Technical Field

The present invention relates to a methodology for the identification and traceability of materials during manufacturing processes of products.

In particular, the present invention relates to a methodology for the identification and traceability of leather and leather-like materials throughout the manufacturing process of leather and leather-like products.

Background Art

The term traceability refers the ability to verify the history, location, or application of an item by means of documented recorded identification [Glossary," ASME Boiler and Pressure Vessel Code, Section III, Article NCA-9000]. In particular, in the manufacturing industry, product traceability indicates following the product, throughout the entire production process. Traceability requires that, at each stage of the production process, new information (traces) be created regarding that specific stage. Such traces are collected, stored and associated to each single finished product.

The concept of product identification, which is strictly related to traceability, refers to the possibility of discriminating each single item within a homogeneous lot of similar items, by retrieving all the identification information (regarding the production, transformation, quality status, etc.) of that item.

Traceability and identification are extremely important for manufacturing companies, not only for ensuring safety to the customers (by guaranteeing on the origin of a product or of the raw materials) and comply with regulations, but also for optimizing management and logistics.

Traceability and identification allow to go back to ascertain the characteristics of the product (e.g. constitutive parts and components, production lot, production stages); to reconstruct the information on its the technical/commercial history (e.g. change of property, change of destination); for product recall after the discovery of safety threats (e.g. for the health or for the environment) or product defects; etc.

Indeed, product traceability is important for the manufacturing company not only for pursuing customer advocacy policies, but also for logistics and operations management. In fact, for logistics-related purposes, the availability of product-related information is crucial for the optimal management of the numerous production flows that are intrinsically intertwined with the distribution and storage operations.

To allow the identification and the tracing of a product, it is necessary to mark the product, thus making it a uniquely identifiable entity throughout its lifecycle.

There are numerous marking systems and modalities, depending on the specific requirements imposed by the specific application fields and on the nature of the product to be marked. However, in the textile and leather industry, traceability still represents a tough challenge. In fact, in these fields, the production processes are fragmented and include operations that are often delocalized or outsourced. As a result, conventional traceability methods fall short of providing effective solutions.

With regards to the textile industry, marking solutions generally belong to either of the following broad categories:

marking with tags and/or labels;

marking through chemical-physical processes. Tag-based marking solutions are the most widespread: all the necessary identification information are associated to a customized code, which is applied to and carried by each single item that must be traced. Tag-based marking is clearly intended for identifying and tracing specific items which, from the moment of application of the tag, are virtually indivisible (such as clothes). Barcoding is one of the most widespread tag-based marking solutions. A barcode is an optical machine-readable representation of data relating to the object to which it is attached. The barcodes are usually printed directly on the packaging of the item or on a separate label that is attached to the item. Barcodes are read by optical scanners, which allow to associate the code to the corresponding information.

Another widespread tag-based marking technology is radiofrequency identification technology (RFID). An RFID system consists of a reader and of one or more transponders (attached to the item to identify and trace), which transmit a radiofrequency signal in response to an order received by a remote reader station. The response of the transponder consists of an identification code related to the item on which the transponder is applied: the identification code serves as a key to find the item-related information inside a dedicated archive or database. Indeed, RFID transponders are typically equipped with a microchip that, in addition to managing the interaction between transponder and reader station, can also store a limited amount of data.

With regards to tag-based marking, WO 2005/008294A1 discloses a method of identifying an object and a tag carrying identification information: the invention described therein employs magnetic particles or electrically conductive particles as markers. However, said particles are to be deposited on a host medium which, in turn, should be applied to the item to be traced. As a result, if the marked item undergoes severe mechanical, thermal or chemical processes (such as those that are typical of the leather manufacturing process), the persistence of the markers may not be guaranteed.

Similarly, DE102009020208A1 discloses an invention related to a method for coding of products by means of a magnetic composition containing magnetic nanoparticles, and a product having such an encoding. However, also according to this invention, the persistence of the markers may not be guaranteed.

Tag-based marking, however, cannot fully satisfy the requirements of the textile and leather manufacturing industry (in particular, those related to counterfeiting); in fact, the applied tags may be destroyed, damaged or removed when the product undergoes the harsh processes required for leather manufacturing.

As for chemical-physical marking, this represents relatively new technology; and it is still undergoing an intensive research and development stage. Chemical-physical marking is considered as the most suitable technological solution for marking "continuous products", where this expression is used to indicate those products (such as yarn, textiles, and natural fibers), which are used as raw materials and which are bound to undergo particular working processes, still remaining identifiable and traceable.

At the state of the technique, in the textile industry, chemical or optoelectronic marking of fibers is used, including the tracing fiber technique (which, however, is applicable only in the carding process); the employment of heavy metals (with the related negative consequences on the environment); the use of fluorescent or phosphorescent materials (which, however, must not come into contact with bleaching products); and the adoption of nanotechnologies. However, the aforementioned solutions cannot be applied to the specific needs of the leather manufacturing process.

In general, the first requirement that must be possessed by a methodology for marking leather and leather-like materials is that it must not have a significant effect on the features and characteristics of the finished material: for leather and leather-like materials, it is crucial that the presence of identification markers does not alter the color, touch, thickness and handle characteristics. Also, the presence of identification markers must not affect cutting, gluing, sewing and shaping the material. Overall, the candidate marking technology should not impact substantially the leather manufacturing process.

Additionally, the identification markers must not be visible to the naked eye; identification should be made possible within the factory with simple means. The identification markers should also be resistant to physical, chemical and thermal conditions during the manufacturing operations that are necessary to obtain the finished leather or leather-like products.

As a matter of fact, at the state of the technique, for the manufacturing of leather (to be used, for example, for sofa covers), there is no effective solution for the traceability of the raw materials. This is mostly due to the peculiarity of the raw materials, the hides, which are organic and protein- based and hence subjected to quick degradation.

Additionally, the leather manufacturing process (which consists of three major sub-processes, namely preparatory stages, tanning and crusting) requires the hides to undergo severe mechanical and chemical processes that allow to eliminate components (e.g. subcutaneous tissues, skin and fat, whose presence typically indicate low quality of the product) and to obtain a non-putrescible product, namely leather. Often, some of the sub-processes, especially tanning, are outsourced or delocalized. The tanning process changes completely the appearance of the obtained leather with respect to the appearance of the raw hide; hence, when the hides are sent to tanning and return to the company, it is crucial to verify that the product that has been sent back in is the same material that had been originally sent out. Based on these considerations, it is clear that, in the leather manufacturing industry, the improvement of authentication systems is vital to guarantee traceability along the chain from the sourcing of raw materials at the abattoir to their use when manufacturing a finished product.

It goes without saying that adopting tag-based traceability systems is practically unfeasible, because, as already mentioned, the tanning process is so severe that tags would be removed or destroyed.

Therefore, it is necessary to define a traceability and identification system of the product along the different steps of the process, so as to identify raw hides and guarantee the identification of the hides throughout the leather manufacturing process. In this way, the manufacturer would be reassured about possible fraudulent substitutions of the raw materials and would avoid being involuntarily led to sell low-quality products. Disclosure of Invention

The present invention pertains to a methodology for the identification and traceability of materials in industrial process, with particular focus on the traceability of leather and leather-like materials throughout the manufacturing process of leather or leather-like products. By allowing to keep track of the marked leather or leather-like materials throughout the entire leather manufacturing process, the present invention allows verifying possible fraudulent modifications/substitutions/operations or even honest mistakes in the employment of the materials.

The methodology object of the present invention comprises, at least, the employment of the following: identification markers; a method for permanently embedding the markers inside the item to be traced; a device for generating an electromagnetic signal to be used as stimulus for the marked material; a device for acquiring the response of the marked material to the applied stimulus; and a device for recording the aforementioned response, said methodology being characterized by the following steps:

i. embedding the markers in the leather or leather-like material to be traced, by means of said marker-embedding device;

ii. stimulating the leather or leather-like material to be traced with a specific electromagnetic radiation;

iii. acquiring the response of the marked leather or leather-like material to the electromagnetic stimulus by means of the external device;

iv. recording the response of the marked leather or leather-like material to the electromagnetic stimulus by means of an acquisition unit.

Said methodology is also characterized in that the marker-embedded portion of the leather or leather-like material responds to an electromagnetic stimulus differently from how a marker-free portion of the same material responds to the same electromagnetic stimulus and also differently from how the same portion of material would respond to the same electromagnetic stimulus if the portion was marker-free. The identification markers are also characterized in that they are permanently embedded inside the item to traced, following a pre- established pattern or a random distribution.

Said identification markers are also characterized in that they are inert and chemically and thermally stable with respect to the leather and to leatherlike materials in which they are embedded; and, therefore, the presence of the markers does not provoke modifications or any other undesired effects (e.g. stiffness, frays, unraveling) that could compromise the subsequent working operations and the final quality of the leather product.

The method for permanently embedding the markers is characterized in that it is non-destructive and only minimally invasive in respect to the material in which the markers are to be embedded; in this way, the integrity of the leather or leather-like material is preserved and the final quality of the product is not compromised.

The method for embedding the markers is characterized in that the markers are permanently embedded under the surface, at a depth that may vary in the range of 0.2 mm to 1.0 mm, depending on the thickness of the material to be marked.

This method for embedding the identification markers makes the markers resistant to thermal, mechanical, chemical, physical processes that are part of leather manufacturing process (such as fleshing, dehairing and trimming).

Because the markers are embedded inside (rather than attached on the surface of) the leather or leather-like material, they remain permanently inside the material, in spite of possible reduction of the thickness of the marked material, due to the production process. The markers are also characterized in that, after the leather manufacturing process is complete, they are invisible to the human eye, as no visible trace is left on the surface of the leather.

Brief Description of Drawings Fig. 1 shows a schematization of a marker-embedding device (1) used for embedding the identification markers (3) in the leather or leather-like material (2) to be traced.

Fig. 2 shows a possible way of embedding the identification markers (3) inside the leather or leather-like material (2), wherein an array (4) of marker-embedding devices is used for obtaining a pre-established pattern (5) of identification markers (3).

Fig. 3 shows a simplified schematization of the top-view of a leather or leather-like material (2), with the identification markers (3) are embedded, and a cross-section of the same leather or leather-like material wherein the presence of the identification markers (3) in the sub-surface is shown.

Fig. 4 shows a schematization of a first preferred embodiment of the invention, in which an X-Ray scanning device (6) is employed for scanning the leather or leather-like material (2) in which the identification markers (3) are embedded, thus obtaining an identification X-ray image (7).

Fig. 5 shows a schematization of another non-limiting preferred embodiment of the invention, in which a microwave reflectometer (9) connected to an acquisition/recording unit (10) is used to generate a microwave electromagnetic stimulus that is conveyed through an accessory (8) to the portion of the leather or leather-like material (2) containing the sub-surface identification markers (3). Fig. 6 shows an example of the response obtained from the realization of the methodology depicted in Fig. 5, wherein the response to the microwave electromagnetic stimulus is the reflection scattering parameter, which is different in presence (11) or in absence (12) of the identification markers.

Modes for Carrying Out the Invention

As depicted in Fig. 1, the theoretical principle at the base of the present invention consists in employing a device (1) for embedding the markers in the material to be traced (2), in a limited portion of it (3), a number of tracing markers, such as metallic particles, ceramic powder, or a compounds of different nature. It is possible to embed said markers following a pre-established pattern, or a code, or other type of informative comment, which can be associated to the marked material.

When the object to be traced undergoes processes or is moved, it can be subjected automatically, in one or more steps of the manufacturing process, to a traceability-check, for example through X-ray, thus verifying the presence of the identification markers and, hence, the origin of the product and its authenticity (for example, through the identification of specific shapes or pattern given to the embedded markers).

In one preferred non-limiting embodiment of the invention, the marker- embedding device (1) operates similarly to a tattoo gun. In order to facilitate the penetration of the markers (3), these are dispersed into a vector fluid (such as water or acetone), which is inert with respect to the leather or leather-like materials and which evaporates after the markers (3) have been embedded. The method of embedding the markers makes them resistant to the working processes that the raw materials (e.g. hides) undergo throughout the product manufacturing process (e.g. leather manufacturing process).

In one non-limiting preferred embodiment of the invention, as shown in fig. 4, the traceability and identification methodology is based on the difference of the response when an electromagnetic stimulus, in the X-ray frequency band, is applied to portions of the leather or leather-like material in which the identification markers (3) are embedded and to portions of leather or leather-like material (2) without the markers. In this embodiment of the invention, the step for stimulating the leather or leather-like material to be traced is performed employing an X-Ray scanning device (6), which conveys X-Rays on the marker-embedded portion (3) of the material (2). The presence of the markers (3) is verified by acquiring the X-ray image (7) of the marked portion of the leather or leather-like material (2).

As shown in Fig. 2, in another non-limiting preferred embodiment of the invention, the markers (3) can be embedded in the item to be traced through a system of multiple injectors, arranged as an array (4). This configuration of the marker-embedding device allows, if necessary, to activate the "injection needles" and extend the portion of the material carrying the markers or, alternatively, to selectively activate the needles that form a pre-established identification pattern (5) which may be associated to specific information related to the item.

In the final leather or leather-like product, the identification markers (3) are always not visible to the human eye.

In one non-limiting preferred embodiment of the present invention, said device (1) for embedding the markers (3) can be a tattoo gun.

In another non-limiting preferred embodiment of the present invention, shown in Fig. 5, the method for generating the microwave electromagnetic stimulus can resort to a microwave reflectometer (9), which generates the stimulus signal and, through accessories (8), conveys it to the portion of material containing the embedded markers (3). The accessories (8) convey the reflected signal to the microwave reflectometer (9); which, in turn, digitizes the reflected signal and sends it to the acquisition/recording unit (10) for evaluating the corresponding reflection scattering parameter. In this embodiment, the response to the electromagnetic stimulus is the reflection scattering parameter, which behaves differently in presence (11) or in absence (12) of the markers, as shown in Fig. 6. In this preferred embodiment, the identification markers (3) are substances (such as ceramic powders) with a relative dielectric permittivity that is much different from the typical relative dielectric permittivity of leather and leather-like materials.

In another non-limiting preferred embodiment of the present invention, the method for embedding the identification markers resorts to a set of needles that inject the markers in the wetted leather or leather-like material.