Central Saint-Gobain: first light-regulating auto glass for Japan

Central Saint-Gobain Co., a joint venture between Japan“s Central Glass Co. and France“s Compagnie de Saint-Gobain SA, will market the first light-regulating auto glass in Japan. The company plans t…

Central Saint-Gobain Co., a joint venture between Japan“s Central Glass Co. and France“s Compagnie de Saint-Gobain SA, will market the first light-regulating auto glass in Japan. The company plans to start full-scale delivery by fiscal 2008. The product uses two sheets of glass whose inside surfaces are coated with a film containing tungsten oxide. When 1.5 volts of electricity is applied to the film, the tungsten oxide changes color, blocking light and heat. How much light and heat are allowed to pass can be controlled by the driver. The visible light transmittance of the glass is variable between 4-40% and solar radiation transmittance between 2-24%. It will be used in sunroofs, rear windows and rear side windows but not in the windshield or front side windows because it allows less than 70% of visible light through, below the domestic standard. The new glass is expected to be used first and foremost in luxury cars. The glass and control device will be sold as a set, with the price expected to be less than JPY 100,000.