Not applicable.
1. Field of the Invention
The present invention relates to multi-level materials, and in particular, to anticounterfeit, security and detection taggants employing such materials.
2. Brief Description of the Related Art
Counterfeiting has been a problem for many years in today's society and lately it has been increasing at an alarming rate. Different types of products ranging from pharmaceuticals, auto and airplane parts and all the way to apparel goods are counterfeited on daily basis. Knock-off versions of real products that are being sold on the markets are at a much lower quality impacting the health and security of the public. Many anticounterfeit devices have been designed and are available in the market, but none of them are completely successful in stopping counterfeiting. The reason is because these types of security taggants can be easily replicated by the counterfeiters, thus defeating the purpose of integrating an anticounterfeit tag into the authentic product. For example, taggants involving hologram and phosphorus technology are not complex enough and as a result are often replicated by the counterfeiters. Hologram taggants can be easily reproduced as devices such as printers and scanners become more sophisticated. More advanced security devices involve quantum dots embedded into a polymer layer as described in U.S. Pat. No. 6,692,031 to McGrew. This device only provides one level of authentication (optical verification), hence making the taggant still vulnerable for the counterfeiters to replicate. These types of anticounterfeit taggants have to be constantly changed to stay one step ahead of counterfeiters. Consequently, there is a vital need for a robust multi-layered anticounterfeit/security taggant. This invention describes an anticounterfeit taggant that is not economically feasible for the counterfeiters to replicate and at the same time it provides multi-level security.
It is also desirable for security purposes to detect environmental materials and conditions; for example, the presence of explosive materials.
The present invention utilizes a wide variety of nanomaterials, micro materials and bulk materials that are all integrated into a taggant to provide the taggant with spectroscopic, magnetic, optical and/or electrical properties. All these properties may be integrated individually or in combination into the taggant. The properties may be manipulated to provide unique signatures that are detectable by various modes of detection. For example, the detection may be carried out by means of optical processes, Raman Spectroscopy, FTIR, magnetic measurements and/or electrical measurements. In one embodiment, the taggant becomes optically active under electrical, optical or magnet excitation. The taggant may be utilized to protect against the counterfeiting of different types of products. The multi-component taggant has a plurality of different types of nano/micro particles and bulk materials including but not limited to: carbon nanotubes, magnetic nanomaterials coated by various other materials (graphitic carbon, polymers, DNA, proteins, etc.), quantum dots, calcium carbonate, hydroxyapetite (nanocrystals), silver nanoparticles, DNA and biological systems. For example, carbon nanotubes (CNTs) and quantum dots with various dimensions may be added to enhance the complexity of the taggant (also called herein a “nano-tag”) by creating complex signatures that are difficult to reproduce. This complex authentication nano-tag is designed in such a way that it will not be economically feasible for counterfeiters to reproduce.
The size of the taggant may be varied and customized for a particular product that the multi-layered complex nano-tag is applied to. In one embodiment, combinations of different types of nano/micro/bulk particles can be embedded onto or into a thin polymer layer. The polymer layer may have an adhesive backing to allow for fast and easy application to a wide variety of products. In another embodiment, the combinations of different types of nano/micro/bulk particles may be incorporated into an “ink” that is deposition or sprayed onto a product. The taggant can be designed to be more complex by adding to the number of different types of nano/micro/bulk structures. By controlling the shape and size of these structures, one can control their optical, magnetic, electrical and spectroscopic properties, thus generating unique identification codes.
The taggant may have the capability to detect gaseous, acoustic, liquid or solid materials or conditions in the environment of the taggant. These detection functions may be combined with anticounterfeit functions in the taggant or the anticounterfeit functions may not be present in the taggant.
These and other features, objects and advantages of the present invention will become better understood from a consideration of the following detailed description of the preferred embodiments and appended claims in conjunction with the drawings as described following:
Embodiments of the present invention are described as follows with reference to
Various types of nano/micro/bulk particles may be incorporated in various ways into a matrix (for example, a natural material or a synthetic polymer) that is preferably chemically and thermally stable to form the taggant. The taggant can be designed in such a way that the various structures in the matrix may or may not be detectable by the human eye. A plurality of different classes of materials (an example using four types of nano/micro/bulk particles 11, 12, 13, 14 is shown in
For the particular embodiment of the taggant 40 shown on
In one embodiment, a nano/micro particle solution can be mixed with a polymer when the later is in a liquid state, then strongly sonicated for a good dispersion of the particles into the polymer. The final solution is poured onto a Teflon surface (it is not limited to this surface, others can be used) to form a thin composite polymer layer 20. For example, poly(methyl methacrylate) (PMMA) is only one example among many other polymers that could be used when designing this type of taggant.
If the polymer is in a liquid state, a set amount is poured onto a Teflon foil. The nano/micro particle solution can be deposited on top of the polymer layer while is it still in liquid form or after it has dried into a thin uniform layer. The deposition of the particle solution can be achieved through an electro-spray or printing method.
In either case, the final nano-composite polymer layer 20 is allowed to air dry and is then peeled off and attached to the desired product through an adhesive backing 30 or other methods known to those skilled in the art to form the completed taggant 40.
Integration of the Taggant into the Product
The matrix that the different classes of materials are incorporated into may include various forms. The matrix of the taggant 40 can be, but is not limited to, the form of: a polymer nano-composite layer, inks, and thin transparent films with adhesive backing. The taggant can be applied to the product in various ways such as:
The taggant 40 in the form of an “ink solution” is mixed with the components of the product itself while being manufactured or produced. For example, the final product can be sprayed with, or dipped into the “ink solution”. An electro-spray technique can be used to uniformly deposit the “ink solution” onto the desired product. In addition, the “ink solution” can be deposited on the surface of the product through a simple printing method.
As note above, if the taggant 40 is in the form of a thin nano-composite polymer layer 20, it can be attached onto the surface of the desired product through an adhesive backing 30 or other ways known to those skilled in the art.
The taggant 40 may also be integrated into a bar code label.
These are only some of the methods through which the security taggant 40 is integrated onto or into different types of products, but it is certainly not limited to the methods described herein, as other ways known to those skilled in the art exist.
As shown in
The nano/micro/bulk particles utilized in the taggant have various physical and chemical properties that produce a unique signature under various modes of detection. For example, an ultraviolet (UV) light will trigger a fluorescent response from nano particles (quantum dots), and the signature will vary depending on the varying dimensions of the nano particles. When quantum dots are utilized as fluorescent taggants, the taggant can thus be optically authenticated. Depending on their sizes, composition and structure, quantum dots fluoresce in different colors providing a unique identification code. The different type and sizes of the quantum dots can be mixed and rearranged in such a way that an extremely large variety of distinctive authentication codes can be generated. Similarly, fluorescent properties may be incorporated into the taggant using fluorescent dyes. Also, particles having other properties, such as magnetism, may be coated with fluorescent materials.
Some particles may have thermal properties so that when excited, for example optically, give off a thermal signature that can be detected by an infrared (IR) camera.
A handheld spectroscopic device with a quick time response can be used to detect the presence of particles present in the taggant. Raman spectroscopy is a very powerful and sensitive technique used to characterize different types of materials. Since each nano/micro particle gives a unique Raman spectrum or has a so called specific “fingerprint” region, Raman Spectroscopy is an ideal technique to authenticate a taggant incorporating nano/micro particles. By varying the concentration, the size and the amount of nano/micro particles, one can generate an extremely large number of Raman spectrums that would be virtually impossible for counterfeiters to reproduce, hence making it practically impossible to replicate the taggant. Each Raman spectrum effectively represents a unique identification code present in the taggant.
In addition, a detection instrument may provide a code/color detection which demonstrates if the taggant is authentic or has been tampered with. The spectroscopic instrument may compare the observed spectrum from a taggant with a stored authentic spectrum. For example, the spectroscopic instrument may use the colors green/red (on the device) to indicate if the taggant is authentic/not authentic respectively. Such verification can be accurately achieved in a matter of minutes.
Therefore, the taggant of the present invention can be easily and quickly verified by a simple instrument, for example, a small UV light, as well as a more complex handheld instrument, such as a Raman spectroscope. The complex nano-tag of the present invention is customizable, inexpensive and amendable to mass production. In addition, it has a variety of applications—it is capable of horizontally spreading across different industries, with only minor changes taking place to the design of the taggant. The size and structure of the taggant can be changed depending on the properties of the surface of the product it will be applied to.
The taggant may be provided with the capability to detect gaseous, acoustic, liquid or solid materials or conditions. These detection functions may be associated with anticounterfeit functions in the taggant or the anticounterfeit functions may not be present.
The nanomaterials incorporated into the taggant could include carbonaceous nanostructures (carbon nanotubes with one, two or multiple walls, nanofibers, graphene layers, or graphite), metal nanoparticles (Au, Ag, Ti, etc.), metal oxides, ceramics, polymeric nanostructures and/or a combination of such materials or classes of materials. In one embodiment, Ag or Au nanomaterials may be coated onto the surface of other structures or nanostructures in the taggant in such a combination that they will provide spectroscopic enhancement of the signal (Surface Enhanced Spectroscopy).
Under the right stimulation (electrical, magnetic, acoustical or optical), the system will provide a detectable signal that is unique and can be associated with a particular product. These structures may be functionalized with various functional groups such as NO2, NH3, COOH, or the like. The nanostructures may be in intimate contact with polymeric structures and/or organic dyes. Under the right electrical, optical or magnetic stimulation, there is a charge transfer from environmental materials such that parts or the whole system will respond optically. The system, composed of one or a multitude of components, therefore acts as a detector for other materials or conditions (gaseous, acoustic, liquid or solid) such as organic and non-organic structures and produces a detectable signal. This can occur under electrical, optical, or magnetic stimulation.
All these systems may be placed on the outside of a product or may be incorporated into the product. These systems can be used inside public or commercial places for detection of organic/inorganic molecules. They can also be placed in transportation vehicles or containers.
The present invention has been described with reference to certain preferred and alternative embodiments that are intended to be exemplary only and not limiting to the full scope of the present invention as set forth in the appended claims.
This application claims the benefit of U.S. Provisional Patent Application No. 61/190,936 filed Sep. 4, 2008, the disclosure of which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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61190936 | Sep 2008 | US |