Ultrafine powder coatings, an innovation for the coating industry

Powder coating is an environmentally-friendly method for decorative and protective coatings, with clear advantageous over liquid coatings. However, only relatively coarse powders are used currently, leading to rough surface finishing and therefore limiting its application to low-end products such as under-hood components in automobiles. Although it is understood finer particles will provide much better surface quality, they cannot be used so far because the strong interparticle forces make them very cohesive and agglomerate badly. An ultrafine powder technology has been developed by our research group that allows the complete fluidization of ultrafine particles down to nanometer size. Using this technology, paint powders of 10-20 microns have been applied and high-quality surface finish comparable with liquid coating has been achieved, that is acceptable for the exterior of automobiles. Compared to the "regular" powder coating, the new technology gives an 80-90% reduction in surface roughness and also a 35-50% reduction in powder use, while maintaining the same surface protection.