Thermoplastic film incorporating high melt index resins
AssigneeViskase Corporation
InventorsPaul N. Georgelos, Stanley Lustig
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Abstract
A biaxially stretched, heat sealable, thermoplastic, flexible, food packaging film, preferably multilayer, having an outer heat sealable layer comprising an ethylene vinyl ester copolymer, preferably a blend of two different EVA copolymers wherein said heat sealing layer (which is preferably crosslinked by irradiation) has an M.sub.w of 50,000 or more, and an M.sub.n between 1000 and 18,000.
Claims22
A biaxially stretched, heat sealable, thermoplastic flexible film comprising at least one outer heat sealable layer comprising a blend of (a) first copolymer of ethylene and a vinyl ester wherein said first copolymer has a melt index between about 0.2 and 0.7 dg/min as measured by ASTM D-1238, condition E, and (b) a second different copolymer of ethylene and a vinyl ester wherein said second copolymer has a melt index between about 2 and 10 dg/min as measured by ASTM D-1238, condition E, and wherein said blend containing layer has a weight average molecular weight (M.sub.w) of 50,000 or greater, and number average molecular weight (M.sub.n) between about 1,000 to 18,000.
A biaxially stretched film comprising:
- a heat sealing layer comprising a blend of a first copolymer of ethylene and vinyl acetate having a vinyl acetate content between 4 and 18 weight percent of the total first copolymer weight and a melt index between about 0.1 and 0.7 dg/min. as measured by ASTM D-1238, Condition E;
- and a second copolymer of ethylene and vinyl acetate having a vinyl acetate content between about 4 and 18 weight percent of the total second copolymer weight and a melt index between about 2 and 10 dg/min. as measured by ASTM D-1238, Condition E.
Dependencies are inferred from the claim text.