Wacker-chemie Gmbh

Christoph M&uuml;ller-Rees

Horst Leigeber

J&uuml;rgen K&uuml;pfer

Franz-Heinrich Kreuzer

Eckhard Hanelt

Georg Schwalb

The invention relates to a security marking whose level of proof against forgery is increased relative to known security markings, comprising liquid-crystalline material with chiral phase, wherein present within the security marking are at least two liquid-crystalline materials with chiral phase which differ in at least one property selected from the group consisting of handedness, color and color flop and which are arranged in the form of a structured or unstructured marking or a multilayer marking or in the form of liquid-crystalline pigments in a liquid-crystalline matrix, or wherein there is at least one liquid-crystalline material with chiral phase whose reflection band has been broadened by means of special techniques, or wherein there is at least one liquid-crystalline material with chiral phase which has a defined three-dimensional arrangement.

Machine-detectable security marking with an increased level of proof against forgery, production of the security marking, and security system comprising this security marking

The invention relates to mixtures containing pigments which comprise oriented three-dimensionally crosslinked substances having a liquid-crystalline structure with a chiral phase, and to the use of such mixtures. Pigment and matrix are matched to one another in such a way that on application of the mixture at different temperatures to a substrate, the lowest application temperature and highest application temperature differing by at least 10&deg; C. and by not more than 150&deg; C., there are no visually perceptible color differences of the pigmented paint on the substrate after drying.

Growing community of inventors

Pullach, Germany

Christoph Müller-Rees

Growing community of inventors

Pullach, Germany

Christoph M&uuml;ller-Rees

Christoph Müller-Rees