| 摘要 |
PURPOSE:To obtain a magnetic recording body having improved electromagnetic transducing characteristics, durability, traveling performance, a reduced coefft. of friction especially at extremely low temp. and a significant antistatic effect by incorporating three kinds of carbon black of a specified average primary grain size into a magnetic layer formed on a nonmagnetic support. CONSTITUTION:This magnetic recording body consists of a nonmagnetic support and a magnetic layer formed on the support. The magnetic layer contains fine- grained carbon black of <=30mmu, preferably 10-25mmu average primary grain size, medium-grained carbon black of 50-100mmu, preferably 60-90mmu average primary grain size, and coarse-grained carbon black of >=200mmu, preferably 200-1,000mmu average primary grain size. Two or more kinds of fine-grained carbon black, medium-grained carbon black and coarse-grained carbon black may be used. The total amount of carbon black to be used is 1-20pts.wt., preferably 3-15pts.wt. per 100pts.wt. magnetic body. Less carbon black produces no antistatic effect, and more carbon black reduces the filling degree of the magnetic body in the magnetic layer and deteriorates the electromagnetic transducing characteristics. |
