GB2478537A

GB2478537A - Security documents

Info

Publication number: GB2478537A
Application number: GB1003824A
Authority: GB
Inventors: James Peter Snelling; Fern Dowdell
Original assignee: De la Rue International Ltd
Current assignee: De la Rue International Ltd
Priority date: 2010-03-08
Filing date: 2010-03-08
Publication date: 2011-09-14
Anticipated expiration: 2030-03-08
Also published as: PL2545489T3; CN102834835A; EP2545489A1; AU2011225930B2; ZA201206506B; CA2791757A1; GB2478537B; MY160573A; CA2791757C; GB201003824D0; EP2545489B1; HUE028270T2; ES2568613T3; WO2011110799A1; CN102834835B; TW201202062A; US8950679B2; AU2011225930A1; TWI561405B; US20130062416A1

Abstract

Security documents comprise a security substrate 10, preferably of paper, having at least two sets of regions 11,12 having a machine detectable characteristic, in which only a first set of regions is applied to a first surface of the substrate, wherein the at least two sets of regions together form a machine readable code. The substrate may have a second set of regions applied to a second opposing surface. The regions may be applied to the surface or at least partially embedded in the substrate. The machine detectable characteristic may be magnetism, luminescence, or conductivity, and may be printed. The machine readable characteristic may be visible or invisible to the naked eye.

Description

IMPROVENTS IN SECURITY DOCUNTS

The invention relates to improvements in security documents.

Documents of value and means of identification, such as banknotes, passports, identification cards, certificates and the like, are vulnerable to copying or counterfeiting. The increasing availability of colour photocopiers, electronic scanning and other imaging systems, and the improving technical quality of colour photocopiers, has led to an increase in the counterfeiting of such documentation. There is, therefore, a need to continually improve the security features of such documentation to add additional security features or to enhance the perceptions and resistance of simulation to existing features.

Security features generally fall in two categories, overt and covert. Overt security features are ideally easily recognisable to the person in the street without the need for an additional device, whilst being difficult to counterfeit or simulate. Covert security features are generally not made public and are preferably only detectable with the aid of special devices, such as automatic cash and note handling machines. Modern banknotes contain a range of these features, with an even higher-level security feature reserved exclusively for the issuing authority.

Machine readable security features can be located in one or more regions of the banknote, either in the substrate, in the printing or as an applied feature. Some examples of such features include holograms, security threads, magnetic inks, fluorescent pigments, phosphorescent materials, thermochromic features and conductive metallic features.

Unfortunately, to overcome these security features, some counterfeiters have started to produce so-called composite banknotes. In such composite banknotes, part of a genuine banknote is cut out and replaced by a paper strip or the like enabling the cut out part to be used to produce a further, counterfeit banknote or bill. As cash deposit machines will return banknotes that cannot be validated, counterfeiters can use trial and error to determine the locations of machine readable features on notes.

A split note is a type of composite counterfeit note that involves splitting a note down the plane of the paper and creating a new note which comprises the front of the genuine note joined to the back of a counterfeit note. The presence of the half of the genuine note allows these notes to be accepted by a cash deposit machine which validates only one side of the note.

It is therefore an object of the present invention to provide an improved machine readable security feature which will overcome this problem.

According to the invention there is provided a security substrate having at least two sets of regions having a machine detectable characteristic, in which only a first set of regions is applied to a first surface of the substrate, wherein the at least two sets of regions together form a machine readable code.

A preferred embodiment of the present invention will now be described in detail, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a plan view of a banknote made from the substrate of the present invention; Figure 2 is a cross sectional side elevation of a substrate of the present invention; Figure 3 shows the magnetic signal detected by a detector from the substrate of Figure 2; Figures 4a and 4b illustrate the polarity of the magnetic signal for a material with high and low coercivities respectively; and Figures 5 to 7 illustrate alternate designs of banknotes made from the substrate of the present invention.

The security substrates of the present invention have a wide variety of applications, particularly as security documents such as banknotes, passports, bonds, certificates, vouchers or other documents of value.

Figure 1 illustrates a banknote made from the security substrate 10 of the present invention. The substrate selected will be dictated by the end application. In many cases the substrate will formed of paper (cellulose), polymer or a composite of the two. A suitable polymer substrate for banknotes is GuardianM supplied by Securency Pty Ltd. In this example the substrate 10 is preferably a fibrous substrate, such as paper. The substrate 10 comprises two sets 11,12 of machine readable regions. The sets 11, 12 of machine readable regions may be applied so that the first set of machine readable regions 11 are on one surface of the substrate 10 and the second set 12 of machine readable regions are on the opposing surface. Alternatively one set 11 of machine readable regions may be applied to one surface of the substrate 10 and the other set 12 of machine readable regions are carried on a security element at least partially embedded in the substrate 10. However it is important that they cannot be viewed simultaneously from either side of the substrate 10 and are seemingly unrelated.

The machine readable characteristic may be conductivity, fluorescence, luminescence, magnetic or another characteristic and the sets 11, 12 of machine readable regions may be visible (overt) or invisible (covert)to the naked eye. The machine readable characteristic is such that the sets 11, 12 of machine readable regions are preferably readable by a suitable detector from either side of the substrate 10. This minimises the need to modify existing cash handling machines.

If the sets 11, 12 of machine readable regions are visible they are selected to appear seemingly unrelated when the substrate 10 is examined visually. However when read by a detector the sets 11, 12 of machine readable regions together form a machine readable code. Thus if the substrate is split in the plane of the substrate 10, none of the split sections would have both sets 11,12. Thus if one part were used to create a composite counterfeit, the code would not be complete and the counterfeit document would be rejected as invalid.

To form the machine readable code there must be at least three machine readable regions, of which at least one must be in each of the first and second sets 11,12. Figure 2 illustrates first and second sets 11,12 of machine readable regions on opposing surfaces. The machine readable regions of the first and second sets 11,12 are positioned in a predeterminded relationship relative to each other, for example with specific distances between each region. Thus when the substrate 10 passes through the detector at a particular speed, the timing between the peaks will indicate the distance between the regions. The substrate 10 of the present invention will therefore produce a predetermined pattern of peaks as shown in Figure 3, whereas a composite counterfeit formed by cutting or dividing the substrate 10 into one or more sections and reassembling parts of it will not produce the correct pattern. The code is also preferably multidirectional, such that it can be read by machines that use either long or short edge feeding.

The code may be such that the denomination of a banknote may be determined from the code.

Where the regions are printed, the printing ink may be applied by any of the known printing techniques such as screen, flexography, lithography, intaglio, gravure, dye diffusion, laser, ink jet, letterpress and toner transfer.

The method used to print can affect the signal obtained from the code. For example intaglio printing lays down more ink than other printing methods so the signal would be stronger.

Litho printing would result in a more diffuse signal.

In one embodiment of the invention, the first and second sets 11,12 of machine readable regions are formed from a magnetic ink, such as iron oxide, or another iron, nickel or cobalt based material. Ferrites, such as barium ferrite, and alloys, such as A1NiCo or NdFeCo, would also be suitable. Hard or soft magnetic materials may also be used, or materials with high or low coercivity. Transparent magnetic inks such as those described in GB-A-2387812 and GB-A-2387813 are also suitable.

The code may be a block magnetic code. Block magnetic coding describes the arrangement of regions containing magnetic material separated by blank spaces. More advanced magnetic codes digitise the code. IMT is an example of spacial coding, and is described in EP-A-407550 and another type of coding is intensity coding.

The magnetic signal detected from a low coercivity material, such as nickel, can differ in polarity from an iron oxide type material depending on the geometry of the detector. If both nickel based and iron based magnetic inks are used at set positions, then a more complex code can be achieved. Figures 4a and 4b illustrate the polarity of the magnetic signal for a material with high and low coercivities respectively.

The magnetic material is typically detected by a magnetic detector but it also possible to detect the presence of a magnetic material using an x-ray detector as a magnetic material typically appears as a dark region in an x-ray image when present on a paper or polymer substrate.

Conductive polymer inks are available, such as PEDOT: PSS (Poly(3, 4-ethylenedioxythiophene) poly(styrenesulfonate), which can be applied by a printing process, to provide a conductive feature.

One of the sets 11,12 of machine readable regions may be applied to a security device, such as an elongate thread.

The security device may be either wholly embedded within the substrate 10, or partially embedded in the substrate 10 so that it is revealed at intervals in windows. Alternatively one or both of the sets 11,12 of the machine readable regions may be applied to one or more discrete security patches applied to either side of the substrate. The code may be formed by partly metallising/demetallising a carrier substrate such as PET to form the security device.

The design of a security document made from the security substrate 10 of the present invention may be such as to highlight the machine readable coding, or to camouflage it. The areas of coding do not have to interrupt the layout of the note. It is possible to have a design where only certain areas are formed from the coding material; this design could be all one colour. Examples of banknotes made from the substrate 10 of the present invention are illustrated in Figures 5 to 7. Figure 7 illustrates how an IMT variant may be integrated into the design.

Claims

CLAIMS: 1. A security substrate having at least two sets of regions having a machine detectable characteristic, in which only a first set of regions is applied to a first surface of the substrate, wherein the at least two sets of regions together form a machine readable code.
2. A security substrate as claimed in claim 1 in which a second set of regions is applied to a second opposing surface of the substrate.
3. A security substrate as claimed in claim 2 in which the first and/or second set of regions is applied to a security device applied to the surface(s) of the substrate.
4. A security substrate as claimed in claim 1 in which a second set of regions is applied to a security device at least partially embedded in the substrate.
5. A security substrate as claimed in any one of the preceding claims in which the machine detectable characteristic is magnetism.
6. A security substrate as claimed in any one of claims 1 to 4 in which the machine detectable characteristic is luminescence.
7. A security substrate as claimed in any one of claims 1 to 4 in which the machine detectable characteristic is conductivity.
8. A security substrate as claimed in any one of the preceding claims in which at least one of the sets of regions is printed.
9. A security substrate as claimed in any one of the preceding claims in which the machine detectable characteristic of each set of regions is detectable from either side of the substrate.
10. A security substrate as claimed in any one of the preceding claims in which the regions are visible to the naked eye.
11. A security substrate as claimed in any one of claims 1 to 9 in which the regions are invisible to the naked eye.
12. A security article incorporating a security substrate as claimed in any one of the preceding claims.
13. A security article as claimed in claim 12, wherein the article comprises one of banknotes, cheques, passports, identity cards, certificates of authenticity, fiscal stamps and other documents for securing value or personal identity.AMENDMENTS TO THE CLAIMS HAVE BEEN MADE AS FOLLOWSCLAIMS: 1. A security substrate having at least two sets of regions having a machine detectable characteristic, in which only a first set of regions is applied to a first surface of the substrate, wherein the at least two sets of regions together form a machine readable spatial code.2. A security substrate as claimed in claim 1 in which a second set of regions is applied to a second opposing surface of the substrate.3. A security substrate as claimed in claim 2 in which the first and/or second set of regions is applied to a security device applied to the surface(s) of the substrate.4. A security substrate as claimed in claim 1 in which a second set of regions is applied to a security device at least partially embedded in the substrate.5. A security substrate as claimed in any one of the preceding claims in which the machine detectable characteristic is magnetism.S:: 25 6. A security substrate as claimed in any one of claims 1 to 4 in which the machine detectable characteristic is * * S * S luminescence.7. A security substrate as claimed in any one of claims 1 ** 30 to 4 in which the machine detectable characteristic is conductivity.8. A security substrate as claimed in any one of the preceding claims in which at least one of the sets of regions is printed.9. A security substrate as claimed in any one of the preceding claims in which the machine detectable characteristic of each set of regions is detectable from either side of the substrate.10. A security substrate as claimed in any one of the preceding claims in which the regions are visible to the naked eye.11. A security substrate as claimed in any one of claims 1 to 9 in which the regions are invisible to the naked eye.12. A security article incorporating a security substrate as claimed in any one of the preceding claims.13. A security article as claimed in claim 12, wherein the article comprises one of banknotes, cheques, passports, identity cards, certificates of authenticity, fiscal stamps and other documents for securing value or personal identity.