TAMPER-PROOF OBJECT

Description

Technical field

[0001] The present invention generally relates to the fields of object identification and authentication. More particularly, it relates to an anti-counterfeiting object that can be reliably authenticated. State of the art

[0002] Counterfeiting is a problem of ever-increasing magnitude. For businesses, counterfeiting is a nuisance because of its impact on sales, brand value and reputation, and its ability to take advantage of technical innovations. Consumers are also victims of counterfeiting, ending up with an inauthentic product despite the price they paid, and, in the case of products such as mechanical parts or medicines, posing significant safety and health risks. At the state level, counterfeiting is a concern for governments because of the threat it poses to consumer well-being and health, its negative impact on innovation, and the considerable resources devoted to criminal networks, organized crime, and other groups that disrupt and corrupt society.

[0003] Today, there are a multitude of technologies that can be used in the fight against counterfeiting. For example, nanotechnology and other advanced technologies are paving the way for new methods of brand protection and product tracking and tracing: they offer the potential for a unique "fingerprint" of the actual product (without affecting it), as well as the packaging. In this regard, the report "Nano and other Innovative Anti-Counterfeit Technologies" published by the Technology Transfer Centre in April 2016, describes more than 40 solutions, most of which were developed between 2014 and 2016.

[0004] Current technological options for combating counterfeiting include a range of so-called "overt" and "covert" measures that include product authentication and security. The anti-counterfeiting market can be primarily divided into two segments, namely authentication technologies (technologies providing overt and covert security features), and “Track & Trace Technologies” which are technologies that facilitate product visibility throughout the supply chain.

[0005] These technological options use serial numbers, barcodes, data systems, and RFID identifiers for identification, as well as holograms, biometric solutions, watermarks, and labels for security. These technologies have their own limitations at various levels and are not foolproof.

[0006] One of the particular challenges of anti-counterfeiting measures is the difficulty of preventing the copying of the RFID device, marker, hologram or any other authentication fingerprint.

[0007] US 2007 / 0121181 describes a method for marking and identifying an item based on X-ray diffraction (XRD) analysis. The method uses an identification element formed from powdered crystalline materials in a binder to provide an X-ray diffraction pattern representing the signature of the item when illuminated by an X-ray beam. The X-ray diffraction pattern represents a code, which is determined by the selection and omission of one or more of four different crystalline materials. This identification element can take various forms (beads, cylinders, fibers) and can be used for various purposes, such as sorting, tracking, identification, verification, authentication, anti-theft or anti-counterfeiting protection, security or counterterrorism, etc.

[0008] The proposed method is attractive because it allows for a large number of distinct codes and uses small objects. In addition, the XRD signature is readable regardless of orientation and can withstand harsh environments. Despite these advantages, the method described in US 2007 / 0121181 does not appear to be sufficiently secure. Indeed, X-ray diffraction is a conventional means of analyzing crystalline materials. It would be relatively easy for a person skilled in the art to analyze such an identifier to detect different crystalline materials and reproduce a compound with a very similar or identical diffractogram.

[0009] Other methods for authenticating objects are, for example, described in WO 2012 / 174232, US 2005 / 0112360, US 2007 / 0071951 or in the article "Anti-counterfeiting method using synthesized nanocrystalline cellulose markers", by Yu Ping Zhang, November 21, 2012, doctoral thesis, McGill University, Montreal.

[0010] WO2019 / 011986 presents an authentication method using X-ray crystallography, which is more secure than that described in US 2007 / 0121181. This method uses an authentication material that comprises at least one amorphous phase, at least one crystalline phase and at least one complex metallic phase. Indeed, such an authentication substance produces, by X-ray crystallography analysis, a unique diffraction pattern, forming a unique signature, or fingerprint, and its composition cannot be determined after manufacture of the substance. The strength of this approach lies in the impossibility of going back, by the analysis methods, to the manufacturing recipe of the authentication substance. Authentication is therefore done by comparison with a reference diffractogram.

[0011] In practice, a batch of the authentication substance is prepared and shaped, for example, into balls, cylinders, fibers, or into a label, badge, or other means of marking, which will be associated with an object for the purpose of authenticating it. It is also possible to incorporate the authentication substance into the object, by manufacturing the object entirely or partially in the authentication substance, or a component of the object is manufactured in the authentication substance.

[0012] It will then be possible to authenticate the object by analyzing the label made in the authentication material, or a part of the object made in the authentication material.

[0013] This method is very interesting because of its inviolable nature, due to the impossibility of going back, by the analysis methods, to the manufacturing recipe of the authentication substance. Nevertheless, it requires great rigor during the manufacturing of the batch, in order to maintain homogeneity in it, and therefore to guarantee an identical signature for all the products manufactured from the batch. In addition, the X-ray analysis method is by nature a covert method, and it is not always obvious that the object is an anti-counterfeiting object. Finally, it is necessary to maintain a database with the reference DRX signatures.

[0014] WO 2019 / 011986 does not describe the use of two filaments to construct the authentication volume. Subject of the invention

[0015] The object of the present invention is to propose an alternative concept of an anti-counterfeiting object which can be authenticated by X-ray diffraction, which does not have the aforementioned disadvantages. General description of the invention

[0016] According to a first aspect, the present invention provides an anti-counterfeiting object according to claim 1, comprising a face with an optical identification marking readable by eye and / or by a machine, as well as an authentication volume, the authentication volume extending from the surface of the object, from the same face or another face of the object, in the direction of the thickness of the object (or depth - relative to the face) so as to be accessible for reading by X-ray diffractometry (denoted DRX). The authentication volume comprises an immiscible mixture of a first material, called the authentication material, and at least one second material having its own DRX signature, different from that of the first material. The authentication material comprises: at least one amorphous phase, at least one crystalline phase and at least one complex metal phase.The authentication volume has a DRX signature resulting from the combination of emissions from the two materials. The authentication volume combines the first and second materials, in an immiscible manner, and results from the association, juxtaposition and / or superposition of the first and second materials, provided separately by additive construction using a filament of the authentication material and a filament of the second material. The identification marking indicates the authentication zone or includes information relating to the position of the authentication volume in the object.

[0017] The term "authentication volume" means a volume of the body of the object, which may take various forms, the body having an outer surface which includes the face bearing the identification marking and from which the authentication volume extends. The authentication volume may be located under the face bearing the identification marking, or under another face.

[0018] The authentication volume has a predetermined volume which is determined according to the sensitivity of the chosen DRX technique, and for a recording time between one or a few hours, up to one to two days. The authentication volume therefore represents a minimum volume of continuous material of the object which combines the first and the second material so as to allow detection by the chosen DRX method. Preferably, the predefined volume is at least 5 mm 3< , in particular at least 10 mm 3< .

[0019] The present invention complements anti-counterfeiting measures by proposing an approach that associates, with the object to be authenticated, an optical identification marking and an authentication volume. The identification zone is intended to be read by an optical reading means (generally automated), and is normally visible by looking at the object. While the identification zone is on the surface of the object, the authentication volume extends into the volume of the body of the object, and requires an X-ray analysis on a given volume of material.

[0020] As the authentication volume is not necessarily visible / discernible to the eye, and does not necessarily extend throughout the object, the authentication volume can be identified by a marking, which therefore indicates the authentication zone where the DRX analysis is to be carried out. This may be a specific marking, intended solely to identify the authentication zone. However, it is advantageous to position the identification and authentication zones close to each other (juxtaposition), and even to partially or completely superimpose them, in which case the identification marking also acts as an indicator marking of the authentication zone. In the case of superposition (at least partial), the measurement of the DRX signature is therefore carried out from the face bearing the identification marking.

[0021] It will be appreciated that the authentication is based on the combination of the authentication material with a second material, which generates a DRX signature resulting from the combination of the emissions of the two materials. The own signature of the second material is in fact combined with that of the first material, to give a composite DRX signature, a function of the distribution of the authentication material in the analyzed authentication volume, in particular its quantity and its spatial position (in x, y and z). Indeed, DRX analysis being sensitive over a certain depth (typically of the order of a millimeter), it is possible to play on the distribution along the Z axis (depth) to define and modulate the DRX signature of the authentication volume.

[0022] The object according to the invention therefore constitutes an object which can be described as “anti-counterfeiting” in relation to its use, and which is itself “anti-copy”, because it cannot be reproduced.

[0023] Preferably, the authentication volume extends from the face with the identification marking to a depth of between 0 and 1.5 mm, preferably between 0 and 1 mm, more preferably between 0 and 600 µm, or even 0 to 400 µm.

[0024] The authentication material may be present on the surface and / or distributed in depth.

[0025] According to variants, the authentication volume extends over a surface, taken in a plane substantially parallel to said face of the object, of at least 10 mm 2< , preferably at least 100 mm 2< .

[0026] For ease of language, in this text, the term "matter" is used as a synonym for material.

[0027] In this text, the term "XRD signature" refers to at least a part of the diffractogram (X-ray diffraction pattern) corresponding to a given sample (reference or candidate), and which contains the characteristic values of the XRD analysis. The XRD signature can, in general, be represented graphically or as a set of data. Furthermore, authentication can be done on the entire diffractogram, or on one or more parts of it. In practice, the XRD signature comprises a set of characteristic pairs of the diffractogram (angle; intensity), representative of the analyzed sample.

[0028] Identification marking can take a variety of forms, can be readable under visible light or under predefined light (e.g. infrared). Identification marking can include numbers and / or letters, representing a code or not, or any type of index representing a code, e.g. bars, dots, circles, squares, etc. In particular, one can use one- or two-dimensional codes, codes of the type: bar code, QR code, matrix code, circular code (e.g. "bleam" type), etc. Identification marking represents information that can be of different natures, in particular information relating to the nature of the object, for example its name, manufacturer reference, regulatory data, etc., as well as their combinations.

[0029] Depending on the variant, the optical identification marking is made from both materials, each having a different color.

[0030] Depending on the variant, the identification marking is a two-color matrix marking, a surface layer being made from the first and second material, each having a different color.

[0031] Depending on the variants, the identification marking comprises a series of marks representing a code delimited by a peripheral line, the authentication volume being located within the outline of this peripheral line.

[0032] Object authentication is performed by comparing the measured DRX signature with a reference DRX signature, either automatically or with assistance, based on graphs and / or numerical values. In general, measured and reference DRX signatures are considered to match when the angular positions and intensities are identical or similar (within a defined tolerance threshold). Thus, the comparison of DRX signatures mainly involves a comparison of the angular positions of the characteristic / representative peaks and / or a comparison of the relative intensities of the characteristic / representative peaks.

[0033] The reference DRX signature can be stored, e.g., in a database, locally or online. It is of course possible to keep a control sample, from which the reference DRX signature can be measured.

[0034] Remarkably, the optical identification marking may include information relating to the DRX signature that is to be obtained when the authentication volume is subjected to DRX analysis. The authenticity of the object is then verified by comparing the DRX signature measured for the authentication volume with the DRX signature encoded in the information marking.

[0035] An important advantage of this approach is therefore that a reference DRX signature is encoded in the identification marking, and there is no need to access or even maintain an online database to obtain the reference DRX signature.

[0036] It should be noted here that in the case where the authentication volume is spaced from the identification marking, for example if the authentication volume is located on a face other than the face bearing the identification marking, it is possible to encode in the identification marking information relating to the position of the authentication volume in the object, therefore for example measurement coordinates for carrying out the DRX analysis, indicating the location of the measurement zone.

[0037] Furthermore, while the use of DRX falls under the so-called covert methods of combating counterfeiting (as in WO 2019 / 011986), the present invention proposes an approach combining optical identification and DRX authentication, in which the authentication zone is preferably marked so that it is known where to carry out the DRX measurement. This is therefore particularly interesting because the quantity of authentication material can be reduced to that necessary for authentication.

[0038] It is recalled that the authentication material used in the invention, similar to that described in WO2019 / 011986, produces a unique X-ray diffractogram, constituting a unique signature. Its composition cannot be determined after manufacture. Current analysis techniques do not allow the qualitative and quantitative analysis of the individual materials constituting the authentication material. In particular, chemical analysis does not allow the deciphering of a composition to which a given diffractogram corresponds. Elemental analysis is carried out without distinction of the different crystalline structures and phases present. XRD analysis is also unable to determine the composition of the authentication material, as it does not provide access to the volume fractions of the different phases.

[0039] Due to the phenomenon of X-ray absorption and the overlapping of diffraction peaks of different crystalline and complex phases of metal alloys, it is impossible to accurately determine the volume fractions of the different phases included in the authentication volume.

[0040] The invention also allows for a material saving, because, unlike WO 2019 / 011986, the DRX signature results from a combination between the authentication material and the second material, which can be any and above all does not contain the specific combination of phases of the authentication material. The second material can therefore be less expensive both in terms of purchase cost and its implementation. This is particularly interesting because the composite DRX signature can be varied by varying the ratio between the two materials. In some variants the second material is present in a predominant manner, forming in some cases a matrix, but in other variants there may be a preponderance of the authentication material.

[0041] In principle, the second material can be any material, polymer, wood, fiber, metal, etc. Generally, the second material has its own DRX signature which is different from that of the authentication material. The second material is preferably polymer-based, for example single or two-component, filled composite, elastomer, silicone, etc. The second material could itself be an anti-copy material. The invention can also be implemented with more than one second material, respecting the same DRX signature criterion different from the authentication material.

[0042] The respective volumes and spatial arrangements (in the authentication volume) of the first and second materials can be varied by design, depending on the signatures that one wishes to construct. One can have between 1 and 99% of authentication material in the authentication volume, the remainder being completed by the first material. The authentication volume preferably contains at least 10% of authentication material.

[0043] The shape of the object is limited only by the minimum volume required for DRX analysis. It can take all kinds of shapes. It is possible to manufacture large objects. But the invention is particularly well suited to the production of the object in the form of a label, plate, stamp, strip, panel, vignette, stamp, badge, etc.

[0044] The object may be designed so that the authentication volume is present, uniformly, throughout its entire volume, or only on a part of it. In the latter case, the authentication volume is contiguous with, and / or (partially) superimposed with, the identification zone. By superimposed, it is meant here that the authentication volume, seen in the direction of the thickness, is located at least partially below the identification zone (respectively the signs of the identification marking).

[0045] Depending on the variant, the optical identification marking and the authentication volume overlap at least partially (seen in the thickness direction).

[0046] In some applications, the authentication volume can be attached to / in a support part, the assembly of the two forming the anti-counterfeiting object.

[0047] The anti-counterfeiting object according to the invention can be manufactured by any suitable technology.

[0048] In general, the first and second materials are prepared independently of each other. They are then combined to produce a whole part or part of a part, and therefore in particular to form the authentication volume. The first and second materials are thus combined in the authentication volume, by associating and / or juxtaposing and / or superimposing them, in order to obtain a spatial distribution within the volume. This spatial distribution determines the composite signature of the authentication volume.

[0049] The first and second materials are brought independently simultaneously or successively to form this combination in the authentication volume (with a given spatial distribution), by additive construction from two different threads, one with the first material and the other with the second material.

[0050] Additive manufacturing techniques are particularly attractive for their flexibility and ease of implementation. In addition, they allow for very precise control of material deposition, and therefore allow for layer-by-layer control of material deposition. 3D printing therefore allows for the combination of the authentication material and the second material (or other materials) to be controlled as desired, both in the plane of the layer and in depth. The fused deposition modeling (FDM) technique is particularly interesting to implement with two (or more) different filaments, one of which contains the authentication material.

[0051] In this respect, it should be noted that it is possible to manufacture threads of authentication material with very good homogeneity.

[0052] According to the variants, the object consists of a plurality of superimposed layers formed by 3D printing, at least one of the layers located at a depth between 0 and 0.6 mm from the surface comprising at least in part authentication material.

[0053] As is clear to those skilled in the art, similar X-ray characterization techniques (in particular the same X-ray sources) will advantageously be used in order to be able to compare the diffractograms of different objects.

[0054] In this text, the term "amorphous phase" is used in its conventional sense, generally referring to non-periodic three-dimensional structural arrangements, lacking the long-range regularity characteristic of crystals. Typically, in an amorphous phase, X-rays will be scattered in a plurality of directions, resulting in broad, ill-defined peaks.

[0055] In this text, the term "crystalline phase" is used in its conventional sense in crystallography, designating a crystalline structure, that is to say an ordered arrangement of atoms, ions, molecules, forming a symmetrical pattern which is periodically repeated according to the principal directions of the three-dimensional space of matter. In this text, the term "crystalline phase" thus covers the historical definition of crystals but does not cover "quasi-crystals" or more generally "complex metal alloys", defined below. Crystalline phases have a diffractogram characterized by a set of discrete and intense peaks.

[0056] In this text, the term "complex metal alloy" means an alloy which is either a quasi-crystalline phase in the strict sense or an approximate phase. Quasi-crystalline phases in the strict sense are phases having rotational symmetries normally incompatible with translational symmetry, i.e. rotation axis symmetries of order 5, 8, 10 or 12. Examples include the icosahedral phase having icosahedral group symmetry and the decagonal phase having decagonal group symmetry.

[0057] Approximate phases or approximate compounds are true crystals insofar as their crystallographic structure remains compatible with translational symmetry, but which present, in the electron diffraction pattern, diffraction patterns whose symmetry is close to a symmetry of order 5, 8, 10 or 12. These are phases characterized by an elementary mesh containing several tens, even several hundreds of atoms, and whose local order presents arrangements of almost icosahedral or decagonal symmetry similar to the parent quasi-crystalline phases. Complex metallic phases have a powder diffractogram characterized by a dense set of discrete and intense peaks, clearly more complex than conventional metallic alloys.

[0058] Among these phases, we can cite as an example the orthorhombic phase O 1 characteristic of an alloy having the atomic composition Al 65 Cu 20 Fe 10 Cr 5 , whose lattice parameters in nm are: a 0 (1) < =2.366, b 0 (1) < =1.267, c 0 (1) < =3.252. This orthorhombic phase O 1 is said to be an approximation of the decagonal phase. The nature of the two phases can be identified by transmission electron microscopy.

[0059] We can also cite the rhombohedral phase with parameters a R = 3.208 nm, α = 36°, present in alloys with atomic composition close to Al 64 Cu 24 Fe 12 . This phase is an approximate phase of the icosahedral phase.

[0060] We can also cite orthorhombic O 2 and O 3 phases with respective parameters in nm a 0 (2) < =3.83, b 0 (2) < =0.41, c 0 (2) < =5.26; and a 0 (3) < =3.25, b 0 (3) < =0.41, c 0 (3) < =9.8, present in an alloy with atomic composition Al 63 Cu 17.5 CO 17.5 Si 2 ; or the orthorhombic O 4 phase with parameters in nm a 0 (4) < =1.46, b 0 (4) < =1.23, c 0 (4) < =1.24, which forms in the alloy with the atomic composition Al 63 Cu 8 Fe 12 Cr 17 .

[0061] We can also cite a C phase, with a cubic structure, very often observed in coexistence with the approximate or true quasi-crystalline phases. This phase, which forms in certain Al-Cu-Fe and Al-Cu-Fe-Cr alloys, consists of a superstructure, by chemical order effect of the alloying elements with respect to the aluminum sites, of a phase with a Cs-CI type structure and a lattice parameter a 1 = 0.297 nm. A diffraction diagram of this cubic phase has been published for a sample of pure cubic phase and atomic composition Al 65 Cu 20 Fe 15 in number of atoms.

[0062] We can also cite a hexagonal H phase which derives directly from the C phase as demonstrated by the epitaxy relationships observed by electron microscopy between crystals of the C and H phases and the simple relationships which link the parameters of the crystal lattices, namely aH=3√a1 / √3 (to within 4.5%) and cH=3√2·a 1 / 2 (to within 2.5%). This phase is isotype of a hexagonal phase, noted ΦAlMn, discovered in Al-Mn alloys containing 40% by weight of Mn.

[0063] The cubic phase, its superstructures and the phases derived from it, constitute a class of phases approximating quasi-crystalline phases of similar compositions.

[0064] Quasi-crystalline alloys of the Al-Cu-Fe system are also suitable for implementing the present invention. In particular, alloys which have one of the following atomic compositions may be mentioned: Al 62 Cu 25.5 Fe 12.5 , Al 59 Cu 25.5 Fe 12.5 B 3 , Al 71 Cu 9.7 Fe 8.7 Cr 10.6 , and Al 71.3 Fe 8.1 Co 12.8 Cr 7.8 . These alloys are, for example, marketed by the company Saint-Gobain (or Sigma-Aldrich). In particular, the alloy Al 59 Cu 25.5 Fe 12.5 B 3 is marketed under the name Cristome F1, the alloy Al 71 Cu 9.7 Fe 8.7 Cr 10.6 is marketed under the name Cristome A1, and the alloy Al 71.3 Fe 8.1 Co 12.8 Cr 7.8 is marketed under the name Cristome BT1.

[0065] Cristome A1, F1 and BT1 alloys are cited as examples only.

[0066] The complex metal alloys that can be used in the context of the invention may be metal alloys comprising an atomic percentage of aluminum greater than 50%.

[0067] According to another aspect, the invention relates to a method for manufacturing an anti-counterfeiting object, in which said object is produced by additive construction using: a filament of authentication material comprising at least one amorphous phase, at least one crystalline phase and at least one complex metallic phase; and at least one polymer-based filament of a different color. The manufacturing is carried out by printing successive superimposed layers. The surface layer is printed so as to form an identification marking.The method is implemented such that the material of the authentication material filament is deposited in the surface layer and / or in one or more layers below the surface layer so as to form an authentication volume, such that the authentication volume has a DRX signature resulting from the combination of the emissions of the two materials, wherein the identification marking indicates the authentication area or comprises information relating to the position of the authentication volume in the object.

[0068] According to another aspect, the invention relates to a method for authenticating an anti-counterfeiting object as disclosed in the present application, comprising the following steps: reading the identification marking of the anti-counterfeiting object by a reading instrument in order to obtain information; analysis by X-ray diffraction, DRX, of the authentication zone of the anti-counterfeiting object in order to determine its DRX signature; and comparison of the DRX signature of the anti-counterfeiting object with a reference DRX signature.

[0069] The identification marking typically takes the form of a one- or two-dimensional code. Its reading is advantageously done automatically using a reader.

[0070] Comparison of DRX signatures is preferably computer-assisted.

[0071] The reference DRX signature can be obtained by accessing a file or database locally or online. In this case, the identification marking can include the address, URL or hyperlink allowing access to the DRX signature.

[0072] Alternatively, information relating to the reference DRX signature can be encoded in the identification marking. This is information relating to the diffractogram corresponding to the reference DRX signature, for example characteristic peaks identified by the pairs (angle, intensity), possibly supplemented by the indication of the wavelength of the X-ray source.

[0073] According to yet another aspect, the invention relates to a method of manufacturing an anti-counterfeiting object according to claim 14. Detailed description using figures

[0074] Other features and characteristics of the invention will emerge from the detailed description of at least one advantageous embodiment presented below, by way of illustration, with reference to the appended drawings. These show: [ Fig. 1 ]: an XRD diffractogram corresponding to example 1; [ Fig. 2]: a view of two identical QR codes according to example 2-A; [ Fig. 3 ]: an XRD diffractogram corresponding to example 2-A; [ Fig. 4 ]: a view of two QR codes according to example 2-B; [ Fig. 5 ]: an XRD diffractogram corresponding to example 2-B; [ Fig. 6 ]: a view of two QR codes according to example 3-A; [ Fig. 7 ]: an XRD diffractogram corresponding to example 3-A; [ Fig. 8 ]: an XRD diffractogram corresponding to example 3-B; [ Fig. 9 ]: an XRD diffractogram corresponding to example 4; [ Fig. 10 ]: an embodiment of the invention in the form of a QR code label; [ Fig. 11 ]: an embodiment of the invention in the form of a label bearing a bar code; [ Fig. 12 ]: an embodiment of the invention in the form of a label; and [ Fig. 13 ]: an embodiment of the invention in the form of a pawn carrying a circular code; [ Fig. 14]: an XRD diffractogram corresponding to example 5. A) Examples

[0075] Several examples have been produced to illustrate the principle of the invention. Examples 1 to 3 use labels or pads with a QR code type pattern. These pads are produced using a conventional FDM type 3D printer and using two filaments with a diameter of 1.75 mm. One of the filaments is the authentication material (material comprising at least one amorphous phase, at least one crystalline phase and at least one complex metallic phase) and the other filament is polymer-based which has its own DRX signature different from the other filament, for example PLA (polylactic acid).

[0076] DRX measurements were performed on a Bruker D8 Advance device, in theta / 2theta Bragg Brentano configuration, with a copper anode X-ray tube. The measurement was performed over an angular range of 15 to 90°, with a measurement step of 0.018627795°, for a total scan time of 55min 50s. • Example 1

[0077] For this example, the aim is to produce, by filament deposition modeling (FDM), samples in the form of "pellets" 1 mm thick and 25 mm in diameter, i.e. 10 successive layers of 100 µm thickness. For this, two wires are used, corresponding to two different materials: one is the authentication material, the other is a conventional PLA. The authentication material filament here comprises: 50 μm% of an amorphous phase given by the PLA, 25 μm% of a crystalline phase, and 25 μm% of a mixture of quasicrystalline icosahedral phase and an approximant phase. The approximant and complex alloys are alloys of the Al-Cu-Fe system with the appropriate addition elements (chromium or boron, as explained above).

[0078] A first control sample is produced, consisting of 10 layers of PLA.

[0079] Then 9 other samples are produced, in which 9 layers of PLA are deposited, as well as a single layer consisting of 100% authentication material. For these 9 samples previously described, the position of the layer of 100% authentication material is varied, from the first layer (top layer of the pellet), to the tenth and last layer (bottom layer of the pellet). All the samples are then analyzed (analysis from the top face) by DRX method to obtain their characteristic signature.

[0080] There Figure 1represents the diffractogram obtained for the control sample ct and samples c1 to c4 whose authentication layer is located respectively at depths 0-100 µm, 100-200 µm, 200-300 µm and 300-400 µm. As can be observed, the DRX signatures of samples c1 to c4 - resulting from the coupling of authentication material and PLA - are different from each other, and different from the signature of the control sample ct.

[0081] Thus, the analyses reveal that changing the position of the authentication material layer modifies the signature obtained up to approximately 600 µm, i.e. up to the 6th layer. Beyond this depth, the signature of a composite pellet becomes very close or identical to that of the control pellet. It can therefore be considered that the composite signature can be effectively measured up to 600 µm, which represents a limit of detectability for the chosen DRX analysis conditions.

[0082] This first example allows us to conclude that DRX signatures can be controlled in an object depending on the position of the authentication material along the Z axis, and therefore depending on the depth. • Example 2

[0083] This example aims to study the repeatability of the authentication measurement. A QR code is generated, comprising two colors, and printed using PLA filament for one color and authentication filament for the other. Thus, we have a black and light gray QR code, the black corresponding to the authentication filament and the light gray to the PLA filament. i) Manipulation 2-A. Two QR codes are printed that are identical in terms of pattern and filaments used. They are shown in Fig.2 The DRX signatures obtained after analysis are identical, cf. Fig. 3These results confirm that for the same pattern, with the same distribution of materials, the same authentication signature is obtained. The signatures are therefore reproducible for an identical identification zone. ii) Manipulation 2-B. In a second step, we always keep the same pattern, and we reverse its colors. We print a second QR code, but the light gray takes the place of the black and vice versa, as illustrated in Fig.4 The signatures obtained turn out to be very close and difficult to discern, cf. Fig.5 . In fact, when the distribution of the two colors is similar, for example 50 / 50 surface distribution, we have the same concentration of the two materials before and after reversing the colors.

[0084] It is therefore possible to create two different patterns but with similar material distributions (colors), and therefore to have two identical DRX signatures for two different identification information.

[0085] It can therefore be concluded that DRX signatures are reproducible for a different identification zone. • Example 3

[0086] This example demonstrates the possibility of modifying the signature while keeping the same identification pattern. i) Manipulation 3-A. We repeat the first manipulation (2-A) of example 2 by varying the PLA filament used, changing color and opacity (example: red instead of light gray). Black is therefore made with the authentication material filament. The QR codes are shown Fig.6 . For two QR codes with the same pattern, therefore encoding the same information, we obtain two different signatures, see Fig.7 . So for the same identification information, the authentication changes: the DRX signatures are different for an identical identification zone. ii) Manipulation 3-B.Next, we print two QR code pads with the first layer identical (same pattern, same materials, etc.). This time, we only work on the lower layers to modify the volumetric authentication information while keeping the same identification information (because of the same surface pattern). The composition of each layer is indicated in the table below; it is noted that layers 2, 3 and 4 are different between the two manufactured pads.

[0087] The diffractogram of the two pellets is shown in Fig. 8 As you can see, the signatures are different for the same identification zone. This example therefore demonstrates the possibility of modifying the DRX signature for the same identification information. [Table 1] 1 2 Layer 1 MA = Authentication Material {Polymer+CMAs} + PLA Layer 2 MY PLA Layer 3 MY PLA Layer 4 MY PLA Example 4

[0088] Unlike the previous examples, this example does not use 3D printing but screen printing (ink deposition). It is not part of the claimed invention, but may be useful for understanding it.

[0089] A mixture of screen printing ink {active material (Ag, C, dielectric powder, etc.) + epoxy, acrylic, polyimide or phenolic resins} and authentication material additives / powders is made. A mask is then made from a PET sheet (thickness -130 µm) from which the desired pattern (e.g., a disc) is cut using a laser cutting machine. The substrate subsequently used for screen printing is of the same nature as the mask: a PET sheet of approximately 130 µm.

[0090] After producing our object by screen printing, we obtain an authentication deposit of approximately 130 µm on a PET substrate. This multi-layer sample (PET / Authentication deposit) has a unique DRX signature.

[0091] Three materials were analyzed, including one prepared according to this protocol: a1: complex metal alloy 1, in powder form a2: complex metal alloy 2, in powder form s: sample prepared by screen printing, with a PET substrate and an ink containing authentication powder, both of which constitute a1 and a2 (two complex metal alloys)

[0092] The diffractogram of each of the samples is represented in Fig.9 .

[0093] DRX analysis of the sample produced by screen printing makes it possible to detect a DRX signature allowing authentication of the sample. Example 5

[0094] This example aims to determine the separation threshold of two identification patterns.

[0095] For this example, we are basing ourselves on an area analyzed during a DRX analysis of 1 cm 2< , as well as on the limiting resolution of a basic FDM printer equipped with a 0.4mm diameter nozzle: order of magnitude of 1mm. Thus, we produce blocks of 1cm 2< and 1mm thickness, gridded using 100 small cubes of 1mm 3< .

[0096] The objective is to verify the threshold, in terms of volume (therefore cubes of 1mm 3< ), from which the signature is modified sufficiently to be detected with the present DRX analysis equipment.

[0097] We then make different blocks, one with 100% cubes printed using PLA filament, one with 100% cubes printed using authentication filament and then a block with 50 cubes in PLA and 50 in authentication material (AM). Finally, from this last 50 / 50 block, we make 4 other blocks where we vary this distribution by modifying the composition of one or two cubes (e.g.: 51 cubes in PLA and 49 in authentication material, so 1 cube has gone from the composition of the authentication material to PLA).

[0098] After DRX analysis, it appears that modifying the composition of 1 to 4 cubes out of 100 cubes (i.e. 1 to 4% volume variation in composition) does not allow separable DRX signatures to be obtained.

[0099] So, the same protocol is repeated, this time increasing the step. The blocks are the same size, but they are gridded into 5x5 cubes of 4mm 3< , or blocks of 25 cubes. When the composition of a single cube is changed, this represents a 4% volume variation in composition.

[0100] DRX analyses reveal that a step of 2 cubes of 4mm 3< , or 8% volume variation in composition, makes it possible to obtain two different signatures. This discretization threshold is well illustrated in Figure 14 , which represents the diffractograms for the different blocks produced, namely: q0=100% PLA, q1=42% MA, q2=46% MA, q3=50% MA, q4=54% MA, q5=58% MA, and q6=100% MA As we can clearly see, a difference of 8% by volume for the authentication material is sufficient to differentiate the DRX signatures (e.g. between q3 and q5). B) Methods of implementation

[0101] The operating principle of the invention having been demonstrated on the basis of the preceding examples, we will now describe, using the figures 10 to 13 , several possibilities for producing this anti-counterfeiting object, here in the form of pellets, which can also be called a plate or label.

[0102] Each of the objects 10, 30, 50 and 70 comprises a face 12, 32, 52 and 72 which carries an identification zone having an identification marking 14, 34, 54 and 74. All the identification markings are here visible to the naked eye, under normal conditions. The face 12, 32, 52 and 72 extends in the examples in a plane parallel to (x,y), and the direction of the thickness is therefore that of the z axis, typically perpendicular to (x,y).

[0103] Each object comprises an authentication volume extending from the face 12, 32, 52 and 72 in the thickness direction (along the z axis) so as to be accessible for reading by X-ray diffractometry, DRX. The authentication volume is a composite of a first material, called authentication material, and at least one second material. The authentication material comprises at least one amorphous phase, at least one crystalline phase and at least one complex metal phase.

[0104] The authentication material has a DRX signature which is unforgeable because the use of complex metallic phases makes qualitative and quantitative analysis impossible.

[0105] The second material is used to obtain a composite signature, resulting from the combination of the two materials in the analysis volume, and therefore different from that of the DRX signature of the first material alone.

[0106] The authentication volume is thus a composite volume of the first and second materials. Both materials are present in this volume, but the first and second materials are not miscible. The authentication volume therefore includes volumes of the first and second materials.

[0107] As understood from the figures, the authentication volume is associated with the identification marking. The identification marking constitutes a visible surface marking, whereas the authentication volume is a non-visible marking that extends into the volume. Generally, the authentication volume is placed near or at least partially overlaps the identification marking (viewed in the z direction).

[0108] An operator who knows the construction of this type of object knows that he can authenticate the object by analyzing the authentication volume by DRX analysis at the level of an area to be attacked from the surface 12, and which is located near the marking area or overlaps with it (partially or totally).

[0109] Conventional 3D printing technology of the FDM type (fused deposition modeling) is particularly interesting because it allows the material combination to be controlled by using, according to the claimed invention, a thread of the authentication material and a thread of the second material, e.g. polymer-based. The resolution of conventional 3D printing will allow deposits in layers or strata, by choosing the positioning of the materials both in the plane (X,Y) and in the thickness (Z) of the object. The distribution of material is therefore entirely controlled in the authentication volume, with good precision, which allows excellent reproducibility of the construction. Control of the deposition will also allow different constructions of the authentication volume to be controlled (ratios and positions in XYZ).

[0110] It has been represented on the Fig. 10a reference (X, Y, Z), the layers are parallel to the X, Y plane, and stacked along the Z axis (this is therefore the thickness axis). The thickness of a layer is for example around 100 µm, but can typically vary between 20 and 300 µm with conventional printers.

[0111] The object of the figure 10is a QR code disc, which has a parallelepiped body. The surface layer is obtained by printing with two PLA threads of different colors, in order to form the desired QR code. The surface layer C1 rests on a plurality of printed layers C2 to Cn in PLA, except for one layer, e.g. C4, which is printed entirely with the authentication material. We therefore have a layer of authentication material which extends to a given distance below the surface, however within the DRX detection limit (preferably < 600 µm). During DRX analysis by the surface 12, a composite DRX signature resulting from the combination of PLA and the authentication material is obtained, over the detection / penetration depth.

[0112] The authentication layer here is 100% authentication material, but there can be less, in combination with PLA or another printable polymer. Generally speaking, we can have authentication material in one or more layers, from C1 up to layer Ci located at the detection limit. Indeed, in practice we can play on the presence of authentication material in several layers, to multiply the number of signatures. Layer C1 can also be made with a thread of authentication material and a polymer-based thread of a different color.

[0113] The object of the Fig. 11 is a simple label (flat and oval body) with a 34 identification marking that is readable by eye and simply indicates a text, which can be the brand of a product or service, or the name of a company. This label is manufactured by 3D printing with the same materials as for the disc of the Fig. 10, and a 100% layer of authentication material was integrated at a given depth, within the detection limit of the DRX analysis. The layer of identification material has the same surface area as face 34. The DRX analysis can therefore be carried out at any location on face 32, to obtain the DRX signature of the object.

[0114] In another embodiment, which is not part of the claimed invention, the label can be made of a conventional plastic material (or other materials: wood, leather, fabric, etc.), by printing or not, e.g. PET, PLA, ABS, PA, HDPE, etc., i.e. not incorporating an internal layer of authentication material. The reference sign 36 designates a circular cavity with a diameter of approximately 10 to 20 mm and a depth of 100 to 200 µm filled with an ink deposited by screen printing, indicated 38. The ink is, as for example 4 above, a mixture of the compounds of the ink itself, and powders of authentication material. The DRX signature of the object can therefore be determined by DRX analysis at the level of the ink deposit 38. The DRX signature is a composite signature resulting from the materials present, in particular the ink with the ink compounds and the authentication material powders, and the underlying support.

[0115] In the variant of the Fig. 12 , a label 50 (parallel piped body) was produced by 3D printing which comprises on its face 52 an identification zone having an identification marking 54 of the linear barcode type. During manufacturing, the authentication material was deposited, at a given depth, on a portion of the surface 52 of the label 50. More precisely, the authentication material is deposited next to the barcode 54, here at a longitudinal end, in particular to the left of the broken line 56 (virtual line).

[0116] The label thus comprises an identification marking 54, and an authentication zone 58 (symbolically represented by the discontinuous rectangle) separate from but adjacent to the identification zone 54. The line 56 or the frame 58 could be drawn on the face 52 to indicate to the operator where to carry out the DRX analysis.

[0117] The method of realization of the Fig. 13is made on the same principle as the label of the Fig. 10 . This is a disc-shaped PLA printed pin 70. The surface layer includes a circular two-dimensional code 74 of the "bleam" type made with two different PLA threads. A layer with 100% authentication material is placed at a predetermined depth to allow DRX analysis. DRX analysis can therefore be carried out at any location on the face 72 of the pin 70. The code 74 extends only over a portion of the surface layer. The authentication and identification areas are therefore partially superimposed.

[0118] The identification marking represents information which may be of different natures, in particular one or more of the following information: nature of the object, name, manufacturer's reference, regulatory data, and information relating to the DRX signature.

[0119] Regarding the DRX signature information, a link to a file or database containing the reference DRX signature can be included. Alternatively, the reference DRX signature, i.e., information representing the characteristic peaks (angle, intensity), can be encoded directly in the identification marking.

[0120] The results presented above, and in particular the diffractograms, were obtained with a given X-ray characterization technique, presented above, in particular with a copper Rx source. It is clear to the person skilled in the art that, depending on the materials / composites analyzed, the diffractogram may vary depending on the wavelength of the incident X-ray radiation. In order to be able to compare diffractograms, it will therefore be ensured that similar X-ray characterization techniques are used, in particular with the same Rx source (same wavelength). Where appropriate, the information relating to the reference DRX signature may include the wavelength and / or the type of Rx source to be used.

Claims

1. An anti-counterfeiting object, comprising: a side (12) with an optical identification marking (14) which is readable by the eye and / or by a machine, and an authentication volume, said authentication volume extending from said side (12), or from another side of the object, in the thickness (z) direction so as to be accessible from this side in order to be read by x-ray diffractometry, XRD; wherein the authentication volume is a composite of a first material, referred to as the authentication material, and at least one second material, the authentication volume constituting a material volume of at least 5 mm3, the authentication volume having an XRD signature resulting from the combination of emissions from the two materials; and the authentication material comprises at least one amorphous phase, at least one crystalline phase and at least one complex metal phase; wherein the second material has its own XRD signature, different from that of the first material; wherein the authentication volume combines the first and second materials, in a non-miscible manner, and results from the association, juxtaposition and / or superposition of the first and second materials, added separately by additive construction using a filament of the authentication material and a filament of the second material; and wherein the identification marking (14) indicates the authentication area or comprises information relative to the position of the authentication volume within the object.

2. The object according to one of the preceding claims, wherein the authentication material is present on the surface and / or distributed in the thickness.

3. The object according to one of the preceding claims, wherein the authentication material is present, in the authentication volume, at a given depth, or at several depths relative to the surface.

4. The object according to one of the preceding claims, wherein the authentication material occupies a volume of at least 10 mm3.

5. The object according to one of the preceding claims, wherein the authentication volume extends from said side to a depth between 0 and 1.5 mm, preferably between 0 and 1 mm, more preferably between 0 and 0.6 mm, in particular between 0 and 0.4 mm, and / or wherein the authentication volume extends over a surface, taken in a plane substantially parallel to said side of the object, of at least 10 mm2, preferably at least 100 mm2.

6. The object according to one of claims 1 to 4, wherein, seen in the direction of the thickness, the optical identification marking and the authentication volume are superimposed at least partially, for reading from said side (12), or wherein the identification marking comprises a series of marks that are representative of a code delimited by a peripheral line, the authentication volume being located inside the contour of this peripheral line.

7. The object according to one of claims 1 to 4, wherein the optical identification marking is done from two materials, each having a different color, or wherein the identification marking is a two-color matrix marking, a surface layer being made from the first and the second material, each having a different color.

8. The object according to one of claims 1 to 4, wherein the object is made up of a plurality of superimposed layers formed by 3D printing, at least one of the layers located at a depth between 0 and 0.6 mm from the surface comprising at least part of the authentication material.

9. The object according to one of claims 1 to 4, wherein the optical identification marking comprises measurement coordinates to perform the XRD analysis, indicating the location of the measurement area.

10. A method for manufacturing an anti-counterfeiting object according to claim 1, wherein said object is made by additive construction using a filament of authentication material comprising at least one amorphous phase, at least one crystalline phase and at least one complex metal phase, and at least one polymer-based filament of a different color, wherein said object is formed by successive printing of a plurality of layers, a surface layer being printed so as to form an identification marking and the material of the filament of authentication material being deposited in the surface layer and / or in one or a plurality of layers below the surface layer so as to form an authentication volume, such that the authentication volume has an XRD signature resulting from the combination of emissions from two materials, wherein the identification marking indicates the authentication area or comprises information relative to the position of the authentication volume within the object.

11. A method for authenticating an anti-counterfeiting object according to one of claims 1 to 5, comprising: reading the identification marking of the anti-counterfeiting object using a reading instrument in order to obtain information; analyzing, by x-ray diffractometry, XRD, the authentication area of the anti-counterfeiting object in order to determine its XRD signature; comparing the XRD signature of the anti-counterfeiting object with a reference XRD signature.

12. The method according to claim 11, wherein said identification marking comprises information relative to said reference XRD signature, in particular regarding the positions and intensities of the characteristic peaks.

13. The method according to claim 11, wherein said reference XRD signature is obtained from a database.

14. A method for manufacturing an anti-counterfeiting object, wherein at least part of the object is manufactured by mixing, in a non-miscible manner, a first material, referred to as authentication material, and at least one second material so as to form an authentication volume, said authentication volume extending from a side of the object in the thickness (z) direction so as to be accessible from this side in order to be read by x-ray diffractometry, XRD, the authentication volume having an XRD signature resulting from the combination of the emissions of the two materials, and the object also includes, on this side or another side, an optical identification marking (14) that is readable by the eye and / or by a machine; said optical identification marking indicating the authentication area or comprising information relative to the position of the authentication volume within the object; and the authentication material comprises at least one amorphous phase, at least one crystalline phase and at least one complex metal phase; wherein the first and second materials are added separately by additive construction using a filament of the authentication material and a filament of the second material to form the authentication volume, in which they are associated, juxtaposed and / or superimposed.