Wacker-chemie Gmbh

Consortium Fur Elektrochemische Industrie Gmbh

J&uuml;rgen K&uuml;pfer

Horst Leigeber

Franz-Heinrich Kreuzer

Christoph M&uuml;ller-Rees

Eckhard Hanelt

Norman H&auml;berle

Georg Schwalb

Michael Kasch

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

A mixture of crosslinkable liquid-crystalline substances having a chiral phase (LC mixture), containing polymerizable groups, where at least 90% of the polymerizable groups are part of molecules containing at least two polymerizable groups (crosslinker molecules), wherein from 3.2 to 15 mmol of polymerizable groups are present per g of LC mixture. The crosslinked pigments show little color shift in the presence of solvents or upon application to substrate different temperatures.

Thermostable pigments, films and effect coatings, and mixtures for their production

Liquid-crystalline silicones having increased UV stability

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.

Mixture comprising pigments having a liquid-crystalline structure with a chiral phase and its use

Growing community of inventors

München, Germany

Jürgen Küpfer

Growing community of inventors

München, Germany

J&uuml;rgen K&uuml;pfer

Jürgen Küpfer