Alkali, Acid, Carbon Black and Oxide.They mainly include Caustic Soda, Caustic soda Flakes, Sodium Bisulfite, Sodium Hexametaphosphate, Sodium Tripolyphosphate,Copper Sulfate, Formic Acid, Glacial Acetic Acid,Oxalic Acid, Propionic Acid, all types of Carbon black, Iron Oxide, Magnesium Oxide, Zinc Oxide and so on