| 摘要 |
PURPOSE:To obtain a stable magnetic storage body which has good running properties by forming a ferromagnetic thin metallic film over a nonmagnetic base, and forming a coating film of polyvinyl butyral containing an oil lubricant, etc., on the opposite surface of the base to said ferromagnetic layer. CONSTITUTION:On the surface of a polyester film as a nonmagnetic base, a ferromagnetic thin metallic film consisting of 80% Co and 20% Ni is formed by vaccum deposition. On the opposite surface of this magnetic film to said ferromagnetic film, a paint obtained by dispersing an oil lubricant such as a higher fatty acid deivative in a polyvinyl butyral solution by using a ball mill is applied. The polyvinyl butyral is compatible with higher fatty acids, higher fatty ester, higher fatty amide, etc., and carbon black, etc., is dispersed to form a strong film, obtaining high adhesive strength with the film. Thus, the running properties of a feromagnetic tape are improved. Further, this protective film serves to protect the watertightness of the magnetic layer and the also provides stability to repetitive use. |
