Plastic film transfer between a calender roll and other process rolls uses a transfer belt pressed against film at a specific temperature on the final roll

摘要

The moving film strip(20) is transferred from a roll(8) onto a motor-driven transfer belt(16) by pressing the belt onto the film at a point where it is still in contact with the roll. Tensile stress is exerted on the belt by the driving action and the belt is neither plastic nor elastic at this tensile stress and temperature. The moving film strip(20) is transferred from a roll(8) onto a motor-driven transfer belt(16) by pressing the belt onto the film at a point where it is still in contact with the roll. The film temperature on both the roll and on the transfer belt in the contact area is such that the film would plastically deform under the transporting forces if there were no belt present. Tensile stress is exerted on the belt by the driving action and the belt is neither plastic nor elastic at this tensile stress and temperature. The film strip(20) is extruded and passed through a calender(2) whose last roll forms the roll prior to the transfer belt. The roll has a higher surface temperature than the preceding rolls(4,6) over which the film passes.