ELECTROSTATICALLY ASSISTED COATING METHOD AND APPARATUS WITHFOCUSED 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. An electrical force is created on the fluid from an effective electrical field originating from a location on the second side of the substrate and at a location substantially at and downstream of the fluid contact area. The electrical field can be generated in a highly effective manner relative to the coating fluid by a sharply defined electrode on the second side of the substrate. Ultrasonics combined with electrostatic fields further enhances coating process conditions and coating uniformity.