The evolution of surface texture in automotive coatings

摘要

The curing behavior and texture development of automotive clearcoats was studied by noncontacting profilometry and dynamic viscosity measurements during solvent evaporation and thermal curing. The changing surface texture was shown to be a strong function of temperature and solvent content. Leveling occurred during the initial heating of the clearcoats, while smaller wavelength roughness was observed to appear during cooling after curing. The dynamic viscosity was shown to be a strong function of catalyst loading. Numerical simulations were conducted to calculate the apparent viscosity during the leveling process. Calculated viscosity profiles matched theoretical predictions for the behavior of these clearcoats.