Patent ID: 7166375

Claim:
A magnetic recording medium comprising, in sequence, on a nonmagnetic substrate: at least one soft magnetic underlayer; an orientation control layer a nonmagnetic intermediate layer; and a perpendicular magnetic layer having an axis of easy magnetization which is oriented mainly perpendicularly to the nonmagnetic substrate, wherein said orientation control layer is provided to control the orientation of the perpendicular magnetic layer, said nonmagnetic intermediate layer is provided between the orientation control layer and the perpendicular magnetic layer to improve the orientability and the coercive force of the perpendicular magnetic layer, and said nonmagnetic intermediate layer comprises a nonmagnetic alloy of cobalt, said soft magnetic underlayer has a multilayer structure consisting of a plurality of soft magnetic layers comprising a soft magnetic material, and one or more separation layers interposed between said soft magnetic layers, a direction of magnetization of an upper soft magnetic layer is different from a direction of magnetization of a lower soft magnetic layer, and the direction of the magnetization of said soft magnetic layer is along the radius of said nonmagnetic substrate and is oriented towards the periphery of the substrate or towards the center of said nonmagnetic substrate.