| 摘要 |
PURPOSE:To improve modulating noise at the recording and reproducing by providing the magnetic layer comprising dispersing ferromagnetic alloy powder in a binder, on a non-magnetic flexible film-form substrate of the specified surface roughness. CONSTITUTION:The magnetic layer 2 of thicknesses 2 to 8 mum which comprises dispersing about 75 to 90 wt% of ferromagnetic alloy powder in a binder and which has residual magnetic flux densities of about 2500 to 4000 gauss in the tape running direction is provided on the surface 3 of the non-magnetic flexible film-form substrate 1 whose thickness is about 4 to 32 mum, whose surface roughness at above length 10 mm in the tape running direction has the maximum value at frequency components below 100 Hz when spectrum-analyzed by the formula (f is frequency Hz; v is the relative moving speed of magnetic head and tape mm/sec.; lambda is the wavelength of the direction where the tape moves relatively mm) and which is 0.1 mu or under in the maximum value of its surface roughness at frequency components of 20 to 100 Hz. The roughness of the surface 4 of the layer 2 is preferably 0.1 mum or under. |
