| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic recording medium excellent in dispersibility, coating film smoothness, electromagnetic transducing performance, and running durability. SOLUTION: The magnetic recording medium has at least a magnetic layer made by dispersing ferromagnetic powder in a binder on a non-magnetic base. The binder contains a polyurethane resin consisting at least of polycarbonate diol and organic diisocyanate, and this polyurethane resin has a glass transition temperature of 70-200°C. The ferromagnetic powder consists of ferromagnetic needles 20-50 nm long in major axis, flat magnetic plates 10-50 nm in diameter, or spherical or spheroidal magnetic substances 10-50 nm in diameter. Further, this magnetic recording medium may have a non-magnetic layer made by dispersing non-magnetic powder in the binder containing the polyurethane resin between the non-magnetic base and the magnetic layer. COPYRIGHT: (C)2009,JPO&INPIT
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