Abstract: There is disclosed a magnetic recording medium comprising a non-magnetic substrate and a magnetic membrane composed of Co and oxygen formed thereon, which is characterized in that the saturated magnetic flux density of said magnetic layer is in the range of 8,400 G to 12,600 G, the oxygen content of said layer is in the range of 11 to 29 at %, and the residual magnetization in the in-plane direction of the membrane surface, Mr , and the residual magnetization in the perpendicular direction to the membrane surface Mr.perp., have a relation satisfying Mr /Mr.perp.>1 and the C-axis of Co of the magnetic membrane is oriented in a perpendicular direction to the membrane surface.

Abstract: A magnetic recording medium which comprises a non-magnetic substrate, a magnetic film formed on the substrate and a protective film provided on the magnetic film, the protective film being composed of at least two groups of element, the element in one group being at least one of B and C having a smaller atomic size, and a concentration of the element increasing from the interface side of the protective film with the magnetic film toward the opposite face side throughout the protective film has an improved durability against a magnetic head.

Abstract: A magnetic recording medium comprising a non-magnetic substrate, a soft magnetic layer formed thereon, and a perpendicularly magnetizable layer formed on the soft magnetic layer, where at least the soft magnetic layer is a vapor deposited mixture layer composed of an organic material and a ferromagnetic material, has distinguished flexibility and durability.

Abstract: A magnetic recording medium comprising a substrate, an underlayer provided on the substrate and having a high permeability magnetic film and a relative permeability in all directions in the film surface of not less than 800, and a recording medium layer provided on the underlayer and having a perpendicular anisotropy. The recording and reproduction characteristics of this magnetic recording medium do not vary even when the direction of movement thereof with respect to a magnetic head varies. When it is applied to a magnetic disc, preferable results can be obtained.