JP2003511667A - Identification and verification methods - Google Patents

Abstract

(57) [Summary] An apparatus and a method containing one or more kinds of identification additives intrinsic or external to the substance or the product (11). Identifying additives are detected by X-ray fluorescence (20, 21) to identify or verify the substance or its production point. Multiple identification additives are created or identified as part of the substance for the purpose of later verifying the presence or absence of these elements by X-ray fluorescence to determine the unique elemental composition of the identification additive within the substance. Additives are coated on the substance, placed in the label or added to the substance.

Description

Detailed Description of the Invention

RELATED APPLICATION This application is a continuation-in-part of US Provisional Application No. 60 / 157,573, the disclosure content of which is incorporated herein by reference.

FIELD OF THE INVENTION The present invention relates generally to devices and methods for identifying and verifying substances. More specifically, the present invention relates to an apparatus and method for detecting an element or compound which is inherent or incidental to a substance or product, that is, intrinsic or extrinsic, using fluorescent X-rays for identification and verification. .

[0003] BACKGROUND For example explosives, ammunition, paints, devices and methods to identify and validate the various materials or products, such as petroleum products, as well as very high interest in such devices and methods have been materials and documents described Is held. Known methods for identifying and verifying such substances include, for example, addition and detection of substances such as code-generating fine particles, bulk chemical materials and radioactive substances. Other methods for identifying and verifying substances include US Pat. Nos. 6,030,657, 6,024,200, 6,007,
744, 6,005, 915, 5,760, 394, 5,474, 937, 5,
301, 044, 5, 208, 630, 5, 057, 268, 4, 862, 14
3, 4,390,452, 4,363,965 and 4,045,676, etc., the disclosures of which are incorporated herein by reference.

For example, a method of applying a raw material to a substance is also known in order to trace the origin of the substance, the authenticity of the substance, and the distribution of the substance. For example, there is a method of applying a transparent ink to a substance in the visible light region and displaying the presence or absence of this ink by ultraviolet fluorescence or infrared fluorescence. There is also a method in which a microscope additive that can be optically detected is added to the substance. The detection of these substances is mainly based on optical measurement or photometric measurement.

By the way, these raw materials, that is, additives for identification (hereinafter referred to as identification additives)
Many of the devices and methods for identifying and verifying substances using a method have various problems.
For example, methods using these discriminating additives are usually difficult and often time consuming. Also, when analyzing this substance, it is necessary to carry a sample of this substance to a laboratory away from the site. Moreover, the devices for analyzing these substances are often expensive and bulky and difficult to operate. Furthermore, the identifying additive used is a radioactive substance,
It can also harm the human body and cause serious health problems.

Known devices and methods for identification and verification use "line-of-sight" analysis methods, which likewise have some problems. This line-of-sight analysis method requires that the device be "perceptible" to the discriminating additive in order to detect it. For example, if the discriminating additive is placed in the center of a large packet and the packaging and label of the packet "covers" the discriminating additive, the discriminating additive can be used without the need to perceive the discriminating additive. If it is desired to detect it can be a drawback.

[0007] The present invention, in order to identify or verify the manufacturing point of a substance or the substance identified addition of one or more kinds inherent or extrinsic to the substance or the product by X-ray fluorescence analysis Devices and methods for detecting agents are provided. Fluorescent X, where the discriminating additive is manufactured as part of these substances or is placed in a coating, packaging, label or added in the substance, which determines the unique elemental composition of the discriminating additive in the substance. The lines will later verify the presence or absence of these elements.

Since fluorescence X-ray analysis is used, the apparatus and method according to the present invention is simple and easy. At the same time, the device and method according to the present invention provide a device and a method for performing detection by a non-line-of-sight method, thereby ensuring the production place, manufacturing place, reliability, verification or product safety (security) of the material. To do. The present invention is very useful as it is difficult to duplicate, simulate, modify, swap or interfere with. Moreover, the present invention is readily recognizable by the user, either in explicit or concealed form, verifiable by the producer or publisher, and easily applied to various forms of media within a substance. be able to.

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the identification and verification method according to the present invention will be described in detail. Hereinafter, the present invention will be described with reference to specific examples for a complete understanding of the present invention, but those skilled in the art will not limit the present invention to these specific examples. You can understand. Indeed, the present invention may be practiced by modifying the apparatus and methods shown herein and may be used with apparatus and techniques conventionally used in the art.

The present invention uses X-ray fluorescence analysis to detect at least one discriminating additive inherent or incidental to a substance or product. In X-ray fluorescence (XRF) analysis, X-rays are generated by shifting the electrons present in the inner electron shells of the atoms of the discriminating additive, and the shape of the substance to be analyzed (chemical bond). ). The X-rays produced from each element show specific unique spectral characteristics that allow the determination of whether a particular discriminating additive is present in a substance or product.

FIG. 1, 2a and 2b are diagrams showing an outline of generation of XRF.
FIG. As shown in FIG. 1, primary gamma rays, or X-rays 40, are emitted to a sample of target material 46 of material 42. At this time, the secondary X-ray 44 is the target material 4
Emitted from 6 relevant samples.

FIG. In 2 a and 2 b, the atom 48 of the identification additive existing in the target material 46 has an atomic nucleus 50 and electrons 52 discretely existing at a position separated from the atomic nucleus 50 by a specific distance (called an electron shell). Each electron shell has a level of binding energy equal to the amount of energy required to move an electron from the inner shell to the outer shell. The innermost electron shell is the K shell and has the highest level of binding energy corresponding to this K shell. The electron 54 exists in the K shell 56.

The primary X-rays emitted to the atoms 48, namely the gamma ray photons 40, have a predetermined energy. If the energy is greater than the binding energy level of the K shell 56, the energy of the X-ray 40 photon is absorbed by the atom 48 and one of the two electrons in the K shell 56 is absorbed.
Two electrons (ie, electrons 54) are emitted. Thus, when electrons 54 are “vacant” in the K shell 56 due to the emission of the electrons 54, the atoms 48 are activated and become unstable. To become stable, the voids in K shell 56 need to be replenished with electrons, such as electrons 58 present in L shell 60, which have a lower binding energy level. When the electrons 58 of the L shell 60 are replenished in the space inside the K shell 56, the atom 48 becomes
Emit secondary X-ray photons 44. The energy level (or corresponding wavelength) of the secondary X-ray photons emitted in this way is unique to each discriminating additive, allowing the determination of whether or not a particular discriminating additive is present. To do.

At least one type of identification additive is internal or external in the product to be inspected (target material). When one or more types of discriminating additives are present, the discriminating additives are at least part of the constituents of the target material (as elements, compounds or other types of compounds). When one or more kinds of identification additives are present, the identification additive is added or inserted inside the target material, as described below.

The at least one discriminating additive used in the present invention may be any suitable discriminating additive known in the art. For example, US Pat. No. 5,474,937, 5,760, the disclosure of which is incorporated herein by reference.
Suitable identification additives include any element or compound detectable by XRF, as described in 394 and 6,025,200. The type of element that can be used as a discriminating additive may theoretically be any element listed in the periodic table, but the low energy released by an element with a small atomic number is limited. It can be a factor. This type of low energy can easily be reabsorbed by its own matrix or, in some cases, the surrounding environment (eg, air). Further, various different isotopes of an element and elements that "excite" only under specific conditions, such as a specific temperature range, can also be used as discriminating additives in the present invention. As the identification additive usable in the present invention,
All elements with atomic numbers 6 to 94 can be mentioned. In the present invention, it is preferable to use a rare earth metal as at least one kind of the identification additive.
Further, in the present invention, it is more preferable to use gadolinium (Gd) or yttrium (Y) as at least one kind of the identification additive.

The type of identification additive is determined by the target material in which the identification additive is present. As described below, the target material can interfere with XRF detection during XRF analysis because backscattering and peaks from the target material composite interfere with peaks of the discriminating additive. For example, when the paper contains an arsenic (As) discrimination additive or the paper contains a very small amount of Pb, the K level electron and Pb of As are detected during XRF detection.
L-level electrons of may confuse the reading.

In one embodiment of the present invention, the type of discriminating additive must be selected based on the ability of the substance to be arranged (eg, coated) to contact or adhere to the discriminating additive and / or the target material. I won't. In most cases, the target material will be used very frequently, treated and / or cleaned. In such a state, when the identification additive (or the substance containing the identification additive) is removed from the target material, there is little value in adding the identification additive to the target material. For example, when a thin film or coating (eg, ink) containing the identification additive is added to the target material (eg, paper), the identification additive and the coating method are selected so as not to be removed due to frequent contact with the hand, for example. Must. In view of such conditions of the present invention, the method of addition and / or the discriminating addition such that the paint is added in chemical contact with the target material, for example, as when the paint is applied and deposited on the wall. The agent is preferably selected.

In another embodiment of the present invention, the type of discriminating additive depends on the ability of the substance to have the discriminating additive placed (ie, added) such that it is removed from the discriminating additive and / or the target material. It is possible to make a selection based on In many cases, the purpose of adding the discriminating additive to the target material is temporary. Therefore, once this objective is achieved, the discriminating additive is no longer needed and can be removed at any time. For example, if an identification thin film or coating is added to the target material, once the target material is identified, these identification thin films or coatings are no longer needed and may be removed by any suitable means. In view of such circumstances of the invention, it is preferred that the coating and / or discriminating additive be selected to be removed by mechanical or chemical means.

The amount and concentration of the identifying additive in the target material also varies depending on the element number used and the energy required. The amount of discriminating additive used in the present invention is determined by the minimum amount required for XRF detection. Further, as described below, it is possible to additionally use a discriminating additive. The concentration of the discriminating additive is at least about 1 ppm
And the concentration can be varied from about 1 to 100 ppm. It is possible to further increase the amount of the discriminating additive, but a small amount of discriminating additive will suffice as the amount of discriminating additive is increased. If the identification method using the XRF device and the XRF device is improved, the concentration of the identification additive is further lowered (that is, less than 1 ppm).
You can also do it.

Further, the shape of the identification additive in the target material also changes. The shape of the identification additive is
Any large or small compound (including elements added by itself or other components (
That is, a salt) or a molecule. In fact, the discriminating additive can be a combination of various components and / or additives that make up the mixture and / or solution. These other components or additives may be used for various purposes such as, for example, modification of XRF properties, modification of the ability to be added to a substance / product, stabilization of a mixture or solution, or other purposes known in the chemical arts. It can be selected according to the purpose.

In one embodiment of the present invention, the at least one discriminating additive is a combination of discriminating additives, ie a plurality of discriminating additives. The plurality of identification additives also include a plurality of identification additives of the same type, such as the same element or compound. The combination of discriminating additives can also be multiple types of discriminating additives, eg different elements or compounds in different media. For example, when the identification additive dispersed in the ink is added to the paper, the paper may also contain the same or different identification additives. As described above, the plurality of identification additives may be a combination of at least one kind of intrinsic identification additive and at least one kind of external identification additive.

At least one identifying additive added to the target material is capable of producing a unique code. Such a code indicates the number and type of discriminating additives present or absent, the isotopic abundance (ie concentration) of the same or different discriminating additives, the position of the discriminating additive within the substance (ie , A bar code created by a series of discriminating additives with spaces, where the spaces are part of the code), generated based on the presence of a complex type or complex shape of a single discriminating additive or combinations thereof. To be done.

As an example of this type of code, the present invention comprises a system for controlling the concentration of one type of discriminating additive in a target material to produce a unique code. For example, yttrium oxide can be used as an identifying additive to add (tag) to 10 batches of commercial carpeting. Next, various concentrations (ie 10p)
pm, 20 ppm ,. ． ． , 100 ppm) of the discriminating additive is added to produce 10 unique codes for these 10 batches.

The number of unique codes with only one single discriminating additive is determined by the precision with which the concentration in the sample can be controlled and measured. For example, about 10p
Easily create 10 (ie 10 ppm, 20 ppm, ..., 100 ppm) unique codes for a concentration range from a single discriminating additive using a method that allows concentration increments per pm You can For example, additional signs can be created for even larger concentration ranges, such as 100 signs can be created that vary from 10 ppm to 1000 ppm in 10 ppm increments. Also, by using better density and detection methods (eg smaller increments), more codes can be created.

Furthermore, the number of unique codes can be increased by adding the type and concentration of the same or different identifying additives. Moreover, the number of codes can be significantly increased by using a plurality of identification additives when creating the codes. For example, the number of codes can be increased by adding another discriminating additive with a unique concentration. The number of codes can be further increased by adding a third discriminating additive with a unique concentration. In this way, it is possible to increase the number of codes by adding the identification additive. This encoding scheme is determined by the concentration increment of each discriminating additive.

In this coding scheme, the number of codes that can be used can also be increased by changing the position of one or more types of discriminating additives in the substance to be detected. For example, the detected substance can be divided into arbitrary parts (that is, quadrants) in which the discriminating additive (or code) is distributed, and the number of codes is increased in the parts other than these parts during XRF analysis. Can be made.

Contamination of the identification additive can occur if the identification additive contains an element or compound that may be present in the target material or in the environment in which the target material is placed. As a result, reading the identification additive code can also be difficult. For example, if yttrium oxide is included in the discriminating additive and is also present in the carpet as a target material, the discriminating additive's presence as a result of environmental pollution, internal chemical reactions or other contamination. The additional amount appears in the target material. If such contamination occurs, there should be a change in the concentration of the identifying additive in the target material. The measured value of the discriminating additive at this time may show a value corresponding to an erroneous sign.

In such a case, compared to the identification additive that was present before the contamination occurred,
It is difficult to determine how much discriminating additive amount is present in the target material as "contamination". This problem is, for example, a backup or a second identifying additive, a backup or a second code, or a backup or a second location.
By using a backup (i.e. copy or otherwise) or a second system, such as is possible in target materials that may be contaminated. For example, U.S. Pat. No. 5,600, the disclosure of which is incorporated herein by reference.
, 760,394. Multiple backups or secondary systems can be used if desired. Backup or second system for other purposes,
It can also be used, for example, to verify the original coding system.

Any suitable target material can be used in the present invention. Suitable target materials are substances which inherently contain the discriminating additive or substances to which the discriminating additive can be added. XRF detection measures changes in the inner electron shell of the discriminating additive and is not significantly altered by the chemical reactions that normally occur in the outer electron shell. Therefore, it is possible to identify and add chemicals and to retain the identifying additive code in products made with these chemicals. The discriminating additive must be composed of a material that facilitates XRF detection with little chance of causing, for example, background contamination, discriminating additive degradation, discriminating additive destruction, or other contamination or deterioration therein.

Suitable target materials include, for example, paper products such as documents, banknotes and tickets;
Solid products such as jewelry, carpets, packaging (thin films, labels and adhesives) metal, rubber (tires), wood and plastics (credit cards); liquids such as lubricating fluids, resins, sprays, paints, oils and inks Includes products; hazardous wastes; drugs or agents; gaseous products; combinations or hybrids of these substances. In addition, suitable target materials, such as paper documents, drugs or counterfeit items, include substances that have been subsequently modified. For example, a target material that may be destroyed can be identified and added by an element known to be present in the residue due to the destruction. Since the identification additive is generally unchanged by the chemical treatment by destruction, the connection between the target material and the residue can be connected after destruction. The target material used in the present invention is preferably a carpet material or a carpet product.

Target materials containing at least one discriminating additive can be used in numerous applications. For example, the identification additive paint allows identification of any substance coated with the paint. As another example, paper and ink containing identification additives used in (or applied to) paper can be used to establish the authenticity of documents and banknotes. In yet another example, many manufactured items that can be counterfeited or plagiarized can benefit from the identification addition. The addition of an identifying additive to the threads used in garments can be used to encode information regarding manufacturing date, time and location. The addition of identification additives to the raw materials used in the manufacture of this type of product such as compact discs, computer discs, videotapes, audiotapes, electronic circuits and other products can lead to plagiarism and counterfeit cases related to these products. Useful for tracking and litigation.

According to the present invention, at least one discriminating additive can be added in the target material in any suitable form. Suitable forms include the addition of the identifying additive within the target material with little or no damage (either chemical or physical) to the target material. For example, US Pat. Nos. 5,208,630, 5,760,394 and 6,030,657, the disclosures of which are incorporated herein.
See issue. Other suitable forms include the use of particles such as microparticles; solvents; coatings and films; adhesives; sprays; or substances containing discriminating additives such as hybrids or combinations of these methods. . In any of these forms, at least one discriminating additive is added alone or with other agents.

At least one discriminating additive can be added to the target material using any suitable method. Many existing identification addition methods relate to the use of microparticles comprising an element, compound or complex of elements with at least one identification additive. In addition, particles can be made where the smaller particles, compounds or complex of elements include the discriminating additive. Next, the material of this type of particle is shown. That is, magnetic or fluorescent materials that are easy to collect, refractory materials that enhance the persistence of particles in explosions, or chemically inert materials that enhance the persistence of particles in chemical reactions. In fact, particles of this kind are composed of non-durable, soluble or reactive substances in order to enhance the dispersibility of the discriminating additive in fluid, aerosol or powder systems.

When the target material is a liquid substance such as paint or ink, an adhesive or a liquid substance having a liquid component, at least one kind of the identification additive is added as an element or a compound in a solution with the liquid. It is possible to Thus, at least one discriminating additive may be added in elemental or compound form suspended in a solution or target material. When the solvent evaporates, the at least one discriminating additive is dissolved or suspended in the solvent used to prepare the target material so that the remaining residue contains at least one discriminating additive. It is possible.

It is possible to add the identifying additive into the target material of the substance either during or after the production of the substance (or part thereof). The discriminating additive can be manufactured as a component of the substance or as part of the component of the substance. When manufacturing the identification additive,
The at least one discriminating additive can also be added within other substances, including parts of the target material. Indeed, the at least one discriminating additive may be an element or compound of the target material itself. The identification additive can be added to any position of the substance (including the surface). The two-dimensional (and three-dimensional) shape and pattern of at least one discriminating additive can be configured in any combination with respect to the type and number of discriminating additives.

The at least one identification additive can be added even after the production of the target material of the substance. The identification additive can be deposited within the material as an implant or as a coating or film on the material. Furthermore, at least one kind of identification additive can be added as an impurity (dopant) in the already formed target material.

The at least one discriminating additive can be physically or chemically deposited by itself as a coating or film. The at least one discriminating additive can be added as one component (or contaminant) of another substance (such as a mixture or solution) that forms a coating or film. In an embodiment of the invention, the at least one discriminating additive is a solution (using a liquid applied to the substance, for example a spray).
Alternatively, it can be added as an element or compound in a suspension). Upon evaporation of the solvent after it has been applied to the material, the at least one discriminating additive is soluble or suspendable in the solvent such that the residue left behind comprises the at least one discriminating additive.

As is apparent from the above description, the present invention can be easily identified and added to a small batch of target material by using a code unique to the batch. This can be done in a manual or automated system and each batch (or selected batch) is given a different code. For example, when making 1000 (or 100) compact discs, each disc may range from 1 to 1000 (or 1).
To 100) can be used to identify and add. However, the minimum size of each batch and the number of batches that can be separately added may be limited from the economical and processing viewpoints.

As mentioned above, any product or substance as a target material can have at least one extrinsic or intrinsic distinguishing additive located therein. For example, the target materials of the present invention are carpeting and carpet products.
Generally, carpet is composed of both yarn and backing. The yarn is bound or secured within the backing in various ways, affecting the feel and durability of the carpet. Weaving yarns are composed of different types of materials, generally fibers, and different types of twists and shapes of fibers are used to change the appearance of the carpet. The fibers can be made of nylon, polypropylene, polyester, acrylic, wool or combinations thereof. The components of the carpet and methods of making them are known in the art. See, for example, US Pat. No. 6,030,685, the disclosure of which is incorporated herein.

In the present invention, at least one discriminating additive is added into the carpet yarn or backing by any suitable method. For example, at least one identifying additive is added within the fibrous material during preparation of the fibrous material. Also, in another embodiment, at least one discriminating additive is added within the individual fiber materials.
During the subsequent twisting process, the fibrous material is woven into yarn (without any identifying additives). In yet another embodiment, at least one discriminating additive is added during the making of the backing.

At least one identifying additive is also added as a coating or film to the carpet yarn or backing. For example, it is possible to coat the yarn and / or the backing with at least the discriminating additive after the yarn or the backing has been made and before weaving them together. In another embodiment, the carpet fabric is sprayed with a protective coating to further facilitate cleaning and at least one discriminating additive is added within the protective coating. In yet another embodiment, the carpet fabric is dipped in a protective dressing containing at least one discriminating additive and then dried,
A protective coating containing the identifying additive is left on the carpet as a thin film. It is preferred that the film containing the identifying additive be chemically attached or adhered to the fibers and / or yarns of the carpet so that the film is not easily removed from the carpet during steaming or cleaning.

At least one identifying additive is added into the carpet product for each batch that has the sign of the carpet itself. The discriminating additive is added into the fiber raw material (ie nylon) before the fiber is made from the raw material, either as a solid (ie particulate) or as a liquid (eg solvent) containing at least one discriminating additive. By doing so, it can be added into the yarn fiber. Fibers are made from nylon,
The next time the yarn is twisted into a yarn, the yarn will include at least one identifying additive. Assuming that two types of discriminating additives are used, it is possible to incorporate multiple automated reservoirs containing these two discriminating additives in varying concentrations into the assembly line process. . Each reservoir has, for example, 5
/ 5, 5/10, 5/15 ,. ． ． 10/5, 10/10, 10/15 ,. ． ．
95/85, 95/90, 95/95, etc., containing a distinguishable mixture of different concentrations of the discriminating additive. As the sample of yarn fiber raw material passes through the assembly line, it receives the identifying additive from the desired reservoir. Thus, each yarn made from this material receives a unique combination of identifying additives.

After the state in which at least one kind of the identification additive is extrinsically or intrinsically present in the target material, FIG. One or more types of identification additives are detected to identify or verify the target material using XRF analysis as shown in 1. Primary X-rays 40 are used to excite the sample of target material 46, and secondary X-rays 44 emitted by the sample are detected and analyzed.

FIG. As shown in FIG. 3, X-rays of various energies are detected. For example, there is a broad band formed by scattered X-rays with energies less than and greater than the energy of atoms in the excited state. The spectrum when paper is used as the target material is shown in FIG. 3 shows. Within this broad band are peaks due to the excitation of one or more discriminating additives in the sample. The ratio of the radiant intensity of any peak to the radiant intensity of the background at the same energy (known as the background-to-peak ratio) is a measure of the elemental concentration with a characteristic X-ray at the peak energy, such as a discriminating additive. .

In the position embodiment of the identification method according to the present invention, at least one target material is selected that contains one or more types of identification additives to be identified whose concentration is already known. X-ray radiation source (“source”), X-ray radiation detector (“detector”)
An XRF analysis of the target material (or a sample thereof) is carried out using a detection device, which comprises a support means, an analysis means and a calibration means.

One embodiment of the detector according to the present invention is shown in FIG. 4a. FIG. As shown at 4a, the detector 25 comprises a conventional fluorescence X-ray spectrometer capable of detecting the elements present in the coating, package or substance. X-rays 29 from a source (eg, either an X-ray tube or a radioactive isotope) 20 are emitted to the sample 11. At this time, the sample 11 absorbs the emitted X-rays and emits X-rays 31 toward the X-ray detector 21 and the analyzer 23 capable of discriminating the energy or wavelength. This can be done, for example, by Edax (Mahwah, New J
X such as Edax DX-95 or MAP-4 portable analyzer manufactured by ersey)
Achieved using a line spectrometer. The analyzer 23 part is the computer control system 2
7 is provided.

Another embodiment of the detector according to the present invention is shown in FIG. 4b. FIG. As shown in 4b, the detector 25 comprises an instrument housing 15 having various components. Gamma rays or X-rays 30 from a source (eg, either an X-ray tube or a radioactive isotope) 20 are focused by the aperture 10 and emitted to the sample 11. Sample 11 contains at least one discriminating additive that absorbs radiation and emits X-rays 31 towards X-ray detector 21. The analysis means may optionally be incorporated within the housing 15.

Here, the present invention relates to FIG. It is not limited to the detectors shown in 4a and 4b. The source for this detector can be any suitable source or sources known in the art. See, for example, US Pat. Nos. 4,862,143, 4,045,676 and 6,005,915, which are incorporated herein. During the XRF detection process, the source emits a high energy beam at the discriminating additive. The beam may be an electron beam or electromagnetic radiation such as X-rays or gamma rays. Therefore, the source can be any substance that emits a high energy beam of this kind. Generally, these are X-ray emitting devices such as X-ray tubes or radioactive sources.

In targeting, the beam can be properly focused and directed by any suitable means, such as an orifice or aperture. The configuration of the beam (size, length, diameter ...) is determined by the desired X, as is known in the art.
Controlled to achieve RF detection. Source power (or energy level)
Also must be controlled to achieve the desired XRF detection, as is known in the art.

The one or more sources can be shielded and emit radiation into the space defined by the state of the shield. Therefore, the shields, configurations, and materials used to shield the source must be controlled to maintain XRF detection consistency.
Any suitable material and composition known for shielding known in the art can be used in the present invention. Preferably, a high density material such as tungsten or brass is used as the shielding material.

Any suitable detector or detectors known in the art can be used as the detector in the detector of the present invention. For example, US Pat. Nos. 4,862,143,4, the disclosures of which are incorporated herein by reference.
, 045,676 and 6,005,915. Any type of substance capable of detecting the photons emitted by the discriminating additive can be used. Traditionally, silicon and CZT (cadmium-zinc-telluride) detectors have been used, but other detectors such as proportional counters, germanium detectors or mercury iodide crystals can also be used. .

The detector's must be controlled to provide the desired XRF detection. First, the geometry between the detector and target material must be properly controlled. XRF detection also relies on the detector body, configuration and materials such as tungsten and beryllium used as windows to allow the emission of X-ray photons to the detector. In addition, detector aging, voltage, humidity, changes in exposure, and temperature also affect XRF detection, so these conditions must also be controlled.

The analysis means classifies the radiation detected by the detector into one or more energy bands and measures its intensity. Therefore, any analysis means having such a function can be applied to the present invention. The analysis means may be a multi-channel analysis device for measuring the radiation detected in the characteristic bands and other bands necessary for calculating the value of the characteristic radiation which is distinguished from the scattered or background radiation. For example, US Pat. No. 4,862,1 the disclosure of which is incorporated herein by reference.
43, 4,045,676 and 6,005,915. XRF also depends on the resolution of X-rays. Background noise and other noise contained in X-rays must be filtered in order to make accurate measurements. For example, the signal must be separated into a suitable number of channels and excess noise must be removed.
Resolution can be improved by cooling the detector with a thermoelectric cooler such as nitrogen or Peltier coolers and / or filtration. Another way to improve this resolution is to use a preamplifier.

The support means supports the source and the detector arranged at a predetermined position with respect to the sample of the target material irradiated with X-rays. Therefore, any supporting means having this function can be applied to the present invention. In one embodiment, the support means comprises two housings, a first and a second housing, the source and the detector being located within the first housing, the first housing comprising the FIG. As shown at 4a, it is connected by a flexible cable to a second housing in which the analysis means are arranged. If desired, the first housing can be handheld. In other embodiments, the source and detector and other components of the detection device are as shown in FIG. It is placed in one single housing as shown at 4b.

Calibration means are used to calibrate the detector to ensure the accuracy of the XRF analysis. During the calibration by the calibrating means, the various modifiable and measurable parameters are separated and calibrated. For example, geometric conditions or configurations can be separate and calibrated. In another example, the substance matrix is separated and calibrated. As the calibration means in the present invention during the detection period, it is preferable to perform internal (natural) calibration.
Components such as tungsten shields already exist for internal calibration during XRF analysis. Other methods such as fluorescent peaks or Compton backscattering can also be used for internal calibration in the present invention.

The analysis means comprising the computer control system 27 is connected to the X-ray detector 21 and receives and processes the output signal from the X-ray detector 21. The energy range targeted for identification, including the energy levels of the secondary X-ray photons 44 emitted by one or more identification additives, is divided into several energy subranges. The computer control system 27 uses a specific software program, such as a program for analyzing detection and X-ray interactions and a program for analyzing backscatter data, to detect the X-ray photons detected in each subrange. Continue counting counts. After a predetermined exposure time, the computer control system 27 displaying the menu stops receiving and processing the output signal and produces a graph of the counts associated with each subrange.

FIG. 5 is a representative graph of the counts associated with each subrange. This graph is essentially a histogram representing the frequency distribution of the detected X-ray photon energy levels E1, E2 and E3. Peaks in the frequency distribution (where the counts are relatively high) occur at the energy levels of scattered primary X-ray photons as well as secondary X-ray photons from one or more discriminating additives. Primary X incident on target material
Line photons are either absorbed or scattered. The desired secondary X-ray photons are emitted only when the primary X-ray photons are absorbed. The scattered primary X-ray photons that reach the detector of the system form unwanted background intensity levels. Therefore, the sensitivity of XRF analysis is determined by the background intensity level, and the sensitivity of XRF detection can be improved by reducing the amount of scattered primary X-ray photons reaching the detector. The peaks that occur at the energy level of the scattered primary X-ray photons are essentially ignored, but the other peaks that occur at E1, E2 and E3 are for identifying at least one discriminating additive present in the target material. Used for.

In the process of XRF detection, in addition to the parameters mentioned above, at least two other parameters have to be controlled. First, the medium (eg air) through which gamma rays (and x-rays) have to travel is subject to XRF as well. Therefore, different types of media must be considered during XRF analysis. Second, the methods used for X-ray interpretation and analysis are largely determined by the algorithms and software used. Therefore, these methods must be configured to use software and algorithms that consistently perform XRF detection.

These two parameters and those mentioned above must be carefully handled and controlled in order to make accurate measurements. In one embodiment of the invention, these parameters can be modified and controlled to produce another different code. For example, one different code can be generated with a particular source and a particular detector using a particular measurement geometry and a particular algorithm. By altering the source, detector, geometry or algorithm, it is possible to generate a new set of totally different and different codes.

FIG. FIG. 6 is a diagram for explaining an identification device and a detection method according to the present invention. FIG. As shown in 6, the detector 25 is capable of detecting at least one discriminating additive present in the target material 10, such as a carpet sample. The detector 25 is a small portable device that can be fully operated manually. The detection and locator device 25 is portable and allows for further miniaturization by including all the above-mentioned components (ie source, detector, analysis means and calibration means) in a single housing. .

The present invention is in no way limited to any particular XRF analysis. Any type of XRF can be used in the present invention, for example, total internal reflection fluorescence X-ray (TXRF).

In one embodiment of the invention, once a substance has been subjected to a discriminating addition, the device and method used discriminate the substance. The ability to add invisible identification additives to substances, and in particular to identify by non-line-of-sight methods, provides a valuable device and method to certify, validate, track, label or distribute any type of merchandise in any industry. Should do. In addition, one or more invisible identification additives can be used to prevent duplication and counterfeiting of merchandise. In another embodiment of the invention, the device and method according to the invention can be used for the same purpose, except in the case of products in which the desired identification additive has already been added to the product. Thus, the present invention is able to pinpoint the exact location of one or more contaminants within a substance via analysis of liquid streams or three-dimensional analysis for contaminant particles.

[0063]   Hereinafter, a non-limiting example of the identification and verification method according to the present invention will be shown.

Example 1 Carpet as a sample was purchased and cut to a size of 4 inches x 4 inches. One liter of protective liquid was also purchased from a vendor.

Next, 1 liter of distilled water and 162.7 grams of yttrium oxide were mixed into a homogeneous solution to make a discriminating additive solution. The concentration of the discriminating additive in the discriminating additive solution was 14% by weight.

Next, 0.054 milliliters of the discriminating additive solution and 4.5 milliliters of the protective liquid were mixed to make a homogenous solution of the "discriminating" protective liquid. The yttrium oxide concentration in the discriminatingly added protective liquid was 0.014% by weight. The discriminatingly added protective liquid was then diluted with 1 liter of distilled water. A coating of the discriminating protective liquid was then formed on the sample by dipping the sample carpet in the discriminating protective liquid. The carpet sample was squeezed and dried until the liquid of the added protective liquid was evaporated, leaving yttrium oxide as the thin film component covering the carpet yarn and backing. The concentration of yttrium oxide in the carpet was 8 ppm.

Example 2 A carpet sample loaded with the discriminating additive from Example 1 was analyzed for the discriminating additive. FIG. The same handheld detector as the detector shown in 6 was used to detect the presence of the discriminating additive using XRF analysis.

The detector contained several components. A trigger activated tungsten shutter block containing an Americium 241 gamma ray point source and a silicon pin X-ray detector was installed in the front of the instrument. The circuit boards needed to obtain and process the data from the detectors were installed elsewhere in the housing. The instrument includes a red and blue light to indicate if the carpet has an additive additive and an indicator to indicate to the user whether the carpet has an additive additive. A keypad on the top of the detector allows the user to turn on / off the detector's electronic instrument. The keyed lock on the side of the detector prevents the user from inadvertently opening the shutter block to expose the radioactive source.

This detector is based on XRF of carpet as a sample with discriminating additives added.
Used for analysis. FIG. FIG. 7 is a diagram showing a result of XRF analysis of a sample to which a discriminating additive is added. FIG. The peak at 7 indicates the presence of the yttrium oxide discriminating additive.

Although the preferred embodiment of the present invention has been described above, the present invention can be modified without departing from the spirit and scope of the present invention. Therefore,
The invention as defined by the appended claims is not limited by the particular embodiments described above.

[Brief description of drawings]

FIG. 1 FIG. FIG. 1 is a diagram showing an outline of generation of XRF, and is a diagram showing how X-rays are radiated to a target material.

FIG. 2 FIG. FIG. 2a is a diagram showing an outline of generation of XRF, and is a diagram showing how electrons are emitted from electron shells when X-rays are emitted to atoms.

FIG. 3 FIG. 2b is a diagram showing an outline of generation of XRF, and is a diagram showing how electrons are emitted from electron shells when X-rays are emitted to atoms.

FIG. 4 FIG. FIG. 3 is a diagram showing an X-ray spectrum detected when X-rays are radiated onto a paper target material.

FIG. 5: FIG. 4a is a diagram showing a specific configuration of an embodiment of a detector according to the present invention. FIG.

FIG. 6 FIG. FIG. 4b is a diagram showing a specific configuration of another embodiment of the detector according to the present invention.

[Figure 7]   FIG. 5 is a representative graph of counts associated with each subrange.

FIG. 8 FIG. FIG. 6 is a diagram for explaining an identification device and a detection method according to the present invention.

FIG. 9: FIG. FIG. 7 is a diagram showing a result of XRF analysis of a sample to which a discriminating additive is added.

─────────────────────────────────────────────────── ─── Continued front page    (81) Designated countries EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, I T, LU, MC, NL, PT, SE), OA (BF, BJ , CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, K E, LS, MW, MZ, SD, SL, SZ, TZ, UG , ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, C U, CZ, DE, DK, EE, ES, FI, GB, GE , GH, GM, HR, HU, ID, IL, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR, L S, LT, LU, LV, MD, MG, MK, MN, MW , MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, T T, UA, UG, US, UZ, VN, YU, ZW (72) Inventor Watson, David, Jay             Washington, United States 99352             Richland Sanford Avenue               1109 (72) Inventor Mayer, Garhard, A             United States Ohio 43085             Osington Belend Street             6734 F-term (reference) 2G001 AA01 AA02 AA10 BA04 CA01                       GA01 JA04 KA01 KA20 LA20                       NA11 NA15 NA17 RA08 SA01                       SA14 SA15

Claims (18)

[Claims] 1. A method for detecting at least one type of identification additive contained in at least one substance, the method comprising the step of adding at least one type of identification additive to at least a part of the substance, and at least one type. A step of causing the discriminating additive to emit at least one kind of X-ray; and a step of analyzing whether or not the at least one X-ray has a specific energy. 2. The detection method according to claim 1, wherein the at least one substance is at least one carpet. 3. A method of analyzing a substance, comprising: providing a portion of the substance; irradiating a portion of the substance with an energy beam; at least one portion of the substance having a specific energy. Analyzing whether two X-rays are emitted. 4. The method of claim 3, wherein the at least one substance is at least one carpet. 5. A method of coating a substance with at least one discriminating additive, the method comprising: providing a portion of the substance; and emitting at least one x-ray when irradiated with an energy beam. Applying a coating comprising at least one identifying additive to the portion of the material. 6. The material coating method of claim 5, wherein the at least one material is at least one carpet. 7. A coating of at least one substance comprising at least one discriminating additive which emits at least one X-ray when irradiated with an energy beam. 8. The coating of claim 7, wherein the at least one material is at least one carpet. 9. At least one discriminating additive wherein the discriminating additive emits at least one X-ray when irradiated with an energy beam; and the discriminating additive solution is supplied to at least one substance. And at least one solvent that at least partially evaporates. 10. The identification additive solution according to claim 9, wherein the at least one substance is at least one carpet. 11. A method of making at least one substance comprising at least one discriminating additive, the method comprising: providing a portion of said substance; and at least one x-ray when irradiated with an energy beam. Applying a coating comprising at least one discriminating additive that emits to the said portion of said substance. 12. The method of claim 11, wherein the at least one material is at least one carpet. 13. A material comprising at least one discriminating additive, said material providing a portion of said material, and at least one emitting at least one X-ray when irradiated with an energy beam. A material comprising a coating comprising a type of identifying additive on said portion of said material. 14. Material according to claim 13, characterized in that said material is at least one carpet. 15. A material having a coating comprising at least one discriminating additive which emits at least one X-ray when irradiated with an energy beam. 16. Material according to claim 15, characterized in that at least one said material is at least one carpet. 17. A method of adding a discriminating additive to a substance using at least one discriminating additive, the method comprising: providing a portion of the substance; and at least one X when irradiated with an energy beam. A method for adding a discriminating additive, characterized in that it comprises the step of applying a coating comprising at least one discriminating additive which emits radiation to said part of said substance. 18. The method of claim 17, wherein the material is at least one carpet.