Electrospray coating apparatus and process utilizing precise control of

Abstract

An electrospray coating head system for applying thin coating to a substrate comprising a slot or blade to meter a liquid onto a shaping structure which forces the liquid to have a single continuous and substantially constant radius of curvature around the shaping structure. A voltage applied to the liquid around the shaping structure causes the liquid to produce a series of filaments which are spatially and temporally fixed, the number of filaments being defined by a simple adjustment in the applied voltage. The filaments break up into a uniform mist of charge droplets and are driven to a substrate by electric fields to produce a coating. Also a method for electrospray coating wherein liquid to be coated is dispensed from a metering portion to a lower shaping means where it achieves a single continuous and substantially constant radius of curvature, a voltage is applied to produce a series of filaments of the liquid which are spatially and temporally fixed, and the filaments break up into a uniform mist of charge droplets.