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AssigneeXerox Corporation
InventorsWarren R. Smith, Gary W. Smallman, Kenneth A. Donahue, Mark Muscato
Estimating the term…
A coating system is disclosed comprising apparatus for coating webs comprising a rigid, elongated trough, a cylindrical applicator mounted for rotation about its axis within the trough, the trough having an arcuate upstream liquid retaining surface and an arcuate downstream liquid retaining surface closely spaced from the lower surface of the cylindrical applicator to define an arcuate coating zone which progressively narrows in the downstream direction, a manifold between the upstream liquid retaining surface and the downstream liquid retaining surface, the manifold extending substantially parallel to the axis of the cylindrical applicator, the arcuate downstream liquid retaining surface and the arcuate upstream liquid retaining surface extending from the manifold upwardly a sufficient distance along the periphery of the cylindrical applicator to retain most of any liquid in the coating zone, a wall at each end of the trough to retain the liquid in the coating zone, each of the walls being closely spaced from the adjacent end of the cylindrical applicator, and means for continuously introducing liquid into the manifold. A process for using this type of apparatus for coating webs is also disclosed.
A process for applying a coating to a moving web comprising providing an elongated trough, rotating a cylindrical applicator about its axis in contact with coating liquid having a viscosity of between about 1 centipoise and about 1,000 centipoises within said trough, said rotating being in a direction from upstream to downstream, said applicator having an upper surface and a lower surface, said cylindrical applicator being below and in contact with said web to carry coating liquid from said trough to said web, said trough having an arcuate upstream liquid retaining surface and an arcuate downstream liquid retaining surface substantially parallel to and spaced from the lower surface of said cylindrical applicator to define an arcuate coating zone which progressively narrows in the downstream direction, said arcuate upstream liquid retaining surface and said arcuate downstream liquid retaining surface being separated by a manifold extending substantially parallel to the axis of said cylindrical applicator, said arcuate downstream liquid retaining surface and said arcuate upstream liquid retaining surface extending from said manifold upwardly a sufficient distance along the periphery of said cylindrical applicator to retain most of said liquid in said coating zone, said arcuate downstream liquid retaining surface extending upwardly a greater distance than said arcuate upstream liquid retaining surface to compensate for a pumping action due to rotation of said cylindrical applicator spaced from said arcuate downstream liquid retaining surface, continuously supplying sufficient coating liquid to said arcuate applicator coating zone whereby said coating liquid coats the entire length of the lower surface of said cylindrical applicator and overflows out of the arcuate coating zone, and continuously introducing fresh coating liquid into said manifold at a rate greater than the rate at which said coating liquid is applied to said web.
Apparatus for coating webs comprising a rigid, elongated trough, a cylindrical applicator mounted for rotation about its axis within said trough, said rotation being in a direction from upstream to downstream, said applicator having an upper surface and a lower surface, said trough having an arcuate upstream liquid retaining surface and an arcuate downstream liquid retaining surface spaced from the lower surface of said cylindrical applicator to define an arcuate coating zone which progressively narrows in the downstream direction, a manifold between said upstream liquid retaining surface and said downstream liquid retaining surface, said manifold extending substantially parallel to the axis of said cylindrical applicator, said arcuate downstream liquid retaining surface and said arcuate upstream liquid retaining surface extending from said manifold upwardly a sufficient distance along the periphery of said cylindrical applicator to retain most of any liquid in said applicator coating zone, said arcuate downstream liquid retaining surface extending upwardly a greater distance than said arcuate upstream liquid retaining surface to compensate for a pumping action due to rotation of said cylindrical applicator spaced from said arcuate downstream liquid retaining surface, a wall at each end of said trough to retain said liquid in said arcuate coating zone, each of said walls being spaced from the adjacent end of said cylindrical applicator, at least one of said liquid retaining surfaces having an overflow lip at an upper end for overflow of liquid from said arcuate coating zone, and means for continuously introducing liquid into said manifold.
Dependencies are inferred from the claim text.