Electro-optical security element

Abstract

The invention relates to a security element for a security and/or valuable document, comprising a matrix based on an organic polymeric material, at least one electrically conductive pigment dispersed in the matrix, and at least one organic luminescent substance dispersed in the matrix, which luminescent substance is capable, in the presence of the conductive pigment, of non-contact excitation of light emission, and the particle size of which is less than 200 nm, wherein the luminescent substance is not encapsulated, and is directly surrounded by the matrix and is embedded therein, and to uses of such a security and/or valuable document and to security and/or valuable documents produced by such uses.

1 . A security element for a security and/or valuable document, comprising a matrix based on an organic polymeric material, at least one electrically conductive pigment dispersed in the matrix, and at least one organic light-emitting semiconductor dispersed in the matrix, which semiconductor is capable, in the presence of the conductive pigment, of non-contact excitation of light emission, and the particle size of which is less than 200 nm, wherein the organic light-emitting semiconductor is not encapsulated, and is directly surrounded by the matrix and is embedded therein. 
     
     
         2 . The security element according to  claim 1 , wherein the organic polymeric material is selected from the group consisting of PC (polycarbonate, particular bisphenol A polycarbonate), PET (poly-ethylene glycol terephthalate), PMMA (polymethyl methacrylate), TPU (thermoplastic polyurethane elastomers), PE (polyethylene), PP (polypropylene), PI (polyimide or poly-trans-isoprene), PVC (polyvinyl chloride), polystyrene, polyacrylates and methacrylates, vinyl acetate, ABS and copolymers of such polymers, preferably is a polycarbonate derivative, in particular based on bisphenol A, preferably based on a geminally disubstituted dihydroxybiphenyl cycloalkane. 
     
     
         3 . The security element according to  claim 1 , wherein the organic light-emitting semiconductor is an OLED material, wherein the organic light-emitting semiconductor is preferably non-particulate, and preferably homogeneously dispersed, in particular dissolved in the matrix. 
     
     
         4 . The security element according to  claim 1 , wherein the electrically conductive pigment is platelet-shaped, in particular with an aspect ratio of at least 2:1, and a mean particle diameter from 1 to 500 μm, and preferably is transparent, or a nanorod or a nanotube. 
     
     
         5 . The security element according to  claim 1 , further comprising at least one charge carrier transport material. 
     
     
         6 . The security element according to  claim 1 , additionally comprising one or a plurality of substances or materials selected from the group consisting of color pigments, effect pigments, optically variable pigments, UV blockers, preservatives, and stabilizers. 
     
     
         7 . The security element according to  claim 1  in the embodiment as a printing layer or film, wherein the security element (if applicable, after drying) preferably contains:
 A) 0.1 to 5 wt-% organic light-emitting semiconductor, 
 B) 60 to 95 wt-% matrix, 
 C) 2 to 15 wt-% electrically conductive pigment, 
 D) 0 to 37.9 wt-% additives and/or pigments different from C), 
 the relative amounts of the components A) to D) always totaling 100%. 
 
     
     
         8 . A printable composition, in particular a printing ink, for the production of a security element according to  claim 1 , comprising an organic polymeric material, at least one electrically conductive pigment, at least one organic light-emitting semiconductor, which is capable, in the presence of the electrically conductive pigment, of non-contact excitation of light emission, and at least one aqueous and/or organic solvent, wherein the organic light-emitting semiconductor is not encapsulated and has a particle size less than 200 nm. 
     
     
         9 . A preparation according to  claim 8 , further comprising at least one charge carrier transport material. 
     
     
         10 . The preparation according  claim 8 , additionally comprising one or a plurality of substances or materials selected from the group consisting of color pigments, effect pigments, optically variable pigments, UV blockers, preservatives, rheology-modifying agents, and stabilizers. 
     
     
         11 . A security and/or valuable document, comprising a substrate layer, optionally one or a plurality of additional layers, and at least one printing layer or film according to  claim 8 , wherein the printing layer or film is applied over the entire surface or over part of the surface of the substrate layer or an additional layer. 
     
     
         12 . A method for producing a security and/or valuable document according to  claim 11 , wherein the substrate layer and/or the additional layer is formed from a paper material or an organic polymeric material, wherein on the substrate layer or the additional layer, a printing layer or film according to  claim 7  is applied, and wherein, if applicable, said substrate layer and additional layer, optionally with a cover layer, are laminated together, before or after the application of the printing layer or film. 
     
     
         13 . A method of verification of a security and/or valuable document according to  claim 11 , wherein the security and/or valuable document is exposed to physical conditions, which, in presence of the electrically conductive particles, stimulate the organic light-emitting semiconductor to emit light, wherein the light emission is observed or measured, and wherein the security and/or valuable document, in accordance with the observation or measurement, is classified as genuine or forged.