发明名称 |
Magnetic recording medium and method for producing the same |
摘要 |
A magnetic tape having a polymer substrate and a magnetic layer which is formed directly on a surface of the substrate or on a primer layer formed on the substrate and contains cobalt, oxygen and optionally nickel, in which a coercive force is at least 120 kA/m and a squareness ratio is at least 0.9 in a hysteresis loop which is obtained when a magnetic field is applied in a plane of the magnetic layer in a longitudinal direction of the magnetic tape, and on the hysteresis loop, an intensity of the applied magnetic field, at which a magnetization when the applied magnetic field is increased is 99% of the magnetization when the applied magnetic field is decreased, is not larger than 400 kA/m, and preferably, a ratio of a value of magnetization at an intersection between a tangential line drawn at a point which gives a residual magnetization at the applied magnetic field of 0 (zero) and a tangential line drawn at a point which gives a coercive force with a magnetization of 0 in a second quadrant to said residual magnetization is at least 0.9, which magnetic tape has improved high density recording/reproducing properties.
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申请公布号 |
US5554440(A) |
申请公布日期 |
1996.09.10 |
申请号 |
US19930118326 |
申请日期 |
1993.09.09 |
申请人 |
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. |
发明人 |
ISHIDA, TATSUAKI;SUGITA, RYUJI;TOHMA, KIYOKAZU;BAN, YASUAKI |
分类号 |
G11B5/64;G11B5/65;G11B5/66;G11B5/73;G11B5/738;G11B5/85;H01F1/11;(IPC1-7):G11B5/66;G11B5/70 |
主分类号 |
G11B5/64 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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