Patent ID: 6592669
Filing Date: 2003-07-15
Classification: B05C,D21H,Y10S

Abstract:
Apparatus for applying a coating liquid onto a surface of a moving web, comprising:a coating liquid applicator having an elongate outlet nozzle that is adjustable in width and an elongate coating liquid flow path leading to said outlet nozzle and having an elongate concave curved surface; means for pressure delivery of a sheet of coating liquid in which air is entrained to said flow path for flow therethrough and along said concave curved surface in an elongate sheet of coating liquid that, after flowing along said curved surface, is projected from said outlet nozzle in a free standing jet curtain of coating liquid toward, across, against and onto the surface of the web to provide an excess layer of coating liquid on the web surface, the coating liquid sheet, while flowing along said curved surface, being at a velocity that is sufficient, when taken together with the radius of curvature of said curved surface, to subject the coating liquid sheet to centrifugal force of a magnitude that causes air entrained in the coating liquid to move away from one side of the coating liquid sheet that is toward said curved surface and toward the opposite side of the coating liquid sheet, so that the one side of the coating liquid sheet is relatively free of entrained air, and said outlet nozzle being oriented relative the web so that an acute included angle exists between the one side of the coating liquid sheet and a tangent to the web at the point of contact of the sheet with the web, thereby to decrease the occurrence of skip coating on the web surface; and means for doctoring the excess layer of coating liquid on the web surface.