Abstract: An improved extrusion-slide coating hopper for multi-layer coating of a substrate is described. The improved extrusion-slide coating hopper includes an upturned generally horizontally directed lip, which lip extends at an obtuse angle from an inclined slide surface and toward the substrate to be coated. A coating composition may be made to flow down the inclined slide and then upon the generally horizontally directed lip before being introduced on top of an extruded bridge of coating composition. The bridge of coating composition spans a generally horizontal gap between the hopper and the upwardly moving substrate. The apparatus of the invention improves upon coating apparatus of the prior art by providing, when coating, increased bridge stability and minimization of the deleterious effects of particles that lodge at an edge of the hopper.

Abstract: An improved coating apparatus of the kind wherein a coating hopper having a vertically inclined slide surface is provided, upon which one or more layers of a liquid coating composition(s) may be made to flow in a downwardly-inclined direction into a coating bead or bridge of coating solution which bridge spans a generally horizontal gap between an edge of the hopper and an upwardly moving substrate to be coated. In the apparatus of the invention, a coating composition(s) is made to flow over an upturned surface and toward the substrate, so that the coating composition(s) flows into the bridge of coating solution at an angle of lesser inclination to the horizontal than that of the slide surface. The apparatus of the invention improves upon coating apparatus of the prior art by providing, when coating, increased bead stability and minimizatin of the deleterious effects of particles that lodge at an edge of a coating apparatus.