| 摘要 |
The invention relates to a method and to a device for producing a film made of at least two plastic foam layers (90, 91, 92). In order to form each plastic foam layer of the film, a thermoplastic synthetic material is initially melted in an extruder (1a, 1b) and is gassed with a chemical or physical foaming agent and, subsequently, the thus produced foaming melts are fed separately to a common coextrusion nozzle (6) wherefrom they are coextruded together in order to form the film. Each foaming melt passes through a cooling-down step (2a, 2b) after exiting the respective extruder and prior to entering into the coextrusion nozzle (6) wherein the foaming melts are cooled to a predetermined temperature independently from each other. |
