EP1104349B2 - Method for making safety labels - Google Patents

Abstract

The invention concerns a method for making safety labels which consists in producing a base deposit on the film (100), then in defining a label shape (101). It further consists in producing (102) a printed window preferably by photogravure with cells bordered by a stripe forming the window outline; printing (103) the printing window on the base deposit with a passivation coating, and developing the window (104) by a physico-chemical operation.

Description

The present invention relates to a method for manufacturing security labels for protecting products as well as labels obtained according to this method.

The development of reprographic techniques makes it increasingly easy to copy documents or falsify them, and in particular, that of fiduciary papers, banknotes, stamps, etc.

Verifying the authenticity of a product consists of verifying the authentication and security elements carried by the product. These authentication and security elements are generally constituted by markers integrated into the product and that only a detector can read. The verification may consist in comparing the nature, the form and the position of the authentication and security elements with model authentication and security elements memorized in an inaccessible and / or tamper-proof manner in the device carrying out the verification. This is true of products such as banknotes. These products include cue and control elements integrated in the notes, generally readable with light radiation of precise wavelength, preferably in the field of non-visible light.

But the improvement of the means of analysis available on the market makes it increasingly difficult to carry out effective countermeasures, that is to say means preventing unauthorized persons from analyzing and knowing clearly the reference elements. and authentication and security and, consequently, to use this knowledge to falsify the products, that is to say the authentication and security elements that, read by a detector, are interpreted by it as corresponding authentic and secure authentication elements and not fake.

In the field of authentication and security security, it is certainly possible, by implementing significant means, to make an object or a product difficult to falsify or, at least, to make this falsification sufficiently difficult for it not presents no more interest.

This is not the case for products manufactured or used in large numbers, such as banknotes or fiduciary papers; for these, the cost of manufacture and in particular the cost of security means is a determining factor.

In other words, for such products, the means of security or protection against forgery are necessarily integrated in an industrial process and must be compatible with such implementation conditions. They must be related to a usual manufacturing cost, not excessive, and belong to the domain of the single copy with prohibitive costs.

The different economic and technical requirements limit the possibilities of protection to the available industrial means. Thus, at present, the printing of banknotes, fiduciary papers, stamps, uses conventional printing techniques whose precision limits of printing and positioning of the authentication and securing elements are those of conventional printing techniques. .

The integration of authentication and security elements in the form of holograms and means consisting of optically variable and diffracting images is tainted with the same physical error limits and therefore does not provide the necessary security.

These means consist of optically variable and diffracting images called DOVID are characterized by different images appearing, depending on the angle of observation, obtained by angulation of micro reliefs made during the stamping of the film by the matrix.

The present invention aims to develop a method to significantly increase the product safety against forgery by making these falsifications extremely difficult.

• on réalise un dépôt de base sur un film,
• on définit une forme d'étiquette,
• on réalise une fenêtre d'impression de préférence selon la forme de l'étiquette comme une surface gravée à cuvettes bordées par un filet continu formant le contour de la fenêtre,
• on imprime en repérage la fenêtre d'impression de préférence sur le dépôt de base du film avec une enduction de passivation,
• on développe la fenêtre par un enlèvement électro-chimique de matière entourant la fenêtre
• on dégage l'étiquette et on la récupère.

For this purpose, the invention relates to a method characterized in that

• we make a basic deposit on a film,
• we define a form of label,
• a printing window is preferably made according to the shape of the label as an etched surface with cups bordered by a continuous thread forming the outline of the window,
• the printing window is preferably printed on the base deposit of the film with a passivation coating,
• the window is developed by an electro-chemical removal of material surrounding the window
• we release the label and recover it.

Thanks to the precision of the realization and the positioning of the authentication and securing elements constituting the label, it is possible to recognize an authentic product that is to say integrating an authentic label, with an increased security of several orders of magnitude.

The label is used as is or can be transferred to the surface and / or the core of the material for securing and authentication.

The precision of the realization of the label makes it possible especially to increase the complexity of the shape, either of the outline, of the inclusions or reserves or the placement of the elements of authentication and security and above all this makes it possible to integrate of a very difficult to detect, elements of authentication and security only detectable or noticeable under conditions compatible with the accuracy of the realization.

The impression cylinder, preferably gravure printing, is engraved with an image comprising zones engraved, the contours of which are surrounded by a continuous thread to allow high-resolution printing without serration.

Thus, the possible accuracy according to the invention for the realization makes it possible to increase unsuspectingly the accuracy of the detection and a contrario the precision or the dimensional reduction of the authentication and securing elements whereas, until now, this precision was largely limited by the risk of error due to inaccuracy of manufacture.

This precision makes it easier to conceal multiple authentication and security elements, imperceptible in the usual analysis conditions, since they are inexplicable and are well below the limits of currently conceivable errors.

Finally, this very high precision makes it possible to multiply the number of reference elements and to increase all the security with respect to falsifications.

This accuracy of implementation is largely related to the quality of the continuous thread which is of a thickness between 2 and 50 μ depending on the material to be deposited, preferably 20 μ.

And in particular, the continuous thread is distant from the cells of a distance of between 5 and 50 μ, preferably 20 μ.

The window defining the label to an outline combining concave and / or convex, curved and / or straight lines. The window may have a uniformly convex contour or contour with alternating concave and convex curves. This outline may be formed of curved segments and / or straight segments and includes negative and positive lettering and flourishes.

The complexity of the window is related to the complexity that we want to give to the label to make its falsification difficult or in the case of an integrated circuit, to adapt to the nature of the circuit.

According to another characteristic of the invention, the window having a contour is positioned laterally by the reading of a guide channel located on the coated strip, and is positioned longitudinally by the reading of a spot or marker whose signal allows the controlling the positioning of the window on the pattern or patterns carried by the coated strip, the assembly with a tolerance between 0.1 mm and 0.5 mm, preferably 0.2 mm.

According to the invention, the method of applying a window in registration and electro-chemical treatment can be repeated a certain number of times depending on the layers to be produced and for each layer a window will be defined. The operations performed at each layer can also be different. In one case, it may be an electro-chemical operation working by removing material. In another case, the operation may consist of a supply of material (for example an electrolysis with consumable electrodes). In a third case, the removal and the deposit are simultaneous. Similarly, the window is not necessarily the area delimited by a closed contour. The window may also be the area located outside a closed contour of more or less complex shape.

Finally, inside a window, we can have complementary or auxiliary windows each defining areas of smaller areas.

In the majority of cases, the support is a film and the base deposit is a metal deposit. However, other subjects can be considered.

In a particularly advantageous manner, the base deposit constitutes a hologram including in particular a metal base deposit. The identification of holograms and means consisting of optically variable and diffracting images or equivalent elements on the film is advantageously carried out by reference elements intended to cooperate with detectors fitted to the installation to enable precise positioning and registration for the positioning of the images. Windows.

The basic deposit may also constitute a background including a patterned background.

These different means make it possible to produce extremely complicated structures with very high precision, depending on the results to be obtained, for example the production of integrated circuits or protection elements against forgery. Generally in the description will be used the term "label" to encompass these different achievements.

According to another characteristic, the printed passivation coating is of a cellulosic and / or metallic and / or plastic and / or vacuum metallized plastic nature.

As a variant, the printed passivation coating is insoluble and is composed of a preferably nitrocellulose polymer comprising a filler of variable nature as a function of the subsequent use of the printed strip, in particular pigments or conductive or insulating fillers such as the metal oxides, preferably oxides of titanium, iron, boron, nickel, chromium, carbon, silica, ... pure or mixed.

According to another characteristic, the printed passivation coating is soluble and is composed of polymer preferably polyvinyl alcohol or any other polymer soluble in aqueous medium, but insensitive to the aqueous solution of development of the window.

The invention also relates to an installation for the manufacture of security labels, for the implementation of the method as described above and which comprises a supply station providing a strip with a coating, a position of printing with a rotogravure printing unit to apply on the strip printing windows, preferably gravure printing, followed at the output of an electrolysis station to perform an electrolysis on the strip, a washing installation for cleaning the surface of the belt, a drying station, a checkpoint and a winding station.

Thus, it comprises a set of machines and apparatus comprising a treatment zone where insoluble electrodes immersed in an electrolyte under current are arranged, allowing rapid corrosion of the non-printed zones of a pre-printed metallic or metallized film which licks at parade the surface of the electrolyte.

The aqueous solution of windows development is composed of a salt with its base or its associated acid such as NaOH and NaCl in a concentration of between 5 and 150 g / l, preferably 100 g / l.

According to another characteristic, the window development solution is an electrolyte composed of a salt with its base or its associated acid such as NaOH, NaCl and CuCl ₂ in a concentration of between 15 and 150 g / l, preferably 100 g. / l.

Advantageously, the temperature of the electrolyte is between 5 and 80 ° C. and is preferably equal to 40 ° C.

The electrical voltage across the electrodes is continuous between 2V and 21V, preferably equal to 6V.

In the electrolysis station, the electrode is a bar having a section with a geometry favorable to the concentration of current flows to the metal film to be corroded, by a triangular shape of which one of the vertices of the triangle is directed towards the film.

The material of the electrode is an insoluble matter in the aqueous developing solution even under electric current such as titanium.

According to another characteristic, the installation is composed of a set of machines and apparatus comprising a treatment zone with soluble electrodes immersed in an electrolyte under current for rapid deposition on a preprinted film of windows.

In this installation, the developing solution is an electrolyte composed of a salt with its base or its associated acid such as CuCl ₂ and HCl in a concentration of between 5 and 150 g / l, preferably 100 g / l.

It is also interesting that the current across the electrodes is a direct current applied at a voltage of between 5 and 30V, preferably 6V.

According to an advantageous characteristic, the section of the electrode bar has a geometry favorable to the dissolution of the metal of the electrode, so a maximum surface in contact with the electrolyte is for example a circular section.

In this case, the electrode material is a material soluble in the electrolyte, such as copper for depositing a copper film.

Advantageously, the anodes and the cathodes are immersed parallel to each other, separated by insulating partitions, perpendicular to the unwinding of the film, in the solution for developing the windows, at a distance of a few mm from the film, preferably at most 1 mm, which licks the surface of the electrolysis without immersing itself in it.

According to the invention, the section of the bar electrode has a geometry favorable to the concentration of current flows to the metal film to be corroded and favorable to its dissolution in the electrolyte, preferably a form of drop, the tip of which is directed to the film.

According to another characteristic, the installation comprises a set of machines and apparatus comprising a washing zone with spinning between steel cylinders and polymer cylinders to limit the entrainment and facilitate drying by evaporation of the washing liquid, so that the soluble passivation coating is dissolved and the treated film is dry and without trace of electrolyte incompatible with its subsequent use.

According to another characteristic, the installation is composed of a set of machines and appliances put online to constitute a machine with several separate stations so that the printing is separated from the other operations themselves grouped into a second machine.

According to another characteristic, the installation is composed of a set of machines and apparatus comprising two control zones between the printing and the treatment and a third one after drying, equipped with probes for the continuous detection of the conductivity of the different areas and video cameras to appreciate the respect of the resolution of the various stages of operations.

The invention also relates to the products obtained by the method and the installation.

Thus according to the invention, the product results from a film comprising multiple layers of insulating and conductive, insulating and metallic materials that can be used in the printing of fiduciary materials in order to secure them.

According to another characteristic, it is intended for the production of holograms and means consisting of optically variable and diffracting images, of optically variable images by diffraction or other, of security, identified and demetallized, or the thickness of the coating. passivation is between 0.5 and 8 μ, preferably 1 μ, to allow filling the irregularities of the support on which said patterns are transferred.

According to the invention it is intended for the production of a film comprising multiple layers of insulating and conductive, insulating and metallic materials that can be used in the printing of materials intended for the electronics industry.

Or it is intended for the electronics industry where the multiple layers are of thickness between 0.05 μ and 5 μ preferably 1 μ to limit the final thicknesses, but especially to achieve passivation coatings of high accuracy between 0.05 and 5 μ preferably 1μ.

The product is intended for the electronics industry where the metal layers are of a thickness of between 5 Angstrom and 600 Angstrom, preferably 50 Angstrom.

According to the invention, the product consists of patterns whose contours are smooth and do not have serration.

The product consists of patterns having a resolution of between 10 μ and 100 μ, preferably 50 μ, either lines or guilloches with a minimum thickness and a distance of between 10 μ and 100 μ, preferably 50 μ. .

The patterns are metallic patterns.

The product is also composed of a polymer film coated with holograms, metallic, DOVID or others, spotted, demetallized, cut in the paper during its manufacture, to make the patterns visible either by transparency or by reflection.

According to another feature, the product is composed of a polymeric film coated with a metallized release layer comprising holograms and / or DOVID where others, identified, demetallized, coated with the various layers necessary for its continuous transfer (stripe) and / or spotted (patch) on the final paper.

According to another feature, the product is composed of a metallized or non-coated metallized film comprising one or more holograms, DOVID or others, identified, demetallized, coated with the various laminated layers, cut in various ways, necessary for its cold adhesion on the final support, constituting an adhesive label or an overlay.

According to another characteristic, the product is composed of a metallized or non-coated metallized film comprising holograms, DOVID or others, identified, demetallized, laminated with another polymer, coated, cut or not, and which has the characteristics of destruction. images as soon as you try to unstick it from its final support, constituting a detachment film

The same products can be made without holograms, without DOVID or others.

• la figure 1 est un schéma synoptique du procédé de l'invention,
• la figure 2 est une vue d'ensemble d'une machine pour la mise en oeuvre du procédé,
• la figure 3 montre le détail du groupe d'impression,
• la figure 4 est une vue schématique du groupe d'impression avec système de repérage,
• la figure 5A montre une forme d'étiquette,
• la figure 5B montre un premier mode de réalisation d'une gravure héliographique de l'étiquette de la figure 5A,
• la figure 5C montre un second mode de réalisation d'une gravure d'étiquette sur un cylindre héliographique,
• la figure 5D montre le résultat de l'impression, à l'aide de la fenêtre d'impression, obtenue avec l'une des figures 5B; 5C,
• la figure 6 est un schéma d'un groupe de traitement électro-chimique du film,
• la figure 7 est une vue de dessus de la cuve d'électrolyse,
• la figure 8 est une vue en perspective de la cuve d'électrolyse
• la figure 9 est une vue schématique du système de contrôle vidéo.

The present invention will be described hereinafter in more detail with the help of the drawings in which:

• FIG. 1 is a block diagram of the method of the invention,
• FIG. 2 is an overall view of a machine for carrying out the method,
• FIG. 3 shows the detail of the printing unit,
• FIG. 4 is a schematic view of the printing unit with tracking system,
• FIG. 5A shows a form of label,
• FIG. 5B shows a first embodiment of a heliographic etching of the label of FIG. 5A,
• FIG. 5C shows a second embodiment of a label etching on a heliographic cylinder,
• Fig. 5D shows the result of printing, using the print window, obtained with one of Figs. 5B; 5C,
• FIG. 6 is a diagram of an electrochemical treatment group of the film,
• FIG. 7 is a view from above of the electrolytic cell,
• FIG. 8 is a perspective view of the electrolytic cell.
• Figure 9 is a schematic view of the video control system.

According to FIG. 1, the invention relates to a method of manufacturing security labels intended to be affixed to products to be protected against falsification or else to be integrated in products such as, for example, holograms and means consisting of images optically. variable and diffracting, wires, ... in banknotes, fiduciary papers, packaging and security or authentication documents.

This process consists in preparing (100) a film with a base deposit, in general a metallic deposit on the plastic base film such as a support of a polyester or PVC and / or metallic and / or plastic nature, and / or or metallized plastic under vacuum.

The base deposit may form a pattern, i.e., a background, possibly constituting a hologram.

In parallel with this preparation is defined (101) the form of the label with the position of the authentication and securing elements intended to be hidden in the label and the reference points for operations that must be made by locating the position labels on the film.

After defining the shape of the label, the print window (102) is made. This is the area defined by the outline of the label and located within this label. All this surface will be printed by rotogravure.

For this, the window is made as an engraved surface with rotogravure cups bordered by a continuous thread forming the contour of the window. This window can have any shape, different from a rectangular or circular shape or, more generally, different from a simple geometric shape. Given the precision allowed by the process, it is particularly interesting to choose a complicated window contour that can be made with great precision and complete geometry and lettering of great fineness (50 μ and less) a very effective means of protection against forgery.

This printing window is made on a rotogravure cylinder.

Then with this print window (103), the window on the base repository is movie. The printing is done with a passivation product, resistant to the electro-chemical action that will be performed later. The printed window is positioned relative to the already printed tape, in longitudinal registration by means of a readable spot reader on the pre-printed tape whose signal is amplified and allows the drive motor of the printing cylinder to be controlled.

Thanks to a guide guide reader (BA1b) whose signal makes it possible to laterally move the strip (BA1) with respect to the printing windows with a tolerance of 0.1 to 0.5 mm, preferably less than 0.2 mm.

The lateral guidance system is provided by reading a guide corridor (BA1b) using a photoelectric cell (BB1) or the like, the signal of which is amplified to drive the band (BA1) laterally in such a way that that the guide corridor (BA1b) is always located laterally in the same way with respect to the corridor (B22) carried by the cylinder (B2). The enslavement of the longitudinal registration is stalled on the reading of the stamped spots (BA1c) traced with each revolution of the rotary tool carrying the stamping die patterns (BA1a), spots (BA1c), and the guide corridor (BA1b). The measurement and recording of the distance between said spots (BA1c) is exploited by computer to establish the statistics of the longitudinal positioning gaps, to determine the quality of these same positions and to give an alert when working out of tolerance.

The signals emitted by the photoelectric cell (BB2) are compared with those of the encoder (BB3) to determine and control the power supply (BB4) of the motor (BB5) driving the cylinder (B2) carrying the printing windows (B21).

A video control system makes it possible systematically to check by a first camera (F1) the slaving of the longitudinal and lateral positioning, and in a random manner by a second camera (F2), the quality of the printing of the windows (I) .

It should be noted that the dimension of the impression cylinder is greater than that of the patterns of the strip (BA1) to ensure its tension. The slaving of the longitudinal registration is set on the reading of the stamped spot having the interspot (distance between two master spots) the most regular, the master spot (BA1c), which alone will be read. Each read interspot will be measured. These measurements are used to establish the longitudinal positioning error statistics, to determine the quality of these same positions and to give an alert when working outside tolerance. A video system makes it possible systematically to check, by a first camera, the servo-control of the longitudinal and lateral positioning, and in a random manner by a second camera, the quality of the printing of the windows.

After this printing, the window (104) is developed, that is to say that the film is electrochemically actioned, for example an electrolysis, with removal in order to remove the base deposit of the film. wherever the deposit is not protected by the passivation layer deposited by printing (103). This consists of removing all parts of the base deposit located outside the print window.

As the basic deposit is generally a metallic deposit, it is very interesting to develop the window by an electrochemical action such as an oxidation-reducing attack or an electrolysis according to the reaction rate and the efficiency that the reaction must present. surgery.

At the end of this electrochemical action, the base deposit is removed from the film except at the locations corresponding to printing of the printing window.

Then, possibly after this operation, the label (105) is recovered by removing the soluble passivation deposit covering the rotogravure windows. The film is washed and the label is thus obtained on the film forming the support.

The label can then be attached to the product to be protected or be integrated therein (106). The possibilities are multiple.

It is also possible to proceed in negative, in a reverse manner to the above method. The surface of the strip can be passivated outside the window and the surface inside the window treated by electro-chemical action.

Moreover, in addition to this "reversibility" of the process, it is also possible to envisage an electro-chemical action consisting in depositing a coating layer on the outside or inside the window, outside the passivation layer previously deposited on the film.

The shape of the window to be made can be very variable in size and complexity.

The label corresponding to the window may also comprise an electronic circuit made if necessary by the multiplication and repetition of the operations described above:

The impression of a different window then its development and so on and finally the recovery of the "label".

Figure 2 shows an installation for carrying out the method described above. This installation consists of a feed station A which receives the film provided with its base deposit BA1, wound on a reel. In this feed station, the reel is unwound to feed a gravure printing station B; then, at the output of this printing station by gravure, the band BA2 goes to an electrolysis station C performing the electro-chemical treatment on the windows of the film BA3. This electrolysis station C is followed by a washing station D in which the soluble passivation layer giving the film BA4 is optionally removed and the strip is rinsed. Then the band BA4 goes into a drying station E and finally into a control station F to arrive on the winder G.

The supply station A includes a unwinder A1 which carries the coil A2. This unwinder is driven by a motor controlled by a call group A3, which sets a controlled voltage in the band BA1. The strip then passes into the printing station B which comprises a printing unit (FIGS. 3 and 4) with an ink fountain B1, a gravure cylinder B2 immersed in the ink fountain B1 to cover the surface provided with photogravure cavities and the outline of the window. This cylinder cooperates with a doctor blade B3 which removes the ink on the surface to leave only the ink inside the cells or etching. The inkwell B1 is fed from a reservoir B4 containing the coating product by a pump B5 and a pipe B6. The tank B4 is equipped with a viscosity detection means B6 such as a viscometer to make it possible to adjust the viscosity of the coating liquid.

This rotogravure group B can be equipped with a spot reading system disposed on the metallized strip which will allow the control of the strip, so that the positioning of the window will be in register with the patterns of the metallized strip comprising patterns and drawings possibly pre-printed.

The liquid level in the inkwell B1 is adjusted by an overflow B7 with return to the tank B4, so that the rotogravure cylinder B2 is always immersed at the same depth in the inkwell B1.

The cylinder B2 cooperates with a pressing roll B10 placed above the band BA1, the cylinder B2 being below the band.

The band BA1 is schematically composed, as indicated in FIG. 3, of a plastic support S and a base coating M such as a metal.

Turning in the direction of the arrows, the gravure cylinder B2 compresses, with the B10 presser, the band BA1 and deposits the printing or coating I corresponding to the windows.

Figure 4 is a top view of the printing unit shown in Figure 3. This figure shows the gravure cylinder B2, the pressing cylinder B10 with an arrow indicating the compression and the band BA in top view. The gravure cylinder B2 carries a surface engraved according to a printing window B21 of relatively complicated form, which makes the impression I or coating area on the lower face M of the band BA1 (now become the band BA2).

Figures 5A-5D show more explicitly the realization of the engraved surface of the printing window.

Figure 5A gives the desired contour for the heliographic window, i.e. the outline of the future label (I100).

From this form I100, the surface of the printing window in the cylinder is engraved. This window is constituted by an etched surface comprising cuvettes or cells K100, separated by K101 mu-rets, and the assembly is surrounded by a continuous thread K102, which borders the cuvettes and the intervals between the cuvettes K100.

In this figure, the cells are represented by black squares with rounded corners possibly truncated, separated by walls (partitions or called bridges) K101, white.

The set of cells or cuvettes is here surrounded by a continuous thread, that is to say a very narrow notch which fills with ink but limits the spreading of the ink of the cells to give the printed image , a continuous contour, precise, precisely and predetermined limiting the limit of the window.

In FIG. 5B, this thread K102 passes contiguously on or adjacent the bowls.

In the case of FIG. 5C, the window 1200 also comprises K200 cells separated by walls K201 and the assembly is surrounded by a continuous thread K202 which is further from the edge of the cells K200 (truncated or not) than in the embodiment of Figure 5B.

The fineness of the line constituting the continuous net depends on the resolution of the tracer which has drawn the window or windows; thus, with the choice between the etching forms of FIGS. 5B and 5C, the viscosity of the liquid used for this printing depends. As indicated, this liquid is, once dried, a passivation product, that is to say inert vis-à-vis the electro-chemical action to be performed.

The adhesion of this passivation product to the coating of the film, as well as that of the subsequently deposited layers is a function of the residual solvents and the nature of the resins employed. Residual solvents of the passivation layer is between 150 and 5 mg / M ^2/24 hrs preferably 15 mg / M ^2/24 hours

The resin of the primer layer (primer) deposited on the passivation coating is compatible with the latter and thus a delamination resistance of between 1000 g / m ² and 200 g / m ² , preferably 500 g / m, is obtained. ² .

The higher layer for heat resistance (varnish 2 components) and that providing the moisture resistance of the fusible and all the others, having a total residual solvents content of between 150 m and 50 mg / M ^2/24 H preferably 15 mg / M ^2/24 hrs and a delamination strength between 200 and 1000 g / M ^2, preferably 500 g / M ^2.

Finally, FIG. 5D shows the printed image 1300 with its very precise contour and not serrated.

In return to FIG. 2, the electrolysis station C consists of an electrolysis tank C1 which is licked by the band BA2, having received the impression in the printing station B. This electrolysis station also comprises an extractor hood C2 of the electrolysis gases. The detail of station C2 appears in Figures 6, 7, 8.

The schematic side view of FIG. 6 of the electrolysis station C: shows an alternation of electrolysis trays C3, C4, C5, C6 connected by lines C7 and a supply pump C8 to a reservoir of electrolyte C9. In fact, the band BA2, equipped with coatings I, touches the surface of the liquid contained in the electrolysis trays C3-C6. In these different tanks there is each time a C10 electrode, C11, C12, C13, opposite polarities and electrolysis is a tray to another.

At the outlet there is a collection hopper C15 which collects the liquid dripping from the strip BA3 drained by its passage between two cylinders C16, C17. The wringing liquid is collected in the hopper C15 and returns to the tank C9.

Figure 7 shows a top view of the electrolysis group C1, revealing in particular the partitions C20, C21, C22 separating the tanks. This figure also shows the union of the positive and negative electrodes to a common collector rail C30, C31.

Figure 8 shows in perspective view the organization of the electrolysis group C1. The same references as above were used but their description will not be repeated.

The conditions in which the electrolysis takes place depend on the nature of the metal to be electrolyzed. The electrodes are non-consumable electrodes, which simply remove the metallization of the film in places not protected by the passivation layer, that is to say outside the outline of the windows.

The situation is different if the electrolysis must deposit or remove and deposit a metallization layer as mentioned above.

Finally, the window printing and electrolysis operations can be repeated with different shapes of windows made on each other, for example to form an integrated circuit and in this case there will be a succession of positions B, C and possibly D that will alternate.

Then the film BA3 passes into the washing station D. This washing station rinses the tape BA3 to remove the electrolyte residue and dissolve the coating layer including the passivation layer. This washing station D consists of different return cylinders D1, D2 driving the band BA3 in a first tank D4 and then in a second tank D5. These tanks contain a rinsing liquid of the electrolyte and / or a solvent and coating. The detailed structure of these wash tanks will not be given. It is a set of cylinders defining a circulation pattern of the band in the washing bath.

The washing is done by spinning between steel cylinders and polymer cylinders to limit the entrainment and facilitate the drying by evaporation of the washing liquid, so that the film is dry and without trace of the electrolyte incompatible with its subsequent use.

Downstream of the washing station D, the band BA4 passes into the drying station E equipped with ventilation and air extraction means E1, E2, E3, E4 and, finally, the dried band BAS passes into a station. F control equipped with an F1 video camera that views an area of the BA5 film to control the quality of manufacture. This control is done continuously. At the output of control station F, the film is wound on a winding station G. This winding station has a similar structure to the unwinder A but operates in the opposite direction. It comprises a support G1 equipped with a motor forming the roll G2.

FIG. 9 schematically depicts the video control system composed of a video camera (F1) which records the image of the unwinding corridor (1 A) and the spots (1 C) appearing after processing of the computer (F4) on half of the screen (F3) in (IA) and (IC '). The camera (F2) visualizes the demetallized patterns (I) according to random positions and transmits the image to the computer (F4), the image (I ') appearing on the other half (F5) of the screen.

After control of the band, the band is dithered and wound with a tension control so that it is not deformed by the areas of extra thickness.

The control of the band through the installation of Figure 2 is synchronized using pins and readers and control circuits; these means are not represented.

The installation has the advantage of a treatment speed that can exceed the treatment speed of 250 m / min. The treatment is insensitive to the presence of the metal oxides which protect the metallized face of the film, which is notably an advantage over the prior chemical process. The possibility of depositing a metal layer of another nature than that which has been corroded allows the manufacture of metal multilayers.

The resolution of the metallized line obtained is that of the printing because the thickness of the corrosion mask may be 2 microns or less.

Finally, for questions of production opportunity, the printing of the corrosion reserve can be performed on machine independent of the processing machine.

The method and the installation described allow the realization of a film comprising multiple layers of insulating and conductive, insulating and metallic materials that can be used in the printing of materials for the purpose of securing or authenticating them or materials. intended for the electronics industry.

According to an interesting characteristic, the current across the electrodes is a pulsed current with or without inversion.

The product according to the invention is intended for producing holograms and means consisting of optically variable and safety diffracting images in which the thickness of the passivation coating is between 1 and 8 μ, preferably 4 μ, to enable fill the irregularities of the support on which the hologram will be transferred hot and under pressure.

This product is also intended for the electronics industry where the multiple layers have a thickness of between 0.05 μ and 5 μ, preferably 1 μ to limit the final thicknesses, but especially to achieve high passivation coatings between 0.05 and 5 μ, preferably 1 μ.

In addition, the product is intended for the electronics industry, where the metal layers are between 5 Angstroms and 600 Angstroms thick, preferably 50 Angstroms thick.

Claims (50)

1. Method for making safety labels intended to be fixed on products to be protected against falsifications or to be integrated therein by the authentication and security of long-series printed circuits, characterised in that

   - a base deposit is made on the film (100),

   - a label (101) shape is defined,

   - a printing window (102) is made preferably according to the label shape on a printing form comprising an engraved surface with cells bordered by a continuous stripe forming the out-line of the window, geometries, and letterings,

   - the printing window is printed with marking (103) on the film base deposit with a passivation coating,

   - the window is developed (104) by electrochemical removal of material surrounding the window,

   - the label is detached (105) and recovered (106) to use it as it stands or to transfer it (107) to the surface and/or core of the security and authentication material
2. Method according to claim 1, characterised in that the photogravure cylinder is engraved with an image comprising engraved zones whose outlines are surrounded by a stripe to permit high-resolution printing without any indentation.
3. Method according to claim 1, characterized in that the window has an outline combining concave and/or convex lines, curves, and/or straight lines.
4. Method according to claim 1, characterised in that the window having an outline is positioned laterally in relation to the reading of a guide channel located on the coated strip and positioned longitudinally in relation to the reading of a spot or marker whose signal allows positioning control of the window on the pattern(s) carried by the coated strip, with the whole set having a tolerance between 0.1 mm and 0.5 mm, preferably 0.2 mm
5. Method according to claim 1, characterised in that the base deposit is a metal deposit
6. Method according to claim 5, characterised in that the metal base deposit is composed of holograms and means composed of optically variable and diffracting images
7. Method according to claim 1, characterised in that the window is developed with marking by electrochemical removal of material surrounding the window
8. Method according to claim 1, characterised in that the base deposit corresponds to a base, particularly a patterned base
9. Method according to claim 8, characterised in that the base deposit corresponds to a base, particularly a base with means composed of optically variable and diffracting images
10. Method according to claim 1, characterised in that the printed passivation coating is of cellulose and/or metal and/or plastic and/or vacuum metallised plastic type or any other charge validating the security of documents, such as wires, patches, stripes, adhesive labels, detachable films, or the like
11. Method according to claim 7, characterised in that the printed passivation coating is insoluble and composed of a polymer, preferably a nitrocellulose polymer, incorporating a charge of variable type depending on the end use of the printed strip, particularly conductive or insulating pigments or charges such as metal oxides, preferably titanium, iron, boron, nickel, chromium, carbon, silicon, etc oxides used individually or in combinations
12. Method according to claim 11, characterised in that the passivation coating printed with marking is insoluble and composed of a polymer, preferably a nitrocellulose polymer, carrying a charge of variable type depending on the end use of the printed strip, particularly conductive or insulating pigments or charges such as metal oxides, preferably titanium, iron, boron, nickel, chromium, carbon, silicon, etc oxides used individually or in combinations
13. Method according to claim 1, characterised in that the printed passivation coating is soluble and composed of a polymer, preferably a polyvinyl alcohol polymer or any other polymer that is water-soluble but insensitive to the aqueous solution for window development
14. Method according to claim 13, characterised in that the passivation coating printed with marking is soluble and composed of a polymer, preferably a polyvinyl alcohol polymer or any other polymer that is water-soluble but insensitive to the aqueous solution for window development
15. Method according to claim 1, characterised in that the continuous stripe has a thickness ranging between 2 and 50 µm depending on the material to be deposited, preferably 20 µm
16. Method according to claim 1, characterised in that the continuous stripe has a distance from the cells, ranging between 5 and 50 µm, preferably 20 µm.
17. Installation for making safety labels and for implementation of the method according to any one of claims 1 to 11, characterised in that it incorporates a feeding station (A) supplying a strip (BA1) provided with a marking system coating, a printing station (B) with a photogravure printing set for application of printing windows on the strip (BZ2), preferably photogravure, followed on its downstream side by an electrolysis station (C) for carrying out electrolysis on the strip, a washing installation (D) for cleaning the strip surface, a drying station (E), an inspection station (F), and a coiling station (G)
18. Installation according to claim 17, characterised in that it incorporates a set of machines and equipment comprising a treatment zone provided with insoluble electrodes immersed in an electrolyte under a current allowing rapid corrosion of the non-printed zones of a metal or metallised preprinted film skims the electrolyte surface as it passes
19. Installation according to claim 18, characterised in that the aqueous solution for window development is composed of a salt with its base or acid associated, such as NaOH and NaCl, at a concentration ranging between 5 and 150 g/l, preferably 100 g/l.
20. Installation according to claim 18, characterised in that the aqueous solution for window development is an electrolyte composed of a salt with its base or acid associated, such as NaOH, NaCl, and CuCl₂, at a concentration ranging between 15 and 150 g/l, preferably 100 g/l.
21. Installation according to claim 18, characterised in that the temperature of the electrolyte ranges between 5 and 80°C, preferably being 40°C
22. Installation according to claim 18, characterised in that the electric voltage on the electrode terminals is continuous, ranging between 2 V and 21 V, preferably being 6 V
23. Installation according to claim 18, characterised in that the electrode is a rod having a section with a geometry favouring the concentration of current flows towards the metal film to be corroded, being of triangular shape with one of the triangle vertices being directed towards the film.
24. Installation according to claim 18, characterised in that the electrode material is a material insoluble in the aqueous development solution even under an electric current, such as titanium
25. Installation according to claim 17,characterised in that it is composed of a set of machines and equipment comprising a treatment zone provided with soluble electrodes immersed in an electrolyte under a current allowing rapid deposition on a preprinted window film
26. Installation according to claim 25, characterised in that the development solution is an electrolyte with its base or acid associated, such as CuCl₂ and HC1, at a concentration ranging between 5 and 150 g/l, preferably 100 g/l.
27. Installation according to claim 26, characterised in that the current on the electrode terminals is a direct current applied at a voltage ranging between 5 and 30V, preferably 6 V
28. Installation according to claim 26, characterised in that the current on the terminals of the electrodes is a pulsed current with or without inversion
29. Installation according to claim 25, characterised in that the section of the electrode rod has a geometry favouring the dissolution of electrode metal, accordingly a maximum surface in contact with the electrolyte, ie eg a circular section
30. Installation according to claim 25, characterised in that the electrode material is a material that is soluble in the electrolyte, such as copper to deposit a copper film
31. Installation according to claim 18, characterised in that the anodes and cathodes are immersed in parallel in relation to each other, being separated by insulating partitions, perpendicularly to uncoiling of the film, in the window development solution at a distance of several mm, preferably more than 1 mm, which skims the surface of the electrolyte without being immersed therein
32. Installation according to claim 17, characterised in that the section of the rod electrode has a geometry favouring the concentration of current flows towards the metal film to be corroded and favouring its dissolution in the electrolyte, preferably a teardrop shape whose tip is directed towards the film
33. Installation according to claim 17, characterised in that it is composed of a set of machines and equipment comprising a washing zone provided with drying cycles between steel cylinders and polymer cylinders to limit the drives and to facilitate drying by evaporation of washing liquid in such a way that the soluble passivation coating is dissolved and that the treated film is dry and free from any trace of electrolyte incompatible with its end use.
34. Installation according to claim 17, characterised in that it is composed of a set of machines and equipment comprising two inspection zones between printing and treatment and a third after drying, being equipped with probes for continuous detection of the conductivity of the different zones and with video cameras to verify that the resolution in different stages of the operations, longitudinal and transverse marking, and printing quality are being met
35. Installation according to claim 17, characterised in that it is composed of a set of machines and equipment arranged in line to provide a separated multi-station machine to ensure that printing is separated from the other operations themselves arranged in a second machine
36. Product resulting from implementation of the method according to any one of claims 1 to 16 or implementation of the installation according to any one of claims 17 to 35, characterised in that it derives from a film incorporating multiple layers of insulating and conductive materials or insulating and metallic materials able to be used in the printing of fiduciary materials in order to make them secure.
37. Product according to claim 36, characterised in that it is intended to produce holograms and means composed of optically variable and diffracting images, images optically variable by diffraction, or the like for security purposes that are marked and demetallised and where the thickness of the passivation coating ranges between 0.5 and 8 µm, preferably 1 µm, to make it possible to overcome the irregularities of the substrate onto which the said patterns are transferred
38. Product according to claim 36, characterised in that it is intended to produce a film incorporating multiple layers of insulating and conductive materials or insulating and metallic materials able to be used in the printing of materials destined for the electronic industry
39. Product according to claim 36, characterised in that it is intended for the electronic industry where the multiple layers have a thickness ranging between 0.05 µm and 5 µm, preferably 1 µm, to limit the final thicknesses, but moreover to produce high-precision passivation coatings with a thickness ranging between 0.05 µm and 5 µm, preferably 1 µm,
40. Product according to claim 36,characterised in that it is intended for the electronic industry where the metal layers have a thickness ranging between 5 Å and 600 Å, preferably 50 Å.
41. Product according to claim 36, characterised in that it is composed of patterns whose outlines are smoothed and have no indentation whose elementary printing points at the limit of printing technology are interconnected.
42. Product according to claim 36, characterised in that it is composed of patterns with a resolution ranging between 10 µm and 100 µm, preferably 50 µm, either lines or chequered elements with a minimum thickness and distance ranging between 10 µm and 100 µm, preferably 50 µm.
43. Product according to claims 40, 41, characterised in that the patterns are metallic patterns.
44. Product according to claim 36, characterised in that it is composed of a polymer film coated with metallic holograms, DOVID, or the like that are marked and demetallised, and which film is cut into threads having a width of 0.5 to 10 mm, preferably 1.2 mm, and deposited in the paper during the production thereof in order to make the patterns visible by either transparency or reflection
45. Product according to claim 36, characterised in that it is composed of a polymer film coated with metallised detachable layer incorporating holograms and/or DOVID or the like that are marked, demetallised, and coated with different layers necessary for its continuous transfer (stripe) on the final paper
46. Product according to claim 36, characterised in that it is composed of a polymer film coated with metallised detachable layer incorporating holograms and/or DOVID or the like that are marked, demetallised, and coated with different layers necessary for its marked transfer (patch) on the final paper
47. Product according to claim 36, characterised in that it is composed of a metallised coated polymer film incorporating one or more holograms, DOVID, or the like that are marked, demetallised, laminated with different layers, coated, and cut out in different ways as necessary for its cold adhesion on the final substrate comprising a label or overlay.
48. Product according to claim 36, characterised in that it is composed of a metallised coated or uncoated polymer film incorporating holograms, DOVID, or the like that are marked, demetallised, laminated with another polymer, coated, cut out or not cut out and which is characterised by destruction of its images as soon as an attempt is made to detach it from its final substrate comprising a detachable film.
49. Product according to claim 36, characterised in that the products resulting from the method may be made without holograms, DOVID, or the like
50. Product according to claim 36, characterised in that the products resulting from the method may be made starting from an uncoated polymer.

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