Tubular, multi-layer film and method of making

Abstract From the Canadian patent

A multi-layer film and method for making the film by extrusion comprising a central barrier layer of a polymeric barrier material having edge portions which overlap along a weld line, inner and outer polymeric adhesive layers on opposite sides of the central barrier layer, which adhesive layers completely encapsulate the central barrier layer, and inner and outer polymeric surface layers in which the inner surface layer is adhered to the inner adhesive layer, and the outer layer is adhered to the outer adhesive layer the over-, lapping edge portions of the barrier layer provide a tubular film of uniform thickness and low oxygen transmission over the entire peripherial surface of the film …