AU2012234225B2

AU2012234225B2 - Security element for a value document, manufacturing method, and corresponding document

Info

Publication number: AU2012234225B2
Application number: AU2012234225A
Authority: AU
Inventors: Xavier Borde; Julien Gillot
Original assignee: Oberthur Fiduciaire SAS
Current assignee: Oberthur Fiduciaire SAS
Priority date: 2011-03-30
Filing date: 2012-03-28
Publication date: 2016-09-01
Anticipated expiration: 2032-03-28
Also published as: FR2973398B1; AU2012234225A1; EP2691573A1; RU2013148138A; KR20140026446A; CA2828398C; CN102729673A; KR101899528B1; WO2012130907A1; RU2586130C2; BR112013024902B1; CN102729673B; PL2691573T3; EP2691573B1; CA2828398A1; FR2973398A1; BR112013024902A2

Abstract

The present invention relates, in particular, to a security element (12) for a value document (1), which consists of an initially planar substrate (G), including an array (14) of raised lines (16), each raised line (16) comprising a profile (F), said profile (F) comprising gradual variations in the shape thereof along a predetermined line (16) or from one line to the other, said array (16) being colored, characterized in that said colored network (16) consists of repeating contiguous strips (3) formed by adjacent or contiguous threads (120, 121, 122) of at least two different colors (B, R, Y), said strips (3) being overall oriented in the same direction as that of said lines (16) of said array (14).

Description

SECURITY ELEMENT FOR A VALUE DOCUMENT, MANUFACTURING METHOD, AND CORRESPONDING DOCUMENT

The present invention relates to a security element for a document-value. It also relates to a production process of such a security element, as well as a document-value which comprises at least one such element.

The present invention applies more particularly to a security element for a document-value such as for example a fiduciary document or similar.

The expression "fiduciary document" means all documents such as bank notes, cheques, bank cards or the like for transmitting a sum of money.

The expression "similar document" means all documents issued by an administration of the state to attest to the identity of a person or his right to drive a vehicle, such as an identity card, a passport or a driving permit.

This expression also means any type of document which serves to authenticate an object of value, such as for example a label to be put on clothing. It also means any document serving to authenticate payment of tax, such as fiscal vignettes.

In such a field, and more particularly for bank notes, it is known to incorporate one or more security elements of varied nature to protect these documents from possible counterfeiting.

There are different types of security element, and more particularly those known as "first level".

Such a security element is intrinsically difficult to make, though at the same time easily identifiable by the public from simple attentive observation .

This security element often has a relatively complex graphic design, such as line printing, guilloches, a numismatic base, etc. It utilises various printing techniques such as offset, serigraphy, intaglio, flexography, typography, etc.

In particular, there is a greater interest within the scope of the present invention in a security element giving a moire effect.

In general, the moire is a visual interference phenomenon resulting for example from superposition of two networks of non-parallel lines.

Accordingly, in the field of bank notes, there are those known which have a security element formed from parallel lines in relief, as well as a network of parallel colour lines, oriented differently relative to the lines in relief.

According to the angle of observation, some colour and iridizing effects occur due to this moire phenomenon .

The state of the art relating to this technique can be illustrated by documents US 4 033 059, EP 1 580 020, EP 1 829 709 and EP 1 393 925.

The present applicant noticed that it was possible to get a particularly spectacular moire effect without having to necessarily use non-parallel networks.

Thus, a first embodiment of the invention relates to a security element for a document-value which is constituted by an initially planar support, comprising a network of lines in relief, each line in relief comprising a profile, said profile comprising variations of gradual form along a determined line or from one line to the other, said network being coloured, wherein said coloured network is constituted by a repetition of contiguous bands, formed by filaments of at least two different colours, adjacent or contiguous, these bands having the same direction as said lines of said network. "The same direction" means that the bands extend parallel to the lines of the network, but without excluding the situation in which a fraction of these bands extends in a different direction.

This invention is based on the ideas of French patent No. 2 942 811.

Because of the invention, an amplified optical effect relative to that described earlier is produced, visible to the naked eye. This is the first-level security .

But, observation by microscope of this security element reveals a different structure, more difficult to reproduce by forgers, due to the complexity of the resulting relief.

The invention consequently makes counterfeit bills detectable by microscope.

Second-level security is accordingly needed.

According to other advantageous and nonlimiting characteristics of this security element: - said variations are conformed so that the relief hides part of the filaments, when observed according to a angle not perpendicular to said plan, said part gradually varying along the line or from one line to the other, revealing a variation in colour and/or luminosity. - according to an angle of observation perpendicular to said plane, the width of said filaments is such that said at least two colours cannot be distinguished unmistakably from each other by the naked eye; - said variation in form is periodical, such as a variation in height of the profile; - said profiles comprise at least one flank, each defining an angle of inclination relative to a direction normal to the network, said variation in form comprising a variation in the angle of inclination of the flank by at least one line or at least two lines of the network, gradually along this line, respectively from one line to the other, so as to form a degraded optical effect of light reflection changing as a function of an angle of observation of the security element; - said profiles have a generally triangular form, two adjacent profiles each comprising a crest, separated by a furrow and said variation in form consists of a variation in the position of the crest between two adjacent furrows or a variation in the height of the crest; - said furrows are parallel to said bands; - the width of said bands is substantially equal to that of the lines in relief; - the width of the bands is between 50 and 2000 pm, preferably between 200 and 600 pm, more preferably still of the order of 400 pm; - the filaments of colour forming said band are of the same width; - over at least one portion of their range, said bands exhibit a different orientation so as to constitute at least one numismatic image; - a generally planar support is coated with said coloured bands and is deformed by means of an intaglio printing plate, by the embossing stamp technique, which presents a network of etched lines of a form complementary to that of a line of said network . A second embodiment of the invention relates to a production process of a security element such as the security element described hereinabove, wherein a generally planar support is coated with said coloured bands and in that it is deformed by means of an intaglio printing plate which has at least one etched furrow, of a form complementary to that of a line of said network.

Finally, the invention also relates to a document-value which comprises at least one security element such as the security element described hereinabove .

The security element is preferably integrated therein or is attached thereto.

This document-value is advantageously made of paper, fibrous material, plastic or a combination of at least two of these materials.

Other characteristics and advantages of the present invention will emerge from the following description of some preferred embodiments.

This description will be given in reference to the attached diagrams, in which:

Figure 1 is a simplified top plan view of a document-value consisting of a bank bill and comprising a security element according to a first embodiment of the invention;

Figure 2 is a highly enlarged top plan view of part of the security element evident in Figure 1, before it is deformed;

Figure 3A is a view in perspective of part of an etching plate resulting in a security element according to a first embodiment of the invention;

Figure 3B illustrates a view in perspective of three contiguous lines of a network integrated in the security element, according to a first variant embodiment of the invention, created with a plate such as described in reference to Figure 3A;

Figures 4A and 4B are equivalent views to the preceding figures of a plate and a security element, according to a second embodiment;

Figure 5A is a partial top plan view of the security element of Figure 1, after deformation;

Figures 5B and 5C are end views opposite the element of Figure 5A;

Figure 5D is a partial view in transversal section of the security element of Figure 5A at the level of the point of inflection referenced Si;

Figures 6 and 7 are end perspective views, respectively of a third and fourth embodiment of the invention;

Figure 8 is a top plan view of numismatic printing integrated into a security element such as that of the invention;

Figures 9 and 10 are highly enlarged views and on different scales of an intaglio printing plate producing the security element which appears in Figure 3B;

Figures 11 and 12 finally are highly enlarged views and on different scales of an intaglio printing plate producing the security element which appears in Figure 4B.

Throughout the present application, the numeral reference relative to the printing plates of the "prime" index will be used here conventionally. In these conditions, the same numeral reference, assorted or not of the "prime" index designates the same element of the plate, respectively of the security element.

Figure 1 illustrates a document of value 1 constituted by a bank bill.

Traditionally, and in the example presented here, the bill comprises on at least its rear face an indication of its value referenced 10 (in this case 100), and decor referenced 11, here representing a portrait. A security element 12 according to the invention is also visible on this bank bill 1, to the left of the portrait.

The document of value 1, in this case the bank bill, is made of paper or fibrous material, or again, according to a variant embodiment, plastic material or a combination of these materials.

The security element 12 is either attached to or integrated into the bill. In this latter hypothesis, this means that it is formed in a single piece with said bill.

This security element, as per a characteristic of the invention, comprises a coloured network constituted by repetition of contiguous bands 3 formed by adjacent or contiguous filaments, of at least two different colours.

In the case presented in Figure 2, each band is formed by three parallel filaments referenced 120, 121 and 122 respectively having different colours.

In this precise embodiment, the filaments 120 marked by small crosses present the colour blue referenced B.

The immediately contiguous filaments 121 illustrated here by small circles have a red colour referenced R.

Finally, the third filament 122, which is devoid of marking means in the Figure, is yellow and referenced J.

Of course, according to other embodiments, other combinations of colours could be selected.

The pitch (that is, the width of each band) and the width of each filament are referenced respectively by Pi and Li.

Preferably, according to an angle of observation perpendicular to the plane G containing the support of the security element, the width Li of the filaments 120 to 122 is such that the colours B, R and J cannot be distinguished from each other by the naked eye. In other terms, the eye perceives a combination of these colours.

In a particularly advantageous way, the pitch Pi is of the order of 400 pm, while the filaments 120 to 122 of a colour forming each band 3 are of the same width Li.

In another embodiment not shown, use could be made of a different number of colours, for example two or four.

These filaments are not necessarily contiguous; they can simply be adjacent.

In the case of the figure where the colour white is used, this colour results from absence of coloration or white coloration.

In the case of absence of coloration, in this case it is the colour white of the support which appears directly .

The security element 12 is preferably coloured by an offset type printing procedure.

Figure 3 partially illustrates, in perspective, a plate for producing a first embodiment of the security element according to the invention.

This plate comprises a network 14' of lines 16' in relief, substantially parallel. These lines 16' present, in transversal section, a triangular form.

The two flanks of these lines are designated by references 17Ά and 17'B.

Here, the angle of inclination a.'2 of the flank 17'B of a line 16' gradually varies along this line, while the angle of inclination a'1 of the flank 17Ά varies gradually in the inverse direction. The two flanks 17Ά and 17'B opposite two contiguous lines of the network 14' thus join up by forming a furrow 21' of constant depth. H' references the height of the reliefs, L'2 references the width of the lines 16' and 1/2T' references the half-frequency of variation of the above angles .

Figure 3B illustrates part of the security element resulting from the plate of Figure 3A. Its form is exactly the inverse (complementary) of that of the plate .

In this case, this security element comprises a network 14 of lines 16 in relief, substantially parallel. These lines 16 exhibit, in transversal section, a triangular form.

The two flanks of these lines are designated by references 17A and 17B.

Here, the angle of inclination eg of the flank 17B of a line 16 gradually varies along this line, while the angle of inclination eg of the flank 17A gradually varies in the inverse direction. The two flanks 17A and 17B opposite two contiguous lines of the network 14 thus join up by forming a furrow 21 of constant depth.

Naturally, the parameters H, L2 and 1/2T are strictly equal to H', L'2 and 1/2T'.

As illustrated in Figure 4A (second embodiment), the plate also comprises a network 14' of lines 16' in relief. Each line comprises at least flanks 17'A and 17'B defining an angle of inclination a'1 relative to a normal direction to the plane of the network 14' (this direction is sketched by an axis z on the Cartesian mark (x) , (y) and (z) indicated in the figures .

In this example, each line 16' has a general rectilinear form, and the lines 16' of the network 14' are parallel to each other.

The angle of inclination a'1 of the flank 17'A of at least one line 16' of the network 14' varies gradually along this line 16'.

Figure 4B illustrates part of the security element obtained by means of the plate of Figure 4A.

The angle of inclination og of the flank 17A of at least one line 16 of the network 14 varies gradually along this line 16 so as to form an optical effect in light reflection changing as a function of the angle of observation of the security element 12.

In fact, this gradual variation is of sinusoidal type.

The coloured grid described in reference to Figure 2 appears under this network.

In the two embodiments of Figures 3B and 4B, the pitch L2 of each line is equal to the pitch Pi of the coloured network of Figure 2.

Figure 4B also illustrates the coloured grid of Figure 2.

Figure 5A is a top plan view, under microscope, of a security element integrating both a coloured network and a deformed network.

It is evident that this deformation is realised by embossing of the support, in particular according to the so-called embossing stamp technique, specifically inkless intaglio.

This figure reveals the presence of juxtaposition of contiguous bands of colour, specifically three different colours.

In this embodiment, the furrows 21 which separate each line 16 are always at the same altitude and rectilinear, while the crest 20 moves according to a sinusoid S whereof the point of inflection is referenced Si.

In this figure, the eye of an observer is referenced by the Figure 15, which laterally looks at the security element under intense lighting.

The periodical character of the inclination of the flanks translates by two phenomena.

On the one hand at some angles, the flanks are oriented orthogonally to the direction of observation, which maximises the surfaces observed. On the other hand, the crest masks the opposite flanks. Given that this crest is periodical and moves, the colours of filaments of the bands are exposed alternatively.

Also, the fact that paper is deformed by embossing translates a certain plasticity thereof. But, by deforming it, the trajectory of a point which transversally runs through the embossed network is also mathematically extended.

With respect to the coloured filaments, the same phenomenon recurs. The width of the bands formed by three contiguous filaments measures 400 pm for example. The lines of the etching plate have an identical width of 400 pm, but due to the fact of the adding of a third dimension, in this case the depth, the trajectory for connecting the two transversal ends of said lines is increased. On the support, by admitting for example that in a line of given section (perpendicular to the direction of extension of lines of the network), a filament of blue colour is above a crest and extends on either side of this crest, if this moves along the section line, the blue filament will progressively pass from one side or the other as a function of the direction of displacement and leave space for the contiguous filament.

All these phenomena collaborate in the appearance of a moire effect translating by spectacular macroscopic irisation, visible to the naked eye, colours constituting the filaments and therefore to authenticate the security element and the document on which it is affixed.

Figures 5B, 5C and 5D illustrate the profiles of deformations of two contiguous lines 16. In views 5B and 5C, each line has the form of a rectangular triangle; while in Figure 5D there is a profile in the form of an isosceles triangle.

Of course, the resulting visual effect depends on the height H of the reliefs, the period T of the sinusoidal evolution of the inclination of the flanks of the reliefs and the pitch P of angular variation of said flanks .

Figure 6 illustrates another embodiment in which the reliefs of each line have a section in the form of an isosceles triangle, the crest of the latter shifting in height according to sinusoidal progression.

In the embodiment of the Figure 7, use is made of a progression of lines according to stair steps of progressive height.

Figure 8 illustrates, within a network of bands of colour, an impression N of numismatic type made of a fraction of bands oriented in an arc of a circle. Together they constitute a numismatic image in a C form.

Figures 9 and 10 show a top view of the electronic microscope, an intaglio printing plate corresponding to the embodiment of Figure 3A. This plate is etched according to patterns complementary to those to be produced on the security element.

Similarly, Figures 11 and 12 illustrate, top plan view by electronic microscope, an intaglio printing plate corresponding to the embodiment of Figure 4A.

The following parameters preferably have the values indicated hereinbelow:

Period of periodical movements: T is between 0.5 and 50 mm, preferably between 5 and 25 mm.

Depth of the etching on plates: P is between 1 and 200 microns, preferably between 40 and 150 microns, particularly 100 microns.

Width Lg of the etching on plates: Lg is between 50 and 2000 microns, preferably between 200 and 600 microns, particularly 400 microns.

Width Lf of the filaments and Lb of the bands: Preferably Lb = n x Lf (width filaments) with n > 2.

Preferably η = 3 and Lf = Lg/n. If Lg = 400 pm and n = 3, then Lf = 133,333 pm and Lb = 400 microns.

Different widths Lf are also feasible, provided that ELf = Lg.

The lines embossed with periodical movements are not necessarily transversally aligned. They can be offset line by line.

The colours of the filaments can accumulate second-level properties (fluorescent, phosphorescent, infrared, thermochromic, marker inks etc.).

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.

Claims

Claims

1. A security element for a document-value which is constituted by an initially planar support, comprising a network of lines in relief, each line in relief comprising a profile, said profile comprising variations in gradual form along a determined line or from one line to the other, said network being coloured, wherein said coloured network is constituted by repetition of contiguous bands, formed by filaments of at least two different colours, adjacent or contiguous, these bands having the same direction as said lines of said network.
2. The security element as claimed in Claim 1, wherein said variations are conformed so that the relief hides part of the filaments, when observed according to a angle not perpendicular to said plan, said part gradually varying along the line or from one line to the other, revealing a variation in colour and/or luminosity .
3. The security element as claimed in any one of Claims 1 or 2, wherein according to an angle of observation perpendicular to said plan, the width of said filaments is such that said at least two colours cannot be distinguished unmistakably from each other by the naked eye.
4. The security element as claimed in any one of the preceding claims, wherein said variation in form is periodical, such as a variation in height of the profile .
5. The security element as claimed in any one of the preceding claims, wherein said profiles comprise at least one flank each defining an angle of inclination (ai) relative to a direction normal (z) to the network, said variation in form comprising a variation in the angle of inclination (op) of the flank by at least one line or at least two lines of the network, gradually along this line, respectively from one line to the other so as to form a degraded optical effect in light reflection, changing as a function of an angle of observation of the security element.
6. The security element as claimed in Claim 5, wherein said profiles have a generally triangular form, two adjacent profiles each comprising a crest, separated by a furrow and in that said variation in form consists of a variation in the position of the crest between two adjacent furrows or a variation in the height of the crest.
7. The security element as claimed in Claim 5, wherein said furrows are parallel to said bands.
8. The security element as claimed in any one of the preceding claims, wherein the width of said bands is substantially equal to that of the lines in relief.
9. The security element as claimed in any one of the preceding claims, wherein the width of the bands is between 50 and 2000 pm.
10. The security element as claimed in any one of claims 1-8, wherein the width of the bands is between 200 and 600 pm.
11. The security element as claimed in any one of claims 1-8, wherein the width of the bands is of the order of 400 pm.
12 . The security element as claimed in any one of the preceding claims, wherein the filaments of colour forming said band are of the same width.
13. The security element as claimed in any one of the preceding claims, wherein over at least one portion of their range said bands exhibit a different orientation so as to constitute at least one numismatic image .
14. A production process of a security element as claimed in any one of the preceding claims, wherein a generally planar support is coated with said coloured bands and in that it is deformed by means of an intaglio printing plate which has at least one etched furrow, of a form complementary to that of a line of said network.
15. The document-value wherein it comprises at least one element as claimed in any one of Claims 1 to 13.
16. The document-value as claimed in Claim 15, wherein the security element is integrated therein or is attached thereto.
17. The document-value as claimed in any one of Claims 15 or 16, wherein it is made of paper, fibrous material, plastic or a combination of at least two of these materials.