| 摘要 |
PURPOSE:To obtain a superior magnetic tape for high-density recording by improving sticking strength between a magnetic metallic thin film and a plastic film which has specific surface roughness, by forming the magnetic metallic thin film on the plastic film and by heating it under specific conditions. CONSTITUTION:On a film of polyethylene terephtalate, etc., meeting surface roughness requirements, Ra<=0.03mum and Rm<=0.3mum (Ra: mean surface roughness, Rm: maximum surface roughness), Al is vapor-deposited thinly as a base, and a magnetic metallic thin film of Co-Ni alloy, etc., is vapor-deposited. Under the conditions of heat treatment time (t) and heat treatment temperature T shown by expressions, the heat treatment is done while a running speed and contact section distance between a heat roller and the film are so adjusted that the surface temperature of the heat roller is T and the time of contact with the heat roller is (t). Thus, a durable magnetic tape for high-density recording is obtained which is free of a breakaway of the magnetic metallic layer from the film. |
