Electrospray coating apparatus and process utilizing precise control of filament and mist generation

A method of variably controlling the uniform emission of a liquid being applied as a coating material in an electrospray coating process, comprising the steps of:

• a) providing a metering portion for dispensing liquid to a lower shaping means;
• b) positioning lower shaping means below said metering portion such that dispensed liquid flows from said metering portion onto said lower shaping means so as to surround said lower shaping means, creating a layer having a single continuous and substantially constant local radius of curvature of the dispensed liquid around the lower shaping means so that the number and position of filaments of said liquid extending from the lower shaping means is variable depending on the magnitude of a potential applied to the surface of the liquid surrounding the lower shaping means;
• and
• c) adjusting the potential applied to the surface of the liquid so that a specific potential produces a desired number and position of filaments of said liquid and so that at a specific potential said liquid filaments are spatially and temporally fixed to permit generation of a uniform mist of highly charged droplets.

A method of variably controlling the emission of a liquid being applied as a coating material in an electrospray coating process, comprising the steps of:

• a) providing a metering portion for dispensing liquid to a lower shaping means;
• b) positioning lower shaping means below said metering portion such that dispensed liquid flows from said metering portion onto said lower shaping means so as to surround said lower shaping means, said lower shaping means creating a layer having a single continuous and substantially constant local radius of curvature of the dispensed liquid around the lower shaping means so that the number and position of filaments of said liquid extending from the lower shaping means is variable depending on the magnitude of a potential applied to the surface of the liquid surrounding the lower shaping means;
• c) adjusting the potential applied to the surface of the liquid so that a specific potential produces a desired number and position of filaments of said liquid and so that at a specific potential said liquid filaments are spatially and temporally fixed to permit generation of a uniform mist of highly charged droplets;
• and
• d) directing the flow of the mist toward selected deposition sites on a movable substrate.