Composite marking based on chiral liquid crystal precursors and modifying resins
AssigneeSicpa Holding SA
InventorsSabine Mayade, Tristan Jauzein
Life of this patent
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Abstract
Disclosed is a substrate which has thereon a marking or layer comprising a cured chiral liquid crystal precursor composition which does not contain any salt that would change the position of a selective reflection band exhibited by the cured composition. A modifying resin made from one or more polymerizable monomers comprising an average of at least one ether functionali typer polymerizable group is disposed between the substrate and the marking or layer and in contact with the marking or layer in one or more areas thereof. The modifying resin changes the position of a selective reflection band exhibited by the cured chiral liquid crystal precursor composition on the substrate in the one or more areas.
Claims18
A method of providing a marking on a substrate, wherein the method comprises:
- a) applying onto a surface of a substrate which carries a modifying resin made from one or more polymerizable monomers comprising an average of at least one ether functionality (—C—O —C—) per polymerizable group in one or more areas of the surface of the substrate a curable chiral liquid crystal precursor composition in such a way that the composition covers at least a part of the one or more areas carrying the modifying resin and also covers at least one area of the surface that does not carry the modifying resin,
- b) heating the applied composition to bring same to a chiral liquid crystal state;
- and
- c) curing the composition in the chiral liquid crystal state;
- and wherein the modifying resin increases a position of the selective reflection band exhibited by the cured chiral liquid crystal precursor composition on the substrate in the one or more areas in which it is present, provided that salt that would cause the increase of the position of the selective reflection band exhibited by the cured chiral liquid crystal precursor composition is not present in the composition.
A method of increasing a position of a selective reflection band exhibited by a cured chiral liquid crystal precursor composition comprising one or more nematic compounds and one or more chiral dopant compounds which are capable of giving rise to a cholesteric state of the cured composition and not comprising salt that would cause an increase of a position of the selective reflection band of the cured chiral liquid crystal precursor composition, wherein the method comprises contacting the composition with a modifying resin which is made from one or more polymerizable monomers comprising an average of at least one ether functionality (—C—O—C—) per polymerizable group and is capable of increasing the position of a selective reflection band exhibited by the cured chiral liquid crystal precursor composition.
Dependencies are inferred from the claim text.