EP2753753B1 - Security ribbon and security document comprising it - Google Patents

Description

The present invention relates to a security strip intended to be incorporated in part in the structure of a security document at least partially made of fibers.

It also relates to a security document that is provided.

To guard against counterfeit security documents such as banknotes, it has been proposed the use of various security means such as watermarks, fibers, boards, etc.

Other techniques consist in introducing into the paper of the security document an elongated element made of synthetic material forming "security thread", making it possible to further increase the difficulty of manufacturing counterfeit products, but also to facilitate the authentication of the document by a "lambda" user, in other words "the man in the street".

The first threads introduced into the paper were "drowned", which means that they are trapped in the mass of the paper, being incorporated during the manufacture of the notes. They were designed so that they are invisible in reflected light and visible in transmitted light, that is to say by transparency.

Since then, papermakers have developed numbers of threads of different types. They are, for example, colored and magnetic wires carrying machine-readable, intermittently coded, fluorescent, partially demetallized, micro-printed, holographic, etc. information.

According to a more recent technique, it has been proposed to incorporate the security thread so that it is visible by reflection only in the form of a set of windows. This means that this thread is embedded in the mass of the paper so that it is sometimes embedded in the mass, sometimes flush with the surface of one of the faces of the ticket, which explains the use of the term "windows" .

Thus, the windows are visible by reflection, while the "immersed" parts are only visible by transmission. By the term "reflection" is meant the phenomenon by which the rays of incident light are reflected on the surface of the support. Patent is also known WO2005069231 introducing two parallel threads on two separate tracks. This makes it possible to increase the size and the number of zones of visible threads. However, there are many restrictions on the use of such technology. In the first place, a minimum distance between two wires must be respected for manufacturing reasons. In addition, there is a difficulty of locating between the patterns of the son. In addition, the process of managing simultaneous and synchronized placement of two threads in the paper of the security document is cumbersome and complex. Finally, the presence of two son in the support results in a significant deformation of the latter.

The present invention aims to overcome these disadvantages by providing a strip which comprises two zones giving the illusion of being made of two different son and whose particular optical effects make fraudulent imitation particularly complex.

Thus, the present invention relates to a safety strip intended to be incorporated in part into the structure of a security document at least partially made of fibers, this strip emerging on the surface of said document in the form of a set of windows, and comprising a transparent or translucent support material, covered, on one of its faces, said "upper face", a visible coating by reflection, and which comprises a longitudinal strip at least partially free of said coating, which separates a first and a second son areas, covered with said coating characterized by the fact that each of said son zones respectively have two different optical renditions and / or effects reflected by reflection, and that they have negative patterns which are in register respectively with each other, that is to say that at least one pair of these patterns in registration always the same spacing pitch as it repeats along said zones.

Thanks to this combination of characteristics, the person who observes the security document in which this banner is integrated, has the illusion of having to deal with two different threads, because they combine respectively two different renditions and / or optical effects. . This phenomenon is combined with the identification of the motifs contained therein. In effect, the designs and / or messages contained in these patterns are invariably positioned relative to each other. others, and "respond" via axial or central symmetries, or even by translations or complement each other.

• ladite bande longitudinale présente des bords droits et parallèles ;
• ladite bande longitudinale présente des bords non droits et/ou non parallèles ;
• ledit revêtement comprend au moins deux couches choisies parmi les suivantes : couche d'encre optiquement variable, magnétique ou non, couche d'encre à effet iridescent, couche holographique, couche métallique, couche d'encre opaque ;
• le bandeau comporte, entre ledit matériau support et ladite couche métallique, une couche transparente, sans effet optique, cette couche présentant une épaisseur différente dans chacune desdites zones formant fil, ainsi qu'une couche absorbant la lumière ;
• au moins une impression de couleur noir et/ou au moins une couche obtenue par dépôt sous vide s'étendent sur la face inférieure dudit matériau support, de sorte qu'elle est au moins partiellement visible par transmission ;
• ladite bande est revêtue partiellement d'une couche opaque ou métallique, le taux de couverture de cette bande étant préférentiellement inférieur ou égal à 50% de sa surface.

According to other advantageous and nonlimiting features of the invention:

• said longitudinal band has straight and parallel edges;
• said longitudinal strip has non-straight edges and / or non-parallel;
• said coating comprises at least two layers selected from the following: optically variable ink layer, magnetic or not, iridescent effect ink layer, holographic layer, metal layer, opaque ink layer;
• the strip comprises, between said support material and said metal layer, a transparent layer, without optical effect, this layer having a different thickness in each of said wire zones, as well as a light absorbing layer;
• at least one black color printing and / or at least one layer obtained by vacuum deposition extend on the underside of said support material, so that it is at least partially visible by transmission;
• said strip is partially coated with an opaque or metallic layer, the coverage ratio of this strip being preferentially less than or equal to 50% of its surface.

Another aspect of the invention relates to a security document, such as a bank note, a passport or the like.

This document is remarkable in that it incorporates a strip according to one of the characteristics identified above, which is incorporated within it, while emerging on the surface of at least one of its visible faces under the form of a set of windows.

Preferably, the underside of the strip is covered with a layer of ink of the same color as that of the material which constitutes the document.

• la figure 1 est une vue partielle de dessus, d'un document de sécurité, en l'occurrence un billet de banque, dans lequel est incorporé partiellement un bandeau, les motifs qu'il comporte n'y étant toutefois pas intégrés;
• les figures 2 à 4 sont des vues en coupe transversale de trois formes de réalisation dudit bandeau (sur ces figures, on notera que, pour ne pas les alourdir inutilement, seuls sont représentés les éléments qui recouvrent la face « supérieure » du matériau support du bandeau) ;
• la figure 5 est une vue équivalente à la figure 1 d'encore un autre mode de réalisation d'un billet ;
• les figures 6 à 8 sont des vues de dessus de trois autres variantes du bandeau, la dernière d'entre elles montrant le bandeau sous forme de fenêtres ;
• enfin, les figures 9 à 12 sont des vues d'encore quatre formes de réalisation du bandeau de l'invention.

Other characteristics and advantages of the invention will appear on reading the following description of a preferred embodiment of the invention. This description is made with reference to the appended drawings in which:

• the figure 1 is a partial view from above, of a security document, in this case a banknote, in which is partially incorporated a band, the reasons it comprises are however not integrated;
• the Figures 2 to 4 are cross-sectional views of three embodiments of said strip (in these figures, it will be noted that, not to unnecessarily weigh down, only the elements that cover the "upper" face of the support material of the strip) are represented;
• the figure 5 is a view equivalent to the figure 1 another embodiment of a ticket;
• the Figures 6 to 8 are top views of three other variants of the banner, the last of them showing the banner in the form of windows;
• finally, Figures 9 to 12 are views of yet another embodiment of the strip of the invention.

Throughout the present application, the term "zones with different optical effects" means zones which, visually, with the naked eye and by reflection, can be differentiated from each other. These are for example areas having a color change between two shades depending on the inclination of the support or accompanied by different diffraction effects of the light. In the embodiment in which the optical effects are the same, then the renderings will be different, which then only results in different color changes within the two wires.

The strip 1 according to the invention is represented at figure 1 annexed, partially integrated in a security document 2 which consists here of a banknote. According to a variant not shown, it could be another type of security document such as a passport.

This security document is preferably based on cotton paper, with or without chemical pulp, cellulose-based paper or any other material containing fibers of different types and weights. It is also possible to use a hybrid support combining polymer (s) and paper.

As is well known in the art, the strip 1 is partially incorporated in the document 2, while emerging at its surface in the form of a set of windows F.

This strip 1 comprises a central longitudinal strip 3 which separates from one another and delimits two son areas 4 and 4 'with straight and parallel edges. This gives the observer the illusion that the "threads" are separate and independent of each other.

As will be seen below, each zone 4 and 4 'is covered with a coating and each of them has optical renders E01 and E02 distributed in different regions. The effect E01 is for example given by a magenta color coating that switches to green, while the E02 effect is given by a green color coating that switches to blue.

The reasons presented by this banner are not represented here, as already mentioned above.

As shown in figure 2 and according to a first embodiment, the strip according to the invention consists of a transparent or translucent support material 5, such as a plastic film. This is preferably polyester, for example with a thickness of about 10 microns. On the "outer" lower face 51 of the strip (ie that which is turned towards the core of the document, paper side), it is preferably coated with a layer of ink of the same color as the paper (by example of a thickness of about 2 microns). If this layer of ink is not applied, then at least partially the layers on the upper surface are seen. In other words, this ink has a masking function.

Finally, an outer adhesive layer approximately 4 to 5 μm thick is affixed to the assembly, on the side of the face 51.

It is intended to improve the attachment of the banner to the paper. Note that these two layers have not been represented at figure 2 .

On the opposite face of the strip 1 (window side) is deposited an opaque ink layer 7, preferably black, by any known printing technique (preferably by gravure).

Reserves 70 can be made in this print so as to create a pattern M called "negative pattern".

Throughout the present application, the term "motif" means any design or character, whether alpha numeric or not. The term "negative" means that it is delimited by a different contrast zone or contour, in this case higher. In other words, this zone or contour is visually reversed with respect to the subject.

Preferably, the central strip is largely free of ink so as to delimit two distinct zones 4 and 4 '.

On zones 4 and 4 'is applied an optically variable layer. This is achieved by printing, for example, an OVI® or SICPASTAR® ink from SICPA. Preferably, inks 4 and 4 ', inks having different optical effects will be deposited. The transparent parts of the strip 1 (that is to say the parts devoid of opaque ink and / or metal deposition) will not have an optical effect of color change, unlike the portions of the strip in line with opaque areas.

Depending on the structure represented in figure 3 , create the same effect by depositing a thin layer 7 of a metal, for example aluminum or copper (creating a mirror effect) by any known technique of vacuum deposition, then de-metallization partial to create negative patterns. A transparent layer 8, without particular optical effect is then deposited in controlled thickness, and a layer 9 'of an absorbent material of Inconel type (registered trademark). The color of the optical effect produced will depend on the thickness of this layer 8.

Subsequently, a metal layer 9, for example of the chrome type, is deposited under vacuum, so that this layer 9 is in line with a metal zone 7. There is a color change effect during the modification of the angle of observation.

On the opposite side of the wire (window side), it comes to deposit an adhesive of about 2 microns thick. Depending on the level of resistance required, a polyester film approximately 10 μm thick can be laminated in order to give the strip and its associated layers sufficient physicochemical resistance. A primer (if needed) and a final adhesive layer about 4 to 5 μm thick is deposited to ensure proper and sufficient adhesion between the strip and the paper fibers.

In a preferred embodiment not shown, the central strip 3 devoid of coating and separating the strip into two distinct areas is printed using a second level security ink selected from fluorescence inks, phosphorescence, visible infrared etc. This impression is easily visible through the central strip 3.

In another preferred embodiment visible to the figure 4 , the central strip 3, devoid of optically variable material, may be previously coated with an opaque layer or metal type 7 itself partially "hollowed out" of material so as to create negative M-patterns. By the terminology "partially hollowed out" is meant that the coverage rate of said band is less than or equal to 50%.

These patterns will be difficult to see in reflection but easily visible by transparency. They are arranged so that they are in perfect registration with the zones 4 and 4 'optically variable. These patterns can take various forms such as blocks, and can be arranged in a periodic and repetitive manner.

Still in a preferred embodiment, these arrangements can create a sequence of "bar code" type automatically readable by a machine.

The opaque black ink may also have a conductive nature of the electric current. In this case, the printed pattern must be continuous in the longitudinal direction of the strip on one or other of the zones 4 and 4 'to ensure electrical conductivity. This electrical conductivity can be read and detected by a sorting machine.

In yet another preferred embodiment, the patterns formed on the first and second distinct areas 4 and 4 'complement each other so as to form an overall pattern, the two parts of which are perfectly in register. It should be noted that this third embodiment would be particularly difficult to achieve if it were to be achieved by incorporating two separate son.

In the following description will be detailed the embodiments of the Figures 5 to 8 . It should be noted that the dimensions noted therein are not limiting in nature. However, as regards the width of the strip, it is preferably between 1 and 6 mm.

To the figure 5 is visible a security strip 1 with a width of 4 mm, incorporated in windows in a banknote 2. It is coated with an optically variable ink magenta / green visible in zone 4 and green / blue in zone 4 . The strip has a band 3 devoid of material, a width of 1 mm separating the strip 1 in two disjoint parallel areas 4 and 4 '. Areas devoid of material are also arranged on each of the two bands 4 and 4 'in register with each other so that they form patterns exactly opposite each other.

However, we can consider the case where they are not exactly opposite, but shifted longitudinally of the same step of constant value over the entire longitudinal extent of the son areas.

To the figure 6 is visible a safety strip 1 with a width of 4 mm coated on the one hand, an optically variable green / magenta ink and secondly an optically variable ink magenta / green. The strip 1 has a band 3 devoid of material, a width of 1 mm, separating the strip 1 into two disjoint parallel areas 4 and 4 '. M negative units are arranged in register with each other respectively on one and the other of the zones 4 and 4 '. In the central strip 3, an opaque ink forms patterns M 'in negative. These patterns are arranged in sequence of repetitive blocks. This sequence is slightly visible in reflection in the surface areas of the paper and easily visible in transmission.

To the figure 7 is visible a safety strip 1 consisting of two holographic zones 4 and 4 'having a diffractive effect of blue to red (through all the other colors of the visible spectrum) and a diffractive effect of red to blue. The strip 1 has a band 3 without coating 1 mm wide, separating parallel areas 4 and 4 '. Patterns are arranged in register with each other respectively on one and the other of the zones 4 and 4 '.

In the central strip 3, an opaque ink creates negative patterns M '. These patterns are arranged in sequence of repetitive blocks. This sequence is slightly visible in reflection in the surface areas of the paper and easily in transmission.

The figure 8 still represents an embodiment of the strip, partially integrated in the paper of a security document. We are dealing here with an area 4 which has areas with a change of colors as in the previous embodiments and a zone 4 'with diffractive effect. Along the central strip 3 are printed patterns of black color (and therefore not optically variable) together forming a kind of bar code. As is apparent from the foregoing, the invention makes it possible to obtain a "double-wire" visual effect by using a single strip. This visual effect is authenticated by the general public. The distinct areas created by the absence of core material, incorporate color change and / or metallization effects. This combination of effects is visible on the surface of the paper, in windows. Patterns created on one or other of the zones can be set perfect tracking. They can also form a "barcode" type sequence and provide a second level of security.

The banner of the figure 9 has two zones 4 and 4 'of different width, the central strip 3, with straight and parallel edges being offset with respect to the longitudinal central axis of the strip. Note the presence of patterns M and M ', the latter being negative, which together form a drawing, which here consists of the representation of a trombone. All the patterns of the bands 4 and 4 'is, of course, in registration. Band 4 varies from green to purple, while band 4 'has a purple metallic appearance.

To the figure 10 we are dealing with two zones 4 and 4 ', separated by a band 3 whose longitudinal edges are not straight, but "wavy", that is to say slightly curved, convex portions being alternated with concave portions . Band 4 varies from red to green, while band 4 'varies from blue to green.

To the figure 11 is shown an embodiment in which the strips 4 and 4 'each have sawtooth edges, so it is the same for the central strip 3. The strip 4 has a metallic appearance of copper type, while that the band 4 'has a metallic appearance of aluminum type.

Finally, at the figure 12 we are dealing with two bands 4 and 4 'of very different shape and appearance. The bottom of each has a metallic appearance of aluminum type whose density varies along each of the bands. The band 4, wider than the band 4 ', comprises multiple multicolored patterns. The edges of the strip 3 are formed of a succession of portions of a circle, a long circular negative, repeated in this band, part of one of these portions of a circle.

Claims (9)

1. A security strip (1) designed to be incorporated in part in the structure of a security document (2) at least partially comprising fibres, this strip emerging at the surface of said document in the form of a set of windows (F), and comprising a transparent or translucid support material (5), covered on one of its faces (50), so-called « upper face », by a coating (R) visible by reflection, and which comprises a longitudinal strip (3) at least partially devoid of said coating (R), which separates a first and a second zones (4, 4') forming threads, covered by said coating (R), characterised in that each of said zones forming threads (4, 4') has respectively two different renderings and/or optical effects (E01,E02) visible by reflection, and in that it comprise designs (M) in negative which are respectively tracking each other, that is, at least one pair of these tracking designs (M) always has the same spacing when it is repeated along said zones.
2. The strip as claimed in Claim 1, characterised in that said longitudinal strip (3) has straight and parallel edges.
3. The strip as claimed in Claim 1, characterised in that said longitudinal strip (3) has non-straight and/or non-parallel edges.
4. The strip as claimed in Claim 1, characterised in that said coating (R) comprises at least two layers (6,9) selected from the following: layer of optically variable ink, magnetic or not, layer of ink with iridescent effect, holographic layer, metallic layer, opaque layer of ink.
5. The strip as claimed in Claim 2, in which said coating comprises a metallic layer (9), characterised in that it comprises, between said support material (5) and said metallic layer (9), a transparent layer (8), without optical effect, this layer (8) having a different thickness in each of said zones forming a thread (4, 4'), and a light-absorbing layer.
6. The strip as claimed in any one of Claims 1 to 3, characterised in that at least one printing of black colour and/or at least one layer obtained by deposit under vacuum extends on the lower face (51) of said support material (5), such that it is at least partially visible by transmission.
7. The strip as claimed in any one of the preceding claims, characterised in that said strip (3) is coated partially by an opaque or metallic layer, the coverage rate of this strip being preferably less than or equal to 50% of its surface.
8. A security document (2), such as a banknote, characterised in that it integrates a strip (1) as claimed in any one of Claims 1 to 5, which is incorporated within the latter, while emerging at the surface of at least one of its visible faces (50, 51) in the form of a set of windows (F).
9. The security document (2) as claimed in Claim 8, characterised in that the lower face (51) of said strip (1) is covered by a layer of ink of the same colour as that of the material comprising said document.

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