EP2143565B1 - Safety paper and method for its production - Google Patents

Abstract

Claimed is a security paper for the production of e.g. banknotes or identity cards, and incorporating two or more holes (12, 16). The first hole (12) is formed during the paper manufacturing process and bears characteristic marginal (14) irregularities. The second hole is incorporated after the paper manufacturing process has been completed. The second hole is formed by cutting or punching and has a sharply defined edge (18). The two holes have a spatial relationship to each other. The margins around each hole bear supplementary information relating to each other e.g. an image, mark or code. The second hole is surrounded by foil and cut by laser beam. The security paper product is of pre-determined thickness and further incorporates a zone of reduced thickness incorporating the second aperture and a watermark. Further claimed is a process to manufacture a commensurate security document.

Description

The invention relates to a security paper for the production of security or value documents, such as banknotes, ID cards and the like.

Security documents or documents of value are often provided with various authenticity features for the purposes of security, which permit verification of the authenticity of the security paper or value document and at the same time serve as protection against unauthorized reproduction.

For the purposes of the invention, the term "security paper" here refers to the unprinted paper, which is usually in quasi-endless form and is further processed at a later time. A "document of value" is a document that has been completed for its intended use. Value documents within the meaning of the present invention are, in particular, bank notes, shares, bonds, certificates, vouchers, checks, high-quality admission tickets, but also other papers which are subject to counterfeiting, such as passports and other identification documents, as well as product security elements such as labels, seals, packaging and the like. The simplified term "security paper" or "value document" below includes all such documents and product security means.

The publication WO 95/10420 describes a document of value, in which after its production a continuous opening is punched, which is then closed on one side with a cover projecting the opening on all sides. The cover film is transparent at least in a partial area, so that when attempting to copy the document of value, the substrate shines through and reproduced by the copying machine accordingly. On This way counterfeits can be easily recognized. However, the hole created by punching can be generated by a counterfeiter as well. Although the color copy of a true value document no longer has the transparent area, this area can subsequently be punched out analogously to the real value document and closed again with a suitable cover film. Such counterfeits are difficult to recognize.

The remedy is in the document WO 03/054297 has been proposed already to produce a through opening during papermaking. Such an opening, which is produced during sheet formation, has characteristic irregularities in the edge region which subsequently can not be produced on the finished paper. The irregularities are manifested in particular by the absence of a sharp cutting edge or by irregular attachment of fibers in the edge region and by protruding into the opening of individual fibers. Openings produced in this way have a similarly high security value as a watermark produced during papermaking or a security thread embedded in papermaking.

However, such apertures produced in papermaking often vary in quality and are not easily reproducible to make. Partly there is also the danger that fiber bundles close the opening to part.

GB-A-2 390 056 discloses a security paper with an embedded film element, which is visible in partial areas by papermaking window areas.

GB-A-1604 463 discloses a security paper having an embedded film element which has an opening created by cutting or punching in the region of the film element.

Proceeding from this, the object of the invention is to provide a security paper which avoids the disadvantages of the prior art. In particular, the security paper is intended to ensure high counterfeit security of the openings produced in papermaking with high reproducibility connect in the manufacture and good recognizability of the authenticity features formed by the openings.

This object is solved by the features of the independent claims. Further developments of the invention are the subject of the dependent claims.

In a first aspect of the invention, a generic security paper includes at least two through openings wherein a first one of the through openings is formed during papermaking and has characteristic irregularities in the periphery, and a second of the through openings is made after papermaking by cutting or punching with a sharply defined edge area is.

The outline shapes of the first and second through openings are preferably in a sense context. In particular, it may be provided that the outline shapes of the first and the second through opening represent information that is related or complementary to one another, such as a picture motif, characters or an encoding.

In a preferred embodiment, the second, sharply defined opening is produced by laser cutting. The sharply delimited edge surfaces of the second opening can run parallel and perpendicular to the paper surface. In other embodiments, however, the second opening is formed with edge surfaces inclined towards the surface normal. This can be achieved, for example, in laser cutting by a suitable choice of the beam divergence and the beam inclination relative to the paper surface. In particular, beam divergence and beam tilt to the paper surface can be adjusted so that the second aperture is against the surface normal different inclined edge surfaces is generated. Flattened edges result in a smoother transition between a covering foil arranged over the openings and the paper substrate, and thus, inter alia, a lower susceptibility to soiling.

In addition, differently inclined edge surfaces offer advantages in laminating the opening on both sides with foils, and in particular minimize the problem of air entrapment in the case of mutual lamination. Furthermore, the openings with inclined edge surfaces with respect to vertical edge surfaces on an additional visual effect, since they appear different sizes depending on the viewing direction.

In an advantageous development of the invention, the security paper has a predetermined paper thickness and a thin point with reduced paper thickness, wherein at least the second through opening is introduced in the region of the thin point. The thin spot may in particular comprise a watermark.

The two openings are expediently closed on at least one side of the security paper with a film element. In some designs, the openings are even closed on both sides with a foil. In this case, possible problems of air entrapment can be minimized by the above-mentioned inclined edges.

According to a further aspect of the invention, a generic security paper contains at least one through opening, wherein the edge surface of the through opening has first, sharply delimited partial areas and second partial areas with characteristic irregularities. First and second portions preferably alternate with each other along the contour of the opening. In particular, it can be provided that first and second portions alternate with each other along the contour of the opening in an irregular sequence.

In one embodiment, first and second partial regions each extend through the entire paper thickness. It can also be provided that first and second subareas follow one another in a direction along the thickness of the security paper and supplement one another to the through opening. For example, in one edge portion, sharply defined portions may extend through 90% of the paper thickness while the edge surface is irregular for the remaining 10% of the paper thickness. Such edge portions may also be combined with other edge portions in which first or second portions extend completely through the entire paper thickness.

Such a sequence of first and second partial areas along the thickness of the security paper can be produced, for example, by producing a continuous opening with characteristic edge irregularities during papermaking, and modifying the edge area of the opening thus created after papermaking by cutting or punching and characterized sharply limited, at least in some areas. The modification is preferably produced by laser cutting, wherein here too the above-mentioned possibilities of inclination of the edge surfaces exist.

The sequence of first and second portions along the thickness of the security paper may also be created, for example, by defining a piece of paper having the desired shape of the opening with broken, sharply defined cut lines in the security paper, and then tearing the piece of paper thus defined out of the security paper . in particular blown out or pulled out. The piece of paper is preferably defined by laser cutting, in turn, there are the above-mentioned possibilities of inclination of the edge surfaces.

A further possibility of generating the sequence of first and second partial areas is that a sharply delimited thin spot having the shape of the desired opening is produced in the security paper, and that the piece of paper formed in the region of the thin spot by the residual paper thickness is torn out of the security paper, in particular blown out or pulled out. Also, the sharply defined thin spot is produced in a preferred process control by laser cutting, if desired, with inclined edge surfaces, as explained above.

In an expedient embodiment, the security paper has a predetermined paper thickness and a thin area with reduced paper thickness, for example a watermark, wherein the through opening is introduced in the region of the thin point.

The through opening is suitably closed on one or even on both sides of the security paper with a film element.

In a further aspect of the invention, a generic security paper contains at least one through opening produced during papermaking, which has characteristic irregularities in the edge region. The through-hole is combined with an engraving created by laser etching, which complements the aperture to a projection image. Preferably, the through opening is closed on one or even on both sides of the security paper with a film element.

According to yet a further aspect of the invention, a generic security paper contains an embedded film element, which is visible in partial areas by papermaking-made window areas. The security paper further has, in the region of the film element, an opening produced by papermaking by cutting or punching with a sharply delimited edge area.

In an advantageous embodiment, the sharply defined opening is arranged above and / or directly next to the film element. Preferably, the sharply defined opening is formed with the exception of a possible overlap region with the film element continuously.

The window areas are arranged according to a preferred embodiment on a first main surface of the security paper, while the sharply defined opening extends from the opposite major surface of the security paper to the film element.

In all embodiments, the film element may be a security element, in particular a security thread or a security band.

The sharply defined opening is advantageously produced by laser cutting. In this case, the edge surfaces of the opening may be inclined, as explained above. In an expedient embodiment, the security paper has a predetermined paper thickness and a thin location with reduced paper thickness, for example a watermark, wherein the sharply defined opening is introduced in the region of the thin location. The well-defined opening is suitably closed on one or even on both sides of the security paper with a film element.

The invention also includes a value document, such as a banknote, an identity card and the like, with a security paper of the type described. The security paper or document of value according to the invention can be used for the counterfeiting of goods of any kind.

Further exemplary embodiments and advantages of the invention are explained below with reference to the figures, in the representation of which a representation true to scale and proportion has been dispensed with in order to increase the clarity.

Show it:

Fig.1

a schematic representation of a banknote from a security paper according to an embodiment of the invention,

Fig. 2

a plan view of a security paper according to another embodiment of the invention,

3 and 4

Further embodiments of embodiments according to the invention of two, in a meaningful openings in a security paper,

Fig. 5 to 7

in each case in (a) an intermediate step in the production of the security paper shown in plan (b) according to further exemplary embodiments of the invention,

Fig. 8

in (a) an intermediate step in the production of a security paper according to a further embodiment of the Invention, and in (b) a section of (a) after the extraction of the cut-out shape,

Fig. 9

a plan view of a security paper according to another embodiment of the invention,

Fig. 10

in (a) a plan view of a security paper with an embedded film element according to an embodiment of the invention, and in (b) and (c) cross sections through the security paper of (a) along the lines B-B and C-C respectively,

FIGS. 11 and 12

each in (a) a top view of a security paper with film element according to further embodiments of the invention, and in (b) and (c) cross-sections through the security paper of (a) along the lines B-B and C-C respectively,

Fig. 13

a design in which a laser-cut opening is produced in the region of a paper-made thin spot,

Fig. 14

in (a) and (b) in cross-section two steps in the production of a security paper according to a further embodiment of the invention, and in (c) a top view of the security paper of (b),

Fig. 15

in (a) to (c) a representation as in Fig. 14 , wherein the laser-cut opening is produced in the region of a papermachined thin spot, and

Fig. 16

in (a) and (b) two embodiments of laser-cut openings with against the surface normal inclined edge surfaces.

The invention will now be explained in more detail using the example of a banknote. Fig.1 shows a schematic representation of a banknote 10, which has two through openings 12 and 16, respectively. The first of the through openings 12 was produced during the production of the security paper used for the banknote 10 and has a fibrous, irregular edge region 14. Such an edge 14 is characteristic of the openings already made in the sheet formation and can not be subsequently produced by punching or cutting the paper.

The second through opening 16 was produced only after the papermaking by laser cutting or by means of a punching tool and has a sharply delimited edge region 18. The two through openings 12 and 16 show, spatially separated, twice the same information, in the embodiment of Fig.1 one isosceles triangle each. It is understood that instead of the triangle also more complex shapes can be used, the outlines of which represent, for example, a number sequence or a simple graphic.

Even if the information represented by the first opening 12 should not immediately be recognizable by its irregular edge region 14, the observer can establish the relationship of the two forms through the second opening 16 formed with clear contours and recognize the information without any doubt. By presenting the information twice in different guises, the viewer's attention and attention are directed to the difference between the two openings. The high counterfeiting security of the irregularly bounded opening 12 is thus combined with the clear recognizability of the sharply edged opening 16.

The section of the Fig. 2 shows a plan view of a security paper 20 according to a further embodiment of the invention. The security paper 20 has a first paper-made opening 22 with an irregular edge area 24 and a second opening 26 produced by laser cutting with a sharp edge 28. Again, the outline of the two openings 22 and 26 with each other in a context of meaning. In contrast to the embodiment of Fig.1 However, they do not present the same information, but form complementary parts of an overall information.

Preferably, the illustrated motif is adapted to the different edge properties of the two openings. For illustration shows Fig. 2 a flower motif in which the flower through the first, irregularly bounded opening 22 and the stem and the leaves through the second, sharply edged opening 26 are formed. Since flowers look very different and variable in nature, the overall picture looks very realistic. At the same time a high protection against counterfeiting is ensured by the use of the two opening forms.

Figures 3 and 4 show further embodiments of designs in which the outline shapes of an irregularly bounded first opening and a sharply edged second opening in a meaningful context.

The embodiment of Fig. 3 (a) shows a sun in the form of a circular, irregularly edged first opening 32 with radially outward pointing rays, which are formed by laser-cut or punched triangular openings 34. The beams formed by the second openings 34 represent in this embodiment, a dependent of the first opening motif. Also in Fig. 3 (b) For example, the irregularly bounded, star-shaped, first opening 36 is a major motif from which the sharply edged, circular, second openings 38 depend graphically.

Fig. 4 shows a further embodiment of the invention, in which the irregularly bounded openings 42 and the sharply edged openings 44 in each case complement the denomination "100" of a banknote 40. As usual, the denomination of the banknote is applied again clearly readable elsewhere, for example, printed. In a real banknote, only one of the designs of the Fig. 4 can be used or it can be provided both at different locations of the bill and possibly other designs.

A sense context of the two types of opening can also result from the fact that the irregularly bounded opening is modified by the sharply edged opening, as now with reference to the FIGS. 5 to 7 explained. Fig. 5 (a) shows a plan view of a security paper 50, in the paper making initially a first, irregularly bounded opening 52 has been introduced. The opening 52 is modified after papermaking by laser cutting with two sharply edged openings 54 whose positions in Fig. 5 (a) dashed lines are shown.

After laser cutting results in a single continuous and continuous opening 56, which, as in Fig. 5 (b) shown due to the two-stage production on the one hand part areas 58 with irregular edge and on the other hand, portions 59 with sharp edge. By a such modification, the edge properties of the two types of openings can be combined in a single through opening.

In the embodiment of the Fig. 6 During papermaking, in a first step, an irregularly bounded opening 62 in the form of a predetermined figure, for example in the form of in FIG Fig. 6 (a) shown four-headed figure, generated in a security paper 60. The irregular edge region 64 of this figure is then partially recut with a laser. As in Fig. 6 (b) illustrates, there is thus a through opening 66, which on the one hand has partial regions 68 with an irregular edge and, on the other hand, partial regions 69 with a sharp edge. The ratio and the sequence of subregions 68, 69 can be chosen arbitrarily.

Fig. 7 shows a further embodiment in which, as in the embodiment of Fig. 6 Initially, an irregularly bounded opening 72 is inserted into a security paper 70, as in Fig. 7 (a) shown. After papermaking, the aperture 72 is completely re-cut with a laser (reference numeral 74), the size of the re-cut 74 being selected to be slightly smaller than the size of the aperture 72. In this way, a through opening 76 is formed, which has portions 78 with an irregular edge and portions 79 with a sharp edge in an irregular sequence, as in FIG Fig. 7 (b) shown.

A sequence of regular and irregular marginal areas can also be achieved without the involvement of an opening already created in papermaking. For example, the desired shape of a through opening 82 can be cut out of a security paper 80 by means of a laser in such a way that the cut lines 84 do not form a continuous cut curve, but rather through uncut cuts 86 are interrupted, as in Fig. 8 (a) shown. The sections 86 form holding webs, which initially prevent the release of the cut-out shape.

The cut-out shape can then be blown out, for example, with an air jet or pulled out by means of vacuum. As in the in Fig. 8 (b) illustrated in detail section 85, tears the cut piece of paper in this procedure on the support webs 86 in an irregular manner, while the cutting lines 84 form sharp edges. The edge region to the opening 82 thus has a sequence of irregular subregions 88 and sharply cut subareas 89, the relative size and sequence of which can be selected almost arbitrarily by the cutting guide during laser cutting.

In the further, in Fig. 9 In the embodiment of the invention shown, the security paper 90 has a continuous opening 92 with an irregular, fibrous edge, which is produced during papermaking. The opening 92 is combined with engraving lines 94 created by laser etching. The engraving lines 94 are formed by locally thinned areas in the security paper 90, such as in the document WO 98/03348 described, whose disclosure content is included in this description in this respect. Location and arrangement of the engraving lines 94 are inventively chosen so that they complement the opening 92 to a projection view.

When viewed in incident light, the engraving lines 94 are virtually invisible, where the flat shape of the opening 92 determines the appearance. If, on the other hand, the security paper is viewed in transmitted light, the engraving lines 94 clearly emerge due to the smaller paper thickness and supplement the two-dimensional opening 92 into a three-dimensional projection representation. The combination of the irregular opening 92 with the engraving lines 94 thus leads to an optically conspicuous interplay between 2D and 3D representation.

According to a further embodiment of the invention, which now with reference to the FIGS. 10 to 12 is described, the security paper with a film element, such as an embedded security thread or a one-sided covered film strip provided.

Figure 10 shows by way of example a security paper 100 in which a film strip 102 is embedded. It puts Figure 10 (a) a supervision of the security paper that FIGS. 10 (b) and 10 (c) show cross sections through the security paper of Fig. 10 (a) along the lines BB and CC. Before being embedded in the security paper on the underside 104, the film strip 102 was coated over its entire surface with hot-sealing lacquer 107. On the other hand 106, on the other hand, only traces 108 on the edge of the film have been provided with heat-sealing lacquer, so that the middle film region of the upper side 106 remains uncoated.

During papermaking, a nonwoven fabric now forms on both sides of the film. In addition, a window 110, for example by means of electrotypes, is recessed on the lower side 104 of the foil strip in which the foil element becomes visible. On the underside 104, which is coated all over with heat sealing lacquer 107, the fiber fleece is fixed except for the recessed window 110 in the drying section. On the opposite front side 106, on the other hand, only the heat-sealing lacquer-covered edge regions 108 are fixed in the drying section.

Subsequently, a mold 112 is cut out with a laser over the recessed window 110 of the opposite side 104, as best seen in the cross-sectional view of FIG Fig. 10 (c) to recognize. The laser parameters are chosen so that only the paper, but not the film strip 110 is cut. This can be achieved, for example, by performing the laser cutting with a laser wavelength for which the film strip 102 is transparent and non-absorbent.

The cut-out mold 112 can then be removed with a suction device, since no connection of the cut piece of paper with the film has been achieved due to the lack of heat-sealing lacquer coating on the front side 106 and the non-stick film surface.

Another embodiment with foil element will now be described with reference to Figures 11 and 12 explained. First, poses 11 (a) a view of a security paper 120 and the FIGS. 11 (b) and 11 (c) show cross sections through the security paper of 11 (a) along the lines BB and CC. Embedded in the security paper 120 is a security thread 122, which is primarily visible in the paper-made generated areas 124 of the paper back, as in FIG Figure 11 (b) shown.

Further, in the region of the window 124, from the front side of the security paper 120, a sharp-edged opening 126 is inserted into the paper substrate with a laser and extends over the security thread 122. For this purpose, the laser parameters are selected so that, although the paper substrate 120, but not the security thread 122 is cut by the laser. In the region of the opening 126, the security thread 122 is then recognizable from both sides, as in FIG Figure 11 (c) shown.

At the in Figure 12 As shown alternative design is the laser cut opening 128 in contrast to the embodiment of Figure 11 not passed over the security thread 122, the security thread is rather framed by the opening 128. Except for this difference, the views of the FIGS. 12 (a) to (c) those of FIGS. 11 (a) to (c) ,

Unlike Figure 11 is in the embodiment of Fig. 12 the surface of the security thread 122 can be seen only in the window areas 124. Such a configuration is particularly suitable when the laser radiation could damage or undesirably affect the film material of the security thread 122. Typically, because the security thread is oscillating, the opening 128 in this configuration can not be perfectly centered on the security thread 122, as shown in FIGS FIGS. 12 (a) and (c) indicated Passerschwankungen indicated.

Figure 13 shows a design in which a sharp-edged opening 132 is produced in the region of a thin spot 134 of the security paper 130 with a laser. The thin spot 134 can be produced, for example, by a suctioned short-forming layer (a paper layer produced by spraying the pulp onto a round screen) or by means of electrotypes. Since the paper thickness is reduced in the region of the thin spot 134, can be used in laser cutting with lower laser power. As a result, higher cutting speeds are achieved, so that more complex shapes can be realized. This modification can be combined with all embodiments in which a laser is used to inscribe a sharply edged opening in a paper substrate.

Further embodiments of the invention will now be described with reference to FIG Figures 14 and 15 explained. In the embodiment of the Fig. 14 At first, a thin spot 142 of predetermined shape is produced in the paper substrate 140 by means of a laser. The paper material is vaporized, burned or otherwise removed. It is just removed so much material that still a small residual thickness 144 of the substrate remains, as in Fig. 14 (a) shown. Depending on the thickness tolerance of the substrate can be removed in some places so much that no material is no longer available. Since the thin spot is produced by laser cutting, the peripheral surface 146 is sharply defined and smooth.

The piece of paper 144 remaining after the laser treatment is then removed by blowing out or sucking it out. Since it is only a very thin paper layer, the piece of paper 144 tears at the edges and thereby creates an irregular portion 148 in the edge surface of the now continuous opening 145, as in the cross-sectional view of Figure 14 (b) and the supervision of Fig. 14 (c) shown.

Following the edge surface of the aperture 145 along a direction extending through the paper thickness beginning at the surface 141 of the paper substrate, the sharply defined portion 146 and the characteristically irregular shaped portion 148 follow each other.
When viewing the security paper, the through opening 145 appears from opposite sides of the security paper with varying degrees of impression, depending on whether the sharp bounded edge area 146 or the irregular edge area 148 is adjacent to the paper surface.

As an exemplary combination of laser-generated openings with thin spots in the paper substrate ( Fig. 13 ) shows the embodiment of Figure 15 first, a thin paper 151 produced in the security paper 150, such as a watermark. In the area of this thin spot 151 is then, as in Related to Fig. 14 described with the laser generates a second sharply edged thin spot 152, which leaves only a small residual thickness 154 of the paper substrate, as in Fig. 15 (a) shown.

This remaining paper piece 154 is torn out by blowing or sucking, so that an irregular edge surface 158 is formed on the underside of the paper substrate 150, as in FIG Figure 15 (b) shown. By contrast, the edge region 156 produced by laser cutting is sharply delimited. The resulting through opening 160 is embedded in a watermark area 151, which clearly appears when viewed in phantom, see Figure 15 (c) , It is understood that the shape of the opening 160 and the watermark area 151 may also be correlated with each other.

Overall, the edge surface of the opening 160 has, along a direction extending through the paper thickness, successively a sharply delimited subregion 156 and a characteristically irregularly shaped subregion 158. Again, when viewed from opposite sides of the security paper, the through opening 160 will appear to have a different impression depending on whether the sharp bounded edge area 156 or the irregular edge area 158 is adjacent the paper surface.

In the described embodiments, the sharp-edged opening can be generated by a punching tool instead of a laser. Also, it is not necessary for the edge surfaces of the laser-cut apertures to be parallel and perpendicular to the paper surface, as shown in the figures for ease of illustration. Rather, it can be beneficial to skew the laser source and / or the paper as it cuts so that "flattened" edges are created.

Fig. 16 shows in (a) and (b) two embodiments in which sharp-edged, laser-cut openings 172 and 174 are introduced into paper substrates 170. The slope of the marginal surfaces 178 of the apertures can be adjusted as desired by choosing an appropriate beam divergence and beam tilt. The openings 172 and 174 are each covered with a film 176. As can be seen immediately, the flattened edges result in a smoother transition between the film 176 and the paper substrate 170. Such edge shapes significantly reduce the susceptibility of the openings to fouling.

The design of the Figure 16 (b) in which the edge surfaces have different inclinations, moreover, in a (not shown) mutual lamination of the openings with films has proven to be particularly advantageous. Problems with the possible inclusion of air between the opposing films can be minimized by such an edge design.

Also have the openings of the Fig. 16 as an additional advantage an additional optical effect, since they appear different sizes depending on the viewing direction.

Claims (23)

1. A security paper for manufacturing security or value documents, such as banknotes, identification cards and the like, having an embedded foil element that is visible in subregions through window regions manufactured with papermaking technology, characterized in that the security paper exhibits, in the region of the foil element, an opening that is produced after paper manufacture, by cutting or punching, having a sharply delimited edge region, and that is disposed over and/or immediately next to the window regions manufactured with papermaking technology.
2. The security paper according to claim 1, characterized in that the sharply delimited opening is continuous, with the exception of a potential overlap region with the foil element.
3. The security paper according to claim 1 or 2, characterized in that the window regions are disposed on a first main surface of the security paper and the sharply delimited opening extends from the opposing main surface of the security paper to the foil element.
4. The security paper according to at least one of claims 1 to 3, characterized in that the foil element constitutes a security element, especially a security thread or a security band.
5. The security paper according to at least one of claims 1 to 4, characterized in that the sharply delimited opening is produced by laser cutting.
6. The security paper according to at least one of claims 1 to 5, characterized in that the security paper exhibits a predefined paper thickness and a thin site having reduced paper thickness, the sharply delimited opening being introduced in the region of the thin site.
7. The security paper according to claim 6, characterized in that the thin site comprises a watermark.
8. The security paper according to at least one of claims 1 to 7, characterized in that the sharply delimited opening is formed having edge surfaces that are tilted against the surface normal.
9. The security paper according to claim 8, characterized in that the sharply delimited opening exhibits edge surfaces of varying tilt against the surface normal.
10. The security paper according to at least one of claims 1 to 9, characterized in that the sharply delimited opening is closed on one or on both sides of the security paper with a foil element.
11. A method for manufacturing a security paper having an embedded foil element, especially according to one of claims 1 to 10, in which

    - during paper manufacture, a foil element is embedded in the security paper,

    - window regions are produced in which the foil element becomes visible, and

    - after paper manufacture, an opening having a sharply delimited edge region is produced in the region of the foil element over and/or immediately next to the window regions by cutting or punching.
12. The method according to claim 11, characterized in that the sharply delimited opening is produced by laser cutting.
13. The method according to claim 11 or 12, characterized in that a through, sharply delimited opening is produced immediately next to the foil element.
14. The method according to claim 12, characterized in that the sharply delimited opening overlaps the foil element, the laser parameters being set such that the laser cuts only the paper substrate, but not the foil element.
15. The method according to at least one of claims 11 to 14, characterized in that, on a first main surface, prior to embedment, the foil element is coated contiguously with heat seal coating, and on a second, opposing main surface, is prepared with heat seal coating only at the foil edge, so that the middle region of the foil element remains uncoated.
16. The method according to claim 15, characterized in that the window regions are produced on the contiguously coated main surface.
17. The method according to claim 15 or 16, characterized in that the sharply delimited opening is produced in the middle region of the main surface that is coated only at the edge.
18. The method according to at least one of claims 15 to 17, characterized in that the sharply delimited opening is produced by laser cutting.
19. The method according to claim 18, characterized in that the beam divergence and beam tilt to the paper surface are set such that the sharply delimited opening is produced having edge surfaces that are tilted against the surface normal.
20. The method according to claim 18 or 19, characterized in that the beam divergence and beam tilt to the paper surface are set such that the sharply delimited opening is produced having edge surfaces that are tilted differently against the surface normal.
21. The method according to at least one of claims 11 to 20, characterized in that the sharply delimited opening is closed on one or on both sides of the security paper with a foil element.
22. A use of a security paper according to at least one of claims 1 to 10 or of a security paper manufacturable according to at least on of claims 11 to 21 for securing goods of any kind against counterfeiting.
23. A value document, such as a banknote, identification card and the like, having a security paper according to at least one of claims 1 to 10 or a security paper manufacturable according to at least on of claims 11 to 21.

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