Patent ID: 6210757
Filing Date: 2001-04-03
Classification: B05C,B41F

Abstract:
The method of applying a coating material to a rotating grooved gravure roll by a coater that has a downstream blade and an arcuately spaced upstream blade, each blade placed against such a gravure roll, and each blade positioned in relation to the direction of rotation of such grooved gravure roll and whereby the coater has an intermediate gap-forming body between the blades, whereby an offrunning coating chamber is formed by the gap-forming body, the gravure roll, and the downstream blade, an onrunning coating chamber is formed by the gap-forming body, the gravure roll, and the upstream blade, and with the roll a gap is formed connecting such chambers, with fluid passageways opening into such chambers for the delivery or removal of liquid coating material therefrom, comprising the steps of:applying substantially air free liquid coating material under pressure to the passageway leading to said offrunning chamber and causing said liquid coating material to move through said gap into onrunning chamber, and causing an excess of such coating material to flow out through the passageway associated with said onrunning chamber;regulating the liquid pressure in said onrunning chamber at a relatively constant positive value, said pressure being sufficient to prevent air from entering the onrunning chamber as the gravure roll rotates past the upstream blade through said roll grooves; andregulating the liquid pressure in said offrunning chamber to control coating weight by means of controlling the rate of coating material flow into said offrunning chamber and the flow resistance of the gap leading to said onrunning chamber.