Electrostatic charge neutralization using grooved roller surface patterns

Abstract

A method for coating a liquid composition from an applicator to a first surface of a moving web having opposite first and second surfaces, the web being conveyed along a path through a coating apparatus, the coating apparatus including a charge neutralization station for neutralizing stray charges on the web, the charge neutralization station including a backing roller and means for depositing a charge on the web includes the steps of: wrapping the web in a partial wrap around the backing roller, the backing roller being provided with a conductive, relieved surface, the relieved surface having a pattern of circumferential grooves that provides venting of entrained air, the pattern having a geometry and depth such that any charge left on the web does not disturb the coating applied by the coating apparatus; providing a source of electrostatic charge at the charge neutralization station to neutralize any charge on the web; and transporting the charge neutralized web to a coating station, where a liquid composition is applied to the first surface, whereby the coating of liquid composition is not disturbed by stray electrostatic charges.