Cerium is a primary drier, promotes polymerization and imparts through drying properly. In alkyd based varnishes, Cerium is more active as compared to Lead. Cerium does not cause turbidity in oils and alkyd based varnishes as against lead. When used in combination with Cobalt and thereby offering an economy.
Cerium is used as lead free compositions and where sulphur containing pigments are used. It also resists atmospheric hydrogen.