EP3363652B1 - Security element transfer material and method for manufacturing the same - Google Patents

Description

The invention relates to a security element transfer material, comprising: a security element layer composite which has a plurality of layers, including at least one feature layer developing an optically variable effect and an adhesive layer, the feature layer being the layer that is applied after a security element has been transferred a value document substrate faces a viewer; a carrier substrate which is detachably connected to the feature layer of the security element layer composite; a mask layer having at least one recess, which is such that the security element layer composite in the area of the at least one recess of the mask layer can be glued to the value document substrate by the action of pressure and possibly heat by means of the adhesive layer and then detached from the carrier substrate, in the area outside of the at least one recess in the mask layer, the security element layer composite is prevented from sticking to the value document substrate and the subsequent detachment of the security element layer composite from the carrier substrate is prevented. The invention also relates to a method for producing the security element transfer material.

Valuables, such as branded items or documents of value, in particular banknotes, are often equipped with security elements which allow the authenticity of the valuable object to be checked and which at the same time serve as protection against unauthorized reproduction. The security elements used for this are often not individually but in shape provided by transfer tapes with a multiplicity of security elements designed as transfer elements. It is characteristic of transfer tapes that the security elements are prepared on a carrier layer, with the order of the layers of the transfer elements having to be reversed, as it should later be present on the object to be protected. During the transfer, the carrier layer is typically peeled off from the layer structure of the security elements. On the side opposite the carrier layer, the transfer tapes have an adhesive layer, usually made of a heat-sealing adhesive or heat-sealing lacquer, which melts during the transfer of the security elements and bonds the security elements to the object to be secured. The transfer tape with the heat-sealing adhesive layer is placed on the object and pressed on by means of a heated transfer stamp or a transfer roller and transferred to the object in the shape of the heated transfer stamp. Transfer elements, transfer belts and the transfer of transfer elements to target substrates are for example in the EP 0 420 261 B1 and the WO 2005/108108 A2 described.

In practice it has been shown that especially when using more stable and / or flexible UV embossing lacquers, transfer elements, for example transfer patches, do not tear off cleanly at the border of the heated area. This leads to unclean edges and possibly also to the fact that remnants of the film composite, which were torn from the layer composite in the non-bonded area, stick to the transferred patches. These residues are undesirable because they later loosen and, in the form of impurities, impair subsequent processing steps, e.g. printing processes.

Instead of the shaping of the transfer elements by the transfer stamp during the transfer process, the individual transfer elements can also already be present on the transfer belt in the desired outline shape. The prefabrication of separate individual security elements makes sense, for example, if the security elements have a layer structure that makes it difficult to sever the entire layer structure precisely during the transfer process. This is the case, for example, when the layer structure of the security element to be transferred contains a permanent carrier substrate, for example a plastic film. Carrier substrates within the layer structure of security elements are useful if the security elements have to be made particularly stable, for example if they have to be self-supporting because they are to be used to close a through opening in the object to be secured. Depending on the object and size of the opening to be closed, high demands can be placed on the stability of the security elements. Banknotes, for example, are exposed to high stresses during their period of circulation, are tapped, bent and, under certain circumstances, exposed to moisture. The security elements must be able to withstand these stresses in the same way as the banknote paper itself, since otherwise there would be the risk that the through opening in the banknote would be exposed after a certain period of circulation.

Security elements, the layer structure of which comprises a stable carrier substrate, typically a plastic film, must be present on a transfer material as prefabricated individual elements, which means that the outline of the security elements must be precut in the security element material. The pre-cutting can be carried out, for example, by means of a laser.

The problem arises that the depth of cut has to be controlled very precisely in order, on the one hand, to cut through the entire layer structure of the security element, but, on the other hand, not to damage the carrier material that is separated during the transfer. Plastic films are usually used as carrier materials. Plastic films have a high tear resistance, but a low tear resistance. If they are cut, it can hardly be avoided that the security element transfer material present as a continuous material tears in some places in the course of the process of transferring the security elements to objects of value. It must also be taken into account that the layer structures to be cut or the carrier foils that are not to be cut are materials with thicknesses in the micrometer range. The security element layer structures typically have thicknesses in the range from about 20 μm to 30 μm, and the carrier films typically have thicknesses in the range from 10 μm to 20 μm. With the precision required here, it is problematic to carry out a cutting process in such a way that the security element-layer composite is completely severed, but the cutting process is stopped in good time so that the carrier film is not cut anywhere. Due to the partially cut carrier film, however, the security element transfer material loses its stability and may even tear, which is why an exact and smooth application of the security elements from the continuous material to the products to be protected is no longer guaranteed.

A security element transfer material in the form of a continuous material, in which the security elements are pre-cut in the desired outline shapes, and the pre-cut elements then without the risk of tearing the Carrier material can be transferred to products to be secured is from the WO 2010/031543 A1 known. The security element transfer material is an endless material, in particular a tape with a length of several hundred meters and a width of a few millimeters / centimeters up to several meters. The security element transfer material has a security element layer composite, ie the actual security element material, and a temporary carrier, ie the material on which the security elements are “stored”. The temporary carrier is based on a carrier layer composite, consisting of a first and a second temporary carrier substrate, which are permanently bonded by means of an adhesive layer. The security element layer composite is connected to a temporary carrier either directly or by means of a release layer. The release layer is of a conventional type and facilitates the detachment of the security elements from the temporary carrier during the transfer process to an object of value. The temporary carrier is located on the side of the security element layer composite which, after the transfer of the security elements, faces a viewer. The term “temporary” carrier substrates expresses that, in contrast to the “permanent” carrier substrate, these carrier substrates are not part of the security elements. The formation of the temporary carrier as a carrier layer composite prevents the stability of the temporary carrier from being impaired by cutting the temporary carrier when the contour shapes of the security elements are cut. A comparable result cannot simply be achieved by making a single temporary carrier film correspondingly thicker, since plastic films have a low tear resistance, i.e. if a film is only slightly cut, it tears further and under certain circumstances completely. Different with the carrier layer composite, Consists of a first and a second temporary carrier substrate, which are permanently bonded by means of an adhesive layer: even if one of the temporary carrier substrates is completely severed, the further temporary carrier substrate (or possibly the further temporary carrier substrates) generally remains undamaged and accordingly stable. The adhesive also forms an additional "buffer zone" between the temporary carrier substrates.

The one in the WO 2010/031543 A1 The method described consists of weeding the patch film before application. For this purpose, the shapes of the patch are punched into the layers to be transferred with a punch, ie the layers are broken through with the punch. When weeding, these layers are then peeled off in the areas outside the patch, while they remain on the carrier film in the patch areas. This ensures that the patches have clean edges after application. A disadvantage of this method, however, is that the layer structure must have sufficient stability for weeding, which can be done, for example, by introducing a stabilizing film layer. However, this is again associated with an increase in the thickness of the finished patch, which is undesirable in practice.

The WO 2010/072339 A2 and the WO 2012/164011 A1 each describe a method for producing a security element and a transfer film.

The patent U.S. 4,246,307 describes a laminated sticker and a laminated identity card, each with tamper protection, where an attempt to peel off the laminate at certain points would result in a tearing of a backing layer.

The invention is based on the object of providing a method for transferring a transfer element, for example a transfer patch, in which, on the one hand, a small thickness of the finished patch and, on the other hand, a reliable transfer of the patch with clean edges can be achieved.

This object is achieved by the combination of features defined in main claim 1 and in the independent claims 6, 7 and 10. Further developments are the subject of the dependent claims.

Summary of the invention

(First aspect of the invention) The security element transfer material according to claim 1.

The carrier substrate of the security element transfer material is in particular a film. The carrier substrate of the security element transfer material can, however, also be a carrier layer composite consisting of a first film and a second film, which are permanently glued by means of an adhesive layer.

(Second aspect of the invention) A method of manufacturing a security element transfer material according to claim 6.

(Third aspect of the invention) A method for manufacturing a security element transfer material according to claim 7.

(Fourth aspect of the invention) A method of manufacturing a security element transfer material according to claim 10.

Detailed description of the invention

In the context of this invention, viewing in incident light is illumination of the document of value from one side and viewing of the document of value from the same side. Viewing in incident light is thus present, for example, when the front of the document of value is illuminated and also viewed.

In the context of this invention, viewing in transmitted light is illumination of a document of value from one side and viewing of the document of value from another side, in particular the opposite side. Viewing in transmitted light is thus present, for example, when the back of the document of value is illuminated and the front of the document of value is viewed. The light thus shines through the value document.

A value document within the meaning of the invention can be, for example, banknotes or identity documents, but also shares, certificates, postage stamps, checks, tickets, tickets, flight tickets, ID cards, visa stickers or the like, as well as labels, seals, packaging or other elements. The simplifying term “document of value” therefore always includes documents of the type mentioned in the following. The term value document also includes security paper for the production of bank notes. The term bank note includes in particular one Paper bank note, a polymer bank note, or a film composite bank note.

The transfer element, i.e. the security element to be transferred, can in particular be a transfer patch or transfer label or a transfer strip or transfer thread. The invention is described in the following detailed description using the example of a transfer patch, and is therefore not to be construed as being restricted to a patch.

Instead of the term feature layer, the term functional layer is also used here. The functional layer can be a single (functional) layer or several (functional) layers.

Instead of the phrase “a mask layer having at least one recess”, the term perforated mask is also used here.

Transfer patches are used, for example, in the first series of EURO banknotes, e.g. in the form of the hologram patch applied to the EURO 50 banknote.

According to the invention, a transfer material can be realized in accordance with the following preferred embodiment:

1. Provision of a transfer film structure:

The starting point is a conventional transfer film structure, such as that used, for example, for the application of transfer strips. Such a structure is based on a carrier film, one or more functional layers on it and a heat-sealing lacquer layer. The Functional layers provide optically variable security features, for example embossed holograms, micromirror elements, subwavelength structures and the like. The optically variable security features are generally provided by an embossed lacquer, for example a UV embossed lacquer, with microstructures embossed therein and a metallization that is present at least in some areas. Often there are additional layers, for example protective lacquers or primers, which are then followed by the heat-sealing lacquer at the end. The heat-sealing lacquer layer can actually also consist of several layers of different lacquers. The functional layers have only weak adhesion to the carrier film, which can be achieved, for example, by poor adhesion of the embossing lacquer to the carrier film or by introducing a special separating layer.

2. Applying a shadow mask:

According to the invention, a perforated mask is applied to the above-mentioned transfer film structure. The perforated mask can in particular be provided by a perforated film from which the shapes of the desired patches are punched out. Such a perforated film is advantageously laminated or glued onto the transfer film structure. This can be done with a laminating adhesive or simply by using the adhesive strength of the heat seal lacquer that is already present. Advantageously, the side facing the heat-sealing lacquer can be provided beforehand with a primer which enables the perforated film and functional layers to be bonded better. Perforated film and functional layers can also only be glued in areas. Theoretically, the perforated film can only stick to the functional layers when the heat-sealing lacquer is melted on during application. In practice, however, it is advantageous to prevent the perforated film from slipping by gluing at least in certain areas.

3. Application:

During application, the patch is heated as usual, the heat-sealing lacquer melting on and adhering to the (value document) substrate. The (value document) substrate can be, for example, a paper or polymer substrate or a paper / polymer composite substrate.

The heating can take place in certain areas (i.e. in an area that is slightly larger than the patch itself) or over the entire surface. If the film structure is then separated from the (value document) substrate, the functional layers remain in the patch area on the (value document) substrate, since the heat seal lacquer to the paper ensures stronger adhesion than the adhesion between the carrier film and the functional layers. The functional layers remain on the carrier film in the area outside the patch.

1. i) Verhinderung des Verklebens von Funktionsschichten und (Wertdokument-)Substrat.
2. ii) Stabilisierung des Schichtverbunds zur Verhinderung des Aufreißens der Funktionsschicht in Bereichen außerhalb des Patches.

The mask film fulfills two tasks:

1. i) Preventing functional layers and (value document) substrate from sticking together.
2. ii) Stabilization of the layer composite to prevent the functional layer from tearing open in areas outside the patch.

Further preferred design variants:

Alternative methods of providing the shadow mask:

1. a) Instead of lamination of a finished perforated mask onto the transfer composite (see the above preferred embodiment, the lamination usually being registered or in register), the corresponding film can also only be perforated after lamination. For this purpose, the film is only glued to the transfer film in the areas outside of the later patch (by melting or by activating the heat seal lacquer or with the help of a laminating adhesive applied in areas). Due to the positioning tolerances of the gluing and die cut, it is advantageous to let the gluing end at a sufficient distance from the patch. The patch shapes are then punched out and the film is removed in the areas of the holes, for example by means of compressed air or by pulling over a sharp edge.
   A major advantage of this variant is that the patches do not have to be torn out of the functional layer composite after application to the (value document) substrate (i.e. a break within the functional layers has to occur), but rather the functional layers at the edge of the patch already clean by punching are severed. This results in very clean patch edges.
2. b) Another, alternative method for providing a shadow mask is based on the printing process of creating a shadow mask, e.g. on the basis of a relatively thick UV lacquer.

Further preferred design variants:

Functional layers:

Micromirrors, hologram structures, subwavelength structures or (for example embedded) microlenses, for example, can be incorporated in the functional layers. Microlenses can in particular be present in combination with microimages formed in a separate plane and in this way generate optically variable security features in the form of so-called moiré magnifiers, modulo mappers, tilt images and the like. Security features based on microlenses in combination with microimages are, for example, from the WO 2006/087138 A1 known.

Micromirrors, hologram structures, etc. are usually coated with a metallization that is present at least in some areas, which can consist of a metal, e.g. Al or Ag, a high-index coating, e.g. ZnS or TiO ₂ , or a color-changing three-layer reflector / dielectric / absorber system (e.g. a Al / SiO2 / Cr structure).

Heat sealing lacquer:

It is essential for the heat-sealing gel lacquer that at the end of the application it ensures the desired adhesion through pressure and possibly increased temperature. The heat can melt it and / or activate it. Provision can also be made for the heat-sealing lacquer to be post-treated (post-crosslinking), e.g. by means of UV radiation.

Foil thickness:

The perforated film is preferably as thin as possible. Films with thicknesses in a range from 4.5 µm to 19 µm can be used with advantage. A polyethylene terephthalate (PET) film is preferably used as the film. Thicker films, for example a 19 μm thick PET film, are preferably used as carrier films. In the embodiments in which the functional layers are punched into by means of punching, something is generally also punched into the carrier film. It must be ensured here that the carrier film does not tear after the patch has been applied to the (value document) substrate. According to an advantageous variant, not a single carrier film is used as the carrier film, but a laminating composite consisting of two films, as is the case with the WO 2010/031543 A1 is known (e.g. a 12 µm thick film and a 19 µm thick film that are glued together): then only one of the two films is punched out during punching, while the second film remains undamaged. A single punched film tears more easily than a laminated composite, since the "tear" of a film requires more force than tearing it further.

Application of the transfer patch to the (value document) substrate:

For a better transfer, it can be advantageous to pull the carrier film off the rest of the layer composite over a sharp edge (or a wedge).

Other preferred parameters:

• The functional layers preferably contain embossing lacquers, which typically have a total thickness in a range from 2 μm to 7 μm exhibit. Depending on the structure type, typical embossing depths can be in a range from 100 nm to 3.5 µm, for example.
• The total thickness of the patch without carrier film is preferably below 50 μm, more preferably below 30 μm and particularly preferably below 20 μm.
• Typical patch dimensions are e.g. widths of 5 mm to 25 mm and heights of e.g. 5 mm to 70 mm.
• The patch shape can be chosen arbitrarily. Oval shapes are usually easier to apply than e.g. rectangular shapes. A jagged edge may be beneficial. In particular, the variant of punching the functional layers (see above) also enables the application of patches with complex outlines that are difficult to apply under normal conditions.

Further general remarks:

The embossed structure that can be used according to the invention is in particular embossed into an embossed lacquer. In the context of the present application, the expression “optically variable effect” includes not only holograms but also hologram-like diffraction structures, that is to say, for example, structures that do not produce a defined image but rather a blurred colored impression. The term "optically variable effect" also subsumes diffraction patterns, structures with a color shift effect, cinema forms, structures with a microlens effect, structures with isotropic or anisotropic scattering effects or with other interference effects, sub-wavelength structures, moth-eye structures, microlens structures and microstructures for moire magnifiers or modulo mappers , Micromirror structures and microprismatic structures.

• einer reflektierenden Schicht (insbesondere einer metallischen, reflektierenden Schicht);
• einer semitransparenten (Spiegel-)Schicht (die insbesondere von der Gruppe bestehend aus Al, Ag, Ni, Cr, Cu, Au und einer Legierung eines oder mehrerer der vorstehend genannten Elemente gewählt ist); und
• einer zwischen der reflektierenden Schicht und der semitransparenten (Spiegel-)Schicht angeordneten dielektrischen Schicht,

wobei sich die Farbe des mehrschichtigen Aufbaus mit der Änderung des Betrachtungswinkels ändert.Preferred reflective embossed structures contain, for example, a multilayer structure capable of interference

• a reflective layer (in particular a metallic, reflective layer);
• a semitransparent (mirror) layer (which is selected in particular from the group consisting of Al, Ag, Ni, Cr, Cu, Au and an alloy of one or more of the aforementioned elements); and
• a dielectric layer arranged between the reflective layer and the semitransparent (mirror) layer,

wherein the color of the multilayer construction changes with the change of the viewing angle.

It is possible to create a first appearance of the multilayer structure capable of interference when viewing the front side in reflected light and a second appearance of the multilayer structure capable of interference when viewing the front side in transmitted light, e.g. by means of cutouts in the reflective layer and / or the semitransparent layer Layer. Such a film security element with different reflected-light / transmitted-light appearances is from WO 2009/149831 A2 known. For example, the semitransparent layer can have a multiplicity of cutouts arranged in a grid-like manner, which in their entirety result in a character, an image or a pattern. The pattern created in this way is visible in incident light and disappears in transmitted light. Alternatively and / or additionally, a different reflected-light / transmitted-light appearance of the multilayer structure can be achieved by combining the structure with a relief structure, in particular a diffractive relief structure, a micro-optical relief structure or a sublambda structure.

• die beiden semitransparenten Spiegelschichten werden bevorzugt von Al oder Ag gewählt; die dielektrische Schicht ist insbesondere eine SiO₂-Schicht;
• im Falle, dass jede der beiden semitransparenten Spiegelschichten auf Al beruht, liegt die jeweilige bevorzugte Schichtdicke in einem Bereich von 5 nm bis 20 nm, insbesondere bevorzugt in einem Bereich von 10 nm bis 14 nm; die dielektrische SiO₂-Schicht hat vorzugsweise eine Schichtdicke in einem Bereich von 50 nm bis 450 nm, weiter bevorzugt in einem Bereich von 80 nm bis 260 nm, wobei die Bereiche von 80nm bis 100nm und von 220nm bis 240nm speziell für die Bereitstellung eines Gold/Blau-Farbwechsels besonders bevorzugt werden;
• im Falle, dass jede der beiden semitransparenten Spiegelschichten auf Ag beruht, liegt die jeweilige bevorzugte Schichtdicke in einem Bereich von 15 nm bis 25 nm; die dielektrische SiO₂-Schicht hat vorzugsweise eine Schichtdicke in einem Bereich von 50 nm bis 450 nm, weiter bevorzugt in einem Bereich von 80 nm bis 260 nm, wobei die Bereiche von 80nm bis 100nm und von 220nm bis 240nm speziell für die Bereitstellung eines Gold/Blau-Farbwechsels besonders bevorzugt werden.

Further preferred reflective embossed structures contain, for example, a multilayer structure with two semitransparent layers and a dielectric layer arranged between the two semitransparent layers, the multilayer structure having different color tones when viewed in incident light on the one hand and when viewed in transmitted light on the other hand, especially when viewed in Incident light appears gold and shows a blue hue when viewed in transmitted light. The two different shades are in particular complementary colors. Such a multilayer structure is based in particular on two semitransparent mirror layers and a dielectric layer arranged between the two semitransparent mirror layers. Such a multi-layer structure, which appears golden when viewed in incident light and shows a blue hue when viewed in transmitted light, is, for example, from FIG WO 2011/082761 A1 known. A metal selected from the group consisting of Al, Ag, Ni, Cr, Cu, Au and an alloy of one or more of the aforementioned elements is particularly suitable as the semitransparent mirror layer, Al or Ag being preferred as the semitransparent mirror layer and Al is particularly preferred. Suitable multilayer structures with two semitransparent mirror layers and a dielectric layer arranged between the two semitransparent mirror layers preferably have the following physical properties:

• the two semitransparent mirror layers are preferably selected from Al or Ag; the dielectric layer is in particular an SiO ₂ layer;
• in the event that each of the two semitransparent mirror layers is based on Al, the respective preferred layer thickness is in a range from 5 nm to 20 nm, particularly preferably in a range from 10 nm to 14 nm; the dielectric SiO ₂ layer preferably has a layer thickness in a range from 50 nm to 450 nm, more preferably in a range from 80 nm to 260 nm, the ranges from 80 nm to 100 nm and from 220 nm to 240 nm being particularly preferred especially for providing a gold / blue color change;
• in the event that each of the two semitransparent mirror layers is based on Ag, the respective preferred layer thickness is in a range from 15 nm to 25 nm; the dielectric SiO ₂ layer preferably has a layer thickness in a range from 50 nm to 450 nm, more preferably in a range from 80 nm to 260 nm, the ranges from 80 nm to 100 nm and from 220 nm to 240 nm especially for providing gold / Blue color change are particularly preferred.

• im Auflicht Magenta, im Durchlicht Blau-Grün;
• im Auflicht Türkis, im Durchlicht Orange-Gelb;
• im Auflicht Gold, im Durchlicht Blau-Violett;
• im Auflicht Silber, im Durchlicht Violett.

The above-mentioned multi-layer structures not only enable the creation of a semitransparent functional layer, which appears gold when viewed in reflected light and shows a blue hue when viewed in transmitted light, but further color changes can be generated depending on the choice of layer thickness, especially of the dielectric layer, e.g.

• Magenta in incident light, blue-green in transmitted light;
• turquoise in incident light, orange-yellow in transmitted light;
• gold in incident light, blue-violet in transmitted light;
• Silver in incident light, violet in transmitted light.

Further preferred reflective embossed structures contain, for example, a liquid crystal layer which shows a different color when viewed in incident light than when viewed in transmitted light. Alternatively and / or additionally, a different reflected-light / transmitted-light appearance can be achieved by combining the liquid crystal layer with a relief structure, in particular a diffractive relief structure, a micro-optical relief structure or a sublambda structure.

Further preferred reflective embossed structures contain, for example, a printed layer with an effect pigment composition which when viewed in reflected light shows a different color than when viewed in transmitted light, in particular a gold / blue color change, a gold / violet color change, a green-gold / Magenta color change, a purple / green color change or a silver / opaque color change. Such printing inks are, for example, in the WO 2011/064162 A2 described. Alternatively and / or additionally, a different reflected-light / transmitted-light appearance can be achieved by combining the printing layer with a relief structure, in particular a diffractive relief structure, a micro-optical relief structure or a sublambda structure.

The relief structure forming a diffractive structure is in particular a hologram structure. The dimensions of the structural elements of the diffractive structure are preferably in the order of magnitude of the light wavelength, more preferably in a range that is greater than 100 nm and less than 1 μm, a range greater than 300 nm and less than 1 μm being particularly preferred.

The relief structure forming a micromirror arrangement is also referred to herein as a micro-optical relief structure. The production of a micro-optical relief structure is known in the prior art (see e.g. WO 2014/060089 A2 ). The dimensions of the structural elements of the micromirror arrangement are preferably in a range that is greater than 1 μm and less than 40 μm, a range greater than 1 μm and less than 30 μm being particularly preferred. The dimensions of the structural elements of the micromirror arrangement have, for example, one Height up to 15 µm and a lateral extension up to 30 µm. Both the height and the lateral extent of the structural elements of the micromirror arrangement are preferably greater than 1 μm.

Further preferred micro-optical relief structures are, for example, from FIG WO 2007/079857 A1 known. Here, the reflective microstructure has the form of a mosaic made up of a large number of reflective mosaic elements, which are characterized by the parameters size, outline shape, relief shape, reflectivity and spatial orientation and which form a predetermined motif by different groups of mosaic elements with different characteristic parameters incident light in reflect different spatial areas, and in which the mosaic elements have a lateral dimension below the resolution limit of the eye.

Further exemplary embodiments and advantages of the invention are explained below with reference to the schematically greatly simplified figures, the representation of which has not been reproduced true to scale and proportion in order to increase the clarity.

Figuren 1 und 2

die Herstellung eines erfindungsgemäßen Transfermaterials gemäß einem ersten Ausführungsbeispiel;

Figuren 3 und 4

die Applikation eines Transfer-Patches auf ein Wertdokumentsubstrat;

Figuren 5 bis 8

die Herstellung eines erfindungsgemäßen Transfermaterials gemäß einem zweiten Ausführungsbeispiel;

Figuren 9 und 10

die Applikation eines Transfer-Patches auf ein Wertdokumentsubstrat.

Show it:

Figures 1 and 2

the production of a transfer material according to the invention according to a first embodiment;

Figures 3 and 4

the application of a transfer patch to a value document substrate;

Figures 5 to 8

the production of a transfer material according to the invention according to a second embodiment;

Figures 9 and 10

the application of a transfer patch to a value document substrate.

Figures 1 and 2 illustrate the production of a transfer material according to the invention according to a first embodiment.

According to the Figure 1 First, a transfer film structure is provided. The transfer film structure is based on a carrier film 1, one or more functional layers 2 located thereon and a heat-sealing lacquer layer 3. The functional layers 2 provide optically variable security features, for example embossed holograms, micromirror elements, subwavelength structures and the like. The optically variable security features are generally provided by an embossed lacquer, for example a UV embossed lacquer, with microstructures embossed therein and a metallization that is present at least in some areas. The functional layers 2 have only weak adhesion to the carrier film 1, which can be achieved, for example, by poor adhesion of the embossing lacquer to the carrier film 1 or by introducing a special separating layer.

According to the Figure 2 is on the in the Figure 1 A perforated mask 4 is applied to the transfer film structure shown. The perforated mask 4 can in particular be provided by a perforated film from which the shapes of the desired patches are punched out. Such a perforated film 4 is advantageously laminated onto the transfer film structure. This can be done with a additional laminating adhesive (in the Figure 2 not shown) or simply by using the adhesive strength of the heat-sealing lacquer 3 which is already present. The side facing the heat-sealing lacquer 3 can advantageously be provided beforehand with a primer which enables the perforated film 4 and functional layers 2 to be better bonded. Perforated film 4 and functional layers 2 can also only be glued in areas.

Figures 3 and 4 illustrate the application of a transfer patch according to the first embodiment to a value document substrate, in the present example a security paper for the production of banknotes.

During application, the patch is heated as usual, the heat-sealing lacquer 3 melting on and glued to the paper substrate 5 (see FIG Figure 3 ). The heating can take place in areas (ie in an area that is slightly larger than the patch itself) or over the entire area.

Like in the Figure 4 is shown, the film structure 6 is then separated from the paper substrate 5. Thus, the functional layers 2 remain in the patch area on the paper substrate 5, since the heat-sealing lacquer 3 to the paper 5 ensures stronger adhesion than the adhesion between carrier film 1 and functional layers 2. In the area The functional layers 2 remain on the carrier film 1 outside the patch.

1. i) die Verhinderung des Verklebens von Funktionsschichten 2 und Papiersubstrat 5; und
2. ii) die Stabilisierung des Schichtverbunds zur Verhinderung des Aufreißens der Funktionsschicht 2 in Bereichen außerhalb des Patches.

The masking film 4 fulfills two tasks:

1. i) preventing the functional layers 2 and paper substrate 5 from sticking together; and
2. ii) the stabilization of the layer composite to prevent the functional layer 2 from tearing open in areas outside the patch.

Figures 5 to 8 illustrate the production of a transfer material according to the invention according to a second embodiment.

According to the Figure 5 First, a transfer film structure is provided. The transfer film structure is based on a carrier film 7, one or more functional layers 8 thereon and a heat-sealing lacquer layer 9. The functional layers 8 provide optically variable security features, for example embossed holograms, micromirror elements, subwavelength structures and the like. The optically variable security features are generally provided by an embossed lacquer, for example a UV embossed lacquer, with microstructures embossed therein and a metallization that is present at least in some areas. The functional layers 8 have only weak adhesion to the carrier film 7, which can be achieved, for example, by poor adhesion of the embossing lacquer to the carrier film 7 or by introducing a special separating layer.

According to the Figure 6 becomes the one in the Figure 5 The transfer composite shown is provided with a lamination adhesive 10 in the areas outside of the later patch (the lamination adhesive 10 is not absolutely necessary; alternatively, the already existing heat-sealing lacquer 9 could be melted or activated in areas) and then glued with a film 11. Due to the positioning tolerances of the gluing and die cut, it is advantageous to let the gluing end at a sufficient distance from the patch.

According to the Figure 7 the patch shapes are then punched out (the solid lines 12 illustrate the punching tool) and the film 11 is removed in the areas of the holes, for example by means of compressed air or by pulling over a sharp edge.

A major advantage of this variant is that the patches do not have to be torn out of the functional layer assembly after application to the value document substrate (i.e. a break within the functional layers must occur), but the functional layers at the edge of the patch are already cleanly cut through by punching (see those in the Figure 8 Punched lines shown in dashed lines 13). This results in very clean patch edges.

Figures 9 and 10 illustrate the application of the transfer patch according to the second embodiment to a value document substrate, in the present example a security paper for the production of banknotes.

During application, the patch is heated as usual, the heat-sealing lacquer 9 melting on and glued to the paper substrate 14 (see FIG Figure 9 ). The heating can take place in areas (ie in an area that is slightly larger than the patch itself) or over the entire area.

Like in the Figure 10 is shown, the film structure 15 is then separated from the paper substrate 14. Thus, the functional layers 8 remain in the patch area on the paper substrate 14, since the heat-sealing lacquer 9 to the paper 14 ensures stronger adhesion than the adhesion between carrier film 7 and functional layers 8. In the area The functional layers 8 remain on the carrier film 7 outside the patch.

Claims (10)

1. A security element transfer material, comprising

   - a security element layer composite which has a multiplicity of layers, including at least one feature layer (2, 8) developing an optically variable effect and an adhesive layer (3, 9), wherein the feature layer is the layer which faces a viewer after a security element has been transferred to a value document substrate; and

   - a carrier substrate (1, 7) which is detachably connected to the feature layer (2, 8) of the security element layer composite; characterized in that the security element transfer material additionally comprises:

   - a mask layer (4, 11) having at least one cutout, which is configured such that the security element layer composite in the region of the at least one cutout of the mask layer (4, 11) can be adhesively bonded to the value document substrate (5, 14) by the action of pressure and possibly heat by means of the adhesive layer (3, 9) and then detached from the carrier substrate (1, 7), wherein, in the region outside the at least one cutout of the mask layer (4, 11), the security element layer composite is prevented from adhering to the value document substrate (5, 14) and from a subsequent detachment of the security element layer composite from the carrier substrate (1, 7).
2. The security element transfer material according to claim 1, wherein the mask layer (4, 11) is formed by a foil.
3. The security element transfer material according to claim 1 or 2, wherein the feature layer (2, 8) developing an optically variable effect is based on a reflective embossed structure.
4. The security element transfer material according to claim 3, wherein the reflective embossed structure is configured as follows: (a) a reflective diffractive structure or (b) a reflective microstructure in the form of a mosaic of a multiplicity of reflective mosaic elements which are determined by the parameters size, contour shape, relief shape, reflectivity and spatial alignment and which form a predetermined motif in that different groups of mosaic elements with different characteristic parameters reflect incident light into different spatial regions, and in which the mosaic elements have a lateral dimension below the resolution limit of the eye.
5. The security element transfer material according to claim 3 or 4, wherein the reflective embossed structure (i) as reflective layers has opaque metal layers, or (ii) as reflective layers has transparent, highly refractive layers, or (iii) as reflective layers has thin-film elements with a color shift effect, in particular with a reflective layer and a semitransparent layer and an interposed dielectric layer, or (iv) as reflective layers has layers of liquid crystalline material, in particular of cholesteric liquid crystalline material, or (v) as reflective layers has printed layers based on effect pigment compositions with viewing angle-dependent effect or with different colors when viewed in incident light and when viewed in transmitted light or (vi) as reflective layers has the following multilayer structure: two semitransparent layers and one dielectric layer arranged between the two semitransparent layers, wherein the multilayer structure has different color tones when viewed in incident light on the one hand and when viewed in transmitted light on the other hand.
6. A method for manufacturing a security element transfer material according to any of claims 1 to 5, comprising

   a) making available a carrier substrate (1, 7);

   b) supplying the carrier substrate (1, 7) with a security element layer composite which has a multiplicity of layers, including at least one feature layer (2, 8) developing an optically variable effect and an adhesive layer (3, 9), wherein the feature layer is the layer which faces a viewer after a security element has been transferred to a value document substrate, wherein the carrier substrate (1, 7) is detachably connected to the feature layer (2, 8) of the security element layer composite;

   c) separately making available a mask layer (4, 11) having at least one cutout;

   d) adhesively bonding the mask layer to the security element layer composite obtained in step b), so that a security element transfer material is obtained in which the security element layer composite in the region of the at least one cutout of the mask layer (4, 11) can be adhesively bonded to a value document substrate by the action of pressure and possibly heat by means of the adhesive layer (3, 9) and then detached from the carrier substrate (1, 7), wherein, in the region outside the at least one cutout of the mask layer (4, 11), the security element layer composite is prevented from adhering to the value document substrate and from a subsequent detachment of the security element layer composite from the carrier substrate (1, 7).
7. A method for manufacturing a security element transfer material according to any of claims 1 to 5, comprising

   a) making available a carrier substrate (1, 7);

   b) supplying the carrier substrate (1, 7) with a security element layer composite which has a multiplicity of layers, including at least one feature layer (2, 8) developing an optically variable effect and an adhesive layer (3, 9), wherein the feature layer (2, 8) is the layer which faces a viewer after a security element has been transferred to a value document substrate, wherein the carrier substrate is detachably connected to the feature layer (2, 8) of the security element layer composite;

   c) applying a foil suitable for producing a mask layer (4, 11) having at least one cutout onto the security element layer composite obtained in step b), wherein the foil is adhesively bonded to the security element layer composite merely in the region outside the at least one cutout to be produced and in the region of the at least one cutout to be produced is not adhesively bonded to the security element layer composite;

   d) producing at least one cutout in the foil obtained in step c) in order to produce a mask layer (4, 11) in this manner, so that a security element transfer material is obtained in which the security element layer composite in the region of the at least one cutout of the mask layer (4, 11) can be adhesively bonded to a value document substrate by the action of pressure and possibly heat by means of the adhesive layer (3, 9) and then detached from the carrier substrate, wherein, in the region outside the at least one cutout of the mask layer (4, 11), the security element layer composite is prevented from adhering to the value document substrate (5, 14) and from a subsequent detachment of the security element layer composite from the carrier substrate (1, 7).
8. The method according to claim 7, wherein in step d) the production of at least one cutout in the foil obtained in step c) is effected by means of punching and the punched-out foil material is removed.
9. The method according to claim 8, wherein in the step of punching out not only the foil to be converted into a mask layer (4, 11) is supplied with punch lines, but also the security element composite layer to be transferred is provided with punch lines.
10. A method for manufacturing a security element transfer material according to any of claims 1 to 5, comprising

    a) making available a carrier substrate (1, 7);

    b) supplying the carrier substrate (1, 7) with a security element layer composite which has a multiplicity of layers, including at least one feature layer (2, 8) developing an optically variable effect and an adhesive layer (3, 9), wherein the feature layer (2, 8) is the layer which faces a viewer after a security element has been transferred to a value document substrate, wherein the carrier substrate is detachably connected to the feature layer (2, 8) of the security element layer composite;

    c) supplying the security element layer composite obtained in step b) with a mask layer (4, 11) having at least one cutout, wherein the mask layer (4, 11) is produced by printing technology by means of a lacquer, so that a security element transfer material is obtained in which the security element layer composite in the region of the at least one cutout of the mask layer (4, 11) can be adhesively bonded to a value document substrate by the action of pressure and possibly heat by means of the adhesive layer (3, 9) and can then be detached from the carrier substrate (1, 7), wherein, in the region outside the at least one cutout of the mask layer (4, 11), the security element layer composite is prevented from adhering to the value document substrate and a subsequent detachment of the security element layer composite from the carrier substrate (1, 7).

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