The theory and practice of electrostatic spraying

Important developments in electrostatic spray theory, sprayers relying solely on electrostatic forces and hybrid spray systems that have occurred during the last decade, are reviewed. Electrostatic spraying depends upon liquid electrical resistivity, except for those spray systems that operate by charge injection into the liquid phase prior to dispersion. Spraying of liquids may produce ions, highly charged submicron-sized drops or large charged drops. Numerous applications for charged ions or drops have been developed, ranging from ion sources for spacecraft propulsion, microscopy, implantation, sputtering and micromachining to charged drop sprays for maskless pattern generation, thin-film coating, the production of ultrafine powders, lubrication, emulsification, crop spraying, paint spraying and fuel-spraying control. A comprehensive range of references is cited.