A method for making a vacuum packaging film includes flowing a plastic melt, from a multi-layer extruder, onto a rotating roller. The plastic melt is then cooled while simultaneously imparting a pattern, via a pattern imparting means, onto the plastic melt resulting in the vacuum packaging film. ...http://www.google.es/patents/US20040256050?utm_source=gb-gplus-sharePatente US20040256050 - Forming evacuation channels during single and multi-layer extrusion process
Forming evacuation channels during single and multi-layer extrusion process
Número de solicitud: 10/801,950 Número de publicación: US 2004/0256050 A1 Fecha de presentación: 15 Mar 2004 Patente emitida: US7517484 ( Fecha de emisión 14 Abr 2009)
