EP3152357A1

EP3152357A1 - Method for marking a textile thread with a fluorescent element, textile thread produced by the marking method, and use of said textile thread for weaving an item of clothing

Info

Publication number: EP3152357A1
Application number: EP15732836.0A
Authority: EP
Inventors: Aurélien AUGER; Sonia De Sousa nobre; Daniel Getto
Original assignee: Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
Current assignee: Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
Priority date: 2014-06-04
Filing date: 2015-06-02
Publication date: 2017-04-12
Also published as: FR3021979A1; WO2015185850A1; US20170152627A1

Abstract

Method for marking a textile thread with a fluorescent element, textile thread produced by the marking method, and use of said textile thread for weaving an item of clothing. The invention relates to a method for marking a textile thread with a fluorescent element, comprising the following successive steps: placing a textile thread and at least one fluorescent element in a reaction chamber; introducing a fluid into the reaction chamber; and increasing the temperature and the pressure in the reaction chamber to a temperature Ts and a pressure Ps so as to transform the fluid into a supercritical fluid and to mark the textile thread with the florescent element. The fluorescent element is selected from organolanthanide complexes.

Description

Method for marking a textile yarn by a fluorescent element, textile yarn obtained by the marking process and use of said textile yarn for weaving a garment

Technical field of the invention

The invention relates to a method of marking a textile yarn by a fluorescent element and also relates to a textile yarn obtained by said method.

State of the art

An increasing number of manufactured products are being misrepresented. Counterfeit goods are difficult to distinguish from original products, in particular because of the quality of reproduction and / or the fact that they can be distributed through the same distribution networks as the original products. The textile sector is one of the most affected by these reproductions.

In addition to economic losses (destruction of jobs, loss of profits to businesses), reproductions are often made under unsuitable hygienic conditions and by a low-skilled workforce, which can make these products dangerous to health. not only for employees but also for consumers.

It is essential to put in place actions to protect these products, often copied almost identically.

To facilitate the detection of copies, some products may be marked with an authenticating element. It can be a secure optical marking, suitable for textile labels.

Object of the invention

The object of the invention is to overcome the drawbacks of the prior art and, in particular, to propose a method of marking a simple garment that is easy to implement, the marking having to be difficult both to copy. and, at the same time, easily identifiable.

This object is approached by the appended claims.

Brief description of the drawings

Other advantages and features will emerge more clearly from the following description of particular embodiments of the invention given by way of non-limiting example and represented in the accompanying drawings, in which:

FIG. 1 represents a photograph of a textile yarn, marked according to the process of the invention, and of an unlabeled textile yarn,

FIG. 2 represents a photograph of the two textile threads of FIG. 1, illuminated under an ultraviolet lamp,

FIG. 3 represents an emission spectrum of a textile yarn marked according to the method of the invention.

DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION The method of marking a textile thread with a fluorescent element comprises the following successive steps: placing a textile yarn and at least one fluorescent element in a reaction chamber,

introducing a fluid into the reaction chamber,

to increase the temperature and the pressure in the reaction chamber to a temperature Ts, greater than the critical temperature of the fluid Te, and up to a pressure Ps, greater than the critical pressure of the fluid Pc, so as to transform the fluid in supercritical fluid and to mark the textile yarn by the fluorescent element. In the textile industry, supercritical fluids, such as carbon dioxide, can be used to color / impregnate textile materials such as polyester-type synthetic fibers with pigments (EP 1 126 072 and Kikic et al., Current Opinion in Solid State and Materials Science 2003, 7, 399-405). The process significantly reduces the amount of waste water / polluted compared to conventional dyeing processes.

The process nevertheless requires the use of a small quantity of water in the reaction chamber, for example in the form of a relative humidity of between 10% and 100%, to improve the reactivity and / or the accessibility of the fibers.

However, such a visual only marking is quite easy to counterfeit.

The marking method used is a method of marking a textile yarn by a fluorescent element. A distinctive fluorescent element is affixed to the textile yarn. The marking is a fluorescent marking.

The marking is advantageously invisible to the naked eye and therefore difficult to identify by a person who does not know the specificity of the marking. By marking process is meant a process which makes it possible to mark the material without altering its properties and, in particular, without coloring it. The marking is advantageously homogeneous. The marking may be surface or volume. The volume marking advantageously makes it possible to have a mark both at the surface and in the depth. Even if the surface molecules lose their properties or are eliminated because of successive washings and / or prolonged exposure to the sun, the molecules at depth can act as a reservoir. The service life of the material is thus increased.

After marking, the fluorescent element is bonded to the textile yarn. The fluorescent element can not be dissociated from the textile yarn by a simple washing for example. The holding of the marking is also resistant to ethanol, acetone and water. The marking can not be removed by simply rubbing a cloth on the resulting textile yarn.

By textile yarn is meant an agglutination of textile fibers to form a long set. Textile yarns are intended to be woven to form fabrics, for the manufacture of clothing for example.

Textile yarn is a synthetic textile yarn based on polymer, or in cotton or leather.

The synthetic textile yarn comprises from 1% to 88.5% by mass of a polymeric material.

Preferably, the polymeric material is polyester: the textile yarn comprises from 1% to 88.5% by weight of polyester.

The polyester may be chosen from poly (glycolic acid) (PGA), poly (lactic acid) (PLA), polycaprolactone (PCL), polyhydroxyalkanoate (PHA), polyethylene adipate (PEA) and polybutylene succinate (PBS). ), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN).

According to a preferred embodiment, the polyester is polyethylene terephthalate (PET). The remainder of the weight percentage may be impurities, fixing agents, dyes, etc.

For example, for a textile yarn comprising 88.5% by weight of polymeric material, the remainder of the percentage may correspond to 2.3% impurities, 0.7% pretreatment agents (to make, for example, bleaching), 6.5% dyes and fixers dyes, and 2% finalizing agents (fire treatment, water repellent treatment, ...).

By fluorescent element is meant an element having the property of being able to absorb light and to re-emit it at a longer wavelength.

The fluorescent element is formed of at least one fluorescent molecule.

Advantageously, the fluorescent element is composed of a multitude of fluorescent molecules of the same nature or of different natures.

Preferably, the fluorescent molecules are of the same nature.

The amount of fluorescent molecules is chosen to be sufficient to be able to impregnate the textile yarn and give it detectable fluorescent properties.

The fluorescent element is preferably chosen from phthalocyanines and organo-lanthanide complexes.

According to a preferred embodiment, the fluorescent element is an organo-lanthanide complex. Advantageously, the use of an organo-lanthanide complex makes it possible not to color the material to be marked. The marking is invisible to the naked eye.

The organo-lanthanide complexes, also called lanthanide complexes, are formed from trivalent lanthanide ions, denoted Ln ³⁺ , and organic molecules, called ligands. The ligands are, for example, β-diketonates or carboxylic acids. Advantageously, the emission of the lanthanide complexes is characterized by very fine bands positioned at well-defined wavelengths: each lanthanide complex has its own optical fingerprint.

It is therefore possible to specifically mark a textile yarn with a particular wavelength.

The organo-lanthanide complexes formed from the ions Ce ³⁺ and Gd ³⁺ emit in the spectral regions of the UV-near and make it possible to mark the textile thread by a fluorescent element in the UV-near; complexes formed from Tm ³⁺ ions in blue; complexes formed from Tb ³⁺ and Er ³⁺ ions in green; complexes formed from Dy ³⁺ ions in the yolk; complexes formed from Sm ³⁺ ions in orange; complexes formed from Er ³⁺ , Eu ³⁺ in red, and complexes formed from Nd ³⁺ , Er ³⁺ , Tm ³⁺ , and Yb ³⁺ ions in the near infrared.

It is possible to associate several lanthanide complexes to obtain more complex optical signatures.

Advantageously, the lanthanide complexes are dispersed homogeneously in the textile yarn and are invisible to the naked eye. The marking does not change the appearance of the product. The marking is said to be stealthy.

Subject to appropriate light excitation, their fluorescence is detectable by any suitable device. It may be, for example, a portable spectrometer. The presence of lanthanide complexes can, in particular, be detected with low cost commercially available detectors. Preferably, the organo-lanthanide complex is a europium complex.

According to another embodiment, the fluorescent element is a phthalocyanine. The use of phthalocyanine makes it possible to obtain both a fluorescent marking and a coloration of the thread. The yarn may advantageously be used to produce a particular pattern, visible to the naked eye, during weaving of the garment. Phthalocyanine may be a phthalocyanine or a phthalocyanine derivative. In particular, it may be 1, 4,8,1 1, 15,18,22,25-Octabutoxy-29H, 31H-phthalocyanine, 5,9, 14,18,23,27, 32,36-Octabutoxy-2,3-naphthalocyanine, 5,9,14,18,23,27,32,36-octabutoxy-2,3-naphthalocyanine copper (II), 1, 4.8 , 1 1, 15,18,22, 25-octabutoxy-291-1,31 H-phthalocyanine nickel (II).

The fluorescent element is advantageously introduced in the form of a powder into the reaction chamber.

The fluorescent element may be mixed with the fluid, or placed next to it in the reaction chamber.

The substrate may be immersed in the fluid at the beginning of the process, or may be placed next to it.

The fluid is transformed into supercritical fluid when it is heated to a temperature Ts greater than its critical temperature T _c and when it is compressed at a pressure Ps greater than its critical pressure P _c .

To obtain the supercritical fluid from the fluid, the chamber is heated to reach a pressure Ps greater than the pressure P _c and a temperature Ts greater than the pressure T _c .

The supercritical fluid generally has a density close to that of the liquid and a viscosity close to that of the gas. The supercritical fluid allows a better diffusion than the corresponding liquid phase. It also reduces surface tension. Preferably, the fluid is introduced into the chamber in liquid form. Alternatively, it could be introduced in gaseous form. Otherwise, the fluid could be introduced into the reaction chamber in the supercritical state.

The supercritical fluid is advantageously inert vis-à-vis the textile yarn.

Preferably, the fluid introduced into the reaction chamber is carbon dioxide. Even more preferentially, it is liquid carbon dioxide.

It is a solvent called "green", that is to say non-polluting for the environment. The process, involving carbon dioxide, does not generate polluting discharges aqueous or organic, harmful to the environment.

Preferentially, the pressure Ps and the temperature Ts are maintained for a period of at least 15 minutes. This duration makes it possible to produce a homogeneous and continuous coating, at least on the surface of the textile yarn.

Advantageously, the duration is between 15 minutes and 10 hours. The choice of the duration makes it possible to fix the quantity of fluorescent molecules penetrating and fixing in the textile thread. Preferably, the pressure Ps is between 100bars and 400bars, and still more preferably between 300bars and 350bars.

Preferentially, the temperature Ts is between 50 ° C. and 200 ° C., and even more preferably the temperature Ts is between 110 ° C. and 150 ° C.

These ranges of pressure and temperature make it possible to position themselves beyond the critical point of the fluid and to transform the carbon dioxide into supercritical carbon dioxide. The pressure Pc and the temperature Tc of the critical point are respectively 31 ° C and 74bars for carbon dioxide. The supercritical fluid is then absorbed by the textile yarn: the supercritical fluid enters the fibers of the textile yarn. The fluorescent element is entrained in the textile yarn by the supercritical fluid.

The supercritical fluid traps the fluorescent element in the textile yarn: the textile yarn is impregnated, marked by the fluorescent element.

Once the textile yarn is impregnated, the pressure and / or the temperature are lowered below the critical point of fluid so as to eliminate the fluid absorbed by the textile yarn. The pressure and the temperature are then decreased until reaching a room temperature and an ambient pressure.

A textile thread marked with a fluorescent element is obtained. Fluorescent molecules are trapped in the textile yarn under ambient conditions of temperature and pressure (i.e. around 20-25 ° C and 1 bar).

According to a particular embodiment, a solvent is placed in the reaction chamber. Advantageously, the solvent is placed in the reaction chamber before introducing the supercritical fluid.

The solvent makes it easier to solubilize the fluorescent element. A larger amount of fluorescent element can be used, which advantageously makes it possible to limit the reaction time required to obtain the marking of the textile yarn.

Preferably, the solvent is an organic solvent. The fluorescent element advantageously has a better solubility in an organic solvent.

The solvent is advantageously chosen from dichloromethane, ethanol, acetone, tetrahydrofuran and trichloromethane. The process does not require or few solvents, depending on the embodiments. There are therefore fewer fluorescent elements lost in the circuits solvents. It is not necessary to treat the effluents. This point is particularly advantageous because one of the main problems of textile industries is the treatment of residues (Directive 2008/1 / EC). In one embodiment, the method does not require the use of water. The fluid is free of water and the solvent is free of water.

The process will be described by means of the following examples given by way of nonlimiting illustration.

For each of the following examples, a textile yarn is introduced into a tubular reaction chamber equipped with a manometer and a thermometer. The marker, i.e. the fluorescent element, is also introduced into the reaction chamber.

The mass ratio textile yarn / fluorescent element is between 1% by mass and 20% by mass. Preferably, the mass ratio textile yarn / fluorescent element is 10% ± 1%.

At this stage of the process, an organic solvent can also be introduced. It can be introduced using a graduated syringe.

The volume of solvent is between 0.5 mL and 1 mL.

The reactor is then charged with liquid CO2 until a first pressure of 80 bar ± 20 bar, i.e., from 60 bar to 100 bar.

The reactor is then heated with a heating element to a temperature Ts of between 50 ° C and 200 ° C. The temperature is chosen according to the desired pressure Ps, the pressure Ps being between 100 and 400 bars.

The CO2 is then in its supercritical state, that is to say at a temperature above the temperature of the critical point Te of 31 ° C and at a pressure higher than the pressure of the critical point Pc of 74 bars, which allows the transfer of the fluorescent molecule to the surface and / or in the volume of the textile yarn.

The conditions are kept constant for a time t of between 15 minutes and 10 hours.

After stopping the heating, the temperature of the reaction chamber will gradually decrease to room temperature, then the residual pressure is broken, the pressure stabilizes at ambient pressure, i.e. around 1 bar.

The table below lists various tests performed.

The phthalocyanine of Example No. 3 is 1, 4,8,1,1,15,18,22,25-Octabutoxy-291-1,31H-phthalocyanine.

The labeling of the polymeric substrates by the fluorescent element was observed with the naked eye, under an ultraviolet (UV) lamp and by confocal optical microscopy. FIG. 2 shows a textile thread marked with a europium complex and an unlabeled textile thread under the light of day, and FIG. 3 represents the same textile threads under ultraviolet light (UV at 365 nm).

Under ultraviolet light, the marked wire is red. The fluorescence in the red is clearly visible. The control wire is not fluorescent.

The emission spectrum of the europium complex-labeled yarn was measured with an Ocean Optics portable spectrometer - figure 3. The method makes it possible to obtain a textile thread marked with at least one fluorescent element.

The fluorescent element is, advantageously, a europium complex.

The textile yarn can be marked with several fluorescent elements.

The textile yarn comprises between 1% and 88.5% by weight of polyester. The textile yarn is used to weave at least a portion of a garment.

The garment comprises at least one textile yarn obtained according to the method described above.

Advantageously, the marking is incorporated in the garment: it is integrated into the product and is therefore resistant to tearing and / or rubbing, unlike the markings made on garment labels.

This type of marking is also resistant to washing and rinsing. Fluorescent marking will allow authentication throughout the product life cycle.

One or more markings can be included in the same garment, thus reinforcing the protection of the products.

This type of marking, by these specificities, is highly secure and particularly difficult to copy. The detection of marking is easy and it is thus easy to spot imitations.

Claims

claims

A method of marking a textile yarn by a fluorescent element comprising the following successive steps:

placing a textile yarn and at least one fluorescent element in a reaction chamber,

introducing a fluid into the reaction chamber,

to increase the temperature and the pressure in the reaction chamber to a temperature Ts, greater than the critical temperature of the fluid Te, and up to a pressure Ps, greater than the critical pressure of the fluid Pc, so as to transform the fluid in supercritical fluid and to mark the textile yarn by the fluorescent element,

characterized in that the fluorescent element is selected from organo-lanthanide complexes.

2. Method according to claim 1, characterized in that the supercritical fluid introduced into the reaction chamber is liquid carbon dioxide.

3. Method according to one of claims 1 and 2, characterized in that the textile yarn comprises from 1% to 88.5% by weight of polyester.

4. Method according to claim 3, characterized in that the polyester is polyethylene terephthalate.

5. Method according to any one of claims 1 to 4, characterized in that the fluorescent element is a europium complex.

6. Method according to any one of claims 1 to 5, characterized in that the mass ratio textile yarn / fluorescent element is between 1% and 20% by mass.

7. Method according to any one of claims 1 to 6, characterized in that the pressure Ps and the temperature Ts are maintained for a period of at least 15 minutes, and preferably for a period of between 15 minutes and 10 hours. .

8. Method according to any one of claims 1 to 7, characterized in that the pressure Ps is between 100bar and 400bar, and preferably between 300bar and 350bar.

9. Process according to any one of claims 1 to 8, characterized in that the temperature Ts is between 50 ° C and 200 ° C, and preferably between 1 10 ° C and 150 ° C.

10. Process according to any one of claims 1 to 9, characterized in that a solvent is placed in the reaction chamber before introducing the fluid.

11. Method according to any one of claims 1 to 10, characterized in that a plurality of fluorescent elements are arranged in the reaction chamber.

12. Textile yarn, obtained according to the process according to any one of claims 1 to 1 1, said textile yarn being labeled with at least one fluorescent element selected from organo-lanthanide complexes.

13. Textile yarn according to claim 12, characterized in that the yarn comprises between 1% and 88.5% by weight of polyester.

14. Textile yarn according to one of claims 12 and 13, characterized in that the fluorescent element is a europium complex.

15. Textile yarn according to any one of claims 12 to 14, characterized in that the textile yarn is marked with several fluorescent elements.

16. Use of a textile yarn according to any one of claims 12 to 15 for weaving at least part of a garment.

Garment comprising at least one textile yarn according to any one of claims 12 to 15.