Protective Coatings for Automotive Transparent Plastic Glazing

For certain automotive glazing applications, replacement of glass with transparent coated thermoplastic polymers is under increasing consideration. This trend is fueled by the desire to reduce cost and weight and to increase occupant safety and design flexibility. Regulations currently permit use of “rigid” safety plastics as automobile glazing in areas not requisite for driver visibility, and a petition to expand use of these materials was recently submitted to the National Highway Traffic Safety Administration.

With proper surface protection, transparent coated plastics have successfully replaced glass in a wide variety of end use applications. Pertinent examples include ophthalmic lenses, safety eyewear and face shields, and glazing for aircraft and mass transit vehicles. Technological advances in transparent protective coatings for these materials have increased the potential for their successful use in automotive applications. Several recent automotive programs have further demonstrated that coated transparent plastics can provide excellent durability.

Key coating performance characteristics are necessary for surface-enhanced transparent plastics to meet the demands of the automotive service environment. These performance requirements will be discussed. In addition, test methods and properties of various coating compositions will be summarized. Certain limitations of coated transparent plastics compared to glass also will be presented. A coated transparent thermoplastic system that shows excellent promise for automotive glazing will be introduced.