Calendering (Fig. 1) is widely used as a means of coating substrates and – depending on the machine configuration and material structure – can also be used as an alternative to extrusion coating.
Calenders are typically used with medium coating thicknesses. Low-melting grades of Desmopan® and Texin™ adapted specially for the technique can be processed on virtually all standard calender configurations. An extruder should be used to feed the TPU into the roller nip in the form of a preplasticated melt.
Fig. 1: Calendering Unit