A new federal ruling has helped clear the way for polycarbonate to replace glass in more auto windows, opening the potential for plastic to be used everywhere but the front windshield.
The Department of Transportation's National Highway Traffic Safety Administration has said specially coated PC can be used for side and rear windows in place of glass. Plastics still must pass performance requirements of the federal government and carmakers, but it no longer has the same limitations.
``The interest is there, and what that provides is clarity as to whether [automakers] can plan on using polycarbonate,'' said Clemens Kaiser, chief executive officer of Exatec LLC, a Wixom, Mich.-based joint venture of GE Plastics and Bayer MaterialScience LLC that produces coatings for PC. Kaiser spoke in an Oct. 7 telephone interview.
PC has been limited to windows in nonpassenger areas of vehicles in the past, such as the back portion of a sports utility vehicle.
``It's a very positive step,'' said Anne Rohinsky, marketing communications manager for GE Plastics Automotive.
Coated plastics offer weight savings over glass as well as the potential to integrate other components and expand design ideas. Windows could swoop around corners or make rear tailgates lighter and easier to operate.
``There is a clear interest,'' said Folke Markus, marketing solutions manager for GE Plastics. ``With less weight, it can improve fuel consumption and there is more design flexibility with shapes not possible in glass.''
The plastics industry still must win over automakers and designers. The first large-scale PC window glazing manufacturing using Exatec's system is under construction by Botzingen, Germany-based auto supplier Peguform GmbH in the Czech Republic. The product will be sold under the trade name CleverGlass.