Heat shrinkable film structures with improved sealability and toughness

摘要

An irradiated multiple layer polymeric film comprising: (a) an outer protective layer comprising at least 50% to 99% EVA; and (b) an inner heat sealant layer comprising 0% to 50% of EVA and at least 50% to 100% of a material selected from the group consisting of ultra low density polyethylene, low density polyethylene, linear low density polyethylene, very low density polyethylene and ionomers; wherein the said heat sealant layer has a dose level of incipient cross-linking higher than the dose level of incipient cross-linking of said outer protective layer, said film being irradiated at a dose level between 1.5 and 10 megarads such that at a given radiation dose level said outer protective layer undergoes more cross-linking than said inner heat sealant layer.