Patent ID: 6103340
Filing Date: 2000-08-15
Classification: G11B,Y10S,Y10T

Abstract:
A magnetic recording medium comprising a nonmagnetic substrate having provided thereon an intermediate layer consisting essentially of magnetic powder having a Mohs hardness of not less than 3 and an average particle size of not greater than 0.5 .mu.m and/or nonmagnetic powder having a Mohs hardness of not less than 3, carbon black, and a binder and, as a top layer, a magnetic layer consisting essentially of ferromagnetic metal powder and a binder, in whichsaid magnetic layer has an average center-line surface roughness (Ra) of not greater than 7 nm, andsaid magnetic layer has an average center-line surface roughness (Ra) of 10 to 30 nm after being immersed in a hydrochloric acid aqueous solution for 24 hours.