CA2720661A1 - Method for producing a sheet with a thick or thin section at the level of a ribbon and corresponding sheet - Google Patents

Abstract

The present invention relates to a process for the papermaking of a sheet (1) comprising at least one jet of a fibrous substrate (2) and at least one fibrous tape (3), in which the tape (3) is introduced. in a fibrous suspension of a round-shaped paper machine for forming the jet or in direct contact with the former or in contact with the formed jet, the point of introduction of the ribbon (3) being chosen so as to create at least one a sub-thickness or an extra thickness on the sheet (1) at the ribbon (3), the under-thickness being due to a reduction of the dripping of the fibrous suspension by the ribbon (3).

Description

A process for producing a sheet having a sub-thickness or an over-thickness thickness at Ribbon level and associated sheet The present invention relates to the field of security documents and inter alia a method of manufacturing a security sheet, for example example mostly paper.
In the description, paper means any sheet obtained wet at using a suspension of natural cellulose fibers and / or fibers mineral, vegetable organic substances other than cellulose, which may be synthetic, contain various fillers and additives commonly used in stationery.
Background During the production of security documents, including security, it is common to want to incorporate one or more elements of security, by example by applying a film or security thread on a sheet of security or by the coating of an iridescent sleeping belt or even by the creation of windows in a security sheet and applying a transparent film at the level from these windows.
It generally results in the creation of extra thicknesses on the documents of security that can for example generate problems of flatness of security documents or good still make difficult the printing steps.
Several solutions have been proposed with the aim of reducing local the thickness of a security sheet where security features have to be placed, when making the sheet on the round shape of a machine paper. In In most cases, the proposed solution is to seal off part of the canvas training used during the manufacturing process of the safety sheet on round form.
International Application WO 99/06629 describes a manufacturing process of a sheet using a flat-table paper machine equipped with a cloth textile to obtain areas of low and heavy weight.
International application WO 93/00474 also describes a method of making a security sheet using a table-top machine flat equipped a canvas on which have been added pellets reducing dripping and allowing thus forming areas of different weights.

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2 PCT / FR2009 / 050594 European Patent Application EP 0 625 431 describes a manufacturing process a security paper with a security thread made from a film and incorporated between two jets.
European Patent Application EP 0 549 384 describes a manufacturing process paper with areas of reduced thickness obtained from the solidarity of pellets to the formation web of the round form.
European Patent Application EP 1 122 360 describes a manufacturing process a paper in which a watermark is made from modifications made on the canvas of formation of the round form.
British Patent Application GB 2 433 469 describes the manufacture of a fibrous safety substrate in which fibrous tape is incorporated with a plurality of openings.
European Patent Application EP 0 070 172 describes a manufacturing process a security paper with ribbon with alternating zones allowing the deposition of paper fibers and areas preventing the deposition of fibers paper mills.
European Patent Application EP 0 773 320 describes the insertion of a strip between two paper jets, one of which has a watermark.
British Patent Application GB 2,395,724 describes the incorporation of a polyester strip comprising an electronic chip in a fibrous substrate.
The solutions proposed by the prior art do not make it possible to carry out areas of reduced thickness on a security document with a process relatively simple.
Indeed, the proposed solutions require modifications and a preparation important training cloths used on round shapes and allow generally not to obtain reduced thicknesses of sufficient dimensions for the incorporation of the security elements presented above.
summary There is therefore a need to remedy at least some of the disadvantages mentioned above.
In particular, there is a need to improve the production of security, in particular safety sheets, in particular for carrying out areas of varying thickness on the documents.

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3 PCT / FR2009 / 050594 The invention aims to meet all or part of these needs, by incorporating a ribbon, fibrous or not, to the safety sheets during their manufacture, this tape that can advantageously be located at or near a place where to be applied security elements.
The object of the invention is therefore, according to one of its aspects, a method of papermaking of a sheet having at least one jet of a substratum fiber and at least one fibrous ribbon, wherein the ribbon is introduced into a fibrous suspension of a round-shaped paper machine allowing the jet formation or is introduced in direct contact with the round shape or in contact with the jet formed, in particular before the jet leaves the lifting cylinder.
The point of introduction of the ribbon may be chosen so as to create at least a sub-thickness or over-thickness on the sheet at the ribbon level, by example when it emerges from the fibrous suspension or after, the under-thickness being due to a reducing the draining of the fibrous suspension by the ribbon.
Thanks to the invention, it is possible to obtain a security sheet with at least one under-thickness or over-thickness that can allow incorporation security features without requiring the use of a training canvas specific or modified, in particular because of the use of a fibrous tape incorporated in the substratum fibrous when making the safety sheet. Because of this, it is possible to use the training webs that usually equip paper-forming machines round used for the manufacture of safety sheets.
In addition, the use of a ribbon of varying width and / or thickness example, can make it possible to obtain under-thicknesses or over-thicknesses of dimensions variables too.
The one or more under-thicknesses or over-thicknesses created can extend all the along the leaf.
The jet carrying the ribbon may not come in partial recovery of the ribbon, i.e., the fibrous substrate does not cover the lateral portions of the ribbon on his main faces on either side of these over a width substantial, for example greater than or equal to 1 mm.
Thanks to the invention, it is possible to incorporate one or more elements of security of all types in the security sheet nearby or at the sub-WO 2009/136059

4 PCT / FR2009 / 050594 thicknesses or thicknesses without generating locally, for example, over-thicknesses related to the presence of the security element or elements. A sub thickness can by example, to incorporate at least one element of security of which the thickness can be offset, at least partially, by the thickness. An over-thickness can for example allow to juxtapose the ribbon at least one element of the thickness of which can be offset, at least partially, by the extra thickness.
The invention can also make it possible to produce new structures of safety, irrespective of the possible thickness compensations discussed above.
The ribbon can be introduced into the fibrous suspension or direct contact of the round shape, in various ways.
By direct contact, we mean that the point of introduction of the ribbon is at contact of the round shape while it is not covered with fibers of suspension fibrous at the point of introduction of the ribbon. The introduction point can especially to be done on an area of the round shape not immersed in the fibrous suspension. Of preference, the cohesion of the formed sheet can be, in this case, provided by a second throw fibrous, which can be attached to the first stream formed and in particular on the face in contact with the training canvas during his training (face canvas).
The fibrous tape can be introduced in direct contact with the round shape, by one of its faces, before entering the fibrous suspension. Of this way, none fibrous suspension fiber can not be deposited on the face of the ribbon contact of the round shape. It is thus possible to obtain a jet of paper on one of the faces of which is visible the face of the ribbon that has been in contact with the round shape. In this case, a sub-thickness can be made at the other side of the ribbon, opposite to the round shape.
The ribbon can still be introduced into the fibrous suspension while fibers have already deposited on the round shape at the point of introduction of the ribbon. Fibers may have already been deposited on the entire round shape on the surface of the round shape or partially on the surface of the round shape. In this way, it can be possible no face of the ribbon is in direct contact with the web of the form round. Tape On the contrary, it can be in contact, by one of its faces, with the fibers have already been on the round shape before the introduction of the ribbon into the fibrous suspension.
So, the face ribbon in contact with the fibers already deposited on the round shape may not be to be observable on the safety sheet after manufacture. In this case, a sub-thickness or WO 2009/136059

5 PCT / FR2009 / 050594 over-thickness with respect to the thickness of the vellum, that is to say to the thickness from the area of sheet, in particular of the substrate, where the ribbon does not appear, can be achieved at the level of the other side of the ribbon, opposite to the round shape.
The face of the ribbon that is in direct contact with the round shape or fibers of the Fibrous suspension that have already deposited on the round shape, can butcher the holes of the training web of the round shape and can thus prevent the suction against the canvas fibers of the fibrous suspension.
The ribbon can be fed into a twin-jet paper machine. In this case paper machine may comprise for example two round shapes placed in line, a round shape and a flat table, or else a round shape and a cylinder former (short train). In particular, the paper jet formed on the round shape and having the ribbon can be joined in wet part of the paper machine with a second jet of paper overlapping the ribbon. The second jet can then consolidate the first throw of paper in the ribbon introduction area. It can also constitute a protection for elements present in or on the ribbon, for example a device electronic system, in particular an integrated microcircuit device, for example a device RFID.
It is still possible to use a paper machine equipped with a single form round.
The introduction of the ribbon can be done by a feeding device, by example such as a peeling system, placed along the width and leading into the shape tank near the round shape, before the start of the draining of the Fibrous suspension on the canvas of the round form. After draining, we gets the sheet of security which can then be pressed and dried according to the paper process current.
The jet obtained can optionally be married in the wet state, that is to say before drying, with other jets whose fibrous compositions can be identical or different and that can be trained on table-top machines flat, with cylinder form or round form.
The jet obtained can be joined by laminating with another jet of paper coming over the ribbon.
The sheet may consist of two jets of paper each having a ribbon and one or both of which has at least one sub-thickness or extra thickness WO 2009/136059

6 PCT / FR2009 / 050594 at the ribbon level. The two ribbons of the two jets may or may not be contact one of the other, after assembling the jets.
Advantageously, the introduction of the ribbon can be carried out in the direction of the of the leaf and thus allow easy introduction of elements of security, typically entering in the same direction during a process of manufacture of a security sheet.
The ribbon may have at least one of its faces not completely covered fibers from the fibrous suspension at the exit of the paper machine to round shape.
The creation of a sub-thickness or an over-thickness can result from a fiber deposition of the partial or no fibrous suspension on at least one faces of the ribbon. In particular, it may depend on the angle of introduction of the ribbon, the thickness of this one, of a coating present on its surface and / or of a relief present on the round shape.
The ribbon may have a thickness greater or less than the thickness of the vellum of the security sheet.
When the ribbon is less than the thickness of the vellum of the leaf where the ribbon is, the sheet may have a sub-thickness at the ribbon, especially on the face of the ribbon opposite to the round shape, in especially when the ribbon is introduced in direct contact with the round shape or when the ribbon is introduced in the fibrous suspension while the thickness of the fibers already present on Form round is less than the difference in thickness between the vellum thickness of the leaf and the thickness of the ribbon.
Alternatively, the sheet may have an over-thickness at the ribbon, by example while the ribbon is introduced into the fibrous suspension while thickness fibers already present on the round shape is greater than the difference thick between the thickness of the vellum and the thickness of the ribbon.
When the ribbon is thicker than the thickness of the vellum of the leaf, the sheet may have an excess thickness in the ribbon, particularly in the level of opposite side of the ribbon to the round shape.
As mentioned above, the deposition of the fibers on one of the faces of the ribbon, the opposite face to the round shape, may be zero because the presence of the ribbon against the round-shaped fabric prevents drainage, that is, the deposit of fibers of the fibrous suspension against the web.

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7 PCT / FR2009 / 050594 The deposition of the fibers on one of the faces of the ribbon, in particular the face opposite to the round shape, may still be only partial, especially because the ribbon may have previously treated, for example by a coating, to reduce its porosity, and prevent or slow down the deposition of fibers on the treated area. The treated area can by example correspond to a central area on the ribbon, especially on the face opposed to the round shape.
For example, the treatment of the area may result from the application of a coating such as a composition comprising a hydrophobic compound and / or mouth-porating. This application may for example consist of the coating of a latex or a hydrophobic varnish.
The round shape can be devoid of relief on which is placed the ribbon or alternatively to include. Where appropriate, the relief may be formed by embossing the fabric of manufacture. For example, the ribbon can be introduced so that his center coincides with the center of the relief of the round form.
The relief of the round shape may, for example, have in front view a shape square, round, oval, polygonal, with rectilinear contours or curvilinear, being rectangular preference. The relief can be continuous or discontinuous along the circumference of the round form. The ribbon may be wider than that of relief. In this way, for example, it is possible to have at least some ribbon, especially the two edges of the ribbon, which is not superimposed on the relief.
The ribbon can be introduced while fibers from the fibrous suspension are already deposited on the relief of the round form. In this way, the ribbon can not to be directly in contact with the relief of the round shape, one of its faces being in contact with fibers already deposited on the round shape.
Alternatively, the ribbon can be introduced while no fiber from the suspension fibrous material was deposited on the relief of the round shape, in particular introductory ribbon. In this way, one of the faces of the ribbon can be directly in contact relief of the round shape, this face can be visible on the security sheet after its manufacture.
When the round shape has a relief and the ribbon is wider than the relief, fibers of the fibrous suspension can be deposited between the parts of Ribbon not superimposed on relief and round shape. In this way, it can be possible to create one or more under-thicknesses on the sheet at the face of the ribbon who is in WO 2009/136059

8 PCT / FR2009 / 050594 look at the round shape. In this case, it may also be possible to create one or several under-thicknesses or over-thicknesses at the level of the face of the ribbon opposed to the round shape, particularly depending on the thickness of the ribbon compared to the thickness of the vellum of the leaf.
The presence of one or more under-thicknesses or over-thicknesses can at least partially accommodate one or more elements of security, respectively superimposed at the level thereof or juxtaposed therewith. In particular, the security element or elements can be arranged between two over-thicknesses which ensure thus their mechanical protection, for example against shocks, impressions as impressions by intaglio, or during subsequent pressing or lamination.
When the thickness of the security elements is substantially identical to the difference between the thickness of the vellum of the leaf and that of the ribbon, it is possible to obtain a security sheet having substantially no under-thickness or extra thickness.
In particular, the security sheet may comprise at least one element of safety superimposed on the ribbon on the side of the under-thickness and having a thickness at least partially compensated by the under-thickness. The sub-thickness can totally compensate for the thickness of the security element.
In particular still, the security sheet may comprise at least one security element juxtaposed with the ribbon whose thickness is at least partially compensated by the over-thickness. The over-thickness can totally compensate the thickness of the security element.
Over-thicknesses can allow for example to obtain effects safety precautions following a treatment of the fibrous tape, for example embossing, at the level of the over-thickness.
The ribbon treatment at the level of the super-thicknesses can make it possible to obtain a security sheet having substantially no under-thickness or extra thickness.
The ribbon may for example undergo an embossing, including embossing to hot, especially at an over-thickness. In this case, the ribbon can preference have polyethylene fibers. The introduction of a ribbon with fibers of polyethylene allows in particular the subsequent creation of particular reliefs by embossing while giving the leaf a better cohesion because the cohesion a substrate WO 2009/136059

9 PCT / FR2009 / 050594 cellulosic, for example, is indeed superior to that of a substrate composed of fibers of polyethylene.
The ribbon may have an over-thickness, especially before embossing ribbon, extending over at least 50%, better 80% or more, of the surface of the ribbon face where the over-thickness is. The over-thickness can extend on the totality one side of the ribbon.
After embossing, the sheet may be free of over-thickness. The surface of the ribbon face that had the over-thickness before embossing may be substantially flat.
The ribbon may have micro-reliefs, for example recesses or projections, especially after embossing, of reduced dimensions, for example of dimension ranging from 1 at 3 m. These micro-reliefs do not form over-thickness or under-thickness at direction of the invention.
The under-thickness or over-thickness can make it possible to obtain respectively a embossed or protruding relief on the security sheet, of the order of several micrometers.
In this case, the values of the under-thicknesses or the over-thicknesses may to be determined according to the thickness of the security elements intended to be associates. By for example, a printing or security film arranged in a sub-section thickness or between two over-thicknesses. The aim may be, in particular, to obtain of a leaf formed flat, that is to say without sub-thickness or over-thickness.
The under thicknesses obtained may for example be values greater than or equal to 15 m, preferably 30 m, more preferably 60 m. By For example, it is possible to obtain sub-thicknesses greater than or equal to 44 m for a substrate with a thickness greater than or equal to 115 m.
The extra thicknesses may be a function of the point of introduction of the ribbon and of its thickness. For reasons of machinability, it may be advantageous to limit to over-thickness less than 20 m although the protection of certain elements of security may require larger thicknesses.
The ribbon can still be introduced by bringing the ribbon into contact from the papermaker jet present on the fabric of the round shape at the exit of the tank of form. The ribbon is for example inserted between the jet coming out of the form tank and a second throw which is assembled at the first between the lifting cylinder and the round shape.

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10 PCT / FR2009 / 050594 Ribbon The term ribbon refers to a ribbon made in one piece or made of a assembling, stacking or juxtaposing strips or parts elementary.
Advantageously, the fibrous ribbon is a paper ribbon. The introduction of a paper tape, compared to the introduction of a plastic tape for example, can to permit to obtain a sheet having good cohesion due to the bonds which can develop between the paper ribbon and the substrate. In particular, when second throw is applied on the ribbon, the fact that the ribbon is made of paper, and not plastic for example, can ensure a significant cohesion between the ribbon and the second jet.
The ribbon may be fibrous and have non-fibrous elements.
The ribbon may have a basis weight of between 5 and 100 g / m 2, preferably between 15 and 55 g / m 2 and more preferably between 20 and 30 g / m2.
The ribbon may have a width of between 2 and 60 mm, preferably between 4 and 30 mm and more preferably between 10 and 20 mm.
The ribbon may have a width greater than the relief of the shape round, where appropriate.
The ribbon may have a thickness greater than 10 m, preferably between 20 and 120 m, and more preferably between 30 and 80 m.
The ribbon may have a thickness different from that of the vellum of the leaf.
By For example, the ribbon may have a thickness greater than that of the vellum of the sheet for allow the creation of super-thicknesses. The ribbon can still have a lower thickness to that of the vellum of the sheet to allow the creation of sub-thicknesses.
The ribbon may further comprise at least one electronic device, in particular an integrated microcircuit device. The electronic device maybe a detector. The electronic device can be an identification device by frequencies radio, more commonly called RFID device, and in particular a chip electronic and / or an antenna which may in particular be printed on the ribbon. The device electronics can for example be deposited and fixed, for example by gluing, on one of ribbon faces. The electronic device can still be incorporated into inside the ribbon, especially before its introduction near the round shape, in contact direct from the round shape or in the fibrous suspension.

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11 PCT / FR2009 / 050594 The ribbon may be made from a material, including a paper, having has previously undergone a wet strength treatment (WER).
The ribbon may have wet strength (WER) relative to the traction greater than 30%, especially in order not to cause any problems during introducing the ribbon into the sheet. Resistance in the wet state traction is measured by dividing the value of the wet tensile strength measured according to the NF Q standard 03.056 by the dry tensile strength measured according to the NF EN ISO standard 1924. This resistance in the wet state can in particular be provided conventional by the addition of a wet strength agent, for example such as a polyamine resin amide-epichlorohydrin (PAAE), a formaldehyde melamine resin, etc.

Alternatively, an additional wet strength (REH) may be obtained by adding a portion of the REH agent (s) to baths of surfacing a fibrous sheet, for example for the manufacture of the ribbon.
Security features that can be incorporated into the ribbon or Ribbon proximity can be of different types.
Security elements can represent different patterns, for example a or several alphanumeric characters or drawings or logos, for example present by elsewhere on the sheet.
The sheet may have at least two under-thicknesses or two over-thicknesses or a sub-thickness and an over-thickness facing one another and at less two security features can be incorporated at or near each of these under-thickness or over-thickness, the security elements being able to be look at one of the other.
The two security elements can be applied, for example by impression, at the mark. By printing at the mark, we mean that the position elements security on the ribbon is determined.
The two security elements of the ribbon can make it possible to obtain different effects, in particular optical, thanks to their observable complementarity transvision.
By observable in transvision, we mean an observation of the light that crosses the ribbon in the direction of its thickness, for example in light visible, ultraviolet or infrared.

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12 PCT / FR2009 / 050594 The two security elements can for example make it possible to obtain in transvision a moiré effect.
A moire effect can for example reveal a pattern produced by the superposition of the two security elements, for example by reconciliation lines two security elements. For example, a first impression can be performed on the front side of the ribbon and a second impression can be made on the reverse side of ribbon. Impressions can be made at or near sub-layers or over-thickness. So during the observation in ribbon transvision, a pattern complementary may appear by moiré effect between the first and second impressions.
The two security elements can still allow for example to obtain in transvision of combinatorial effects.
A combinatorial effect results from the observation in transvision of a motive which is the result of the combination of two each on the front and the back of the ribbon. For example, a first pattern can be printed on the front ribbon and a second pattern can be printed on the back of the ribbon. During the observation in transvision, a third reason may then be observed, resulting from the combination of first and second reasons.
The security elements can be prints, including inks.
Inks may have other additional security features, like the specific pigments.
Security features can still be movies, for example movies plastics, transparent or not, or having a reduced opacity, for example lower or equal to 40%, preferably less than or equal to 30%, measured according to the the ISO's norm 2469.
The ribbon, whether fibrous or not, may comprise one or more openings, by example made partially or totally in the ribbon.
The openings may be of various shapes, for example of square shape, oval, round, rectangular, polygonal, star, among others. The openings can correspond to holes, slots, drawings, through cavities or no, by examples made by embossing, cutouts according to patterns alphanumeric, shapes and sizes. The openings can be through. The openings can WO 2009/136059

13 PCT / FR2009 / 050594 be made after forming the safety sheet. Alternatively, the openings can be made on the ribbon before its introduction.
The openings may include one or more security features, including an electronic device, in particular an integrated microcircuit device, for example a RFID device.
Where appropriate, the security features may extend completely or partially in the openings.
Security features, including movies, can be placed at the or in the vicinity of under-thicknesses or over-thicknesses, in particular sub-layers thicknesses or over-thickness compared to each other. In particular, the elements of security can be juxtaposed on both sides of the over-thickness, or be superimposed on the sub-thicknesses, the security elements being opposite each other.
Under-thicknesses and / or over-thicknesses can in this case compensate for less partially the thickness of the security elements.
Security features, including movies, can be superimposed on under-thickness at the level of openings made in the ribbon.
At least two security features, including movies, can be superimposed on at least two sub-layers facing each other, at least an ajour being made in the ribbon at the two sub-thicknesses.
The sheet may in particular comprise on each side of the ribbon thickness in which at least partially at least one element of security, in particular a film extending parallel to the tape on contact. An element of security, including a film, may extend at least partially each of the sub-thicknesses of the leaf.
The security elements, in particular films, can be complementary, that is to say that during the observation in transvision of the two elements, is possible to obtain different optical effects, for example moire effects and / or combinatorial, for example the appearance of a pattern resulting from the superposition of patterns present on two security elements.
The security elements may for example have sufficient opacity to allow the observation of particular optical effects in transvision.

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14 PCT / FR2009 / 050594 Security features, including films, may be introduced at near the round shape during the formation of the leaf.
The thickness of the films is, for example, greater than or equal to 10 m, preferably greater than or equal to 30 m.
The thickness of the films may be at least partially compensated for by thicknesses or over-thicknesses. For example, the cumulative thickness of a film and ribbon can to be equal to the thickness of the vellum of the sheet within plus or minus 5 m, better more or less than 3 m. This is an advantageous embodiment of the invention which allows for a substantially flat sheet, thus reducing the problems due to differences in thickness and occurring during any eventual later stages:
for example unwinding, winding and cutting the sheet, stacking and the printing of leaves.
The films may include a specific material that collects light.
Such luminescent light collecting materials that may be suitable are called waveguide. These are, for example, polymer films based on polycarbonate, called LISA and marketed by the company BAYER.
The films can be inks, varnishes, resins, strips cut, laminated, especially hot rolled, or extruded.
The films can be colored, including having different colors.
The ribbon may comprise at least one security thread, in particular a thread of security device on which an electronic device, in particular a device with microcircuit integrated, for example an RFID device.
An electronic device, in particular an integrated microcircuit device, by example an RFID device, may be at least partially housed in a reduced thickness, the sub-thickness at least partially compensating for the thickness of the device electronic.
The ribbon may be perforated and substrate fibers may be included in the ribbon perforations. In particular, the substrate fibers appearing in the perforations of the Ribbon can be of different color than the ribbon.
The ribbon and / or the substrate may have several characteristics particulars mentioned below. These features may apply to all ribbon and / or substrate or only part of the ribbon and / or substrate, and more WO 2009/136059

15 PCT / FR2009 / 050594 preferentially to one or more parts of the ribbon and / or substrate where one or several sub-thicknesses or over-thicknesses.
The ribbon can for example be combined with a strip of material thermoplastic and / or metal, for example PET, laminated or laminated hot on ribbon before its introduction near the round shape.
The ribbon and / or the substrate may be devoid of watermark.
Alternatively, the ribbon and / or the substrate may comprise at least one watermark.
The ribbon watermark may be at a sub-thickness or above thickness of the security sheet.
When the ribbon and the substrate have a watermark, the superposition of the watermark of the substrate and the watermark of the ribbon may allow to observe a pattern resulting from their association.
The watermark of the ribbon can also be juxtaposed with the watermark of the substrate to that this juxtaposition creates a new motive.
The eventual watermark of the ribbon and / or substrate may be a clear watermark.
In this case, the light areas of the watermark have a density strictly less than vellum. Alternatively, the watermark may be a watermark dark. The watermark may still be a multiton effect watermark set of areas made to form a halftone image with clear tones and dark. This The halftone image may comprise raster patterns formed for example by lines. The Patent Application EP 1 122 360 discloses the production of such a watermark.
The possible watermarks of the ribbon and the substrate can also be superimposed to get a moire effect.
The ribbon may have optical properties different from those of substrate, especially at a sub-thickness and / or an over-thickness, especially staining, fluorescence, phosphorescence, magneto-optical, photochromic, thermochromic, piezochromic, iridescent, among others.
For example, the substrate and the ribbon may have different colors.
All colors are possible. Ribbon and substrate can present a difference of color or color difference AE (according to the CIE Lab color space 1976) greater than 0.2 and preferably greater than 1. However, the human eye is more sensitive WO 2009/136059

16 PCT / FR2009 / 050594 to a color difference on unsaturated hues, and those skilled in the art can adapt the difference in color so as to obtain the desired contrast.
The ribbon may comprise a conventional or security ink, in particular fluorescent, phosphorescent, magnetic, photochromic, thermochromic, piezochromic, iridescent, transparent, among others. The ink can be applied partially or totally on the ribbon, that is to say only on certain areas of the ribbon surface or on the entire surface of the ribbon. The ink can be applied on the ribbon by a printing medium such as offset, rotogravure, screen printing or inkjet printing.
One or more security elements that can be selected from among the inks previously mentioned and can be applied at the level of the under-thickness or juxtaposed to the over-thickness.
The ribbon can still be coated with a clear or colored varnish.
The ribbon may include a fluorescent agent. The fluorescent agent can be colored or not, visible or invisible in visible light. The fluorescent agent can for example be incorporated in the mass of the ribbon. The fluorescent agent can be visible for example under ultraviolet (UV) and / or infrared (IR) light.
Preferably, the ribbon may extend between two opposite edges of the sheet.
The ribbon may have irregularly shaped edges, for example having the broken or wavy lines, crenellations, zigzag, among others. The edges of ribbon can have the same shapes or different shapes, regular or irregular.
The ribbon may still have different characteristics perceptible by example to the sight or the touch.
The ribbon can for example be embossed, thus creating an effect particular, for example a touch effect or surface relief. This effect can allow the formation of micro-reliefs on the ribbon, distinct from under-thickness or over-thicknesses.
The ribbon may be coated with a thermoplastic polymer and then optionally embossed as a result of this coating.
The ribbon can be printed with drops of varnish, resin or ink thermo-inflating, among others.
When the ribbon has impressions, this can for example allow to obtain variable optical effects.

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17 PCT / FR2009 / 050594 The ribbon may include a heat-reflecting ink for creating minus a relief, this ink being activated before introduction of the ribbon.
Activation before incorporation reduces the risk of destructuring the sheet during swelling ink.
The ribbon may comprise particles, for example detectable with the naked eye or to the touch, introduced en masse into the ribbon, for example in the form of balls by example of the balls of a synthetic material, for example polyurethane, or mineral, for example glass, of dimension for example less than 300 m, or by deposit by screen printing or gravure printing, for example in the form of beads, for example dimension less than 100 m.
The ribbon may comprise a textile band, for example knitted, integrated into the ribbon or laminated to the ribbon. The ribbon may comprise textile fibers.
The ribbon can be made of a woven or a non-woven.
The ribbon may comprise an embossed printing, for example screen-printed.
The ribbon may have a touch of fat, rough, smooth, silky, sweet, among others.
The ribbon may in particular comprise polymer deposits, in particular under beads, for example polyurethane (PU) beads, glass, polyamides 6 or 12, styrene-acrylic pigments, waxes or polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), polymers with base of methyl methacrylate.
The ribbon can advantageously retain its own cohesion after introduction into the fibrous substrate. Also, the ribbon structure can be observable after its introduction into the fibrous substrate under certain conditions, by example in cutting or by vision in reflection or transmission. So, it can be possible to observe ribbon due to differences in optical properties, for example contrast differences, of hue, saturation, clarity, opacity, which make visible a border between the ribbon and the substrate or characterize the presence of the ribbon.
The ribbon may still be observable by topography in the leaf.
The ribbon can also, if necessary, be observable by transparency in the leaf, especially with the naked eye.

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18 PCT / FR2009 / 050594 In order to obtain the ribbon, it is possible for example to manufacture a fibrous sheet, of preferably of low grammage, for example between about 15 and 90 g / m 2, depending on a method papermaker, that is to say for example by draining a suspension of fibers optionally comprising conventional fillers and additives in paper industry, of the possible specific safety elements, pressing of the resulting fibrous mat then drying. This sheet is then optionally calendered which allows particular of reduce its thickness, then cut it to form ribbons which are then wound in coils.
The ribbon may comprise cellulosic fibers (in particular cotton) and / or natural organic fibers other than cellulosic and / or fibers synthetic materials, for example such as polyester or polyamide fibers, and or optionally mineral fibers, for example such as glass. Tape may not include polyvinyl alcohol (PVA) fibers.
The fibers may be hydrophilic, in particular so as to develop chemical bonds, mainly hydrogen, with the fibrous substrate.
The ribbon may comprise in dry weight at least 50% of cellulosic fibers.
The ribbon may comprise perforations, in particular in order to favor dripping during the production of the sheet or adding an effect optical additional, especially in combination with at least one watermark. By example, these perforations are arranged at the edge of said ribbon or so as to form a pattern or a code.
The ribbon may have a watermark and perforations around it watermark.
The ribbon may have at least one security element on one of its faces, even on each of its faces. The ribbon may include elements of security different on each side.
The ribbon may comprise one or more security elements superimposed on the ribbon in a sub-thickness or juxtaposed to an over-thickness of the ribbon, and / or security elements incorporated in the ribbon or placed on the ribbon independently sub-thicknesses or over-thicknesses. These security features may be such described above after.
Some of the security features are detectable to the naked eye, light visible, without the use of a particular device. These security elements include by WO 2009/136059

19 PCT / FR2009 / 050594 for example a watermark, colored fibers or boards, printed threads, metallized or holographic, holographic foils or optical impressions variable.
These security elements are called first level.
Other types of security elements are detectable only by means of a relatively simple device such as a lamp emitting in the ultraviolet or infrared.
These security elements comprise, for example, fibers, boards, tapes, wires or particles. These security features may be visible at the naked eye or not, being for example luminescent under a lighting of a Wood emitting lamp in wavelength of 365 nm.
These security elements are said to be second level.
Other types of security elements still require for their detection a more sophisticated detection device. These security features are able example to generate a specific signal when submitted, simultaneously or not, at a or several external sources of excitation. Automatic detection of signal allows to authenticate, if necessary, the document.
These security elements comprise, for example, tracers presenting themselves in the form of active ingredient, particles or fibers, capable of generate a signal specific when these tracers are subjected to optronic excitation, electric, magnetic or electromagnetic.
These security elements are said to be third level.
The security elements carried by the ribbon, whether fibrous or not, can be first, second or third level.
The security elements may in particular be chosen from the tracers, particularly nanometric, especially metallic security fibers, magnetic soft and / or hard magnetism), or absorbing or excitable in the ultraviolet (UV), the visible or infrared (IR) and in particular the near infrared (NIR), elements of flat and relatively small format such as small boards, pigments or agglomerates of pigments especially absorbent or excitable under illumination Laser or in the ultraviolet (UV), visible or infrared (IR), particularly the near infrared (NIR), and security threads (plastic-based, especially polyester) comprising in particular at least a partial coating, metallic, metallized, iridescent or magnetic (with mild and / or hard magnetism), the coating possibly including reasons in WO 2009/136059

20 PCT / FR2009 / 050594 positive or negative, and the said grounds may in particular be obtained by demetallization chemical or biochemical reagents for tampering and / or authentication and / or identification may in particular react with at least one agent respectively falsification and / or authentication and / or identification, and the elements optically variables including holograms, liquid crystals, pigments iridescent or mirror-effect structures, in particular dielectric structures, and their combinations.
The ribbon may have a series of parallel safety wires, and more particularly the succession of inter-son spaces and / or the series of different widths security threads constitute a code, in particular of the barcode type.
The ribbon may still include a soft magnetically anti-theft wire.
The ribbon may further comprise at least one chemical or biochemical reagent of infalsification and / or authentication and / or identification reacting so colored, at least one agent respectively falsification and / or authentication and / or Identification.
The ribbon may have perforations in a pattern or code. In function of the differences in opacity and color between the substrate and the ribbon, the pattern or code is observable, or observable only in transmitted light or observable at a time in transmitted light and reflected light. If the ribbon has a invisible printing fluorescent, the pattern can also be visible only under UV illumination.
In particular, the pattern produced by perforation may comprise at least one alphanumeric character or ideogram.
When the ribbon has at least one ajour, this ajour can come overlap at least partially with a corresponding opening made in a second paper jet attached to the first jet in which is incorporated the ribbon.
The opening of the ribbon corresponds for example exactly to the opening of the second jet. At least one element of security can be superimposed on the ajour, this security element being example housed in a sub-thickness created in the first jet of paper by the ribbon. The presence of the ajour in the second jet can for example allow to observe the inner face of the element security, turned to the ribbon. The latter may be fibrous or not.
The invention can make it possible to produce a security sheet comprising two jets of paper, each with a ribbon to create a sub-thickness. These two jets of paper can be gathered in such a way that the ribbons superimpose WO 2009/136059

21 PCT / FR2009 / 050594 less partially, better substantially exactly. Each sub-thickness can accommodate a security element. The ribbons may each include least one area reduced opacity, for example defined by an aperture, and the two elements of security arranged on either side of the set of ribbons can be observed in transvision through areas of reduced opacity ribbons. This can allow by example the observation of complementary reasons. Ribbons can be fibrous or no.
The invention can make it possible to produce a security sheet by bringing together two jets papermakers each provided with a ribbon defining a sub-thickness. Both jets can be joined by the faces presenting the under-thicknesses, and these sub-layers thicknesses can accommodate a third ribbon introduced between the jets. This third ribbon so between the ribbons incorporated within each of the jets.
The invention can still make it possible to produce a security sheet having two ribbons arranged so as to provide a space between them, these ribbons forming extra thicknesses on one face of the sheet, with respect to the substrate fibrous, a safety element being disposed between the projecting portions of the ribbons. The presence of ribbons protects the security element against a risk crushing by example.
The tape may be free of a surface coating, especially free a pigmented layer. The good affinity between the fibrous substrate and the ribbon is so favored.
The ribbon may have wet strength (WER) relative to the traction greater than 30%, especially in order not to cause any problems during its introduction into the sheet.
The ribbon may comprise an adhesive, for example a heat-sealing agent, so that to improve its cohesion within the fibrous substrate.
When the tape has an adhesive, the latter makes it possible to optimize the adhesion of the ribbon in the sheet.
The adhesive may for example be a heat-sealing coating, for example a heat-sealing varnish, an ultraviolet (UV) crosslinker, an adhesive to irradiate, a pressure-sensitive adhesive (PSA), a varnish with a solvent base, of the type polyester by for example, an adhesive in the aqueous phase, etc.

WO 2009/136059

22 PCT / FR2009 / 050594 As adhesive in the aqueous phase, mention may especially be made of following: Mowilith DC (aqueous dispersion of vinyl acetate homopolymer with particles ranging in size from 0.3 m to 2 m and glass transition T.
about 38 C, and dry solids content between 55 and 57%) and the Vinamul 3265 of the company CELANESE; DH9004, DH9017, DH9044 and DL5001 from the COLLANO company; Primal NW1845, Primal LC40, Primal P308M and Primal EP6000 from Rohm &Haas; the 006SDW078-2 from BASF.
The adhesive may advantageously be an adhesive based on polyvinyl acetate like the Mowilith DC.
The Applicant has found that among the adhesives mentioned above, the Vinamul 3265, Mowilith DC, Collano DL5001, Primal NW1845 and Primal P308M show very good results in the dry crumple test, ie say that adhesion of the ribbon in the paper is not excessively affected by the creasing.
In addition, Vinamul 3265 and Mowilith DC are also very good results in the wet crumple test. The Mowilith DC presents very good results at washing test.
Also, the Mowilith DC provides very good results in terms of power adhesion, but the invention is not limited to a particular adhesive.
According to an exemplary implementation of the invention, the adhesive is not present in fiber form or in particulate form.
The addition of the adhesive to the security tape can in particular be done by a coating process, for example a coating, or by methods derived from techniques printing of a paper base after its manufacture, for example coating to air blade, rotogravure, silkscreen, curtain coating, flexography, between other.
The coating of the adhesive, for example on a fibrous sheet used for ribbon production, can be done for example at a rate of 2 to 15 g / m2 per opposite preferably between 3 and 8 g / m2 per side.
The sealing temperature can vary between 70 and 135 C, for example, according to the adhesive used, and the sealing can take place during the drying of the security sheet.
The coating can be carried out at least partially at the core, that is to say reach in depth, or even in full, the ribbon or on the surface.

WO 2009/136059

23 PCT / FR2009 / 050594 Preferably, the coating is carried out on the support used for manufacture of ribbon before cutting of this support. Alternatively, the coating can be realized during the manufacture of the support for the manufacture of the ribbon.
The coating can be performed on one side of the support or on both faces of the support. The adhesive can completely cover the face on which it is deposited.
The incorporation of the adhesive into the ribbon can also be done by impregnation, by dipping the ribbon or the support used to make it in a bath.
In an exemplary implementation of the invention, a sheet is coated 20 g / m2 fibrous treated with wet strength treatment (REH), with a adhesive in aqueous phase at a rate of 5 g / m 2 per side, using a process by gravure for example. We thus obtain a satisfactory compromise between power adhesion and amount of coated material.
To detect the presence of the adhesive in a security sheet according to the invention, it is possible to observe the adhesive, for example varnish heat sealing, under the shape of bubbles, for example using an electron microscope to scanning (SEM).
substratum The term "substrate" designates a fibrous sheet that may especially be include one or more fibrous layers. In particular, we will use the term jets to denote layers continuously produced on the same paper machine then associated with the wet state.
The substrate may comprise at least one security element as described previously, for example chosen from tracers, in particular nanoscale, fibers particularly metallic, magnetic (with soft magnetism and / or hard), or Absorbable or excitable in the ultraviolet (UV), visible or infrared (IR) and particularly the near infrared (NIR), the flat and format relatively small such as boards, pigments or agglomerates of pigments especially absorbent or excitable under laser illumination or in ultraviolet (UV) light, visible or infrared (IR), particularly the near infrared (NIR), and security threads (generally based on plastics, in particular of polyester) including in particular a at least partial, metallic, metallic, iridescent or magnetic coating (at soft and / or hard magnetism), the coating possibly including reasons in positive or negative and the reasons which can be obtained in particular demetallization, WO 2009/136059

24 PCT / FR2009 / 050594 chemical or biochemical reagents for tampering and / or authentication and or identification may in particular react with at least one agent respectively falsification and / or authentication and / or identification, and the elements optically variables including holograms, liquid crystals, pigments iridescent or mirror effect structures, in particular dielectric layers, and their combinations.
The fibrous substrate may in particular comprise safety elements visible to the naked eye but it can also include tracers present in form active material, particles or fibers, capable of generating a signal specific when these tracers are subjected to an optronic, electrical excitation, magnetic or electromagnetic. These tracers constitute an identifiable substance thanks to a distinctive property and used to mark an element (a document of security in the present case) and ensure its follow-up, follow-up of its evolution or allow its recognition, its authentication or identification.
The dielectric structures with mirror effect consist of an alternation of layers of high and low index, for example respectively of the dioxide Hafnium and silica, and may in particular be obtained by ion etching.
According to a particular case of the invention, the fibrous substrate comprises at least a chemical or biochemical reagent of tampering and / or authentication and or identification device reacting in a colored manner, with at least one agent respectively falsification and / or authentication and / or identification.
The fibrous substrate may be based on fibers as described above for tape.
According to a particular case of the invention, the fibrous substrate and the ribbon are at base of the same fibers, that is to say that their fiber composition is the same in kind and preferably in the same proportions, this allows a good affinity between the two components and can, in addition, be an additional means of authentication.
Security sheet Another subject of the invention is, according to another of its aspects, a sheet having a fibrous ribbon partially embedded in a fibrous substrate realized at using a single-jet paper machine, the ribbon having at least one face, which is located in WO 2009/136059

25 PCT / FR2009 / 050594 hollow or protruding from the vellum of the leaf and which is no fully covered by the substrate.
Another subject of the invention is, according to another of its aspects, a sheet comprising a fibrous ribbon and a fibrous substrate, at least one element of security being placed at the level of the ribbon, in particular superimposed on the ribbon and having a thickness who is at least partially compensated by a difference in thickness between the ribbon and vellum of the sheet and / or an opening of the ribbon.
Another subject of the invention is, according to another of its aspects, a sheet having a first and a second fibrous jet contiguous with each other, the first draft having a ribbon, fibrous or not, forming a sub-thickness on the face of the first draft opposed to the second throw, and the second throw with an adjournment coming from superimpose less partially, preferably exactly, with an opening of the ribbon.
Another subject of the invention is, according to another of its aspects, a sheet having two fibrous jets contiguous with each other, each jets having a ribbon, fibrous or not, each forming a sub-thickness on each of the faces of the no jets next to each other, each ribbon having an openwork, the openings overlapping at least partially, preferably exactly.
Another subject of the invention is, according to another of its aspects, a sheet having two fibrous jets contiguous to each other, each having a ribbon, fibrous or no, each creating a sub-thickness, the under-thickness being superimposed at least partially, preferably exactly, between them, so as to the jets a cavity that can accommodate another ribbon, fibrous or not.
Another subject of the invention is, according to another of its aspects, a sheet comprising a fibrous substrate comprising two ribbons, fibrous or not, forming two sur-thicknesses on the surface of the sheet, the ribbons being spaced apart the other way to to be able to place a security element between the two ribbons.
The sheet can be obtained by the method described above. In particular, the sheet may include any of the features mentioned previously.
Security document The invention also relates to a security document comprising a sheet as defined previously.

WO 2009/136059

26 PCT / FR2009 / 050594 This document can be manufactured by cutting, association, binding, rolling, collage and / or laminating of this sheet.
More particularly, the security document can be a means of payment, such as a bank note, a check or a restaurant ticket, a document identity like an identity card or a visa or a passport or a driving license, a ticket a lottery, a ticket or an entry ticket to cultural events or sports.
Article to authenticate The invention also relates to an article to be authenticated comprising the sheet such defined or obtained previously, the article being selected from a security label, a package, including a package for medicines or for food or for cosmetics or perfumes or for electronic parts or for rooms spare parts, a sheet used in the medical or hospital field, especially a paper used to make sterilization wrappers, and still a paper Art.
The invention can be better understood in the following reading, from the description of nonlimiting examples of implementation of the invention and the examination of drawing figures, schematic and partial, in which:
FIG. 1 illustrates, in section, an example of incorporation of the ribbon according to the invention, - Figures 2 and 3 illustrate, in section, other examples of incorporation of ribbon according to the invention, - Figures 4 to 10 show, in section, examples of sheets according to the invention, FIG. 11 represents, in a view from above, the sheet of FIG. 10, FIG. 12 represents, in a view from below, the sheet of FIG. 10, and - Figures 13 to 15 show, in section, leaf variants according to the invention.
FIG. 1 illustrates an example of incorporation of a ribbon 3 in a method of manufacturing a sheet 1 according to the invention.
The process is carried out on a paper machine, partially shown, equipped with a lifting cylinder 40 and a round shape 4, partially WO 2009/136059

27 PCT / FR2009 / 050594 immersed in a fibrous suspension 5, and allows the formation of a sheet comprising a jet of a fibrous substrate 2 and a fibrous tape 3.
In this example, the fibrous tape 3 is introduced in direct contact with the form round 4 by one 9 of these faces before entering the fibrous suspension 5 allowing the formation of the substrate 2.
In this way, no fiber of the fibrous suspension 5 can be deposited on the face 9 of the ribbon 3 in contact with the round shape 4, in particular because the face 9 mouth the holes of the forming web of the round shape 4. The face 9 of the ribbon 3 can then be visible on the sheet 1 after manufacture.
Thus, only the face 6 of the ribbon 3, opposite to the round shape 4, can be covered or not with fibers of the fibrous suspension 5.
The ribbon 3 may have undergone treatment on at least part of the face 6 preventing any deposition of fibers from the fibrous suspension 5.
One or more sub-thicknesses or over-thicknesses can be formed at ribbon level 3 and one or more security elements can be applied at the level ribbon 3, in particular superimposed on under layers or juxtaposed with thicknesses.
After formation of the sheet 1 on the round shape 4 and draining of the fibrous suspension 5 on the web of the round form 4, the sheet 1 can be pressed then dried according to the current papermaking process.
According to an advantageous embodiment of the invention, the sheet 1 obtained before drying is married in the wet state with other jets whose fibrous compositions can be identical or different and can be formed on machines to flat table paper, forming roll or round form.
FIG. 2 illustrates another example of incorporation of a ribbon 3 into a method of manufacturing a sheet 1 according to the invention.
The method may for example be implemented on the same paper machine than that shown in Figure 1.
In this example, the ribbon 3 is introduced near the round shape 4 in the fibrous suspension 5 whereas fibers are already deposited on the form round 4.
In this way, none of the faces 6 and 9 of the ribbon 3 is in contact with the shape round 4. The ribbon 3 is in contact with the fibers that have already been deposited on the round shape 4 WO 2009/136059

28 PCT / FR2009 / 050594 before introduction of the ribbon 3 into the fibrous suspension 5. The face 9 of the ribbon 3 can then not be visible on the sheet 1 after manufacture.
Thus, the two faces 6 and 9 of the ribbon 3 can be covered, at least partially, fibers of the fibrous suspension 5.
It is possible to obtain one or more under-thicknesses or over-thicknesses at level of the ribbon 3 by any of the previously described ways.
One or more security features may be incorporated at the level or proximity of under-thicknesses or over-thicknesses.
After formation, the sheet 1 can be treated in the same manner as described previously.
FIG. 3 illustrates the possibility of incorporating the ribbon 3 into the sheet 1 bringing it into contact with the jet 2a formed on the round shape 4 at the outlet of the tank of form.
The ribbon 3 can be inserted between the jet 2a coming out of the shape tank and a jet 2b which can be achieved by any means papermaker.
In this case, an extra thickness may be formed on sheet 1 at the level of ribbon 3, this excess protruding protruding, for example on the face 2b jet and / or jet 2a.
FIGS. 4 and 5 show in section examples of sheets 1 obtained by a process according to the invention.
FIG. 4 illustrates a sheet 1 obtainable by the method illustrated on Figure 1.
The sheet 1 comprises a ribbon 3 whose face 9 is not covered with fibers of the fibrous suspension 5 and thus remains visible on the sheet 1.
The ribbon 3 may have a thickness eR less than that of the vellum of the leaf 1 or have undergone a particular treatment beforehand. In this way, a sub-thickness 7 is created on sheet 1 at the ribbon 3.
In this example in particular, the thickness e of the vellum of the sheet 1 is greater than the total thickness e2 of sheet 1 in the region of the sheet 1 where is the ribbon 3, this thickness e2 corresponding for example to the thickness eR of ribbon 3.
The thickness e of the vellum of the sheet 1, in particular of the substrate 2, corresponds to the sum of the thickness e2 and the value Ae of the under-thickness 7.

WO 2009/136059

29 PCT / FR2009 / 050594 FIG. 5 represents a sheet 1 that can be obtained by the process illustrated in Figure 2.
The sheet 1 comprises a ribbon 3 whose face 9 is entirely covered with fibers of the fibrous suspension 5 and is thus not visible on the sheet 1.
The ribbon 3 may have a thickness eR less than that of the vellum of the leaf 1 or have undergone a particular treatment beforehand. In this way, a sub-thickness 7 is created on sheet 1 at the ribbon 3.
In this example in particular, the thickness e of the sheet 1, in particular substrate 2, is greater than the thickness e2 of the sheet 1 where the ribbon 3. The thickness e is in particular equal to the sum of the value Ae of the under-thickness 7 and thickness e2 of the sheet 1 where the ribbon 3 appears, the latter being itself equal to the sum of the thickness eR of the ribbon 3 and the thickness e 3 of the fibers of the suspension fibrous 5 to contact of the face 9 of the ribbon 3.
The under thickness 7 created can allow the incorporation of one or several security elements on the sheets 1 of FIGS. 4 and 5.
In the examples described above and hereinafter, the different thicknesses can be equal to the previously mentioned values.
In particular, the thickness eR of the ribbon 3 may be greater than 10 m, preferably between 20 and 120 m and more preferably between 30 and 80 m.
The value Ae of the under-thickness 7 may be greater than or equal to 15 m, preferably at 30 m, more preferably at 60 m.
FIG. 6 shows an example of sheet 1, for example be obtained by the process illustrated in Figure 1.
The sheet 1 comprises a ribbon 3 at the level of which is a sub-thickness 7.
The ribbon 3 comprises an electronic device 20, in particular in the form an RFID device, for example incorporated in the ribbon 3 during manufacture ribbon 3.
One or more security elements may be incorporated in sheet 1 at level of the face 6 of the ribbon 3, in particular to protect the device electronic 20.
In addition, a second jet or a film may come to cover the substrate 2 on the of the face 6 of the ribbon 3 to protect the electronic device 20.
In this example, the thickness e2 of the sheet 1 where the ribbon 3 appears matches to the thickness eR of the ribbon 3.

WO 2009/136059

30 PCT / FR2009 / 050594 Fig. 7 illustrates another example of sheet 1, in which the ribbon 3 comprises an electronic device 20, in particular in the form of a RFID device, which is fixed, for example by gluing, on the face 6 of the ribbon 3.
The electronic device 20 has, for example, a width substantially equal to the width of the ribbon 3.
The value Ae of the under-thickness 7 can for example completely compensate the thickness eD of the electronic device 20.
The thickness e2 of the sheet 1 in which the ribbon 3 appears may be equal to the sum of the thickness eD of the electronic device 20 and the thickness eR of the ribbon 3.
FIG. 8 shows an example of sheet 1 that can be obtained by the method illustrated in Figure 1.
In this example, the ribbon 3 has a thickness eR greater than that of the vellum of the sheet 1 and in this way, an over-thickness 8 is created at the level of the side 6 of the ribbon 3. The over-thickness 8 may have an Ae + value which corresponds to the difference between thickness eR of the ribbon 3 and the thickness e of the vellum of the sheet 1. The thickness e2 of the sheet 1 where the ribbon 3 corresponds to the thickness eR of the ribbon 3.
The value Ae + of the over-thickness 8 may be less than 20 m.
The ribbon 3 may advantageously comprise polyethylene fibers.
As a result of a hot embossing of the face 6 of the ribbon 3, the fibers of polyethylene can melt and be made transparent.
In this way, it is possible to create a particular relief 11 on the surface of the face 6 of the ribbon 3 which can remove the over-thickness 8 previously existing.
embossing can for example allow to obtain a face 6 of the ribbon 3 substantially flat and substantially in the extension of the substrate 2 or to achieve a window or a reduced opacity band without obtaining a difference in thickness with respect to substrate.
It is also possible to obtain a transparency of the face 6 of the ribbon 3 that can create visual effects observable both in reflection and in transmission.
In addition, the relief 11 created also makes it possible to obtain tactile effects at level of the face 6 of the ribbon 3.
FIG. 9 shows a sheet 1 comprising two jets 2a and 2b.

WO 2009/136059

31 PCT / FR2009 / 050594 The jet 2a carries the ribbon 3, the latter having for example been incorporated into the jet 2a according to the method described above with reference to FIG.
The second jet 2b is for example attached to the first jet 2a on the side of this this which is opposed to the under-thickness 7. The second jet 2b may comprise, as illustrated, an ajour, for example a window 22b, which can be superimposed with a ajour, by example a window 22a, ribbon 3.
The under-thickness 7 can accommodate a security element 21 and the presence of the window 22b superimposed on the window 22a can be used to observe the face inside 2la of the security element 21 from the outer face of the jet 2b.
To manufacture the sheet 1 shown in FIG. 9, it is possible to manufacture the first throw 2a with the ribbon 3 and perform the wet wedding first and second jets 2a and 2b. The assembly formed by the two jets 2a and 2b and the ribbon 3 can be perforated so create the openings 22a and 22b and the security element 21 can be laminated with the first throw 2a so as to be superimposed on the ribbon 3 and, for example, to assemble with that this.
In a variant not shown, the second jet 2b does not include the ajour 22b, but may for example include an ink impression aimed at the transparentiser.
The security element is for example a transparent film 21, which is thicker than the transparent films usually used in the prior art.
The transparent film 21 can be introduced online, for example between two jets papermakers or on a single jet when it is sufficiently formed. he can alternatively be introduced offline, for example by a lamination process and / or lamination.
The transparent film 21 may for example be made of stretched polyester or polycarbonate stretched, and may have a thickness greater than or equal to 30 m, of preferably greater than or equal to 40 m. The transparent film 21 can still include patterns, obtained for example by laser engraving or intaglio printing on the movie transparent 21.
The transparent film 21 may still be an ink, a varnish or a resin.
In the case not shown where the ribbon comprises an electronic device, the transparent film 21 can protect the electronic device.
The transparent film 21 can still be made of a textile glued or fixed in the under-thickness 7.

WO 2009/136059

32 PCT / FR2009 / 050594 In this example, the thickness e of the transparent film 21 corresponds substantially at the value Ae of the under-thickness 7, being for example equal to 40 m.
The jet 2a may for example have a thickness e of 115 m.
FIG. 10 shows a variant embodiment of a sheet 1 according to the invention comprising two paper jets 2a and 2b each having a ribbon corresponding 3a and 3b, these tapes 3a and 3b having for example been introduced in the jet corresponding according to the method described with reference to Figure 1.
Each jet 2a and 2b respectively has a sub-thickness corresponding 7a and 7b related to the respective presence of the ribbon 3a and 3b.
In the illustrated example, the two jets 2a and 2b are assembled in such a way than the under-thicknesses 7a and 7b formed in the respective substrates are directed to opposite sides of the sheet 1.
Each sub-thickness 7a or 7b accommodates a security element corresponding 21 and 23. The respective thicknesses es and es' of the elements of security 21 and 23 correspond for example substantially to the under-thicknesses 7a and 7b.
The ribbons 3a and 3b may each comprise a corresponding aperture 22a and 22b, these openings can be superimposed at least partially, preferably exactly.
The security elements 21 and 23 are preferably not entirely opaque, in order to make it possible to observe in transvision particular effects, through openings 22a and 22b.
The transparent film 21 may for example have a thickness es of 20 m. The For example, the transparent film 23 may have a thickness of 15 m. The ribbon 3 can by example have a thickness eR of 60 m. The values Ae and Ae 'of the sub-thicknesses 7 can respectively fully compensate the thicknesses es and es' of the films 21 and 23.
The thickness e of the vellum of the sheet 1 can correspond to the sum of the thicknesses and es' of films 21 and 23 and eRa and eRb thicknesses of ribbons 3a and 3b.
In a particular embodiment, the transparent films 21 and 23 can be fluorescent with different colors.
The transparent films 21 and 23 can make it possible to obtain the effects optical previously described. They may for example include patterns allowing observation of other patterns by moiré and / or combinatorial effects.

WO 2009/136059

33 PCT / FR2009 / 050594 In the examples of FIGS. 9 and 10, one or more security elements 21 and 23 could alternatively extend at least partially in one or several openings 22a and 22b, although not shown.
FIGS. 11 and 12 represent respectively a top view and a view of below, sheet 1 of FIG.
In these two figures, we can then observe in transvision at the level of in days 22a and 22b a color that corresponds to the sum of the colors of the two films transparent 21 and 23.
On the other hand, apart from the openings 22a and 22b and always at the level of the ribbon 3, the color of the transparent film 21 is observed in the case of FIG. 11 and the color of transparent film 23 in the case of FIG.
FIG. 13 represents an embodiment variant in which the sheet 1 has two jets 2a and 2b each having a corresponding ribbon 3a and 3b having allowed to create a corresponding under-thickness 7a and 7b.
In the example of this figure, the two jets 2a and 2b are assembled with the underlayers 7a and 7b facing each other so as to arrange between both jets a cavity that can accommodate, as shown, a third ribbon 3c.
Each jet 2a and 2b can be made with its corresponding ribbon 3a and 3b and the third ribbon 3c can be introduced between the jets at the time of assembly.
The third ribbon 3c can be any security element.
FIG. 14 shows a variant embodiment in which the jet of substrate 2 is formed in contact with a round shape whose fabric T comprises a relief R
making it possible to make a recess 50 on the substrate 2.
The ribbon 3 is incorporated in the fibrous suspension after some thickness e3 has accumulated on the relief R of the fabric T.
a paper jet having on the side of the ribbon 3 a sub-thickness 7 and the opposite side also a sub thickness 50, related to the presence of relief R.
The jet thus manufactured can accommodate in the under-thickness 7 any element of security, like the examples previously described.
FIG. 15 shows a sheet 1 in which the substrate 2 door two ribbons 3 which are spaced a distance d for example from 3 to 20 mm.

WO 2009/136059

34 PCT / FR2009 / 050594 The thickness e3 of substrate under each ribbon 3 is identical, as illustrated, but it could alternatively be different, if the ribbons are introduced in contact with accumulated fibers on the round fabric at different locations and / or the thicknesses ribbons 3 are different.
In the example considered, the ribbons 3 each form an excess thickness of height 4th + and the space 60 formed between the extra thicknesses created by the ribbons 3 welcomes a security element 21 that can be any, including one of those previously mentioned.
This security element 21 has a thickness es which is for example less than 4e + or equal, so as to be protected vis-à-vis a risk of crushing by the presence of ribbons 3.
Of course, the invention is not limited to the embodiments which have just been described.
In the examples previously described, the ribbon (s) of the sheet according to the invention are fibrous. Alternatively, this or these ribbons could be no fibrous, by example be synthetic ribbons, for example formed by cutting films thermoplastic.
The expression having one is synonymous with having at least one.

Claims (28)

1. A process for the papermaking of a sheet (1) comprising at least one at least one jet (2a, 2b) of a fibrous substrate (2) and at least one ribbon (3, 3a, 3b), in which the ribbon (3, 3a, 3b) is introduced:
a) in a fibrous suspension (5) of a round-shaped paper machine (4) allowing the formation of the jet (2a, 2b), or b) in direct contact with the round shape (4), or c) in contact with the jet (2a, 2b) formed, the point of introduction of the ribbon (3, 3a, 3b) being chosen so as to create at least one under-thickness (7) or an extra thickness (8) on the sheet (1) at the ribbon (3, 3a, 3b), the under-thickness (7) being due to a reduction in the drainage of the fibrous suspension (5) by the ribbon (3, 3a, 3b), at least one security element (21, 23) being incorporated at the sub-level thickness (7) whose thickness (es, es,) is at least partially compensated by the sub-thickness (7) or being juxtaposed with the ribbon (3, 3a, 3b) at the excess thickness (8), the security element (21) having a thickness at least partially compensated by the extra thickness (8). 2. Method according to claim 1, the ribbon (3, 3a, 3b) being introduced at direct contact of the round shape (4), by one of its faces (9), before to enter the fibrous suspension (5). 3. Method according to claim 1, the ribbon (3, 3a, 3b) being introduced into the fibrous suspension (5) while fibers have already deposited on the round shape (4) at point of introduction of the ribbon (3, 3a, 3b). 4. Method according to claim 1, the ribbon (3, 3a, 3b) being introduced at contact of the jet (2a, 2b) formed of the fibrous substrate (2). 5. A method according to any one of the preceding claims, the ribbon (3, 3a, 3b) being fibrous. The method of any one of the preceding claims, the jet (2a, 2b) of paper formed on the round shape (4) and comprising the ribbon (3, 3a, 3b) being brought together in wet part of the paper machine with another paper jet (2a, 2b) coming superimpose on the ribbon (3, 3a, 3b). 7. A method according to any one of the preceding claims, the jet (2a, 2b) of paper formed on the round shape (4) and comprising the ribbon (3, 3a, 3b) being reunited by against-bonding with another jet (2a, 2b) of paper superimposed to the ribbon (3, 3a, 3b). The process according to any one of the preceding claims, except claim 4, the ribbon (3, 3a, 3b) having at least one of its faces (6, 9) no fully covered by fibers of the fibrous suspension (5) at the exit from paper machine with round shape (4). 9. A method according to any one of the preceding claims, the ribbon (3, 3a, 3b) having a thickness (eR) less than the thickness (e) of the vellum of the sheet (1). The method according to any of claims 1 to 8, the tape (3, 3a, 3b) having a thickness (eR) greater than the thickness (e) of the vellum of the sheet (1). 11. A method according to any one of the preceding claims, the ribbon (3, 3a, 3b) being embossed, in particular a hot embossing, especially at an extra thickness (8). The method according to any one of the preceding claims, wherein thickness (7) having a value (.DELTA.e-) greater than or equal to 15 μm, especially at 30 μm or at 60 μm. 13. Method according to any one of claims 1 to 11, the overthickness (8) having a value (.DELTA.e +) less than or equal to 20 μm. 14. A method according to any one of the preceding claims, the ribbon (3, 3a, 3b) being a paper ribbon. The method of any one of the preceding claims, except the claim 5, the ribbon (3, 3a, 3b) having non-fibrous elements. 16. A method according to any one of the preceding claims, the ribbon (3, 3a, 3b) having a width of between 2 and 60 mm, preferably between 4 and 30 mm and more preferably between 10 and 20 mm. 17. A method according to any one of the preceding claims, the ribbon (3, 3a, 3b) having a thickness (eR, eRa, eRb) greater than 10 μm, preference included between 20 and 120 microns, and more preferably between 30 and 80 microns. 18. A method according to any one of the preceding claims, the ribbon (3, 3a, 3b) having an electronic device (20), in particular a device to integrated microcircuit, in particular an RFID device. 19. A method according to any one of the preceding claims, the ribbon (3, 3a, 3b) comprising at least one adhesive, in particular a heat-sealing agent. 20. A method according to any one of the preceding claims, the ribbon (3, 3a, 3b) being made from a material which has previously undergone a Treatment of wet strength (REH). 21. A method according to any one of the preceding claims, the ribbon (3, 3a, 3b) having one or more openings (22a, 22b). 22. Process according to any one of the preceding claims, except claim 13, the sheet having on both sides of the ribbon (3, 3a, 3b) a sub-group thickness (7) in which at least partially at least one element of security (21, 23). 23. Method according to the preceding claim, the security elements (21, 23) having a film extending parallel to the ribbon (3, 3a, 3b) at its contact. 24. Method according to the preceding claim, the ribbon (3, 3a, 3b) comprising an opening (22a, 22b), the security elements (21, 23) being observable in transvision ribbon level (3, 3a, 3b). 25. A method according to any one of the preceding claims, except the claim 13, at least one electronic device (20), in particular a device to integrated microcircuit, being at least partially housed in the under-thickness (7), the sub thickness (7) at least partially offsetting the thickness (eD) of the device electronic (20). 26. Sheet (1) comprising a ribbon (3, 3a, 3b) and a fibrous substrate (2), at at least one safety element (21, 23) being placed at the level of the ribbon (3, 3a, 3b) in particular superimposed on the ribbon (3, 3a, 3b), and having a thickness (eS, eS ') which is at least partially compensated by a difference in thickness between the ribbon (3, 3a, 3b) and the vellum of the sheet (1) and / or by an opening (22a, 22b) of the ribbon (3, 3a, 3b). 27. Sheet according to the preceding claim, the ribbon (3, 3a, 3b) being fibrous. 28. Security document comprising a sheet (1) as defined in Claim 26 or 27.