1, the basic situation of the industry:

(1) Introduction of powder coating: powder coating is mainly composed of resin, curing agent, pigment, filler, additives and other mixed solid powder, through electrostatic spraying, fluidized bed dip coating method and other methods coated on the surface of the coated object, and then baked to melt leveling, curing film. Because it does not contain any organic solvent, no pollution, high utilization rate, low energy consumption and simple process, powder coating has become a recognized "4E" (high efficiency, energy saving, environmental protection and economic) coating. In addition, powder coating itself has the advantages of high mechanical properties, excellent chemical resistance, corrosion resistance and labor intensity reduction. Therefore, powder coating has been paid attention to by all countries since its introduction, become the new darling of the paint market.

China Powder Coatings Market Research and Investment Proposal Forecast Report 2022-2028 published by CICC International Consulting

Powder coatings are generally composed of resins, curing agents, pigments, fillers and additives. The basic film-forming substances of thermosetting powder coatings are resins and curing agents. In addition, pigments, fillers and additives are also important components of powder coatings.

Resin: Resin is the main film-forming substance of powder coating, accounting for the largest proportion. The quality of the powder coating depends largely on the quality of the matrix resin. The resin has a great influence on the appearance, physical properties and storage stability of the powder coating, and is the main raw material of the powder coating. The resin used to make powder coatings has more performance requirements:

A. The resin should have the performance of chemical reaction with the curing agent to form a film under certain temperature conditions, and the film-forming material has good physical and mechanical properties and chemical resistance.

B, resin and curing agent, pigment, filler and additives such as powder coating other components of the compatibility and dispersion is good, easy to manufacture powder coating.

C, the softening point of the resin temperature control. The higher the softening point, the higher the melt viscosity of the resin, the worse the leveling property after the resin film formation, and the poor decorative effect. If the softening point is too low, the storage stability of the powder coating is not good, and it is easy to agglomerate, which is not conducive to the construction of electrostatic spraying.

D, the molecular weight of the resin control. If the molecular weight of the resin is too high, the mechanical properties of the resin coating film are excellent, but it is not conducive to processing, and the leveling performance of the coating film is poor, and the surface decoration effect is not good; if the molecular weight of the resin is too low, the leveling performance of the resin coating film is excellent, but the mechanical properties, chemical resistance and other properties of the coating film are not good. Therefore, the resin must have a relatively moderate molecular weight.

② curing agent: thermosetting powder coatings used in the matrix resin and curing agent must be cross-linked to form a film to meet the requirements of its application performance, so the choice of curing agent on the coating performance also has a greater impact. Common curing agents include epoxy, TGIC, HAA, IPDI, etc.

Pigments and fillers: Pigments and fillers are also an important part of powder coatings. The main role of pigments is to increase the decorative effect of the coating, and the role of fillers is to reduce the cost of powder coatings and improve the mechanical properties of the coating.

Although the proportion of additives in the powder coating is very low, it is an indispensable part of the powder coating formulation. The appearance of the coating film can be changed due to the addition of additives. Commonly used additives are: leveling agent, coating brightening agent, curing accelerator, matting agent, pattern additives, etc.

According to the different types of resins used in powder coatings, powder coatings can be divided into two categories, one is thermoplastic powder coatings prepared from thermoplastic resins, and the other is thermosetting powder coatings prepared from thermosetting resins. Since thermoplastic powder coatings generally use thermoplastic resins with relatively large molecular weight, this characteristic leads to strong resin toughness, difficult crushing, high softening temperature, high melting temperature, poor leveling, and poor adhesion, which limits its application. Thermosetting powder coating is a relatively small molecular weight thermosetting resin, at a certain temperature, with the curing agent for crosslinking reaction, the formation of a network structure of macromolecular coating. Compared with thermoplastic powder coatings, thermosetting powder coatings have good performance, large output and wide application range. At present, domestic thermosetting powder coatings occupy an absolute dominant position in the powder coating market.

China's thermosetting powder coatings can be divided into: pure epoxy type, epoxy/polyester mixed type, pure polyester type according to the film-forming material (resin) used; pure polyester type is divided into TGIC curing type, HAA curing type and IPDI curing type.