Patent ID: 6020022
Filing Date: 2000-02-01
Classification: G11B,Y10S,Y10T

Abstract:
A method for producing a magnetic recording medium having a lower non-magnetic layer and an upper magnetic layer, comprising:preparing a coating solution for the lower non-magnetic layer by combining a non-magnetic powder and a binder by selecting and combining the ingredients to yield a coating solution for the lower non-magnetic layer having a thixotropic property and containing either (a) an acicular inorganic powder having a Mohs hardness of 3 or more and a major axis length of 0.3 .mu.m or less or (b) a spherical inorganic powder other than carbon black having an average primary particle size of 0.08 .mu.m or less; preparing a coating solution for the upper magnetic layer by combining a ferromagnetic powder and a binder; coating the coating solution for the lower non-magnetic layer over a support; applying the coating solution for the upper magnetic layer over the lower non-magnetic layer while the lower non-magnetic layer is in a wet or dry state, to form an upper magnetic layer having an average dry thickness (d) of 1 .mu.m or less.