EP0537484B1 - Recording media with coloured image, in particular credit or identity card - Google Patents

Abstract

The invention relates to a recording medium which is provided with pictorial information in a forgery-proof and high-resolution form, and to a process for its production. The pictorial information is broken down into a light/dark portion and a coloured portion. The light/dark portion, which determines the visual impression, is introduced into the recording medium in a high-resolution form. The coloured pictorial information is superimposed congruently on this portion, so that an integral overall impression is produced. In order to guarantee security against forgery, one of the portions of the pictorial information is introduced into the card structure in a substantially forgery-proof manner. <IMAGE>

Description

The invention relates to a record carrier colored image information, especially value or ID card and a method for producing a such record carrier.

At the current state of reproductive technology, that is Color representation of picture motifs is common and becomes general expected. Advertising also works preferentially color contrasts. Also record carriers like bank cards, Phonecards, credit cards etc. can do not withdraw from this train of time, d. H. you will be preferably provided with colored motifs, in particular if in addition to their actual function as Serve advertising media.

For the transfer of color images to such recording media a number of possibilities are known. In addition to the traditional photographic processes lately also so-called transfer procedures proven, in which the dyes of thin color carriers by thermal diffusion or thermal sublimation on the or are transferred into the image-bearing surface. Colored Images can also be made using the ink jet technique or through Thermal printers are generated to just a few ways to call.

The common disadvantage of all of these methods is however, that the color images applied under the Counterfeit security are insufficient, since they are only on the surface of a substrate or stick less firmly. This thin, superficial Layer that contains the dyes can be deliberate or removed or changed unintentionally. in the Case of ID cards, for example, two years or have more validity, there is a risk of mechanical wear or fading due to environmental influences.

A justifiable from a safety point of view Form the possibility to transfer a color image migrating colors, as described in DE-PS 27 50 984 are known. The migration of colors on it is based on the fact that special colors first on a plastic layer printed and then by heating be activated in the volume of the plastic carrier to wander in has compared to the other color pictures generating process the advantage that the colors over the surface area in the volume of the plastic layer are present and therefore not easy to remove are. The depth of penetration can be controlled as desired, by giving the plastic a reactive cross-linkable Component is added, which at the desired depth of penetration, e.g. B. activated by irradiation with UV light can be. Through the onset of networking further migration of the dye stopped.

The procedure requires special coordination of the colors used on the one hand and the plastic carrier used on the other hand. With a correspondingly high penetration depth of colors that come from safety Is desirable for reasons, the resolution or Sharpness of the image information.

From the point of view of counterfeit security at the same time high image resolution have become so-called Laser beam recorders have proven their worth in those to be transferred Information using a focused laser beam burned into the material of the record carrier will. From DE-PS 29 07 004 is an ID card with a paper card insert and a transparent one Cover film known for certain information after lamination of the cover film using a laser beam written directly into the card insert or be branded.

From DE-PS 31 51 407 is a multi-layer ID card with a specially designed transparent Cover film known. The cover sheet is despite its transparency able in the visible range of the spectrum absorb the energy of the laser beam so that Information written directly on the cover film can be.

The advantage of using a laser beam recorder lies primarily in the fact that the generated Markings are not superficial, but in the depth of the recording material. The Carrier material starts from the surface discolored to deeper layers. The discoloration takes place by local burning or by local soot, it is irreversible. At the same time, the Focal spot of the laser can be limited so that at precise control clear and finest details capturing portraits can be generated.

When using laser beam recorders and usual Card assemblies are the image information in general through a black and white contrast or corresponding semitones reproduced. The generation of security equivalent colored motifs is usually not possible.

A distinction must therefore be made in the prior art between information as black and white contrast in high resolution in a record carrier can be introduced and the largely are forgery-proof and, on the other hand, color images that applied by conventional methods, but either removed or changed with little effort can be or with sufficient counterfeit security provide a low image resolution.

The object of the invention is the further development of known ones Record carrier in that they with a colored image information can be provided, which is also fine Includes details, is practically irreversible and can hardly be faked. The record carrier but should despite this high level of security against counterfeiting be simple and inexpensive to manufacture.

According to the invention, this task is performed by the independent Claims resolved. Beneficial Further training is to the subclaims remove.

The key to the invention is the knowledge that to split the image information into two parts namely a light / dark part and a colored part Proportion of. One of these parts, preferably the light / dark part, is largely forgery-proof transparent film layer introduced. This way The generated partial image then becomes congruent with the respective one other portion, preferably the color compartment, the same Image information overlaid. This results in a complex one Overall impression resulting from the color value of the different superimposed image components and the backscattering force of the background. One removes now the reversible part of the image information remains still the part firmly anchored in the map structure, the makes identification possible without change.

In a preferred embodiment, the authenticity by means of those introduced by means of a laser permanent black and white display secured; the one printed over it or otherwise applied Color information provides the desired aesthetic appealing effect. The invention therefore enables colored image information on record carriers such as Use value or ID cards, the colored ones Pictures in their entirety cannot be faked, because part of the picture in irreversible form in volume of the material of the record carrier is present.

It proves to be particularly advantageous that with the Invention of existing technologies, each for itself considers the task of being counterfeit-proof and tamper-proof Producing a color image, cannot solve it, be combined in such a way that the advantages of each Technologies can be used without their disadvantages in Purchase must be made. For example, the Combine sharp black and white information with more or less blurry color information at all times possible without blurring the resulting color image appears. This aspect can even be seen in continuing education Invention can be used specifically by the color information of the image not only applied in techniques that result in fuzzy contours (e.g. migrating colors) but by adding the color information already in relatively coarse resolution, i.e. H. with reduced Data expenditure, are processed.

Fig. 1 - 3

Querschnitte durch Ausführungsbeispiele des erfindungsgemäßen Aufzeichnungsträgers und

Fig. 4

eine schematische Darstellung einer Vorrichtung zur Herstellung eines Aufzeichnungsträgers.

Some embodiments of the invention are described below with reference to the accompanying drawings, for example. Show in it

1 - 3

Cross sections through embodiments of the record carrier according to the invention and

Fig. 4

is a schematic representation of an apparatus for producing a recording medium.

The record carrier shown in Fig. 1 is concerned it is a multi-layer recording medium, consisting of a card insert 10, which is used as a light diffuser Background looks. The ticking 10 can optionally min a general print image and a Background pattern 12 may be printed. The background pattern can be added be designed so that it harmonizes with the applied image information. For securities It is particularly common to use guilloche patterns that are difficult to imitate Use background pattern. There is one on the ticking arranged transparent film 14, for example a Rigid PVC film, as described in DE-PS 31 51 407 is described. This slide is with additives doped so that they are in the wavelength range of the laser beam recorder absorbs energy in a defined form, but largely in the visible wavelength range transparent, d. H. is transparent.

A laser beam recorder is used to insert into the transparent film a certain information in the form of more or less blackened areas. The blackened areas, designated 16 in the figure, modulate the intensity of the light scattering background of the inlet 10 reflected portion of the incident Light. The blacker the areas are, the lower the intensity of the viewer reflected reflected light.

On the transparent film 14, an ink-absorbing Layer 18 may be arranged after completion of the Card has the appropriate dyes that the Display the color portion of the image information. Instead of the ink-receptive layer 18 can also contain the color information be printed directly on the film 14. Prefers are modern transfer techniques for the transfer of the Color image used. With such techniques the dyes from a thin fern base with heating transferred to the record carrier. The transmission mechanism is either a diffusion step or a sublimation step, depending on the type of used Color carriers or dyes. The attachment of a special ink-absorbing layer 18 is then recommended when migrating colors are used.

An example of a transfer procedure is in the European one Patent application 0 390 928 described. In the known technology is a thermal sublimation process used to transfer dyes from one ink carrier to one To transport record carriers. In the known case the heat required for sublimation an appropriately shaped stamp fed. It is however, it is also possible to use the required energy with a Feed laser beam.

For the viewer, this overlaps in the film layer existing black and white positive or gray tone image in the form of the blackening 16 with that printed on the film layer or applied color image 20 to an integral Overall impression. When removing the color image 20 or the color layer 18, the gray tone image 16 remains as before, a change in color image 20 would immediately visible to the viewer, because then the another light / dark contrast belonging to the picture motif would, or not fit to the changed image motif would.

Another embodiment of the record carrier according to the invention is shown in Fig. 2. The ticking 10, which are made of paper or plastic can, is done electrophotographically with the color components the image information 32. Appropriate Process for the electrophotographic introduction of image information in record carriers are e.g. B. from EP-PS 0 012 374 or EP-PS 0 024 344 known.

The ticking can of course also be used in this case be provided with a background pattern for reasons the clarity is not shown in the figure. Then over the colored fixed toner image a thin transparent cover sheet 36 arranged in the the light / dark portion of the image information 34 by means of a laser beam recorder is burned in.

3 shows a further variant of the invention Recorded medium shown. In contrast to that in Fig. 1 shown recording medium meets the colored Share of information here in addition to aesthetic needs also the requirements for security against counterfeiting. To counter the disadvantage of low resolution, in this case too, it is used for the visual impression determining light / dark information with a corresponding Procedure, but in more or less reversible form applied to the record carrier.

Here, the ticking 10, again with a background pattern can be printed using conventional Processes such as ink jet, screen printing or the like or also electrophotography with black and white information 48 provided and in the following step with a covered essentially transparent plastic film 44, those for capturing migrating colors suitable is. Congruent to this light / dark information 48 are the colored image parts 46 by means of migrating Colors introduced in the depth of the top layer. The Cover film can first with the colored image information be screen printed. Under the influence of heat the color migrates into the inside of the top layer so long, until crosslinking in the UV radiation Top layer is initiated, which is a further migration stops. This and similar procedures are from the beginning already mentioned DE-PS 27 50 984 known.

Alternatively, the color information can also be entered into the Top layer are introduced; only afterwards the light / dark information with conventional printing methods upset.

For all exemplary embodiments, the colored Information on the generation of special effects also "alienated" can be. For example, the colored image information even from one or two color value separations consist. Likewise, instead of the light / dark information a certain distinctive color value in black and white, i.e. can be displayed as a gray tone image.

In Fig. 4 is an apparatus for producing a recording medium shown schematically in FIG. 1. First, the image information is electronically broken down into a light / dark part and a colored part. Such is known from modern printing technology and familiar to the expert.

First, the record carrier or the transparent one Foil layer 14 with the light / dark portion of the "Information" described. This is done with a conventional one Laser beam recorder, which is only hinted at here is. A laser beam passes from a laser 24 via a laser beam Deflection device 26 and one not shown here Focusing optics on the surface of the film layer 14. The energy of the Laser beam is absorbed, causing the material thermally decomposed or discolored.

In a second process step, the so in the Foil layer generated gray tone image of the associated colored Image portion printed congruently. In the example shown one uses a transfer procedure for this. About the Supply rolls 28 is a thermal diffusion film in immediate vicinity of the film layer 14 brought. A beam expansion lens 28 is in the beam path swung in and causes the laser beam a surface 30 of the thermal diffusion band is heated, the is larger than the focus of the laser beam when enrolling of the gray tone image in the film layer 14. Due to the thermal radiation in the diffusion film The dyes diffuse energy into the recording medium or in one provided on the record carrier ink receptive layer 18.

The thermal diffusion film can be used at certain intervals have transparent windows for the laser radiation, so the position of the supply rolls throughout Recording process must not be changed. Because in the first step of the process such Through the window the light / dark portion in the film layer 14 registered. For the second step then becomes a heat sensitive area of the strip is transported into the effective range of the laser, so that the color information can be transmitted.

Due to the different grid size (resolution) between gray tone image and color image can be certain aesthetic effects can be achieved. Of course you can also work with the same resolution, for example then, if the colored part of the picture is not using a Transfer procedure applied, but using a conventional method is printed.

Regardless of whether the two pieces of information with the same "printing device" as that shown in Fig. 4 Laser arrangement or in completely separate process steps is always a coordination of the records necessary for the desired Congruence is achieved. According to the invention Congruence, for example with data records achieved, the common on the card edges have xy coordinates. Alternatively, of course you can Markings are also provided in the printed image of the card be detected by optical sensors and with their Help the assignment is accomplished. Such markings can, for example, limit the field into which the image is to be placed. Alike but it can also be any, as inconspicuous as possible integrated in the general printed image, conventional Be print marks.

The device described in Fig. 4 is only one Example; it has the particular advantage that both manufacturing steps, d. H. Inscription of the gray tone picture and applying the colored image information through which Using the same laser recorder can be. Would be a printing process for applying of the colored partial information, the Record carrier after the gray tone image has been introduced be transferred to an appropriate printing device. Knowing the principle of the invention, these are other embodiments but with the knowledge of Average specialist can be realized.

Claims (30)

1. A recording medium, in particular a pay card or the like, with picture information (16, 20, 32, 34, 46, 48) composed at least of one light/dark portion (16, 34, 48) and at least one color separation (20, 32, 46), characterized in that either the light/dark portion (16, 20, 32, 34, 46, 48) or the color separation (20, 32, 46) is incorporated irreversibly m the recording medium by means of a laser (24) and the other part of the picture information at least partly overlaps the part incorporated with the laser.
2. The recording medium of claim 1, characterized in that the recording medium has at least one transparent film layer (14, 36, 44) in which a portion (16, 34, 46) of the picture information is present in an irreversible form.
3. A recording medium, in particular a pay card or the like, with at least one transparent film layer and with picture information (16, 20, 32, 34, 46, 48) composed at least of one light/dark portion (16, 34, 48) and at least one color separation (20, 32, 46), characterized in that either the light/dark portion (16, 34, 48) or the color separation (20, 32, 46) is incorporated irreversibly in the transparent film layer and the other part of the picture information at least partly overlaps the irreversibly incorporated part.
4. The recording medium of claim 2 or 3, characterized in that the transparent film layer (14) is applied as a cover film on a carrier layer (10), as in a card inlay.
5. The recording medium of claim 4, characterized in that the carrier layer (10) has a background pattern (12) that harmonizes with the picture information.
6. The recording medium of at least one of claims 1 to 5, characterized in that the other portion (20) is disposed over the irreversible portion (16, 46).
7. The recording medium of claim 6, characterized in that the light/dark portion (16, 34) of the picture information is incorporated irreversibly in the film, and the color separation (20) and possibly further color separations are printed on the film (4).
8. The recording medium of claim 6, characterized in that the color separation (46) and possibly further color separations are incorporated in the film in irreversible form, and the light/dark portion and possibly further color separations are printed on the firm (14).
9. The recording medium of at least one of claims 6 to 8, characterized in that the other portion (20) of the picture information is present in a separate ink-receiving layer (18) disposed on the film layer (14).
10. The recording medium of at least one of claims 1 to 5, characterized in that the other portion (32, 48) is disposed under the irreversible portion (34, 46).
11. The recording medium of claim 10, characterized in that the light/dark portion (34) and possibly further color separations are incorporated in the film irreversibly, and the color separation (32) and possibly further color separations are provided on the carrier layer (10).
12. The recording medium of claim 10, characterized in that the color separation (46) and possibly further color separations of the picture information are incorporated in the film (44) irreversibly, and the light/dark portion of the picture information (48) and possibly further color separations are provided on the carrier layer (10).
13. The recording medium of at least one of claims 2 to 12, characterized in that the transparent film layer (14) is made of hard PVC.
14. The recording medium of at least one of claims 1 to 13, characterized in that the color separation and possibly further color separations of the picture information gray-tone picture have a lower spatial resolution than the light/dark portion.
15. The recording medium of any of claims 1 to 6 and 8 to 14, characterized in that the color separation (20, 32, 46) is incorporated irreversibly by means of migrating inks.
16. A method for producing a recording medium, in particular an identity card, with picture information composed at least of a black-and-white portion and a color portion, characterized by the following steps:

    breaking the picture information down into a black-and-white portion, on the one hand, and a color portion, on the other band, using electronic methods known in the art,

    incorporating the black-and-white portion of the picture information in a sensitized, transparent film layer by means of a controlled laser beam,

    overlaying the black-and-white portion of the picture information with the color portion of the same total information.
17. The method of claim 16, characterized in that the color portion of the picture information is disposed over the black-and-white portion and printed on as an ink layer.
18. The method of claim 16, characterized in that the color portion of the picture information is disposed over the black-and-white portion and transferred as an ink layer by the transfer method.
19. The method of claim 18, characterized in that a special ink-receiving layer is applied to the film layer for taking up the colorants transferred by the transfer method.
20. The method of claim 18 or 19, characterized in that the colorants are transferred by a thermosublimation method or thermodiffusion method.
21. The method of at least one of claims 18 to 20, characterized in that the thermal energy for the ink transfer is supplied by a laser beam.
22. The method of claim 21, characterized in that the incorporation of the black-and-white portion in the film layer and the ink transfer are performed with one and the same laser.
23. The method of claim 21 or 22, characterized in that the laser beam is focused less strongly for the ink transfer than for producing the black-and-white portion.
24. The method of claim 16, characterized in that the film is applied to a carrier layer, and the color portion is disposed on the carrier layer below the black-and-white portion.
25. The method of claim 24 characterized in that the color portion is applied by electrophotographic means.
26. A method for producing a multilayer recording medium, in particular an identity card or the like, with picture information composed at least of a black-and-white portion and a color portion, characterized by the following steps:

    breaking the picture information down into a black-and-white portion, on the one hand, and at least one color portion, on the other hand, using electronic methods known in the art,

    applying the black-and-white portion to an inner layer of the recording medium,

    covering the inner layer bearing the black-and-white portion with a substantially transparent film layer,

    overlaying the black-and-white portion with the color portion of the picture information by incorporating the color portion in the film layer by means of migrating inks.
27. The method of claim 26, characterized in that the black-and-white portion is printed on or produced by electrophotographic means.
28. A method for producing a recording medium, in particular an identity card or the like, with picture information composed at least of a black-and-white portion and a color portion, characterized by the following steps:

    breaking the picture information down into a black-and-white portion, on the one hand, and at least one color portion, on the other hand, using electronic methods known in the art,

    incorporating the black-and-white portion of the picture information in a substantially transparent firm layer of the recording medium by means of migrating inks,

    overlaying the color portion with the black-and-white information of the same picture information.
29. The method of claim 28, characterized in that the black-and-white information is printed on.
30. The method of at least one of claims 16 to 29, characterized in that the black-and-white portion is the light/dark portion or a color separation as a gray-tone picture of the picture information.

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