HK1237135B - Anti-counterfeiting tag maintaining a functionality after use - Google Patents

Description

Anti-counterfeiting label that retains function after use

Technical Field

The present invention relates to near-field magnetically coupled contactless identification devices, such as NFC, ISO 14443 or ISO 15693 devices, and more particularly to anti-counterfeiting contactless devices for ensuring the authenticity of the contents of a bottle.

Background Art

US Patent 7,898,422 describes an anti-counterfeiting NFC device integrated into a wine bottle cork. The device is designed so that insertion of a bottle opener damages the antenna or the control microcircuitry.

When the device is complete, it can be remotely interrogated by an NFC reader to retrieve the information on the product and also confirm the authenticity of the information. When the cork has been removed, the NFC device is destroyed, so the cork can no longer be used to authenticate the contents of a new bottle.

For example, U.S. Patent Application 2005-0012616 discloses an RFID tag with a sacrificial antenna designed to be destroyed when a container is opened. The sacrificial antenna enables reading the tag at an extended distance range. When the sacrificial antenna is destroyed, the tag can continue to operate in a no-antenna mode with a limited read distance range.

U.S. Patent Application 2007-0210173 describes an RFID tag with two parts, each containing a separate RFID component with encryption capabilities. A ruptured tag renders one of the two RFID components inoperable. If a reader can negotiate authentication with both RFID components of the tag, the reader is programmed to signal that the tag is intact. If only one authentication is negotiated, the tag is considered compromised.

Summary of the Invention

Generally, a near-field magnetically coupled anti-counterfeiting label is provided, comprising: a control microcircuit configured to implement basic functions and encryption functions; a sacrificial conductive track arranged across a sacrificial area of the label; and a circuit for detecting the continuity of the sacrificial track, which cooperates with the microcircuit to implement the basic function without implementing the encryption function when the sacrificial track is destroyed.

The microcircuit may be a standard microcircuit comprising: a programmable digital input/output pin, the sacrificial track connected between the input/output pin and a power supply pin of the microcircuit, the microcircuit being programmed to test the state of the input/output pin to determine the implementation of the encryption function.

Alternatively, the tag may comprise an antenna circuit configured to ensure a continuity detection function, the sacrificial track being connected to the antenna circuit such that its rupture shifts the frequency tuning of the antenna circuit, the shift in the tuning frequency being selected such that the power received by the microcircuit is reduced to a level insufficient for implementing the encryption function but sufficient for implementing the basic function.

The tag may include: a flexible substrate strip; an antenna included in the antenna circuit; a capacitor connected to the antenna circuit; a sacrificial impedance; and the sacrificial track running along the strip to connect the sacrificial impedance to the antenna circuit.

The tag may include two metal surfaces facing each other on opposite sides of the substrate in an area of interest of the substrate, configured so that perforation of the area of interest causes a permanent short circuit between the two surfaces; and a circuit configured to detect the short circuit between the two metal surfaces.

Alternatively, the tag may comprise a sacrificial substrate comprising a conductive track connecting the sacrificial impedance to the antenna circuit, the track being arranged to serpentinely occupy a region of interest of the substrate such that perforation of the region of interest severs the conductive track.

The antenna may include turns wound in a ring shape around a central region of the ribbon; the sacrificial impedance may be provided at a first end of the ribbon; and the sacrificial track may include a loop extending to the second end of the ribbon.

The tag may include several ribbons intersecting at the antenna region, the sacrificial track forming a loop in each ribbon segment extending from the antenna except for the ribbon segment supporting the sacrificial impedance.

The tag may include several ribbons intersecting at the antenna region, the sacrificial track forming a loop in a ribbon segment relative to one ribbon segment supporting the sacrificial impedance.

A container is provided comprising: a cap and a tag of the above-mentioned type, wherein the substrate area carrying the antenna has a diameter smaller than that of the cap and is fixed to the container and cap by glue so that the antenna is centered on the cap.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages and features will become more apparent from the following description of certain embodiments of the invention, which are provided for illustrative purposes only and are shown in the accompanying drawings, in which:

■ Figure 1 shows an embodiment of an anti-counterfeiting NFC tag for a bottle;

■ Figure 2 is a block diagram of an equivalent circuit of the device of Figure 1;

■ Figure 3 shows an example of the use of the device of Figure 1 on a wine bottle;

■ Figure 4 is an alternative to the device of Figure 1;

■ Figure 5 shows another embodiment of an anti-counterfeiting NFC tag for a bottle;

■ Figure 6 shows an example of the use of the device of Figure 5 on a wine bottle;

■ Figure 7 shows another embodiment of an anti-counterfeiting NFC tag for a bottle;

■ Figure 8 is a block diagram of an equivalent circuit of the device of Figure 7;

■ Figure 9 shows an alternative to the arrangement of Figure 7;

■ Figure 10 shows another embodiment of an anti-counterfeiting NFC tag for a bottle;

■ Figure 11 shows another embodiment of an anti-counterfeiting NFC tag for a bottle; and

■ Figures 12 and 13 show alternatives to the label of Figure 11 in two forms that are industrially feasible using current technology.

DETAILED DESCRIPTION

In the context of the aforementioned U.S. Patent 7,898,422, once the bottle has been opened, the NFC device becomes silent. However, the user may wish to review the information again, for example, to share it with a friend, or to visit the manufacturer's website to order a new bottle.

Tags of the type described in U.S. Patent Application 2005-0012616 do not distinguish between the sealed or open state of a container in the information returned by the tag. Indeed, the information returned is the same regardless of the antenna being sacrificed, as long as the tag reader can present the tag in its antenna-less mode.

The type of dual tag described in the aforementioned U.S. Patent Application 2007-0210173 requires two separate NFC circuits and two different steps for attaching the tag to the object for protection, which increases manufacturing costs. Moreover, each independent NFC circuit maintains its full functionality when interrogated by a tag reader.

A contactless anti-counterfeiting device, such as an NFC-type device, is provided in the form of an inexpensive label for use with containers, particularly bottles or vials. Furthermore, the label is designed so that it allows authentication when intact, but only allows the reading and transmission of information when it is destroyed after the container is opened. Indeed, when the container is opened, the user only wishes to read the information available on the contactless device without performing any authentication.

Figure 1 shows a first embodiment of a counterfeit-resistant NFC tag, which will be referred to as a "dual-mode" tag. The tag is in the form of a strip 10 of insulating material used as a substrate, with conductive tracks formed using common RFID tag manufacturing techniques. One end of the strip is enlarged to accommodate an NFC antenna 12 formed from several turns of conductive track.

Microcircuit 14 is mounted near the connection between strip 10 and antenna 12 and is connected to the antenna terminals via track 12-1 on one side of the antenna and track 12-2 on the opposite side, which connects the ends of the inner turns of the antenna via vias 16a. Vias 16b couple microcircuit 14 to track 12-2.

The microcircuit 14 is flip-chip assembled or secured with a conductive adhesive. It integrates NFC device management functionality. Because the device can provide authentication, it is an active device, meaning it integrates a microprocessor and encryption functionality. The microcircuit then draws power from the energy supplied to the antenna via an NFC reader, which can be a smartphone, tablet, watch, or other device equipped with an NFC interface.

Tracks 12-1 and 12-2 extend to opposite ends of the strip, where they are respectively connected to two conductive surfaces formed on two sides of the strip. These opposing conductive surfaces form a sacrificial capacitor C1s.

The device is designed to protect containers such as bottles, so that the central portion of the strip is placed across the container's sealing element 18 (e.g., a cork). This is desirable so that when the bottle is opened, that is, when cork 18 is pulled out, the strip breaks and simultaneously severs rails 12-1 and 12-2. To this end, the bond between the strip and the container is designed to have a breaking strength greater than the strip's own. Glue is used to achieve a high bond strength, and the required breaking strength is ensured by applying the glue to the strip over a sufficient surface area.

As shown, the breaking strength of the strip is also reduced by providing break points 20 near the cork. Preferably, these break points are located at the edges of the bonded areas of the strip, which induce fracture-promoting stresses.

The tape is bonded to the container by the face that bears the bulk of the conductive track. The adhesion of the track to the container is generally greater than the adhesion of the track to the tape. As a result, any attempt to remove the label causes the conductive track to break, which causes it to remain stuck to the container.

The rails are typically aluminum, which makes it difficult to repair severed rails by welding or brazing due to the insulating oxide layer that forms on aluminum when exposed to air.

FIG2 is an equivalent circuit diagram of the device of FIG1 . The microcircuit 14 includes a dedicated microcontroller UC that implements the logic and analog functions of the microcircuit, including the power supply to the circuit by the field supplied to the antenna by the NFC reader, the demodulation of the signal transmitted by the reader, the modulation of the impedance of the antenna for transmitting the signal to the reader, and the generation of a security key for authenticating the information transmitted.

The microcircuit further includes a capacitor C1 connected across antenna 12. Tracks 12-1 and 12-2 connect a sacrificial capacitor C1s connected in parallel with capacitor C1. Antenna 12 and capacitors C1 and C1s form an antenna circuit whose tuning frequency is determined by the sum of the values of capacitors C1 and C1s and by the antenna's inductance. These values are selected to tune the antenna circuit to a typical nominal frequency, for example, 14 MHz, chosen for good interoperability between standard-compliant devices.

After the ribbon is severed, when sacrificial capacitor C1s is separated from the antenna circuit, the antenna circuit is tuned to a frequency offset beyond the nominal frequency, for example, 17 MHz, which is determined solely by capacitor C1 and the antenna's inductance. As a result, although power is provided to the device via the reader's field, the transmitted power is low.

In order to carry out authentication operations, the microcontroller UC of the microcircuit 14 has cryptographic functions. The microcontroller comprises a general purpose processor CPU assisted by a cryptographic coprocessor CCP.

Simply reading the information stored in the microcircuit and transmitting it via the antenna does not place significant demands on the CPU and requires very little electrical power. Furthermore, no coprocessor CCP is used. Current consumption can be less than 1 mA. This power level can even be achieved by tuning the output of the antenna circuit.

However, cryptographic operations are both CPU and coprocessor CCP-reliant and consume several milliamps of current. If the antenna circuit is too far out of tune, it cannot provide this power level even when the reader is in contact with the strip.

Using these components, assuming that C1+C1s is the value required to obtain an antenna circuit tuned to the nominal frequency, the value of C1 is selected so that in the absence of capacitor C1s, the antenna circuit is tuned to be sufficient to generate the required power for simply reading information and information transmission, but not enough to generate the power required for encryption operations.

In the example where the nominal frequency is 14 MHz, desired operation is obtained when an offset tuning frequency of approximately 17 MHz is selected in a given technology.

The microcircuit is then programmed to systematically begin with information generation and end with encryption operations. Destroying the ribbon disconnects capacitor C1s from the antenna circuit, causing the antenna circuit's tuning to shift. In this case, when the microcircuit begins encryption operations, the supply voltage collapses, causing the microcircuit to reset. The microcircuit restarts, and the same cycle begins again.

Figure 3 shows an exemplary use of an anti-counterfeiting NFC tag of the type shown in Figure 1 on a wine bottle 30. (For clarity, the spaces between elements have been exaggerated.) Cork 18 is flush with the top of the neck of the bottle. The center portion of band 10 horizontally covers cork 18. The ends of the band are folded vertically downward to fit over the sides of the neck and secured to the neck with adhesive 34. The band is flexible enough to fold over the top of the neck and conform to its radius. In this case, the antenna is preferably flat.

Wine bottles are typically provided with a protective cap 32 that covers the cork and the upper end of the neck. As shown, the cap can also cover the strip 10. In this case, since the cap is typically metal, it is preferred that the antenna 12 be external to the cap so that it is exposed to electromagnetic fields. The length of the strip 10 is selected accordingly.

Thus, the designed NFC tags can be read by consumers using their NFC smartphones or other NFC readers. Specifically, when the tag is intact, they can use the security key available in the tag to authenticate the product to confirm that the product conforms to the information provided by the tag via an authentication server and a dedicated application. Even when the anti-counterfeiting tag is damaged, the same application or a universal application can be used to query the product's characteristics, including the type of information that appears on the bottle's paper label. Several bottles from the same batch may have tags that share the same identifier or key.

The rails 12-1, 12-2 of FIG1 can be relatively long and form parasitic antennas that capture spurious electromagnetic fields. When the ribbon 10 is wrapped in a metal cap ( FIG3 ), the cap provides protection from these magnetic fields. In other scenarios, the cap is transparent to the fields or is absent.

Figure 4 shows an alternative to the tag of Figure 1 that is less sensitive to parasitic fields. The pair of tracks 12-1, 12-2 is configured to form a twisted pair. For this purpose, for example, the tracks 12-1 and 12-2 are not actually "twisted," but meander in relative phase.

A particular wine connoisseur may wish to retain the cork, which has essential information about the wine. In this case, it would be convenient for the active portion of the NFC tag to remain on the cork so that the connoisseur can obtain more detailed information about the wine by reading the information contained in the tag using, for example, a smartphone.

Figure 5 shows an embodiment of an anti-counterfeiting tag dedicated to this use. The NFC tag is designed so that its active part (i.e. antenna 12 and microcircuit 14) remains fixed on the upper end of the cork and allows the information to be read without authentication once the cork is extracted.

The tag herein comprises a substrate in the form of two intersecting strips 10a and 10b. Antenna 12 is positioned at the intersection of the two strips and comprises turns wound in a circular pattern around a central area large enough to allow a bottle opener to penetrate without damaging the antenna. As shown, the central area of the substrate includes an opening 50 to facilitate penetration and limit deformation of the substrate. The outer diameter of the annular area of antenna 12 and the supporting substrate is at most equal to the diameter of a cork.

The tape segments, or wings, extending radially from the antenna are designed to be separated from the central area when the cork is removed and, for this purpose, may include breakpoints 20 near the outer diameter of the annular area carrying the antenna. Microcircuit 14 and its connecting tracks to the antenna circuit are arranged within the annular area of the substrate so that they do not remain on the tape segments when the cork is removed. Sacrificial capacitor C1s is provided at the distal end of one of the wings, here the right wing, which is part of tape 10a.

This structure is similar to that of Figure 1 , except for the right wing and antenna, which have sacrificial capacitor C1s. The additional wing makes accessing the cork without damaging the label more difficult. As shown, before connecting to the corresponding pins of microcircuit 14, track 12-1 loops through each of the three additional wings, so that if any wing is damaged, the track is severed.

FIG6 shows an exemplary use of an anti-counterfeiting NFC tag of the type shown in FIG5 on a wine bottle 30. (For clarity, the spaces between elements have been exaggerated.) Cork 18 is flush with or slightly recessed from the top of the bottle neck. The central annular portion of the substrate carrying antenna 12 is aligned over the upper end of cork 18 and secured thereto by adhesive layer 36. The wings of strips 10a, 10b are folded vertically downward to fit over the sides of the neck and secured to the neck by adhesive layer 34.

To open the bottle, a bottle opener can be inserted through the label's central opening 50 without damaging antenna 12. Removing the cork 18 destroys the wings and, consequently, removes sacrificial capacitor C1s from the antenna circuit. The active portion of the label, without sacrificial capacitor C1s, remains attached to the upper end of the cork. This active portion remains operational for simple reading of information, but is not used for authentication. Authentication is only possible if the label is intact—that is, attached to an unopened bottle.

A protective cap 32 typically surrounds the upper end of the neck and includes the wings of the strips 10a, 10b. If the cap is metallic, it preferably includes a portion 32-1, shown in gray, facing the antenna and transparent to magnetic fields. To facilitate the passage of field lines at the periphery of the antenna, portion 32-1 preferably has a diameter greater than that of the antenna. It should be noted that this embodiment provides a discreet NFC tag that does not alter the appearance of the bottle, something that some producers or manufacturers may desire.

The tag of FIG5 is shown in the form of two intersecting strips 10a and 10b forming four radial wings. The number of wings is arbitrary, but is preferably at least two. Not all wings need have conductive tracks—for example, a tag can be provided with a first pair of opposing wings bearing tracks and a second pair of opposing wings without tracks. The number of wings may also be an odd number.

The anti-counterfeiting NFC tags in Figures 1 and 5 are effective for identifying bottles that have been opened and potentially refilled with products from questionable sources. However, they do not use a syringe to detect the removal or replacement of the contents, such as with the Coravin ^™ process, in which the cork is pierced with a syringe and the contents are extracted when an inert gas is injected into the bottle. Such technology would leave the tag intact.

Figure 7 shows an embodiment of an NFC tag that can detect cork perforation attempts. Here, the tag is made on a substrate with the same cross-sectional shape as the tag in Figure 5. However, the central part that accommodates the antenna 12 has a diameter larger than the diameter of the cork. The antenna 12 is wound in a ring shape in the space between the edge of the neck and the cork, leaving a central area the size of the cork, wherein the central area forms an area of interest to be protected. This central area is used to form a sacrificial capacitor C2s. The capacitor C2s is formed by two metal surfaces facing each other, one (gray) formed on the upper surface of the substrate and the other (black) formed on the opposite surface of the substrate. In order to distinguish them in the figure, the metal surfaces are not shown with the same size - in fact, they are the same size and fill the area of interest corresponding to the top of the cork. The microcircuit 14 is also preferably arranged in this area.

In this embodiment, antenna 12 and sacrificial capacitor C2s are connected in series. The lower surface of the capacitor (black) is directly connected to the first pin of microcircuit 14. A conductive track 70 connected to the upper surface of the capacitor (gray) includes a loop extending into each of the ribbon segments or wings extending from the central region. The final loop passes through the substrate via a via 72 and connects to the outer end of antenna 12. The inner end of the antenna is connected to the second pin of microcircuit 14.

A label of the type shown in FIG6 is mounted on the bottle in the manner shown in FIG6 . The central area of the label is glued over the entire surface on the cork. Any attempt to access the cork then results in a perforation of the two metal surfaces of the sacrificial capacitor C2s. During perforation, the plastic substrate between the two metal surfaces is permanently compressed while, following the movement of the perforating object (needle or corkscrew), the metal of the upper surface extends and reaches the lower surface. The lower surface deforms less than the upper surface because it rests against a glue layer that is generally harder than the substrate. This results in a bending of the deformed areas of the upper and lower metal surfaces, causing a permanent short circuit between the two surfaces of the capacitor, even when the perforating object is pulled out. This short circuit also occurs when the metal surface of the capacitor is aluminum, because aluminum is forged in an inert atmosphere to prevent oxide formation and, since they are protected by the substrate, the areas in contact with the two surfaces are free of oxide.

The short-circuiting of this sacrificial capacitor C2s is used to de-tune the antenna circuit so that the NFC device operates in a degraded mode, ie so that it provides a reading function instead of an encryption function.

Furthermore, the removal of the cork severs the wings and the conductive track 70. This severance disconnects the microcircuit from the antenna 12, so that the NFC device becomes inactive. The tag is then silent.

FIG8 is an equivalent circuit diagram of the device of FIG7 . As previously indicated, sacrificial capacitor C2s and antenna 12 are connected in series between two pins of microcircuit 14. The antenna circuit thus comprises capacitance C1 of the microcircuit connected in series with capacitance C2s and the inductance of antenna 12. When capacitance C2s is short-circuited, antenna 12 is connected directly across capacitance C1.

Given these two configurations, the component values are chosen to achieve tuning to the desired nominal frequency when capacitor C2s is integrated, and a tuning offset that places the device in degraded mode when capacitor C2s is shorted. The value of the sacrificial capacitor C2s is determined by the cork diameter and the thickness of the substrate.

Using a 38-micron PET substrate typically used for RFID applications and a wine bottle cork diameter (21 mm), a capacitance of approximately 116 pF is obtained. Providing nine turns for the antenna and a value of 104 pF for capacitor C1 results in a tuning frequency of approximately 15 MHz, which is close enough to the desired nominal frequency of 14 MHz to ensure all functions (reading and encryption). When capacitor C2s is short-circuited, a tuning frequency close to 11 MHz is obtained, which is just enough to ensure the reading function.

Figure 9 shows an embodiment of an NFC tag capable of detecting cork perforation attempts. It follows the same format as the tag in Figure 1, using antenna 12 offset to one end of the strip. The central portion of the strip covering the cork 18 bears the metal surface that forms the sacrificial capacitor C2s. Microcircuit 14 is mounted in series in a track 12-1 extending through the strip. After looping toward the far end of the strip, this track is further connected to the upper metal surface of capacitor C2s. The capacitor's lower metal surface is connected to track 12-2.

7, this embodiment provides greater freedom in implementing the antenna 12 and allows the cork to be covered integrally with the metal surface. However, it may not be suitable in situations where it is desired to conceal the tag entirely beneath the cap.

FIG10 shows an alternative tag similar to FIG1 that can also detect perforation attempts. In contrast to the tag of FIG1 , one of the connecting tracks of the sacrificial capacitor C1s, here track 12-1, has a compact, serpentine-shaped structure that occupies the entire surface area of the area of interest to be protected. The pitch of the serpentine is preferably smaller than the diameter of a needle that can be used for perforation, so that insertion of the needle severs the track at at least one location. If track 12-1 cannot be configured with a sufficiently small pitch, a second track 12-2 on the other side of the substrate is configured as a complementary serpentine, so that segments of track 12-2 intersect segments of track 12-1, effectively dividing the pitch by two.

When the cork is removed (destroying the strip and tracks 12-1 and 12-2), and when the cork is perforated (destroying the track segment in the protected area), the tag will operate in a degraded mode, allowing only reading of the information.

If it is desired that the discrete tag can be retained on the extracted cork so that the information can be read, the structure of Figure 10 can be transferred to the cross structure of Figures 5 or 7.

Many variations and modifications of the embodiments described herein will be readily apparent to the skilled person. In order to achieve a controlled tuning shift of the antenna circuit in response to a rupture of the tag, sacrificial capacitors (C1s, C2s) are disclosed as a preferred embodiment - it is of course possible to use equivalent techniques to cause a tuning shift of the antenna circuit, for example, by using a sacrificial inductor or other sacrificial impedance in place of the sacrificial capacitor.

Controlling the component values of the antenna circuit to achieve the desired tuning offset, i.e., to provide sufficient power for the reading function but insufficient power for the encryption function when the tag is compromised, can be difficult under certain conditions. A feature of the dual-mode devices disclosed to date is that they can use an off-the-shelf microcircuit 14 having only two undifferentiated pins, which simplifies industrialization and reduces costs in certain circumstances.

Inside Secure sells an NFC device management microcircuit called VaultIC ^™ 152, which has five pins: two pins connected to the antenna, a ground pin (GND), a programmable digital input/output pin (IO), and a pin (VCC) that can be used to power the microcircuit from a battery or to power other components from energy harvested from the antenna. Such a microcircuit can be used in a less constrained dual-mode tag structure that implements two operating modes in large-scale manufacturing.

FIG11 schematically illustrates an NFC tag structure that provides full functionality when intact and, when compromised, limited functionality without encryption. Thus, the microcircuit 14 includes five pins, two of which are connected to the antenna 12 in a structure similar to that of FIG1 . The conductive tracks 12-1 and 12-2 of the previous figure are here labeled 12'-1 and 12'-2, which are separated from the antenna track 12 and are respectively connected to one of the power pins, for example, the ground pin GND and the input/output pin IO of the microcircuit 14. Tracks 12'-1 and 12'-2 may be located on the same side of the strip 10 and connected to each other at the distal end of the strip to form a loop that crosses a sacrificial area (for example, corresponding to the position of the cork 18).

In some VaultIC microcircuits, the input/output pin IO is pulled toward the power supply line VCC via a resistor, resulting in a logic-high level when it is unconnected. In the configuration of Figure 11 , the IO pin is held at a logic-low level by loops 12'-1 and 12'-2. When the loop is broken, the IO pin goes high.

Thus, the programmable microcircuit 14 can be programmed to test the voltage level of the IO pin each time it is read. When the voltage level is low, i.e., when the tag is intact, the program in the microcircuit can be designed to perform all the desired operations, i.e., the generation of plaintext information and the execution of authentication operations using cryptography. When the voltage level is high, i.e., when loops 12'-1 and 12'-2 are open, the program in the microcircuit can be designed to generate plaintext information but omit the authentication operations.

One of the tracks 12'-1, 12'-2 may be of serpentine shape as shown in Figure 10, while the other is located on the opposite face of the strip. This allows the severing of the track to be detected by removal of the label or perforation of the cork, resulting in skipping the authentication step.

In other applications, the input/output pin 10 of the microcircuit 14 can be used to detect short circuits rather than open circuits. Thus, in a configuration similar to that shown in Figures 7 and 9, the 10 pin can be connected to one of the metal surfaces of the sacrificial capacitor C2s, and the other metal surface connected to ground. A permanent short circuit between the metal surfaces forming the sacrificial capacitor C2s then makes a cork puncture detectable. When the cork is not punctured, the 10 pin is high. When the capacitor is punctured, it shorts and pulls the 10 pin to ground. In this case, compared to previous applications, the microcircuit inverts the logic to react to the state of the 10 pin.

FIG12 shows an alternative to the label of FIG11 ; the antenna 12 is positioned in the center of the strip so that, when the label is placed on the neck of a bottle, it is centered over the cork. A microcircuit 14 is located inside the antenna windings. The two wings on either side of the antenna intersect via loops 12'-1 and 12'-2, so that severing one of the wings is sufficient to interrupt the loop. Each wing may have several transverse cuts 20' on each edge near the center, serving as rupture points.

Such a label can be attached to a bottle solely by its wings. When the bottle is opened, the wings are destroyed when the user cuts off and removes the cap covering the cork and label. The central portion of the label remains usable, without the authentication function needed to share the information it contains.

FIG12 corresponds to an actual working prototype produced using the aluminum track technology. The diameter of the central portion of the tag is 25 mm, which is the diameter of the neck of a wine bottle. In its current state, this technology produces a relatively large through-hole that would occupy a large surface area in the central region of the antenna, which could be an obstacle to manufacturing tags according to FIG5 and 7, as those tags require a clean area at the center of the antenna.

Figure 13 shows a prototype tag of the type of Figure 12 made using copper track technology. This technology can produce tracks and vias with smaller features than aluminum technology, thereby freeing up a wide center area, making it easy to manufacture tags of the type of Figures 5 and 7.

Tags with offset antennas (in particular those of Figures 1 and 11) can also be used on containers with metal closure elements by providing the rear side of the tag at the level of the antenna with an electromagnetic insulating layer such as ferrite.

From FIG. 11 , a continuous detection technique using an IO pin of the microcircuit 14 has been disclosed, which detection technique essentially consists in observing permanent variations in the voltage level of the IO pin.

To count several tag repair options, the microcircuit is designed to emit a pseudorandom logic sequence on an IO pin. A sacrificial circuit is then connected between pin IO and a second input/output pin programmed to compare the input logic sequence with the sequence transmitted on pin IO. If the microcircuit detects that the input sequence differs from the transmitted sequence, it can switch to a mode with limited functionality.

In practice, this type of detection can be implemented without additional circuitry. Microcircuits used in this type of product are often equipped with an "active shield" that protects the microcircuit from intrusion, as described, for example, in U.S. Patent 8,296,845. The active shield typically consists of a dense network of conductive tracks implemented on the last metal face of the chip. The tracks receive a logical pseudo-random sequence at one end, and a circuit collects the signals at the other end to compare them with the expected signal. If a signal mismatch is detected, the microcircuit is programmed to take preventive measures.

In this case, the microcircuit is easily modified to extend one of the active barrier tracks through an input/output pin and a sacrificial loop. The interruption of the sacrificial loop then has the same effect as cutting the active barrier track.

Claims (11)

1. A near-field magnetically coupled non-contact tag, comprising: • A control microcircuit, which includes programmable digital input/output pins and is configured to implement plaintext information generation and authentication operations using encryption; • A sacrificial conductive track disposed across the sacrificial region of the tag, the sacrificial conductive track being connected between the input/output pin and the power supply pin of the microcircuit; and The microcircuit is configured to generate the plaintext message and omit the authentication operation when the state of the input/output pin indicates that the sacrificial conductive track has been destroyed. 2. A near-field magnetically coupled non-contact tag, comprising: A control microcircuit configured to perform authentication operations for generating plaintext information and using encryption; Sacrificial conductive tracks are disposed across the sacrificial region of the label; and An antenna circuit in which the sacrificial conductive track is connected, such that its breakage causes a frequency tuning shift in the antenna circuit, the shift in the tuning frequency being selected such that the power received through the microcircuit is reduced to a level insufficient to perform the authentication operation but sufficient to perform the generation of the plaintext information. 3. The label according to claim 2, comprising: • Foldable substrates in the form of strips; • Antenna included in the antenna circuit; • Capacitors connected to the antenna circuit; • Sacrificial resistance; and • The sacrificial conductive track disposed on the strip to connect the sacrificial impedance to the antenna circuit. 4. The label according to claim 3, wherein: The antenna comprises turns that are wound in a loop around the central region of the strip; The sacrificial impedance is located at the first end of the strip; and The sacrificial conductive track includes a loop extending toward the second end of the strip. 5. The tag of claim 4, comprising a plurality of strips intersecting at the antenna, wherein the sacrificial conductive track forms a loop in each strip segment extending from the antenna, except for the segment supporting the sacrificial impedance. 6. The tag of claim 4, comprising a plurality of strips intersecting at the antenna, wherein the sacrificial conductive track forms a loop in a strip segment relative to a segment supporting the sacrificial impedance. 7. The tag of claim 3, wherein the strip includes a break point between the antenna and the sacrificial impedance. 8. The tag of claim 3, wherein the sacrificial conductive track comprises two segments located on either side of the strip and is configured as a twisted pair. 9. A container comprising: Cork; and • The label according to claim 4, wherein the substrate region carrying the antenna has a diameter smaller than the diameter of the cork, and is fixed to the container and the cork by adhesive such that the antenna is centered on the cork. 10. The container of claim 9, wherein the conductive track of the label is located on the side of the strip facing the container, such that an attempt to remove the strip would damage the conductive track. 11. The container of claim 9, in the form of a bottle, the bottle comprising enclosing the cork, the neck of the bottle, and the cap of the strap, the cap comprising a magnetically permeable material in the vicinity of the cork.