BigPatents India

An improved sponge applicator and an improved contact coating apparatus for coating with liquid the outside surface of containers such as glass or plastic bottles is provided. The improved sponge applicator comprises an open cell foam having at least one surface for contacting and applying liquid to the container, and at least one section having a sealed surface for retarding flow of liquid from the sponge through the sealed surface and at least one unsealed surface for contacting the container, the sponge having an internal porosity allowing for flow of liquid through the open cell structure of the sponge. A method of sealing surfaces of an open-cell foam is also provided comprising swelling the foam with liquid, expelling excess liquid from the sponge and applying a sealant to the surface of the foam with liquid, expelling excess liquid from the sponge and applying a sealant to the surface of the foam while the foam is still in its welled shape, and curing the sealant on the sponge. An improved contact coating apparatus for bottles is also provided comprising means for rotating a container to be coated, a sponge coating applicator having several sealed surfaces and at least one unsealed surface, means for contacting the container with an unsealed surface of the sponge coating applicator, and means for supplying coating liquid to the sponge coating applicator.