Driers are materials that promote or accelerate the activity of hardening of film formers that contain reactive or oil elements. Air drying is the formation of a solid film at ambient temperature by oxidization processes from an applied liquid coating. Such coatings are convertible coatings in that the film, once drying, doesn’t re-dissolve within the original carrier solvent. The air-drying process may be represented as autoxidation because it takes place automatically when the coating has been unfolded. Autoxidation is a chemical process that’s greatly affected by temperature and also the presence of catalysts. Humidity also affects the autoxidation of typical paints and therefore the presence of light is helpful. We use cobalt for driers because it gives the best quality.