Patent ID: 6964811

Claim:
A magnetic recording medium comprising a non-magnetic support, at least one undercoat layer containing an inorganic powder and a binder formed on said support, and a magnetic layer containing a magnetic powder and a binder formed on said at least one undercoat layer, wherein said magnetic layer has an average thickness of 0.3 μm or less, and said magnetic powder is a magnetic powder of substantially spherical or ellipsoidal particles comprising a core and an outer layer, said particles comprising a transition metal which comprises iron and a rare earth element which is mainly present in the outer layer of the magnetic powder particles, and having a particle size of 5 to 200 nm, a coercive force of 80 to 400 kA/m and a saturation magnetization of 10 to 25 μWb/g, wherein said magnetic powder particles are essentially free of boron, and wherein said magnetic powder has a uniaxial magnetic anisotropy one direction of which is a magnetization easy direction.