US 12,269,286 B2
Security document including a transparent window formed in the substrate thereof
Arnaud Crassous, La Tour-de-Peilz (CH); Robert Stewart, La Tour-de-Peilz (CH); and Robert Stierman, Alphen aan den Rijn (NL)
Assigned to KOENIG & BAUER AG, Würzburg (DE)
Appl. No. 18/698,854
Filed by KOENIG & BAUER AG, Würzburg (DE)
PCT Filed Apr. 6, 2023, PCT No. PCT/EP2023/059177
§ 371(c)(1), (2) Date Apr. 5, 2024,
PCT Pub. No. WO2023/213495, PCT Pub. Date Nov. 9, 2023.
Claims priority of application No. 10 2022 111 099.0 (DE), filed on May 5, 2022.
Prior Publication US 2024/0326507 A1, Oct. 3, 2024
Int. Cl. B42D 25/324 (2014.01); B42D 25/29 (2014.01); B42D 25/351 (2014.01)
CPC B42D 25/324 (2014.10) [B42D 25/29 (2014.10); B42D 25/351 (2014.10)] 13 Claims
OG exemplary drawing
 
13. A security document comprising:
a substrate having a transparent window formed in the substrate;
a micro-optical structure composed of microlenses being arranged on a first side of the substrate, at least in a region of the transparent window, and a first print image being arranged on a second side of the substrate, located opposite the micro-optical structure, at least in the region of the transparent window;
the first print image including a plurality of image elements in a punctiform or linear grid;
a dot size or a line thickness of the image elements being smaller than a lens width of the microlenses arranged in the micro-optical structure;
a layer being arranged on and covering a part of the first print image, on a side of the first print image facing away from the micro-optical structure; and
a second print image being arranged on the layer covering the part of the first print image, on a side of the layer facing away from the micro-optical structure,
wherein the second print image is arranged on the layer covering the part of the first print image in such a way that the second print image can be brought into alignment with the micro-optical structure arranged on the first side of the substrate after carrying out a folding process at a bending line, in such a way that the second print image, or at least a piece of information contained therein, becomes visible and/or recognizable when viewed through the micro-optical structure, and
wherein:
the micro-optical structure is designed as a lens array or as a lenticular lens,
the lens array or the lenticular lens is composed of plano-convex microlenses,
when the micro-optical structure is the lens array, the plano-convex microlenses have at least one of a rotationally symmetric, spheric, or aspheric configuration, and
when the micro-optical structure is the lenticular lens, the plano-convex microlenses have an axially symmetric, rod-shaped configuration.