Abstract
An easily producible security feature according to the invention contains at least one luminescence device on and/or in a product carrier. Additionally, the security feature contains, in and/or on the product carrier, at least one absorptive spectral filter for luminescence radiation exiting from the at least one luminescence device, such that a color impression results both under illumination with visible radiation and under luminescence illumination conditions.
Claims
1. A security device, comprising: a product carrier; a security feature in and/or on said product carrier, said security feature including: at least one luminescence means and at least one absorptive spectral filter for filtering a luminescence radiation emitted by said at least one luminescence means; said at least one absorptive spectral filter being luminescent in a visible spectral range under excitation conditions for said at least one luminescence means; said at least one luminescence means and said at least one absorptive spectral filter forming a pattern with a plurality of pattern elements each formed by said at least one luminescence means and said at least one absorptive spectral filter means; and wherein luminescence pattern elements, formed by said at least one luminescence means, and absorptive pattern elements, formed by said at least one absorptive spectral filter means, are configured with equal size and disposed above one another in accurately aligned registration.
2. The security device according to claim 1, wherein said at least one luminescence means is configured to luminesce in the visible spectral range by excitation with UV radiation.
3. The security device according to claim 1, wherein at least one of said at least one absorptive spectral filter produces no luminescence radiation under irradiation.
4. The security device according to claim 1, wherein said at least one absorptive spectral filter is contained in at least one pattern formed with printing colors according to a CMYK color space.
5. The security device according to claim 1, wherein said luminescence pattern elements and said absorptive pattern elements are in each case arranged in direct contact with one another.
6. The security device according to claim 1, wherein said pattern elements are disposed in a pattern element layer containing both said at least one luminescence means and said at least one absorptive spectral filter.
7. The security device according to claim 1, wherein said at least one luminescence means forms a luminescence pattern and said at least one absorptive spectral filter forms an absorptive pattern and wherein the luminescence pattern and the absorptive pattern are in each case individualizing for a valuable and/or security product formed therewith.
8. The security device according to claim 1, wherein said at least one luminescence means forms a luminescence pattern and said at least one absorptive spectral filter forms an absorptive pattern and wherein the luminescence pattern and the absorptive pattern are formed by a single pattern layer which contains both said at least one luminescence means and said at least one absorptive spectral filter.
Description
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
(1) The figures described below serve for more detailed explanation of the invention.
(2) FIG. 1 shows a valuable and/or security document with a facial image of the document owner in a perspective view;
(3) FIG. 2 shows an arrangement for verification of the genuineness of the valuable and/or security document of FIG. 1 under illumination conditions with light in the visible spectral range (a); under illumination conditions with UV light (b);
(4) FIG. 3 shows embodiments of the arrangement of absorptive and luminescence pattern elements in schematic sectional views: (a) with luminescence pattern elements located on top; (b) with absorptive pattern elements located on top; (c) with pattern elements which contain at the same time at least one absorptive spectral filter means and at least one luminescence means; (d) as (c), but located inside between two product sheets;
(5) FIG. 4 shows a pattern element with a luminescence pattern element that is located on top in schematic sectional views for illustrating the conditions of light absorption and remission: (a) when viewing with light in the visible spectral range; (b) when viewing under luminescence conditions;
(6) FIG. 5 shows a pattern element with a luminescence pattern element that is located at the bottom in schematic sectional views for illustrating the conditions of light absorption and remission: (a) when viewing with light in the visible spectral range; (b) when viewing under luminescence conditions;
(7) FIG. 6 shows two different pattern elements having in each case one absorptive pattern element that is located on top in schematic sectional views for illustrating the conditions of light absorption and remission: (a) when viewing with light in the visible spectral range; (b) when viewing under luminescence conditions;
(8) FIG. 7 shows an arrangement of an inkjet printer having five print heads and a product carrier with pattern elements in schematic view;
(9) FIG. 8 shows the structure for inkjet printing of the absorptive spectral filter means and of the luminescence means in schematic illustration.
(10) In the figures, identical reference numerals designate elements having the same function.
DESCRIPTION OF THE INVENTION
(11) The valuable and/or security document 100 shown in FIG. 1 is an ID card, which was produced for example by laminating a plurality of product sheets made of polycarbonate. Said ID card has, on the upper side 101 thereof shown here, in fields 102, 103, 104, diverse details relating to the card owner, including a facial image of said card owner. These details represent personalization details. The facial image is a security feature 200 and represents a pattern 201 made of pattern elements which are formed, in a manner according to the invention, of absorptive pattern elements 210 and luminescence pattern elements 220 (in a structure for example as shown in FIG. 6a). The facial image is formed using a printing method, for example an inkjet printing method. So as to be able to reproduce the facial image in color, a plurality of print extracts were produced and printed one on top of the other (not illustrated). By way of example, the various print extracts can be produced successively on the same surface in one printing cycle in an inkjet printing method using the absorptive spectral filter means necessary herefor and the luminescence means which are applied by corresponding print heads of the printer. To this end, the inkjet printer D can have, in addition to the print heads for the colors cyan (C), magenta (M), yellow (Y) and key (K), a further print head (L) with which the luminescence pattern elements are printed. An apparatus that is suitable for this purpose is shown in FIG. 7. One advantage of this procedure is that no adjustment step is necessary and the manufacturing time is thus extraordinarily short. Alternatively, the printer can merely have the four print heads C, M, Y, K, wherein each of the four printing colors is present in the form of an absorptive spectral filter means suitable herefor in a mixture with a luminescence means L, wherein all printing colors contain the same luminescence means. So as to protect the facial image and the remaining details relating to the document owner against forgery and/or falsification and/or copying, the upper side of the card has subsequently also been coated with an overlay layer made of an abrasion-resistant material, for example of PET or a protective varnish (not illustrated).
(12) For the verification of the document 100, said document is illuminated under conventional illumination with a substantially white light source VIS (FIG. 2a). The facial image 200 appears in color under these illumination conditions and naturally reproduces the image of the document owner. In addition, the ID card can also be examined under illumination conditions in which it is illuminated exclusively with UV excitation radiation, i.e. except for the luminescence, the illumination space is completely or at least largely dark. For this purpose, a UV light source UV is used, which emits for example electromagnetic radiation at 365 nm. Since the luminescence means is illuminated by the UV excitation radiation and therefore emits luminescence radiation which is in turn filtered by the absorptive spectral filter means, the facial image appears in color even under these illumination conditions, specifically is luminous (FIG. 2b).
(13) FIG. 3 shows a plurality of options for forming the pattern elements 280 that form the pattern 201 and are formed by the at least one absorptive spectral filter means and the at least one luminescence means. The pattern consists of a plurality of pattern elements which together form the pattern that is perceived by the observer. Instead of a pattern that is rastered in this manner, said pattern can also be configured in non-rastered form. The individual pattern elements can be formed according to FIGS. 3a to 3d in different ways or in a carrier 110, for example printed thereon:
(14) According to FIG. 3a, first absorptive pattern elements 210, which are formed by the at least one absorptive spectral filter means, are formed on the carrier 110 in the form of an absorptive pattern element layer 240. The pattern elements 280 in this and the following examples are illustrated merely by way of example relative to one another. It is of course also possible for the pattern elements to be produced at least partially also such that they join one another directly and/or overlap one another. Conventional printing colors can be formed using the at least one absorptive spectral filter means. It is possible to produce and print in particular a plurality of print extracts with different printing colors which together form the colored pattern, for example the facial image 200 in FIG. 1. Subsequently, luminescence pattern elements 220, which are formed by the at least one luminescence means, are produced on the absorptive pattern elements in the form of a luminescence pattern element layer 250. The luminescence means can contain for example at least one luminescence substance, for example rhodamine 6G or fluorescein or a mixture of said substances. One of the printing colors can additionally have a luminescence, for example in a magenta color. The luminescence pattern elements are formed largely in accurate alignment on the absorptive pattern elements.
(15) The produced pattern 201 shows a colored representation both when illuminated with visible light (VIS) and when excited with UV light (UV).
(16) According to FIG. 3b, initially luminescence pattern elements 220, which are formed by the at least one luminescence means, are produced on the carrier 110 in the form of a luminescence pattern element layer 250. Subsequently, absorptive pattern elements 210 are formed on the luminescence pattern elements in the form of an absorptive pattern element layer 240. The absorptive pattern elements are also formed largely in accurate alignment on the luminescence pattern elements. With respect to the structure of the pattern elements 280 made of absorptive and luminescence pattern elements and the selection of the luminescence means and absorptive spectral filter means, reference is made to the example in FIG. 3a.
(17) The produced pattern 201 exhibits a colored representation both when illuminated with visible light (VIS) and when excited with UV light (UV).
(18) According to FIG. 3c, pattern elements 280 are formed on a carrier 110 in the form of combination pattern elements 230 which form a pattern element layer 260 and which are formed both by the at least one luminescence means and by the at least one absorptive spectral filter means. With respect to the selection of the luminescence and absorptive spectral filter means, reference is made to the example in FIG. 3a. The pattern elements are also produced in this case in a plurality of color extracts. To this end, color material that contains in each case at least one luminescence means and, depending on the color extract, one of a plurality of absorptive spectral filter means is used.
(19) The produced pattern 201 exhibits a colored representation both when illuminated with visible light (VIS) and when excited with UV light (UV).
(20) A single pattern element layer 260 made of pattern elements 280 is produced for example even if absorptive pattern element layers 240 and luminescence pattern element layers 250 which are located on top of each other (such as according to FIG. 3a or 3b) are formed on a product sheet 110, and said product sheet is then combined with a further product sheet 110′ and processed further, under the action of increased temperature and increased pressure, to form a laminate. In this case, the luminescence means and absorptive spectral filter means diffuse into the adjoining product sheets 110, 110′ and also in each case into one another, such that a single pattern element layer 260 made of combined luminescence and absorptive pattern elements is formed (FIG. 3d).
(21) FIG. 4 shows the conditions under irradiation with white light (VIS) (FIG. 4a) and under UV radiation (UV), for example with narrowband radiation at 312 nm, (FIG. 4b). The visible light is symbolized by the basic colors blue (b), green (g) and red (r). These color components pass through the luminescence pattern element 220 that is located on top, without being absorbed by it or scattered by it to any significant extent. To this end, the at least one luminescence means, which forms said luminescence pattern element, is entirely or at least largely radiation-transmissive in the visible spectral range and also preferably non-scattering, and therefore transparent (or, if appropriate, translucent) and colorless (or colored only slightly). The absorptive pattern element 210, which is located in FIG. 4a under the luminescence pattern element, has red and green absorption and therefore appears to be blue to the human eye. For this reason, the red component (r) and the green component (g) of the incident light are absorbed in the absorptive pattern element 210, while the blue component (b) passes through the absorptive pattern element and is remitted. On account of the remission of said light component, the pattern element 280 appears blue.
(22) FIG. 4b shows the conditions under illumination only with UV light (UV). The UV radiation entering the pattern element 280 produces, in the luminescence pattern element 220 that is located on top, nearly white luminescence light with the color components blue (b), green (g) and red (r). Said radiation is emitted without a specific direction and passes into the absorptive pattern element 210 located thereunder, where it is filtered: the red component (r) and the green component (g) are absorbed in the absorptive pattern element, while the blue component (b) passes through and is remitted. As a result, said pattern element appears to be luminous in blue on account of the UV excitation.
(23) The same conditions come about also when a luminescence pattern element 220 is located at the bottom and an absorptive pattern element 210 is located on top, which form in each case a luminescence pattern element layer 250 and an absorptive pattern element layer 240 (FIG. 5). Under illumination with visible light (VIS) (FIG. 5a), in this case the red component (r) and the green component (g) are already absorbed in the absorptive pattern element that is located on top, such that the pattern element 280 appears blue overall. Under illumination with UV radiation (UV) (FIG. 5b), said illumination passes through the absorptive pattern element. To this end it is of course necessary for said absorptive pattern element to be transmissive for UV radiation and if possible not be scattered. Broadband visible luminescence radiation having a blue component (b), a green component (g) and a red component (r) is produced in the luminescence pattern element. Only the blue component of said radiation can pass through the absorptive pattern element that is located on top since the green component and the red component are filtered out by the absorptive pattern element.
(24) FIG. 6 furthermore shows the conditions with two different pattern elements 280, 280′, which differ from one another with respect to the spectral absorption of the absorptive pattern element 210, 210′. The luminescence pattern elements 220 are located at the bottom and the absorptive pattern elements 210, 210′ are located on top. The luminescence pattern elements together form a luminescence pattern element layer 250, and the absorptive pattern elements together form an absorptive pattern element layer 240. The two luminescence pattern elements are formed with the same luminescence means. By contrast, in each case different absorptive spectral filter means are present in the two absorptive pattern elements. The left-hand pattern element 280 that is located on top in each case has an absorptive pattern element 210, which absorbs the red component (r) and the green component (g) of visible radiation (VIS) and appears blue (b), and the in each case right-hand pattern element 280′ has an absorptive pattern element 210′ which absorbs the blue component (b) and the green component (g), such that said pattern element 280′ appears red (r). This structure corresponds to that shown in FIG. 5.
(25) FIG. 6a shows the situation for illuminating and viewing the pattern with visible light (VIS), and FIG. 6 with UV excitation radiation (UV). Of the visible radiation, only the blue component (b) is remitted in the left-hand pattern element 280, while this is the red component (r) in the right-hand pattern element 280′. For this reason, the left-hand pattern element is perceived as blue and the right-hand pattern element as red when illuminated with visible light. With UV radiation, a corresponding image appears as follows: the red component (r) and the green component (g) of the luminescence light are absorbed in the left-hand absorptive pattern element 210 that is located on top, such that only the blue component (b) of the luminescence light is emitted by the left-hand pattern element 280, while in the right-hand absorptive pattern element 210′ that is located on top the blue component (b) and the green component (g) of the luminescence light are absorbed and only the red component (r) of the luminescence light is emitted by the right-hand pattern element 280′. For this reason, the pattern 201 produced by luminescence looks substantially like the pattern obtained under visible light radiation.
(26) In a further exemplary embodiment according to the invention, a luminescence layer with a luminescence means and an absorptive layer with an absorptive spectral filter means are formed by printing them directly one on top of the other onto the same surface of a polymer film. The luminescence means are luminous in approximately white under excitation with UV radiation. The two layers are produced using inkjet print. The absorptive layer is formed on the luminescence layer that is printed first. In FIGS. 8A, 8B, 8C and 8D, different examples are indicated. In each case shown to be located on top (I) are luminescence patterns that are formed with luminescence means, and thereunder (II) absorptive patterns that are formed with absorptive spectral filter means. Shown to be at the very bottom (III) are in each case the patterns that are printed on top of one another to form an overall pattern.
(27) According to the example of FIG. 8A, the first name of the document owner and the date are printed in the luminescence color and the owner's facial image is printed with a conventional printing paint which contains an absorptive spectral filter means. Together, this gives an overlay of the first name of the document owner and the date with the facial image thereof, with the first name and the date becoming visible only if the representation is irradiated with UV radiation. In the regions of the first name and of the date, which are not overlaid by the facial image, they appear in the original luminescence color of the luminescence means, that is to say approximately white. In the regions that are overlaid by the facial image, the first name and the date appear in the color of the facial image even under luminescence illumination conditions.
(28) According to the example of FIG. 8B, a full-area field is printed with the luminescence color and the facial image of the document owner is printed with a conventional printing paint which contains an absorptive spectral filter means. Together this gives an overlay of the field with the facial image of the document owner, with the field being visible only if the representation is irradiated with UV radiation. In the regions of the field that are not overlaid by the facial image, the field appears in the original luminescence color of the luminescence means, that is to say approximately white. In the regions which are overlaid by the facial image, the field appears in the color of the facial image under luminescence illumination conditions.
(29) According to the example of FIG. 8C, the facial image of the document owner is printed in the luminescence color and the facial image thereof is printed in addition with a conventional printing paint that contains an absorptive spectral filter means, one on top of the other in accurate alignment. Together, the facial image of the document owner appears under illumination with visible light in a natural color distribution and under illumination with UV radiation likewise with the natural color distribution.
(30) According to the example of FIG. 8D, a line pattern is printed in the luminescence color and the facial image of the document owner is printed with a conventional printing paint which contains an absorptive spectral filter means. Together this forms an overlay of the line pattern with the facial image of document owner, with the line pattern becoming visible only if the representation is irradiated with UV radiation. In the regions of the line pattern that are not overlaid by the facial image, the line pattern appears in the original luminescence color of the luminescence means, that is to say approximately white. In the regions which are overlaid by the facial image, the line pattern appears under luminescence illumination conditions in the color of the facial image.
(31) The luminescence layer in the examples of FIG. 8 can be configured either in rastered or non-rastered print. Said print can also be produced by a planographic method, such as the offset printing method. In the same way, the absorptive layer in these examples can be configured to be either rastered or non-rastered. Preferably, at least the absorptive pattern is produced by a digital printing method, such as inkjet method, so as to use the flexibility thereof for personalizing patterns.
