Koppers is a global chemical an materials company based in Downtown Pittsburgh, Pennsylvania, United States in an art-deco 1920's skyscraper, the Koppers Tower. The corporation is divided into two divisions: Carbon and Chemicals, and Railroad and Utility. The company specialises in manufacturing carbon chemicals from coal tar. The five main chemicals that are produced are coal pitch for steel and aluminum production, carbon black for rubber vulcanization, creosote for wood treatment, and naphthalene and phthalic anhydride for plastics and polyester. Kopper's coal tar pitches are essential to manufacturing carbon anodes for aluminum smelting. Koppers also has extensive operations making creosote treated wood products, especially railroad ties and swtiches. Utility poles, foundations, decking materials, and wooden panneling are also produced by the company. Through its subisdy, Arch Wood Protection, the corporation also develops chemicals that protect wood from being weathered.