Method for direct charging of the surface of an impression roll of an electrostatic assist gravure press

Abstract

A method and associated apparatus for applying a charge directly to an impression roll (12) which engages a gravure cylinder (14) of an electrostatic assist gravure press, wherein the improvement comprises the steps of placing a plurality of spaced contacts (26 or 54) capable of applying a charge to the impression roll (12) in direct contact with the surface of the impression roll (12), arranging the spacing between the contacts (26 or 54) and the width thereof so that predetermined groupings of the contacts (26 or 54) correspond to approximately the various web widths to be used with the gravure press, and controlling the charge applied by the contacts (26 or 54) to the surface of the immpression roll (12) to minimize the current leakage between the impression roll (12) and the gravure cylinder (14) in those areas of the impression roll (12) where the impression roll (12) directly engages the gravure cylinder (14) without the interposition of a web (22) therebetween.

Dependencies are inferred from the claim text.