ELECTROSTATICALLY ASSISTED COATING METHOD AND APPARATUS WITH FOCUSED ELECTRODE FIELD

摘要

A system for applying a fluid coating onto a substrate includes forming a fluid wetting line by introducing a stream of fluid onto a first side of the substrate along a laterally disposed fluid-web contact area. The apparatus of the present invention comprises a coating fluid applicator which dispenses a stream of coating fluid onto a first surface of the substrate to form a fluid wetting line along a laterally disposed fluid contact area, an electrical field applicator which applies an electrostatic field at a location on the substrate adjacent the fluid wetting line to attract the coating fluid to the first surface of the substrate, and an acoustical field applicator which applies an acoustical field at a location on the substrate adjacent the fluid wetting line. Ultrasonics combined with electrostatic fields further enhances coating process conditions and coating uniformity.