WO2016046500A1 - Portable appliance for determining the presence and/or absence of tracers in an object - Google Patents

Abstract

The invention relates to a portable appliance comprising a source (10) for illuminating an object, and means (5, 15-19) for determining the presence and/or absence of tracers in the illuminated object, and consequently deducing correspondence of the illuminated object to a reference.

Description

 PORTABLE APPARATUS FOR DETERMINING THE PRESENCE AND / OR ABSENCE OF PLOTTERS IN AN OBJECT.

The present invention relates in particular to a device for enabling the identification or authentication of a product or a material.

Recycling materials from end-of-life products is essential to preserve our non-renewable resources and reduce our impacts on climate change, human health impacts and ecosystems. Several obstacles to the recycling of materials exist, technical brakes and brakes related to the social acceptability of recycled materials.

There are still several technical barriers to recycling materials from end-of-life products. These products are collected and treated at the end of their life; this leads after grinding to sorting complex mixtures [Reuter, 2005] whereas a product could have been eco-designed. Another obstacle is related to the two types of industrial sorting technologies most representative of the recycling sector which do not make it possible to sort materials by physicochemical sorting such as densimetric sorting when the densities overlap and by NIR fast spectrometric sorting when the polymers are dark in color. In 2009, 24.3 million tons of plastic waste were generated in Europe and only 22.5% on average were recycled, all sectors combined (PlasticsEurope, 2010). The barriers to social acceptability lie in the traceability of toxic substances potentially contained in recycled materials and waste that is found in the seas because they are not recycled.

A proposal is therefore to add a new property specific to the material (signature, marking) that can be detected in order to identify and authenticate the material with a fast automated industrial sorting machine. Tracer / polymer systems were developed from laboratory tests and detection tests were performed to detect the signals from these systems.

The object of the invention is to provide a detection apparatus dedicated to the identification of light or dark colored polymeric materials containing low concentrations of tracers, suitable for dark-colored materials and, for reasons of industrial constraints, particularly suited to fast sorting in 10 milliseconds. These concentrations are preferably less than 1000 ppm and should be detected in black materials. The concentrations are preferably from 0.1 ppm to 1000 ppm. Low concentrations do not alter the properties of the plotted materials, are less expensive and difficult to counterfeit.

To achieve its purpose, the invention provides a portable device characterized in that it comprises means for illuminating an object with an incident light beam, means for analyzing a signal emitted by the object under the effect of the incident beam. The apparatus may further include means for determining the presence and / or absence of tracers in the illuminated object, and preferably means for deriving a code therefrom. It may also include means to deduce a conformity of the illuminated object to a reference and, preferably, alert means in case of non-compliance.

Advantageously, an apparatus according to the invention comprises one or more of the following characteristics:

 - autonomous at the energy level;

 - integration of its computing device, such as a microcomputer;

 wireless communication means, for example of the Wifi or Bluetooth type to simplify, possibly allowing connection to the Internet;

 a photographic module and / or a GPS module, to ensure traceability of the measurements;

 - automatic response, for example an alert in case of non-compliance;

- can be coupled or integrated with an alert system (quality assurance) or backup / control information locally or on the Internet;

 - no moving part, except possibly a trigger switch on; programmable, in particular according to the matrices or tracers to be detected, and adjustable according to the purity or the desired grade, in particular for setting a confidence index, for example 95%;

a source of excitation chosen for a long lifetime, preferably several thousand hours;

- Sensitive, even at very weak signals: detection of tracers even at very low concentrations, for example from a few hundred to a few fractions of ppm;

means for processing the signal emitted by the object, enabling the identification of tracers in highly colored or black-black matrices; - ability to identify not only packaging type objects but also small areas such as labels, capsules, chips, particles or powders. An object of the invention is in particular to identify objects, particles or materials, automatically, and to deliver a fluorescence signal that will authenticate the materials, products and who may be able to notify an alert, by example for a quality control, in case of nonconformity.

Several embodiments of the invention will be described below, by way of non-limiting examples, with reference to the appended drawings in which:

- Figure 1 is an elevational view of an embodiment for an apparatus according to the invention; and,

 FIG. 2 is a diagram illustrating the components and the operation of the device of FIG. 1.

Figure 1 is an elevational view of an apparatus 1 according to the invention. In the illustrated example, the apparatus is a spectroscope is a compact and ergonomic system, without moving part; it is portable and suitable for use in post-production for the quality control of materials or against counterfeiting.

As illustrated in FIG. 2, this apparatus comprises a barrel 2 extending forwards and intended to illuminate an object 10 (see FIG. 2) to be analyzed by means of an incident light beam 13, then to collect a light signal 14 emitted by the object under the effect of the incident ray. It further comprises a handle 3 provided to hold the device with one hand. The handle is equipped with a trigger 4 designed to be operated with the index finger of the hand holding the device. The trigger, when depressed, causes the device to operate.

A calculator 5 makes it possible to transform the collected analog data into digital data. In the illustrated example, a USB key 6 is connected to a USB socket of the computer 5, in order to transmit this data to a computer, preferably portable. The device operates from the power provided by the USB ports of the computer. In an improved embodiment, the apparatus is self-powered, preferably with a rechargeable battery. Likewise, the computer comprises means for wireless transmission of the data collected to the computer, if necessary. In the case of an apparatus provided for the authentication of the object, it advantageously comprises display means, for example a screen for displaying "true" when the object and authentic or "false" otherwise.

As illustrated in FIG. 2, an apparatus 1 according to the invention comprises:

 a source or several sources 11, 12, for example ultraviolet (UV) or infrared (IR) to provide an incident ray (13);

 a system 15-19 for detecting a fluorescence signal (visible, IR, UV)

a signal processing system 5 for identifying the polymer-tracer system

A source 11 may be polychromatic or monochromatic:

- For UV it can be chosen from lasers, laser diodes, light-emitting diodes, gas tubes such as a xenon lamp or mercury lamp, operating in pulsed or continuous mode, provided or not with a reflector or condenser, with or without filters, for example interferential to select the right excitation wavelengths of the tracers and provided with or without optical fiber to transport the radiation.

 - For IR it can be chosen among lasers, laser diodes, light-emitting diodes, lamps such as filament lamps, operating in pulsed or continuous mode with or without a reflector, a condenser , provided or not with filters for example interferential to select the right excitation wavelengths of the tracers and provided or not optical fiber to carry the radiation.

The source 11 may also be designed to emit microwaves and / or X-rays, suitable for the analysis of last generation tracers.

In the example illustrated in FIG. 2, the source source 11 comprises one or more UV LEDs and an IR laser diode; the source is provided with a suitable interference filter 12. This source is particularly suitable for the analysis of objects comprising fluorescent tracers in the mass or on the surface.

The system for detecting the fluorescence signals 14 emitted by the object 10 when it is illuminated by the incident ray 13, comprises two devices:

 a collector of the fluorescence photons of the tracers contained in the object; and,

 a detector of the spectrometer type, which makes it possible to determine the wavelengths of the fluorescence signals emitted by the tracers.

The spectrometer may consist of a commercial rapid spectrometer or optimally designed from different elements as in the example shown in Figure 2:

- An inlet slot 15, this slot may be replaced by a calibrated hole or a row of small diameter fibers; a dispersive system for the diffraction grating type wavelengths 17, such a network being able to be replaced by a prism or a Perot-Fabry type device or interference filters selected for the fluorescence wavelengths of the tracers;

 one or more optics 16, 18 for collimation and concentration of the beams; and,

 at least one photon sensor 19, of high sensitivity.

The inlet may include one or more slots and / or one or more calibrated holes to simultaneously perform multiple analyzes of the same sample, object or particle, or more.

The optics may, for example, be a first objective 16 placed between the slot 15 and the network 17 and / or a second objective 18, placed between the network and the sensor 19. The second objective 18 and the sensors 19 may be part of a digital camera.

The sensor 19 can be chosen from:

 - photodiode arrays, these diodes may be avalanche or not; - CCD sensors;

 - EMCD sensors;

 - CMOS sensors.

The sensors can:

 - be linear or two-dimensional;

- be cooled or not;

 - integrate selective filters, for example Bayer matrix type, IR filter, L RGB filter;

- integrate one or more microlens networks. Linear CCD sensors are faster and can detect in 1ms integration times. The data transfer times are generally 2μ8. In the example illustrated, the sensor 19 is a Sony ICX445AL progressive monochrome CCD sensor. This sensor offers a better light sensitivity over the entire visible spectrum, than other known sensors, and especially on the middle to high wavelengths. In the illustrated example, the signal detected to identify the traced materials is a fluorescence intensity at specific wavelengths of the tracers. The choice of tracers and their concentration are dependent on the detection system, the fluorescence of the polymers and the fluorescence lifetime of the tracers and the size of the particles analyzed.

According to the invention, the choice of tracers and their concentration comprises the following steps:

 - analyze the fluorescence of the materials to be traced;

 determining an excitation and emission window where the fluorescence of the matrix materials is weak;

 - choose a plotter adapted to the existing reading material and materials on the market;

 calculate the tracer concentration to have a signal on noise allowing detection with a confidence interval of preferably 95%.

Particularly when the apparatus is used for sorting, the object may be a particle of material identifiable by the tracers it contains. The collection of the photons emitted by the particle, that is to say the fluorescence signals emitted under the effect of the incident ray is made, for example, using of an objective. This objective collects and concentrates the light signals emitted by one or more particles at the entrance of the apparatus. Alternatively or in addition, one or more optical fibers can be used to collect and transport the fluorescence signals emitted by a particle to the detector, in the case of a single fiber, or even the fluorescence signals emitted by several particles to the one or more detectors, in the case of a multi-strand fiber.

An apparatus according to the invention makes it possible to identify objects, particles or materials through the detection of a tracer signature for sorting or authenticating these objects, particles or materials. Such a device can be used or for a quality approach in the production of these objects, particles or materials. The apparatus detects one or more combinations of wavelengths and intensity forming a code corresponding to a signature. After analysis done with the device, such a code can in particular make it possible to know information related to this code, such as: the year of manufacture, the code of the manufacturer, the type of material, etc. Here, the type of tracer is given by the box colored in green giving the name of the tracer.

Tracer excitation is for example in the field of ultraviolet (stokes tracers) or infrared (anti-stokes tracer) and the detection of the polymer-tracer system is for example in the visible, in UV or infrared. This configuration is very favorable for light and dark colored plastics. The acquisition time is advantageously between 10 and 10000 ms. The excitation wavelengths of the tracers, will be included for the UV between 280 and 400 nm but may be extended to other wavelengths. For IR excitation, the lengths can range from 800 to 1500 nanometers. The detectors may be photomultiplier tubes, avalanche photodiodes or any device capable of detecting and / or amplifying light signals of low intensities, equipped with Perot-Fabry type devices, interference filters selected for the wavelengths of fluorescence tracers.

A system according to the invention, using an apparatus according to the invention, comprises a portable system for reading tracers, objects, in particular particles, to be identified composed of a material additive of fluorescent tracers.

Of course, the invention is not limited to the preferred embodiments which have just been described, but on the contrary the invention is defined by the following claims. It will be apparent to those skilled in the art that various modifications can be made to the embodiments described above, in the light of the teaching just disclosed.

Thus, what has previously been described with reference to the sorting of material particles is also applicable to authentication, that is to say, in particular to the fight against counterfeiting.

In addition, with identical detection system, in the visible and near infrared, it is possible to excite in the ultraviolet (Stokes effect) or around 900-1000 nm (anti-Stokes effect).

Claims

claims 1. Apparatus for analyzing (1) portable characterized in that it comprises means for illuminating (10,11) an object with an incident light ray and means (5, 15-19) for analyzing a signal emitted by the object under the effect of the incident ray. 2. Apparatus according to claim 1, characterized by comprising means for determining the presence and / or absence of tracers in the illuminated object. 3. Apparatus according to claim 2, characterized by comprising means for deriving a code based on the presence and / or absence of tracers in the illuminated object. 4. Apparatus according to one of claims 2 or 3, characterized in that comprising means for deriving conformity of the illuminated object to a reference and, preferably, alert means in case of non-compliance. 5. Apparatus according to one of claims 1 to 4, characterized in that the illumination means comprise one or more UV LEDs, and preferably a filter for filtering the light emitted by said LEDs. 6. Apparatus according to one of claims 1 to 5, characterized in that the analyzing means comprises a collector for fluorescence photons forming the fluorescence signal emitted by the tracers contained in the object; and a spectrometer type detector, which allows determine the wavelengths of the fluorescence signals emitted by said tracers. Apparatus according to claim 6, characterized in that the detector comprises:  an entrance slit (15);  a dispersive system for wavelengths, preferably of the diffraction grating type (17);  - one or more optics (16, 18) for collimation and beam concentrations; and,  a photon sensor (19) of high sensitivity. Apparatus according to claim 7, characterized in that the sensor is a progressive monochrome CCD sensor.