EP2860043B1 - Method of forming a watermark - Google Patents

Description

The present invention describes a method for producing a watermark as a security feature for a portable data carrier.

Watermarks are known from the prior art, which are used as a security feature for banknotes. In this case, a thickness of a paper layer is changed according to a gray value of an image in order to achieve an optical impression of a watermark in the viewer.

Furthermore, the use of a three-dimensional pressure is known from the prior art.

The problem is that the watermarks known from the banknote sector are not suitable for the production of portable data carriers, e.g. Smart cards, SIM cards, credit cards, health insurance cards, passports with chip, etc. are suitable.

Furthermore, the watermarks used in the banknote area are always the same for a series or a production lot. An individualization for each individual banknote is not provided.

EP 2 441 593 A1 discloses an achromatic security element for security documents, such as banknotes, smart cards, identity documents, and the like, comprising a thermoplastic or radiation-curable polymer layer, which layer is embossed with diffusely reflecting microstructures on the order of 1 to 100 microns.

EP 2172 336 A1 describes layer structures made of thermoplastic layers containing printed watermarks as security features.

GB 2 346 111 A discloses security documents, such as banknotes, which are encoded with printed identification features that, while not visible to the human eye, are recognizable by machine read-in to allow for document authorization or counterfeit protection.

Based on the disadvantages of the prior art, the object of the present invention is to find a solution which overcomes the disadvantages of the prior art.

The object of the invention is achieved by the independent claim. Advantageous embodiments are described in the subclaims.

To solve the problem, the invention discloses a method for producing a water mark as a security feature for a portable data carrier with the features of claim 1.

An advantageous embodiment is that a brightness value is determined for at least one point of an image in accordance with an adjustable local resolution. Depending on the technically possible spatial resolution of the image, an image may have more or fewer pixels. Furthermore, such a degree of detail of the image can be determined.

A further advantageous exemplary embodiment is that a layer thickness of the watermark to be printed is determined for at least one brightness value at the location of the associated point of the image.

Another advantageous embodiment is that the watermark is printed by means of an at least partially opaque material.

Another advantageous embodiment is that at least one security feature is introduced into the material for printing the watermark. As a security feature, all known or suitable security features in question, as they are known for example from banknote printing or ID smart card and passport production, such as fluorescent or luminescent features or microparticles with a label.

Another advantageous embodiment is that at least one layer is applied to the printed watermark to produce a planar surface.

Another advantageous embodiment is that for the at least one layer to produce a planar surface, an at least partially transparent material is used. It is particularly advantageous if this material is more transparent than the material forming the watermark.

Another advantageous embodiment is that a clear coat is used for the layer to produce a flat surface.

Another advantageous embodiment is that at least one pigment is introduced into the layer to produce a planar surface to prevent scanning of the structure of the watermark.

A further advantageous embodiment is that at least one security feature is introduced into the layer to produce a flat surface. As a security feature, all known or suitable security features come into question, such as e.g. from banknote printing or ID smart card and passport manufacture, e.g. fluorescent features or microparticles with a label.

Another advantageous embodiment is that the watermark can only be recognized by means of a technical device.

A further advantageous embodiment is that at least one photo of a user and / or at least one coding and / or at least one letter and / or at least one number and / or at least one symbol is / will be used. For example, a data matrix or a bar code or a QR code can be used as coding. In principle, any other suitable code may alternatively be used.

Another advantageous embodiment is that the watermark is stored in electronic form in a memory of the data carrier. As memory, there is e.g. a chip or a magnetic stripe of the data carrier.

Another advantageous embodiment is that the watermark is printed in a recess of the data carrier.

Another advantageous embodiment is that the watermark is printed separately and is subsequently introduced into a recess of the data carrier.

Another advantageous embodiment is that the watermark and the data carrier are printed together by means of the three-dimensional printing process.

Furthermore, the object is achieved by a portable data carrier, which is produced according to the above method. As portable data carriers according to the invention come e.g. a chip card, an ID card with a chip, a credit card or a SIM card in question.

• Figur 1 zeigt eine Seitenansicht eines Querschnitts durch eine Struktur eines erfindungsgemäßen Wasserzeichens.
• Figur 2 zeigt die Seitenansicht des Querschnitts durch die Struktur des erfindungsgemäßen Wasserzeichens, über die eine Schicht aufgetragen wurde, um eine ebene Oberfläche zu erhalten.
• Figur 3 zeigt ein Ausführungsbeispiel eines tragbaren Datenträgers mit zwei erfindungsgemäßen Wasserzeichen.

In the following the invention will be described in detail with reference to the attached figures.

• FIG. 1 shows a side view of a cross section through a structure of a watermark according to the invention.
• FIG. 2 shows the side view of the cross section through the structure of the inventive watermark, over which a layer has been applied to obtain a flat surface.
• FIG. 3 shows an embodiment of a portable data carrier with two watermarks according to the invention.

Before discussing the figures, it is intended to briefly discuss the essential features of the invention.

The invention discloses a method for producing a watermark 2, 8, 10 as a security feature for a portable data carrier 6. The method is characterized in that the watermark 2, 8, 10 is printed by means of a three-dimensional printing method in the form of a spatial structure. For this purpose, a brightness value is determined for at least one point of an image in accordance with an adjustable local resolution. Preferably, the respective brightness value is determined for all points of the image. Depending on the application, a suitable resolution can be selected for an image. The higher the resolution, the more details you can see. Then, for at least one brightness value at the location of the associated point of the image, a layer thickness of the watermark 2, 8, 10 to be printed is determined. Preferably, the layer thickness of the watermark 2, 8, 10 to be printed is determined for each brightness value.

The watermark 2, 8,10 is printed by means of an at least partially opaque material, wherein the light transmittance of the material is set such that when the layer thickness is modulated on the order of the thickness of the target substrate, the target substrate corresponding to the watermark to be produced, a very good contrast of the watermark when viewed in transmitted light.

At least one security feature is introduced into the material for printing the watermark 2, 8, 10. As a security feature, any suitable security feature can be used. For example, security features known from banknote printing can be used, e.g. fluorescent elements.

To create a flat surface, at least one layer 4 is applied to the printed watermark 2, 8, 10. For the at least one layer 4 to produce a planar surface, an at least partially translucent material is used. Preferably, a completely translucent material is used. For example, for the layer 4 to produce a flat surface, a clear coat is used. Advantageously, at least one pigment is introduced into the layer 4 to produce a planar surface to prevent scanning of the structure of the watermark 2, 8, 10.

The watermark 2, 8, 10 can only be recognized in one embodiment by means of a technical device. By way of example, a technical device may be a sensor or a camera, which may be e.g. capture only light of a certain wavelength. Alternatively, the watermark 2, 8, 10 can also be recognized with naked eyes.

For example, at least one photo of a user and / or at least one coding and / or at least one letter and / or at least one image can be used as image a number and / or at least one symbol are used. For example, a data matrix code or a barcode or a QR code may be considered as coding.

The watermark 2, 8, 10 is advantageously stored in electronic form in a memory of the data carrier 6. As memory, e.g. a chip or a magnetic stripe of the data carrier 6 serve. Thus, the disk 6 can be protected against illegal copying. A reader may store the data in memory, e.g. Chip or magnetic stripe, with the recorded on the outside of the disk 6 data watermark 2, 8,10 compare and check whether it is the disk 6 is a forgery. In addition, an optional feature introduced into the watermark material can be tested by detecting its physical properties by means of a sensor.

In the production, the watermark 2, 8,10 either alone or it can be printed directly into a recess of the data carrier 6. Alternatively, the watermarks 2, 8, 10 and the data carrier 6 can also be printed together by means of the three-dimensional printing method, so that a uniform body is produced.

FIG. 1 shows by way of example a side view of a structure of a watermark according to the invention 2. The watermark 2 can be prepared for example on a round or square or oval basic shape. For example, in a round basic shape, the watermark is circular when viewed from above. Clearly visible in FIG. 2 the elevations and depressions of the watermark 2, which determine the visual impression in a viewer. In the material of the watermark 2, a security feature, such as a fluorescent element, as it is used in the banknote area or in the range of ID smart card or passports are introduced.

FIG. 2 shows the side view of a structure of a watermark 2 according to the invention, over which a layer 4 has been applied to obtain a flat surface. An application of the layer 4 lends itself, for example, when the watermark 2 is installed in a data carrier body. For attaching the watermark 2 in a data carrier body, the watermark 2 or the layer 4 may be formed so that they have a fastening mechanism to produce a mechanical connection to the disk body. For the layer 4, for example, a clearcoat can be used, which cures, for example, thermally or by means of UV light after application to the watermark 2. Furthermore, pigments 4 can be present in the layer 4, which prevent scanning of the structure of the watermark 2, for example by means of a laser beam.

FIG. 3 shows an embodiment of a portable data carrier 6 with two watermarks 8 and 10 according to the invention. The two watermarks 8 and 10 can be made separately from the data carrier 6 and used after their manufacture in the data carrier 6, for example in a recess of the data carrier 6. The watermarks 8 and / or 10 are eg using an adhesive or a thermal joining method or a mechanical device, such as a clip mechanism on an outside of the watermark 8 and / or 10, permanently connected to the disk 6. In addition, it is possible to permanently insert the watermarks 8 and / or 10 into the data carrier 6 in its recess and a layer 4 to produce a flat surface on the watermark 6, 8, wherein the layer 4 in FIG FIG. 3 is not shown, subsequently introduce into the recess, for example by metering or spraying. For the layer 4, for example, a clearcoat can be used, which cures, for example, thermally or by means of UV light after application to the watermark 6, 8. In addition, the material of the layer 4 can undergo a chemical / mechanical connection to the data carrier 6. The layer 4 may terminate flush with the disk surface or may be slightly above or below the disk surface. In addition, the formed surface of the layer 4 may form a lens shape. Advantageously, a rear side of the recess of the data carrier 6 is translucent and / or has a light source so that the watermark 8 and / or 10 can be made visible. In the case of a light source in the disk 6, the back can be opaque. Alternatively, the data carrier 6 and the watermarks 8 and / or 10 can be produced together by means of the three-dimensional printing process. The watermark 8 is, for example, a portrait photo of a user of the data carrier 6, which is a credit card or ID card, for example. The watermark 10 is, for example, a code, eg a barcode, data matrix code or a QR code. The watermarks 8 and / or 10 can be detected and evaluated in transmitted light by a camera, for example. Alternatively, for example, the code of the watermark 10 may be invisible to the human eye and only by means of a suitable sensor, eg at a certain wavelength, to be read out.

LIST OF REFERENCE NUMBERS

2

Structure of a watermark according to the invention

4

Layer to create a flat surface on the watermark

6

portable data carrier with two watermarks 6 and 8 according to the invention

8th

Watermarks in the form of an image, e.g. a portrait photo of the user

10

Watermarks in the form of a code

Claims (10)

1. A method for producing a watermark (2, 8, 10) as a security feature for a portable data carrier (6),
   wherein the watermark (2, 8, 10) is printed in the form of a spatial structure by means of a three-dimensional printing process,
   characterized in that
   a brightness value is determined for at least one point of an image according to an adjustable spatial resolution,
   wherein a layer thickness to be printed of the watermark (2, 8, 10) is determined for at least one brightness value at the location of the associated point of the image,
   wherein the watermark (2, 8, 10) is printed by means of an at least partially light-impermeable material,
   wherein a light permeability of the material is adjusted such that upon a modulation of the layer thickness in the dimension of the thickness of a target substrate, wherein the target substrate corresponds to the watermark to be manufactured, a contrast of the watermark occurs upon viewing in transmitted light.
2. The method according to claim 1, characterized in that in the material for printing the watermark (2, 8, 10) at least one security feature is incorporated.
3. The method according to claim 1 or 2, characterized in that to the printed watermark (2, 8, 10) at least one layer (4) is applied to produce a flat surface.
4. The method according to claim 3, characterized in that an at least partially light-permeable material is employed for the at least one layer (4) to produce a flat surface.
5. The method according to claim 4, characterized in that a clear lacquer is employed for the layer (4) to produce a flat surface.
6. The method according to any of the claims 3 to 5, characterized in that in the layer (4) to produce a flat surface, at least one pigment is incorporated in order to prevent a scanning of the structure of the watermark (2, 8, 10).
7. The method according to any of the claims 1 to 6, characterized in that at least one photograph of a user and/or at least one coding and/or at least one letter and/or at least one number and/or at least one symbol is/are employed as image.
8. The method according to any of the claims 1 to 7, characterized in that the watermark (2, 8, 10) is stored in electronic form in a memory of the data carrier (6).
9. The method according to any of the claims 1 to 8, characterized in that the watermark (2, 8, 10) is printed in a recess of the data carrier (6).
10. The method according to any of the claims 1 to 9, characterized in that the watermark (2, 8, 10) and the data carrier (6) are printed together by means of the three-dimensional printing method.

Images