DE102013201945A1 - Security feature for a value or security product and method of making the security feature - Google Patents

Abstract

The novel security feature 200 for a valuable or security product 100 is formed by at least one light-guiding structure 220 which passes through a product layer 105 having a front main surface 101 and a rear main surface 103. The at least one light-guiding structure 220 each has an end face for a light entrance 230 and an end face for a light exit 210. All end surfaces 210, 230 are located in the area of one of the main surfaces 101, 103. The light guide structure 220 is formed by a material strand section 250.

Description

The present invention relates to a security feature for a value or security product, for example a security or security document or security element, a value or security product having the security feature and a method for producing the security feature. A value or security document can be, for example, a means of payment, in particular a banknote, or another value document or else a personal document, in particular a passport. The documents can basically consist of paper, another fiber felt or cardboard or in principle also of an organic polymer, ceramic material, glass or of metal or contain this. Cards and card-shaped components of book-type documents may preferably be made of laminated polymer films. To test the authenticity and / or coding of information, these products have the security features according to the invention.

The security features used in the value or security products can only serve to prove the authenticity of the products, regardless of their nature or by their user. Such security features are, for example, guilloches, watermarks, embossing prints, tipping pictures, holograms, the special paper of banknotes and the like. Personalizing, for example personalizing, security features also contain in coded form or in plain text information about the type of document, about its owner and / or about an object to which the document is assigned. Such information may include a face image / portrait (for example in the form of a photograph) of the owner, his or her personal data such as name, date of birth, place of birth, signature, a personal identifier such as a membership number, or biometric data of the holder, such as fingerprints. Iris and retina detection. Another security feature that individualizes the document can be, for example, a serial number of the document or the chassis number of a motor vehicle to which the document is assigned.

In DD 301 115 A7 a tamper-proof paper is described which contains at least one type of regularly and / or arbitrarily designed, regularly and / or placed distributed or arranged special planchettes. This restricts or prevents the misuse of the special paper. In addition, it is stated in one exemplary embodiment that the substance-water mixture for producing the paper contains, in addition to the planchettes, UV-activatable mottling fibers. Furthermore, it is known that security papers contain security threads.

In Patent Abstracts of Japan too JP 2007-203568 a display is shown, which is formed from planar Lichtleitstrukturen. These light guide structures are provided with a diffraction grating or hologram having a surface relief, so that the light guided by the light guide structures is radiated from the diffraction grating or hologram.

In US 2004/0229022 A1 there is provided a security device having reflective layers and indicia having further layers which are layers in a laminate. Between the reflecting layers is a photoconductive layer. Holes can be introduced into the reflective layers. Light introduced through the holes is emitted.

In DE 10 2008 033 716 B3 there is disclosed a value or security document in which a light guiding structure for guiding light in a plane is substantially parallel to the top of the document. The light is decoupled from the light guide structures to local modifications and is thus visible on a surface. For example, light coupled in via the side edge of the document may exit at the surface via these modifications. The modifications are produced in the form of recesses in boundary layers, which delimit the light-guiding structures.

In CH 677 905 A5 a method for producing a multi-layered ID card is described. The card is made up of several film layers which are printed using different printing technologies. The cover films, the base films and other films are printed both digitally and by means of conventional printing processes. The base film is made of plastic and can be formed in two layers with fiber optics embedded therein. The end faces of the light guides are located on the card edges and allow the input or output coupling of light by means of appropriate readers. Thus, a personal arrangement of the optical fibers can be read by machine.

There is a constant need for novel, in particular individualizing security features that are secured against forgery and / or falsification and / or copy and that are easily recognizable, for example, to associate the information encoded with it to the nature of the value or security product of a person. Preferably, the security feature should be located in a secure counterfeiting and / or falsification and / or copy of the inner product layer. Of the The present invention is also based on the essential further object of providing a cost-effective, simple and quickly realizable, in particular individualizing, security feature. Another object of the present invention is to provide a security paper that is impossible or extremely difficult to falsify.

As far as in the description and in the claims of the present application, the term "value or security product", which may be in particular a security or security document or a security element is used, including in particular a means of payment, such as a banknote, or other value document such as a security, such as a check, or a visa page in a passport, bill of lading, tax stamp, postage stamp, ticket, or the like. It may, however, also be a passport, identity card, driver's license or other ID card or access control card, vehicle registration document, vehicle registration document, visa, check, bank, credit or cash card, customer card, health card, chip card, company ID , Proof of Entitlement, Membership Card, gift or shopping voucher or other proof of eligibility, a tokens, adhesive tag (for example, for product security) or any other such document. A product according to the invention may also be a security element, for example a sticker, label or the like, which has the security feature according to the invention and which can be permanently connected to a precursor of a value and / or security document in order to form the value and / or security document (transfer member). The product may be, for example, a smart card. The security or security document may be in a banknote format or in the ID 1, ID 2, ID 3 format or any other format, such as a booklet or brochure form, such as a passport-like item. A value or security product can also be a laminate

be made of several document layers, the register-accurate under heat and under increased pressure are connected flat. These products should meet the standardized requirements, for example ISO 10373 . ISO / IEC 7810 . ISO 14443 , The product layers consist, for example, of a carrier material which is suitable for lamination.

The value or security product is preferably formed from a fiber felt, for example from paper or cardboard. For the production of these materials in particular a fiber mass, especially of cotton, wood, rags, flax, jute, straw or the like is used. Furthermore, the value or security product can also be produced from other fiber materials, for example from mineral fibers, such as spun glass or rock wool, animal fibers, such as wool, leather or silk, or from polymer fibers or from mixtures of these materials. However, it can also be formed from a non-fibrous material, in particular from polymer, glass, metal or ceramic. The polymer of the fibrous or non-fibrous material may be selected from a group comprising polycarbonate (PC), especially bisphenol A polycarbonate, polyethylene terephthalate (PET), their derivatives such as glycol modified PET (PETG), polyethylene naphthalate (PEN), polyvinyl chloride (PEN). PVC), polyvinyl butyral (PVB), polymethyl methacrylate (PMMA), polyimide (PI), polyvinyl alcohol (PVA), polystyrene (PS), polyvinylphenol (PVP), polypropylene (PP), polyethylene (PE), thermoplastic elastomers (TPE), in particular thermoplastic polyurethane (TPU), acrylonitrile-butadiene-styrene copolymer (ABS) and their derivatives. Preferred polymers are PC and PC / TPU / PC. The polymers may be either filled or unfilled. In the latter case they are preferably transparent or translucent. If the polymers are filled, they are opaque. The product can be made of several of the aforementioned materials.

Insofar as the term "security feature" is mentioned in the description and in the claims of the present application, this is to be understood as a feature which preferably causes an optical impression which can be recognized by means of optical recognition methods. The visual impression is generated by light emission in the form of an optically perceptible design. This design preferably includes an individualizing information. The security feature may be configured to be directly perceived by a user, or it may be a machine-readable feature. In the latter case, the security feature is detected by means of, for example, electromagnetic radiation, spatially resolved receiving device and perceived by a viewer or evaluated by means of a device provided for this purpose. The security feature can be manufactured as part of a value or security document or as a separate product (security element). The latter can be glued to the document, for example. The security feature will generally only occupy part of the surface of the document.

According to a first aspect of the present invention, the objects are achieved by a security feature for a value or security product. This security feature is formed by at least one Lichtleitstruktur that at least partially passes through a product layer. This can do that Already make value or security product itself or just be a part of the value or security product. The product layer has a front and a rear main surface. The at least one light guide structure has in each case a first end face for a light entrance and a second end face for a light exit. All end faces of the at least one light guide structure are located in the region of one of the main surfaces. The light guiding structure is formed by a material strand section.

According to a second aspect of the present invention, the objects are also achieved by the value or security product having at least one inventive security feature.

• (a) Ausbilden eines eine vordere und eine hintere Hauptfläche aufweisenden Filmes eines zur Bildung der Produktlage geeigneten Vormaterials;
• (b) Einbringen eines Materialstranges in den Film des Vormaterials, sodass mindestens ein erster Abschnitt des Materialstranges innerhalb des Filmes des Vormaterials und mindestens ein zweiter Abschnitt des Materialstranges außerhalb des Filmes des Vormaterials verlaufen und sodass der Materialstrang zwischen dem mindestens einen ersten Abschnitt und dem mindestens einen zweiten Abschnitt durch mindestens eine der Hauptflächen des Filmes hindurchtritt;
• (c) Umwandeln des Filmes des Vormaterials unter Bildung der Produktlage, wobei der Materialstrang für die Bildung mindestens einer Lichtleitstruktur in der Produktlage fixiert wird; und
• (d) Entfernen des mindestens einen außerhalb der Produktlage verlaufenden zweiten Abschnittes des Materialstranges, beispielsweise durch Abscheren, sodass die mindestens eine Lichtleitstruktur in Form des mindestens einen zweiten Abschnittes des Materialstranges entsteht.

According to a third aspect of the present invention, the objects are also achieved by a method for producing the security feature. This process comprises the following process steps:

• (A) forming a front and a back main surface having a film of a suitable material for forming the product layer;
• (B) introducing a strand of material in the film of the starting material, so that at least a first portion of the material strand within the film of the starting material and at least a second portion of the material strand outside of the film of the starting material and run so that the strand of material between the at least one first portion and the at least a second portion passes through at least one of the major surfaces of the film;
• (c) converting the film of the primary material to form the product layer, wherein the strand of material for the formation of at least one Lichtleitstruktur is fixed in the product layer; and
• (d) removing the at least one second section of the material strand running outside the product layer, for example by shearing, so that the at least one light guide structure is formed in the form of the at least one second section of the material strand.

By forming the light guide structure in the form of a material strand section, it is firstly very easy to form the light guide structure in the product layer, so that the production of the product layer with the light guide structures can be made extremely simple and cost-effective. In particular, no elaborate production methods, such as laser ablation, such as in DE 10 2008 033 716 B3 , required. Furthermore, it is also advantageous to arrange the end faces of the light guide structures in the region of one or both main surfaces of the product layer, because the value or security product thereby receives a design serving as a security feature, which can be easily perceived by a viewer. In addition, the arrangement of the end faces of the light guide structures on the surfaces of the product layer also allows a variety of design options that are not given in their arrangement on the side edge. With the in CH 677 905 A5 Accordingly, there are only a few spatial possibilities of the arrangement for the light input and output. In addition, verification in this case is usefully made by machine; Verification with the naked eye is not readily feasible.

In a first embodiment variant of the present invention, a first end face of the at least one light guide structure, for example for light entry, in the region of a first main surface of the product layer and a second end face of this light guide structure, for example for the light exit, can be in the region of a second main surface of the product layer ( two-sided embodiment, see-through feature). In a second embodiment variant, both end faces of the at least one light guide structure can be located in the region of only one of the two main surfaces of the product layer (one-sided embodiment). Thus, on one side of the valuable or security product, electromagnetic radiation entering the optical waveguide structure can emerge again either on the opposite side or on the same side. The electromagnetic radiation used is preferably radiation in the visible spectral range, i. in a spectral range from about 400 nm to about 750 nm. It may alternatively be UV radiation or IR radiation. It is essential that the electromagnetic radiation used in the light guide structures is not significantly absorbed.

By means of the light guide structures, an optically perceptible security feature is created whose imitation or counterfeiting is extremely complex. This safety feature consists in the delocalized electromagnetic radiation in the light guide structures being delocalized into the light guide structures via an end face in the region of one of the main surfaces of the product layer to the opposite end face in the region of one of the main surfaces of the product layer, where it exits again. The incoming electromagnetic radiation comes either from daylight or from an artificial light source, such as an LED. The electromagnetic radiation enters, for example, from the front or from the back of the product layer in the Lichtleitstrukturen. At the end faces of the light guide structures, at which electromagnetic radiation emerges, a viewer can perceive the exiting electromagnetic radiation. The same applies to a machine reader. The assignment made in this patent application of the end faces as Light entrance or light exit surfaces results in the application when light falls on the faces and enters there and exits at the other end faces again.

In a preferred embodiment of the present invention, the at least one light guide structure is formed from a polymer material. The polymer may be one of the polymer materials which are also suitable for the formation of the value or security product itself and from which, for example, the product layer may also be formed. The strand of material may be supplied as a thread, yarn, fiber or the like from a dispenser to the precursor. For example, the material strand may be stored. In this case, the dispenser is for example a dispenser. Or, the strand can be made, such as by spinning, extruding, or other strand forming technique, just prior to incorporation into the starting material. In this case, the dispenser is, for example, an extrusion nozzle or a spinneret. Alternatively, the Lichtleitstruktur may also be present as a glass fiber. This is preferably stored and fed from the supply to the precursor.

In a further preferred development of the present invention, the light guide structures in the form of material strand sections are formed by a transparent material having a first refractive index and enclosed by a second material having a second refractive index which is lower than the first refractive index. The second material may be transparent, translucent or opaque. The refractive indices are respectively defined with respect to the wavelength of the electromagnetic radiation used. As a result of the configuration formed by a material strand section and the second material surrounding it, the electromagnetic radiation in the light guide structures is passed on virtually without attenuation by totally reflecting the radiation at the interface between the material strand section and the second material. For this purpose, the second material can be formed in any desired shape, as long as it encloses the material strand almost completely (over> 90% of the surface of the material strand section), better still completely. For this purpose, the second material may be formed, for example, in the manner of a jacket or an envelope, for example in the form of a tube. In principle, however, the second material may also represent an embedding material for the material strand section, for example by the product layer itself forming the second material surrounding the light guide structure, provided that the product layer is formed by a homogeneous medium. Air is particularly suitable as a second material because of its very low refractive index. In the case of a fiber felt for the product layer forming potting material, air eventually fills in spaces between the fibers and forms the second material.

The second material surrounding the material strand section may preferably be formed from a polymer, in particular from one of the polymers which are also indicated for the formation of the valuable or security product.

In a further preferred development of the present invention, the at least one light-conducting structure is held in the product position by means of an adhesion layer. Preferably, the adhesion layer is formed by a hot-melt adhesive. For example, the hot-melt adhesive has a softening temperature of 50 to 200 ° C, preferably from 80 to 120 ° C, on. After converting the film from the primary material to the (solidified) product layer, the hot-melt adhesive unfolds its adhesive properties and anchors the optical fiber structure in the product layer as the product layer is heated along with the optical fiber structure, thereby softening the hot-melt adhesive. Alternatively, the adhesion layer can also be formed by a UV-curable adhesive. For curing and for bonding the Lichtleitstruktur with the material of the product layer, this is preferably exposed in this case after their production UV radiation to cure the adhesive. The adhesion layer preferably has a second refractive index at one of the wavelengths of the electromagnetic radiation used, which is smaller than the first refractive index of the material strand section. Thus, the adhesion layer forms the second material surrounding the material strand section, which causes total reflection of the electromagnetic radiation in the material strand section.

In a further preferred development of the present invention, the at least one light guide structure contains at least one material absorbing in the visible spectral range, so that white radiation which has entered the light guide structure appears colored. An absorbing material of the light guiding structure can be provided in particular by one or more absorptive dyes which are introduced into the material of the light guiding structure. For example, either a single absorptive dye with a given absorption and reflectance spectrum or a mixture of several absorptive dyes can be used, each having an individual absorption and remission spectrum and in the mixture have a different absorption and remission spectrum of the individual absorptive dyes, which results subtractive from the spectra of the individual absorptive dyes. The absorptive dyes may be inorganic or organic compounds. Organic absorptive Dyes may typically be azo compounds. Although the absorptive dyes absorb electromagnetic radiation conducted through the optical waveguide structure, they do not scatter or substantially scatter them, so that the radiation in the optical waveguide structures is preferably not substantially or not substantially attenuated.

In a further preferred development of the present invention, the at least one optical waveguide structure additionally or alternatively to the absorptive dyes contains at least one luminescent material in the visible spectral range, such that the optical waveguide structure luminesces when irradiated with excitation radiation (photoluminescence, both Stokes and anti-Stokes -Shift). In principle, of course, other luminescence mechanisms are also conceivable, such as electroluminescence, the luminescent structure luminescing in the light guide structure when generating an electrostatic field. The excitation radiation for the luminescence is preferably UV radiation (UVA, UVB or UVC radiation), but may also be IR or visible radiation. A luminescent material of the optical waveguide structure can in particular be provided by one or more luminescent substances which are introduced into the material of the optical waveguide structure. The at least one luminescent substance can, for example, luminesce broadband or narrow band in the visible spectral range. If the spectral distribution of the luminescence in this area is not uniform, the emitted light is also colored. The luminescent substance, like the absorptive dye, may be organic or inorganic. Typical luminescent substances are, for example, in US 3,474,027 A . DE 198 60 093 A and DE 10 2007 035 592 A1 , the disclosure of which is incorporated in the present application. These are host lattices doped with rare earths as luminophores, in particular substances doped with terbium, cerium and / or europium, for example oxysulfides and oxynitrides. In principle, it is also possible to use calcium phosphates, zinc silicates, strontium phosphates, alkaline earth silicates, silicates and rare earth aluminates, alkaline earth metal tungstates, zinc oxides, zinc sulfides and rare earth oxides, which are denoted by Eu ²⁺ , Eu ³⁺ , Sb ³⁺ , Mn ²⁺ , Ag ⁺ , Cu ⁺ , Sn ²⁺ or Tb ³⁺ . The pigments formed herewith can additionally be coated with organic substances in order to increase the quantum yield of the luminescence. Furthermore, quantum dots can also be used, ie semiconductor particles whose size is in the nm range, for example based on CdS. Furthermore, organic luminescent substances are also usable, such as rhodamine 6G or fluorescein. The luminescent substances do not scatter the electromagnetic radiation transmitted through the optical waveguide structure or do not significantly, so that the radiation in the optical waveguide structures is preferably not appreciably or not substantially attenuated.

The absorptive dyes and the luminescent substances can be used individually or combined in a light-guiding structure. If several optical waveguide structures are present, they may contain an absorptive dye and / or a luminescent substance or different absorptive dyes and / or luminescent substances. In the latter case, the distribution of the color (including the specific absorption in spectral regions other than in the visible spectral range) and / or the spectral difference of the luminescence between the optical waveguides can represent another security feature that can also encode information.

The light guide structures can be located in any position in the product layer. The light guiding structures are preferably by short, for example from 100 .mu.m to 10 mm, more preferably from 200 .mu.m to 5 mm, even more preferably from 300 .mu.m to 2 mm, even more preferably from 400 .mu.m to 1000 .mu.m and most preferably from 500 .mu.m formed up to 800 microns, long material strand sections, which most preferably do not branch, but extend exclusively from a light entrance end face to a light exit end face. The material strand sections preferably have a round, very particularly preferably a circular, cross-section. The diameter of such material strand sections may, for example, be in the range from 10 μm to 500 μm, preferably from 30 μm to 150 μm and most preferably from 40 to 100 μm. The cross section may also be oval, quadrangular, in particular square or rectangular, or polygonal. If it is rectangular, the material strand sections can be flat strips. The cross section of the material strand sections can be in particular in the range of 1600 to 10,000 μm ² . The material strand sections may be arranged regularly or irregularly in the product layer. The material strand sections can traverse the product layer (see-through feature), for example in a straight track in a direction perpendicular to their main surfaces, so that in each case one end face of the material strand sections lies in the region of one of the two main surfaces. However, the material strand sections can also pass through the product layer in a curved track, which connects the two main surfaces of the product layer. In the latter cases, the end faces are therefore arranged, when viewing the product layer, either exactly perpendicular to the main surfaces one above the other or offset from one another.

In a particularly preferred development of the present invention, at least two optical waveguide structures are in one product layer Production direction of the material of the product layer arranged one behind the other running. For example, the material of the product layer may be a fiber felt material, in particular a paper. In this case, the paper is typically produced in a rotary screen paper machine as a continuous paper web. During production, the production process results in a production direction in which the paper web is produced. In the same way, it is also possible to produce a continuous polymer film web in an extruder, which likewise results in a production direction in which the at least two light guiding structures are arranged running one behind the other. In the production of the continuous web, the light guiding structures are produced in the resulting continuous web. In this case, the material strand sections of these light guide structures preferably extend in each case from one main surface to another and pass through the product layer for this purpose. Alternatively, the material strand sections can only partially pass through the product layer, so that all end faces are located only in the region of one of the main surfaces. If a plurality of such arranged Lichtleitstrukturen are arranged in these variants, this results in lines on the product layer lying end faces of the material strand sections. In still further embodiments, the end faces of the material strand sections may be arranged in a predetermined dot pattern on one or both main surfaces of the product layer. The dot pattern can consist of a somewhat shaped distribution of the end faces on one or both main surfaces of the product layer, which for example give a self-contained representation, in particular an image, picture element, character, above all an alphanumeric character, a symbol, coat of arms, a line or another simple geometric shape, such as a formula, or the like. In this respect, the dot pattern may contain information, for example the denomination of the banknote provided therewith, and thus in particular also individualizing information. The dot pattern is preferably formed exclusively by the exit surfaces of the material strand sections.

In a further preferred development of the present invention, the product layer is formed at least substantially from a fiber felt. For example, the fiber felt fabric may be formed from paper or paperboard or from another fiber mass. In particular, vegetable fibers, especially fibers of cotton, wood, rags, flax, jute, straw or the like are used. In principle, mineral fibers such as spun glass or rock wool, animal fibers, such as wool, leather or silk, or polymer fibers in question.

For the production of a product layer provided with light guiding structures in the form of material strand sections, a precursor is first formed from a starting material, for example a film of fibrous materials which are skimmed off from a paper fiber slurry by means of a round or wire sieve, or a soft polymer film in an extruder, where the film forms. The product layer is then formed from the film by conversion, for example by dewatering the fiber film, so that the fiber felt thickens, or the polymer film solidifies.

Prior to this conversion, the material strand is introduced into the precursor, for example, the fibrous film located on the sieve or a still soft polymer film, for example by pressing the material strand into the precursor. For this purpose, preferably a material strand is used, which has a multiple of the length of the material strand sections contained in the finished product layer. This material strand can be produced, for example, immediately before introduction into the precursor by means of an extrusion die, so that the material of the strand is still bendable and soft. In order to introduce the material strand into the precursor, so that it is predominantly within the precursor, mechanical means can be used which selectively push the material strand locally, ie at defined locations along the strand of material, into the material of the precursor and optionally through it , For example, a profiling or embossing means, for example a comb, can be used, which pushes the material strand into and out of the material by means of its teeth, the intervening sections of the material strand extending at least partially within the preliminary product. As an alternative to a comb, it is also possible to use a contouring roller, by means of which the leading edge of the material strand is selectively penetrated into the precursor and / or pressed through it. With a guide of the material strand along one of the major surfaces of the precursor and application of a contouring roller with uniform teeth a wavy strand is obtained, which occurs on the voltage applied to the contouring roller side of the film at regular intervals through the main surface to the outside and otherwise either completely runs within the film or sections within the film and partially exits from the film on the opposite side to the contouring roller. The contouring roller may also have a non-uniformly arranged toothing with not equiangularly arranged nose strips, so that the material strand is pressed in unevenly spaced locations in the film. Alternatively, it is also possible to use a planar stamp with embossing elements which are evenly or non-uniformly spaced from each other, with whose profiling the material strand is pressed into the film. The profiling This stamp can be designed in the form of a pattern, so that the end faces are arranged in the form of this pattern, in particular if a plurality of strands of material are introduced in a side-by-side manner.

When converting the precursor into the product layer, the material strand is fixed in position in the starting material. After conversion, the outer sections of the material strand are removed, for example by shearing, so that isolated material strand sections of the light guide structures form within the product layer. Their end surfaces are formed when removing the outer sections of the material strand, for example as cutting or shear surfaces, preferably flush with the corresponding main surface of the product layer. In particular, when shearing with a tool suitable for this end surfaces are generated, which are substantially aligned with the main surfaces. The projecting sections of the material strand can be sheared off, for example, with doctor blades which operate at a shallow angle (<45 °, preferably <25 °, even more preferably <20 °) against the surface of the product layer.

The above explanation for the production of the optical waveguide structures applies mutatis mutandis to the introduction of several strands of material in the Vormaterialfilm, the deformation and solidification of these strands of material and the removal of the outer portions of these strands, resulting in a variety of Lichtleitstrukturen. From each of the strands of material at least one Lichtleitstruktur is formed.

It is particularly preferred if a fiber slurry used for the production of banknotes or other security or security papers, for example a slurry of paper fibers, in particular cotton fibers, is fed to a multibox paper machine for producing a continuous paper web (by scooping the slurry). As a result, a fiber film is formed. During the removal of the liquid, in particular of water, from the paper pulp adhering to the round or wire mesh, a strand of material or even several strands of material guided in parallel, for example, parallel to the running direction of the paper material in the paper machine, is fed into the film of the pulp adhering to the sieve , For this purpose, for example, a polymer is dispensed from an extrusion nozzle, or an already produced material strand provided by a dispenser, for example a glass fiber. Other donors are also possible. The material strand is preferably enveloped by a hot-melt adhesive, which has a lower refractive index than the material of the material strand. By means of a spatially subordinate contouring roller or other profiling or embossing means, the material strand is punctually inserted at regular intervals in the paper pulp and optionally pushed through it. With appropriate adjustment of the manufacturing parameters (paper machine speed, feed rate of the material strand, positioning of the contouring roller over the surface of the screen) portions of the material strand remain between depressed sections above the pulp and other portions below the pulp so that they sag after the paper has dried protruding either side outside, or the material strand is completely pressed into the paper pulp, so that only the rearwardly projecting portions protrude outward. Alternatively, the material strand can also only partially be pressed into the paper pulp, in which case portions of the strand project above the pulp fiber pulp. Of course, this procedure is also possible with other fiber felts or with molten polymer or other materials. The hot-melt adhesive is then melted in the dryer section of the paper machine so that the strand of material is fixed in the paper. Thereafter, the protruding portions of the material strand are sheared off by means of sharp knives. As a result, small portions of the strand or strands of material remain in the paper material, which are located entirely within the material and whose end faces are in the area of or on the main surfaces of the paper. When drying the Faserbreifilmes the Faserfilzstoff, which forms the product layer forms. If necessary, the material must be cut to the required size.

If the product layer is not produced as a paper layer or in the form of another fiber felt, but in the form of a polymer film, the polymer material used for this purpose can be converted into the film form, for example by extrusion. The strand of material in this case is provided as described above, for example by extruding from a die just prior to introduction into the still soft polymer or by providing a stockpiled strand of material, for example a glass fiber. The material strand is introduced or inserted into the still soft polymer material and then deformed by pressing into the polymer material. Finally, protruding portions of the strand of material are removed.

Optionally, the material strand is wrapped in the production variants described above with an adhesive, in particular a hot-melt adhesive. The adhesive is after the introduction of the material strand into the starting material, deformation of the material strand and during or after the conversion of the starting material, so that the product layer is formed, UV cured if it is a UV curable adhesive, or heated so that it softens if it is a hot melt adhesive, so that the material strand firmly bonds to the surrounding material of the product layer.

The material strand can also be initially stored in the embodiments described above for the production of the product layer and, for example, kept in a roll. To produce the product layer, the material strand can be fed to the precursor, for example, from a dispenser and deformed therein.

The material of the product layer is preferably opaque or alternatively transparent or translucent, the material in the latter cases partially absorbing the electromagnetic radiation used. In these cases, the electromagnetic radiation emitted by the optical waveguides is visually easily recognizable because a contrast of the light exit surfaces of the optical waveguides to the surrounding material results.

The product layer into which the light guiding structures are incorporated may be part of the valuable or security product or may itself form the value or security product. For example, it is a single product layer that is stacked with other product layers into a stack and then bonded to these other layers, for example, in a lamination process, to form the security or security document. Alternatively or additionally, the product layer provided with the light-guiding structures can additionally be coated with a protective lacquer, so that the security feature lies inside the finished product and thus can not be readily manipulated by a third party. In these cases, outer layers and / or layers which cover the product layer provided with the light guide structures are to be made transparent or at least translucent so that the optical perception content generated by the light guide structures can be detected by a viewer or a machine.

For the verification of the value or security product this can either be readily considered by a viewer under daylight conditions or under illumination with artificial light by the light falls, for example, on the back of the product and there enters via the end faces in the material strand sections of the light guide structures. The viewer looks at the opposite side of the value or security product, where the other end faces of the light guide structures are located. The transmitted light is visible at these faces. With a corresponding spatial arrangement of the light exit surfaces of the light guide structures, the viewer can use this arrangement as a verification feature. If the optical waveguides only partially cross the product layer and their end faces lie in the region of only one major surface of the product layer, mechanical verification is advantageous, since in this case a spatially limited irradiation in the region of the light entry surfaces of the optical waveguides is required and at the same time the spatially limited radiation of passed electromagnetic radiation must be detected by the light exit surfaces. For example, the value or security product can be scanned successively, wherein the light exit surfaces of the light guide structures are detected gradually.

The security and / or security product can have, in addition to the security feature according to the invention, further security features, for example guilloches, micro-writing, holograms, kinegrams and the like. Furthermore, a value or security document may also comprise electronic components, for example an RFID circuit with antenna and RFID microchip, electronic display elements, LEDs, touch-sensitive sensors and the like. For example, the electronic components may be hidden between two opaque layers of the document.

For a more detailed explanation of the present invention, the figures described below, which illustrate the invention by way of example, without affecting the scope of the invention serve:

1 shows a banknote with the security feature according to the invention in plan view in a schematic representation in a first embodiment;

2 shows two variants of the banknote crossing light guide structure in cross section in a schematic representation; (A) with both located on one of the main surfaces of the bill end faces of the Lichtleitstruktur; (B) with located on each one of the main surfaces of the bill end faces of the Lichtleitstruktur; (C) is a schematic sectional view through a strand of material with a hot-melt adhesive sheath;

3 shows a banknote with the security feature according to the invention in plan view in a schematic representation in a second embodiment;

4 shows a method for introducing a material strand into a Papierfaserbrei skimmed on a round screen of a paper machine, the shaping of the material strand and the Shearing one-sided outboard sections of the material strand in a side view in a schematic representation in a first embodiment;

5 shows a method for introducing a material strand into a paper pulp skimmed on a round screen of a paper machine and shearing both sides of external sections of the material strand in a side view in a schematic representation in a second embodiment;

6 shows an arrangement for verifying a banknote having a security feature according to the invention; (A) in a perspective schematic representation; (B) in a schematic sectional view.

In the figures, like reference numerals designate elements having the same function or elements.

In the 1 illustrated banknote 100 is made of a fiber felt fabric. The paper of this material is recovered in a conventional manner from a fiber-water slurry in a paper machine with a round screen as continuous material. The fiber material is preferably made of cotton. The banknote forms a product layer according to the invention 105 by separating, for example, cutting or punching, from a paper web 500 ( 4 . 5 ) is formed.

The banknote 100 has a front major surface 101 and a rear major surface 103 on ( 2A . 2 B ). In the left border area 102 the banknote is a watermark 130 that was created during the papermaking process in a conventional manner. Further, on the front major surface some other security features are shown, namely two printed symbols 110 in the form of the denomination of the banknote ("50"), for example by means of a color containing an optically variable pigment, and a hologram 120 in the form of a transfer element. Furthermore, the banknote has further security features, such as guilloche (not shown).

The security feature according to the invention 200 is through several optical fiber structures 220 formed, their light exit surfaces 210 on the front main surface 101 the banknote 100 or the product location 105 are located. These light guide structures extend, for example, through the entire banknote body to the rear main area 103 , There they end and form light entry surfaces 230 which are aligned with the rear major surface of the banknote ( 2 B ). When viewing the banknote in the backlight or at least at a light incident on the rear main surface of the banknote, so that there light can enter through the light entry surfaces in the Lichtleitstrukturen, the light exit surfaces light up on the front main surface of the banknote. The light exit surfaces are arranged in such a way that together they also reflect the denomination of the banknote ("50").

The light guiding structures 220 are through transparent material strand sections 250 formed the material of the banknote 100 completely traverse and their light entry surface 230 flush with the rear main surface 103 and their light exit surface 210 flush with the front main surface 101 to lock. In 2 B an example of a material strand section running inside the banknote body is shown. Between the rear main surface and the front main surface, the material strand section runs on a tortuous path through the banknote body. As a result, the light entrance and the light exit surfaces are not superimposed. The material strand section is formed by a polymer, for example polymethyl methacrylate (PMMA). Alternatively, the material strand section may also be formed by a glass fiber section.

Deviating from the configuration of the light guide structure 220 with both sides on the main surfaces 101 . 103 the banknote 100 ending faces (light entry surface 230 and light exit surface 210 ) shows 2A a Lichtleitstruktur whose two end faces are located on the same main surface of the banknote.

The material strand section 250 is on the outside of a hot-melt adhesive material 260 surround ( 2A . 2 B . 2C ). This material has a refractive index which is less than that of the material of the material strand section. In the light guide structure 220 The light that has entered is therefore totally reflected during the propagation at the interface with the hot-melt adhesive. As a result, a low degree of attenuation for the propagation of light in the light guide structure is achieved. Furthermore, the hot-melt adhesive jacket serves for the material strand section in the material of the banknote 100 firmly anchored so that it can not be removed. For this purpose, the material of the banknote or the product location 105 heated to dryness after dewatering in the paper machine, so that the hot-melt adhesive softens and combines with the banknote material. Therefore, the adhesive forms both an adhesion layer and a total reflection permitting second layer having a refractive index lower than the refractive index of the material of the strand section.

It is possible that the material strand sections 250 contain absorbing and / or luminescent substances, so that appropriate physical properties for the light guiding structures 220 result. If absorbers in the strand sections cause the material of the strand to have a color, but without unduly obstructing the passage of light, the light exit surfaces may 210 even when illuminated with white light to be perceived in color. Several sections of material strand can be colored differently. This results in a variety of design options of light guiding structures of a security feature. If luminescent substances are contained in the material strand sections, the light exit surfaces luminesce colored or white if the luminescence lies in the visible spectral range.

A second embodiment of the banknote 100 is in 3 shown. Apart from the already discussed with respect to the first embodiment further security features 110 . 120 . 130 the banknote in this embodiment also has a security feature according to the invention 200 on, with the light exit surfaces 210 are arranged in this case in three mutually parallel vertical rows and spaced apart from each other within the rows. The pattern of the light exit surfaces may, for example, indicate the denomination or the place of production of the banknote in coded form. The light guiding structures 220 , whose light exit surfaces on the front main surface 101 are visible within the banknote body respectively between the front major surface and the rear major surface. All light guiding structures of a row together form a course extending from a lower edge 107 to an upper edge 106 the banknote extends. They are preferably in the running direction (production direction H) of the for the production of the banknote paper 500 strainer used aligned in the paper machine or the manufacturing direction in extruding a polymer film. This allows a simple production of multiple light guide structures in a defined arrangement to each other. Each light exit surface on the front main surface of the banknote is a corresponding light entry surface 230 on the back main surface 103 assigned to the banknote.

In 4 is the manufacturing process for one with Lichtleitstrukturen 220 provided fiber felt material in a first embodiment shown schematically. The aqueous pulp is conventionally in the figure coming from the left in the direction of production H by means of a round screen 300 a paper machine (which rotates in the direction of manufacture) drawn from a slurry of the fiber material, such as cotton fibers, which is a film 310 training on the round screen. This film is dried there by removing water and results in an endless paper web 500 ,

In the not yet dried state of the paper fiber film 310 becomes a strand of material consisting of a polymer 320 by means of an extrusion nozzle 330 generated and introduced into the paper fiber film. The polymer may be, for example, polyamide (PA) or polycarbonate (PC), which is injected into the paper pulp slurry in the molten state. The polymer thread produced may additionally comprise a sheath of a hot-melt adhesive. For this purpose, the extrusion nozzle has a nozzle opening for the material strand and an annular gap surrounding the nozzle opening for the hot-melt adhesive material, so that the coated material strand is produced in an extrusion step (not shown). In the paper pulp, the polymer material gradually cools and becomes solid.

Immediately behind the injection point of the polymer thread in the paper fiber film 310 there are two contouring rollers arranged one behind the other 350 . 360 with equiangular profile webs 370 which press the polymer thread locally into the paper pulp. As a result, a wave-shaped formation of the polymer thread is achieved, the first thread sections 291 are within the paper fiber film, and wherein lying in front thread loops 270 in second thread sections 292 sticking out of the paper material.

In the dryer section of the paper machine that runs from the round screen 300 entrained paper material on a doctor blade 380 along the front of the main surface 101 protruding thread loops 270 shears flush with the surface of the paper stock. In this case, overhead faces (light entrance surface 230 and light exit surface 210 ) of the material strand sections now separated from each other 250 or light guide structures 220 educated. The material strand sections each extend between two on the same front major surface of the paper web 500 arranged end faces. This corresponds to the embodiment according to FIG 2A (one-sided variant).

In 4 is not shown that it is not only possible to integrate a single such polymer thread in the direction H of the paper machine in the material but a plurality of parallel polymer threads, which in the illustration of 4 are guided one behind the other and parallel to each other. As a result, a plurality of parallel rows of light guide structures 220 formed next to each other. This leads to the embodiment according to 3 ,

In 5 is the manufacturing process for one with Lichtleitstrukturen 220 provided fiber felt material in a second embodiment shown schematically. As in the first embodiment, the aqueous pulp in a conventional manner in a direction of production H by means of a round screen 300 a paper machine (not shown) made of a slurry of the fiber material, such as cotton fibers, scooped out, wherein a film 310 on the round screen, which is dried there by removing water and an endless paper web 500 results. Also in this case, an existing example of PA or PC material strand by means of an extrusion die 330 generated and introduced into the paper fiber film. The polymer thread produced can in turn additionally comprise a sheath made of a hot-melt adhesive (not shown). In 5 not shown is an arrangement of two successive contouring rollers, the polymer thread at regular intervals in the pulp mass and partially push out in this case by this again. This will make the in 5 shown wavy formation of the polymer thread achieved. In this case, not only the front thread loops protrude 270 but also thread loops 280 at the rear main surface 103 in second sections 292 out of the paper material. The polymer thread is in the first thread sections 291 within the movie.

In the dryer section of the paper machine that runs from the round screen 300 entrained paper material on both sides of the paper web 500 adjacent doctor blades 380 . 390 along which are the protruding front and rear thread loops 270 . 280 flush with the surfaces 101 . 103 shear the paper web. In this case, front end surfaces (light exit surfaces 210 ) and rear end surfaces (light entry surfaces 230 ) of the material strand sections now separated from each other 250 or light guide structures 220 educated. The material strand sections or light guide structures each extend between two end faces arranged on different main surfaces of the paper web. This corresponds to the embodiment according to FIG 2 B (two-sided variant).

In 6A . 6B is an arrangement for machine verifying a banknote 100 represented, the one-sided and juxtaposed light entry surfaces 230 and light exit surfaces 210 of the security element 200 has (corresponding 2A ), wherein the strand of material in the paper in a to the embodiment of 3 rotated by 90 °, namely from right to left or vice versa. The arrangement has an excitation and read-out module 400 on, which extends across the banknote. The longitudinally extending excitation and read-out module is by a light source 410 with a plurality of in the longitudinal direction successively arranged LED 430 as well as with a detection element 420 equipped. The detection element has photodiodes arranged one behind the other in the longitudinal extension 440 on, which can detect a light incidence. The banknote is traversed under this module in the direction P indicated by the arrow, so that the respectively adjacent pairs of light entry surfaces 230 and light exit surfaces 210 the light guiding structures 220 be run over. It falls light from the LED 430 via the light entry surfaces in the Lichtleitstrukturen and passes through the light exit surfaces to the photodiodes 440 , When passing through the module, therefore, this module detects the presence of the light guiding structures in the banknote, their position being on the front main surface 101 the banknote can be determined by the position of the banknote are determined relative to the module and by the addressed photodiode upon detection of a Lichtleitstruktur.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DD 301115 A7 [0003]
• JP 2007-203568 [0004]
• US 2004/0229022 A1 [0005]
• DE 102008033716 B3 [0006, 0016]
• CH 677905 A5 [0007, 0016]
• US 3474027A [0024]
• DE 19860093A [0024]
• DE 102007035592 A1 [0024]

Cited non-patent literature

• ISO 10373 [0010]
• ISO / IEC 7810 [0010]
• ISO 14443 [0010]

Claims (13)

Security feature ( 200 ) for a value or security product ( 100 ), formed by at least one light guide structure ( 220 ), which has a front main surface ( 101 ) and a rear main surface ( 103 ) product situation ( 105 ), wherein the at least one light guiding structure ( 220 ) each have an end face for a light entry ( 230 ) and an end face for a light exit ( 210 ) and wherein all end faces ( 210 . 230 ) in the area of one of the main surfaces ( 101 . 103 ), characterized in that the light guiding structure ( 220 ) through a strand of material ( 250 ) is formed. Security feature ( 200 ) for a value or security product ( 100 ) according to claim 1, characterized in that the material strand section ( 250 ) is formed by a transparent material having a first refractive index and is enclosed by a second material having a second refractive index which is lower than the first refractive index. Security feature ( 200 ) for a value or security product ( 100 ) according to one of the preceding claims, characterized in that the at least one light guiding structure ( 220 ) is formed of a polymer material. Security feature ( 200 ) for a value or security product ( 100 ) according to one of the preceding claims, characterized in that the at least one light guiding structure ( 220 ) by means of an adhesion layer ( 260 ) in the product situation ( 105 ) is held. Security feature ( 200 ) for a value or security product ( 100 ) according to one of the preceding claims, characterized in that the adhesion layer ( 260 ) is formed by a hot-melt adhesive. Security feature ( 200 ) for a value or security product ( 100 ) according to one of the preceding claims, characterized in that the at least one light guiding structure ( 220 ) contains at least one material which absorbs in the visible spectral range and / or at least one material which luminesces in the visible spectral range. Security feature ( 200 ) for a value or security product ( 100 ) according to one of the preceding claims, characterized in that in the product layer ( 105 ) at least two light guiding structures ( 220 ) in a production direction (H) of the material of the product layer ( 105 ) are arranged running one behind the other. Security feature ( 200 ) for a value or security product ( 100 ) according to one of the preceding claims, characterized in that the product layer ( 105 ) is formed at least substantially of a fiber felt. Value or security product ( 100 ), having at least one security feature ( 200 ) according to one of claims 1 to 8. Method for producing the security feature ( 200 ) according to one of claims 1 to 8, comprising the following method steps: (a) forming a front main surface ( 101 ) and a rear main surface ( 103 ) ( 310 ) one for forming a product layer ( 105 ) suitable starting material; (b) introducing a material strand ( 320 ) in the movie ( 310 ) of the input material so that at least a first section ( 291 ) of the material strand ( 320 ) within the movie ( 310 ) of the input material and at least a second section ( 292 ) of the material strand ( 320 ) outside the movie ( 310 ) of the starting material and so that the material strand ( 320 ) between the at least one first section ( 291 ) and the at least one second section ( 292 ) through at least one of the major surfaces ( 101 . 103 ) of the film ( 310 ) passes through; (c) converting the film ( 310 ) of the starting material to form the product layer ( 105 ), wherein the strand of material ( 320 ) for the formation of at least one light guide structure ( 220 ) in the product situation ( 105 ) is fixed; and (d) removing the at least one outside the product layer ( 105 ) extending second section ( 292 ) of the material strand ( 320 ), so that the at least one light guiding structure ( 220 ) in the form of the at least one second section ( 292 ) of the material strand ( 250 ) arises. Method for producing the security feature ( 200 ) according to claim 10, characterized in that the starting material is a pulp containing a liquid and that the film ( 310 ) by removing the liquid to form the product layer ( 105 ) is converted. Method for producing the security feature ( 200 ) according to one of claims 10 and 11, characterized in that the material strand ( 250 ) by extruding a polymer material or by inserting a glass fiber into the film ( 310 ) of the starting material is introduced. Method for producing the security feature ( 200 ) according to claim 12, characterized in that the material strand ( 250 ) at the Introducing into the starting material is pressed locally into the starting material.

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