Magnetic recording medium comprising an underlayer containing alpha -iron oxide powder and a magnetic layer containing ferromagnetic metallic powder

摘要

Disclosed is a magnetic recording medium which comprises a non-magnetic support and a layer containing alpha -iron oxide powder as a lower layer and a layer containing ferromagnetic powder as an upper layer which are provided on the non-magnetic support in this order from a side of the non-magnetic support, wherein weight ratios of elements in the whole composition of the alpha -iron oxide powder are 0.05 to 5 parts by weight of aluminum (Al) atom and 0.05 to 5 parts by weight of silicon (Si) atom based on 100 parts by weight of iron (Fe) atom, and average existence ratios of elements in terms of the number of atoms forming the surface of the alpha -iron oxide powder are 40 or less of Al atom and 1 to 60 of Si atom based on the number of Fe atom as 100.