Toyota Automatic Loom Works Ltd exhibits a large window made of polycarbonate (PC) named "Panoramic Roof" at the 40th Tokyo Motor Show. It is a roof window that has an area of 1.54m2.
The company says "it is the top class among commercialized windows." While a glass window of the equivalent size is 20kg, the PC window is 11kg, which is roughly 50% in weight.
A silicon material was flow-coated on the surface to improve light resistance and durability against chipping. It has already reached the level of commercialization.
"It is more expensive compared with a glass roof, but can create high added value by integrating the roof with the installation area by casting, for example," the company said. "The windows will be supplied for reduction of vehicle weight, which is required to satisfy the strict emission control."
The company also exhibited a rear window. The roof window was injection-formed, while the rear window exhibited for reference was formed by bending. This method makes it possible to create various shapes responding to the design, but the issues such as resistance to scratches by wipers and heat resistance against the rear defogger remain unsolved.