Although stockings have been around for centuries - and were usually worn by men - the invention of a new synthetic material in 1935, patented by the chemical company DuPont two years later, changed the game for hosiery. According to lore, in-house scientists at DuPont had been calling the material Duparon, which stood for DuPont pulls a rabbit out of nitrogen. The company planned to market the product as nuron - which is no run backwards - but due to trademarking issues settled on nylon. DuPont made a conscious decision not to trademark the name in the hope that it would come to be seen as synonymous with stockings. When the first test sale took place at the company's Wilmington, Delaware, headquarters on 24 October 1939 -- 75 years ago today -- 4,000 pairs sold out within three hours.