Sumitomo Chemical makes chemicals for almost everything made and grown under the sun. About one-third of the company's sales come from petrochemicals and plastics, such as polypropylene, ethylene, and elastomers. Sumitomo's other major units make pharmaceuticals, agricultural chemicals (insecticides, herbicides, and fertilizers), and basic chemicals, such as caustic soda and methanol. The firm also makes chemicals for electronics and fine chemicals. Part of Japan's Sumitomo Group, the company has 146 subsidiaries and 35 affiliates. Its pharmaceutical business operates through Sumitomo Dainippon Pharma. Sumitomo ranks among Japan's top three chemical producers, along with Mitsubishi Chemical and Asahi Kasei.