Colored Systems with Improved Weatherfastness

Abstract

Weatherfastness of pigmented organic coatings is a classical problem in the industrial world. We describe the photoreactivity of some heterocyclic pigments from the 1,4-dioxopyrrolo[3,4-c]pyrrole (DPP) family in suspension and in a polymer matrix, and the discovery of the photostabilization of organic crystals by nitroxy radicals.