摘要 |
In the plastic foil-producing apparatus where a fluent plastic mass is cooled in a roll nip between a roller member and a counter roller to a defined predetermined solidification temperature, the roller member includes a non-rotatable support member and a rotatable roller shell supported at the non-rotatable support member by one or more support elements. The roller shell includes a plurality of coaxial zones, namely, an inner soft rubber zone and a thin outer metallic zone possessing good thermal conductivity, for example, formed of copper or silver or alloys thereof, the outer surface of which is mirror smooth, for instance, chromium plated. The roller surface is cooled by cooling gas nozzles regulated by a temperature sensor, so that the temperature of the roller member in the roll nip assumes an exactly defined temperature. Consequently, there can be fabricated a plastic foil, for example, formed of polyethylene having a narrow solidification temperature range and possessing a defined thickness profile while preventing sticking of the plastic foil at the outer surface of the roller member.
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