Biaxially oriented heat-shrinkable film
AssigneeViskase Corporation
InventorsPaul N. Georgelos, James E. Pelkie, Darrel L. Wilhoit
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Abstract
An improved biaxially oriented heat-shrinkable film of the type used for packaging food, such as poultry, processed meat, and fresh meat.
Claims16
A biaxially oriented heat-shrinkable film comprising a three component blend of very low density polyethylene (VLDPE), ethylene vinyl acetate (EVA) and ethylene alpha-olefin plastomer copolymer of density below about 0.90 g/cm.sup.3 and having a melting point between about 55.degree. C. and about 85.degree. C. as major components, wherein said VLDPE comprises between about 24 and about 38 wt. %, said EVA comprises between about 28 and about 40 wt. % with a vinyl acetate content of less than about 18 wt. %, and said plastomer comprises between about 33 and about 45 wt. % of said three component blend.
In a method for manufacturing a biaxially oriented heat-shrinkable film wherein a primary tube is extruded, cooled, reheated and stretched in the machine direction and inflated in the transverse direction by internal gas to form a bubble, then collapsed and withdrawn as biaxially oriented thinner film:
- the improvement comprising forming the primary tube from a three component blend of major constituents consisting of very low density polyethylene (VLDPE), ethylene vinyl acetate (EVA) and ethylene alpha-olefin plastomer copolymer of density below about 0.90 g/cm.sup.3 wherein the VLDPE comprises between about 24 and about 38 wt. %, said EVA comprises between about 28 and about 40 wt. %, and said plastomer comprises between about 33 and about 45 wt. % of said three component blend.
An irradiated biaxially oriented heat-shrinkable bag formed from film comprising a three component blend of very low density polyethylene (VLDPE), ethylene vinyl acetate (EVA) and ethylene alpha-olefin plastomer copolymer of density below about 0.90 g/cm.sup.3 as major components, wherein said VLDPE comprises between about 24 and about 38 wt. %, said EVA comprises between about 28 and about 40 wt. %, and said plastomer comprises between about 33 and about 45 wt. % of said three component blend.
Dependencies are inferred from the claim text.