Patent ID: 8351087
Filing Date: 2013-01-08
Classification: B42D,B44F

Abstract:
1. A method for creating counterfeit-resistant valuable documents and articles relying on a compound layer displaying a dynamically evolving moire shape, said compound layer comprising an s-random base layer and an s-random revealing layer, the method comprising the steps of: a) generating the element positions of the s-random base layer according to base layer layout parameters and base layer s-random displacement values; b) generating the element positions of the s-random revealing layer according to revealing layer layout parameters and s-random displacement values derived from said base layer s-random displacement values; c) creating the s-random base layer by associating to each position in the layout of the s-random base layer an instance of a base layer element shape; d) creating the s-random revealing layer by associating to each position in the layout of the s-random revealing layer an instance of a revealing layer sampling element; e) forming the compound layer by superposing the resulting base and revealing layers with a gap between them; and f) integrating the compound layer onto the valuable document, respectively article; where the compound layer shows, due to the superposition of said s-random base and revealing layers, a single moire shape instance which, when tilting the compound layer in respect to the observation orientation, undergoes a dynamic evolution comprising elements selected from the set of scalings, shearings, rotations, and movements along a trajectory determined by the base layer and revealing layer layout parameters.