With1941camePET.At the Calico Printer’s Association in Manchester, England, Rex Whitfield. And James Dickson furthered research that had previously been ended one by Wallace Carothers(Bellis). PET possesses excellent high‐temperature properties, high strength, and clarity, and has high oxygen and carbon dioxide barrier properties. Often used for medical application pouches, boil‐in‐bag applications, meals, snacks, and baked goods, PET is an important player in the field of flexible packaging.