle. The mixed liquid is heat-treated at a temperature between 60 deg.C and the boiling point under atmospheric pressure, in the presence of a sulfate to convert the surface of the plate BaFe12O19 fine particle with a spinel iron oxide.