Method for producing a printing block for moiré-free intaglio printing with sharply contoured lettering

摘要

A method for producing a moiré-free multicolour intaglio printed product with sharply contoured lettering from an indexed and initially unlettered offset image original by applying the lettering and subsequently optically scanning the image original which is clamped onto a scanning cylinder and bears the lettering, with an optic system of a scanning head which is set out of focus in order to avoid formation of the moiré effect and subsequent electronic conversion of the recorded light signals and engraving of an intaglio cylinder is simplified in that the lettering (11) is produced on a separate film (12) with a thickness such that the distance (a) of the lettering (11) of the film (12) which is laid on the offset image original (3) from the image layer (4) is exactly equal to the withdrawal path of the optic system (6) from the in-focus position of the image to the out-of-focus position, and in that the offset image original (3) is clamped onto the scanning cylinder (1) over the paper underlay (2), and the film (12) bearing the lettering (11), aligned with its lettering (11) at a distance (a) from the image layer (4) is clamped over said image original (3) and subsequently the scanning and engraving of the intaglio cylinder takes place with the optic system (6) of the scanning head (5) set in focus on the lettering (11). <IMAGE>