Process for the production of a ferromagnetic metal powder
AssigneeFuji Photo Film Co., Ltd.
InventorsEiichi Tadokoro, Masashi Aonuma, Yasuo Tamai
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Abstract
A ferromagnetic metal powder obtained by a reducing reaction of wet process or dry process is brought into contact with a solution containing phosphate ion. The ferromagnetic metal powder treated in this way is favorably used for magnetic recording media, in particular, suitable for high density recording.
Claims9
In a process for the production of a ferromagnetic metal powder containing at least 75% by weight of at least one metal selected from the group consisting of Fe, Co, Ni, Fe--Co, Fe--Ni, Co--Ni and Fe--Co--Ni by reducing a metal salt capable of forming the ferromagnetic metal powder with a reducing agent by a wet or dry process in the presence of a non-magnetic element or an organic compound, thus obtaining an oxidation resistant ferromagnetic metal powder, the improvement which comprises treating further the ferromagnetic metal powder separated from the reducing reaction system with a solution containing phosphate ions with a concentration of 0.00001 to 10 mols/liter at a temperature of from -10.degree. to +120.degree. C.
Dependencies are inferred from the claim text.