| 摘要 |
<p>A biaxially oriented oxygen and moisture barrier film and a method of producing such a film which comprises co-extruding at least one polyolefin polyolefin layer, at least one layer of an ethylene vinyl alcohol copolymer with a melt flow rate of at least about 8 grams per 10 minutes, and an adhesive layer wherein the layers are combined into a composite sheet with the adhesive interposed between the polyolefin layer and ethylene vinyl alcohol copolymer layers. Next, the composite sheet is immediately cooled so that the crystallinity of the ethylene vinyl alcohol copolymer is no more than about 25 percent. Finally, the composite sheet is biaxially oriented in the longitudinal direction to a degree of about 2:1 to about 4:1 and in the transverse direction to a degree of about 3:1 to about 7:1.</p> |
