The company Asahi Kasei began in the year 1931 with the production of chemicals that included ammonia and nitric acids. In 1949, exchanges between stocks started up between Tokyo, Osaka, and Nagoya. Asahi Kasei entered into a joint petrochemical venture with Dow Chemical. A production of Polystyrene and Saran Wrap began in 1952. Diversification into acrylonitrile, construction materials, petrochemicals, glass fabrics, ethylene, housing, medical devices, electronics, engineered resins, semiconductors, pharmaceuticals and liquors began in the 1960s and 1990s. Net sales exceeded $10 billion globally in the years 2000-2003. Finally in the years 2008-2009, there was further diversification into medical devices.