LAMINATE AND METHOD FOR MANUFACTURING LAMINATE

Abstract

The present invention relates to a laminate (1) comprising a security element (20) laminated between a recording layer (11) and a cover layer (12) and a method for manufacturing the laminate (1), wherein an adhesive layer (25) adheres to the recording layer (11) and a release layer (21) adheres to the cover layer (12), or wherein the adhesive layer (25) adheres to the cover layer (12) and the release layer (21) adheres to the recording layer (11), and the laminate (1) is designed such that the adhesive layer (25) of the security element (20) can be divided by tensile forces exerted on the security element (20) by the recording layer (11) and the cover layer (12).

Description

[Technical field]

[0001] The present invention relates to a laminate and a method for producing the laminate. [Background technology]

[0002] It is known to encapsulate a security element in a laminate, such as a security document, between two layers that are joined to one another by means of a material adhesive bond, so that the security element is completely encapsulated by these two layers of the security document. A material adhesive bond achieves high adhesion forces and protects the security element from damage and manipulation. However, due to different material properties of the layers of the security element and the adjacent layers of the security document, interfaces with different adhesion forces, in particular reduced adhesion forces, are formed at the interface of the security element. If the security element has different adhesion forces at its interface from the layers to which it is joined by means of a material bonding method, counterfeiters can take advantage of this by removing the security element by targeted peeling or peeling of the layers of the security document or by adding false information to the security document and resealing it. Summary of the Invention

[0003] It is therefore an object of the present invention to identify a laminate, in particular a security document, which has improved protection against manipulation and counterfeiting, and to identify a method for producing same.

[0004] This object is achieved by a laminate, in particular a security document, according to claim 1. The laminate, in particular a security document, comprises a recording layer, a transparent cover layer and a security element laminated between the recording layer and the cover layer. The security element has a release layer, a replication layer with a relief surface arranged on the side opposite the release layer, a reflective layer arranged on the relief surface and an adhesive layer. The adhesive layer forms the side of the security element opposite the release layer, a) The adhesive layer adheres to the recording layer and the release layer adheres to the cover layer, or the adhesive layer adheres to the cover layer and the release layer adheres to the recording layer. In addition, b) The laminate is designed in such a way that the adhesive layer of the security element can be split by the tensile forces exerted on the security element by the recording layer and the cover layer.

[0005] This object is further achieved by a method according to claim 31. In a method for producing a laminate, in particular a security document, preferably according to one of claims 1 to 30, the following steps are carried out, in particular in the given sequence: - providing a recording layer; - providing a transparent cover layer; - preparing a security element, in particular a laminate according to the invention, preferably a security element as defined in one of claims 1 to 30, the security element having a release layer, a replication layer with a relief surface arranged on the side opposite the release layer, a reflective layer arranged on the relief surface and an adhesive layer forming the side of the security element opposite the release layer, the security element being or being adhered by the adhesive layer to a cover layer or to a recording layer, - laminating a security element between the recording layer and the cover layer, so that a) the adhesive layer adheres to the recording layer and the release layer adheres to the cover layer, or the adhesive layer adheres to the cover layer and the release layer adheres to the recording layer; b) The adhesive layer of the security element can be divided by the tensile forces exerted on the security element by the recording layer and the cover layer.

[0006] The adhesive layer of the laminate according to the invention and of the laminate obtainable by the method according to the invention can be split by cohesive failure, in particular by the tensile forces exerted on the security element by the recording layer and the cover layer. The presence of an adhesive layer that can be split in the sense of the invention can be confirmed in particular by the peel test described below. Cohesive failure is in particular the failure of the bond of the adhesive itself, preferably when the adhesive strength of the adhesive on the material surface is greater than the internal strength of the adhesive. In the case of cohesive failure in the adhesive layer, in particular a separation of the adhesive layer into two partial layers occurs, in which the partial layers of the adhesive layer separated from each other in each case continue to adhere to the directly adjacent layer adjacent to the adhesive layer. In particular, the two partial layers are continuous layers that are separated or are separated from each other by cohesive failure in each case, preferably there is a pure cohesive failure. During cohesive failure, the tip of the propagating crack may briefly hit the interface of the layer adjacent to the adhesive layer, but does not propagate along it if the separation is progressing, for example so that after the separation the adhesive layer is in each case in the form of a completely discontinuous partial layer and / or so that after the separation the adhesive layer is in each case in the form of a predominantly continuous partial layer. On the other hand, in the case of adhesion failure, the adhesive layer loosens, particularly at the interface with one or more layers that are directly adjacent to the adhesive layer and are adjacent to the adhesive layer, and in particular the adhesion failure results in the adhesive layer peeling off continuously or mainly continuously from the interface.

[0007] Due to the presence of a splittable adhesive layer, when the cover layer is peeled off, the adhesive layer is split, so that a part or partial layer of the adhesive layer is also peeled off, in particular due to cohesive failure of the adhesive layer, which results in a reduction in the layer thickness of the security element and a plastic deformation of the adhesive layer persists, in particular on the surface of the security element, making the undetectable peeling or reuse of the security element as a whole more difficult. In this way, the manipulation attempt is advantageously more easily detectable, or the detectability can only be reduced by further efforts. Furthermore, studies have shown that the increased peeling force, also called peeling force, which is necessary when trying to peel off the cover layer or the recording layer from the security element, can be achieved via a splittable adhesive layer or by a corresponding predetermined breaking point defined by the adhesive layer. Peeling off the laminate and the non-destructive reuse of the security element is therefore made more difficult by the general adhesive force conditions. It is therefore possible further to achieve particularly high adhesion forces both at the interface of the adhesive layer and at the interface of the release layer with the adjacent recording layer or with the adjacent cover layer, whereby in particular the difference in adhesion forces at the two interfaces of the adhesive layer can be adapted and in particular reduced so that continuous peeling of the layers of the security document, which is easy to control, becomes more difficult.

[0008] In particular, the laminate according to the invention is produced by the method according to the invention. The method according to the invention is therefore preferably carried out in order to obtain the laminate according to the invention.

[0009] Advantageous designs of the invention are set forth in the dependent claims.

[0010] By "adhesion" it is preferably meant direct bonding. The adhesive layer is preferably directly adhered to the recording layer, with the release layer directly adhering to the cover layer, or the adhesive layer is directly adhered to the cover layer and the release layer is directly adhered to the recording layer. In particular, the adhesive force of the two layers adhering to each other is at a value of 1 N / 10 mm strip width or more, preferably 1.5 N / 10 mm strip width or more, more preferably 3.5 N / 10 mm strip width or more, measured according to standard ISO / IEC 10373-1:2006(E); paragraph 5.3 and / or the peel test described below. In a further embodiment, an intermediate layer can be arranged between the adhesive layer and the recording layer.

[0011] By layer is meant in particular a substantially two-dimensional structure. The layer itself is preferably monolayer or multilayer.

[0012] Laminate means, in particular, a multi-layer structure in which at least two layers are joined together by a material bonding method, in particular welded. For example, the laminate is produced or has been produced by a lamination method. The lamination method can be carried out as further described below. Laminated or laminating means that the material-adhesive bond, in particular between the recording layer and the cover layer, is produced or has been produced, preferably by a lamination method, preferably with the result that the security element is completely surrounded by the two layers. The security element is laminated or is laminated, in particular by welding the recording layer and the cover layer, preferably in such a way that it completely surrounds the security element.

[0013] Planar or main surface preferably means the surface which the laminate or the security element or one of the layers of the laminate and / or security element extends over, disregarding its thickness.

[0014] By "transparent" it is preferably meant a transmittance of 90% or more, in particular a transmittance of wavelengths in the range of 380 nm to 780 nm, preferably in the range of wavelengths visible to the human eye.

[0015] By "semi-transparent" it is preferably meant a transmittance in the range of 30% to 90%, in particular a transmittance for wavelengths in the range of 380 nm to 780 nm, preferably in the wavelength range visible to the human eye.

[0016] By "opaque" it is preferably meant a transmittance of less than 30%. Transmittance preferably means the ratio between the amount of light that is irradiated and / or incident on the medium and the amount of light that appears on the opposite side of the medium, in particular without any change in the frequency or wavelength of the light. The light that is not transmitted is preferably reflected, scattered and / or absorbed by the medium. Thus, for example, if the medium has a transmittance of 0.9 or 90%, then 90% of the irradiated light is perceptible on the opposite side of the medium.

[0017] When considering the transmittance of a layer, reflections, in particular at the interfaces of this layer, are not taken into account.

[0018] It is possible for the security element to provide optically varying effects. The optically varying effects can be selected, individually or in combination, from in particular a color change depending on the angle of view, a contrast change depending on the angle of view, a motif change depending on the angle of view, a holographic representation, a cinematographic representation. The angle of view of the security element can be changed in particular by tilting, turning and / or bending by the observer. The security element is preferably formed or formed as a transfer layer of a transfer film. One or more security elements are or can be laminated to the security document having an adhesive layer adhering to the recording layer and a release layer adhering to the cover layer, and one or more further security elements are or can be laminated to the security document having an adhesive layer adhering to the cover layer and a release layer adhering to the recording layer.

[0019] The recording layer and / or the cover layer preferably comprise or consist of polycarbonate. It is particularly advantageous if the recording layer and the cover layer comprise or consist of polycarbonate and are bonded or are bonded to one another in a material-bonding manner, in particular by lamination, in particular by welding. A particularly stable bond is achieved by lamination. The cover layer preferably has a layer thickness in the range of 25 μm to 250 μm and / or the layer thickness of the cover layer relative to the layer thickness of the adhesive layer is in the range of 1.25 to 250 and / or the sum of the thickness of the adhesive layer and the thickness of the cover layer is in the range of 26 μm to 270 μm.

[0020] In addition to polycarbonate, for example the cover layer and / or the recording layer may contain in particular dyes, in particular coloured pigments and / or effect paints, for example optically variable pigments (OVI) and / or metallic pigments.

[0021] The recording layer preferably has a thickness in the range of 25 μm to 250 μm. The recording layer is in particular laser processable or laser processable. The recording layer preferably comprises further substances, in particular doping. The energy absorption capacity of the recording layer can be improved by doping. Substances for doping are in particular selected from one or more of chromium, erbium, neodymium, praseodymium, titanium, ytterbium. In this way, items of information are inscribed or are inscribed in the recording layer, for example by means of a laser, preferably a YAG laser, preferably a Nd:YAG laser (neodymium-doped yttrium-aluminum-garnet laser). The oscillation wavelength of the YAG laser is preferably 1064 nm. The cover layer is preferably transparent to the wavelength of 1064 nm and / or to the wavelength of the laser. In this way, the recording layer is laser processable, in particular through the cover layer, and items of information can be inscribed in the recording layer. The security element preferably overlaps such inscribed information items and thus enhances the protection against counterfeiting of the laminate, in particular the security document.

[0022] The adhesive layer can be bonded to the cover layer or the recording layer via a material-bonding, in particular an adhesive joint. The release layer is preferably bonded to the cover layer or the recording layer via a welded joint, in particular without an intermediate adhesive joint. In particular, the cover layer and the recording layer, preferably the release layer, form a monolithic body. The bonding of the security element with the adhesive layer and the release layer is therefore preferably based on different physical principles, whereby the peeling of the security element on the release layer side is preferably very complicated to impossible. The adhesive layer is preferably bonded to the reflective layer via a material-bonding joint and / or to the replication layer via a material-bonding joint. The reflective layer is bonded in particular to the replication layer via a material bond.

[0023] The material bond between the recording layer and the cover layer is, for example, a polycarbonate layer, in particular consisting of almost 100% polycarbonate, and is advantageously achieved by welding in a lamination process. For example, the separation of the layers cannot be easily achieved by applying tensile forces to the interface. However, the security element laminated thereto acts in particular as a foreign body in the structure. That is to say, the adhesion between the adjacent cover layer and the recording layer, in particular the adjacent polycarbonate layer, is significantly reduced compared to the direct adhesion between the cover layer and the recording layer. To extract the security element from the laminate, a counterfeiter can make an incision in the polycarbonate layer before tearing at the edge of the security element and then try to peel off one of the layers. This procedure is reproduced in the following test, and can be made even more difficult by increasing the predetermined breaking point provided by the adhesive layer for cohesive failure, and preferably by the selected shape and material parameters, for example the peel force.

[0024] The measurement of the peel force can be preferably carried out by a peel test of the laminate, as described below. The peel force is also called peel strength, peel force, peeling force or adhesion. The peel force can be measured in particular by a peel test according to ISO / IEC 10373-1:2006(E); paragraph 5.3 and / or by the peel test described below.

[0025] For the peel test, the optionally preconditioned laminate is cut into test pieces, preferably in the form of a card, in particular 10 mm wide.

[0026] For example, one or all layers of the security element are peeled off, for example the corresponding parts of the recording layer or the cover layer, preferably with a length of 5 mm to 10 mm. The upper layers of the security element, in particular the kinegram, are peeled off from the core, for example with a sharp knife. The peeling is only partial.

[0027] The peeled end, especially the cover layer, is preferably fixed to the holder of the tensile tester via a holding clamp or adhesive tape. Preferably, a right angle is formed between the peeled layer and the non-peeled layer fixed to the tensile tester. In particular, a right angle is formed between the cover layer and the recording layer. The bottom of the stack, especially the recording layer, is conveniently optionally fixed on a stabilizer.

[0028] During the tensile measurement, the peeled film layer can preferably be guided over a roller. The adhesion (peel strength) is preferably plotted on a graph and evaluated. The results are given, for example, in N / 10 mm.

[0029] It is also possible to carry out measurements in the absence of the security element, for example to measure the adhesion between the cover layer and the recording layer.

[0030] In particular, when the adhesive layer adheres to the recording layer, it has proven particularly advantageous to reduce the thickness of the adhesive layer in direct proportion to the thickness of the stabilizing layer which is preferably arranged between the adhesive layer and the replication layer, in particular to ensure cohesive failure.

[0031] Advantageously, there is or can be present in the laminate a peel force for peeling the cover layer from the security element that is equal to or greater than 3.5 N / 10 mm strip width.

[0032] The adhesive layer preferably serves to bond the transfer layer carrying one or more security elements according to the invention to the substrate during application, i.e. in particular when the security elements are applied to the cover layer or to the recording layer as substrate. It can be an adhesive layer that is activated by heat and pressure. Such adhesive layers that are activated by heat and pressure have in particular thermoplastic properties or are crosslinked by the action of heat, thereby preventing further activation by heat. It is also possible for such adhesive layers to have a thermoplastic part and a crosslinking component as a hybrid layer. For activation, a heated stamp is usually used, the shape of which defines the area to be transferred.

[0033] Alternatively, it can be transferred by so-called cold transfer. The adhesive layer is preferably printed onto the transfer layer of the transfer film or onto the cover layer or recording layer, which is then brought into contact with the transfer layer and the adhesive layer is cured, in particular forming a security element with the transfer layer and the printed adhesive layer. The curing is carried out in particular by UV irradiation. The adhesive layer can be composed of several different layers, and for example includes one or more adhesion promoter layers, in particular to ensure the bonding of the adhesive layer to the reflective layer or to the optionally present stabilizing layer.

[0034] The adhesion of the adhesive layer to the directly adjacent layers, which may be the cover layer or the recording layer, is advantageously higher than the cohesive strength of the adhesive layer. The adhesion within the adhesive layer, in particular the cohesive strength of the adhesive layer, is preferably lower than the adhesion between the security element and the recording layer and also lower than the adhesion between the security element and the cover layer.

[0035] In particular, it is advantageous if the adhesive layer has the lowest yield point, in particular the lowest upper yield point, and / or the lowest modulus of elasticity among the layers of the security element, the recording layer and / or the cover layer. The lowest cohesive and adhesive forces within the security element or within the laminate comprising the security element are preferably the cohesive forces of the adhesive layer.

[0036] It is also possible for the adhesive layer to comprise or consist of a ductile layer, by which is meant in particular the layer of the security element which has the highest elongation at break compared to the other layers of the security element.

[0037] The adhesive layer may have or consist of a ductile layer, which is a layer that can be divided by cohesive failure, which is advantageously promoted by the ductile layer or makes adhesive failure more difficult, especially in comparison with brittle adhesive layers, and in particular increases peel forces.

[0038] In particular, it is possible to design the laminate such that during the peel test and / or when attempting to peel the cover layer and / or the recording layer from the laminate, either a pure cohesive failure occurs or the adhesive layer peels off at one or more partial surfaces at the interface with the directly adjacent layer consisting of the cover layer or the recording layer. This can occur in particular in the case of partial adhesion failure. However, these partial surfaces preferably have a smaller surface area than the remaining surface of the interface that does not show peeling between the adhesive layer and the adjacent layer. The remaining surface of the interface in particular has a residue of the adhesive layer, since there is a cohesive failure. The laminate is preferably designed such that one or more partial surfaces occupy such a small surface area that the peel force measured in the peel test is at least 3.5 N / 10 mm. For this purpose, for example, the layer thickness of the adhesive layer can be adapted accordingly and / or an optionally present stabilizing layer can be used.

[0039] It is preferred that the residual surface covers at least 50%, at least 80%, preferably at least 90% of the surface area of ​​the interface, and / or that one or more sub-regions cover less than 50%, preferably less than 20%, preferably less than 10% of the surface area of ​​the interface.

[0040] Here, in particular, we look along a line perpendicular to the plane spanned by the interface. Overall, a high peel force is advantageously ensured even in the case of unevenness of the laminate, which can lead to local peaks of tensile stress and thus to local adhesion failure. In an advantageous embodiment, the adhesive layer, in particular the ductile layer, consists of a material having a modulus of elasticity (modulus of elasticity = elastic modulus) in the range of 20 MPa to 300 MPa, preferably 50 MPa to 200 MPa, more preferably 75 MPa to 150 MPa. The modulus of elasticity is measured, in particular in each case according to DIN EN ISO 527-3:2003-07 ("Plastics - Determination of tensile properties - Part 3: Test conditions for films and sheets - Publication date: 2003-07"), preferably at room temperature (25°C). The tensile modulus is checked on film test strips using a tensile tester, such as, for example, a tensile tester from ZwickRoell GmbH & Co. KG, Ulm, DE. The width of the film strip is preferably 15 mm ± 0.1 mm, the length of the film strip is preferably 100 mm ± 0.5 mm, and for film materials with particularly high elongation preferably 50 mm ± 0.5 mm. The test speed for a film length of 100 mm is 10 mm / min ± 1 mm / min, and for a film length of 50 mm is 5 mm / min ± 1 mm / min.

[0041] The adhesive layer is preferably arranged continuously and over the entire surface of the security element, which makes it possible to prevent stress differences which would lead to adhesion failure, particularly when the cover layer is peeled off.

[0042] In particular, the adhesive layer comprises a thermoplastic or a crosslinked or crosslinked polymer, in particular polymethyl methacrylate and / or polybutyl methacrylate.

[0043] Crosslinking specifically refers to a chemical reaction, preferably polymerization, in which macromolecules, especially polymers, are linked to form a three-dimensional network.

[0044] The adhesive layer is or has been preferably made on the basis of the following materials, selected individually or in combination from polymethyl methacrylate and polybutyl methacrylate. It is also possible for the adhesive layer to contain one or more additives, selected individually or in combination from fillers such as TiO2, BaSO4 or silica.

[0045] The adhesive layer preferably has a glass transition temperature Tg in the range of 20° C. to 50° C. Furthermore, the melting temperature Tm of the adhesive layer is preferably in the range of 40° C. to 150° C. In particular, the molar mass of the adhesive layer is in the range of 100 kg / mol to 350 kg / mol.

[0046] The adhesive layer has a thickness in the range of 0.2 μm to 20 μm, preferably in the range of 0.2 μm to 10 μm. It is particularly preferred if the adhesive layer has a thickness in the range of 3.5 μm to 20 μm, more preferably in the range of 3.5 μm to 10 μm, and / or in the range of 4 μm to 20 μm, more preferably in the range of 4 μm to 10 μm, and / or in the range of 6 μm to 20 μm, in particular in the range of 6 μm to 10 μm.

[0047] The adhesive layer is preferably transparent or translucent. The adhesive layer can have a milky optical impression. Cohesive failure in the adhesive layer can advantageously be particularly easily detected optically through the translucent and / or milky adhesive layer. For this purpose, the adhesive layer can be constituted by, for example, TiO2.

[0048] The adhesive layer may have a slightly rough surface before application. The surface roughness is preferably 0.4 μm to 2.0 μm, in particular 0.6 μm to 1.0 μm. The measurements required for this are preferably carried out using a microscope, in particular a Keyence VK-X3000, with the necessary software, possibly a VK analyzer.

[0049] The release layer has a thickness in particular in the range of 0.2 μm to 10 μm, preferably in the range of 0.2 μm to 5 μm. The release layer comprises or consists of a material selected individually or in combination from thermoplastics, thermoplastic elastomers, crosslinked polymers, UV crosslinked polymers, isocyanates, additives, catalysts, release agents. UV crosslinkable means in particular UV curable, and UV crosslinked means in particular UV curable.

[0050] The release layer is advantageously transparent. The release layer preferably has a smooth surface before the security element is laminated thereto. The release layer in particular has a low surface roughness before lamination, preferably an R3z value of less than 2 μm, more preferably an R3z value of less than 0.5 μm.

[0051] It has been shown that during lamination, the adhesive force of the release layer to the adjacent cover layer or adjacent recording layer can be stronger than the adhesive force in the adhesive layer, in particular the cohesive force of the adhesive layer.Furthermore, it is also possible to make the adhesive force of the release layer to the adjacent cover layer or adjacent recording layer stronger than the adhesive force between the adhesive layer and the cover layer or recording layer adjacent to the adhesive layer.Therefore, the peeling behavior of the laminate can be advantageously set as desired via the adhesive layer.

[0052] The reflective layer preferably consists of a material having a refractive index that differs from the refractive index of the replication layer by at least 0.2. The reflective layer preferably consists of or consists of a metal layer, a high refractive index layer (=HRI layer, layer with high refractive index), or a combination thereof. Typical materials for HRI layers are, for example, ZnS and / or TiO2. High refractive index layers are, for example, SiO x , MgO, TiO x, Al2O3, ZnO, ZnS, individually or in combination. The variable x is preferably in the range from 0 to 3, so that x=0, 1, 2, 3. The reflective layer may comprise chromium, aluminum, gold, copper, tin, indium, silver, and one or more alloys of the above metals, or may consist of the following metals, individually or in combination. It is also possible that the reflective layer comprises one or more metal oxides, preferably selected from aluminum oxide, chromium oxide, silicon oxide, indium tin oxide, titanium oxide, and combinations thereof. The reflective layer preferably has a refractive index of 1.9 or more for wavelengths in the range from 420 nm to 780 nm. The layer thickness of the reflective layer is in particular in the range from 40 nm to 200 nm, preferably in the range from 40 nm to 100 nm. The layer thickness is preferably related to the layers of the reflective layer. In the case of a multi-layer reflective layer, in particular one or more layers may have the specified layer thickness.

[0053] The reflective layer is usually evaporated or sputter-deposited in a vacuum. The reflective layer can also be applied or designed only in parts and / or have different thicknesses in partial areas.

[0054] On the side of the adhesive layer facing the replication layer and the reflective layer, the security element preferably has a stabilizing layer.The stabilizing layer achieves that, in particular in the case of, for example, a relatively thin adhesive layer, it is still prone to adhesion failure by itself, but can provide the adhesive layer with cohesive failure or can form the laminate in such a way that it is prone to cohesive failure when the cover layer is peeled off.The stabilizing layer advantageously simultaneously plays a protective function in the laminate by essentially retaining the brilliance of the optical effect in the laminate and serving to prevent warping of the security element, in particular the transfer layer with the security element.

[0055] The stabilizing layer preferably has a thickness in the range of 0.5 μm to 20 μm, more preferably 1 μm to 10 μm. In particular, it is possible for the stabilizing layer, preferably the adhesive layer, to have a thickness of 1 μm to 10 μm, and / or together with the thickness of the adhesive layer, a thickness of at least 1 μm and / or up to 40 μm and / or 0.1 to 20 times the thickness of the adhesive layer. In particular, it has proven advantageous for the ratio of the thickness of the adhesive layer to the thickness of the stabilizing layer to be in the range of 0.4 to 4.

[0056] It has proven advantageous for the stabilization layer to comprise or consist of a layer of a material having an elastic modulus in the range from 500 MPa to 1500 MPa.

[0057] In particular, the stabilizing layer comprises or consists of materials selected individually or in combination from thermoplastics, thermoplastic elastomers, crosslinked polymers, UV crosslinked polymers, isocyanates, additives, catalysts, release agents. The stabilizing layer can be formed by a varnish crosslinkable by radiation or a chemically reactive varnish, for example an epoxy resin.

[0058] The stabilizing layer preferably has a brittle behavior: during an attempt to separate tensile specimens of the laminate or during elastic modulus measurements, an elastic deformation of the stabilizing layer advantageously occurs.

[0059] The stabilizing layer is preferably transparent, in particular clear and transparent. The stabilizing layer preferably has a smooth surface. The stabilizing layer may be composed of several layers, for example an adhesion promoter layer for bonding with the reflective layer.

[0060] Between the release layer and the replication layer, one or more layers can be arranged which perform further functions. For example, a protective layer can be provided which is arranged between the release layer and the replication layer. This performs a stabilizing mechanical action against degradation, especially when the security element is laminated between the recording layer and the cover layer, especially when the recording layer and the cover layer comprise or consist of polycarbonate. For this purpose, such a protective layer is preferably thermally stabilized or is thermally stabilized, for example by crosslinking by radiation or by chemical reaction. The protective layer preferably comprises or consists of a material selected individually or in combination from thermoplastics, thermoplastic elastomers, crosslinked polymers or UV crosslinked polymers, isocyanates, additives, catalysts, release agents.

[0061] For laminating the security elements, a lamination method is preferably carried out or is carried out by means of a roll laminator or a lifting press.

[0062] In the case of a roll laminator, the recording layer, the cover layer and the security element arranged between these two layers can be inserted, for example, between at least two heated rollers. In the case of a lifting press, the recording layer, the cover layer and the security element arranged between these two layers can be inserted, for example, between heated plates.

[0063] Preferably, the lamination has a pressure of 10 N / cm acting on the recording layer, the cover layer and / or the security element. 2 ~400N / cm 2 , preferably 40N / cm 2 ~200N / cm 2The lamination is or has been carried out by applying a pressure of 0.5 to 100 .degree. C. to the recording layer, the cover layer and / or the security element from a heat source, in particular one or more heated rollers or one or more heated plates, at a temperature of more than 150.degree. C., preferably between 160.degree. C. and 210.degree. C. The lamination is or has been carried out by applying a contact time of the heat source with the recording layer and / or the cover layer ranging from 1 to 30 minutes. The contact of the heat source with the recording layer and the cover layer is preferably carried out directly or indirectly via a further layer. The above settings are preferably used for recording layers and cover layers made of or consisting of polycarbonate. For other materials, such as polyvinyl chloride, different settings regarding temperature and pressure can be used, adapted to the material to be treated.

[0064] Before or for the preparation of the cover layer or recording layer with the security element, it is possible to carry out the following steps, especially in the specified order. - providing a transfer film having a carrier layer and a transfer layer, the transfer layer carrying the security element and a release layer being disposed on a side of the security element facing the carrier layer, - applying a security element to the recording layer or to the cover layer.

[0065] As the carrier layer, a mechanically stable and therefore particularly self-supporting carrier film is advantageously used. Typically, the carrier layer consists of polyester, preferably polyethylene terephthalate (abbreviation: PET) or polyethylene naphthalate (abbreviation: PEN), or consists of a carrier layer. The thickness of the carrier layer is preferably in the range of 5 to 150 μm, more preferably 5 to 50 μm, even more preferably 10 to 25 μm. The carrier layer is preferably transparent.

[0066] The application of the security element is preferably carried out by the following steps, in a specifically specified order: - applying an adhesive layer to the recording layer or the cover layer. peeling the carrier layer from the transfer layer, so that the security element remains in the recording layer or cover layer.

[0067] The transfer layer can be completely or partially transferred through a predefined pattern, for example by means of an embossing die or an embossing roller. Alternatively, a particularly patterned, in-area printed adhesive can result in the transfer of the transfer layer in-area, so that the security element is formed with the printed adhesive and the in-area transferred transfer layer. The adhesive layer of the security element preferably comprises or consists of a printed adhesive layer.

[0068] During application, the release layer expediently ensures that the layer composite of the transfer layer can be peeled off from the carrier layer. In particular, when the security element is laminated, the release layer can surprisingly ensure that good adhesion is achieved with the adjacent cover layer or recording layer, especially if they contain or consist of polycarbonate. Thus, the release layer performs a double function, since it ensures, in particular, improved peelability during production and improved adhesion in the final product.

[0069] Between the release layer and the carrier layer one or more wax layers can be arranged. In particular, the separation of the transfer layer from the carrier can be improved by one or more, preferably thin, wax layers. The thickness of the wax layer in each case is preferably in the range of 1 nm to 50 nm. The one or more wax layers are preferably removed before laminating the security element. In particular, a strong adhesion between the release layer and the recording layer or the cover layer can be achieved.

[0070] The application of the adhesive layer is preferably carried out or is carried out by hot stamping. In particular, hot stamping can be carried out at temperatures of 80° C. to 300° C., 100° C. to 240° C., particularly preferably 100° C. to 180° C. Hot stamping is preferably carried out at a pressure of 10 N / cm 2 ~10000N / cm 2 , preferably 100N / cm 2 ~5000N / cm 2 The hot stamping is performed or is performed with a stamping pressure of preferably 0.01 to 2 seconds, more preferably 0.01 to 1 second.

[0071] The relief surface of the replication layer preferably forms optically active structures, which in particular means structures selected individually or in combination from diffractive surface reliefs, holographic surface reliefs, 1st order diffraction gratings, 0th order diffraction structures, blazed gratings, achromatic surface reliefs, surface reliefs in the form of lenses and / or lens grids, arrays of micromirrors, microprisms, microlenses, microfacets, freeform surfaces, mirror surfaces, matte structures, in particular isotropic or anisotropic matte structures.

[0072] The replication layer can further comprise or be a thermoplastic or a crosslinked polymer, preferably a UV crosslinked polymer. The replication layer preferably has a smooth surface before replication. The thickness of the replication layer is in particular in the range of 0.2 μm to 20 μm, preferably in the range of 0.2 μm to 10 μm.

[0073] The relief surface is molded or shaped into the replication layer by replication. This shaping can be effectively carried out thermoplastically, preferably under pressure and temperature, by structuring the surface with a tool having optically active structures as a corresponding negative relief. The replication layer can also be formed of a polymerizable or polymerized varnish, preferably consisting of monomers and oligomers, which is polymerized or has been polymerized after or during the introduction of the relief surface. This polymerization can be carried out by UV or electron beam irradiation. The replication layer can also represent a hybrid form by being thermoplastically deformed and then cured. The replication layer preferably comprises or consists of materials selected individually or in combination from thermoplastics, crosslinked polymers or UV crosslinked polymers, isocyanates, additives, catalysts, release agents.

[0074] The invention will now be described, by way of example only, with reference to some embodiments, using the accompanying drawings, in which: [Brief description of the drawings]

[0075] [Figure 1a] FIG. 1a is a schematic diagram showing a cross section of a laminate. [Figure 1b] FIG. 1b is a schematic cross-sectional view of a laminate. [Figure 1c] FIG. 1c is a schematic cross-sectional view of the laminate. [Figure 1d] FIG. 1d is a schematic diagram showing a cross section of the laminate. [Figure 2a] FIG. 2a is a diagram showing a schematic diagram of a method for producing a laminate. [Figure 2b] FIG. 2b is a diagram showing a schematic diagram of a method for producing a laminate. [Figure 3a] FIG. 3a is a diagram showing a schematic diagram of a method for producing a laminate. [Figure 3b] FIG. 3b is a diagram showing a schematic diagram of a method for producing a laminate. [Figure 4a]FIG. 4a is a schematic diagram showing a transfer film and a method for producing the same. [Figure 4b] FIG. 4b is a schematic diagram showing a transfer film and a method for producing the same. [Diagram 5] FIG. 5 is a schematic diagram showing the setup for the peel test. [Figure 6] FIG. 6 is a diagram showing a schematic diagram of fracture measurement curves for a brittle material and a ductile material. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0076] Figures 1a and 1b show in each case diagrammatically in cross section a laminate 1. The laminate 1 is preferably a security document.

[0077] The laminate 1 comprises a recording layer 11, a transparent cover layer 12 and a security element 20. The security element 20 is laminated between the recording layer 11 and the cover layer 12. The security element 20 has a release layer 21, an optional protective layer 22, a replication layer 23 with a relief surface arranged on the side opposite the release layer 21, a reflective layer 24 arranged on the relief surface and an adhesive layer 25.

[0078] The adhesive layer 25 forms the side of the security element 20 opposite the release layer 21. The laminate 1 is designed such that the adhesive layer 25 of the security element 20 can be split by the tensile forces exerted on the security element 20 by the recording layer 11 and the cover layer 12.

[0079] 1a shows laminate 1 in which adhesive layer 25 adheres to recording layer 11 and release layer 21 adheres to cover layer 12. FIG. 1b shows laminate 1 in which adhesive layer 25 adheres to cover layer 12 and release layer 21 adheres to recording layer 11.

[0080] In the depicted cross sections, the thickness of the layers is indicated in particular by height, i.e. the vertical dimension. Viewing the plane or main surface spanned by the laminate or its layers corresponds, for example, to a view from above. The adhesive layer 25 of the laminate 1 and of the laminate obtained by the method according to the invention can be split in particular by the tensile forces exerted on the security element 20 by the recording layer 11 and the cover layer 12. The presence of a splittable adhesive layer 25 or a predefined breaking point defined by the adhesive layer can be confirmed in particular by a peel test, which is described below on the basis of the description in relation to FIG. 5.

[0081] The joint between the cover layer 12 and the recording layer 11 is not shown in figures 1a and 1b. However, usually no intermediate space is provided in the laminate 1 between the cover layer 12 and the recording layer 11. The facing surfaces of the cover layer 12 and the recording layer 11 are fused in particular in the outer region of the security element 20, as for example shown in figures 1c and 1d and as can be achieved in particular by the method described herein. In particular, the cover layer 12 and the recording layer 11 form a monolithic body. By laminated or laminated is meant that the material bond joint between the recording layer 11 and the cover layer 12 has been or will be produced, preferably by a lamination method, so that the security element 20 is completely surrounded by the two layers 11 and 12. In particular, the security element 20 is laminated or stacked by fusing the recording layer 11 and the cover layer 12 together, in the process preferably completely surrounding the security element 20 when viewed perpendicular to the plane or main surface spanned by the laminate 1, and therefore when viewed from above in Figures 1a and 1b.

[0082] The recording layer 11 preferably comprises further substances, in particular doping. The energy absorption capacity of the recording layer 11 can be increased by doping. Substances for doping are in particular selected from chromium, erbium, neodymium, praseodymium, titanium, ytterbium. In this way, the items of information are inscribed or are inscribed in the recording layer 11, for example by means of a laser, preferably a YAG laser, preferably a Nd:YAG laser (neodymium-doped yttrium-aluminum-garnet laser). The emission wavelength of the YAG laser is preferably 1064 nm. In this way, the recording layer 11 can be processed by a laser, in particular through the cover layer 12, in order to inscribe the items of information in the recording layer 11. The security element 20 preferably overlaps such inscribed items of information and thus increases the protection against counterfeiting of the laminate 1, in particular the security document.

[0083] The recording layer 11 and / or the cover layer 12 comprise or consist of polycarbonate in a preferred embodiment. So-called composite laminates are also conceivable, in which the recording layer and / or the cover layer are made of different materials, for example PVC with a PET core. In particular, it is advantageous if the recording layer 11 and the cover layer 12 comprise or consist of polycarbonate and are or are joined to one another material-bondingly, in particular welded, by lamination. In this way, a particularly stable bond is achieved during lamination. The material-bonding bond, in particular of the polycarbonate layer consisting of almost 100% polycarbonate, is advantageously achieved by welding in a lamination process, which bond cannot be peeled off or can only be peeled off in a difficult manner by a forging machine. The peeling attempt, which makes use of the adhesion forces reduced in particular by the security element 20, is reproduced by the following test, in particular as explained with reference to FIG. 5, and can be made more difficult by cohesive failure and correspondingly selected geometry and material parameters, for example by increasing the peeling forces.

[0084] In the example of the laminate 1 described with reference to FIG. 1a, the following layer thicknesses can be implemented, for example: In this example, the cover layer 12 preferably has a layer thickness of 50 μm to 150 μm. In this example, the recording layer 11 preferably has a layer thickness of 50 μm to 150 μm. In this example, the adhesive layer 25 preferably has a thickness of 2 μm to 10 μm. In this example, the reflective layer 24 preferably has a thickness of 40 nm to 100 nm. In this example, the replication layer 23 preferably has a thickness of 0.2 μm to 10 μm. In this example, the optional protective layer 22 preferably has a thickness of 1.0 μm to 10.0 μm.

[0085] In the example of the laminate 1 described with reference to FIG. 1b, the following layer thicknesses can be implemented, for example: In this example, the cover layer 12 preferably has a layer thickness of 50 μm to 150 μm. In this example, the recording layer 11 preferably has a layer thickness of 50 μm to 150 μm. In this example, the adhesive layer 25 preferably has a thickness of 2 μm to 10 μm. In this example, the reflective layer 24 preferably has a thickness of 40 nm to 100 nm. In this example, the replication layer 23 preferably has a thickness of 0.2 μm to 10 μm. In this example, the optional protective layer 22 preferably has a thickness of 0.1 μm to 10 μm.

[0086] The adhesive layer 25 adheres to the recording layer 11 shown in Fig. 1a or to the cover layer 12 shown in Fig. 1b via an adhesive joint. The release layer preferably adheres to the cover layer 12 shown in Fig. 1a or to the recording layer 11 shown in Fig. 1b via a welded joint. The adhesive layer preferably adheres to the reflective layer via a material-adhesive joint and / or to the replication layer 23 via a material-adhesive joint. The reflective layer adheres in particular to the replication layer 23 via a material-adhesive joint.

[0087] The adhesion of the adhesive layer 25 to the directly adjacent layers, which may consist of the cover layer 12 or the recording layer 11, is advantageously higher than the cohesive strength of the adhesive layer 25. The adhesion within the adhesive layer 25, and in particular the cohesive strength of the adhesive layer 25, is preferably lower than the adhesion between the security element 20 and the recording layer 11 and also lower than the adhesion between the security element 20 and the cover layer 12.

[0088] In particular, it is advantageous if the adhesive layer 25 has the lowest yield point, in particular the lowest upper yield point, and / or the lowest modulus of elasticity of the layers of the security element 20, the recording layer 11 and / or the cover layer 12. The lowest cohesive and adhesive strength within the security element 20 or within the laminate 1 comprising the security element 20 is preferably the cohesive strength of the adhesive layer 25. As can be seen in figures 1a and 1b, the adhesive layer 25 is in particular arranged continuously over the entire surface of the security element 20.

[0089] The adhesive layer 25 preferably serves to bond the transfer layer of a transfer film carrying one or more security elements 20 according to the invention, for example as described with reference to Figs. 4a and 4b, to the substrate during application, i.e. in particular when the security elements 20 are applied to the cover layer 12 and / or the recording layer 11 as substrate. This can be an adhesive layer 25 activated by heat and pressure. A heated stamp of the shape defining the area to be transferred is typically used for this. Alternatively, the transfer can also be by so-called cold transfer. A printing layer of adhesive forming or constituted by the adhesive layer 25 of the laminate 1 is preferably printed on the transfer layer, the cover layer 12 or the recording layer 11 of the transfer film. The cover layer 12 or the recording layer 11 is then preferably brought into contact with the transfer layer, the printing layer of adhesive is cured and in particular the security element 20 is formed from the transfer layer and the printed adhesive layer. The adhesive layer 25 may be composed of several different layers, including, for example, one or more adhesion promoter layers, preferably in addition to a ductile layer, to ensure bonding of the adhesive layer 25 to the reflective layer 24 or any stabilizing layer that is optionally present.

[0090] It is also possible for the adhesive layer 25 to comprise or consist of a ductile layer, by which is meant in particular the layer of the security element which has the highest elongation at break compared to the other layers of the security element.

[0091] The adhesive layer 25 can have or consist of a ductile layer, which can be disrupted by cohesive failure. Cohesive failure is favored by the ductile layer, or adhesive failure is made more difficult, especially compared to brittle adhesive layers. This can increase the peel force.

[0092] In an advantageous embodiment, the adhesive layer 25, in particular the ductile layer, is made of a material having an elastic modulus in the range of 20 MPa to 300 MPa, preferably 50 MPa to 200 MPa, more preferably 75 MPa to 150 MPa. The elastic modulus is in each case measured according to DIN EN ISO 527-3:2003-07 ("Plastics - Determination of tensile properties - Part 3: Test conditions for films and sheets - Publication date: 2003-07"), preferably at room temperature (25°C). The tensile modulus is checked on film test strips using a tensile tester (for example from ZwickRoell GmbH&Co.KG, Ulm, DE). The width of the film strip is preferably 15 mm ± 0.1 mm, the length of the film strip is preferably 100 mm ± 0.5 mm, particularly for film materials with high elongation, 50 mm ± 0.5 mm. The test speed for a film length of 100 mm is 10 mm / min ±1 mm / min, and for a film length of 50 mm is 5 mm / min ±1 mm / min.

[0093] The adhesive layer 25 is preferably made or is made based on polymethylmethacrylate. The adhesive layer 25 may also contain one or more additives selected individually or in combination from fillers such as TiO2, BaSO4 or silica.

[0094] The adhesive layer 25, especially the ductile layer, may be milky white in color.

[0095] The adhesive layer 25, in particular the ductile layer, has a thickness in the range of 0.2 μm to 20 μm, preferably in the range of 0.2 μm to 10 μm. It is particularly preferred that the adhesive layer has a thickness in the range of 3.5 μm to 20 μm, more preferably in the range of 3.5 μm to 10 μm, and / or in the range of 4 μm to 20 μm, preferably in the range of 4 μm to 10 μm, and / or in the range of 6 μm to 20 μm, in particular in the range of 6 μm to 10 μm. The adhesive layer preferably has a glass transition temperature Tg in the range of 20° C. to 50° C. Furthermore, a melting temperature Tm of the adhesive layer in the range of 40° C. to 150° C. is preferred. In particular, the molar mass of the adhesive layer is in the range of 100 kg / mol to 350 kg / mol.

[0096] The adhesive layer 25 can have a slightly rough surface before being applied to the cover layer 12 or to the recording layer 11. The surface roughness is preferably between 0.4 μm and 2.0 μm, in particular between 0.6 μm and 1.0 μm. The measurements required for this are preferably carried out using a microscope, possibly a Keyence VK-X3000, with the necessary software, possibly a VK analyzer.

[0097] The release layer 21 has a thickness in particular in the range of 0.2 μm to 10 μm, preferably in the range of 0.2 μm to 5 μm, here for example in the range of 4 μm. It is also possible that the release layer 21 comprises or consists of a thermoplastic, a thermoplastic elastomer or a crosslinked polymer, preferably a UV crosslinked polymer. The release layer 21 comprises or consists of a material selected individually or in combination from a thermoplastic, a thermoplastic elastomer, a crosslinked polymer or a UV crosslinked polymer, an isocyanate, an additive, a catalyst, a release agent. The release layer 21 is advantageously transparent. The release layer 21 preferably has a low surface roughness before lamination, in particular an R3z value of less than 2 μm, preferably less than 0.5 μm.

[0098] For example, a reflective layer 24 made of aluminum with a layer thickness of 50 nm is used here. The reflective layer 24 can also comprise or consist of a metal layer, a high refractive index layer (=HRI layer) or a combination thereof. Typical materials for HRI layers are, for example, ZnS and / or TiO2. High refractive index layers are, for example, SiO x , MgO, TiO x , Al2O3, ZnO, ZnS, individually or in combination. The variable x is preferably in the range from 0 to 3, so that x=0, 1, 2, 3. The reflective layer 24 can comprise chromium, aluminum, gold, copper, tin, indium, silver, and one or more alloys of the above metals, or can consist of the following metals, individually or in combination. It is also possible that the reflective layer 24 comprises one or more metal oxides, preferably selected from aluminum oxide, chromium oxide, silicon oxide, indium tin oxide, titanium oxide, and combinations thereof. The reflective layer 24 preferably has a refractive index of 1.9 or more for wavelengths in the range from 420 nm to 780 nm. The layer thickness of the reflective layer 24 can be in the range from 40 nm to 200 nm, preferably in the range from 40 nm to 100 nm, here for example 50 nm. The reflective layer can also be designed only partially and / or have different thicknesses in partial regions.

[0099] On the side of the adhesive layer 25 facing the replication layer 23 and the reflective layer 24 , the security element 20 preferably has a stabilisation layer 26 .

[0100] The stabilizing layer 26 advantageously fulfills a protective function during lamination, by serving to ensure the brilliance of the optical effect during lamination and to prevent warping of the security element 20, in particular the transfer layer carrying the security element 20. At the same time, it can be achieved by the stabilizing layer 26 that, in particular in the case of, for example, a relatively thin adhesive layer 25, a predetermined breaking point can be provided by cohesive failure of the adhesive layer 25 or that a laminate 1 is formed which is more susceptible to cohesive failure when the cover layer 12 is peeled off, but which by itself still tends towards adhesive failure.

[0101] The stabilizing layer 26 preferably has a thickness in the range of 0.5 μm to 20 μm, more preferably 1 μm to 10 μm. In particular, the stabilizing layer 26 preferably has a thickness of 1 μm to 10 μm when the adhesive layer 25 is attached to the recording layer 11, and / or has a total thickness of at least 1 μm together with the thickness of the adhesive layer 25, and / or can have a thickness of 0.1 to 20 times the thickness of the adhesive layer 25.

[0102] It has been found to be advantageous that the stabilization layer 26 comprises or consists of a layer of a material having an elastic modulus in the range of 500 MPa to 1500 MPa.

[0103] The stabilizing layer 26 comprises or consists of materials selected, individually or in combination, from thermoplastics, thermoplastic elastomers or crosslinked polymers or UV crosslinked polymers, isocyanates, additives, catalysts, mold release agents, among others. The stabilizing layer 26 can also be formed by a varnish crosslinkable by radiation or a chemically reactive varnish, for example an epoxy resin.

[0104] The stabilization layer 26 preferably has a brittle behavior.

[0105] The stabilizing layer 26 is preferably transparent, in particular clear and transparent. The stabilizing layer 26 preferably has a smooth surface.

[0106] Between the release layer 21 and the replication layer 23, one or more layers can be arranged which perform further functions. For example, an optional protective layer 22 can be provided which is arranged between the release layer 21 and the replication layer 23. This performs a stabilizing mechanical action against degradation, in particular when the security element 20 is laminated to the recording layer 11 and the cover layer 12, which preferably consist of polycarbonate. For this purpose, such a protective layer 22 is preferably thermally stabilized or is thermally stabilized, for example by crosslinking by radiation or by chemical reaction. The protective layer 22 here is formed, for example, on the basis of thermoplastics and / or thermoplastic elastomers and / or crosslinked polymers, preferably UV crosslinked polymers, isocyanates, additives, catalysts, release agents.

[0107] It is further possible for the protective layer to be transparent, in particular highly transparent, and / or for the protective layer to have a low surface roughness, e.g. be smooth, in particular for the protective layer to have an R3z value of less than 2 μm, preferably less than 0.5 μm.

[0108] The relief surface of the replication layer 23 preferably forms an optically active structure. The relief surface is molded or cast in the replication layer 23 by replication. This shaping can be performed thermoplastically by structuring the surface under pressure and temperature with a tool having the optically active structure as a relief. The replication layer 23 can also be formed of a polymerizable or polymerized varnish, preferably consisting of monomers and oligomers, which is polymerized or has been polymerized after or during the introduction of the relief. This polymerization can be performed by UV irradiation or electron beam irradiation. The replication layer 23 can also represent a hybrid form by being thermoplastically deformable and subsequently hardenable. A corresponding relief surface is molded or cast in the replication layer 23 by a replication tool, in particular by thermal and / or UV replication. The surface relief can also be introduced by a laser. The replication layer 23 can also be a photosensitive layer, into which a relief surface is introduced by exposure to light. This relief surface is introduced by exposing the replication layer 23 to light in a pattern of varying light intensity and then, depending on the type of photosensitivity, using, in particular, a solvent, washing away or dissolving the areas of the replication layer 23 that were exposed to light or the areas of the replication layer 23 that were not exposed to light.

[0109] The replication layer 23 preferably has a smooth surface before replication. Materials of the replication layer 23 include or consist in particular of thermoplastics, cross-linked polymers, preferably UV cross-linked polymers. UV cross-linked polymers are hardened by UV radiation, in particular of wavelengths in the range of 100 nm to 400 nm. The replication layer 23 preferably includes or consists of materials selected individually or in combination from polyesters, polyurethanes, polyacrylates, ethylene-vinyl acetate copolymer resins, polymethyl methacrylates, epoxy resins, cellulose-based resins.

[0110] Preferably, the replication layer 23 does not soften when the security element is laminated. In particular, the softening temperature of the replication layer 23 is higher than the laminate temperature at the time of lamination. This allows the replication layer 23, in particular the structures molded in the replication layer 23, to remain stable during lamination. Here, for example, the shine of the decorative layer is preserved, for example by the relief surface molded therein remaining preserved, which ensures in particular a high level of protection against counterfeiting.

[0111] As relief surface one of the following relief surfaces or a combination of two or more relief surfaces is preferably provided here: diffractive surface relief, holographic surface relief, 1st order diffraction grating, 0th order diffraction structure, blazed grating, achromatic surface relief, surface relief in the form of lenses and / or lens grids, micromirrors, microprisms, microlenses, microfacets, freeform surfaces, mirror surfaces, matte structures, in particular isotropic or anisotropic matte structures.

[0112] The replication layer 23 preferably has different partial areas in which different relief surfaces are molded, which in particular differ in one or more relief parameters and / or consist of different ones of said relief surfaces. Some of said relief surfaces can also overlap one another.

[0113] The thickness of the replication layer 23 is, for example, 8 μm, preferably in the range of 0.2 μm to 20 μm, and more preferably in the range of 0.2 μm to 10 μm.

[0114] The surface roughness of the replication layer before replication is preferably very small, for example smooth, in particular the surface of the replication layer has an R3z value of less than 2 μm, preferably less than 0.5 μm.

[0115] Figures 2a, 2b, 3a and 3b show a method for producing a laminate 1, which is in particular a security document. For example, a laminate such as that described with respect to any of Figures 1a to 1d may be produced here and used in particular for the tests described.

[0116] In this method, for example, the following steps are carried out in a predetermined order. - preparing a recording layer 11; - providing a transparent cover layer 12; - Providing a security element 20.

[0117] The security element has a release layer 21, a replication layer 23 with a relief surface arranged on the side opposite the release layer 21, a reflective layer 24 arranged on the relief surface, and an adhesive layer 25 forming the side of the security element 20 opposite the release layer 21.

[0118] The security element 20 is applied to the cover layer 12, as shown in figures 2a and 2b, or applied to the recording layer 11, as shown in figures 3a and 3b. In this way, the security element 20 is adhered in particular to the cover layer 12 or to the recording layer 11 by means of the adhesive layer 25.

[0119] Depending on which of the two layers 11 and 12 the security element 20 is or has been applied to, the preparation of the respective other layer can also only take place afterwards. The recording layer 11 and the cover layer 12 are preferably arranged in such a way that the security element 20 is located between these two layers.

[0120] The security element 20 is then laminated between the recording layer 11 and the cover layer 12. If the procedure shown in figures 2a and 2b is followed, the adhesive layer 25 adheres to the cover layer 12 and the release layer 21 adheres to the recording layer 11. If the procedure shown in figures 3a and 3b is followed, the adhesive layer 25 adheres to the recording layer 11 and the release layer 21 adheres to the cover layer 12. The two options can also be combined in any way by using several security elements.

[0121] The adhesive layer 25 of the security element 20 is formed so that it can be divided by the tensile forces exerted on the security element 20 by the recording layer 11 and the cover layer 12 .

[0122] With regard to the specific design of the security element 20, reference is in particular also made to the described embodiment of the security element of the laminate according to the invention.

[0123] For laminating the security element 20, in particular a lamination method has been carried out or is carried out, preferably by means of a roll laminator or a lifting press.

[0124] In the case of a roll laminator, the recording layer 11, the cover layer 12 and the security element 20 arranged between these two layers can be inserted, for example, between at least two heated rollers. In the case of a lifting press, the recording layer 11, the cover layer 12 and the security element 20 arranged between these two layers can be inserted, for example, between heated plates.

[0125] Preferably, the lamination has a pressure of 10 N / cm acting on the recording layer 11, the cover layer 12 and / or the security element 20. 2 ~400N / cm 2 , preferably 40N / cm 2 ~200N / cm 2The lamination is or has been performed by a pressure of 150° C. or more, preferably 160° C. to 210° C., acting on the recording layer 11, the cover layer 12 and / or the security element 20 from a heat source, in particular one or more heated rollers or one or more heated plates. The lamination is or has been performed by a contact time of the heat source with the recording layer 11 and / or the cover layer 12 ranging from 1 min to 30 min. The contact of the heat source with the recording layer 11 and the cover layer 12 is preferably performed directly or indirectly via a further layer. The above settings are preferably used for the recording layer 11 and the cover layer 12 which are or consist of polycarbonate. For other materials, such as for example polyvinyl chloride, different settings regarding temperature and pressure can be used, adapted to the material to be processed.

[0126] Fig. 4a shows a transfer film and its production. Fig. 4b shows a further embodiment of a transfer film and its production method. Such a transfer film can be used to attach a security element 20 to the cover layer 12 or to the recording layer 11.

[0127] In particular, as explained with respect to Figures 2a, 2b, 3a and 3b, before or in order to prepare the security element 20, the cover layer 12 or the recording layer 11 comprising the security element 20, it is possible to carry out the following steps, in the order particularly specified: - preparing a transfer film as described with reference to FIG. 4a or 4b comprising a carrier layer 31 and a transfer layer, the transfer layer comprising a security element 20 and a release layer 21 being arranged on the side of the security element 20 facing the carrier layer 31, - applying the security element 20 to the recording layer 11 or to the cover layer 12 .

[0128] As carrier layer 31, a mechanically stable and therefore in particular self-supporting carrier film 31 is advantageously used. Typically, the carrier layer comprises or consists of a polyester, preferably polyethylene terephthalate (abbreviation: PET) or polyethylene naphthalate (abbreviation: PEN). The thickness of the carrier layer is preferably in the range of 5 to 150 μm, more preferably 5 to 50 μm, even more preferably 10 to 25 μm. The carrier layer is preferably transparent.

[0129] The mounting of the security element 20 is carried out, for example, by the following steps, in a specifically specified order. - applying an adhesive layer 25 to the recording layer 11 or to the cover layer 12, peeling the carrier layer 31 off the transfer layer, leaving the security element 20 in the recording layer 11 or in the cover layer 12 .

[0130] The transfer layer can be transferred completely or in areas according to a predefined pattern, for example by means of an embossing die or embossing roller. Alternatively, a specifically patterned, in-area printed adhesive can result in the transfer of the transfer layer in areas, so that the security element is formed from the printed adhesive and the in-area transferred transfer layer, for example without an adhesive layer or with an adhesive layer, preferably as an adhesion promoter layer supplemented by a printed adhesive layer. The adhesive layer 25 of the security element 20 then preferably comprises or consists of a printed adhesive layer.

[0131] The application of the adhesive layer 25 to the recording layer 11 or the cover layer 12 is or is preferably carried out by hot stamping. In particular hot stamping is possible which is carried out at temperatures of 80° C. to 300° C., 100° C. to 240° C., particularly preferably 100° C. to 180° C. Hot stamping is preferably carried out at a pressure of 10 N / cm 2 ~10000N / cm 2 , preferably 100N / cm 2 ~5000N / cm2 The hot stamping is performed or is performed with a stamping pressure of preferably 0.01 to 2 seconds, more preferably 0.01 to 1 second.

[0132] As shown in FIG. 4a, a transfer film can be produced by sequentially applying an optional wax layer 32, a release layer 21, an optional protective layer 22 and a replication layer 23 onto a carrier layer 31.

[0133] During application, the release layer 21 advantageously ensures that the layer complex of the transfer layer can be peeled off from the carrier layer 31. When laminated to the laminate 1, this layer in particular ensures that good adhesion with the adjacent cover layer 12 or recording layer 11 is achieved. Between the release layer 21 and the carrier layer 31 one or more wax layers can be arranged, such as the optional wax layer 32 shown in figures 4a and 4b. In particular, the separation of the transfer layer from the carrier can be improved by one or more, preferably thin, wax layers. The thickness of the wax layer in each case is preferably in the range of 1 nm to 50 nm. The wax layer 32 is preferably removed before laminating the security element. In particular, a strong bond between the release layer and the recording layer or the cover layer can be achieved here.

[0134] Once the replication layer 23 has been applied, a relief surface can be formed in the replication layer 23 by replication, as already mentioned above. A reflective layer 24 can then be applied to the relief surface, in particular over the entire surface or over parts or areas of the surface, for example in the form of a pattern. For this, the reflective layer is, for example, evaporated or sputter-deposited in a vacuum. As shown in FIG. 4b, an optional stabilization layer 26 or, as shown in FIG. 4a, an adhesive layer 25 can then be applied, preferably directly to the reflective layer 24, but also to the replication layer 23, in particular if the reflective layer 24 has been evaporated over parts of the surface. As shown in FIG. 4b, the optionally present stabilization layer 26 can additionally be applied between the adhesive layer 25 and the replication layer 24, in particular between the adhesive layer 25 and the replication layer 23, in which case the adhesive layer 25 is applied to the stabilization layer 26.

[0135] The adhesive layer 25 can also consist of several layers. For example, the adhesive layer 25 can in particular comprise, in addition to a ductile layer, one or more adhesion promoter layers to ensure the bonding of the adhesive layer 25 to the reflective layer 24 or to the optionally present stabilizing layer 26. The layer of the adhesive layer 25 which adheres to the cover layer 12 or to the recording layer 11 of the laminate 1 can in particular be applied as a hot glue layer on the transfer layer or can be applied in a later step as a cold glue layer on the transfer layer and optionally on the already present layer of the adhesive layer 25 or on the recording layer 11 or on the cover layer 12.

[0136] FIG. 5 shows the setup for a peel test as described above, in particular a test according to ISO / IEC 10373-1:2006(E) paragraph 5.3.

[0137] In particular for the peel test, the optionally preconditioned card is cut into test pieces 10 mm wide. For example, FIG. 5 shows a schematic cross-section of such a test piece of laminate 1.

[0138] For example, all layers on one side of the security element 20 are removed, preferably over a length of 5 mm to 10 mm. The security element 20 is in particular a Kinegram®. The cover layer 12 is peeled off from the core and from the recording layer 11, in particular with a sharp knife or the like. The peeling is only partial.

[0139] The peeled end is preferably fixed to the holder of the tensile tester via a holding clamp or by an adhesive tape 40. Preferably, a right angle is created between the peeled layer, in particular the cover layer 12, which is fixed to the tensile tester, and the non-peeled layers, in particular the corresponding parts of the cover layer 12, the recording layer 11 and the security element 20. In particular, a right angle is created between the cover layer 12 and the recording layer 11. It is expedient to fix the bottom of the laminate 1 or a specimen thereof, in particular the recording layer 11, on a stabilizer plate. During the tensile measurement, the peeled film layer can be guided onto a roller. The adhesion (peel strength) is preferably plotted on a graph and subsequently evaluated, although the first and last 5 mm of the measurement are preferably not taken into account. The results are shown, for example, in N / 10 mm.

[0140] It is also possible to carry out measurements in the absence of a security element, for example to test the adhesion between the cover layer and the recording layer.

[0141] The influence of the different layers of the laminate 1 on the peel force can be advantageously ascertained by peel force tests. The dominant influence on the peel force is the dissipation in the adhesive, which energy is converted in the cohesive failure. Adhesion failure, especially in the case of delamination of the structure at the interface between the adhesive layer 25 and the cover layer 12 or the recording layer 11, results in a much lower peel force than in the case of cohesive failure. Advantageously, a peel force of 3.5 N / 10 mm strip width or more is possible for peeling the cover layer 12.

[0142] The measurement of the elastic modulus can be carried out in particular as described below: The elastic modulus can be measured according to DIN EN ISO 527-3:2003-07 ("Plastics - Determination of tensile properties - Part 3: Test conditions for films and sheets - Publication date: 2003-07"), preferably at room temperature (25°C). The tensile modulus is ascertained on film test strips using a tensile tester (e.g. ZwickRoell GmbH & Co. KG, Ulm, DE). The width of the film strip is preferably 15 mm ± 0.1 mm, the length of the film strip is preferably 100 mm ± 0.5 mm, and 50 mm ± 0.5 mm for film materials with particularly high elongation. The test speed for a film length of 100 mm is 10 mm / min ± 1 mm / min, and for a film length of 50 mm is 5 mm / min ± 1 mm / min.

[0143] Figure 6 shows, as a comparative example, the progression of a ductile material fracture 6 and a brittle material fracture 5 in a force-displacement diagram. The y-axis shows the force F of the force-displacement diagram, and the x-axis the displacement L. In this respect, the brittle material fracture 5 is characterized by a very steep rise in the measured force and a sharp drop when the tensile strength of the material is reached. On the other hand, in the case of a ductile material fracture 6, the steepness of the measurement curve is significantly less and the force remains at a practically constant level when the yield stress is reached. This material behavior is also shown in particular in the results of the peel test. The dissipation in the region of the fracture or crack tip during the peeling of the cover layer remains at the highest possible level, especially in the case of cohesive failure, but not in the case of adhesive failure.

[0144] The experimental examples for checking and comparison tests are shown below.

[0145] For the verification, corresponding patterns were produced, for example. In particular, a 19 μm thick hot stamping film was used as the basis (B944059, Leonhard Kurz Stiftung & Co. KG, Furth, DE). This film had the following structure: PET carrier, release layer, protective layer, replication layer. A relief surface was molded into the replication layer and a cylindrical metal plate was pressed against it. The plate had a temperature of 180 °C and a pressure of 100 N / cm 2 The production speed was 20 m / min.

[0146] A reflective layer consisting of zinc sulfite (ZnS) was then applied to the relief surface by vacuum coating with a thickness of 60 nm. In a gravure printing process, an adhesive based on polymethylmethacrylate was applied, and the adhesive layer was varied in terms of layer thickness for the investigation. After removing the solvent, the following layer thicknesses could be determined: 1 μm, 4 μm and 6 μm.

[0147] The security element was then applied to a 100 μm thick transparent cover layer made of polycarbonate (Makrofol ID 6-2, Covestro AG, Leverkusen, DE) or to a 100 μm thick transparent recording layer made of polycarbonate (Makrofol ID 6-2, Covestro AG, Laserable). For this purpose, a hot stamp transfer machine was used, with a stamp temperature of 170° C. and a stamp pressure of 250 N / cm. 2 A stamping time of 0.5 seconds was used. Afterwards, cards were produced with a structure according to standard ISO / IEC 7810:2003(E), with a 100 μm thick white polycarbonate (Makrofol ID 6-4, from Covestro AG) being used for the remaining part of the card structure. In the pattern of experimental series 1, the adhesive layer of the security element was adhesively bonded to the cover layer, and in the pattern of experimental series 2, the adhesive layer of the security element was adhesively bonded to the recording layer. The laminate processing required for this involved a processing temperature of 190 °C and a pressure of 120 N / cm 2 A pressing pressure of 100 mm and a pressing time of 15 minutes were selected. Cards were then punched out of the laminate.

[0148] The results of experiment series 1 show the peel forces for the recording layer and the security element. The results of experiment series 2 show the peel forces for the cover layer and the security element. The peel forces were verified by a peel test performed according to ISO / IEC 10373-1:2006(E); paragraph 5.3 and / or the peel test described above.

[0149] The results of these measurements are shown in Table 1. [Table 1]

[0150] As can be seen from table 1, the adhesive thickness has an influence on the peel force in experimental series 1. With increasing layer thickness, the peel force increases. For a layer thickness of 1 μm, the peel force is 0.8 N / 10 mm specimen width, which is due to adhesion failure between the adhesive layer and the recording layer of the security element. On the other hand, when the layer thickness is increased to 4 μm, cohesive failure occurs, which results in an increase in the peel force to 2.6 N / 10 mm specimen width. When the layer thickness is increased to 6 μm, the peel force increases to 3.9 N / 10 mm, which results in cohesive failure of the adhesive. This behavior is also observed in experimental series 2. Again, the peel force is the lowest at 0.7 N / 10 mm for a layer thickness of 1 μm, which results in adhesion failure between the adhesive layer and the cover layer. When the layer thickness is increased to 4 μm, cohesive failure of the adhesive occurs, which is indicated by an increase in the peel force to 2.4 N / 10 mm specimen width. Cohesive failure also occurred when the layer thickness was 6 μm, and the peel force increased to 4.9 N / 10 mm specimen width. Notably, a divisible adhesive layer can be confirmed in different laminate structures.

[0151] A comparison between Experiment Series 1 and Experiment Series 2 demonstrated the following points in particular: The bonding of the adhesive layer to the cover layer and the recording layer may result in similar peel forces. -When the adhesive layer thickness is 1 μm, the two structures show adhesion failure, which changes to cohesion failure when the layer thickness is 4 μm. In both experimental series it is possible to achieve a peel force of at least 3.5 N / 10 mm for an adhesive layer with a thickness of 6 μm. It may also be that the arrangement of the security element in the layer structure of the security document has no influence on the fracture behavior of the adhesive layer of the security element in the peel test. - To achieve a peel force of at least 3.5 N / 10 mm specimen width, it is possible that the peeling of the adhesive layer does not occur as a pure cohesive failure. Transient changes typically observed during the transition from cohesive to adhesive failure, e.g. a temporary decrease or increase in the peel force, can be neglected under defined conditions, in particular according to standard ISO / IEC 10373-1:2006(E); paragraph 5.3.

[0152] FIG. 7 shows a schematic example of crack growth in a cross section of a laminate with an adhesive layer 25 and a layer 1112 directly adjacent to the adhesive layer 25. The layer 1112 is either the cover layer 11 or the recording layer 12. The adhesive layer 25 and the layer 1112 therefore have in particular an interface formed between these layers or a contact surface of the two layers. The cracks 51 and 52 are shown in FIG. 7 by dashed lines. In the case of a peel test and / or an attempt to peel the cover layer 11 and / or the recording layer 12, and thus in particular the layer 1112 shown, one of the two cracks 51 and 52 may occur, for example.

[0153] In particular, as shown by crack 51, the tip of the crack may briefly strike the interface between adhesive layer 25 and the layer 1112 immediately adjacent to the adhesive layer during cohesive failure, but does not propagate along it as separation progresses.

[0154] As explained in particular with reference to the crack 52, it is possible to design the laminate in such a way that the adhesive layer 25 peels off at one or more partial surfaces at the interface with the directly adjacent layer 1112, here in the region 520, which may be the case for example in the case of adhesion failure. However, these one or more partial surfaces in the region 520 advantageously have a smaller surface area than the residual surface of the interface, in particular so that the peel force is at least 3.5 N / 10 mm. The residual surface is present here by way of example in the region 521 of the crack 52. The residual surface of the interface has a residue of the adhesive layer 25 in particular in the region 521. The surface area is ascertained in particular when viewed along a line perpendicular to the plane spanned by the interface, and thus when viewed, for example, from below to above in FIG. 7.

[0155] The residual surface present, for example, in region 521 in particular covers at least 50%, preferably at least 80%, more preferably at least 90% of the surface area of ​​the boundary surface, and / or the partial surface present, for example, in region 520 in particular covers less than 50%, preferably less than 20%, more preferably less than 10% of the surface area of ​​the boundary surface.

[0156] Advantageously, in the case of unevenness in the stack, tensile stresses can reach local peaks when the layer 1112 is peeled off, which can lead to local adhesive failures, but also to mainly cohesive failures, while still ensuring a high overall peel force, especially in the case of relatively thin adhesive layers with a layer thickness of at least 3.5 μm.

[0157] Thus, in a preferred embodiment, the adhesive layer advantageously has a thickness of at least 3.5 μm, preferably at least 4 μm, in particular at least 6 μm. [Explanation of symbols]

[0158] 1. Laminate 11 Cover Layer 12 Recording layer 1112 Layer directly adjacent to adhesive layer 20 Security Elements 21 Peeling layer 22 Protective layer 23 Replication layer 24 Reflective layer 25 Adhesive layer 26 Stabilizing Layer 31 Career Film 32 Wax layer 40 Clamp or adhesive tape r radius α angle x Length of peel layer L Displacement F force 5 Brittle material failure 6. Failure of ductile materials 51, 52 Crack 510 Partial surface area 520 Residual surface area

Claims

1. A laminate (1), in particular a security document, comprising: A security element (20) is laminated between a recording layer (11), a transparent cover layer (12), and the recording layer (11) and the cover layer (12), The security element (20) comprises a release layer (21), a replication layer (21) with a relief surface arranged on the side opposite the release layer (21), a reflective layer (24) arranged on the relief surface, and an adhesive layer (25) forming a side of the security element (20) opposite the release layer (21), a) the adhesive layer (25) adheres to the recording layer (11) and the release layer (21) adheres to the cover layer (12), or the adhesive layer (25) adheres to the cover layer (12) and the release layer (21) adheres to the recording layer (11); b) said laminate (1) is designed such that said adhesive layer (25) of said security element (20) can be split by a tensile force exerted on said security element (20) by said recording layer (11) and said cover layer (12).

2. 2. A laminate according to claim 1, characterized in that said adhesive layer (25) has the lowest yield point, in particular the upper yield point, and the lowest modulus of elasticity among the layers of the security element.

3. 3. The laminate according to claim 1 or 2, characterized in that the adhesive strength of the adhesive layer (25) to the directly adjacent layers of the cover layer (12) or the recording layer (11) is higher than the cohesive strength of the adhesive layer (25).

4. Laminate according to one of claims 1 to 3, characterized in that the peel force for peeling said cover layer (12), preferably from said security element (20), is greater than or equal to 3.5 N / 10 mm strip width, in particular measured in a peel test, preferably at a peel angle (α) of 90°.

5. The adhesive strength within the adhesive layer (25), in particular the cohesive strength of the adhesive layer (25), is - lower than the adhesion between said security element (20) and said recording layer (11)(11); and A laminate according to one of claims 1 to 4, characterized in that the adhesion between the security element (20) and the cover layer (12)(12) is lower.

6. 6. The laminate according to claim 1, characterized in that among the cohesive and adhesive forces within the security element (20) or within the laminate (1) comprising said security element, the cohesive force of the adhesive layer (25) is the lowest.

7. Laminate according to one of the claims 1 to 6, characterized in that the adhesive layer (25) comprises or consists of a ductile layer, in particular a ductile layer meaning the layer in which the breaking elongation of the security element (20) is greatest.

8. 8. Laminate according to one of the claims 1 to 7, characterized in that the adhesive layer (25), in particular the ductile layer, consists of a material having an elastic modulus in the range of 20 MPa to 300 MPa, preferably 50 MPa to 200 MPa, more preferably 75 MPa to 150 MPa.

9. 9. The laminate according to claim 1, wherein the adhesive layer (25) has a layer thickness in the range of 0.2 μm to 20 μm, preferably in the range of 0.2 μm to 10 μm and / or preferably in the range of 3.5 μm to 20 μm, further preferably in the range of 3.5 μm to 10 μm and / or in the range of 6 μm to 20 μm, in particular in the range of 6 μm to 10 μm.

10. Laminate according to one of the preceding claims, characterized in that the adhesive layer (25) comprises a thermoplastic or a crosslinkable or crosslinked polymer, in particular polymethyl methacrylate and / or polybutyl methacrylate.

11. The adhesive layer (25) is semi-transparent and / or made of e.g. TiO ２ , BaSO ４ 11. A laminate according to claim 1, characterized in that it comprises one or more additives selected individually or in combination from the group consisting of tungsten, tungsten phosphate, tungsten phosphates ...

12. Laminate according to one of the preceding claims, characterized in that the release layer (21) has a thickness in the range of 0.2 μm to 10 μm, preferably in the range of 0.2 μm to 5 μm.

13. Laminate according to one of the preceding claims, characterized in that the release layer (21) consists or consists of a thermoplastic, a thermoplastic elastomer, a crosslinked polymer or a UV crosslinked polymer.

14. Stack according to one of the claims 1 to 13, characterized in that the relief surface of the replication layer (23) forms optically active structures.

15. Laminate according to one of the preceding claims, characterized in that the replication layer (23) consists or consists of a thermoplastic or a crosslinked polymer or a UV crosslinked polymer.

16. Stack according to one of the preceding claims, characterized in that the thickness of the replication layer (23) is in the range of 0.2 μm to 20 μm, preferably in the range of 0.2 μm to 10 μm.

17. Stack according to one of the preceding claims, characterized in that the reflective layer (24) consists of a metal layer, a high refractive index layer, or a combination thereof.

18. Stack according to one of the preceding claims, characterized in that the reflective layer (24) has a refractive index greater than 1.9 for wavelengths in the range from 420 nm to 780 nm.

19. Stack according to one of the preceding claims, characterized in that the layer thickness of the reflective layer (24) is in the range of 40 nm to 200 nm, preferably in the range of 40 nm to 100 nm.

20. 20. The laminate according to claim 1, characterized in that the security element (20) has a stabilization layer (26) on the side of the adhesive layer (25) facing the replication layer (23) and the reflective layer (24).

21. Laminate according to one of the preceding claims, characterized in that the stabilisation layer (26) has a thickness ranging from 0.5 μm to 20 μm, preferably from 1 μm to 10 μm.

22. Stack according to one of claims 1 to 21, characterized in that the ratio between the thickness of the adhesive layer (25) and the thickness of the stabilizing layer (26) is in the range of 0.4 to 4, in particular when the adhesive layer (25) adheres to the recording layer (11).

23. Stack according to one of the preceding claims, characterized in that the stabilisation layer (26) comprises or consists of a layer of material having an elastic modulus in the range from 500 MPa to 1500 MPa.

24. Laminate according to one of the preceding claims, characterized in that the stabilization layer (26) comprises or consists of a thermoplastic, a thermoplastic elastomer or a crosslinked polymer, preferably a UV crosslinked polymer.

25. Stack according to one of the preceding claims, characterized in that the recording layer (11) and the cover layer (12) comprise or consist of polycarbonate.

26. 26. The laminate according to claim 1, characterized in that the thickness of the cover layer (12) is in the range of 1.25 to 250 μm relative to the thickness of the adhesive layer (25), the sum of the thicknesses of the adhesive layer and the cover layer is in the range of 26 μm to 270 μm, and the cover layer (12) has a thickness in the range of 25 μm to 250 μm.

27. Stack according to one of the preceding claims, characterized in that the recording layer (11) has a thickness in the range of 25 μm to 250 μm.

28. Stack according to one of the preceding claims, characterized in that the adhesive layer (25) is adhered to the cover layer (12) or to the recording layer (11) via an adhesive joint.

29. Stack according to one of the preceding claims, characterized in that the release layer (21) is adhered to the cover layer (12) or to the recording layer (11) via the adhesive joint.

30. 30. The laminate according to claim 1, wherein the adhesive layer (25) is adhered to the reflective layer (24) via a material-adhesive joint and / or to the replication layer (23) via a material-adhesive joint.

31. A method for the manufacture of a laminate, in particular a security document, comprising the steps of: - providing a recording layer (11), - providing a cover layer (12); - preparing a security element (20), in particular a security element according to one of claims 1 to 30, said security element (20) having a release layer (21), a replication layer (23) with a relief surface arranged on the side opposite said release layer (21), a reflective layer (24) arranged on said relief surface and an adhesive layer (25) forming the side of said security element (20) opposite said release layer (21), said security element (20) being or being glued to said cover layer (12) or to said recording layer (11) by means of said adhesive layer (25), - said security element (20) between said recording layer (11) and said cover layer (12), a) the adhesive layer (25) adheres to the recording layer (11) and the release layer (21) adheres to the cover layer (12), or the adhesive layer (25) adheres to the cover layer (12) and the release layer (21) adheres to the recording layer (11); b) laminating said security element (20) in such a way that said adhesive layer (25) of said security element (20) can be divided by a tensile force exerted on said security element (20) by said recording layer (11) and said cover layer (12).

32. Method according to claim 31, characterized in that for laminating the security element (20) a roll laminator or a lifting press is used for laminating.

33. The lamination acts on the recording layer (11), the cover layer (12) and / or the security element (20) with a pressure of 10 N / cm ２ ~400N / cm ２ , preferably 40 N / cm ２ ~200N / cm ２ 33. The method according to claim 31 or 32, characterized in that it is carried out at a pressure of

34. Method according to one of claims 31 to 33, characterized in that the lamination is carried out by a temperature of 150°C or more, preferably between 160°C and 210°C, acting on the recording layer (11), on the cover layer (12) and / or on the security element from a heat source, in particular one or more heated rollers or one or more heated plates.

35. The method according to one of claims 31 to 34, characterized in that the lamination by the contact time of the heat source with the recording layer (11) and / or the cover layer (12) is in the range of 1 minute to 30 minutes.

36. Prior to or for the preparation of said cover layer (12) or said recording layer (11) comprising said security element (20), in a given order: - providing a transfer film comprising a carrier layer (31) and a transfer layer, said transfer layer comprising said security element (20) and said release layer (21) being arranged on the side of said security element (20) facing said carrier layer, - applying said security element (20) to said recording layer (11) or to said cover layer (12), The method according to one of claims 31 to 35, characterized in that the method is carried out as follows:

37. The application of the security element (20) is carried out in the specified order: - applying said adhesive layer to said recording layer (11) or to said cover layer (12), The method according to one of claims 31 to 36, characterized in that it is carried out by the step of - peeling off the carrier layer (31) from the transfer layer.

38. Method according to one of claims 31 to 37, characterized in that the application of the adhesive layer (25) is carried out by hot stamping.

39. The method according to one of claims 31 to 38, characterized in that the hot stamping is carried out at a temperature of 80°C to 300°C, preferably 100°C to 240°C, particularly preferably 100°C to 180°C.

40. The hot stamping is performed at a pressure of 10 N / cm 2 ~10000N / cm 2 , preferably 100 N / cm 2 ~5000N / cm ２ 40. The method according to claim 31, characterized in that it is carried out with a stamping pressure of 0.15 to 100 .mu.m.

41. The hot stamping is carried out with a stamping time of 0.01 to 2 seconds, preferably 0.01 to 1 second. The method according to one of claims 31 to 40.

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