| 摘要 |
PURPOSE:To prepare a film which is suitable for a magnetic recording medium and has an excellent surface flatness and good handleability by roughening at least one surface of the film by fine inert particles in such a manner that specific conditions are satisfied. CONSTITUTION:The title film has at least one surface roughened by projections caused by fine inert particles and the surface has characteristics which, when measured with an optical, non-contact three-dimensional roughness tester, satisfy the following conditions simultaneously: (1) 0.01<=SRZ<=0.4 [wherein SRZ is a mean roughness of 10 points (mum)], (2) H0.1<=500 [wherein H0.1 is the number of projections (number/mm<2>) equal to or higher than 0.1mum], and (3) H0.01-0.05>=20000 [wherein H0.01-0.05 is the number of projections (number/mm<2>) with a height of 0.01-0.05mum]. |
