| 摘要 |
PURPOSE:To improve resistance to head and wear of the magnetic layer, by using the vinyl chloride-vinyl-propinate-vinyl alcohol copolymer, the low-molecular weight plasticizer, and the trifunctional low molecular weight isocyanate compound as binding components of magnetic powder. CONSTITUTION:3-50wt% trifunctional low-molecular weight isocyanate compound (C) is added to the mixture of 95-60wt% vinyl chloride-vinyl-propionate-vinyl alcohol copolymer (A) of 200-600 polimerization degree consisting of 70-80wt% vinyl chloride, 1-25wt% vinyl propionate, and 5-20wt% vinyl alcohol and 5-40wt% low-molecular weight plasticizer (B) of <=800 molecular weight such as dioctyl phthalate, thereby obtaining binder components. The magnetic coating material obtained by dispersing these binder components and magnetic powder in the organic solvent is applied onto the substance and is dried to form a magnetic layer. |
