Patent ID: 7157163

Claim:
A magnetic recording medium, comprising a lower non-magnetic layer containing at least a non-magnetic powder and a binder resin on one surface of a non-magnetic support, an upper magnetic layer containing at least a ferromagnetic powder and a binder resin on the lower non-magnetic layer, and a back coat layer on the other surface of the non-magnetic support, wherein the thickness of the upper magnetic layer is within a range from 0.03 to 0.30 μm, and the number of concavities with a depth of 30 nm or greater in the surface of the upper magnetic layer is 5 per 1 cm 2 of surface area or less, wherein the magnetic recording medium is formed by the process comprising: a step A of forming a lower non-magnetic layer by applying a non-magnetic layer coating containing at least a non-magnetic powder and a binder resin onto one surface of a non-magnetic support, and subsequently drying and curing the coating; a step B of forming an upper magnetic layer by applying a magnetic layer coating containing at least a ferromagnetic powder and a binder resin onto the lower non-magnetic layer, and subsequently drying the coating; a step C of forming a back coat layer by applying a back coat layer coating onto the other surface of the non-magnetic support, and subsequently drying the coating; a step D of performing calendaring following completion of both the step A and the step C; a step E of conducting heat curing following completion of the above steps; and a step F of performing additional calendering following completion of the heat curing of the step E.