Perception and protection properties of paints with different color pigments

In several applications, a paint system needs to guarantee corrosion protection and abrasion properties together with good aesthetical appearance and perception. Clearly, the last aspects are of fundamental importance in the fields of architecture and product design. Today these aspects are required also for products for which, until some years ago, only technical properties were considered. Gloss and color of the surface are the most important characteristics to modify the perception of an object. The use of pigments, organic and inorganic, allows the production of a practically infinite palette of colors and effects. Particular pigments allow to obtain a sort of “smart surface” with an aspect changing with optical direction of sight or temperature. Other pigments show luminescent properties. Obviously, the paint must maintain the same visual aspect for all its service life. Solar exposure, UV radiation and corrosion damages could modify these properties. The change of surface aspect could also be the first signal of degradation, which could lead to a reduction of protection properties. The behavior of paint systems with different type and quantity of pigments is evaluated through laboratory UV exposure tests and natural weathering. Electrochemical tests together with gloss and color change measurements permit to evaluate the paint properties during the service life.