EP2865625A1 - Method and device for producing a safety element - Google Patents

Abstract

The invention relates to a method for producing a security element for documents of value, bank notes or the like, comprising the steps of: providing a web (1) which contains a plurality of first components of the security element for producing a plurality of the security element, and conveying the web (1 ) along a path (S) and applying a plurality of second components of the security element to the web (1) at the end of the path (S), the web in the path (S) by means of an adjustable draw roll (4) having a biaxial Has curved lateral surface is stretched differently across a web longitudinal axis, to set a register position between the first and second components.

Description

The invention relates to a method for producing a security element for documents of value, banknotes or the like, comprising the steps of: providing a web which contains a plurality of first components of the security element for producing a plurality of the security element, and conveying the web along a route, and Applying a plurality of second components of the security element to the web at the end of the route.

The invention further relates to an apparatus for producing a security element for documents of value, bank notes or the like, comprising: a conveyor for conveying a web, which contains a plurality of first components of the security element, along a route and at the end to produce a plurality of the security element the path arranged applicator for applying a plurality of second components of the security element on the web.

To improve the security against forgery of value documents, security elements are increasingly used that consist of several constituents, for example of several layers. An example of such a security element are so-called moire magnifiers, in which microstructures and microlenses are applied one above the other. The microstructures lie on a substrate in a well-defined grid and the microlenses must be formed with respect to raster width and position of this defined grid in a precisely prescribed arrangement to the microstructures. The register between these two components must be followed very closely. This is technically complex, both when the first and second components are formed on different webs that need to be joined together, as well as when the first and second components are produced by successive printing and / or embossing processes. In a generic method or a generic device, the application of the second components in exact register position or at least under exact compliance with the desired length ratios to the first components that are already present on the track, done.

The generic WO 2009/083149 A2 deals with this problem area. It provides for the promotion of a web prior to the application of the second components before the use of a so-called Einschwenkwalze, which is made depending on the adjustment obliquely to the conveying direction of the web. In this way, the web is tilted with respect to the axis of a subsequent printing or embossing cylinder to the register layer between the first constituents that are already present on the web, and the second components to be applied with the printing or embossing cylinder through the cylinder jacket surface of the corresponding cylinder are set to adjust. The principle of WO 2009/083149 A2 has proved its worth.

The development of security elements, which are further improved in terms of their security against counterfeiting, have further increased the requirements for register accuracy between the first and second components. In addition, you want to use the widest possible paths in terms of efficient production. In addition, material mixtures are increasingly used for security elements, that is, for example, the combination of a plastic web, which carries the plurality of first components of the security element, with a paper web, which provides the plurality of second components. These material mixtures Manufacturing technology are difficult to control due to different thermal expansions, warming when conveying a web, etc., as regards the register accuracy when bringing together the different materials. Finally, one would like to choose the production speed of a web as high as possible in order to achieve a high throughput.

The invention is therefore based on the object, a method and an apparatus of the type mentioned in such a way that the register accuracy between the existing on the web first components and the application of the second components can be set as accurately as possible.

1. a) Bereitstellen einer Bahn, die zur Herstellung einer Vielzahl des Sicherheitselementes eine Vielzahl an ersten Bestandteilen des Sicherheitselementes enthält, und Fördern der Bahn längs einer Strecke, und
2. b) Aufbringen einer Vielzahl an zweiten Bestandteilen des Sicherheitselementes auf die Bahn am Ende der Strecke, wobei
3. c) die Bahn in der Strecke mittels einer verstellbaren Streckwalze, die eine zweiachsig gekrümmte Mantelfläche aufweist, quer zu einer Bahnlängsachse unterschiedlich in Längs- und/ oder Querrichtung gedehnt wird, um eine Registerlage zwischen ersten und zweiten Bestandteilen einzustellen und/ oder bestimmte Längenverhältnisse zwischen ersten und zweiten Bestandteilen einzuhalten.

This object is achieved according to the invention with a method for producing a security element for value documents, banknotes or the like, which comprises the following steps:

1. a) providing a web which contains a plurality of first components of the security element for producing a plurality of the security element, and conveying the web along a route, and
2. b) applying a plurality of second components of the security element to the web at the end of the route, wherein
3. c) the web in the stretch is stretched differently in the longitudinal and / or transverse direction transversely to a web longitudinal axis by means of an adjustable draw roll, which has a biaxially curved lateral surface, about a register position between first and second components adjust and / or maintain certain length ratios between the first and second components.

1. a) eine Fördereinrichtung zum Fördern einer Bahn, die zur Herstellung einer Vielzahl des Sicherheitselementes eine Vielzahl an ersten Bestandteilen des Sicherheitselementes enthält, längs einer Strecke, und
2. b) eine am Ende der Strecke angeordnete Aufbringeinrichtung zum Aufbringen einer Vielzahl an zweiten Bestandteilen des Sicherheitselementes auf die Bahn, wobei
3. c) die Vorrichtung in der Strecke eine verstellbare Streckwalze aufweist, die eine zweiachsig gekrümmte Mantelfläche aufweist, um die Bahn quer zu einer Bahnlängsachse unterschiedlich in Längs- und/ oder Querrichtung zu dehnen und eine Registerlage zwischen ersten und zweiten Bestandteilen einzustellen und/ oder bestimmte Längenverhältnisse zwischen ersten und zweiten Bestandteilen einzuhalten.

The object is further achieved with an apparatus for producing a security element for value documents, banknotes or the like, which comprises:

1. a) a conveyor for conveying a web, which contains a plurality of first components of the security element, along a route, and for producing a plurality of the security element
2. b) an applicator arranged at the end of the track for applying a plurality of second components of the security element to the web, wherein
3. c) the device has an adjustable drafting roller in the path, which has a biaxially curved lateral surface in order to stretch the web transversely to a web longitudinal axis differently in the longitudinal and / or transverse direction and to set a register position between first and second components and / or certain aspect ratios between the first and second components.

According to the invention, a draw roll is used which has a two-dimensionally curved lateral surface. This draw roll makes it possible to adjust the tension or tension in the middle of the web with respect to the edges, for example to reduce (or preferential) or to increase the tension in the middle of the web. In this way, the tension conditions in the web can be adjusted so that the application of the plurality of second components of the security element in the register to the first components happening on the track. The web can be further processed, ie the end of the route is usually not the end of the processing plant.

With regard to the lateral surface, a biaxial curvature is understood to mean that the lateral surface in each case has a curvature in two sectional planes which are not parallel to one another, ie may be orthogonal in particular. The concept of biaxial curvature is therefore identical in the underlying understanding with the concept of a two-dimensionally curved surface in the mathematical sense. The curvature in each section plane is not limited to satisfying a circular geometry. Rather, arbitrarily shaped lateral surfaces also fall under the term biaxial or two-dimensional curvature. The biaxially curved lateral surface of the draw roll causes the draw roll is no longer a pure circular cylinder in the mathematical sense. In the mathematical sense, a cylindrical surface is known to be obtained when moving a closed trajectory (the so-called generator) along a straight line. Conventional rolls have as a generator a circle which is displaced along a straight line, they are circular cylinders. The draw roll also has a circle as a generator in preferred embodiments, which is now displaced not along a straight line, but along a curved trajectory. The circle as a generator is responsible for a uniaxial curvature, the curved trajectory, along which the circle is moved to generate the lateral surface, causes a further axis of curvature.

The approach of the present invention, when conveying the web in the processing machine, allows the tension on the web to be adjusted to compensate for distortions across the width of the web. As a result, when applying the second components or more generally in the successive coordinated execution of processing steps on the web avoiding distortions that would lead to the production of rejects. The processing steps may include, for example, the generation of a desired overall motif in which a first print layer is applied to the web in a first processing step. This can be the provision of the web to be conveyed or in the device a processing device located before the start of the route. The print layer can be, for example, a motif grid for a moiré magnifier, a modulo mapper or a tilted image with or without magnification effect. In the second processing step, the application of the second components. This may be, for example, the application of a microlens layer with a microlens grid, which has to stand in a predetermined relationship to the first motif grid in order to achieve a desired overall motif. The draw roll according to the invention makes it possible to compensate for distortions across the width of the web, ie transversely to the conveying direction. Disturbances of one of the two motif grids and disturbances of the overall motive are avoided. The order in which the first and second components are applied can be reversed.

Since the amount of cross-machine directional distortion generally increases with the width of the web, the solution of the invention achieves a particular economics benefit in that wider webs can be used which would otherwise be required for conventional manufacturing apparatus / methods due to distortions caused by, for example, the conventional Conveying devices and / or caused by inhomogeneities in the material of the web or could be made worse, would not be suitable.

The device can at the beginning of the route a processing device, for. B. a printing unit, which generates the first components on the web.

In a preferred embodiment, the incoming film already contains the first constituents. Then the film passes through a printing unit, in which a UV-curable medium (embossing lacquer) is applied. Subsequently, the web is conveyed to an embossing station, which generates the second components by embossing and UV irradiation. There, the elongation of the incoming film must be corrected so that the second components harmonize as desired with the first components in terms of position and dimension. Preferably, the correction takes place immediately before the embossing tool. Instead of a UV-curable medium and a thermoplastic medium or a thermoplastic deformable film can be used.

The processing steps, in particular the production of the first and second components, can take place both on one and the same side of the web, as well as on different sides.

A positive side effect of the device according to the invention or of the method according to the invention is that the requirement for the film quality with regard to stretching at different tension or different voltages is markedly reduced. It is no longer absolutely necessary to use films which have a very homogeneous expansion behavior, but can even out a material-related inhomogeneous expansion in the case of film material which exhibits a comparatively inhomogeneous expansion behavior by suitably setting the draw roll.

As a stretching roller a variety of designs come into question. A particularly preferred design is a roller which has the shape of a curved circular cylinder. It is therefore a circular cylinder in and of itself cylindrical, the term "circular cylinder" being understood here in the mathematical sense. He describes a cylinder, which is obtained by moving a circle, which is the generator in the mathematical sense, along an axis. By bending this axis, the draw roll provided according to the invention with a two-dimensionally curved lateral surface is obtained. In order to adjust the stretching and tension conditions in the web before applying the plurality of second components of the security element, in one embodiment, the bending of the circular cylindrical roller, that is, the deflection of the axis of the roller adjustable. In a preferred embodiment, the curved roller is additionally rotatably mounted at both ends such that the plane of the maximum bending can be inclined relative to the plane of the continuous film web (pivotable roller). Here it is possible to change the direction in which the maximum bend points. At the same time, it is expedient to make the outside of the web to be conveyed end points of the roller as adjustable as this WO 2009/083149 A2 for a conventional roller already describes. The disclosure of this document is therefore fully incorporated in this regard.

The application of the plurality of second constituents of the security element can in a first embodiment be carried out by providing an additional web containing the plurality of second constituents and connecting it to the web. Here, the invention is particularly advantageous in cases where the additional web is made of a different material than the web. For example, different strains of the material mix plastic web / paper web can be well balanced. In the device In this embodiment, an application device is provided which has a laminating unit, and a supply device feeds the additional path to the laminating unit. In a further embodiment, the plurality of second constituents are applied by means of a printing or embossing process. The device then has as an applicator on a printing or embossing. In the manufacturing process, the plurality of second components is applied at the end of the route through a printing or embossing cylinder, through which the web is guided.

A further variant for the roller with a two-dimensionally curved lateral surface is a so-called S-roll: it contains in its interior a plurality of elements with the aid of which the extent of the sheathing at the respective point can be influenced. It has the advantage that the shape of the roller can be made very flexible, in particular can be more complicated than a simple bend.

Instead of a curved circular cylinder whose bending and optionally also pivoting position are adjustable, it is also possible to use a cylinder which has a convex or concave shape in cross-section, ie is barrel-shaped or spindle-shaped. Here, the curvature of the lateral surface is not changeable, but one can use a cylinder whose basic shape is adapted to normal conditions with respect to the stretching of the web. Alternative lateral surfaces are represented by cones in the middle or else considerably more complicated shapes, which can be realized by milling or turning and which influence the expansion of the film or the conveyed medium in the desired manner. Unlike a curved circular cylinder such rollers are not continuously deformed during operation, ie during rotation. The danger of a Material fatigue is lower or simpler materials for the roller can be used.

In a further embodiment, the roller used has a sheath which influences the adhesion or friction to the medium used. Local adhesion or frictional properties varying over the length of the roll can also affect the elongation of the conveyed medium in the desired sense. With a positive result, a grooving of a plastic coating of a draw roll was tested. An alternative to producing a variable adhesion profile is to use a locally applicable electrostatic charge on the roller.

In a particularly preferred embodiment, the registration between first and second components is continuously monitored during operation and the position of the draw roller is adjusted accordingly within the scope of a regulation. The monitoring can be done after the application of the plurality of second components of the security element. This measurement can be carried out particularly simply, but has the disadvantage that errors in the register between the first and second components are only recognized if deviations from the ideal case have already occurred and are irreparably present in the product. There is therefore provided a further embodiment, which determines by means of a measuring device, the position of the first components at different locations across the web before applying the second components and adjusts the position of the draw roller depending on the determined position. The measuring device can be upstream of the draw roll. For this purpose, one only has to determine in advance the effect of a certain draw roll position with respect to a positional shift of the first components due to an elongation of the web which causes the draw roll. Then in this embodiment form Depending on the determined position of the first constituents in the current operation, the draw roll set appropriately.

In another embodiment, the measuring device is downstream of the draw roll. Here, the draw roll can be adjusted in the sense of a regulation to set the position of the first components predetermined. Unlike when measuring after applying the second constituents, it is still possible to react here if there is a misplacement of the first constituents, since an adjustment of the draw roll on the entire web path acts until the second constituents are applied. Measuring between the draw roll and the end of the stretch, d. H. Thus, at the point where the application of the second constituents begins, there is the advantage of avoiding the production of rejects, and nevertheless a relatively simple control can be carried out whose manipulated variable is the adjustment of the draw roll. For this embodiment, the invention comprises a position detector device, which is arranged on the track and is designed to determine a position of the first components. Furthermore, the device comprises a corresponding control device which controls the adjustable draw roller, in particular in the form of a control.

In embodiments which connect two or more webs, measuring devices are expediently located on all webs.

For the adjustment of the draw roll all suitable mechanical means come into question, for example, in the WO 2009/083149 A2 are called, such as a spindle, hydraulic, pneumatic, electric servomotor, etc., which act on the ends of the draw roll and / or adjust the bending and / or Einschwenkposition the lateral surface of the draw roll.

• Bevorzugterweise wird ein vergrößertes Moire-Bild mittels einer Bilderkennung erfasst, die die Größe des Moire-Bildes und/ oder dessen Verzerrung ermittelt und zur Basis der Steuerung der Streckwalze macht. Ein vergrößertes Moire-Bild wird z. B. mittels einer Kamera beobachtet, der aktuelle Vergrößerungsfaktor und die Abweichung vom beabsichtigten Vergrößerungsfaktor ermittelt und damit die Einstellung der Streckwalze derart beeinflusst, dass sich der Vergrößerungsfaktor wieder in Richtung Sollwert bewegt, und zwar im Idealfall über die ganze Bahnbreite.

With regard to the measurement of the position of the first constituents, for a security element comprising a Moire Magnifier, the following applies to the position detection:

• Preferably, an enlarged moiré image is detected by means of an image recognition which determines the size of the moiré image and / or its distortion and makes it the basis of the control of the draw roller. An enlarged Moire image is z. B. observed by means of a camera, the current magnification factor and the deviation from the intended magnification factor determined and thus affects the setting of the draw roller such that the magnification factor moves back towards the target value, ideally over the entire web width.

If z. For example, if a moiré magnification of 200 is sought, where the magnified image appears to be lower than the viewing plane for the viewer, then the microstructure is required to be 0.5% smaller than the microlens grid across and along the film transport direction the microlens grid. So z. B. according to the embossing the microlens grid by 0.5% larger than the microimage grid. In the first operation - or in a first processing station - the microlenses are produced (preferably by embossing in transparent lacquer). If a maladaptation between the microstructures and the microlenses is determined by the camera and downstream image analysis during the second operation - the production of the microstructures, this is counteracted by an automatic readjustment of the draw roll by increasing the pre-stretching of the film until the desired registration is restored , As a result, the material width, ie the width of the web section with correctly enlarged moire structures, is increased as far as possible over the entire width of the web.

In known microlens and microimage raster geometry can be determined from the deviation between the enlarged nominal image and the real visible enlarged moire image, which raster width difference and which angle is set between microlens and Mikrostrukturraster. After comparing the actual and setpoint, the draw roller can be readjusted.

Very high magnification factors can also be generated by means of microlenses and microimages and a suitable grid arrangement of the two structures relative to one another. It can z. For example, moiré images may be produced which appear to be above or below the film plane by more than 1 cm and have a size of several millimeters. Moire images of this kind are very well suited for security elements because of their size and the striking depth or height effect. For a security element, however, there is always very limited space available on a banknote. For example, in a security thread, which typically has a width of 2 mm to 6 mm, a well-perceived motif with several millimeters in size should be positioned centrally in the middle of the thread. In a foil patch with a typical lateral extent of approx. 20 mm, a Moire image with approx. 10 mm can be positioned so that it appears centrally on the patch with a vertical viewing angle. With moire motifs as large as this, care must be taken to ensure that the enlarged motifs appear on all value documents of similar size and position in the slide element. This is very difficult to accomplish in the production because, with a lateral shift of the microlens to the microstructure grid of only one screen pitch (typically 10 μm to 50 μm), the magnified motif already shifts laterally by a distance resulting from microstructure grid size times magnification factor and therefore in the range of several millimeters. This implies, conversely, In the case of typical Moire magnifiers, a positional accuracy of a large Moire image can only be achieved if the microimages are controlled with a position accuracy of a few micrometers below the microlenses. As an example, assume microlenses and microimages with a pitch of 30 microns and a desired enlarged image of 9 mm. The magnification factor here is 300. If this enlarged image may deviate from its nominal position on the film by ± 2 mm, this means that the micro image under the microlens must comply with a lateral positional tolerance of 6.7 μm. Preferably, therefore, the enlarged moiré image itself is used. The size and the position of the moiré image are recorded by means of a camera and image evaluation, and with this information the draw roller in the feed of the web is adjusted so that the enlarged moiré image is at the desired position on the film. The controlled system moves only in the range of 1 .mu.m to 50 .mu.m.

In a simplified embodiment, the absolute positioning accuracy is not set, but the relative aspect ratios are adjusted to achieve the proper magnification.

The concept of position detection of the first components thus also includes the position detection of the combination of first and second components and in particular the evaluation of a moiré image with regard to magnification and / or distortion. From the position detection is preferably a control variable for the retraction position or angle of the draw roll. Now the moire motifs can be quite different in type and size for different applications. The evaluation of different size and shape variable motifs in terms of size and location is for image analysis always difficult. Therefore, adaptive systems are preferably first trained on the respective motif.

In a preferred development, control motifs are provided on the web and possibly on the additional web, which are particularly preferably evaluated on the film edges and / or on the film width in size and optionally position of the camera detection and evaluation tool and thus the respectively necessary readjustment the film stretching be initiated. By way of example, as a simple control motif, a stripe design of alternating light and dark stripes in and perpendicular to the film running direction is mentioned. The strips ideally have the same or a slightly different periodicity compared to the microlens grid. This stripe design allows tracing distortions to be detected by detecting the moire magnified stripes, as well as tilting between microlens and microstructure patterns by skewing the magnified stripes. If necessary, such a control motif could be arranged at several positions across the width of the film (eg left edge, right edge and in the middle). It could be arranged continuously over the film longitudinal direction or as a repetitive motif along the film. It could thus provide the information to correct both the film stretching and a tilt of the film. Such a control motif would be the same for all Moire Magnifier films. The advantage here is that the image acquisition system only needs to be trained on the recognition and evaluation of this one control motif.

It may also be useful to use different microlens rasters in the control motifs of the image motif. It is apparent from the prior art that the sensitivity of the enlarged motifs to angle errors between microlens and microimage grid with increasing magnification increases. Therefore, it may make sense to choose a microlens and microimage grid with very small feature size and high magnification as a control. The sensitivity of the control motif to raster width changes and angular errors between microlens and microstructure is then very high and deviations from the setpoints can be detected very accurately.

Depending on which moire effect is desired and how the associated microlens and Mikrostrukturrasters are applied to the embossing / printing tools at the respective operations, the type of readjustment of film stretching or orientation by adjustment of the draw roll in case of deviations from the standard form, size or position of the magnified moire image look very different. Specifically, this means that z. B. in a moire magnifier with orthoparallaktischem motion effect, in which the magnification results from a rotation between Mikrolinsen- and Mikrostrukturraster, a wrong magnification on the correction of the angle of the incoming film web is corrected.

Fig. 1

eine erfindungsgemäße Prägemaschine mit Prägewerkzeug und Streckwalze, wobei in
Fig. 1a in Seitenansicht,
Fig. 1b in Draufsicht, d.h. von rechts in Fig. 1a,
Fig. 1c eine Seitenansicht der Streckwalze, bezogen auf Fig. 1a von oben, zeigen,

Fig. 2

die Funktionsweise einer erfindungsgemäßen Prägemaschine, wobei
Fig. 2a eine Stellung mit Verkippung der Streckwalze,
Fig. 2b eine Stellung ohne Verkippung der Streckwalze,
Fig. 2c eine Stellung mit Verkippung der Streckwalze zeigen, und

Fig. 3

eine Ansicht ähnlich der Fig. 1a für eine weitere Ausführungsform.

In a preferred embodiment of the invention, the position of the first components of the web is checked by control elements are provided on the web, which are provided distributed over the width of the web. There are thus measuring points which are distributed over the width of the web at which the position determination takes place. The draw roll is then adjusted so that the control points are at certain locations, ie traces of the web. Due to the adjustable draw roller with biaxially curved lateral surface, the curvature can be varied during the adjustment. The advantages of the invention and various preferred embodiments of the invention will be explained with reference to the following examples and additional figures. In detail, show schematically:

Fig. 1

an embossing machine according to the invention with embossing tool and draw roll, wherein in
Fig. 1a in side view,
Fig. 1b in plan view, ie from the right in Fig. 1a .
Fig. 1c a side view of the draw roll, based on Fig. 1a from above, show

Fig. 2

the operation of an embossing machine according to the invention, wherein
Fig. 2a a position with tilting of the draw roll,
Fig. 2b a position without tilting the draw roll,
Fig. 2c show a position with tilting of the draw roll, and

Fig. 3

a view similar to the one Fig. 1a for another embodiment.

For the sake of clarity, the embodiments described in the following examples are reduced to the essential core information. The illustrations in the figures are highly schematic and do not reflect the realities. Above all, the proportions shown in the figures do not correspond to the conditions present in reality and serve exclusively for the sake of clarity.

Fig. 1a shows a side view of an embossing machine with an embossing unit in the form of an embossing cylinder 3 and a draw roller 4. The embossing machine leads a web 1 of an endless film in the conveying direction 2 along a distance S via the draw roller 4 to the embossing to.

The web 1 contains first constituents of a security element, for example printed microstructure information. The first ingredients are supplemented with second ingredients to form a security element. The second constituents can be, for example, embossed structures, in particular microlens structures, which, together with the embossed structures, realize a moire magnifier as a security element. The first components are not shown on the lane 1 for the sake of simplicity.

By a counter-pressure roller 5 and a tension roller 6, the endless film is pressed against the embossing cylinder 3, that the structures to be embossed are imaged on the web 1. The imprint of structures in this embodiment is the application of second components of the security element. Of course, other processing steps can be carried out in other embodiments, for example, the lamination of a film (see. Fig. 3 ). The embossing is then z. B. replaced by a corresponding laminating. As soon as reference is made below to the use of a stamping mill or its elements, this refers only by way of example to one of several exemplary embodiments, which may well use other apparatus and methods for applying the first and / or second components.

The web 1 wraps around the embossing cylinder 3 in a predetermined angular range of z. B. 180 °.

The effect of the draw roll 4 is best at high wrap. Therefore, the wrap of the draw roll can also be increased at the expense of the wrap of the embossing roll compared to designs without draw roll 4.

This is followed by curing of the film of the web 1. In this case, the film is irradiated with UV radiation, for example, so that an embossing lacquer applied to the film is cured and thus the microstructure elements transferred in the embossing machine are "frozen" firmly into the embossing lacquer.

Following the embossing process, the web 1 is fed via a deflection roller for further processing. For example, the endless film can be rewound onto a roll or cut to length or cut and stacked in the form of individual sheets.

The draw roll 4 is on one side, or preferably according to FIG Fig. 1b mounted on both sides, rotatable or pivotable. There is (each) a joint around which the draw roller 4 can be pivoted. On its other side, the draw roller 4 is suspended equally. Here, for example, a hydraulic cylinder, a lever mechanism or a spindle acts on a suspension and shifts it in any spatial directions, for example up or down, as the arrows in Fig. 1b Show.

Fig. 1c shows the draw roll 4 in a view based on the Fig. 1a done from above. The draw roll 4 has a roll body 14 which extends along an axis 15. This is unlike conventional rollers not straight, but curved. The curvature is achieved in that the ends of the roller 4 are guided in a pillow block 16 and an abutment 17, which distort the roller in the curved shape. The roller body 14 has a biaxially curved lateral surface due to this curvature. The first curvature corresponds to that of a normal cylinder axis, ie in a section perpendicular to the axis 15, the lateral surface is circular, as well Fig. 1a shows. In the axis 15 contained section, the lateral surface is arcuate, such as Fig. 1c shows. Through this form of Stretching roller 4 can be compensated for a distortion of the web 1 transverse to the conveying direction 2.

The pillow block 16 and the anvil 17 are adjustable, as indicated by an arrow 19 in Fig. 1c is illustrated schematically. The roller rotates about its curved axis 15 (arrow 18). By adjusting the curvature of the axis 15 of the draw roll 4 can be adjusted on the one hand. Fig. 1c shows an example also a stronger curvature (dashed line). On the other hand, the angle between a plane in which the axis 15 has the maximum curvature, and the plane in which the web 1 is conveyed, can be adjusted. The draw roller 4 can thus be pivoted. In Fig. 1c In addition, such an adjustment is also shown (representation with 2-point 3-dash line). In the in Fig. 1b shown state, this angle is 90 °, which is why in the plan view of Fig. 1b the axis 15 does not appear curved. Regardless of the adjustment of the degree of curvature and the angle which exists between the plane with maximum axis curvature and the conveying plane of the web 1, the draw roller 4, as described Fig. 1b has already been explained and subsequently based on the Fig. 2 will be described, also be tilted.

This tilting of the draw roll 4 is schematically shown in FIG Fig. 2 shown. For a better overview, the draw roller 4 is shown there as a line and the untilted position is shown in dashed lines. Fig. 2b shows the initial state, ie the non-tilted drafting roller 4, whose axis of rotation in plan view of Fig. 2 thus is parallel to the axis of rotation of the embossing cylinder 3. Embossed structures 10, which are applied by the embossing cylinder 3 on the endless foil, are aligned parallel to a print motif 9. If the draw roller 4 according to Fig. 2a tilted down, there is an overstretching of the continuous film to the right, based on the direction of the endless film. Due to the curvature of the axis 15, the overstretching does not increase evenly towards the edge, whereby distortions transversely to the conveying direction 2 are compensated.

Fig. 3 shows a further embodiment of the invention in a view similar to the Fig. 1a , Here is the stamping mill that is in the Fig. 1a formed by the elements 3, 5 and 6, replaced by a Kaschierwerk 11, which laminates on the web 1, which carries the first components of the security element to be generated, an additional web 12, which carries second components of the security element. In order to achieve the correct register position or the correct length ratios between the first and second components in this process of connecting the web 1 with the additional web 12, the draw roll 4 is in turn suitably adjusted. In Fig. 3 are purely exemplary two drafting rollers 4 drawn, which act on two routes S. This makes a particularly exact adjustment possible. Of course, depending on the requirement, only one section S can be provided with the draw roller 4.

Fig. 3 shows by way of example further an optional measuring device 13b for measuring the position of the first components on the web 1 and optionally also the second components on the additional web 12. A similar measuring device 13b can also be used in an embodiment with embossing, z. B. in the construction according to Fig. 1 come into use. The same applies to the in Fig. 3 also registered control device 13a, which performs the already mentioned in the general part of the description scheme for adjusting the drafting roller (s) 4.

LIST OF REFERENCE NUMBERS

1

train

2

conveying direction

3

embossing cylinders

4

stretching roll

5

Backing roll

6

pulling roller

7

joint

8th

suspension

9

print motif

10

embossed structures

11

laminating

12

supplementary track

13a

measuring device

13b

control device

14

roller body

15

axis

16

Plummer

17

thrust bearing

18, 19

swivel axis

20

shift

S

route

Claims (14)

Method for producing a security element for value documents, banknotes or the like, comprising the following steps: a) providing a web (1) containing a plurality of first components of the security element for producing a plurality of the security element, and conveying the web (1) along a distance (S) and b) applying a plurality of second components of the security element to the web (1) at the end of the route (S), characterized in that c) the web in the stretch is stretched differently across a web longitudinal axis by means of an adjustable draw roll (4) having a biaxially curved lateral surface to set a registration between first and second components. A method according to claim 1, characterized in that a draw roll (4) is used with adjustable curvature of the lateral surface. A method according to claim 1, characterized in that an additional web (12) containing the plurality of second constituents is provided and connected in step b) to the web (1). A method according to claim 1 or 2, characterized in that in step b) the web (1) at the end of the distance (S) by a printing or embossing unit (3, 5, 6) is guided to apply the plurality of second components , Method according to one of the preceding claims, characterized in that the draw roll (4) has the shape of a bent cylinder, the bend of which is preferably adjustable, or has a convex or concave shape in longitudinal section. Method according to one of the above claims, characterized in that a plane of the strongest curvature of the lateral surface relative to the web (1) can be tilted. Method according to one of the above claims, characterized in that on the path (S) a position of the first and / or second components across the web (1) determined and the adjustable drafting roller (4) is adjusted depending on the determined position, preferably under a scheme. Device for producing a security element for value documents, banknotes or the like, comprising: a) a conveying device for conveying a web (1), which contains a plurality of first components of the security element along a route (S) and to produce a plurality of the security element b) an application device (3, 5, 6, 11) arranged at the end of the path (S) for applying a multiplicity of second components of the security element to the web (1), characterized in that c) the device in the path (S) comprises an adjustable draw roll (4) having a biaxially curved lateral surface for differently stretching the web (1) transversely to a web longitudinal axis and for establishing a registration between first and second components. Apparatus according to claim 8, characterized in that the draw roll (4) has a lateral surface with adjustable curvature. Apparatus according to claim 8 or 9, characterized in that the applicator comprises a laminating unit (11) and an auxiliary web feeder (12) containing the plurality of second constituents. Apparatus according to claim 8 or 9, characterized in that the application device has a printing or embossing unit (3, 5, 6). Device according to one of claims 8 to 11, characterized in that the draw roller (4) has the shape of a bent cylinder, the bending of which is preferably adjustable, or in longitudinal section has a convex or concave shape. Device according to one of claims 8 to 12, characterized in that a plane of the strongest curvature of the lateral surface relative to the web (1) is tilted. Device according to one of claims 8 to 13, characterized in that the device comprises a position detector device (13a), which is arranged on the path (S) and for determining a position of the first components is formed transversely on the web (1).

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