| 摘要 |
Extruded thermoplastic film(5), 20-1000 microns thick is delivered to a polishing stack with three or four rolls, the first pair(1,2) of which forms a first polishing nip and further rolls(3,31) form a second polishing nip or a pressure nip. The ratio of the die gap width to film thickness is 1:1 - 1:6. Extruded thermoplastic film(5), 20-1000 microns thick is delivered to a polishing stack with three or four rolls, the first pair(1,2) of which forms a first polishing nip and further rolls(3,31) form a second polishing nip or a pressure nip. The ratio of the die gap width to film thickness is 1:1 - 1:6. The quotient of film speed in the second polishing gap or in the pressure gap divided by the film speed in the first polishing gap is 0.8-1.05. A third roll(3) may be positioned close enough to one of the rolls to create the second polishing nip. An Independent claim is included for a film produced by the process. |
