Pliofilm was a plastic wrap made by the Goodyear Tire and Rubber Company at plants in the US state of Ohio. Invented in the early 1930s, it was made by dissolving rubber in a benzene solvent and treating it with gaseous hydrochloric acid. Pliofilm was more stable in a range of humidities than earlier cellulose-based wraps and became popular as a food wrap. Its manufacture exposed workers to carcinogenic benzene and, when an additive was used to improve durability, caused dermatitis.