| 摘要 |
PURPOSE:To obtain the titled medium having excellent resistance to corrosion and wear by providing the magnetic recording layer of a ferromagnetic thin film on a nonmagnetic substrate and further furnishing a layer of the oxide film of an alloy of at least one kind of element among V, Nb and Ta and Co on the surface of the recording layer. CONSTITUTION:A nonmagnetic substrate 1 is formed with a plastic film such as polyethylene terephthalate, Al, glass, etc., having 5-100mum thickness. A magnetic recording layer 2 is formed by the vacuum deposition of a metal such as Fe, Co and Ni or the alloy contg. the elements and the thickness is regulated to 0.05-1.0mum. A protective layer 3 consists of at least one kind of metal selected from V, Nb and Ta or the oxide of the alloy of the elements and Co and the thickness is adjusted to 50-500Angstrom . At <50Angstrom , the effect as the protective and lubricating film is not exhibited and the clearance between a head and the magnetic recording layer 2 is increased and the recording and reproduction efficiency is decreased at >500Angstrom . The composition ratio of Co to V, Nb and Ta is preferably regulated to 1/9-9/1. When Co is rich, the corrosion resistance is not sufficiently improved and the effect in reducing the friction coefficient is small, when the content of Co is too small. |
