WO2004049268A1 - Security elements with combined machine-recognizable characteristics - Google Patents

Abstract

The invention relates to security elements with combined machine and/or visually recognizable characteristics, especially security characteristics with magnet and/or electrically conductive features.

Description

 Security elements with combined machine-recognizable features

The invention relates to security elements with combined machine and / or visually recognizable features, in particular security features with magnetic and / or electrically conductive features.

Security elements are used in many areas to ensure the counterfeit security of sensitive goods. For example, such security features are used in data carriers, in particular value documents, such as ID cards, cards, banknotes, in packaging materials for sensitive goods, such as pharmaceuticals, cosmetics, electronic components, in labels, seals and the like, for example in the textile industry.

DE -B 27 54 267 discloses security features with a magnetic coating, this magnetic coating being covered by a metal layer or by an opaque lacquer. This cover layer can act as a further visual security feature.

Security elements with magnetic properties are known from WO 99/04983, the magnetic layer being covered by a semitransparent layer.

The process for producing these security elements is relatively complex and has to be carried out costly via separate units. Inline production is not possible.

The object of the invention is to provide security elements with combined machine-recognizable security features.

The invention therefore relates to security features with combined machine-readable security elements, characterized in that the Security feature on a carrier substrate has both magnetic and electrically conductive coatings in one or more layers.

The layers are applied to a flexible carrier substrate.

The carrier substrate is, for example, carrier films, preferably flexible plastic films, for example made of PI, PP, MOPP, PE, PPS, PEEK, PEK, PEI, PSU, PAEK, LCP, PEN, PBT, PET, PA, PC, COC, POM, ABS, PVC in question. The carrier films preferably have a thickness of 5 to 700 μm, preferably 8 to 200 μm, particularly preferably 12 to 50 μm.

Furthermore, metal foils, for example Al, Cu, Sn, Ni, Fe or stainless steel foils with a thickness of 5-200 μm, preferably 10 to 80 μm, particularly preferably 20-50 μm, can also serve as the carrier substrate. The films can also be surface-treated, coated or laminated, for example with plastics, or painted.

Further, as carrier substrates also paper or composites with paper, for example, composites with plastics with a grammage 20-500 g / m ^2, preferably 40-200 g / m ^2. be used.

Furthermore, multilayer plastic films or film composites, for example composites made of metal and plastic films, can also be used as the carrier substrate.

A first functional layer made of a metal, a metallic printing ink, or an electrically conductive polymer is preferably applied to this carrier layer. This functional layer can be applied over the entire surface or partially. The metallic layer can be applied by vapor deposition, sputtering and the like and preferably consist of aluminum, silver, copper, iron, chromium and the like.

The metallic printing ink is preferably a printing ink containing metallic particles in a polymer matrix.

Examples of suitable polymer matrix are polyesters, polyvinyl alcohols, polyvinyl acetates, ethers, propionates and chlorides, poly (methyl) acrylates, ethylene acrylate copolymers, polystyrenes, polyolefins, nitrocellulose, polyisocyanates, urethane systems, epoxy resins and the like. The metallic printing ink can be solvent-free or water-containing or solvent-free and can optionally be reactively crosslinkable. Metal pigments (for example copper, aluminum, silver, gold, iron, chromium and the like), metal alloys such as copper-zinc or copper-aluminum or metal flakes, which already have functional features due to their layer structure (for example Al / Fe / Al ) are added.

To adjust electrical properties, for example conductivity, for example graphite, carbon black, conductive organic or inorganic polymers, metal pigments (for example copper, aluminum, silver, gold, iron, chromium and the like), metal alloys such as copper-zinc or copper-aluminum or amorphous or crystalline ceramic pigments such as ITO, ATO, FTO and the like can be added. Furthermore, doped or undoped semiconductors such as silicon, germanium gallium arsenide or selenium or ionic conductors such as amorphous or crystalline metal oxides or metal sulfides can also be used as additives. Polar or partially polar compounds, such as surfactants or non-polar compounds, such as silicone additives or hygroscopic or non-hygroscopic salts, can also be used or added to adjust the electrical properties of the layer. Paramagnetic, diamagnetic and also ferromagnetic substances such as iron, nickel and cobalt or their compounds or salts (for example oxides or sulfides) can be used to adjust the magnetic properties.

A magnetic pigment color based on oxidic pigments such as Fe ₂ O ₃ or Fe ₃ O ₄ , metal pigments such as iron, nickel, cobalt or chromium and / or their alloys, for example: Cr-Ni steel (stainless steel, is particularly suitable for setting the magnetic properties ), Barium or cobalt ferrites or the like. These pigments can be hard or soft magnetic.

The pigments are preferably dispersed in an aqueous or solvent-containing acrylate polymer dispersion (with a MW of 150,000-300,000) or in an acrylate-styrene or acrylate-urethane polymer dispersion. Water, alcohols such as i-propanol or methoxypropanol, esters such as ethyl acetate, ketones such as methyl ethyl ketone and mixtures thereof are suitable as solvents.

Different properties can also be combined by adding different additives mentioned above. It is possible to use colored and / or electrically conductive magnetic pigments. For example, such a magnetic pigment color can be made intrinsically conductive by selecting the appropriate pigments and corresponding concentration: for example, Fe ₃ O ₄ , carbon black, or metals, conductive ferromagnetic pigments, conductive steel pigments, optionally in a conductive polymer matrix. The concentration of the pigments can be about 0.01 - 30%.

By adding conductive materials, for example, carbon black, graphite or silver, the magnetic pigment color additionally has electrically conductive properties. As a result, two different functional features can be applied in one layer.

To set a specific color, the magnetic pigment color can be mixed with metallic alloys, for example aluminum or brass bronzes. However, the magnetic pigments are particularly advantageously colored by coating with metals, for example by vapor deposition or chemical deposition, by electroplating or coating.

Likewise, for example, pigments with optical properties can be coated with conductive and / or magnetic pigments, for example by vapor deposition, coating, chemical deposition and the like.

The metallic printing ink can be applied in any known method, for example by gravure printing, flexographic printing, screen printing, offset printing, digital printing, smooth roller, screen or line screen processes, in each case with co-rotation or counter-rotation, and the like.

The electrically conductive polymers can be, for example, polyaniline or polyethylene dioxythiophene.

The polymers can be applied to the carrier material in the form of a dispersion in a dispersant. Suitable dispersing agents are, for example, inert solvents, preferably aqueous solvents or alcohols, such as i-propanol. Optionally, matrix polymers, for example water-soluble polyesters, polyurethanes, polystyrene sulfonates, polyacrylates or ethylene acrylate copolymers, can also be added to the polymer dispersions as matrix polymers. For example, polyethylene dioxythiophene with polystyrene sulfonate can be used particularly advantageously as a matrix polymer. The particle size of the polymers in the dispersion is preferably 20-500 nm. However, it is also preferred to apply the soluble monomers or prepolymers to form the electrically conductive polymers and to polymerize them in situ. Both radical and redox or photoinitiators, for example UV initiators, can be used as catalysts.

The corresponding monomer or prepolymer is mixed with the catalyst and applied immediately to the carrier substrate.

Catalyst residues and other contaminating reaction products can also be removed in situ or, if appropriate, subsequently removed from the layer by treatment with a solvent, generally water. Volatile constituents can optionally also be removed by drying with an IR dryer, a convection dryer and the like.

The further functional layers are then applied to this first functional layer, which can be applied over the entire surface or partially, in the form of patterns, lines, geometric figures, characters, letters, numbers, a grid and the like, the further functional layers also in each case can be applied over the entire surface or partially, in the form of patterns, lines, geometric figures, characters, letters, numbers, a grid and the like.

The layers can be applied in register with one and / or several layers already present on the carrier substrate, but it can also be completely and / or partially overlapping with one and / or several existing layers.

For precise registration, the carrier web is provided with register marks and control lines and is, for example, sensors between two or more register marks of the upstream measuring device Measure the length and then set the required register length between two or more controlled train groups.Then the carrier web is controlled by a control circuit, in particular a register controller via a register roller in front of the first printing unit, the side register being pre-controlled via a web control and controlled via a swivel frame whereupon the layer is printed.

If necessary, the carrier web can be stretched between train groups or shrunk to the desired length, for example by heating with a convection dryer or IR radiator.

It is also possible to produce a multilayer structure by repeating individual layers several times. For example, an electrically conductive full-surface or partial layer can be followed by an optical layer and then an electrically conductive layer and then a layer with magnetic properties.

Examples of structures according to the invention are shown in FIGS. 1-9. Therein 1 means the carrier substrate, 2 an electrically conductive layer made of conductive silver or graphite or an electrically conductive polymer, 3 a layer with magnetic properties, for example made of a magnetic pigment paint, 4 a layer with combined magnetic and electrically conductive properties, 5 a high-gloss bronze layer with magnetic and / or electrically conductive properties, 6 a relase layer and 7 an optical layer, for example a layer with fluorescent properties.

In a preferred embodiment, a full or partial layer with combined electrically conductive and magnetic features is applied to the carrier substrate. This layer can then be covered over the entire surface or partially with a layer with optical properties, For example, a layer with luminescent, in particular fluorescent, properties can be applied.

In a further preferred embodiment, a high-gloss bronze layer can initially be applied to a carrier substrate, then a partial layer of an electrically conductive paint or an electrically conductive lacquer, then a full-surface or partial magnetic layer, which in turn can be covered over the entire surface or partially by a high-gloss bronze layer.

In a further preferred embodiment, a full or partial layer made of an electrically conductive polymer is applied to a carrier substrate, whereupon partial or full layers with magnetic properties and / or layers with electrically conductive properties are subsequently applied.

In a further preferred embodiment there is a partial relase layer between two functional layers. If this layer is detached or destroyed, the original properties of the functional layers are changed (for example the conductivity, the coding, the magnetic flux) and, as a result, tampering with the security element can also be detected.

Known poorly adhering paint compositions, for example based on methacrylate, are particularly suitable as release layers. Furthermore, very thinly applied oil layers, PE or fluoropolymer wax layers can also be used as the release layer.

The release layer is preferably partially applied to the carrier substrate. Any common printing method can be used to apply the release layer, preferably methods with which the thinnest layers of 0.01 to 50 μm can be applied exactly, for example spraying, Evaporation, spreading, roller application, deep flexo, screen, offset and digital printing and the like.

The structures according to the invention can then, for example, be partially or fully covered with a further layer, for example with optical features, or be provided with a further metallic coating, for example by vapor deposition or sputtering, electroplating and the like.

The layers can be made transparent as well as semi-transparent, translucent, screened or opaque. Furthermore, the electrically conductive and / or magnetic coatings can be reflective, transparent or semi-transparent.

Furthermore, the security elements according to the invention can be provided with a protective lacquer layer on one or both sides. The protective lacquer can be pigmented or unpigmented, with all known pigments or dyes, for example Ti0 ₂ , ZnS, kaolin, ATO, FTO, aluminum, chromium and silicon oxides or, for example, organic pigments such as phthalocyanine blue, indolide yellow, dioxazine violet and the like as pigments can be used. Furthermore, luminescent dyes or pigments which fluoresce or phosphoresce in the visible, UV or IR range, effect pigments such as liquid crystals, pearlescent, bronzes and / or multilayer color change pigments and heat-sensitive colors or pigments can be added. These can be used in all possible combinations. In addition, phosphorescent pigments can also be used alone or in combination with other dyes and / or pigments.

Furthermore, the security element according to the invention can be provided on one or both sides with a hot or cold seal adhesive or a self-adhesive coating for application to or for embedding in a substrate. It is also possible to laminate the security element with a further carrier substrate, which may have further functional layers.

The security elements according to the invention can advantageously be produced in an inline process, preferably in the gravure printing process, without interrupting the production process.

The security elements according to the invention are, if appropriate after assembly (for example into threads, strips, strips, patches or other formats), as security features in data carriers, in particular value documents such as ID cards, cards, banknotes or labels, seals and the like, but also in packaging material for sensitive goods, such as pharmaceuticals, cosmetics, data carriers, electronic components and the like.

Claims

claims: 1) Security features with combined machine-readable security elements, characterized in that the security feature has both magnetic and electrically conductive coatings in one or more layers on a carrier substrate. 2) Security features according to claim 1, characterized in that it has at least one layer with combined electrically conductive and magnetic properties. 3) Security features according to one of claims 1 or 2, characterized in that the security feature has at least a partial or full-area layer of electrically conductive polymers. 4) Security feature according to one of claims 1 to 3, characterized in that the security feature has at least one full or partial layer of a magnetic pigment paint or a magnetic pigment varnish. 5) Security feature according to claim 4, characterized in that the magnetic pigment paint or the magnetic pigment coating is based on oxidic pigments, metal pigments in an aqueous or solvent-containing acrylate polymer dispersion or in an acrylate-styrene or acrylate-urethane polymer dispersion. 6) Security feature according to claim 5, characterized in that the pigments of the magnetic pigment paint or the magenta pigment paint are colored by vapor deposition, by chemical deposition, by electroplating or coating. 7) Security feature according to one of claims 1 to 5, characterized in that a pigment with optical properties is coated by a pigment with magnetic and / or electrically conductive pigments by vapor deposition, chemical deposition, electroplating or coating. 8) Security feature according to one of claims 1 to 7, characterized in that the security feature has at least one layer of an electrically conductive printing ink. 9) Security feature according to one of claims 1 to 8, characterized in that the security feature contains at least one electrically conductive or magnetic layer made of a metal or an alloy. 10) Security feature according to one of claims 1 to 9, characterized in that the magnetic pigment paint or the magnetic pigment coating by adding Fe ₃ O ₄ , carbon black or metals, conductive ferromagnetic pigments, conductive steel pigments, optionally in a conductive polymer matrix in a concentration of 0.1 - 30% is set to be intrinsically conductive 11) Security feature according to one of claims 1 to 10, characterized in that the security features each have a plurality of layers with electrically conductive and / or magnetic properties. 12) Security features according to one of claims 1 to 11, characterized in that the electrically conductive and / or the magnetic layers are transparent and / or semi-transparent and / or reflective and / or opaque. 13) Security feature according to one of claims 1 to 12, characterized in that the security features have at least one layer with optical features. 14) Security element according to claim 13, characterized in that the layers) have optical properties iuminescent or thermochromic properties. 15) Security element according to one of claims 1 to 14, characterized in that the security element is provided on one or both sides with a protective lacquer layer. 16) Security element according to claim 15, characterized in that the protective lacquer layer is pigmented or unpigmented. 17) Security element according to claim 16, characterized in that the protective lacquer layer is colored and / or has iuminescent or iridescent properties. 18) Security elements according to one of claims 1 to 17, characterized in that it is laminated or connected to a further carrier substrate. 19) Security elements according to one of claims 1 to 18, characterized in that the further carrier substrate has functional and / or decorative layers. 20) Security elements according to one of claims 1 to 19, characterized in that the security elements are provided on one or both sides with an adhesive coating. 21) Security elements according to one of claims 1 to 20, characterized in that the security element additionally has a partial release layer between one or more functional layers. 22) Security element according to one of claims 1 to 21, characterized in that all layers of the security feature are applied in an inline process. 23) Security element according to one of claims 1 to 22, characterized in that the security elements are made up into threads, strips, tapes, patches and other formats. 24) Use of the security elements according to one of claims 1 - 23 as security features on and in data carriers, in particular value documents such as ID cards, cards, banknotes or labels, seals and the like, in packaging material for sensitive goods, such as pharmaceuticals, cosmetics, data carriers, electronic components and like.