| 摘要 |
PURPOSE:To improve running properties and storage stability by forming a ferromagnetic metallic thin film over a nonmagnetic base, and prividing a film of polyurethane containing higher fatty acids and their derivatives over the opposite surface of the base to saide magnetic layer. CONSTITUTION:A polyester film is used as a base and over its surface, a Co- Ni ferromagnetic metallic thin film is formed by vacuum deposition. The opposite surface of this magnetic film to said magnetic layer side is coated with a paint obtained by dissolving a stearic acid, its metallic salt, its amide, etc., in a polyurethane solution and then adding and dispersing graphite uniformly. The polyurethane resin is compatible with higher fatty acids and their derivatives to tightly adhere the film, containing the dispersed graphite, to the film. The operation of this back film improves the running properties of the magnetic tape and reduces the frictional resistance by about 35%. Further, it has corrosion resistance, so the storage stability of the magnetic tape is also improved. |
