Low cost litho printing press, printing plate, and method for printing paste-type oil-based litho ink which eliminate the dampener and dampening solution therefrom

摘要

A litho printing press comprising one or more litho ink printing stations, each of which has paste-type, oil-based litho ink applicating means for depositing said oil-based litho ink onto a printing plate, an adjacent first rotatable cylinder called the plate cylinder on which is clamped a non-planar, laminate multiple layer flexible printing plate which receives said oil-based litho ink from the ink applicator means in a nip therebetween, and at least a second rotatable cylinder called the impression cylinder over which passes the substrate to be printed upon in a nip between the substrate and either the plate cylinder or another and intermediate rotatable cylinder called the blanket cylinder. This results in elimination of dampener and the dampening solution. The non-planar multiple layer flexible printing plate has an outermost layer for receiving the litho ink after it has been adhesively secured in the pre-press department of the printing plant to an innermost layer of a different material. The outermost layer is a see-through translucent or transparent synthetic plastic. The different material of the innermost layer can be either a synthetic transparent plastic or an imaged metal plate. In the pre-press department of the printing plant the outermost layer is cut through to the innermost layer manually or by a CAD-CAM machine to provide spaced cut-out areas with adjacent projections which receive the oil-based litho ink and then deposit said ink directly or indirectly on a substrate. The elimination of the dampening solution and the dampener from the print station by the non-planar laminate multiple layer flexible body printing plate, called a “Mike Plate” or “Modified Mike Plate” clamped on the plate cylinder makes possible a litho printing press without a blanket cylinder. That is, a litho printing press with only two cylinders per print station instead of three, and wherein said “Mike Plate” or “Modified Mike Plate” clamped on the plate cylinder prints directly upon the substrate, sheetfed or webfed. All this is done at low cost with less downtime on-press, and with significantly less waste and spoilage and other attendant benefits all of which contribute to quicker delivery of jobs by the printer to his customer.