Use of analytical techniques to reveal the influence of chemical structure of clearcoat on its biological degradation caused by bird-droppings

The results revealed that a digestive enzyme (lipase) present in bird-droppings, can induce the hydrolysis reaction of coating polymer leading to a locally distributed etched surface. It was also found that the clearcoat containing higher ratios of melamine cross-linker had poorer performance against bird-droppings in spite of having a greater cross-linking density.