Three spools of polyethylene terephthalate filaments, 1943-1944.

UNITED KINGDOM - FEBRUARY 11: These are the earliest satisfactory samples of Terylene filaments, produced at the Chemical Research Laboratory in Teddington, Middlesex. Terylene is the trade name for polyethylene terephthalate, a polyester made from ethylene and terephthalic acid. Terylene was first produced by J R Whinfield and J T Dickson in the laboratory of the Calico Printers' Association Ltd, and patented on 29th July 1941. ICI bought the world manufacturing rights in 1947 and full-scale commercial production of Terylene began in January 1955. The material was found to be stronger than cotton, with better resistance to moisture, and therefore became a popular fibre for use in manufacturing shirts. Today it is a popular material for sportswear and high-tech fabrics. (Photo by SSPL/Getty Images)