Nichtorientierte Polyesterfilme mit modifizierter heissversiegelbarer Schicht

摘要

A coextruded, heat sealable, nonoriented film comprising: (a) a nonoriented base layer comprising polyester and (b) a heat seal layer comprising about 50% to about 80% copolyester and about 20% to about 50% of an olefin polymer is disclosed. In one preferred embodiment the polyester base layer includes from about 1% to about 5% of a polyolefin, LLDPE being preferred; and in another preferred embodiment the polyester base layer comprises a resin which in a nonoriented film form has a tensile strength of 7,000 psi or more. The heat sealable film can be laminated with aluminum foil, paper, etc. to form a composite which is heat sealable, useful in pouches and lidding stock. The heat seal layer using about 30% to about 40% LLDPE as the olefin polymer is particularly useful when the film is laminated to aluminum foil and heat sealed as lidding stock to crystallized CPET trays.