| 摘要 |
PURPOSE:To improve the performance of tape running and the wear resistance of a head and to reduce the blinding of the head by providing a magnetic layer on the surface of a nonmagnetic base, a back layer on the rear face and applying heat treatment to the back layer including carbon black and silicone oil. CONSTITUTION:Any of liquid, consistency liquid and waxy solid silicone oil can be used. The silicone oil being liquid having a melting point of, preferably, <=40 deg., more preferably <=20 deg.C, and most preferably at room temperature and having a viscosity of 10,000cm-stokes at 25 deg.C attains better effect. It is effective to apply heat treatment at a process after calender processing, and it is applied to a roll after the calender processing, a tape cut off into a required tape width or a tape contained in cassette halves. The temperature is preferably 40-100 deg.C and most preferably 50-80 deg.C. The time is nearly 5-100hr. The humidity is not especially limited; acceptable for 10-90% RH. The smaller the grain size of the carbon black becomes, the larger the holding force of the silicone oil becomes, which is preferred. |
