Novel self-cleaning coatings

Decorative and functional coatings with self-cleaning or easy-to-clean properties are presently in growing demand. These properties can be achieved according to the concepts of superhydrophobicity, superhydrophilicity or photocatalysis. The self-cleaning or easy-to-clean properties of such coatings are however significantly degraded, when the coated surfaces are exposed to chemical or mechanical loading, as by contact with surfactants or by scratching, which changes the surface tension and topography. The present attempt aimed at the generation of surfaces with self-cleaning properties, which are less prone to scratching or contact with surfactants. The underlying concept bases on the use of UV/IR-reflecting additives in coatings which cause the weakening or degradation of a dirt bonding. The self-cleaning properties of coatings are evaluated by outdoor exposure and a new laboratory short-time test. A further focus is also on the UV protection of coatings.