Physics of electrostatic painting

 

While all of us are aware that painting the surface improves its aesthetics, increases useable life, and prevents surfaces from erosion and rusting. While there are many ways a surface can be painted that range from using paint and brush, spray guns, and even use of painting furnaces. One of the latest technique in line  is electrostatic painting

Electrostatic paint prevents overspray and ensures an even and thin film of paint. It works by creating an electrostatic field between the object and the paint. An electric current is run through the spray nozzle that makes the paint moving through the tip acquire a negative charge. The object is connected to the supply via an earthed cable that gives the metal substrate a positive charge. This process makes negatively charged particles in the paint to be attracted to the positive coatings in the substrate. The object in a way acts similar to a  magnet, pulling the paint molecules to its surface, ensuring even disbursement. The thin film is formed that prevents wastage of paints due to overspray and results in a glossy thin layer of the painted surface

This method can be used for conducting surfaces. Though the initial cost of equipment is higher, it is gaining a lot of popularity due to its advantages over conventional spray paint.

Image Courtsey :plastics.gl