Effects of Moisture, Location, and Angle on Automotive Paint System Appearance During Natural Weathering

By Henry K. Hardcastle III

This article presents results from a simple Design of Experiment (DOE) in natural outdoor weathering. Results show comparative effects of three weathering variables: moisture, exposure angle, and exposure location. The experiment design reveals rank impor­tance of the study variables and links characteristics of the outdoor weathering environment with appearance degradation of coatings.

The DOE data follows gloss retention of four automotive paint sys­tems over 96 months in subtropical Florida and desert Arizona. The article discusses some of the root causes and co-variables which may explain automotive paint appearance degradation.