METHOD AND APPARATUS FOR APPLYING A FILM OF FLUID ONTO A FLAT SURFACE AND SPECIFICALLY ONTO A LITHOGRAPHIC PRINTING PLATE IN A DEVELOPING STATION

摘要

The invention relates to the application of a uniform film of a fluid to the surface of a flat workpiece as it is being conveyed through a workstation. The invention is specifically directed to the development of lithographic printing plates and comprises the application of the thin film of developer solution to each plate in a controlled manner using a wire-wound coating device and a unique manner of metering and feeding fresh fluid to the wire-wound device. Specifically, the fluid is gently fed onto the wire-wound device by simple volumetric displacement and overflow from the inside of a hollow tube onto the wire and the flow is controlled by sensing the beginning and end of each workpiece or plate. The hollow tube may be the wire-wound component or it may be a tube mounted above the wire-wound component. The developer is allowed to dwell on the plate as it is conveyed across a support structure for a sufficient time to allow for percolation into and/or dissolution of the soluble areas of the coating.