US Patent 7201966 Packaging films containing coextruded polyester and nylon layers

Multilayer coextruded thermoformable structures for packaging film applications. The multilayer structures having at least a first layer comprising polyethylene terephthalate, a second layer of a first adhesive comprising a blend of at least an acrylate-based resin and either a modified polyolefin or a modified acrylate-based resin; a third layer of a thermoplastic oxygen barrier. The thermoplastic oxygen barrier may comprise ethylene/vinyl alcohol copolymer (EVOH), polyvinylidene chloride, or polyamide, preferably, a polyamide blend containing between 1–29% amorphous polyamide. The present invention may further comprise at least 5–7 thermoplastic layers.