| 摘要 |
PURPOSE:To eliminate a sticking phenomenon in a thermal transfer and to enable a high-speed recording and a sharp character and image printing, by using a biaxially oriented thermoplastic polyether ketone resin film having a specific F-5 value, thermal shrinkage factor, and film thickness for a substrate film. CONSTITUTION:A polyether ketone resin film is biaxially oriented and required to have the sum of a lengthwise F-5 value and a crosswise F-5 value of 22kg/mm<2> or more or, preferably, 24kg/mm<2> or more. If the sum of the F-5 values is less than 22kg/mm<2>, the running film may be folded or wrinkled. On the other hand, the polyether ketone resin film necessarily has a thermal shrinkage factor of 0.3% or less or, preferably 2.0% or less, at 150 deg.C and a thickness of 0.5-8.0mum or, preferably, 0.8-6.0mum. The use of a thick substrate film is not preferable because it causes an area heated by a thermal head to hardly coincide with an area of a coloring layer heated and melted by a heat conduction, thus generating bleeding, deteriorating the sharpness of recording, and lowering the resolving power. |
