EP1716289B1 - Relatively-small security elements, production method thereof, sheet and security document comprising same - Google Patents

Abstract

The flakes, which are flat and of relatively small format, preferably 1 - 4 mm in size, are made with authentication motifs on both sides that are visible under natural or artificial light. The motifs can be colours, geometrical or alphanumerical designs, printed on flakes of circular, triangular, oval or other shape, with a preferable print weight of 2 - 5 g/sq m. They can be designed to be be visible under UV or infrared light, or be made luminescent, especially fluorescent or phosphorescent, thermochromic or piezochromic, contain DNA tracers or other means of identification. The flakes can be added to paper used for making security document that can have a backing of paper, a non-woven material, plastic film or a combination of these.

Description

The invention relates to flat and relatively small format security elements, of the wafer type, as well as the security documents comprising said elements and the method of manufacturing said elements.

In security documents, there are small format security elements known as planchettes for authenticating documents. The boards are similar to confetti having various shapes for example circular, hexagonal. It is advantageous for these boards, and therefore the material in which they are cut, to exhibit surface optical effects such as iridescence or dichroism and / or luminescence and in particular fluorescence, reflection or polarization of light. These effects are obtained for example by printing or inclusion of specific compounds. In addition, these boards may include authentication agents.
These boards are generally made by cutting a sheet or a plastic film or a sheet of paper or a complex, by a sequential process of stamping by punches or pins of a flat sheet. These boards have a size of the order of 1.5 mm. The sheets are plastic sheets and / or light weight paper. When they are based on a sheet of paper, it may be a so-called overlay sheet, usually used as a protective sheet in the field of decorative laminated papers; this sheet is traditionally manufactured by draining an aqueous suspension of slightly refined cellulose fibers, of the order of 20 ° SR (Schoepper-Riegler degrees), and containing a moist, non-opacified and low basis weight resistance agent, of the order of 25-40 g / m ² , and a thickness between 50 and 100 microns. They may include an agent improving their wettability and / or heat-sealing varnish facilitating their holding in the paper. Other types of papers can be used. Each board is in general of a single color.

To manufacture security papers or paper for bank notes, containing boards, the boards are introduced into the aqueous dispersion containing cellulose fibers or synthetic fibers and other additives commonly used in the papermaking technique. When the aqueous suspension is drained on a fabric of a round-form or flat-table paper machine called Fourdrinier, a number of boards are placed on the surface of the sheet of paper thus formed, and then the sheet is dried. .
Security documents comprising boards are described for example in patents EP342929 , EP546917 , EP544611 or US4037007 .

It is also known to introduce luminescent security fibers, in particular fluorescent, and therefore also visible in UV light, of different colors, in security documents, in particular banknote papers. These fibers are small plastic cylinders obtained most often by extrusion. A disadvantage of these traditional cylindrical security fibers is that they can create extra thicknesses or printing problems in the document if they are too big.

International demand WO 96/35586 describes security articles, for example boards or security threads, placed on security documents and having magnetic elements placed on a plastic substrate, for the authentication of security documents.

The patent application CN 1157790 relates to a bottle cap having a hidden pattern for preventing counterfeiting.

The European patent application EP 0 518 740 relates to a security document comprising a security thread visible in transmitted light, including iridescent marks that can appear in windows on the sides of the document.

French patent FR 1 413 910 relates to a security thread or security tape which may include, in particular, a printed design, letters or network.

The French patent application FR 2,593,840 relates to the use of a marking means comprising a fluorescent substance in a security paper.

The Japanese patent application JP 2001-159096 relates to the use of small pieces of paper, possibly colored, dispersed within the substrate of a security document.

We constantly search in the field of security documents to improve their level of security.

The Applicant therefore proposes security elements whose level and security possibilities have been increased compared to existing ones and which can be introduced into the documents, especially during the manufacture of the substrate.

It proposes for this purpose flat security elements having one or more reasons or means of authentication and a relatively small format such that they are easy to introduce during the manufacture of the substrate of the security document.

The invention therefore relates to a flat safety element in the form of a board, having a front face and a reverse side, which is characterized in that it comprises, printed on each of its faces, at least one identified authentication pattern and / or an authentication pattern resulting from the combination and / or superposition of a pattern on its front face and a pattern on its reverse side, at least one of said authentication patterns being at least partly observable in transmitted light.

Said element therefore comprises an authentication pattern observable in transmitted light (transvision) which may be the marked pattern and / or a pattern resulting from the combination and / or superposition of the front and back patterns. The patterns on the front and back can be marked patterns and / or also have an authentication pattern function.

According to a particular case of the invention, said identified authentication pattern is identified either with respect to at least part of the form of said security element or with respect to at least part of said patterns. It can be a combination of colors identified between them. For example, we can make a pattern representing the image of the flag of a country, stripes of different colors.

Preferably, at least one of the patterns (the pattern spotted, the pattern on the front, the pattern on the back or the pattern resulting from the front and back patterns) is visible to the naked eye that is to say without apparatus magnifying, however this observation with the naked eye may require the aid of a pattern-revealing device such as a UV source if the pattern is fluorescent or phosphorescent or a source of infra-red rays if the pattern is sensitive to this type of radiation.

According to a particular case of the invention, said security element has as motif on the front at least one given color and as backside pattern at least one other given color, said authentication pattern observable in transmitted light being the color resulting from the color of the back and color of the front. The colors on the front and back can also have an authentication role.

Preferably, the colors of the front and back are chosen from the primary colors.

According to another particular case of the invention, said security element is such that at least one of said patterns is a pattern in the form of a geometric pattern, in particular in alphanumeric form and / or frame and / or lines and / or points. In this case, said pattern observed in transmitted light may result from the combination and / or juxtaposition of the patterns present on the front and back of said element.

Preferably, the security element according to the invention is such that its dimensions are between 0.5 and 6 mm, preferably between 1 and 4 mm.

These security elements can be of any possible geometric shapes, in particular they can be square, rectangular, triangular, circular, oval, star, moon or curved edges for example sinusoidal type.

According to a particular case of the invention, the security element comprises prints at a rate of 1 to 10 g / m ² per side, preferably about 2 to 5 g / m ² per side by dry weight.

More particularly, the security element comprises patterns selected from patterns visible in natural light, visible under UV light, luminescent, in particular fluorescent or phosphorescent, detectable by infra-red radiation near or medium, thermochromic, piezochromic, tracer-based DNA, optically variable, in particular iridescent or based on liquid crystals or diffraction gratings or electromagnetic moire or holograms, or combinations thereof.

In particular, said security element according to the invention comprises, under or next to said patterns, impressions of electromagnetic character, especially magnetic and in particular continuous tracks or codes in the form of magnetic bits.

According to a particular case of the invention, the security element comprises chemical reagents for authentication or reagents revealing a specific event.

The security element according to the invention has as support, a sheet of paper or nonwoven, a plastic film or a complex of these materials.

In a particular case, said element is based on a carrier of low basis weight, in particular 25-40 g / m ² , and / or a thickness of about 50 to 100 microns.

More particularly, said support is a paper based on low-quality cellulose fibers of the overlay type.

In another particular case, the plastic film of said element is a polyester film.

According to a particular case of the invention, said element is based on a bulk opacified support or a support comprising on at least one of these faces, at least in part a layer or an impression, in flat or partial , opacifying or barrier.
The opacification / barrier makes it possible to suppress, in the case where it is desired, the interpenetration or interference of the impressions made on the front and back sides in reflected light. Indeed, in the case of thin and porous substrates such as thin overlay paper, the inks penetrate into the paper and migrate partially from one face to the other and therefore interfere, which is not necessarily desirable or in the case with opaque or even transparent supports, the effects may interfere, however a certain transparency can be maintained if it is desired to have an observable effect in transmitted light. In a particular case the opacification can be realized only partially on the element, thus one can have an element with a part without observable effect in transvision and a part with an observable effect in transvision.

The invention also relates to a security sheet comprising a fibrous substrate including several flat security elements, having a front face and a reverse side, and a relatively small format such as a clipboard, said element being as described above. For example, the security document may comprise between 5 and 20 of said elements.

In particular said security elements are arranged in band and / or distributed randomly within said substrate.

The invention also relates to a document or security article obtained from said security sheet.
Security element means any security purpose such as the security elements traditionally used in security documents (valuable papers such as banknotes, checks, coupons, restaurant vouchers) but also for other security applications. secure papers related to hygiene and / or medical and / or traceability, to the safety of people such as to indicate a specific event as an expiry date.
Security document means the usual documents such as banknotes, checks, tickets to sports or cultural events, securities, identity documents. It can also be a security article such as a packaging, a label or any other product including a sheet and which must be authenticated.

• on imprime au moins une partie desdits motifs d'authentification en une ou plusieurs étapes sur une des faces d'un support présentant une certaine transparence,
• on imprime, sur l'autre face, en une ou plusieurs étapes, au moins une partie desdits motifs d'authentification soit par repère par rapport à la forme dudit élément soit par repère à la partie imprimée précédemment.

The invention also relates to the method of manufacturing said security elements, which is characterized in that:

• at least a portion of said authentication patterns are printed in one or more steps on one of the faces of a medium having a certain transparency,
• one or more steps are printed on the other side, at least part of said authentication patterns either by reference to the shape of said element or by reference to the previously printed part.

In addition, the printed media is cut to the mark in security elements according to the desired form and such that at least the marked pattern is present in full on said element.

Preferably, after printing and before cutting, the printed sheet or film may be covered, in particular by means of printing, with a varnish heat sealing to ensure the holding in the substrate of the security document that will include them.

• on fabrique le substrat fibreux du document sur une machine à papier en introduisant lesdits éléments de sécurité tels qu'obtenus précédemment,
• on traite éventuellement la surface du substrat en presse encolleuse ou par couchage,
• on sèche le substrat obtenu,
• on découpe le substrat en feuilles de grand format ou on le bobine en une feuille continue,
• on imprime les feuilles découpées ou la feuille continue de manière appropriée à l'usage du document,
• on découpe la/les feuille(s) imprimée(s) au format dudit document, éventuellement au repère par rapport aux dits motifs d'authentification.

A security document comprising a fibrous substrate including at least one security element as described above can be manufactured according to the following method:

• the fibrous substrate of the document is manufactured on a paper machine by introducing said security elements as obtained previously,
• the surface of the substrate is optionally treated in a gluing press or by coating,
• the substrate obtained is dried,
• the substrate is cut into sheets of large format or is wound into a continuous sheet,
• the cut sheets or the continuous sheet are printed appropriately for the use of the document,
• the printed sheet (s) is (are) cut in the format of the said document, possibly at the reference point with respect to the said authentication reasons.

EXAMPLES

As a first example, we will describe below the realization of a security element according to the invention and a security paper containing it.
An overlay-type paper sheet is produced according to the traditional method by draining an aqueous suspension of slightly refined cellulose fibers, of the order of 20 ° SR (Schoepper-Riegler degrees), and containing a wet strength agent, not opacified and having a thickness of 70 microns. This sheet has a certain transparency.
The front face is printed in a blue fluorescent color and the back side in a yellow fluorescent color. A wetting improving agent and a heat-sealing varnish are applied on the surface to facilitate their holding in the paper.
The sheet obtained is cut into fibrettes, therefore of flat and rectangular shape, having a width of about 1 mm and a length of about 1.5 mm. When we observe these fibrettes in transvision and UV, they have a green color.
These "tri-colored" fibrils are dispersed in the paper pulp intended to produce a security paper. The sheet is made on a paper machine according to the techniques known to those skilled in the art, with possibly other known security elements.
The resulting security paper comprises several fibrettes as previously described visible under UV light, having under observation in reflected light (under UV) on one side a blue color and on the other side a yellow color, and in transmitted light observation. and always under UV a green color. If necessary, apply a slightly opacifying layer before the blue prints so that the blue and yellow prints interpenetrate into reflected light and produce the green combinatorial color that would be observed through.

As a variant, it is possible, in another manufacture, to produce, in addition, single-color fibrettes comprising on one of these faces a blue fluorescent color. Similarly, in another manufacture, one can achieve other fibrettes having on one of these faces, a yellow fluorescent color. A security paper can be made with blue fluorescent fibrettes, yellow fluorescent fibrettes and "tricolor" fibrettes.

As a second example, will be described below the embodiment of another security element according to the invention and a security paper containing it.
A paper of the opacified overlay type, having an opacity such that the patterns that it will be visible are produced without interfering when viewed in reflected (flat) light, but will allow transmitted light observation of the patterns on the front and back. back.
The face is printed by heliography in a fluorescent yellow color. On the reverse side, patterns are printed in the form of a black dot. about 0.2 mm in diameter. The points are printed (distributed) according to the shape and size that will have the board after cutting.
A wetting improving agent and a heat-sealing varnish are applied on the surface to facilitate their holding in the substrate which will contain them.
The sheet is cut into circular boards of 1.5 mm diameter per mark at the points to obtain each board centered on a point.
As in the first example, the circular boards are introduced into paper pulp to make a security paper which will contain them.
When a board is observed in the security paper under UV and in reflection, we see fluorescent yellow boards and boards with the black dot centered on the board. When we observe the paper under UV and in transvision we see a fluorescent yellow board with a black dot centered on the board. In transvision and without UV, we see the boards with the black point centered, a strong light may be necessary for this observation.
Such boards are difficult to imitate by a counterfeiter because it is extremely difficult to print a marked image and further cut also at the marker.

Claims (24)

1. Flat security element in the form of a planchette, with a front face and a back face, characterised by the fact that, printed on each of its faces, it comprises at least one marked authentication pattern and/or an authentication pattern resulting from combining and/or superimposing a pattern on its front face and a pattern on its back face, at least one of said authentication patterns being at least partly observable in transmitted light.
2. Security element according to claim 1, characterised by the fact that said marked authentication pattern is marked either in relation to at least a part of the form of said security element or in relation to at least a part of said patterns.
3. Security element according to one of claims 1 to 2, characterised by the fact that one of the patterns on the front face and/or on the back face is a marked pattern.
4. Security element according to one of claims 1 to 3, characterised by the fact that said element comprises at least a given colour as the pattern on the front and at least another given colour as the pattern on the back, said authentication pattern observed in transmitted light being the colour resulting from the colour of the front and the colour of the back.
5. Security element according to previous claim 4, characterised by the fact that the colours of the front and of the back are selected from primary colours.
6. Security element according to one of claims 1 to 5, characterised by the fact that one of said patterns is a pattern in the form of a geometric pattern, particularly in alphanumeric form and/or in the form of thread and/or lines and/or dots.
7. Security element according to one of the previous claims, characterised by the fact that the dimensions of said element are between 0.5 and 6 mm, preferably between 1 and 4 mm.
8. Security element according to one of the previous claims, characterised by the fact that it has a geometric form, particularly circular, triangular, oval, square, rectangular, star-shaped, moon-shaped or with curved edges.
9. Security element according to one of the previous claims, characterised by the fact that it comprises printing at a rate of 1 to 10 g/m² per face, preferably between about 2 and 5 g/m² per face as dry weight.
10. Security element according to one of the previous claims, characterised by the fact that said element comprises patterns selected from patterns visible in natural light, visible in UV light, luminescent, particularly fluorescent or phosphorescent, detectable by near or mid infrared radiation, thermochromic, piezochromic, based on DNA markers, optically variable, particularly iridescent or based on liquid crystals or diffraction networks or moiré patterns or holograms, electromagnetic or their combinations.
11. Security element according to claim 10, characterised by the fact that said element comprises, underneath or beside said patterns, printing of an electromagnetic nature, particularly magnetic and particularly continuous tracks or codes in the form of magnetic bits.
12. Security element according to one of the previous claims, characterised by the fact that at least one of the patterns is visible to the naked eye.
13. Security element according to one of the previous claims, characterised by the fact that said element comprises chemical authentication reagents or reagents which reveal a specific event.
14. Security element according to one of the previous claims, characterised by the fact that said security element has a support selected from a fibrous sheet, a plastic film and a complex of said materials.
15. Security element according to claim 14, characterised by the fact that said support has a low weight, particularly between 25 and 40 g/m², and/or a thickness between about 50 and 110 µm.
16. Security element according to one of claims 14 to 15, characterised by the fact that said fibrous sheet of said support is based on natural and/or synthetic fibres.
17. Security element according to claim 16, characterised by the fact that said fibrous sheet is a paper based on low refined cellulose fibres of the overlay type.
18. Security element according to one of claims 14 or 15, characterised by the fact that the plastic film of said element is a polyester film.
19. Security element according to one of claims 14 to 18, characterised by the fact that said element is based on a support opacified in the mass or a support comprising on at least one of said faces, at least partly a layer or printing, which is flat or partial, opacifying or barrier.
20. Security sheet comprising a fibrous substrate including several flat security elements of a relatively small size, such as described in claims 1 to 19.
21. Security sheet according to previous claim 20, characterised by the fact that said security elements are arranged in a strip and/or distributed at random within said substrate.
22. Security document obtained from a sheet according to claims 20 to 21.
23. Method for manufacturing security elements, comprising a marked pattern such as described in claims 1 to 19, comprising the following stages:

    - at least part of said authentication patterns are printed in one or several stages on one of the faces of a support with a certain transparency,

    - at least part of said authentication patterns are printed on the other face, in one or several stages, either by marking in relation to at least a part of the form of said element or by marking the part printed previously.
24. Production method according to claim 23, characterised by the fact that the printed support is cut at the marking into security elements according to the desired form and such that at least the marked pattern is present on said element in its entirety.