420 Aluminium Powder
Aluminium powder is added to increase toughness and to shield the substrate from ultraviolet radiation. Adding between 5% to 10% of 420 Aluminium powder by volume will provide protection from ultraviolet light in areas which are not protected by other coatings. For this reason it is often used as a base for subsequent painting. The additive will also substantially increase the hardness of any coated surface.