Producing extrusion products particularly economically through the combination of a variety of process steps - this is direct extrusion. In the production, for example, of panels of wood flour/PP, acoustic and insulation films/panels/pipes using BaSO4 or even in the production of thermoforming films and biaxially oriented films, the intermediate step of pellet production is foregone as a result. At the end of the compounding process, shaping follows, during which the extrudate is processed into semi-finished products.
In recent years, Leistritz has equipped a great many systems for the production of thermoforming films with twin screw extruders. The reason for this is that increasing numbers of film producers in this field rely on the special vacuum technology which makes it possible to process bottle flakes directly without predrying. Up to 100% recycled material can thus be processed without adding any new material. Since most thermoforming films are used for food packaging, the films are furnished with cover layers by means of co-extrusion during the production process.