Method and device for coating the face of a roll in a film size press

Abstract

A method and device for coating of the face of a roll in a film size press with a coating agent by a coating device including a coating doctor that extends across the machine width and is loaded against the face of a roll in the film size press. The coating doctor spreads and smooths the coating agent, which has been introduced into the coating device and applied as a film onto the roll face before the coating doctor in the direction of rotation of the roll. To prevent the formation of streaks in the coating-agent film, in particular of streaks resulting from cavitation, adhesion of coating agent from the coating-agent film to the trailing side of the coating doctor is prevented by keeping the trailing side of the coating doctor moist or wet. Adhering of coating agent to the trailing edge of the coating blade is prevented by feeding a moistening medium as a constant flow to the area of the trailing edge. The moistening medium is introduced into the area of the trailing edge of the coating blade by spraying or atomizing.