Chemicals and pharmaceuticals giant Bayer on Thursday opened a major new factory in Dormagen, a suburb of Cologne, where it will produce polyurethane. The factory is the largest single investment the Leverkusen-based multinational company has made in Germany this year. The facility will produce 200,000 tons a year and will help facilitate growth in the company’s artificial materials business, CEO Werner Wenning said. Polyurethane, a raw material, is used in the production of foam rubber. The company has invested close to €200 million in the factory, including 20 percent for environmental protection measures.