CHEMICAL FILM
Chemfilm, sometimes called aluminum chromate, Alodine or Iridite, is a chemical conversion coating that is used to passivate aluminum. It protects aluminum substrates from corrosion and serves as a base for organic coatings while leaving dimensions unchanged. This process may be done in either a clear or a golden finish. The clear finish is near colorless and provides minimal electrical resistance; whereas, the golden finish is much thicker and is mainly used to increase corrosion protection as well as paint adhesion.