Abstract: Process and apparatus for applying a flowable coating medium to a travelling web by a reverse applicator roll technique in which the peripheral velocity of the applicator roll (U) is maintained at less than 0.4 of the forward speed of the web, and the dynamic viscosity of the coating medium (.eta.) is selected in accordance with the relationshiph=k.eta..sup.0.5 U.sup.0.5,wherein k is from 0.01 to 100, such that a layer of coating medium of equilibrium thickness (h) not exceeding 5.0 mm is entrained on the surface of the applicator roll for transfer to the web. The technique avoids the use of a doctor blade to meter the amount of coating medium on the applicator roll, and is suitable for the high speed application of a heat sealable coating layer onto a polymeric packaging film. Coating quality can be improved by stabilizing the web downstream of the applicator roll.

Abstract: Method and apparatus for simultaneously coating both surfaces of a moving web by a direct-indirect gravure technique in which the transfer roll of the indirect gravure system acts as backing roll for the direct gravure roll. The transfer roll is displaceable from the coating position to an inoperative position in contact with the indirect gravure roll to ensure that coating liquid does not form a dry layer on the surface of the transfer roll when the coating operation is interrupted and to remove the web from contact with either coating roll.