METHODS FOR THE EVALUATION OF THE DEGRADATION OF COLORED COATING PRODUCTS SUBJECTED TO OUTDOOR ENVIRONMENTAL ACTIONS

External environment can act on colored coating products used as construction finishing materials through climatic factors (UV radiation, moisture, temperature) causing photochemical degradation reactions at the structural level, with direct implications on the aesthetic character through loss of the colorimetric properties but also on the protective role by reducing physical and mechanical properties. From this perspective, accelerated test exposure to UV radiation under conditions that simulate the action of climatic factors from natural environment are of particular importance, and evaluating methods for colored coating products degradation at the end of exposure offers the possibility to obtain the data about their behavior in service. This article presents methods of visual evaluation on colored coating products degradation, which are based exclusively on qualitative evaluations influenced by the examiner, compared to the instrumental methods that allow to reduce the uncertainty induced by the human factor, and to obtain accurate and quantifiable results to contribute in establishing the sustainability and the performances of the finishing coating materials.