GB704742A - Improvements in or relating to method of correctly fitting printing plates on printing cylinders or flat printing plate supports - Google Patents

Abstract

704,742. Printing surfaces. KREGLEWSKI, E. March 16, 1948 [March 18, 1947], No. 7850/48. Drawings to Specification. Class 100 (2) In a method of adhesively fastening a plurality of printing plates of rubber or other elastic material with exact register on plate cylinders or flat plate supports, registering elements adapted to print register rings are provided on the printing plates, and sheets printed from the plates and bearing the said rings are arranged in the required positions on and attached to the uppermost of a plurality of superposed lining sheets, after which register holes serving for the reception of locating pins are punched simultaneously through all the lining sheets at the places where the rings are on the printed sheets, locating pins being then inserted in the holes in the respective lining sheets, register holes adapted to receive the pins being also punched through the registering elements on the plates, whereupon the respective plates are located in the correct positions by means of their holes and the pins, either on the lining sheets themselves or on the cylinders or flat supports after the pins have been temporarily attached thereto while located in the correct positions thereon by means of the lining sheets, the plates then being attached to the lining sheets or the cylinders or flat supports respectively, and the pins removed therefrom. Example 1, for attachment of plates to cylinders having means for the attachment of linings thereto. The linings are provided with a row of perforations along their leading edges for attachment by means of a series of pins to a work table, and also for attachment to the cylinder. For four-colour printing, four linings are secured upside-down to the table, being secured at their trailing edges by glued strips. The printed copies of the main colour are attached to the top lining by small glued strips in positions corresponding to the layout of the printed sheet. The holes are then made by a perforating device, the copies removed, the linings turned over on the table and the pins passed through the holes in the top lining from the underside. The appropriate plates are then placed on the top lining with the pins passing through the holes in the plates, and fixed to the lining. The lining and plate are removed from the table and passed with the pins withdrawn, round the cylinder. The appropriate plates for the various colours are then similarly fixed to each lining in turn. Alternatively, the lining is secured by its edge to the cylinder, the pins inserted from the underside, the lining rolled on to the cylinder, and the plates fixed to the lining, the lining unwound and the pins removed. For printing on both sides for example, with three colours on one side and two on the other, three linings are placed the right side up on the table, and then two linings upsidedown. Example 2, for attachment of plates to flat plate supports. The pins are provided with pieces of bilaterally glued strips. After the pins have been passed through the holes in the top lining, the latter is placed on the support, and the strips secure the pins to both the lining and the support. The lining is then cut away round the pins and removed, and the plates placed over the pins on to the support. The plates are stuck to the support by adhesive strips, and after nearly their whole area is secured, the ends are raised and the pins removed. Example 3, for attachment of plates to cylinders not having means for the attachment of linings thereto. The plates are fixed directly to the cylinders as in example 2, the linings being applied to the cylinders and cut away.