GB578777A - Improvements in or relating to rotogravure printing members and method of making the same - Google Patents

Abstract

578,777. Intaglio printing cylinders. INTERCHEMICAL CORPORATION. May 10, 1943, No. 7378. Convention date, May 11. 1942. Addition to 535,076. [Class 100 (ii)] In an intaglio printing cylinder such as described in the parent Specification in which a thin printing plate is provided with inwardly bent flanges forming sharp edges with the printing surface so that there is no gap in the cylinder, the flanges are permanently secured together and the plate is provided with a backing member which holds the flanges and prevents rotation of the plate on the backing member. The plate is first placed on a former 17, Fig. 3, and its ends 15, 16 bent over, e.g. by hammering. The plate is then placed on a second former 22, Fig. 5, and clamped between members 25, 26 which form a guide for a wheel of the form shown which rolls the flanges, the upper member 25 having a recess 34 to receive excess metal. The wheel 30 is then replaced by a cylindrical or slightly tapered wheel 33, Fig. 6, and the member 25 may be replaced by a member 25A of the form shown, the edges of the flanges by this operation being formed with beads 36 of excess metal. The plate is then bent to cylindrical form in a two-part cylindrical member 40, Fig. 11, having a groove 45 to receive the beads 36. Before or.after removal from the member 40, the flanges are clamped and permanently secured together. The permanent fixing may be effected by forming one flange with snap button heads to engage openings in the other flange, by a U-shaped member 52, Fig. 8, having eyelets 53 pressed into holes in the flanges, by welding, or, as shown in Fig. 10, by casting a backing B on to the plate, the backing material also passing through openings in the flanges. The material of the backing may be metal, a thermoplastic, or a plaster such as gypsum. If the backing is not cast upon the plate, the plate is mounted on a backing having a groove to receive the flanges and an internal key to engage the printing cylinder mandrel. The beads 36 are removed by grinding and burnishing to produce an imperceptable joint.