ES2508440T3 - Watermark security paper - Google Patents

Abstract

Security paper for the manufacture of security and value documents with a watermark that forms a first motif, characterized in that the watermark is superimposed by a recess area that forms a second motif and is formed by at least one recess in the form of lines, generated by the action of a laser radiation on the security paper, so that the superposition of the watermark and the recess area forms a reason for combining the first and second motif, which presents an impression visual modified to the light with respect to reflected light.

Description

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DESCRIPTION

Watermark security paper

The invention relates to a security paper with a watermark, as well as a process for the manufacture of a similar security paper.

Data carriers, such as security, value or identity documents, but also other valuables are often provided for the assurance of security features, which allow a verification of the authenticity of the data carrier and that serve at the same time as protection against illicit reproduction.

First of all, security papers for banknotes, identity documents and the like are often provided for the securing of watermarks, differentiating between two-level watermarks with an intense light-dark effect and multi-level watermarks with smooth transitions between light and dark. For the generation of two-level watermarks, they are welded or welded, for example, metal wires or metal shaped parts, so called electrotypes, on the paper sieve structure, in order to completely close the paper sieve in these points. In this way it is difficult to fix the paper in these partial areas of the paper sieve and thin spots on the paper are formed that seem very clear when observed in the light. For the manufacture of multi-level watermarks, a three-dimensional relief is engraved on the drain screen, so that the thickness of the paper of the finished paper varies according to the relief and the backlight allows to distinguish gradual smooth transitions between lighter and darker areas.

Conventional watermarks show, for example, portraits of people, animals or buildings. Similar watermarks only allow, however, a simple assurance of a security paper provided with them.

EP 1 607 235 A discloses a security paper with the features of the preamble of claim 1.

Based on this, the invention aims to create a security paper with watermarks, which brings together high security against counterfeiting with a high visual appeal.

This objective is achieved by the security paper with the characteristics of the independent claim. A process for the manufacture of such a security paper is specified in the coordinated claim. Improvements of the invention are the subject of the dependent claims.

According to the invention a security paper of the type mentioned at the beginning contains a watermark that forms a first motif, and the watermark is superimposed by a recess area forming a second motif. The recess zone is formed by at least one line-shaped recess, generated by the action of a laser radiation on the security paper, so that the overlapping of the watermark and the recess area forms a combination motif of the first and second motif, which presents a modified visual impression in light of reflected light.

A similar combination motif combines the advantageous properties of the watermarks tested with their modern safety features generated by laser cutting. Through laser radiation, a continuous cutting line or a non-continuous thinning line on the paper is generated on the paper according to the thickness of the local paper. When observing in reflected light, the watermark and the slimming lines cannot be distinguished practically from the area without filigree of the security paper. When observing the light on the contrary, the watermark and the slimming lines are clearly visible. The relative clarity of the watermark areas and the slimming lines can be adjusted in this case over a wide range by the depth of cut and the thickness of the paper in the watermark.

Due to the dependence of the result of cutting the thickness of the local paper a complex interaction of the watermark and laser cutting pattern occurs, so that for the combination reason a multiplicity of visual aspects possible in reflected light is available or to the light. This gives, on the one hand, the designer a great margin of design and, on the other hand, revalued the two individual security features. For the user a visually pleasing combination feature is produced and to be easily examined for authenticity.

The term "notch" is used within the framework of this description as a generic term for continuous openings or cuts and for non-continuous thinning of the security paper. A cut-out in the form of lines or a cut-out line may therefore be a cut line that passes completely through the paper or a non-continuous thinning line with a determined residual residual thickness of the paper.

The aforementioned overlap of the recess zone and the watermark also includes the case that the recess zone and the watermark overlap each other only in a partial area, so that the motive surface

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Total is clearly increased by the combination of the two characteristics.

According to an advantageous variant of the invention, the watermark comprises a thin point with a reduced paper thickness relative to the environment. Alternatively or additionally it may also be provided that the watermark comprises a thick point with an increased paper thickness relative to the environment. The watermark can be configured on two levels or also on several levels. In this case, brands with a very large number of levels and therefore a virtually continuous variation in thickness are also referred to as multi-level watermarks in the context of the description.

The first motive of the watermark advantageously represents a portrait, an architectural, technical or natural motive,

or a succession of alphanumeric characters, in particular a value figure. Character sequences and in particular the value figures, which indicate for example the denomination of a banknote, are conveniently generated with electrotypes such as two-level watermarks.

In an advantageous configuration the first and second motives represent information referred to each other or complementary to each other. For example, the watermark motive information (first motive) can repeat the motif information of the recess zone (second motive) or complement it by forming a global information.

In the synchronization of the first and second motif, it is conveniently taken into account that a watermark within a use has a proportionally large position tolerance. The second motif is therefore preferably designed so that a position tolerance of the first motif of a few millimeters does not impair or destroy the desired combination effect.

The recess area may be formed by a single line-shaped recess in the security paper, for example, by a simple stroke or graphic motif. However, the recess area preferably comprises several recesses in the form of lines and is formed in particular by a multiplicity of recesses in the form of lines in the security paper. Next, for simplicity, we always talk about recesses in the form of plural lines, it being understood that this formulation must always also include the case of only a recess in the form of a line.

Line-shaped recesses can comprise both continuous cutting lines, as well as non-continuous thinning lines through the security paper. If both cutting lines and thinning lines are present in a recess area, then they may be present next to each other in separate areas, or the cutting or thinning lines can also be connected to each other and become one another . Due to the manufacturing by laser cutting in a working stage, the cutting lines and slimming lines are connected to each other in this case without bending.

In an advantageous configuration it is provided that the recess area is completely disposed inside the watermark.

The recess zone can be configured differently. For example, the recess zone may be formed by a multiplicity of straight, parallel, line-shaped recesses, or by a multiplicity of divergent, rectilinear, line-shaped recesses. The recess lines can also be curved, so that the recess area is formed by a multiplicity of curved, equidistant recesses or by a multiplicity of curved, divergent recesses, in the form of lines.

Line-shaped recesses preferably have a width between 0.05 mm and 1 mm, in particular between 0.1 mm and 0.4 mm.

According to an improvement of the invention, the security paper is provided at least in a partial area with a laser modifiable marking substance and the line-shaped recesses present in this partial zone a marginal zone modified by the action of a laser radiation . The security paper is preferably provided in the partial zone with a marking substance, the visible color of which can be modified by the action of the laser radiation, so that the line-shaped recesses have a colored marginal zone in this partial zone.

In the configurations provided with a laser modifiable marking substance, the line-shaped recesses can also comprise both continuous cutting lines and also non-continuous thinning lines through the security paper. If there are both cutting lines, as well as thinning lines, then the cutting lines can be converted in particular into modified thinning lines at the edge, for example colored.

As labeling substances, laser-modifiable effect pigments or laser-modifying labeling substances can be advantageously used. Examples of appropriate marking substances, and the manner and manner of their application or introduction into the security paper can be extracted from WO 2010/072329 A1, the disclosure of which is incorporated in this regard in the present application.

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The security paper may in particular be a single layer or multilayer paper, preferably with a high fraction of cotton. Coated composite papers or materials, in which at least one layer is based on paper, can also be used advantageously according to the invention.

In multilayered associations, as they originate for example in a subsequent meeting of several layers of different substrates, of which at least two layers are based on paper, an area of cut-off generated by laser radiation with a mark can be combined individually. of water. The combination can also be carried out, however, in different layers. For example, a first layer based on the role of a compound may comprise a watermark with a recess zone generated by laser radiation, a watermark in connection with a recess zone generated by laser radiation in a second layer based on the paper, or a recess zone generated by laser radiation in connection with a watermark in a second layer based on the paper. A second paper-based layer may then comprise a watermark with a recess zone generated by laser radiation, a watermark in connection with a recess zone generated by laser radiation in the first layer based on the paper, or a recess zone generated by laser radiation in connection with a watermark on the first layer based on the paper. If the first layer already contains a combination feature, obviously the second paper-based layer may also be feature free.

The invention also comprises a process for the manufacture of a security paper of the mentioned type. In this case a security paper is provided with a watermark that forms a first motif and the watermark is superimposed by a recess area, which forms a second motif and which is formed by a multiplicity of recesses in the form of lines. , generated by the action of a laser radiation on the security paper, so that the overlapping of the watermark and the recess area forms a combination motif of the first and second motif, which presents a visual impression modified with respect to the light in reflected light.

Line-shaped recesses are advantageously generated by laser application with an infrared laser, preferably with a CO2 laser.

In an advantageous improvement, the security paper is provided at least in a partial area of a laser modifiable marking substance, so that the line-shaped recesses are modified in this partial zone by the action of the laser radiation in their marginal zone The security paper is preferably provided in the partial zone of a marking substance, whose visible color can be modified by the action of the laser radiation, so that the line-shaped recesses comprise in this partial zone a marginal zone colored by The action of laser radiation.

Other exemplary embodiments, as well as advantages of the invention, are explained below by means of the figures, in whose representation a reproduction at scale and proportional has been dispensed with to increase clarity.

They show:

Fig. 1

a schematic representation of a banknote with a combination motif according to the invention,

Fig 2

for a combination reason in (a) and (b) the two safety features to be combined, watermark and recess area respectively individually, in (c) a cross section of the security paper in the area of the combination reason, in (d) the aspect of the combination motif generated when observing the reflected light and in (e) the aspect of the combination motif when observing in the light,

Fig. 3

in (a) to (e) a representation as in fig. 2 for a combination reason according to another embodiment of the invention,

Fig. 4

for another combination reason according to the invention in (a) and (b) the two safety features to be combined, watermark and recess area individually, in (c) the aspect of the combination reason generated when observing reflected light and in (e) the aspect of the combination motif when looking at the light,

Fig. 5

in (a) to (e) a representation as in fig. 2 for a combination reason according to another embodiment according to the invention,

Fig. 6

schematically the spatial distribution of energy of a laser cutting beam and the resulting cutting widths in the case of different paper thicknesses,

Fig. 7

the particularity VII of fig. 5 (d) in detail, the laser cutting being performed with a laser beam with the Gaussian bell-shaped energy distribution shown in fig. 6, and

Fig. 8

in (a) to (d) different variants for the configuration of the recess area.

The invention is now explained in the example of a banknote. Fig. 1 shows a representation 10

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schematic of a banknote 10 with a combination motif 12 according to the invention, which is formed by an overlap of a watermark 14 and a crosslinked recess area 16. The watermark 14 represents as a reason the value figure "10", which is surrounded by the recess area 16 configured in the form of a cloud or in the form of a flower. The visual impression of the combination motif is modified during the change between observation in reflected light and in the backlight in a pronounced way, as explained below more exactly.

The combination motifs according to the invention combine the advantageous properties of watermarks that have been tested and have long been known with modern cross-linked laser holes, generated by laser cutting. Depending on the thickness of the local paper inside the watermark, the laser radiation generates continuous cut lines or only non-continuous thinning lines on the paper. As indicated above, the term "notch" in this case represents a generic term for continuous openings or cuts and for non-continuous thinning of the paper, so that a cut-out line can be a cut line or a thinning line.

Due to the dependence on the result of the paper thickness cut, the two safety features, watermark and laser cut interact, and generate a complex combination motif that gives the observer a different visual impression when observing reflected light . The visual effect of the combination pattern 12 in this case far exceeds the effect of a conventional watermark. Also the reticulated recess zone is revalued optically by the combination with the watermark motif. Overall, the security role according to the invention is therefore visually appealing and can also be easily examined by inexperienced people regarding authenticity. In addition, security paper can only be imitated with difficulties by potential counterfeiters due to the necessary synchronization of two security features generated at different stages of papermaking.

As explained below more exactly, the reciprocal influence of the two safety features allows a great variety of variants in terms of the motif of the combination of reflected light and light.

Referring to fig. 2 Figures 2 (a) and (b) first show the two safety features to be combined, watermark 22 and recess area 30 respectively individually. Fig. 2 (a) shows in this case a vision of the security paper 20, in which with an electrotype the value figure "10" of the banknote is applied as a watermark 22. As can be better distinguished in the cross section of fig. 2 (c), the area of the value figure forms a thin point 24 in the paper 20, in which the layer thickness dW is reduced with respect to layer thickness d0 of the area without filigree located outside the thin point 24.

Fig. 2 (b) schematically shows a vision of the recess pattern of the recess area 30, which is formed by a multiplicity of parallel recesses 32 in a line with the silhouette of a cloud. In this case, the recess lines 32 are shown in black in the figure, while the areas 34 that remain unchanged during the subsequent laser cutting are shown in white. By the simplest representation, the exemplary embodiments are described firstly by means of parallel straight recess lines, also when, as explained below in reference to fig. 8, the recess lines can also be curved and / or divergent.

In the exemplary embodiment shown, the lattice lines of the recess lines 32 have a periodic length of 0.75 mm with a cut width of the cut lines of 0.25 mm, however, they are also taken into consideration Other cutting widths and distances according to the desired design.

The depth of cut dA of the recess lines 32 is selected in the exemplary embodiment of fig. 2 so that during laser cutting continuous cutting lines 36 are generated in the area of the thin point 24, however, so that in the area without filigree 26, continuous cutting lines are not generated, but only thinning lines 38 you don't continue Mathematically expressed the depth of cut dA is then selected so that it is valid

d0> dA ≥ dW.

Then the security paper 20 is cut in the area of the watermark 22 in a laser cutting installation according to the specification of the recess pattern of fig. 2 (b) and thus the recess zone 30 overlaps the watermark 22. As shown in fig. 2 (c), in the area of the thin point 24 continuous cutting lines 36 are generated, in the area without filigree 26 non-continuous thinning lines 38.

By overlapping the two security features, four different thickness zones are then created on the security paper 20. In the area without watermark 26, the security paper 20 has thinning lines 38 with a paper thickness dV = d0 - gives. Outside the slimming lines 38, the paper thickness of the area without watermark is without modification of d0. The thin point 24 has a thickness of the paper dW outside the cut lines 36, in the continuous cut lines 36 the thickness of the remaining paper is equal to zero.

The relative paper thicknesses and consequently the light clarity can be predetermined in large areas

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as desired by the depth of cut dA and the thickness of the thin point dW. In this case, according to the design of the combination pattern, the thickness of the remaining paper dV of the thinning lines 38 is greater than, equal to or less than the thickness of the thin point dW.

For example, using dW = 0.2 d0 and dA = 0.3 d0, you can guarantee, on the one hand, a reliable cut of the cut lines 36 at the thin point 24 and at the same time the thickness of the paper dV of the slimming lines dV = 0.7 d0 can be made clearly greater than the thickness of the thin point dW. The slimming lines 38 therefore appear lighter than the thin point 24, but lighter than the area without watermark 26.

On the other hand, it can be guaranteed, for example, by selecting dW = 0.7 d0 and dA = 0.8 d0 both a reliable cut of the cut lines 36 at the thin point 24, as well as the thickness of the dV paper of The slimming lines dV = 0.2 d0 can be made clearly smaller than the thickness of the thin point dW. The slimming lines 38 seem to be lighter, therefore, lighter than the thin point 24, which in turn seems lighter than the area without filigree 26.

Finally, it can be ensured, for example, by selecting dW = 0.4 d0 and dA = 0.6 d0 again a reliable cut of the cut lines 36 at the thin point 24 and at the same time the thickness of the dV paper of The slimming lines dV = 0.4 d0 can be selected equal to the thickness of the thin point dW. The slimming lines 38 therefore seem to be lighted up with the same clarity as the thin point 24 and both appear lighter than the area without filigree 26.

When observing reflected light, that is to say in reflected light, the different thickness of the paper dV, dW or d0 has on the contrary virtually no influence on the visual impression of the paper area. In reflected light, the observer can therefore differentiate only between the continuous lines 36 in which the background becomes visible and the paper areas provided with non-continuous cut lines.

For the illustration fig. 2 (d) shows the appearance of the combination motif 12 generated by observing reflected light, fig. 2 (e) shows the aspect when looking at the light.

When observing reflected light, only the continuous cut lines 36 of its surroundings are highlighted, as explained above and shown in fig. 2 (d). Due to the interaction of the watermark 22 and the cut-off area 30, the cut lines 36 reproduce with their silhouette the value figure "10", given that by laser cutting only continuous cut lines 36 have been generated in the area of the thin point 24 and therefore in the form of the value figure "10".

When the combination motif 12 is shown in the light, it shows a more complex aspect, in which, along with lines 36, the thinned paper points 24 and 38 also stand out against the bottom of the area without filigree 26, as shown in fig. . 2 (e). As explained above, the relative clarity of the thin point 24 and the slimming lines 38 can be broadly adjusted as desired, the two clarities of approximately equal value being selected in the embodiment shown.

The watermark may be formed within the framework of the invention not only by a thin point, but also by a thick point 44 on the security paper, as illustrated by the security paper 40 shown in fig. 3.

As in the representation of fig. 2, Figures 3 (a) and (b) show first of all the two safety features to be combined, watermark 42 and recess area 50 respectively individually. Fig. 3 (a) shows a vision of a security paper 40 containing the value figure "10" in the form of a thick point 44. In the area of the thick point 44 the thickness of layer dW of the paper is increased with respect to the thickness of layer d0 of the area without filigree 46 located outside the thick point 44, as also shown in the cross section of fig. 3 (c).

The recess pattern of the recess zone 50 shown in fig. 3 (b) is formed as in fig. 2 (b) in the form of a cloud of a multiplicity of parallel recesses 52 in the form of lines. The depth of cut dA of the cut-out lines 52 is selected in this case so that during the laser cut the continuous cut lines 56 are generated in the area without filigree, however, so that in the area of the thick point 44 no continuous cutting lines are generated, but only non-continuous thinning lines 58. Mathematically expressed in the exemplary embodiment of fig. 3 the cutting depth dA is therefore selected so that it is valid

dW> dA ≥ d0.

If the security paper 40 is cut in the area of the watermark 42 now in a laser cutting installation according to the specification of the recess pattern of fig. 3 (b), then the recess zone 50 overlaps the watermark 42. In the area without filigree 46 continuous cutting lines 56 are generated by laser cutting, in the area of the thick point 44 thinning lines 58 do not continue, as shown in fig. 3 (c).

Together, by overlapping the two safety features, four thickness zones originate.

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different in the security paper 40. In the area without filigree 46 the security paper 40 has the cut lines 56 with a thickness of the remaining paper of zero, outside the cut lines 56 the thickness of the paper in the area without filigree unmodified is d0. The thick point 44 contains the thinning lines 58 of a remaining wall thickness dV = dW-dA, outside the thinning lines 58 the thickness of the paper paper is dW. Here also the relative paper thicknesses and consequently the clarities of the thick point and thinning lines in the light can be predetermined according to the desire by the depth of cut dA and the thickness of the thick point dW.

For the illustration fig. 3 (d) shows the aspect of the combination motif generated by observing reflected light, fig. 3 (e) shows the aspect when looking at the light.

When observing reflected light, only the continuous cutting lines 56 of its surroundings are also highlighted here, as shown in fig. 3 (d). By the interaction of the thick point 44 with the recess zone 50, the cutting lines 56 reproduce with their outer silhouette the cloud shape of the recess zone 50 and contain inside a zone 44 in the form of the value figure " 10 ”, in which the slimming lines 58 are present but not the continuous cutting lines. Since the slimming lines 58 and the thick point 44 cannot be practically differentiated in reflected light from the area without filigree, the aspect shown in fig. 3 (d).

When the combination motif 12 is shown in the light, it shows a more complex aspect, in which in front of the bottom of the area without filigree 46, the slimming lines 58 as clarifications and the thickened area 44 as darkens become additionally visible, as illustrated in fig. 3 (e).

In fig. 4 shows another embodiment of the invention, showing figures 4 (a) and (b) again the two safety features to be combined, watermark 62 and recess area 70 individually. Fig. 4 (a) shows a vision of security paper 60, which as a watermark 62 contains a dark writing, here the sequence of letters "PL" in the form of thickened paper areas 64. As in the exemplary embodiment of fig. 3 the layer thickness is increased in the area of the thick points 64 with respect to the layer thickness of the area without filigree 66 located outside the thick points 64.

The recess pattern of the recess zone 70 shown in fig. 4 (b) is again formed by a multiplicity of parallel recesses 72 in the form of lines with the outer silhouette of a cloud. Inside, the recess zone 70 also contains the value figure "10" as free areas of recess lines. As in the exemplary embodiment of fig. 3, the depth of cut of the cut-out lines 72 is selected so that during laser cutting continuous cut lines 76 are generated in the area without watermark 66, however, so that in the area of the thick points 64 no continuous cutting lines are generated, but only thinning lines

78. The appearance of the combination motif when observing reflected light is shown in fig. 4 (c), the aspect to be seen in the light in fig. 4 (d).

The realization of the two aspects is produced by the interaction of the different paper thicknesses, as explained in fig. 3.

Fig. 5 shows another embodiment of the invention, in which the recess area 50 shown in fig. 3 (b) is not combined with a watermark 82 on two levels, but with one on several levels.

Fig. 5 (a) shows in this case a vision of a security paper 80 with the watermark 82 on several levels, the watermark 82 presenting in the embodiment example a practically continuous thickness variation and varying the layer thickness between the minimum layer thickness dW, min and a maximum layer thickness dW, max. In practice, the watermark 82 generally represents a portrait, an architectural, technical or natural motif.

Instead of a practically continuous variation in thickness, the watermark can also be configured in a staggered way and have only a few discrete paper thicknesses. The watermark 82 may contain only thinned areas, only thickened areas or, as in the example of embodiment shown, both thinned areas 84 and also thickened areas 88 with respect to the surrounding area without filigree 86.

The recess area 90 shown in fig. 5 (b) corresponds in its shape to the recess area 50 of fig. 3 (b). The cutting depth dA of the recess lines 92 is however selected from dW, min and dW, max

dW, max> dA> dW, min,

so that in thinner partial areas of the watermark 82 cut lines 96 are generated during laser cutting, while thinner lines 98 are generated in thicker partial areas, as shown in fig. 5 (c).

Fig. 5 (d) shows the aspect of the combination motif generated by observing reflected light, fig. 5 (e) the aspect when looking at the light. When observing reflected light, a relatively simple visual aspect is shown, since only the continuous cut lines 96 of its surroundings are highlighted and neither the watermark 82 itself nor the lines can be seen

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of thinning 98. However, the thickness distribution of the paper in the watermark 82 fixes in which parts of the watermark are generated above all cut lines 96, so that the interaction of the two safety features already exists reflected light effect.

When you look at the light, all the complexity of the combination motif becomes visible. Both the multi-level watermark 82 appears with its different clarity levels, as well as the thinning lines 98 with their remaining paper thicknesses of different sizes (fig. 5 (c)) and therefore their equally different clarity.

The embodiments described so far start from the fact that during laser cutting a laser beam with a parallelepiped energy distribution is used

E (x, y) = E0, for –x0 ≤ x ≤ x0 and –y0 ≤ y ≤ y0

E (x, y) = 0 otherwise.

With a similar energy distribution, the width of the cut-out lines is practically independent of the thickness of the local paper. However, in notch lines that are not parallel with respect to one of the axes of the energy distribution, the duration that the laser beam can act on the paper, and therefore also the result of the cut or removal depends on the place of the paper within the distribution of energy.

Therefore, in some variants of the invention it may be recommended to use a cutting laser with an energy distribution in the form of a bull or donut, in which the result of the cut or removal presents only a small dependence in any direction of the cut-out lines. of the place within the energy distribution.

Distributions of energy in the form of a parallelepiped or donut of the laser cutting beam can be generated by appropriate optical elements, for example, with the aid of diffractive optical elements.

Conversely, it is also recommended to use energy distributions with an especially intense dependence on the result of the cutting or removal of the paper site within the energy distribution, such as the Gauss bell-shaped energy distribution 100 shown in the fig. 6. By using a cutting laser with a Gaussian bell-shaped distribution, a dependence on the width of the cut-out lines generated by the thickness of the local paper is produced, such that the width of the cutting or cutting lines Thinning is smaller, the greater the thickness of the local paper. Then, for example, in the case of a large paper thickness the laser energy W only manages to completely cut the paper in a narrow cutting area 102, while at a point with a smaller paper thickness the laser energy exceeds the threshold cutting in a wider 104 cutting area.

This effect can be used in an oriented manner to provide a watermark with different wall thicknesses locally with recess lines with variable width. For the illustration fig. 7 shows the particularity VII of fig. 5 (d) in detail, the laser cutting being performed, unlike the exemplary embodiment of fig. 5, in fig. 7 with a laser beam with 100 energy distribution in the form of a Gaussian bell. In this way, the cutting lines 96 originate in the thinnest paper areas with a wider cutting width 104 and in the thicker paper areas a smaller cutting width 102. In the case of a continuous modification of the thickness of the paper, the width of the cutting lines 96 is also modified continuously, as shown in fig. 7.

The cut-out lines 112 of the cut-out area 110 must not be rectilinear and parallel, as shown in the previous embodiments and in fig. 8 (a). Rather, the recess area 110 may also contain, for example, rectilinear and divergent recess lines 114, as shown in fig. 8 (b), or bending lines 116 curved, equidistant, as shown in fig. 8 (c) or also curved, divergent notch lines 118, as shown in fig. 8 (d).

It is understood that the configurations shown can be combined with each other at will. Then, for example, the divergent and / or curved recess lines of Figures 8 (b) to (d) can be combined with all the described types of watermarks with thin or thick points or they can be generated with a width of cut depending on the thickness of the paper. The cut-out lines of all embodiments can also be provided with a marginal zone modified by laser, as described generally above.

Claims (18)

5 10 fifteen twenty 25 30 35 40 Four. Five E11007948 09-26-2014 1.-Security paper for the manufacture of security and value documents with a watermark that forms a first motif, characterized in that the watermark is superimposed by a recess area that forms a second motif and is formed by at least one recess in the form of lines, generated by the action of a laser radiation on the security paper, so that the superposition of the watermark and the recess area forms a reason for combining the first and second motif, which it presents a visual impression modified to the light with respect to reflected light. 2. Security paper according to claim 1, characterized in that the watermark comprises a thin point with a reduced paper thickness with respect to the environment. 3. Security paper according to claim 1 or 2, characterized in that the watermark comprises a thick point with an increased paper thickness with respect to the environment. 4. Security paper according to at least one of claims 1 to 3, characterized in that the watermark is configured in two or several levels. 5. Security paper according to at least one of claims 1 to 4, characterized in that the first motif of the watermark represents a portrait, an architectural, technical or natural motif, or a succession of alphanumeric characters, in particular a figure of value 6. Security paper according to at least one of claims 1 to 5, characterized in that the first and second motives represent information referred to each other or complementary to each other. 7. Security paper according to at least one of claims 1 to 6, characterized in that the recess area is formed by a multiplicity of recesses in the form of lines in the security paper. 8. Security paper according to at least one of claims 1 to 7, characterized in that the recesses in the form of lines comprise continuous cutting lines. 9. Security paper according to at least one of claims 1 to 8, characterized in that the line-shaped recesses comprise non-continuous thinning lines through the security paper. 10. Security paper according to at least one of claims 1 to 9, characterized in that the recesses in the form of lines comprise cut lines and slimming lines that are connected to each other without bending. 11. Security paper according to at least one of claims 1 to 10, characterized in that the recess area is completely disposed inside the watermark. 12. Security paper according to at least one of claims 1 to 11, characterized in that the recess area is formed by a multiplicity of straight, parallel or divergent recesses, in the form of lines. 13. Security paper according to at least one of claims 1 to 11, characterized in that the recess area is formed by a multiplicity of curved, equidistant or divergent recesses, in the form of lines. 14. Security paper according to at least one of claims 1 to 13, characterized in that the recesses in the form of lines have a width between 0.05 mm and 1 mm, in particular between 0.1 mm and 0.4 mm. 15. Security paper according to at least one of claims 1 to 14, characterized in that the security paper is provided at least in a partial area with a laser modifiable marking substance, and because the line-shaped recesses have a this partial zone a marginal zone modified by the action of a laser radiation, preferably because the security paper is provided in the partial zone with a marking substance whose visible color can be modified by the action of the laser radiation, and because the recesses in the form of lines they present in this partial zone a marginal colored zone. 16. Process for the manufacture of a security paper according to one of claims 1 to 15, wherein a security paper is provided with a watermark that forms a first motif, and the watermark is superimposed by a recess zone, which forms a second motif and is formed by a multiplicity of recesses in the form of lines, generated by the action of a laser radiation on the security paper, so that the overlap of the watermark and the area of Notch forms a combination motif of the first and second motif, which presents a visual impression modified to the light with respect to reflected light. 17. Method according to claim 16, characterized in that the line-shaped recesses are generated by laser application with an infrared laser, preferably with a CO2 laser. 9 E11007948 09-26-2014 18. Method according to claim 16 or 17, characterized in that the security paper is provided in at least a partial area of a laser modifiable marking substance, so that the line-shaped recesses are modified in this partial area by the action of the laser radiation in its marginal zone, preferably because the security paper is provided in the partial zone of a marking substance, whose visible color can be modified by the action of the laser radiation, and because the recesses in the form of Lines are provided in this partial zone by the action of laser radiation with a marginal colored zone. 10