GB2076337A

GB2076337A - Identification cards

Info

Publication number: GB2076337A
Application number: GB8114739A
Authority: GB
Original assignee: GAO Gesellschaft fuer Automation und Organisation mbH
Current assignee: GAO Gesellschaft fuer Automation und Organisation mbH
Priority date: 1980-05-14
Filing date: 1981-05-14
Publication date: 1981-12-02
Also published as: FR2482525A2; DE3018485C2; FR2482525B2; DE3018485A1; CH652355A5; NL8102242A; GB2076337B

Abstract

An identification card is constructed of several film layers (22), provided with 8 monochrome or polychrome printed image (21, 23, 24). The printed image may consist of partially overlapping printed layers placed over each other and distributed over the surfaces of the film layers. Alternatively a layer may be monochromatically coated and printed to give an image. The card may exhibit shadow effects viewed in incident light which are reversed in transmitted light. A certain spatial effect and definite half-tone grading of the printed pattern can be achieved by the number and arrangement of the various layers. The printings may be on at least two different layer surfaces, i.e. on the two sides of one layer or on two different layers. In place of printings some layers can be coloured and perforated. <IMAGE>

Description

SPECIFICATION Identification cards This invention relates to identification cards with hallmarks adapted to be inspected by transmitted and incident light. Identification cards consist basically of a sheet-like substrate with, if desired, one or more layers laminated thereto. It is desirable, for security reasons, to provide such cards with hallmarks, the forging of which is difficult.

It is already known, in particular from the technical field involved of security printing, to provide securities with hallmarks, e.g. watermarks, in order to protect them from being forged and counterfeited. Watermarks are formed during the sheet formation process of the paper, i.e. when the sheet is formed either during the production of hand-made paper or in the cylinder machine. The watermarks are formed by providing the screen with a relieftype model in the hallmark area so that due to the existing raised and recessed features the thickness of the sheet at the corresponding locations is in some cases greater and in some cases less than the average basic weight. The result is an image which in transmitted light appears to have lighter and darker shadows, thus giving it a plastic effect. If viewed with incident light, this light/dark effect is reversed.Arbitrary half-tones can be achieved depending on the fiber concentration and sheet thickness in the watermark area.

The watermark is extraordinarily significant as a hallmark for securities by virtue of the fact that it is easy to inspect on the one hand and, on the other hand, because a high technical expenditure is required to produce a watermark. Frequently, in the case of papers for the production of bank notes, cheques, stock certificates and the like, the entire surface is covered with watermark patterns.

It is also known that many methods exist by which such watermark-like effects can be achieved, but which have only some of the properties of a watermark produced during sheet formation. Hence, compared to such watermarks, they are very inferior and relatively easy to differentiate from the true, integral watermarks.

In the field concerned with the production of products which are to be protected from forgery or counterfeiting, plastics have very recently come into use to an ever increasing extent. Identification cards are already known, for instance, which consist either completely of plastic or in which a paper inlay is laminated between two or more plastics foils.

When a paper inlay is employed, this bears the hallmarks such as a true watermark. In the case of so-called solid plastic laminates, i.e.

identification cards consisting of a plurality of laminated plastics foils, the use of watermarks is by nature impossible. Hence, one had to be content using other, different features such as a surface imprint, surface relief or magnetic inclusions, for instance.

In spite of an increase in the general production expenditure of the identification cards by including such features thus also enhancing the reliability against forgery-it was on the one hand still relatively easy to imitate such features and, on the other hand, it is normally impossible to inspect them by visual means. Thus, there has hitherto been no known process suitable for practical use nor any known technique for producing features in solid plastic laminates which necessitate a certain technical expenditure and whose optical properties permit visual authenticity inspection in transmitted and incident light.

According to a first feature of the present invention there is provided an identification card with hallmarks adapted to be inspected by transmitted and incident light, the identification card consisting of a sheet-like substrate, and optionally one or more layers laminated thereupon, wherein the substrate is monochromatic or monochromatically printed, and is additionally printed over a large area and in part with at least partially overlapping, two-dimensional areas.

The creation of such hallmarks necessitates a certain technical expenditure and can be applied to plastics substrates as well as to other substrate materials. The substrate is preferably a transparent plastic foil or even a plastic foil which has already been homogeneously dyed.

Owing to the color coating which overlaps only in part, arbitrarily graduated optical effects are possible in which, in spite of a homogeneous appearance, the areas which are brightest when viewed by transmitted light are brighter than the general surrounding areas and the darkest areas appear darker than the surrounding hallmark areas.

In particular, when employing the inventive markings outside of multilayered laminates, a final homogeneous color layer is preferably provided which covers the entire printed layer structure. Due to the homogeneous uppermost color layer, the underlying hallmark area becomes almost invisible when viewed by incident light. This effect can be varied as desired by varying the thickness or color density of the outermost printed coating.

In accordance with an advantageous embodiment of the invention, a large area of the substrate, which can be a transparent plastics foil, for instance, is initially printed thinly and subsequently overprinted a second time, those portions of the surface which are to appear lighter in transmitted light compared to the surrounding area being omitted. Then another color coating is then applied over the first and second layers in those areas in which dark effects are to be achieved in transmitted light.

Three different gray halftone values can be produced in this way with a superimposed arrangement of three layers which overlap only in part. An almost arbitrary further graduation of the gray halftone values can be achieved by additional color coatings which are superimposed on one another in such a way as to overlap in whole or in part.

Thus, a light/shadow effect is produced which has an aesthetic appearance in incident light and which reverses when reviewed by transmitted light. The artistic design is of course unlimited and any designs are possible.

The protection against forgery is enhanced if part of the color coatings located between the uppermost and lowermost layers is colored. Images of contrasting color can thus be produced in transmitted light which appear to be almost monochromatic when viewed in incident light. If all color coatings are chosen to be white, however, the sole effect obtained will be a hallmark with modulated pure gray graduations.

In order to produce halftones or gray tones or even graduated contrasting colors, the color coatings vary in thickness. The same effect can be achieved by selectively varying the number of layers which are printed one above the other or by accordingly adjusting the body of the colorant used in the printed coating.

The hallmarks can be produced in principle by all common printing methods such as offset printing, letter-press printing or the like.

Preferably, however, the colourant is printed by the silk screen process. In this process, an increase in the layer thickness can be attained by using a correspondingly larger mesh size of the silk screen mesh. The mesh also imparts to the colour coating a certain structure which constitutes an auxiliary. artisitic element.

According to a further development of the invention, one or, if desired, more plastics foils are laminated onto the substrate after this has been printed. In this way, for example, solid plastics identification cards can be manufactured which have hallmarks which can be used visually to inspect the authenticity of the identification card.

The body of the printing ink or colours can be consciously regulated by mixing the printing ink or colours with substances persons skilled in the art term transparent pastes.

This procedure permits halftones and colour graduations to be obtained without having at the same time to vary the layer thickness accordingly. Since in silk screening it is substantially impossible to vary the layer thickness without varying the mesh size, this renders silk screening less expensive for industrial production. The forger, however, cannot gain any advantage from this simplification due to the different mixing ratios of the printing inks required in this case.

In particular, when using printing inks whose body has been reduced greatly as well as in the processing of different layer thicknesses, an auxiliary artisitic effect can be achieved, since the layers with a high transparent concentration produce an especially plastic effect.

Moreover, in addition to the already existing effects in transmitted and incident light, automatically inspectable hallmarks can be simul--taneously provided in the hallmark area by using special printing inks with special physical properties such as fluorescence, specific spectral absorption or the like, for example.

Such automatically inspectable hallmarks will provide information about the authenticity of the respective document when it is suitably scanned, even in automatic inspection devices. The problem of integrating inspection hallmarks into solid plastics laminates in the form of authenticity hallmarks which can be inspected in transmitted and incident light, thereby rendering these solid plastic laminates suitable for examination both visually and automatically, can also be solved, however, in another way which still gives an identification card having features that can be tested in incident and transmitted light, whose manufacture requires a certain technical effort and which can consist of plastic layers.However, it is not necessary to arrange the printed areas on only one layer surface in the case of multilayer identification cards in order to solve the problem of making such identification cards as desired.

According therefore to a second feature of the present invention there is provided an identification card with authenticity features which are testable in incident and transmitted light consisting of at least two layers laminated together, and at least two monochrome printed images which at least partly overlap printed on the layers, the images being printed on at least two different ones of the at least four surfaces of the layers.

In cards according to this embodiment of the present invention the distribution of the various printed areas can be on the front side as well as on the reverse side of the various layers. This enables cards to be produced using different printing inks which may need' to be handled by different printing techniques, because of the separate printing on the various layers, so even inks not compatible with each other can be used. Furthermore, an additional spatial effect which extends the scope of variation possibilities is obtained due to the possibility of placing various elements of the printed pattern on different levels in the identification card. As it may well be the case that each layer is only printed once, printing can be carried out economically without deformation of the material of the layers. When several printed layers are applied to a carrier, as in the cards described above, there may be strains which cause wavy deformation during the drying process and complicate the further handling of the carrier in the subsequent lamination process. If one or more layers are printed on the front and reverse side simultaneously, this can be carried out without intermediate drying periods and if necessary also on simultaneous printing machines.

In place of printing to achieve the effects noted, perforation of homogeneously coloured sheets or areas can be used. Thus, according to a yet further feature of the invention there is provided an identification card with hallmarks adapted to be inspected by transmitted and incident light, the identification card consisting of a sheet-like substrate, optionally with one or more layers laminated thereupon, wherein a large area of the substrate and/or of one or more layers laminated thereto is printed thinly or otherwise coloured homogeneously, and areas are removed from the substrate and/or layer(s) over portions which are to appear lighter in transmitted light compared to the surrounding area.

Embodiments of the invention are described in the following by way of example with reference to the accompanying drawings in which Figure 1A shows an embodiment of an identification card according to the invention and embodying a hallmark consisting of three layers, Figure 1B is a schematic cross section through the identification card of Fig. 1A, Figure 2A shows another embodiment of an identification card according to the invention and incorporating a hallmark consisting of four layers, Figure 2B is a schematic cross section through the identification card of Fig. 2A, and Figures 3 to 7 are schematic cross sections through further cards according to the present invention.

Figs. 1 B, 2B and 3 to 7 show the layers separated for clarity. In the actual card they are, of course, adjacent.

The solid plastics identification card shown in Figs. 1A and 1 B has a transparent plastic foil T as the substrate and is printed with a homogenous layer 4. Two other printed layers 5 and 6 are located above the homogeneous printed layer 4. The layer 5 extends over the entire substrate T, save for a cut-out portion shaped like the figure "7". The layer 6, which is preferably designed to be somewhat thicker or to have more body, has the shape of the figure "7" and is positioned slightly offset with respect to the cut-out portion of layer 5 such that portions of layer 6 project into the cut-out portion of layer 5. Three surface areas 1, 2 and 3 can thus be differentiated due to the printed layers which are positioned above one another in this matter.

Two thin white colour coatings are positioned above one another in surface area 1. In surface area 2, the substrate T is covered by only one colour layer, while in surface area 3 substantially three colour layers are superimposed. When viewed in transmitted light, therefore, area 3 appears to be dark due to the absorption effect of the three layers, area 2 light and area 1 semi-dark. if white colours are used exclusively, this corresponds to a white/medium gray/dark gray graduation.

When viewed in incident light, this light/ dark effect is reversed, area 3 appearing light, area 2 dark and area 1 semi-dark. If white is used exclusively, the corresponding gray graduations will result.

During production, the layers are printed on the substrate in their proper sequence and are thereafter laminated or covered with a cover foil (not shown).

In the embodiment according to Figs. 2A and 2B, a thin white colour layer 4 is initially applied to a transparent substrate foil T as well. Thereafter, an oval print 7 with a red colour is applied which, however, only partly covers the surface of the card. In this colour layer, the contours of a specific figure, again the figure "7" in the illustrated embodiment, are cut out. Another thin white colour layer 8 is then printed over the entire surface and on top of the red colour layer and, finally, a colour layer 9 is applied in thick, white colour (ink) in the form of the contour of the specific figure, i.e. the figure "7" in this case. The result produced is surface areas 10 to 1 3 which show the following brightness values when examined with transmitted light.Area 11 appears red, area 1 2 light or white in the red field and area 1 3 dark or gray. When viewed with incident light, area 1 3 appears white and areas 10, 11, 1 2 exhibit gray graduations ranging from light gray to dark gray. No noticeable red colouring of the area 11 is noticed in incident light due to the body of the colour layer 8. It is self-evident that a correspondingly dyed foil or even a paper layer can be employed instead of the substrate and the first continuous white print.

By using special silk screening inks with special physical properties such as fluorescence, specific spectral absorption or the like, for example, in the production of one or more of the color layers, automatically inspectable hallmarks can be integrated into the hallmark area or into the surrounding area in addition to the already existing incident and transmitted light effects. When suitably scanned, these automatically inspectable hallmarks provide information concerning the authenticity of the information carrier even in automatic inspection devices.

For instance, it the color layer 4 shown in Fig. 1 contains fluorescent additives, areas 2 will be able to be recognized when suitable excited in an automatic inspection device due to their characteristic fluorescence. Since the remaining areas of the layer 4 are covered by color layers 1 and 3, no fluorescence will be discovered in these concealed areas, at least not from the front side. If a transparent sub strate T is used, in which the optical access to layer 4 is not impeded by other prints or laminations, the same fluorescence will be able to be inspected on the entire rear surface in an inspection instrument.Irrespective of whether the optical pattern is used in multilayer laminates or in non-laminated monolayer information carriers, any attempts to manipulate the identification card will disrupt and damage the predetermined structure of the fluorescent or non-fluorescent areas in any case so that the layer structure will indicate such tampering either by additional fluorescing areas on the front side, caused by ruptures in layers 1 and/or 3, or by impairment of the homogeneous fluorescence on the rear side caused by damage to layer 4.

If a plurality of different fluorescent substances or other different material properties which can be identified by machine is employed, this can do as much to enhance the reliability against forgery or counterfeiting as the use of more complicated patterns and layers structures.

The illustrated examples can be varied and modified as desired as far as the layer thickness, number of layers, colours, inks, shape and organisation of the surface areas are concerned.

Fig. 3 shows a card structure in which the various printed areas 21 each appear on the front side of a layer 22. This type of arrangement of the printed areas leads to a spatial separation of the various printing layers, which results in an additional spatial effect when the printed patterns are appropriately designed and especially when thick layers 22 are used besides the half-tone impression as described above. The three-dimensional impression is heightened when the single layers in addition homogeneously at least slightly inked or coated.

This effect can be additionally varied and strengthened by the use of films of differing thickness and printing layers of differing opacity, as the case may be.

Fig. 4 shows a construction in which a printed area 23 is arranged on the reverse side of an upper layer 22, along with printed areas 21 on the front side of the other layers 22. The two printed areas 21 and 23 on the front and reverse sides of the adjacent layers cannot be- distinguished from layers printed directly over each other, when the card is laminated.

This type of arrangement is especially interesting in cases when it is not possible to print the various printing elements over each other due to the employment of different printing processes and/or different incompatible inks, but where it is desired to maintain the impression of a single even printed pattern.

Fig. 5 shows again the layering of the printed areas on coincident levels. In this arrangement, the middle layer is printed on the front as well as on the reverse side with printed patters 21 and 24, which can take place in one operation without intermediate drying periods, if necessary.

Fig. 6 shows a layer construction in which printed areas 21 and 25 are printed on the middle layer directly over each other as described with reference to Figs. 1 and 2. The other layers are distributed on other surfaces of the single layers, as in the above examples.

The lowest layer 22 has a printed pattern 21 congruent to the printed pattern 24 on the reverse side of the middle layer, which results in a reinforcement of this printed area when looked at in transmitted light, without any variation of the inks or the printing thickness being necessary.

All the examples up to now have been geared to printing layers over each other. It is clear that the same or similar effects can be achieved by using homogeneously coated or inked single layers from which the colourant has been removed in areas which are to be transparent. This can take place most simply and for simple cases of application by punching out the light areas, as shown in Fig. 7.

In order not to disturb the even application of the laminating compound by the areas of differing thickness, relatively thin single layers 27, compared to the entire thickness of the identification card, should, however, chiefly be used in this case, which layers may be supplemented as required by additional neutral layers with the necessarly thickness.

The examples stated above are only a small selection of the host of possibilities of variation. Of course, the single layers can be applied in the form of plastic films as well as paper layers, though due regard must be had to the steps necessary for laminating them together to give the final multi-layer construction of the card. Furthermore, the number of layers and printings for an identification card is not limited in any way. The combination of, single effects and single steps is also possible in any way one chooses. Thus the cover films can also be printed at the same time, whereby the carrier can also be constructed with one layer.

Claims

1. An identification card with authenticity features which are testable in incident and transmitted light consisting of at least two layers laminated together, and at least two monochrome printed images which at least partly overlap printed on the layers, the images being printed on at least two different ones of the at least four surfaces of the layers.

2. An identification card according to claim 1 and consisting of three or more layers.

3. An identification card according to claim 1 or 2 wherein the printed images are placed otherwise than on the two outer surfaces of the outside layers.

4. An identification card according to any one of claims 1 to 3 wherein printed images are provided on the front and reverse sides of at least one of the layers.

5. An identification card according to any one of claims 1 to 3 wherein the printed areas are provided on only the front sides of the two or more layers.

6. An identification card according to claim 2 wherein one or more layers are coated or inked over their entire surface and are punched out.

7. An identification card according to any one of claims 1 to 6 wherein the layers have differing thicknesses.

8. An identification card according to any one of the preceding claims and including one or more intermediate layers which are coated or transparent over their entire surface placed between the printed and/or punched layers.

9. An identification card substantially as hereinbefore described with reference to any one of the Figures of the accompanying drawings.

1 0. An identification card with hallmarks adapted to be inspected by transmitted and incident light, the identification card consisting of a sheet-like substrate, optionally with one or more layers laminated thereupon, wherein the substrate is monochromatic or monochromatically printed, and is additionally printed over a large area and in part with at least partially overlapping, two-dimensional areas, and wherein the printed areas are arranged on more than one e.g. several layer surfaces of the identification card or its base.

11. An identification card with hallmarks adapted to be inspected by transmitted and incident light, the identification card consisting of a sheet-like substrate, optionally with one or more layers laminated thereupon, wherein a large area of the substrate and/or of one or more layers laminated thereto is printed thinly or otherwise coloured homogeneously, and areas are removed from the substrate and/or layer(s) over portions which are to appear lighter in transmitted light compared to the surrounding area.