Electroformed thick-walled perforated sleeve - with mould release aided by inducing internal stresses

摘要

A thick-walled perforated cylindrical sleeve is mfd. by electrodeposition. A die is sensitised by deposition of a photosensitive layer and a pattern is copied on to this resin which is subsequently developed. Electrodeposition is then carried out. The contour and the density of the pattern points, the thickness and the treatment of the photosensitive resin, and the deposition conditions are studied as a function of the desired thickness without significantly deforming the pattern points and hence the perforations. The mould is removed using internal stresses b uilt up in the deposited metal, these stresses being controlled throughout the deposition in a range with a maximum at which peeling occurs during deposition and with a minimum at which removal from the mould is not possible without plastic defomation taking place and deterioration of the sleeve. The roll or sleeve can be used to impart a relief or cover with a protective varnish a design previously printed in several colours.