Micro cracks make the stretched polypropylene film lighter

The current physical voiding process can reduce the density of the BOPP (biaxially oriented polypropylene) film to 0.5 to 0.6 g/cm3. A newly developed BOPP film produced by the Triaxcell process can have a film density of 0.3 g/cm3 or even 0.2 g/cm3. This process was developed by Conenor Inc. (a technology development company) in Tampere, Finland, and its main purpose is to make frozen food packaging and adhesive labels.

This technique lowers the mold temperature to the crystallization temperature of PP, causes it to generate microcracks in the molten curtain state, and then performs longitudinal stretching to extend the crack. A transverse stretcher (developed by Conenor Corporation) was used to transversely stretch the mesh film. Finally, the mesh film passes through the tempering roll and is trimmed before winding. For the development of the product, Conenor has a pilot production line and is looking for a partner in the field of machinery for the development of production-scale production lines.

Source: Modern Plastics Processing Applications