A proprietary tear-resistant PET film developed by Webasto (Rochester Hills, MI) and Madico (Woburn, MA) enables a fully retractable panoramic roof system to meet all strength and performance requirement with thinner high strength fully tempered glass. A proprietary extrusion process and a unique laminating process for the 0.24-mm-gage film, which is carried out in an autoclave to eliminate bubbles, are employed in the manufacture of the assembly. Webasto has also developed a similar film together with Saint Gobin Performance Plastic (Livonia, MI).
The roof, installed in the Ford Lincoln MKZ, also incorporates unique plastic fasteners and retainers in place of steel clips for cost and weight reduction, as well as hard-coated polycarbonate trim panels in place of acrylic for improved scratch/mar performance and dimensional stability.
The PET film enabled use of fully tempered glass which meets FMVSS 205 requirements. Tempered glass is lower in cost than non-tempered and also tougher.