Patent ID: 8834334
Filing Date: 2014-09-16
Classification: B41F,B41M,B65H

Abstract:
1. Method of controlling the register, between a printed pattern and a non-printed pattern, with high accuracy, on a running material web, comprising: a) printing at least one printed pattern and at least one, printed, two-dimensional, register mark on the web, b) creating a non-printed pattern or recurring feature on the web, steps a) and b) being carried out in any order, c) simultaneously, and in synchronisation with the operation of carrying out step b), impressing an indentation having a three-dimensional topographic configuration such that a shadow is created from the indentation when illuminated, on the web at a pre-determined distance from the printed register mark, the indentation thereby producing a dark spot when illuminated, d) determining the position of the said shadow or dark spot relative to the position of the printed mark by illuminating and detecting with an optical sensor system, the shadow being detectable by the same optical sensor system as used for detecting the printed mark, e) comparing the value of the measured position of the shadow created from the impressed indentation relative to the position of the printed mark with a pre-set value, and f) regulating the operation of creating said non-printed pattern or recurring feature as well as said synchronised, impressed indentation and/or regulating the printing operation, in order to adjust the measured value to the pre-set value.