| 摘要 |
<p>PURPOSE:To enable high density recording and to increase reproduced output by consisting magnetic powder of a hexagonal crystal having uniaxial crystal magnetic anisotropy and specifying the ratio between grain size and thickness to a specific range and the tapping rate of the magnetic powder to a specific value. CONSTITUTION:The magnetic powder of a magnetic recording medium consisting of a supporting base and a layer of the magnetic powder coated on the surface of the base body consists of a hexagonal crystal having uniaxial crystal magnetic anisotropy. Said magnetic powder is so formed as to have 0.01-0.3mum grain size, 2.3-15 ratio between grain size and thickness and >=15% packing rate by tapping of the magnetic powder. The magnetic powder has hexagonal uniaxial crystal magnetic anisotropy. Substd. type hexagonal ferrite in which a part of Fe of hexagonal ferrite is substd. with at least one kind of metal selected from the group consisting of Co, Ti, Ni, Mn, Cu, Zn, In, Ga, Nb, Zr, V and Al is used. The magnetic powder having coercive force within a 200-2,000 Oe range is advantageous for high density recording.</p> |
