Powder coating is a kind of solid powder synthetic resin coating composed of solid resin, pigments, fillers and additives. Different from ordinary solvent based coatings and water-based coatings, its dispersion medium is not solvent and water, but air. It has the characteristics of no solvent pollution, 100% film formation and low energy consumption. Powder coatings can be divided into thermoplastic and thermosetting coatings. Thermoplastic powder coatings have poor film appearance (gloss and leveling) and poor adhesion to metals, so they are rarely used in the field of automobile painting. Generally, thermosetting powder coatings are used for automobile painting. Thermosetting powder coatings take thermosetting synthetic resin as film forming material. during drying, the resin is first melted, and then cured into a flat and hard film after chemical crosslinking. The appearance, mechanical properties and corrosion resistance of the film formed by this coating can meet the requirements of automotive finishing.