M. Pazani - Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Iran
S.A. Mostafavi Mousavi - Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Iran
M. Mohseni - Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Iran
B. Ramezanzadeh - Department of Surface Coatings and Corrosion, Institute for Color Science and Technology, Tehran, P.O.Box 654-16764, Iran

The objective of this study is to investigate the effects of black and silver basecoat pigmentation on the biological resistance of an automotive acrylic-melamine clearcoat. Simulated tree gum and bird droppings were exposed to the clearcoat surface. A post-aging testing approach was utilized to investigate the biological resistance of the samples. To this end, different techniques including digital camera, gonio-spectroscopy, optical microscope and a gloss meter were utilized to investigate the effect of biological materials on the clearcoat surface properties and appearance. It was found that basecoat pigmentation had great effect on the biological resistance of the clearcoat. The sample with silver basecoat pigmentation showed better biological resistance than black one due to the presence of aluminum flakes.

utomotive clearcoat- Biological resistance - Basecoat pigmentation - Goniospectroscopy- optical microscope