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~ Aug. 13,1946. _ KERN ' ' SQUARE FINISH PHOT — NGRAVED HALFTONE PRINTING PLATE AND THE METHOD OF MAKING ‘SAME Filed Sept. 2, 1943 2,4053% 2,4534 Patented Aug. 13, 1946 UNITED ‘STATES PTEZNT 2,405,749 SQUARE FINISH PHOTOENGRAVED HALF TONE PRINTING PLATE‘ AND THE METHOD OF MAKING SAME Lawrence Kern, Philadelphia, Pa. Application September 2, 1943, Serial No. 501,010 2 Claims. (0]. 101-4013) 2 1 My invention_relates to a new and useful square rounded by etched or engraved portions. .All of ?nish photoengraved halftone printing plate and . this is as usual and is produced in the well known the method of making same, and has for one of manner. Heretofore the material of. the plate has been its objects to provide an original halftone print cut away on the face by a beveler and a trim ing plate having a rounded edge. ming tool to define a border. This produces a Another object of the invention is to provide sharp outside edge and because of the natural a halftone printing plate in which the printing tendency of paper to sink down over these lower surface, composed of dots, is rounded along the edges, it requires additional work for the printer edges to produce shading off portions that result in soft line borders in the impressions. 10 to prevent the formation of a dark or black out line. At present the printer overcomes this dif Another object of the present invention is to ?culty, to some extent, by the “overlay” or “un provide a novel method of making a rounded edge derlay” which reduces the pressure along the on a halftone printing plate. edges but very often with unsatisactory results. A further object of my invention is to produce I completely overcome these difficulties and eliminate the use of “overlay” or “underlay” by beveling or cutting away portions of all of the the plate to form a relatively thin rim and turn edges of the plate at the back, as shown at ‘I, ing said rim down to form a depressed border Fig. 2, thereby forming a thin rim 8. This rim resulting in a rounded edge blending into the central printing surface. 20 8 is bent or turned down by applying pressure, through the medium of a suitable instrumentality A still further object of the invention is to pro 9, at or adjacent the margin of the rim, but re duce an original photo-engraved halftone print moved or spaced from the inner extremity of ing plate as an article of manufacture by a new the beveled or cut away portion, until the lower method which forms a rounded edge so that the printing surface dots gradually recede from the 25 or inner face of the outer portion of said rim becomes ?ush with or lies in the same plane as central printing area whereby an impression made the back of the main portion of the plate. This therefrom will have a soft gradually shading off produces the attaching ?ange l0 and the rounded border. edge l l between said ?ange and the central print With the above and other objects in View this ing surface. The rounded edge H thereby be invention consists of the details of construction, comes a de?nite part of said central printing sur combination of elements and the steps involved a rounded edge on a halftone printing plate by beveling or cutting away portions of the back of in the production of the printing plate, all here inafter described and then designated by the face and includes some of the raised area or dots so that an impression made from the plate has a soft outer edge because of the blending of the . In order that those skilled in the art to which 35 high lights with the vignettes without harsh, hard or sharp and de?nite lines of demarcation. this invention appertains may know how to make A printing plate made by my method is no more and use the same, I will describe a construction expensive than an ordinary one and is cheaper in detail and a method of producing such con in the long run because many more impressions struction, referring by numerals to the accom panying drawing forming a part hereof, in which: 40 can be obtained therefrom since, generally, the claims. Fig. 1 is a cross sectional view of a photo-en outer edge is the part of the plate that usually graved halftone printing plate made in accord ance with my invention. wears out fastest. A highly important feature of my invention is that the troubles usually ex graved halftone printing plates.v The printing as new and useful is: perienced by» printers with the sharp edge print Fig. 2 is an enlarged fragmentary sectional view of the plate after being beveled or cut away at 45 ing plate are automatically overcome when my rounded edge printing plate is employed. the back. Of course I do not wish to be limited to the Fig. 3 is a similar view after the rim has been exact details of construction herein shown and turned down to provide the?nished product, and described as these may be varied within the scope illustrating the ?nal step of the process. In carrying out my invention as herein em 50 of the appended claims without departing from the spirit of my invention. bodied, 5 represents a zinc or copper plate such Having described my invention what I claim as generally used for square ?nish photo-en 1. The method of producing a rounded edge on surface is composed of a multiplicity of so called “dots” 0 which, in effect, are raised areas sur 55 an original photo-engraved halftone printing 2,405,749 3 plate which consists in beveling the straight edge on the back of the plate, and then turning the edge down by suitable pressure on the printing surface to form a rounded edge that carries the dots over the edge until it softly removes itself automatically from printing contact. 2. An original photo-engraved halftone print ing plate provided with a printing surface on its front face, an inclined portion of said plate bor 4 dering the central portion thereof, and an at taching ?ange projecting from the inclined por tion, said flange and inclined portion being con structed from a thin rim produced by rabbeting the underside of the edge of the plate, which rim is subsequently bent to the desired con?gura tion. LAWRENCE KERN.