Powder Coating

Powder coating is a method used to apply a decorative or protective coating to variety of materials in both industrial and commercial applications. The powder coating process involves the dry application of finely ground particles of pigment and resin to surfaces prior to a curing process. Unlike liquid coatings, each individual powder particle contains the entire coating formulation (pigment, resin, fillers, and modifiers); there are no solvents in powder coating. The applied powder material is then heated to a temperature sufficient to melt and cure the resin. After cooling, the coating is complete; there is no cure time beyond the cool-down period. Powder coating is by far the youngest of the surface finishing techniques in common use today. Powder coating is the process of applying dry paint to a part. In normal wet painting such as house paints, the solids are in suspension in a liquid carrier, which must evaporate before the solid paint coating is produced.
There are two main types of powder available to the surface finisher:

Thermoplastic powders that will remelt when heated, and Thermo setting powders that will not remelt upon reheating. During the curing process (in the oven) a chemical cross-linking reaction is triggered at the curing temperature and it is this chemical reaction which gives the powder coating many of its desirable properties.

The powder coating process involves three basic steps: