The thermosetting powder coating uses thermosetting resin as the film-forming material, and adds a crosslinking curing agent to form an insoluble and non fusible hard coating after heating. Due to the resin used in thermosetting powder coatings being a low degree of polymerization prepolymer with a low molecular weight, the coating has good leveling and decorative properties. Moreover, the low molecular weight prepolymer can form a network of cross-linked macromolecules after curing, resulting in good anti-corrosion and mechanical properties of the coating. Thermosetting powder coatings can be divided into the following types:

1. Thermosetting polyester powder coating

Thermosetting polyester powder coatings exhibit better weather resistance and UV rotation resistance than epoxy resins. In addition, due to the polar groups in polyester resin, the powder loading rate is higher than that of epoxy resin. During the baking process, it is not prone to yellowing, has high glossiness, good leveling performance, full paint film, light color, and other characteristics, thus having good decorative properties. Generally used in fields such as refrigerators, washing machines, vacuum cleaners, instrument casings, bicycles, furniture, etc.

2. Thermosetting epoxy powder coating

Thermosetting epoxy powder coatings are composed of epoxy resin, curing agents, pigments, fillers, and other additives. They are an early developed variety of thermosetting powder coatings, with excellent adhesion to metals, corrosion resistance, hardness, flexibility, and impact strength, and are widely used in various industries.