Calendering

Calendering is a speciality process for producing high-volume, high quality plastic film and sheet, mainly used for PVC as well as for certain other modified thermoplastics (plastomers) available from Ultrapolymers. The polymer is subject to heat and pressure in a screw extruder. The molten polymer mass exiting the extruder is passed between rotating heated calendering rolls set at a specified gap from each other to form a sheet or film which is then cooled. The temperature and speed of the rolls influences the properties of the film. Calendering allows speciality surface treatments of the film or sheet such as embossing or enhancing the physical properties or in-line lamination to other substrates.