Electrostatic painting of nonconductive surfaces with water base paints

The authors present a new painting method consisting of generating ultrasonically atomized electrically charged water particles behind the nonconductive surface to be painted. The paint spraying is carried out with a mechanical spray gun maintained at ground potential. The water-base paint becomes charged by induction under the influence of the space charge behind the nonconductive surface to be painted. As the resulting charge on the water-base paint particles is of opposite polarity to that of the ultrasonically atomized electrically charged water particle cloud, all propelling electric fields converge towards the surface to be painted. The results show excellent transfer efficiencies