| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a magnetic recording medium having excellent electromagnetic transducing characteristics and the running durability. SOLUTION: The magnetic recording medium includes a magnetic layer having a ferromagnetic hexagonal ferrite powder and a binder on a nonmagnetic supporting body, in which (1) the magnetic layer includes diamond particles having the mean particle diameter of 0.03-0.5μm with the proportion 0.1-5 mass% of the ferromagnetic hexagonal ferrite powder, (2) the mean plate diameter of the ferromagnetic hexagonal ferrite powder included in the magnetic layer is 5-40 nm, and (3) the binder included in the magnetic layer is at least either of (a) a binder including 0.2-0.7 meq/g of the polar group selected from -SO3 M, -OSO3 M, -PO(OM)2 , -OPO(OM)2 , and -COOM (where M designates hydrogen atom, alkaline metal, or ammonium) and (b) a binder including 0.5-5 meq/g of the polar group selected from -CONR1 R2 , -NR1 R2 , and -N<+> R1 R2 R3 (where R1 , R2 , and R3 represent hydrogen atom or alkyl base).</p> |
