Sheet material for security elements in the form of film patches

Abstract

Method for producing film material for security elements in the form of film patches (4), comprising the following steps to be carried out in the order mentioned: - Applying a first plastic film (1), which is web-shaped, to a web-shaped carrier substrate (3), wherein the first plastic film (1) is bonded to the carrier substrate (3) by means of prior electrostatic charging, prior corona treatment or by means of a release coating containing a UV-crosslinking release layer (5), - Applying at least one security feature (7), which is optically detectable and / or machine-readable, to the first plastic film (1), - Applying a second plastic film (2), which is web-shaped, or a protective lacquer layer (9) to the at least one security feature (7), - Applying an adhesive layer (10), in particular heat-activated, to the second plastic film (2) or to the protective lacquer layer (9).

Description

AREA OF INVENTION

[0001] The invention relates to a method for producing foil material for security elements in the form of foil patches, as well as foil material produced accordingly and security elements in the form of a foil patch. STATE OF THE ART

[0002] Security and valuable documents protected with security elements in the form of so-called patches, more precisely foil patches, featuring optically variable security features such as holograms, kinegrams, motion images, color-shifting effects, and the like, have been known for a long time. These optically variable security features are often produced using hot foil stamping technology, and the resulting foil patches are applied to security papers or valuable documents made of paper, polymer, or hybrid materials using appropriate application devices. Unlike security strips, foil patches are not limited to a specific geometry and, due to their geometric diversity, can be integrated more easily and harmoniously into the design concept of a security or valuable document, such as a banknote.

[0003] With increasing demands on circulation, chemical and physical resistance, and counterfeit protection, traditional hot stamping foil technology for foil patches is proving insufficient. This is particularly true for so-called window banknotes, where a foil patch is applied over a "window." This window is either an opening in the banknote material that is closed by the foil patch, or a transparent area in the banknote material onto which the foil patch is applied. Foil patches are also used on polymer banknotes, where the banknote material is primarily plastic. Experience has shown that the thermoplastic hot stamping foils used for these foil patches are the weakest link in terms of durability, crease resistance, and abrasion resistance.

[0004] From EP 286004281 A1, a method is known in which a film is cut to size for a window area formed as an opening and fixed in the opening with a cover film. Cutting and applying the films is very complex.

[0005] EP 3505361 A1 discloses foil patches arranged on a carrier tape and a method for patching windows in a document substrate. The foil patches must be equipped with permanently adhesive adhesives for bonding to the document substrate and also with release agents for removal from the carrier tape. The latter negatively impacts both the firm, permanent bond to the document substrate and impairs the adhesion of any printing inks applied over the foil patch, particularly in intaglio or offset printing.

[0006] WO 2021069096 A1 shows two variants of how a security feature transfer material can be bonded to a temporary carrier, i.e., a carrier substrate. In the first variant, a coextruded film is used, with one layer of this composite film acting as the carrier substrate and another layer as the plastic layer of the security feature transfer material, whereby both layers are prone to delamination. In the second variant, a coextruded film is used as the carrier substrate, which is detached as a release layer from the security feature layer composite, specifically from a UV embossed varnish layer.

[0007] The first option has the disadvantage that only certain pairings of different plastics result in a co-extruded film, where the different plastics then tend to delaminate. The second option has the disadvantage that the UV embossed lacquer layer is located on the outside of the final security element, leaving it unprotected against external influences as an optically effective layer. PRESENTATION OF THE INVENTION

[0008] One object of the invention is to produce a foil material for foil patches with optically recognizable and / or machine-readable security features, which can securely seal windows in banknotes or other security and valuable documents and meets the requirements for durability and, with regard to banknotes, their circulation suitability, in particular better than hot stamping foils. Furthermore, the foil patches should be removable from the rest of the foil material with as little residue as possible. Preferably, the foil material should be processable on commercially available application equipment, i.e., the foil patches should be die-cut on commercially available equipment and applied to a security or valuable document.

[0009] This problem is solved by a method according to claim 1. This method comprises a method for producing film material, namely film material for security elements in the form of film patches, comprising the following steps to be carried out in the stated order: Applying a first, web-shaped plastic film to a web-shaped carrier substrate, wherein the first plastic film is bonded to the carrier substrate by means of prior electrostatic charging, prior corona treatment or a releaseable coating containing a UV-crosslinking release layer, applying at least one security feature that is optically detectable and / or machine-readable to the first plastic film, applying a second, web-shaped plastic film or a protective lacquer layer to the at least one security feature, and applying an adhesive layer, in particular one that is heat-activated, to the second plastic film or to the protective lacquer layer.

[0010] Further steps may be taken between the aforementioned steps, for example for the insertion of a region-specific liability control layer or for the insertion of further security features.

[0011] The substrate can be opaque, transparent, or translucent. Papers, coated papers, or polymer films can all be used. If the first plastic film is applied by prior electrostatic charging or corona treatment, the substrate should have a surface finish and / or smoothness, at least on the side facing the first plastic film, to ensure adhesion. Suitable substrates include PET films or PE-coated kraft papers.

[0012] Flexible plastic films are also suitable as carrier substrates, for example those made of polyimide (PI), polypropylene (PP), monoaxially oriented polypropylene (MOPP), biaxially oriented polypropylene (BOPP), polyethylene (PE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), polyetherketone (PEK), polyethyleneimide (PEI), polysulfone (PSU), polyaryletherketone (PAEK), polyethylene naphthalate (PEN), liquid crystal polymers (LCP), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyamide (PA), polycarbonate (PC), cycloolefin copolymers (COC), polyoxymethylene (POM), acrylonitrile butadiene styrene (ABS), polyvinyl chloride (PVC), ethylene tetrafluoroethylene (ETFE), polytetrafluoroethylene (PTFE), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF). Ethylene tetrafluoroethylene hexafluoropropylene fluoropolymers (EFEP), cellulose- or lignin-based plastics, polyhydroxyalkanoates (PHA), thermoplastic starch (TPS), polylactic acid (PLA), polycaprolactone (PCL),Polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and / or made from at least one recycled and / or biodegradable and / or marine-degradable plastic, and / or from mixtures and / or copolymers of these materials. The carrier substrates, in particular carrier films, can be transparent, translucent, semi-opaque, or opaque.

[0013] The support substrate preferably has a thickness of 5-700 µm, preferably 5-200 µm, particularly preferably 5-50 µm.

[0014] The first plastic film is the same width as the carrier substrate, and in particular, it will have the same width. The width of the carrier substrate corresponds at least to the width of one film patch, but usually to the width of several film patches spaced apart. After the film patches have been produced and the carrier substrate removed, the first plastic film protects the subsequent safety feature in the layer sequence from external influences. The first plastic film is preferably transparent.

[0015] In principle, most PET films are suitable for carrying out the invention. In particular, the first plastic film can be a PET film with a thickness of 3 µm to 15 µm, preferably 6 µm to 8 µm. PET films are especially well-suited for capacitor production due to their defect-free and pure nature. These so-called capacitor films are generally biaxially oriented PET films. Examples of capacitor films, which exhibit low shrinkage values ​​at high temperatures, are shown in DE 19736398A1. Capacitor films are therefore particularly advantageous for embodiments with electrostatic charging and corona treatment.

[0016] The advantage of electrostatic charging lies in the fact that no material needs to be placed between the substrate and the first plastic film, thus saving a corresponding work step. Furthermore, no residue remains on the first plastic film after it is separated from the substrate, allowing for optimal printing. The adhesion resulting from the prior electrostatic charging is further enhanced by the glass plate effect, which occurs between the smooth surfaces of the substrate and the first plastic film.Electrostatic charging and the glass plate effect bond the substrate and the first plastic film so firmly and permanently that the resulting film composite can be processed efficiently and economically. However, when the resulting film patches are later applied to security or valuable documents, they can be easily separated from each other without leaving any residue on the first plastic film. Generally, either the substrate (for example, in the case of multilayer substrates, the layer facing the first plastic film) or the first plastic film is electrostatically charged. If the first plastic film and the side of the substrate facing the first plastic film are made of different plastics, the plastic with the higher dielectric constant is preferably electrostatically charged.It is also conceivable that both the substrate and the first plastic film become electrostatically charged, with the substrate and the first plastic film then having, for example, an opposite electrical potential difference. This electrostatic charging can occur, for instance, through the action of non-electrically conductive deflection rollers, pressure rollers, or rollers in general on the film web or a plastic coating of the substrate.

[0017] The advantages of corona treatment are similar to those of electrostatic charging; here, too, the glass plate effect promotes adhesion between the smooth surfaces of the substrate and the first plastic film. The substrate (for example, in multilayer substrates, the layer facing the first plastic film), the first plastic film, or both can be corona-treated. In corona treatment, a film web or a plastic-coated, web-shaped substrate is exposed to a high-voltage electrical discharge, for example, between a grounded, polished steel or aluminum roller and a closely fitting insulated electrode, or between an insulated roller and an uninsulated electrode. The film web or coated substrate rests on the polished roller, and only the side of the film web facing the electrode is discharged.The coated substrate is treated. The electrode is typically supplied by a high-frequency generator with an alternating voltage of 10 to 20 kV and a frequency between 10 and 60 kHz.

[0018] It is also conceivable that the substrate and / or the first plastic film undergo corona treatment first, followed by electrostatic charging of the substrate and / or the first plastic film. The prior corona treatment improves the subsequent electrostatic charging.

[0019] One advantage of the release liner, containing a UV-curing release layer, between the substrate and the first plastic film is that the first film can be made thinner—for example, thinner than with electrostatic charging or corona treatment—and the film material is then easier to handle during further processing. Another advantage is that the adhesive properties of the release liner can be precisely controlled by the chemical formulation of the UV-curing release layer, thus ensuring residue-free removal of the UV-curing release layer.

[0020] The application of at least one security feature can be done either directly onto the first plastic film or via one or more intermediate layers. Several security features, identical or different, can be arranged side by side or on top of each other.

[0021] "Optically detectable" means that an optical effect on the security feature is visible to the naked eye or with the use of an optical device, such as a filter. The optical effect can be a static color effect (caused, for example, by color printing in certain areas or by metallization in certain areas) or a variable color effect, an optically variable effect such as a color shift (where the color changes with the viewing angle), effects produced by embossed structures such as holograms, moving images, and / or optically achromatic embossed structures.

[0022] "Machine readable" means that an effect on the security feature can be read using technical aids, such as a magnetic effect through magnetic particles, or an optical effect in the infrared or UV range.

[0023] To protect the security feature, a second, sheet-like plastic film or a protective coating is applied to it—either directly or via one or more intermediate layers. The second plastic film can be the same width as the first plastic film and / or the substrate. The protective coating is typically applied either across the entire area defined by the first plastic film or only to parts of it. The protective coating can consist of one or more partial layers, i.e., multiple layers stacked on top of each other and / or different layers placed side by side. The second plastic film is then bonded to the security feature using adhesive.The protective coating can be applied directly to the security feature (at least one) and, if necessary, to intermediate layers such as further security features. A second plastic film is advantageous when the film patch is applied over an opening, so that the second plastic film lies over the opening. In this case, this second plastic film is preferably transparent so that the security feature can be seen through the opening. The second plastic film is preferably the same as the first, i.e., made of the same material, especially the same polymer, and with the same thickness. This has the advantage that the final film patch does not tend to curl up due to differing material properties of the first and second plastic films.For valuable or security documents without perforations, the second plastic film can be replaced by a protective varnish layer because this side of the finished foil patch is not exposed, but rather attached to a polymer banknote substrate or plastic card material. Preferred protective varnishes include those based on nitrocellulose, acrylates and their copolymers, polyamides and their copolymers, polyvinyl chlorides and their copolymers, crosslinking varnishes, solvent-based varnishes, waterborne varnishes, or UV-curing varnishes.

[0024] The heat-activated adhesive layer, applied to the second plastic film or the protective lacquer layer, can be a heat-seal adhesive, a heat-seal lacquer, or a hot melt adhesive. This adhesive layer serves to attach the finished foil patch to the security or valuable document, particularly through the application of heat, and is specifically formulated for the material of the security or valuable document. The adhesive can be applied across the entire surface or only partially, for example, in a grid pattern or adapted to the shape of the finished foil patch.

[0025] The foil material produced in this way offers a high level of counterfeit protection due to the integrated security feature. It can securely seal windows in banknotes or other security and valuable documents because the first plastic film provides sufficient stability. Since the first plastic film of the foil patch, when attached to a security or valuable document, is positioned away from the document, it protects the security feature from external influences and increases the durability of the foil patch, thus improving the circulation of banknotes.

[0026] The film material according to the invention is present as a web due to the web-shaped carrier substrate and can be processed on commercially available application equipment by die-cutting film patches that remain on the web-shaped carrier substrate and are then applied from this web either directly to a security or valuable document, or, for example in the case of banknotes, to a substrate for security or valuable documents – preferably in webs or sheets. The individual security or valuable documents, such as banknotes, are then subsequently cut or die-cut from this substrate.

[0027] In one embodiment of the invention, the first plastic film is provided in web form and is bonded to the substrate using a roll-to-roll process. In this way, the first plastic film can be easily bonded to the substrate using commercially available machinery, such as a laminating machine.

[0028] In one embodiment of the invention, when bonding the first plastic film to the substrate by means of prior electrostatic charging or corona treatment, a heated laminating system is used which heats the substrate and the first plastic film from one or both sides. This increases the initial adhesion and compensates for any deformations of the substrate or the first plastic film. If a PE-coated substrate is used, a hot melt coating station (HMCS) can also be used.

[0029] In an alternative embodiment of the invention, when applying a first plastic film to a web-shaped carrier substrate by means of a release agent coating containing a UV-curing release layer, it is provided that either the UV-curing release layer is applied to the carrier substrate or to the first plastic film, a laminating adhesive layer is applied to this release layer, and subsequently the carrier substrate and the first plastic film are bonded together by a laminating process. The release layer is non-adhesive, meaning that it adheres to a non-adhesive layer, such as paper or a plastic film, but can be separated from the adjacent paper or plastic layer without leaving any residue. The UV-curing release layer is cured by UV irradiation.The adhesive properties of the UV-curing release layer can be specifically tailored through its chemical formulation. In this case, for example, the UV-curing release layer would be applied to the first plastic film, cured with UV light, coated with a laminating adhesive layer, and the laminating adhesive layer bonded to the substrate. This would then allow the substrate, along with the laminating adhesive layer and the UV-cured release layer, to be separated from the first plastic film without leaving any residue. Alternatively, the UV-curing release layer could be applied to the substrate, cured with UV light, coated with a laminating adhesive layer, and the laminating adhesive layer bonded to the first plastic film.This allows the carrier substrate to be separated from the UV-crosslinked release layer later, while the laminating adhesive layer and the UV-crosslinked release layer remain on the first plastic film.

[0030] A UV-curing embossing varnish, which is also used for embossing structures, can be used as a UV-curing release layer.

[0031] According to one embodiment of the invention, when applying the at least one security feature, precisely such an embossed structure is produced by first applying a UV-curing embossing lacquer to the first plastic film, embossing it, and then curing it with UV light. Embossed structures made of UV-curing embossing lacquer are thermally and mechanically more stable than hot-embossed structures. Furthermore, structures made of UV-curing embossing lacquer with a high aspect ratio are often more faithfully molded than hot-embossed structures.

[0032] After the application of an optically effective layer, the embossed structure, together with this layer, forms an optically variable security feature, such as a hologram, a kinegram, a lens array, micromirrors, achromatic structures, or color-reflecting structures. Several identical or several different security features can be produced side-by-side (in the plane of the first plastic film) using the embossed structure. One or more embossed structures can be applied only to partial areas of the first plastic film, which will later form the entire surface area of ​​a film patch or only a portion thereof. Multiple identical embossed structures can also be applied at regular intervals, which will later, for example by die-cutting, each belong to a specific film patch. In principle, the embossed structure can also be applied across the entire surface of the first plastic film.

[0033] The optically active layer is typically applied directly to the embossed structure, either partially or across the entire surface. This layer can be reflective, absorbent, or refractive. It can consist of several sublayers that overlap completely or partially. It is preferably applied to the embossed structure using vacuum deposition (PVD) processes such as metallization, electron beam evaporation, or sputtering. Depending on the optical properties and desired effect, the layers, particularly those deposited by vapor deposition, are transparent, partially transparent, translucent to opaque, or completely opaque. The optically active layer—either as a whole or only one or more of its sublayers—can be structured using known demetallization, washing, laser, and / or etching processes, for example, to create security features visible in transmitted light in the form of cutouts.The cutouts can be arranged with precise registration to the embossed structures and complement them, for example to create a common motif. However, the cutouts can also overlay the embossed structures.

[0034] The visually detectable security feature can generally be visible in reflected and / or transmitted light. The security feature with embossed lacquer structure and optically effective layer can be visible in reflected light when viewed from the side of the optically effective layer. It can also be detectable in transmitted light, which first passes through the embossed structure and then through the optically effective layer into the eye of the viewer located on the side of the optically effective layer.

[0035] Additional security features can be incorporated onto, beneath, or between sub-layers of the optically effective layer, either across the entire surface or only in specific areas. Examples include UV, fluorescent, and infrared security features. These additional security features can produce optical effects, particularly those visible to the human eye, or machine-readable effects. The additional security features can also be optically variable, such as a color-shifting coating, e.g., based on thin-film elements, liquid crystals, thin-film pigments, or liquid crystal pigments.Other security features can also include partially applied translucent layers, printed colored layers, printed metallic layers, each without an optically variable effect, or fluorescent layers.

[0036] The inventive method advantageously comprises the following steps after the application of the adhesive layer to the second plastic film or to the protective lacquer layer: Punching out at least one foil patch from the side of the adhesive layer to at least through the first plastic film, but preferably not through the substrate, removing the foil web punched out outside the at least one foil patch from the substrate.

[0037] In this way, the foil patches can be produced on standard die-cutting machines, such as those used for high-quality jewelry labels or overlay foils. If the backing substrate is not die-cut, it can continue to serve as a web-like backing until the foil patches are applied to a security or valuable document, which facilitates feeding the foil patches to the documents. The die-cut foil web is typically wound up, and during winding, the excess material outside the die-cut area, i.e., outside the foil patches, is removed ("weeded") in the form of a die-cut grid and wound up separately. If the first plastic film is bonded to the backing substrate by means of a release agent, the die-cutting can extend to or even into the release agent.This would prevent the carrier material from being punched out and allow it to continue serving as a web-shaped carrier substrate.

[0038] The foil patches can have any shape, such as circular, oval, triangular, quadrilateral, polygonal, or star-shaped. The die-cutting can, but does not have to, be precisely aligned with the embossing patterns, meaning that identical foil patches with the same embossing patterns are created at the same positions within the contour of each individual foil patch.

[0039] The carrier substrate can be cut into individual strips, on which preferably only one foil patch is arranged in the width direction, but many identical foil patches are arranged one behind the other in a line in the length direction. The foil patches are placed on the security or valuable document with the adhesive side facing up and attached to the document, such as security paper for banknotes, for example, by heat transfer and activation of the adhesive layer. In the case of heat transfer, the heat can be supplied through the carrier substrate and / or through the security or valuable document. Simultaneously with the heat supply, the foil patch is pressed down. After the foil patches have been applied to the target substrate, the carrier substrate can be removed and, if necessary, reused.

[0040] The foil patch is preferably applied over a window area of ​​the target substrate, i.e., the security or valuable document or the source material (e.g., sheets, rolls) for security or valuable documents. As mentioned earlier, the window can either be an opening in the material of the security or valuable document, which is closed by the foil patch, or the window can be a transparent area in the material of the security or valuable document onto which the foil patch is applied.

[0041] The invention also includes a film material that can be produced by the inventive method.

[0042] The invention also includes a safety element in the form of a foil patch, which can be produced from a foil material manufactured by the inventive method.

[0043] The invention also includes a security or valuable document that incorporates a security element according to the invention in the form of foil patches. This element can preferably be applied as a closure over window-shaped openings in banknotes and documents. It contains at least one security feature and can also include further security features, as already explained above. In particular, these security features can be optically active structures, optically variable elements, partial metal layers with cutouts in the form of characters, patterns and images, luminescent elements and images. The security features can be visible in reflected light as well as transmitted light in the window area of ​​the banknote or document. BRIEF DESCRIPTION OF THE FIGURES

[0044] The invention will now be explained in more detail with reference to schematic figures illustrating exemplary embodiments of the inventive method, the film material produced therewith, and the film patches produced from the film material, the latter also in the state where they are affixed to security or valuable documents. This shows Fig. 1 shows a longitudinal section through a film material in a first embodiment, wherein the first plastic film is bonded to the substrate by means of prior electrostatic charging or corona treatment; Fig. 2 shows a longitudinal section through the film material made of Fig. 1 with die-cut foil patches, Fig. 3 a longitudinal section through the weeded foil material made of Fig. 2 , Fig. 4 a longitudinal section through a foil patch made of Fig. 3 , applied to a security or valuable document, Fig. 5 a longitudinal section through a film material in a second embodiment, wherein the first plastic film is bonded to the carrier substrate by means of a releaseable coating, Fig. 6 a longitudinal section through a film patch made of Fig. 5 , applied to a security or valuable document. WAYS TO IMPLEMENT THE INVENTION

[0045] Fig. 1 This shows how a film material for security elements in the form of film patches 4 can be manufactured and constructed in a first embodiment. First, a first plastic film 1, which is also web-shaped, is applied to a web-shaped carrier substrate 3, preferably using a roll-to-roll process. Prior to this, either the first plastic film 1, or the carrier substrate 3, or both are subjected to corona treatment or electrostatic charging. The two web-shaped materials are then pressed together by means of rollers and adhere to each other. This pressing together can take place in a heated laminating machine, which can additionally heat the carrier substrate 3 and the first plastic film 1 from one or both sides to improve adhesion and equalize stresses between the two materials.The carrier substrate can then later be separated from the first plastic film 1, as indicated by the horizontal dashed lines.

[0046] At least one security feature 7, which is optically detectable and / or machine-readable, is then applied to the free side of the first plastic film 1. This can be, for example, an embossed structure, where a UV-curing embossing varnish is first applied to the first plastic film 1, embossed, and then cured with UV light, and where, as a rule, an optically effective layer is applied directly to the embossed structure. The optically effective layer can be a reflective, absorbing, or refractive layer. It can consist of several sublayers that overlap completely or partially. In this way, holograms, kinegrams, microlens arrangements, micromirrors, other achromatic structures, or color-reflecting structures, especially with a color-shifting effect, can be formed.

[0047] To protect the safety element 7 from external influences, a second, sheet-like plastic film 2 is applied over it. A laminating varnish 8 is applied to the safety element 7, acting as an adhesive for the second plastic film 2 and thus permanently bonding it to the existing layered composite. To protect the film patches 4 subsequently produced from the film material (see Fig. 2-4 ) on a security or value document 11 (see Fig. 4 To enable permanent attachment, an adhesive layer 10 is applied to the second plastic film 2 – here covering the entire surface. The adhesive layer 10 can be activated by heat.

[0048] It would also be conceivable to first apply at least one security element 7, or parts thereof, to the first plastic film 1 and only then bond it to the carrier film 3 as described. It would also be conceivable to apply further layers to at least one security element 7 – for example, the laminating lacquer 8, the second plastic film 2, and the adhesive layer 10 – before bonding the first plastic film 1 to the carrier film 3 as described above.

[0049] In Fig. 2 is shown how the foil material is made from Fig. 1 Individual foil patches 4 are produced. A die-cutting tool, represented by thick vertical lines, cuts through the foil material from the side of the adhesive layer 10 down to the carrier substrate 3, creating individual foil patches 4 consisting of congruent sections of the first plastic film 1, the security feature 7, the laminating varnish 8, the second plastic film 2, and the adhesive layer 10. The adhesive layer 10 does not need to be continuous but could also be smaller in area than the sections of the first or the second plastic film 1, 2. Similarly, the security feature 7 does not need to extend over the entire cross-section of the foil patch 4; if necessary, the two adjacent layers, here the first plastic film 1 and the laminating varnish 8, would then touch in some areas.

[0050] As in Fig. 3 As shown, the excess material outside the die-cut, i.e., outside the film patches 4, can be removed ("weeded") in the form of a die-cut grid and wound up separately. Individual film patches 4 then remain on the carrier substrate 3, usually also arranged in a grid in two dimensions. The carrier substrate 3 can then be cut into strips (see thick vertical line), on which strips preferably only one film patch 4 is arranged in the width direction, but many identical film patches are arranged one behind the other in a line in the length direction.

[0051] The strips can be rolled up and then unrolled to apply the foil patches 4 to a security or valuable document 11 and adhered with the adhesive layer 10, for example over a window of the security or valuable document 11, see

[0052] Fig. 4 For this purpose, a heated stamp can then be applied to the side of the security or valuable document 11 and / or to the side of the carrier substrate 3. This activates the adhesive layer 10 and permanently bonds it to the surface of the security or valuable document 11. Once this has occurred, the carrier substrate can be peeled off the first plastic film 1, as indicated by the arrow. This film then protects the security feature from below, while the security feature is protected from above by the second plastic film 2.

[0053] Fig. 5 This shows how a film material for security elements in the form of film patches 4 can be manufactured and constructed in a second embodiment. First, a first plastic film 1, which is also in a web shape, is applied to a web-shaped carrier substrate 3, preferably using a roll-to-roll process. For this purpose, the carrier substrate 3 is first provided with a release agent containing a UV-curing release layer 5: A UV-curing release layer 5 is applied to the first plastic film 1, cured with UV light, and then a laminating adhesive layer 6 is applied to the UV-cured release layer 5. Subsequently, the carrier substrate 3 and the first plastic film 1 are bonded together by means of a laminating process, i.e., essentially pressed together by rollers.The laminating adhesive layer 6 forms a permanent bond with both the UV-crosslinked release layer 5 and the other adjacent layer, here the substrate 3. The UV-crosslinked release layer 5, with its side opposite the laminating adhesive layer 6, only forms a detachable bond and can later be separated from the first plastic film 1 together with the substrate 3 and the laminating adhesive layer 6, as is again shown by the dashed lines.

[0054] Alternatively, a UV-curing release layer 5 could first be applied to the substrate 3, cured with UV light, and then a laminating adhesive layer 6 applied to the UV-cured release layer 5. Subsequently, the substrate 3 and the first plastic film 1 are bonded together using a laminating process, essentially by pressing them together with rollers. The laminating adhesive layer 6 forms a permanent bond with both the UV-cured release layer 5 and the other adjacent layer, namely the plastic film 1. The side of the UV-cured release layer 5 facing the laminating adhesive layer 6 forms only a detachable bond, allowing the substrate 3 to be later separated from the laminating adhesive layer 6 and thus from the remaining layered assembly containing the first plastic film 1.

[0055] In both cases, at least one security feature 7, which is optically detectable and / or machine-readable, is applied to the free side of the first plastic film 1. This can, for example, again be an embossed structure, where a UV-curing embossing varnish is first applied to the first plastic film 1, this is embossed, and then cured with UV light, and where, as a rule, an optically effective layer is applied directly to the embossed structure. The optically effective layer can be a reflective, absorbing, or refractive layer. It can consist of several sublayers that overlap completely or partially. In this way, holograms, kinegrams, microlens arrangements, micromirrors, other achromatic structures, or color-reflecting structures, especially with a color-shifting effect, can be formed.

[0056] To protect the security element 7 from external influences, a protective lacquer layer 9 is applied over the security element 7, covering the entire cross-section of the film material. To attach the film patches 4 subsequently produced from the film material to a security or valuable document 11 (see Fig. 6 To ensure permanent attachment, an adhesive layer 10 is applied to the protective lacquer layer 9 – here covering the entire surface. The adhesive layer 10 can be activated by heat.

[0057] It would also be conceivable to first apply at least one safety element 7 to the first plastic film 1 and only then bond it to the carrier film 3 as described. It would also be conceivable to apply further layers to at least one safety element 7 – such as the protective lacquer layer 9 or the adhesive layer 10 – before bonding the first plastic film 1 to the carrier film 3 as described above.

[0058] The protective coating layer 9 does not need to be applied across the entire cross-section of the film material, but can also be applied only partially, in specific areas. Accordingly, the adhesive layer 10 could then be applied partially to the protective coating layer 9 and partially to the safety element 7, or only to the (partially present) protective coating layer 9, or only to the safety element 7.

[0059] In Fig. 5 The figure also shows how individual film patches 4 are produced from the film material. A die-cutting tool, represented by thick vertical lines, cuts through the film material from the side of the adhesive layer 10 at least as far as the UV-curing release layer 5, creating individual film patches 4 consisting of congruent sections of the first plastic film 1, the security feature 7, the protective lacquer layer 9, and the adhesive layer 10. The film material could also be cut through as far as the laminating adhesive layer 6, or as far as the carrier substrate 3. The adhesive layer 10 need not be continuous, but could also be smaller in area than the sections of the first plastic film 1.

[0060] Analogous to in Fig. 3 As shown, the excess material outside the die-cut, i.e., outside the foil patches 4, can be removed ("weeded") in the form of a die-cut grid and wound up separately. Individual foil patches 4 then remain on the carrier substrate 3, usually also arranged in a grid-like pattern in two dimensions. The carrier substrate 3 can then be cut into strips, on which strips preferably only one foil patch 4 is arranged in the width direction, but many identical foil patches are arranged one behind the other in a line in the length direction. The strips can be rolled up and then unwound to apply the foil patches 4 to a security or valuable document 11 and adhered to it with the adhesive layer 10, for example, see [reference]. Fig. 6 For this purpose, a heated stamp can be applied from the side of the security or valuable document 11 and / or from the side of the carrier substrate 3, which activates the adhesive layer 10 and permanently bonds it to the surface of the security or valuable document 11. Once this has occurred, the carrier substrate can be peeled off the first plastic film 1, as indicated by the arrow. This film then protects the security feature from below, while the security feature is protected from above by the security or valuable document 11 and by the protective lacquer layer 9.

[0061] Basically, the layers above at least one security feature 7 in the version of the Fig. 1-4 with those in the version of the Fig. 5-6 Interchangeable. It could therefore be in the Fig. 1-4 Instead of the laminating lacquer 8 and the second plastic film 2, a protective lacquer layer 9 – partial or full-surface – could be applied, or it could be in the Fig. 5-6 Instead of the protective lacquer layer 9, a laminating lacquer 8 and a second plastic film 2 are applied. REFERENCE MARK LIST

[0062] 1 First plastic film 2 Second plastic film 3 Carrier substrate 4 Film patch 5 UV-curing release layer (separable coating) 6 Laminating adhesive layer (separable coating) 7 Security feature 8 Laminating varnish 9 Protective varnish layer 10 Adhesive layer 11 Security or valuable document

Claims

1. Method for producing film material for security elements in the form of film patches (4), comprising the following steps to be carried out in the order stated: - Applying a first plastic film (1) in web form to a web-shaped carrier substrate (3), wherein the first plastic film (1) is bonded to the carrier substrate (3) by means of prior electrostatic charging, prior corona treatment or by means of a release coating containing a UV-crosslinking release layer (5), - Applying at least one security feature (7) that is optically detectable and / or machine-readable to the first plastic film (1), - Applying a second plastic film (2) in web form or a protective lacquer layer (9) to the at least one security feature (7), - Applying an adhesive layer (10), in particular heat-activated, to the second plastic film (2) or to the protective lacquer layer (9).

2. Method according to claim 1, characterized by the fact that the first plastic film (1) is joined to the carrier substrate (3) using a roll-to-roll process.

3. Method according to claim 1 or 2, characterized by the fact that When joining the first plastic film (1) to the carrier substrate (3) by means of prior electrostatic charging or prior corona treatment, a heated laminating system is used which heats the carrier substrate (3) and the first plastic film (1) from one side or from both sides.

4. Method according to claim 1 or 2, characterized by the fact thatTo apply a first plastic film (1) to a web-shaped carrier substrate (3) by means of a releaseable coating, a UV-crosslinking release layer (5) is applied either to the carrier substrate (3) or to the first plastic film (1), a laminating adhesive layer (6) is applied to this, and then the carrier substrate (3) and the first plastic film (1) are joined together by means of a laminating process.

5. Method according to any one of the preceding claims, characterized by the fact that the first plastic film (1) is a PET film with a thickness of 3 µm to 15 µm, preferably of 6 µm to 8 µm.

6. Method according to any one of the preceding claims, characterized by the fact that When applying at least one security feature (7), an embossing structure is produced by first applying a UV-crosslinking embossing varnish to the first plastic film (1), embossing it and then curing it with UV light.

7. Method according to any of the preceding claims, characterized by the fact that the second plastic film (2) is transparent.

8. Method according to any one of the preceding claims, characterized by the fact that the second plastic film (2) is the same as the first plastic film.

9. Method according to any one of the preceding claims, characterized by the fact that The process, after applying the adhesive layer (10) to the second plastic film (2) or to the protective lacquer layer (9), comprises the following steps: - punching out at least one film patch (4) from the side of the adhesive layer (10) at least through the first plastic film (1), but preferably not through the carrier substrate (3), - removing the film web punched out outside the at least one film patch (4) from the carrier substrate (3).

10. Foil material for security elements in the form of foil patches, producible according to a method according to any one of claims 1 to 9, characterized by the fact thatit comprises the following layers in the specified order: - a web-shaped carrier substrate (3), - a first plastic film (1) which is web-shaped and adheres to the carrier substrate (3) either without an intermediate layer or via a separable coating containing a UV-crosslinking release layer (5), - at least one security feature (7) applied to the first plastic film (1) which is optically detectable and / or machine-readable, - a second plastic film (2) which is web-shaped, or a protective lacquer layer (9) applied to the at least one security feature (7), - an adhesive layer (10), in particular heat-activated, which is applied to the second plastic film (2) or to the protective lacquer layer (9).

11. Security element in the form of a foil patch (4), producible according to a method according to claim 10, characterized by the fact thatit comprises the following layers in the specified order: - a first plastic film (1), - at least one security feature (7) applied to the first plastic film (1) which is optically detectable and / or machine readable, - a second plastic film (2) or a protective lacquer layer (9) applied to the security feature (7), - an adhesive layer (10), in particular heat-activated, applied to the second plastic film (2) or to the protective lacquer layer (9).

12. Security or valuable document (11) comprising a security element according to claim 11, wherein the security element is in the form of a foil patch (4) with the adhesive layer (10) attached to the security or valuable document (11).

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