Corning ones and its manufacturing method of the iron alloy magnetic grain of magnetic recording and manufacturing method of the iron alloy magnetic grain for magnetic recording which uses said corning ones.

摘要

PURPOSE: To economically and industrially produce a granulated material for magnetic particles by adding a water-soluble semisynthesized starch or the like to a water suspension of acicular ferric hydroxide particles or acicular iron oxide particles, stirring, compacting, and dehydrating to obtain a cake and then granulating the cake. ;CONSTITUTION: Semisynthesized starch or semisynthesized cellulose which is soluble in water or warm water is added by 0.1-5.0wt.% and stirred in a water suspension of acicular ferric hydroxide particles or acicular iron oxide particles. The suspension is compacted and dehydrated to obtain a cake. This cake is granulated to obtain a granular material having 1-5mm average granule size, ≥0.5g/cm³ bulk density and ≤40% powdering rate for iron alloy magnetic particles for magnetic recording. This granulated material is heated and reduced in a reducing gas to obtain the objective iron alloy magnetic particles for magnetic recording. By this method, the obtd. alloy magnetic particles has high coercive force, large saturation magnetization and further shows a narrow distribution of coercive force and saturation magnetization among particles. Thus, the obtd. particles are suitable as magnetic particles for high-density recording.;COPYRIGHT: (C)1994,JPO&Japio