Iron oxide magnetic powder and magnetic recording medium using the same
AssigneeSony Corporation
InventorsMakoto Inoue, Akiko Watanabe, Taro Sasaki
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Abstract
Iron oxide magnetic powder having small crystallite size and a small specific surface area, a manufacturing method therefor and a magnetic recording medium having excellent surface characteristics and satisfactory electromagnetic conversion characteristics are provided. The iron oxide magnetic powder contains crystallite having size of 30 nm or less when measured by an X-ray diffraction method and has a specific surface area of 30 m.sup.2 /g or less when measured by a BET method, and a magnetic recording medium using the iron oxide magnetic powder as the magnetic member thereof are provided.
Claims3
A magnetic recording medium comprising:
- a magnetic layer containing iron oxide magnetic powder including crystallite having size ranging from 17 to 28 nm when measured by X-ray diffraction using Co--K.alpha.1 ray from a half value width of a peak of a plane having a plane index of 311 and in accordance with a Sherrer's equation, and a specific surface area ranging from 26 to 28.8 m.sup.2 /g when measured by a BET method and a binder, wherein said magnetic layer is formed on a non-magnetic support member.
Dependencies are inferred from the claim text.