Curtain coating method and apparatus using dual wire edge guides
AssigneeEastman Kodak Company
InventorThomas C. Reiter
Life of this patent
Estimating the term…
Abstract
The present invention discloses edge guides (12) for use in guiding a curtain (17) of coating liquid onto a moving support. Each edge guide (12) is made of two or more small diameter wires (20) spaced apart a distance and running from the hopper lip (16) to the support web. The distance between the wires is approximately the thickness of the curtain. Flushing solution is introduced between the wires (20) near the hopper lip (16) and removed near the support web (15).
Claims25
A method of curtain coating a support with one layer of a liquid coating composition comprising:
- moving a support along a path through a coating zone;
- forming one or more layers of coating liquids to form a liquid coating composition;
- forming a free falling curtain from said liquid coating composition within said coating zone which extends transversely to said path and impinges on said moving support;
- laterally guiding said falling curtain by edge guides each of said edge guides having two or more wires extending from a point of formation of the falling curtain to the support, said two or more wires spaced apart a distance approximately equal to a thickness of the falling curtain;
- and
- providing a flushing means which contacts an edge region of said falling curtain and said two or more wires.
An apparatus for curtain coating a support with one or more layers of a coating liquid comprising:
- means for moving said support along a path through a coating zone;
- means for forming one or more layers of coating liquid to form a free falling curtain which extends transversely to said path and impinges on said support;
- edge guides, spaced apart a distance for laterally guiding said falling curtain, each of said edge guides comprising:
- a pair of wires spaced apart a distance, the distance being approximately equal to the thickness of the curtain, said pair of wires extending from forming means to the support;
- and
- flushing means for issuing a flushing solution near a top of each of said edge guides to maintain contact with said pair of wires and a main body of the curtain.
An apparatus for laterally guiding a falling curtain to a support comprising:
- at least one guide extending from a top of the falling curtain to the support said at least one edge guide formed from two or more wires spaced apart a distance, the distance being approximately equal to a thickness of the curtain;
- and
- flushing means for issuing a solution near a top of said at least one edge guide, the flushing solution maintaining wetting contact with the wires and a main body of the curtain.
An apparatus for curtain coating a support with one or more layers of a coating liquid comprising:
- means for moving said support along a path through a coating zone;
- means for forming one or more layers of coating liquid to form a free falling curtain which extends transversely to said path and impinges on said support;
- edge guides spaced apart a distance for laterally guiding said falling curtain each of said edge guides comprising:
- a solid land positioned at a bottom of said means for forming;
- flushing means for issuing a flushing solution at a bottom of said solid land;
- a pair of wires extending from the bottom of said solid land to a point of impingement on the support, said pair of wires spaced apart a distance, the distance being approximately equal to the thickness of the curtain wherein said flushing solution is in contact with said pair of wires and an edge region of said falling curtain;
- and
- suction means for extracting said flushing solution from said edge region of said falling curtain near the impingement of said falling curtain on said support.
An apparatus for laterally guiding a falling curtain to a support comprising:
- at least one edge guide extending from a top of the falling curtain to the support said at least one edge guide comprising:
- a solid land positioned near the top of the falling curtain;
- flushing means for issuing a flushing solution at a bottom of said solid land;
- and
- two or more wires extending from the bottom of said solid land to the support, said two or more wires spaced apart a distance, said distance being approximately equal to the thickness of the falling curtain wherein an edge region of said curtain contacts said solid land and then contacts the flushing solution, the flushing solution contacting said pair of wires.
Dependencies are inferred from the claim text.