Patent ID: 6254964
Filing Date: 2001-07-03
Classification: G11B,Y10T

Abstract:
A magnetic recording medium which comprises a support having thereon a substantially nonmagnetic lower layer and a magnetic layer comprising a ferromagnetic metal powder or a ferromagnetic hexagonal ferrite powder dispersed in a binder formed on the lower layer, which is a magnetic recording medium for recording signals having areal recording density of from 0.20 to 2 G bit/inch.sup.2, wherein the coercive force of said magnetic layer is 1,800 Oe or more, the average long axis length of said ferromagnetic metal powder is 0.15 .mu.m or less, the average particle size of said ferromagnetic hexagonal ferrite powder is 0.10 .mu.m or less; the dry thickness of said magnetic layer is from 0.05 to 0.30 .mu.m, .phi..sub.m is from 10.0.times.10.sup.-3 to 1.0.times.10.sup.-3 emu/cm.sup.2, and wherein said magnetic layer has a central plane average surface roughness of 5.0 nm or less measured by a 3D-MIRAU method.