NZ612971B2 - Method for producing a multilayer data carrier and data carrier produced by said method - Google Patents

Abstract

Method for producing a multilayer data carrier for example an identity card, passport, or driver’s license, which is protected against unauthorised modifications. The data carrier has a first layer (8) of plastic that comprises an upper side on which an opaque layer (5') partially covering this upper side is arranged. A second layer (6) of plastic is arranged on the first layer (8) and is transparent at least in a subregion of the opaque layer (5'). The opaque layer (5') is partially removed using a laser until the opaque layer (5') has at least one recess. The opaque layer is arranged within a window of an opaque core sheet (7'). r side is arranged. A second layer (6) of plastic is arranged on the first layer (8) and is transparent at least in a subregion of the opaque layer (5'). The opaque layer (5') is partially removed using a laser until the opaque layer (5') has at least one recess. The opaque layer is arranged within a window of an opaque core sheet (7').

Description

TITLE Method for Producing a Multilayer Data Carrier and Data Carrier Produced by said Method TECHNICAL FIELD The invention relates to a method according to the preamble of claim 1.

In order to protect data carriers, for example identity cards, passports, driver's licenses, bank cards etc. having personalized data, security features are variously used. A very wide variety of security features for protecting the blank card without personalized data are known from the prior art. Often, however, it is the case that the forger does not forge a complete card but modifies or replaces the personalized data (photograph, date of birth, signature, name, etc.) on an e.g. stolen card. The tion of these personalized data is therefore very important. Techniques known from the prior art for protecting such data are, for e, the personalization of a second image in a lens structure, in such a way that the image is only visible at a particular observation angle. Another possibility for introducing a second image is to introduce a matrix image into the card by perforating the card. These tion methods are vely elaborate and require special devices during the card production (lens structure) or special machines for introducing the second image. The t ion provides a way in which the personalization can be protected in a straightforward way without additional machines.

PRIOR ART Any comment regarding prior art is not to be taken as an admission or acknowledgement that the prior art forms part of the common l knowledge in the art. 40 EP 1691 989 B1 discloses a data r which comprises a metal layer that is arranged between two translucent cover layers (light transmittance less than 10%). A “watermark” effect is intended to be created by ablation of the metal layer using a laser beam.

EP 2 109 014 A1 discloses a so-called overlay of laserable polycarbonate with a holographic layer on one side. The holographic layer can be metallized and partially ablated using a laser. discloses a security document comprising a metallized sheet, which is laminated surface-wide between transparent layers. A large part of the sheet is modified/printed in order to form the card background. A window of the sheet is left unmodified.

After manufacture of the card, an image which is visible from the front side and rear side of the card is introduced into this window by means of laser ablation.

EP 0 420 261 relates to a method for producing a series of data carriers sing holograms, in which the holograms are individualized by partial destruction or modification of the ction structures.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing a data carrier which is protected better against orized modifications. The data r is nevertheless intended to be produced economically.

It is an alternative object of the invention to at least provide the public with a useful choice.

Preferred aspects of the ion are set forth in claims 1 and 9 with red embodiments in the dependent claims.

The invention relates in particular to a multilayer 40 data carrier of thermoplastic (for example polycarbonate, PVC, . According to one refinement of the invention, a ably metallized thin layer is applied partially onto one of the layers. This - 3 — metallized layer may for example be vapor deposited, applied by hot ng or laminated together with a carrier layer (for example PET) between two layers of the data carrier. The metallized layer is advantageously thinner than 4 um, in the ideal case thinner than 1 um. If it is laminated er with a carrier layer, the carrier should be no thicker than 50 um, in the ideal case about 20 um or thinner. The metallized layer may contain holographic diffraction structures. The metallized layer consists, for example, of aluminum, although other metals may be envisioned, for example titanium. The techniques for applying the metal layer onto a thermoplastic sheet are known to the person skilled in the art. The thermoplastic sheet is advantageously r than 50 pm, in the ideal case 100 um or r.

The layer with the partially applied. metal layer is then laminated er with the further layers of the cards to form a card body. In this case, the layer with the applied metal is covered with at least one further transparent layer. The layer onto which the metal is applied may be either transparent or opaque.

During personalization of the card, that is to say when writing the cardholder’s data onto the card, the metal layer is then partially ablated, i.e. evaporated, using a laser. At the positions where the laser strikes the metal layer, the metal sheet evaporates and a recess is 3O formed in the metal. Text or matrix images can therefore be written into the metal sheet using the laser. For this process, it is possible to use the same type of laser as is ed for the data carrier alization known from the prior art (laser marking by means of blackening). It is, however, also possible to use a laser with a different wavelength. — 4 — 2012/000008 When the metal layer is evaporated, the sheet below the metal layer is visible h the gap left in the metal sheet. ing on whether this sheet is arent or opaque, the image formed in the metal layer is optimally visible in transparent view (in the case of a transparent sheet) or direct view (in the case of an opaque sheet). Owing to the reflection or of the metal layer, the image can be seen in direct view as “positive" (dark) or ive” (light) depending on the viewing angle.

According to a refinement of the invention, the sheet is printed in a color before application of the metal layer, so that the color is visible through the gaps in the metal layer after the ablation of the metal layer and provides a special effect.

According to a refinement of the invention, the metal layer is introduced or applied, respectively, onto or into a transparent window in the data carrier, so that the d image is visible in transparent view but the rest of the data carrier comprises an opaque core layer.

According to a refinement of the invention, a thin Opaque plastic layer having a special additive is used instead of a netal layer, this additive modifying the opaque c layer during the exposure in such a way that it becomes transparent or at least translucent.

The additive is, for example, a pigment which is destroyed during the exposure to a laser. Such pigments are known to the person skilled in the art. Instead of a pigmented plastic, it is possible to use a semicrystalline opaque plastic in which the macromolecules arranged in crystallites are converted into an amorphous and transparent structure by the heat input of the laser radiation.

The opaque plastic layer may, for example, be uced into the card structure as a co-extruded sheet or as a separate sheet by the known techniques.

Unless the t clearly requires otherwise, throughout the description and claims the terms “comprise”, “comprising” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense. That is, in the sense of “including, but not limited to”.

BRIEF DESCRIPTION OF THE DRAWINGS Exemplary embodiments of the invention will be explained in more detail below with the aid of the drawing, in which: Fig. 1 schematically shows a plan view of a data carrier according to the invention Fig. 2 shows a cross section through a data carrier according to the invention, Fig. 3 shows a cross section through a data r according to the invention according to a Fig. 4 shows a cross section through a data carrier according to r variant.

PTION OF PREFERRED EXEMPLARY EMBODIMENTS Figure 1 shows a data carrier 1, which according to Figure 2 comprises an opaque core sheet 7, a lower transparent cover sheet 8 and an upper transparent cover sheet 6. A metal layer is applied onto an upper side 14 of the core sheet 7, for example vapor deposited or applied by hot stamping. In what follows, a metal layer also refers to a metallized layer or a metallic layer. Such layers are known per se. They are relatively thin and have for example a thickness of 4 micrometers, preferably less than 1 micrometer. The metal sheet may also be formed as a am. The cover sheet 6, the core sheet 7 and the lower cover sheet 8 are bonded in a manner known per se by lamination. The 40 metal layer 5 then correspondingly lies between the core sheet 7 and the cover sheet 6. Using a laser apparatus, the metal layer is removed in such a way that, for example, the ablated second image 3 and the — 6 — ablated second text 4 are formed in Fig. 1. They are preferably formed by a recess in the metal layer 5. The opaque core sheet is visible through these recesses.

Before the application of the metal layer, the opaque core sheet may be printed in the region of the metal layer or below the latter. The second image 3 and the second. text 4 can then correspondingly’ be seen. in a color hue. Then, the second text 4 therefore appears blue or red, for example.

The data carrier according to Fig. 3 has a core sheet 7’, which comprises a transparent sheet 9 on which the metal layer 5’ is applied, for example vapor deposited.

The ablated regions are in this case visible from both sides, that is to say in Fig. 3 from above through the cover sheet 6 and from below through the cover sheet 8.

Fig. 4 shows a data carrier 1’ which comprises a core sheet 12 that has a transparent sheet 13, which comprises a first metal layer 10 and. a second Inetal layer ll. These metal layers 10 and ll may se be vapor deposited or applied by hot ng. These two metal sheets 10 and ll are at a distance from one another of, for example, at least 50 micrometers or preferably 100 or more micrometers. During the ablation using the laser, as indicated, the data carrier 1’ is placed obliquely at a ermined angle A. The ablation takes place in the two metal layers 10 and ll.

If, owing to the laser intensity, it is not possible to 3O ablate the two metal layers 10 and ll from the same side of the card, two matching laser processes may also be envisioned on the rear side and the front side of the data carrier 1’. In this case, the closer—lying metal layer 10 or 11 is respectively sed. By identical placement of the data carrier 1’ before the laser processing, the lasered image is visible in transparent view only at the ponding viewing angle. It is also conceivable to laser two different — 7 — images with different angles from one another, and thus obtain a tilt effect between the two images, or the two metal layers 10 and 11, during ation at different angles. The core layer 12 may, as can be seen, be fastened and in particular laminated between two layers, or cover sheets.

W0 2012/097463 - 8 — LIST OF REFERENCES data carrier metal sheet ablated second image ablated second text metal layer cover sheet U1:-I>0Jl\)|-‘ opaque core sheet transparent cover sheet w transparent sheet PAPA o first metal sheet F4 second metal sheet H N core sheet F4 o) transparent sheet H a upper side PATENT

Claims (19)

1. A method for producing a multilayer data carrier, which has a first layer that comprises an upper side on 5 which an opaque layer partially covering this upper side is arranged, and having a second layer which is arranged on the first layer and is transparent at least in a subregion of the opaque layer, wherein the opaque layer is partially removed using a laser until the 10 opaque layer has at least one recess and wherein the opaque layer is a metal layer, wherein the first layer and the second layer are of c and in that said opaque layer which is treated by said laser is arranged in a window of an ise at least regionally opaque 15 core layer.

2. The method as claimed in claim 1, wherein the opaque layer is laminated between the first and second plastic layers.

3. The method ing to claim 1 or 2, wherein the opaque layer providing said window is the core layer between the first layer and the second layer. 25

4. The method as claimed in any one of claims 1 to 3, wherein the data carrier is produced with at least two metal layers arranged parallel above one r, and these at least two metal layers are provided with recesses.

5. The method as claimed in claim 4, wherein the at least two metal layers are exposed perpendicularly with respect to their plane or at an inclination with t to their planes, so that the recesses extend 35 vertically or at an inclination with respect to said planes.

6. The method as claimed in claim 4 or 5, wherein at least two metal layers are arranged at a distance from one another.

7. The method as claimed in any one of claims 4 to 6, wherein at least two metal layers are arranged in a window of an opaque layer that is a core layer. 10

8. The method as claimed in claim 7, wherein the core sheet is laminated between two transparent sheets.

9. A data carrier ed according to one of claims 1 to 8.

10. The data carrier as claimed in claim 9, n it is an identity card, a page of a passport, a credit card or the like. 20

11. The data carrier as claimed in claim 9 or 10, wherein the opaque layer is a metal layer which is vapor deposited onto a sheet, applied by hot ng or laminated together with a carrier layer. 25

12. The data carrier as claimed in any one of claims 9 to 11, wherein the metal layer is thinner than 4 micrometers.

13. The data carrier as d in any one of claims 9 30 to 12, wherein the metal layer is thinner than 1 micrometer.

14. The data carrier as claimed in any one of claims 9 to 13, when dependent on claim 4, wherein in the case 35 of the at least two metal layers, they are at a ce from one another of at least 50 micrometers.

15. The data carrier as claimed in claim 14, wherein in the case of the at least two metal layers, they are - 11 – at a distance from one another of at least 100 micrometers.

16. The data carrier as d in any one of claims 9 5 to 15, wherein the regions exposed to the laser are visible from both sides of the data carrier.

17. The data carrier as d in claim 9, wherein owing to the reflection or of the metal layer, an 10 image when viewed can be seen as positive or negative depending on the viewing angle.

18. A method for producing a multilayer data carrier, substantially as herein described with reference to any 15 one of the embodiments shown in the accompanying drawings.

19. A data carrier, substantially as herein described with reference to any one of the embodiments shown in 20 the accompanying drawings.