Dye-exchangeable zeolite marker

Abstract

A dye-exchanged zeolite marker, wherein the zeolite is characterized by a pore size comprised between 4 Å and 12 Å and the dye is an organic cationic molecule characterized by an amount of the dye comprised between 0.05% by weight and 1% by weight relative to the weight of the zeolite; an optically active composition comprising the dye-exchanged zeolite marker dispersed in a polymer matrix; and their use as detectable markers.

Description

Technical Field

[0001] The present invention relates to dye-exchanged zeolite markers, and an optically active composition comprising said markers dispersed in a polymer matrix. Background Art

[0002] Numerous patent publications, for example, European Patent Application Publication No. 1409997, European Patent Application Publication No. 1356478, International Publication No. 2011 / 045572, International Publication No. 2021 / 113377, or United States Patent Application Publication No. 2010 / 0003762, relate to the preparation of marking materials for a wide range of possible applications, for example, for anti-counterfeiting purposes, for inventory management or warranty purposes, for detecting the presence of a specific substance in a specific medium, or as packaging solutions. A known means for detecting a specific substance is represented by the use of colorimetric indicators, which rely on the optical properties of reactive dyes or inks under specific conditions. In particular, these dyes can exist in at least two different chemical states, wherein each form of the dye absorbs light in a specific wavelength range. When such a reactive dye present in the first form is exposed to a given substance, the reactive dye reacts with the substance via a reversible chemical reaction, thereby converting to the second form of the dye. Since the second form of the dye absorbs light of a different wavelength, the chemical reaction results in a visible and thereby detectable color change.

[0003] The incorporation of the aforementioned molecules into a desired substrate, which may also involve the use of zeolites, is typically achieved by impregnation methods disclosed in International Publication No. 2011 / 045572 or by post-treatment methods reported in U.S. Patent No. 11027241. Furthermore, Chinese Patent Application Publication No. 110903826 discloses the use of fluorescent molecules such as rhodamine incorporated into the surface of a metal-organic framework (MOF) type structure using diffusion impregnation techniques. Meanwhile, International Publication No. 2021 / 113377 describes antimicrobial zeolite nanoparticles that, in addition to metal species, may further contain optical tracers (e.g., fluorophores) that are non-covalently or covalently bonded to the surface of the zeolite but not bonded within the pores of the nanoparticles.

[0004] The main drawback of such methods is the limited stability of the final system, which tends to readily release dye molecules that decompose under extrusion in the case of thermoplastic matrices, or when exposed to heat treatment in the presence of water or other solvents.

[0005] Further possible methods reported in International Publication No. 2005 / 052069 are based on the use of pigments, the pigment compositions being realized by substitution reactions with one or more cationic dye groups in the presence of a suspension of zeolite pigments. However, one of the negative consequences of the use of both organic and inorganic pigments disclosed in International Publication No. 2005 / 052069 is related to the large amount of dye required relative to the amount of zeolite needed to obtain the desired color, and consequently, a high dye / zeolite ratio. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] European Patent Application Publication No. 1409997 [Patent Document 2] European Patent Application Publication No. 1356478 [Patent Document 3] International Publication No. 2011 / 045572 [Patent Document 4] International Publication No. 2021 / 113377 [Patent Document 5] U.S. Patent Application Publication No. 2010 / 0003762 [Patent Document 6] U.S. Patent No. 11027241 [Patent Document 7] Chinese Patent Application Publication No. 110903826 Specification [Patent Document 8] International Publication No. 2005 / 052069 [Non-patent literature]

[0007] [Non-Patent Document 1] T. Nedelcev et al. / Dyes and Pigments 76 (2008) 550e556 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] Therefore, there remains a need to develop novel chemical indicators, particularly markers, that provide simple, reliable, and cost-effective detection methods that exhibit improved stability compared to those known in the art, especially when threatened with heat or in contact with solvents. There also remains a need to develop novel optically active compositions incorporating such markers, which can be prepared and processed via known polymer processing techniques while maintaining the effectiveness and stability of the novel indicators. [Means for solving the problem]

[0009] The present invention overcomes the aforementioned drawbacks of the prior art by realizing a dye-exchange zeolite marker prepared by a cation exchange reaction between a zeolite cation and one of the dye organic molecules.

[0010] In the context of this disclosure, the term “dye-exchange zeolite marker” should be interpreted as meaning a marker or indicator that is zeolite-based, in particular, and can be obtained by a cation exchange reaction between a cationic dye and a zeolite, as is generally known in the art. The abbreviated form “marker” is used interchangeably with “dye-exchange zeolite marker.”

[0011] More specifically, with the aim of providing a marker species that can overcome the problems of the prior art relating to the low stability disclosed above, the inventors of the present invention have surprisingly found that when a cation exchange reaction occurs between the dye and the zeolite, the dye binds more efficiently to the zeolite, in particular to the pores of the zeolite, and as a result is not released or decomposed when in contact with a solvent or high-temperature conditions, i.e., it is more stable than those known in the art.

[0012] Accordingly, the present invention relates to a dye-exchange zeolite marker comprising a zeolite and a dye organic molecule, which can be obtained via a cation exchange reaction between at least one cation of the zeolite and at least one cation of the dye organic molecule.

[0013] Furthermore, it has become clear that by using a reduced amount of dye molecules relative to the zeolite, the detectable properties of the resulting marker can still be measured without altering the surface characteristics of the zeolite and its applicability to different applications. Accordingly, the present invention also relates to a dye-exchanged zeolite marker comprising a zeolite and a dye organic molecule, advantageously wherein the mass ratio between the dye and the zeolite is 0.05% to 1% by mass, preferably 0.1% to 0.5% by mass, relative to the mass of the zeolite. In other words, in contrast to those disclosed in the prior art, the marker of the present invention does not require a high dye / zeolite ratio to obtain the desired coloration.

[0014] As is clear from the experimental section of the present disclosure, measurement of zeolite pores may play an important role in the preparation of the dye-exchanged zeolite markers of the present invention, at least in terms of process yield. It has been found that zeolite dye-exchanged zeolites having a pore diameter comprised between 4 Å and 12 Å are particularly advantageous.

[0015] The present invention also relates to an optically active composition comprising the dye-exchanged zeolite marker disclosed herein and a polymer matrix, wherein the marker is preferably dispersed within said polymer matrix.

[0016] In addition, the present invention relates to the use of the dye-exchanged zeolite or composition disclosed herein as a detectable marker, and to a detectable article comprising or incorporating the dye-exchanged zeolite or composition according to the present invention, or coated (at least in part) with the dye-exchanged zeolite or composition according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] [Figure 1] It is a graph representing thermogravimetric analysis combined with mass spectrometry (TG-MS) for evaluating organic vapor generation during process simulation for samples C2 and S2. During the temperature ramp at 250°C, some organic generation was clearly identified for sample C2 due to the onset of decomposition, while for sample S2, no organic generation was present (always at zero level), confirming that no decomposition process was induced in this sample due to the stability of the dye-zeolite bond. MODE FOR CARRYING OUT THE INVENTION

[0018] As expected above, the inventors of the present invention found, as a result of intensive studies, that dye-exchanged zeolite markers obtained via a cation exchange reaction between zeolite and a dye are more stable than other zeolite-based markers already known in the art, in which the dye is merely adsorbed onto the zeolite.

[0019] Accordingly, the present invention relates to a dye-exchange zeolite marker comprising a zeolite and an organic cationic dye, which can be obtained via a cation exchange reaction between at least one cation of the zeolite and at least one cation of the organic cationic dye.

[0020] As is evident from the experimental section of this disclosure, the inventors have identified particularly advantageous zeolites with pore sizes ranging from 4 Å to 12 Å, which allow dyes to bind to the zeolite more efficiently and enable better process yields. Surface area and porosity analysis were performed using a Micromeritics BET instrument. Prior to analysis, samples were pre-prepared by degassing in a turbo vacuum at 180°C, which allowed for the removal of physically bound impurities from the analyte. Analysis was then continued using CO2 (at -20°C) for LTA or Ar (at -186°C) for other zeolites. Micropore surface area was calculated using the Dubinin Astakhov model, while pore size was calculated using the Saito Foley or NLDFT model.

[0021] Another important feature of the markers obtainable by the present invention is that effective detection is possible even with relatively low dye / zeolite mass ratios (see Samples S1-S4, Table 1). Surprisingly, even with a dye-to-zeolite mass ratio of 0.05% to 1% (preferably 0.1% to 0.5% - including the fractional values) relative to the zeolite mass, the marker enables effective detection without altering the surface characteristics of the zeolite.

[0022] Therefore, the present invention relates to a dye-exchange zeolite marker comprising a zeolite and a dye, - Zeolites are characterized by pore sizes ranging from 4 Å to 12 Å. - The dye is an organic cation molecule, - The amount of dye is contained in 0.05% to 1% by mass relative to the mass of the zeolite. Regarding dye-exchangeable zeolite markers.

[0023] Zeolites suitable for the purposes of the present invention are zeolites generally known in the art, provided that they have pore sizes ranging from 4 Å to 12 Å. Preferably, the zeolite is faujasite-type zeolite (FAU) or mordenite zeolite (MOR).

[0024] The dye is a colorimetric dye generally known in the art, preferably an organic cationic dye. Preferably, the dye is rhodamine or a derivative thereof, and more preferably, the dye is selected from the group consisting of rhodamine B, tetramethylrhodamine isothiocyanate-dextran, rhodamine 6G, rhodamine B isothiocyanate, rhodamine 19 percolate, and other rhodamine derivatives.

[0025] According to any embodiment of the present invention, the aforementioned zeolite contains X in a 0.5 to 50 μm, preferably 0.5 to 20 μm. 90 It is a powder form having an average particle size characterized by the value X 90 This indicates the spherical diameter within which 90% of the particles in the sample are contained, based on volume.

[0026] Since the dye efficiently binds to the inner portion of the zeolite, one of the further advantages of the marker relates to the possibility of utilizing the zeolite surface for further functionalization and activation.

[0027] In fact, in preferred embodiments of the present invention, the zeolite surface of the marker is modified with alkoxysilanes, such as (3-aminopropyl)trimethoxysilane, (3-aminopropyl)triethoxysilane, N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride, octadecyldimethyl(3-trimethoxysilylpropyl)ammonium chloride, tetradecyldimethyl(3-trimethoxysilylpropyl)ammonium chloride, n,n-didecyl-N-methyl-N-(3-trimethoxysilylpropyl)ammonium chloride, s-(trimethoxysilylpropyl)isothiouronium chloride, 3-(trihydroxysilyl)propyldimethyloctadecylammonium chloride, silsesquioxane 3-(dimethyloctadecylammonio)propyl, hydroxy-terminated chloride, and (3-glycidoxypropyl)trimethoxysilane. Modification is carried out using alkoxysilanes by hydrolysis and condensation. Preferably, the alkoxysilane derivative or alkoxysilane moiety is present in an amount of 1 to 40% by mass relative to the zeolite mass. The silane moiety can then be utilized for its inherent properties or as a linker for further reaction or polymerization steps.

[0028] Dye-exchange zeolite markers according to any of the embodiments disclosed herein can also be dispersed in a polymer matrix to obtain an optically active composition.

[0029] Accordingly, the present invention also relates to a composition comprising a dye-exchange zeolite marker according to any embodiment disclosed herein, and a polymer or polymer matrix. The polymer matrix should be characterized by not having excitation and emission features (peaks and / or more complex spectral features such that absorption and / or emission are generally increased) to a level where the excitation or emission of the marker may be disordered. In particular, since the excitation and emission peaks of the rhodamine or rhodamine derivative dyes are centered at 560 nm and 580 nm, respectively, a suitable polymer matrix is ​​characterized by not having excitation and emission features in the range included in 460 to 680 nm, considering the buffer spectral region specified by ±100 nm.

[0030] In preferred embodiments, the polymer matrix may be polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS) and their copolymers and functionalized polymers, acrylics, acrylic-styrene, vinyl and alkyl copolymers, urethane-acrylics, aliphatic-urethanes, urethanes, polyurethanes, epoxys, siloxanes and polysiloxanes, phenolic resins, poly[ethene-co-(vinyl alcohol)] (EVOH), poly(vinyl alcohol) (PVAL), poly(lactic acid-coglycolic acid) (PLGA), polyethylene glycol (PEG), poly(vinyl acetate) (PVAC), aqueous or water-dilutable latex, polylactic acid (PLA), aliphatic / aromatic copolymers The materials are selected from the group consisting of, preferably, polybutylene adipate terephthalate (PBAT) and poly(butylene sebacate-co-terephthalate) (PBSeT), poly(butylene succinate-co-butylene terephthalate) (PBST), 1,4-butanediol and aliphatic co-polyesters derived from carboxylic acids, preferably poly(butylene succinate) (PBS) and polybutylene succinate adipate (PBSA), polyhydroxyalkanoates (PHA), preferably polyhydroxybutyrate (PHB), poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV), polyhydroxybutyrate-hexanoate (PHBH), natural polymers, in particular polysaccharide polymers, such as chitosan, sodium alginate and starch or modified starch, and mixtures thereof. Preferred polymer blends include a blend of polylactic acid (PLA) and polyhydroxybutyrate / polyhydroxyvalerate (PHBV), or a blend of polyvinyl alcohol (PVOH) and hydroxypropylated starch ether (STARCH).

[0031] In the resulting active composition, the dye-exchanged zeolite marker is preferably present in an amount of 0.1 to 10% by mass relative to the mass of the polymer matrix.

[0032] In further embodiments, one or more additional components, such as fillers, are added to the composition, preferably in an amount of 0.1 to 20% by mass with respect to the polymer matrix. The additional components may be selected from the group consisting of, for example, hydrotalcite, zirconium phosphate, porphyrin, graphene and other two-dimensional crystals, zeolites, halloysite, graphene oxide, metal-organic frameworks (MOFs), organic beads, cellulose and antioxidant capsules, self-assembling proteins, ester-terminated polyamides, tertiary amide-terminated polyamides, polyether polyamides, polyalkylene oxy-terminated polyamides, and mixtures thereof.

[0033] As is evident from the following non-limiting examples, the dye-exchanged zeolites of the present invention, and polymer compositions containing them, have been shown to possess effective optical activity.

[0034] Accordingly, the present invention also relates to the use of the dye-exchanged zeolites or polymer compositions containing them as detectable markers.

[0035] As will be apparent to those skilled in the art, the dye-exchange zeolite or polymer composition of the present invention can be incorporated into or coated on items such as packaging, cloth, general plastics, etc., and the dye-exchange zeolite or polymer composition of the present invention can make the item itself or at least a part thereof detectable.

[0036] Accordingly, the present invention also relates to items or articles, preferably packaging, fabrics, garments, devices, such as medical devices, optical tags, marking components, and anti-counterfeiting elements, which include, incorporate, or are coated with at least a portion of a dye-exchanged zeolite or polymer composition according to any one of the embodiments disclosed herein.

[0037] In light of the foregoing, dye-exchanged zeolite according to any embodiment of the present invention can be processed into the form of a coating, film, lacquer, frame, three-dimensional element, pellet or sheet, or any other form suitable for the generally intended purpose.

[0038] The markers can be used as is to obtain the optically active composition, or they can be incorporated into the polymer matrix disclosed above.

[0039] Several methods can be used to prepare polymer / zeolite composites, such as in situ polymerization, polymer dissolution and mixing, extrusion, melt blending, or other molding processes (e.g., injection molding, transfer molding, compression molding, foaming, thermoforming, film blowing).

[0040] As will be apparent from the following experimental section, the present invention also relates to a method for preparing polymer compositions containing dye-exchange zeolite markers by any of the embodiments disclosed herein via in situ polymerization, polymer dissolution and mixing, or melt blending, and to compositions that can be obtained thereby. [Examples]

[0041] Experiment Section The present invention will be described in more detail below with reference to the following non-limiting examples. Modifications or variations of the embodiments illustrated herein that are obvious to those skilled in the art are included in the appended claims.

[0042] Preparation of rhodamine-exchanged zeolite markers (samples S1-S6 and corresponding example C1) Rhodamine B (RhB) or RhB-dextran (both from Sigma Aldrich) in amounts of 0.05 to 1.25 g was dissolved in 100 mL of distilled water. Then, 5 g of zeolite was added to the mixture, and the pH of the mixture was adjusted to 6 using HCl (1 M) solution. Protected from light, the mixture was stirred at RT for 24 hours using a laboratory magnetic stirrer. The resulting complex was then purified by filtration. Purification included thorough washing of the powder with distilled water until the collected filtrate was completely clear. The resulting rhodamine exchange complex was dried overnight in an oven at 80°C.

[0043] [Table 1]

[0044] Ion exchange reaction between 0.25g of RhB and LTA zeolite (C1) results in a very low rhodamine B content in the LTA zeolite (0.02% by mass), making this sample unsuitable for use as a marker.

[0045] Preparation of example C2 0.25 g of rhodamine B (RhB) was mechanically mixed with 5 g of zeolite to ensure efficient dispersion of various materials in powder form. The resulting mixture was dried overnight in an oven at 80°C.

[0046] Preparation of example C3 0.25 g of 9-(diethylamino)-5H-benzo[a]phenoxadin-5-one (alternative marker NR) was dissolved in 100 mL of dimethyl sulfoxide. Then, 5 g of zeolite was added to the mixture. Protected from light, the mixture was stirred at RT for 24 hours using a laboratory magnetic stirrer. The resulting complex was then purified by filtration. Purification included thorough washing of the powder with distilled water until the collected filtrate was completely clear. The resulting exchange complex was dried overnight in an oven at 80°C.

[0047] Preparation of example C4 0.25 g of fluorescein 5(6)-isothiocyanate (alternative marker FITC) was dissolved in 100 mL of distilled water. Then, 5 g of zeolite was added to the mixture. Protected from light, the mixture was stirred at RT for 24 hours using a laboratory magnetic stirrer. The resulting complex was then purified by filtration. Purification included thorough washing of the powder with distilled water until the collected filtrate was completely clear. The resulting exchange complex was dried overnight in an oven at 80°C.

[0048] Preparation of example C5 The (3-aminopropyl)triethoxysilane-rhodamine (APTES-RhB) molecule was prepared before its binding to the zeolite surface. Its synthesis followed the protocol described in T. Nedelcev et al. / Dyes and Pigments 76(2008)550e556. Briefly, rhodamine B (0.002 mol, 0.96 g) was dissolved in chloroform (30 ml). The solution was stirred and heated to the boiling point of chloroform (61.2 °C). Then, APTES (ABCR) (0.002 mol, 0.465 ml) was added dropwise to the rhodamine B solution under stirring. After 30 minutes, the reaction was stopped, and then chloroform was removed from the reaction mixture using a rotary evaporator. The residual material (silane-rhodamine, approximately 1.3 g) was dried in an oven at 60 °C.

[0049] Release tests for samples S1-S6 and corresponding examples C1-C4 In dye-exchange zeolite markers, the marker dispersion can be directly examined to verify that the dye efficiently binds to the zeolite and, as a result, is not released upon contact with the solvent or exposure to higher temperatures. 22.4 mg of selected samples (S1-S6) or corresponding examples (C1-C4) were dispersed in 20 g of solvent. The samples were vigorously stirred at room temperature (RT) and then allowed to stand for 24 hours. The supernatant was analyzed visually via simple naked-eye observation and compared to a reference colored sample (R1) obtained by dissolving 1.12 mg (2,34E-06 mol) of RhB powder in 20 g of solvent. The list of applicable solvents includes distilled water, acetone, dimethyl sulfoxide, tetrahydrofuran, chloroform, and dichloromethane (DCM). For all applicable solvents, complete clarity of the dispersion confirmed the absence of dye release, as reported in Table 2.

[0050] As a further test, the prepared sample dispersion was heated to 50°C for 10 minutes, vigorously stirred, and then allowed to stand for 24 hours. Again, the supernatant of the sample was analyzed visually through simple naked-eye observation and compared to a reference colored dye sample. The presence of a completely clear dispersion confirmed the absence of dye release and the lack of any spectrophotometric signals attributable to the dye, thus confirming the absence of release. The stability results observed for room-temperature samples were confirmed after the heat treatment, as reported in Table 2.

[0051] The dispersions prepared as reported above were further analyzed using a UV-Vis spectrophotometer. Calibration curves were defined for each solvent, and a detection limit (DL) of 1 ppm was determined. The effects of some parameters, such as solvent characteristics, temperature, and stirring time, were examined. The results are reported in Table 3. No absorption peaks were detected, and the detection limit was determined for each solvent, with a relative error calculated to be 15%.

[0052] [Table 2]

[0053] [Table 3]

[0054] To confirm the increased stability of the markers prepared according to the present invention, samples C2 and S2 were further subjected to a heating treatment simulating a polymer treatment characterized by a steep gradient to 250°C (50°C / min) and a 5-minute isotherm in a thermogravimetric mass spectrometer (TG-MS) instrument to identify trace amounts of organic matter derived from rhodamine B degradation. As reported in Graph 1, some organic matter was clearly identified when sample C2 was subjected to the above treatment, while the organic matter in sample S2 remained at a constant level of zero.

[0055] Contact angle test Contact angle measurement is a technique used to determine the wetting properties of a liquid droplet onto a solid surface. The contact angle is the angle formed between the tangent line in the droplet's three-phase contact line and the solid surface.

[0056] First, the target solid substrate was prepared and its wetting behavior was measured. In this case, the substrate was a zeolite powder pill. Next, small droplets of the substance under investigation were carefully placed on the solid surface using a syringe, micropipette, or other precise dispensing method.

[0057] Finally, images of the droplets on the solid surface were captured from a suitable angle using a high-resolution camera. Compared to standard protocols, imaging for zeolite pills must be extremely rapid, in less than 1 second. The obtained images were then processed using specific software to analyze the droplet shape and determine the contact angle.

[0058] When water is used as a liquid probe, a contact angle of <90° indicates that the sample is hydrophilic (polar surface, strong interaction with H2O), while a contact angle of >90° indicates that the sample is hydrophobic.

[0059] While typical zeolite surfaces are hydrophilic, zeolite surfaces can become hydrophobic when the powder surface is functionalized with organic molecules.

[0060] Contact angle analysis was performed on sample S2 and corresponding example C5. The relative results reported in Table 4 show that it is possible to have rhodamine in the pores of the zeolite only by the procedure of the present invention, whereas, according to procedures known in the art, rhodamine binds to the outer surface.

[0061] As a result, the zeolites disclosed herein, which contain rhodamine within their pores, are readily incorporated into further matrices / compositions, in contrast to hydrophobic zeolites such as C5, and in addition, the zeolites are characterized by the possibility of further interactions or functionalization on their surfaces.

[0062] [Table 4]

[0063] Preparation method for obtaining an optically active composition by dispersing a dye-exchanged zeolite marker in a polymer matrix. Several methods, such as in situ polymerization, polymer dissolution and mixing, or melt blending, can be used to prepare polymer / zeolite composites.

[0064] Preparation by in-situ polymerization is based on a first step involving the formulation of polymer precursors and the subsequent induction of dyes by using efficient techniques to obtain a fine dispersion. After obtaining a homogeneous dispersion, the liquid formulation is applied to a support, and the polymerization process is accelerated by initiator activation. Different activation regions can be applied according to the characteristics of the initiator and the chemical composition of the formulation. Typical methods are based on heat treatment or UV irradiation.

[0065] The solution mixing method comprises four steps: solubilization of the polymer matrix in a suitable solvent at room temperature or high temperature; dispersion of the zeolite in the solvent; mixing of the two solutions by mechanical stirring or tip / bath ultrasonic treatment; and finally, precipitation or casting of the mixture to obtain a film after evaporation of the solvent.

[0066] Melt blending is a commonly used technique for producing thermoplastic / zeolite composites. Melt blending utilizes high temperatures and high shear forces applied to industrial processes to disperse the zeolite. Depending on the desired final morphology / shape of the composite, the bulk material can be processed by various post-extrusion techniques such as film formation, injection molding, compression molding, and melt spinning.

[0067] The following are various examples, presented using various preparation methods according to the present invention:

[0068] [Table 5]

[0069] Sample AC 1. An active composition film was prepared by mixing 1.5 g of polyethylene glycol dimethacrylate (PEGDMA) with 0.07 g of ESACURE ONE (a bifunctional oligomer alpha-hydroxyketone) from IGM Resins as a free radical generating photoinitiator. After the photoinitiator was completely dissolved, 0.015 g of rhodamine-zeolite sample S2 was added to the mixture at room temperature, and mechanical mixing was performed for 30 minutes. The resulting mixture was spread on a glass substrate to a thickness of 50 microns using a doctor blade, and a UV lamp was used to expose it at 100 mW / cm². 2 At an illuminance of 1.5 J / cm², at a 365 nm focal point for 15 seconds. 2 The polymerization process was accelerated using the irradiation dose. The polymerization process was carried out in a glove box environment under an inert gas flux. A reference PEGDMA (UV-cured) film without the marker was also prepared using the same experimental protocol.

[0070] Sample AC 2. A film of the active composition was prepared by mixing 1.5 g of polyethylene glycol dimethacrylate with 0.07 g of azobisisobutyronitrile (AIBN) from Sigma Aldrich as a free radical generating thermal initiator. After the initiator was completely dissolved, 0.015 g of rhodamine-zeolite sample S2 was added to the mixture at room temperature and mechanical mixing was performed for 30 minutes. The resulting mixture was spread on a glass substrate to a thickness of 50 microns using a doctor blade, and the polymerization process was accelerated by heating the sample at 80°C for 30 minutes. The polymerization process was carried out under an inert gas flux in a glove box environment.

[0071] A reference PEGDMA (thermosetting) film without the marker was also prepared using the same experimental protocol.

[0072] Sample AC 3. A film of the active composition was prepared by mixing 0.9 grams of Epikote® 862 (bisphenol F resin) manufactured by Hexion with 0.15 grams of Epon 8111 (epoxy acrylate resin) and 0.38 grams of Epikote® 03161 (rubber-modified bisphenol A resin) manufactured by Hexion. The resulting mixture was vigorously stirred by mechanical mixing for 1 hour to obtain a homogeneous solution. Next, 0.08 grams of triaryl sulfonium hexafluoroantimonate was added as a cationic initiator and dissolved by mechanical stirring for 30 minutes. After the initiator was completely dissolved, 0.015 g of rhodamine-zeolite sample S2 was added to the mixture at room temperature and mechanical mixing was performed for a further 30 minutes. The resulting mixture was spread on a glass substrate to a thickness of 50 microns using a doctor blade and treated with UV light at 100 mW / cm². 2 The polymerization process was accelerated by applying an illuminance of λ=365nm for 120s.

[0073] A marker-free bisphenol F diglycidyl ether (DGEBF)-based reference film was also prepared using the same experimental protocol.

[0074] Sample AC 4. A film of the active composition was prepared by mixing 1.35 g of DOW's Sylgard® 184 A solution (polydimethylsiloxane, PDMS) with 0.15 g of DOW's 184 B solution (dimethyl, methylhydrogen siloxane copolymer) as a crosslinking agent for 10 minutes. Next, 0.015 g of rhodamine-zeolite sample S2 was added to the mixture at room temperature, and mechanical mixing was performed for a further 10 minutes. After obtaining a homogeneous dispersion, a degassing process was carried out under vacuum for 15 minutes. The resulting mixture was spread on a glass substrate to a thickness of 50 microns using a doctor blade, and the polymerization process was accelerated by heating the sample at 100°C for 30 minutes.

[0075] A reference PDMS film without the marker was also prepared using the same experimental protocol.

[0076] Sample AC 5. A film of the active composition was prepared by mixing 1.45 g of SunChemical's COMPOST LAM ADH (aliphatic polyisocyanate-based polyurethane, PU) with 0.05 g of alcohol dehydrogenase catalyst. Then, 0.015 g of rhodamine-zeolite sample S2 was added at room temperature, and the dispersion was stirred by mechanical mixing for 15 minutes. The resulting formulation was spread on a glass substrate to a thickness of 50 microns using a doctor blade, and the crosslinking reaction was promoted at room temperature.

[0077] A reference PU film without markers was also prepared using the same experimental protocol.

[0078] Sample AC 6. 1.5 g of LyondellBasell's low-density polyethylene (LDPE), grade LUPOLEN® 2420, was dissolved in 8.5 g of toluene at a boiling temperature of 110°C. After the polymer was dissolved, 0.015 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by bath sonication at room temperature for 30 minutes, followed by vigorous mechanical mixing for 1 hour.

[0079] The resulting formulation was spread onto a Teflon® foil to a thickness of 50 microns using a doctor blade, and solvent evaporation was accelerated at 50°C. A composite film containing 1% by mass of the marker in the polymer matrix was obtained. A reference LDPE film without the marker was also prepared using the same experimental protocol.

[0080] Sample AC 7. 1.5 g of Versalis (ENI) atactic polystyrene (PS), grade EDISTIR® N1910, was dissolved in 8.5 g of toluene at a boiling temperature of 110°C. After the polymer was dissolved, 0.015 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by bath sonication at room temperature for 30 minutes, followed by vigorous stirring by mechanical mixing for 1 hour. The resulting formulation was spread on a Teflon® foil to a thickness of 50 microns using a doctor blade, and solvent evaporation was accelerated at 50°C. A composite film containing 1 mass% of the marker in the polymer matrix was obtained. A reference PS film without the marker was also prepared by applying the same experimental protocol.

[0081] Sample AC 8. 1.0 g of GoodFellow's polylactic acid (PLA) (MFR=8) was dissolved in 9.0 g of chloroform at a boiling temperature of 61°C. After the polymer was dissolved, 0.01 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by bath sonication at room temperature for 30 minutes, followed by vigorous stirring by mechanical mixing for 1 hour. The resulting formulation was spread on a Teflon® foil to a thickness of 50 microns using a doctor blade, and solvent evaporation was accelerated at 40°C. A composite film containing 1% by mass of the marker in the polymer matrix was obtained. A reference PLA film without the marker was also prepared by applying the same experimental protocol.

[0082] Sample AC 9. 1.0 g of GoodFellow's polyhydroxybutyrate (PHB) was dissolved in 20.0 g of chloroform at a boiling temperature of 61°C. After the polymer was dissolved, 0.03 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by bath sonication at room temperature for 30 minutes, followed by vigorous stirring by mechanical mixing for 1 hour. The resulting formulation was spread on a Teflon® foil to a thickness of 50 microns using a doctor blade, and solvent evaporation was accelerated at 40°C. A composite film containing 3% by mass of the marker in the polymer matrix was obtained. A reference PHB film without the marker was also prepared by applying the same experimental protocol.

[0083] Sample AC 10. 1.0 g of GoodFellow's 2% polyhydroxybutyrate / polyhydroxyvalerate (PHBV) was dissolved in 20.0 g of chloroform at a boiling temperature of 61°C. After the polymer was dissolved, 0.03 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by bath sonication at room temperature for 30 minutes, followed by vigorous stirring by mechanical mixing for 1 hour. The resulting formulation was spread on a Teflon® foil to a thickness of 50 microns using a doctor blade, and solvent evaporation was accelerated at 40°C. A composite film containing 3% by mass of the marker in the polymer matrix was obtained. A reference PHBV film without the marker was also prepared by applying the same experimental protocol.

[0084] Sample AC 11. 1.0 g of polyvinyl alcohol (PVOH): grade Exceval® AQ-4104 from Kuraray was dissolved in 9.0 g of distilled water at a boiling temperature of 100°C. After the polymer was dissolved, 0.01 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by bath sonication at room temperature for 30 minutes, followed by vigorous stirring by mechanical mixing for 1 hour. The resulting formulation was spread on a glass substrate to a thickness of 50 microns using a doctor blade, and water evaporation was accelerated at 50°C. A composite film containing 1% by mass of the marker in the polymer matrix was obtained. A reference PVOH film without the marker was also prepared by applying the same experimental protocol.

[0085] Sample AC 12. 1.0 g of SOLAM's hydroxypropylated starch ether (STARCH): grade SOLCOAT P85 was dissolved in 9.0 g of distilled water at a boiling temperature of 100°C. After the polymer was dissolved, 0.01 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by bath sonication at room temperature for 30 minutes, followed by vigorous stirring by mechanical mixing for 1 hour. The resulting formulation was spread on a glass substrate to a thickness of 50 microns using a doctor blade, and water evaporation was accelerated at 40°C. A composite film containing 1% by mass of the marker in the polymer matrix was obtained. A reference STARCH film without the marker was also prepared by applying the same experimental protocol.

[0086] Example AC 13 (Blend 1). 0.7 g of GoodFellow's polylactic acid (PLA) (MFR=8) and 0.3 g of GoodFellow's 2% polyhydroxybutyrate / polyhydroxyvalerate (PHBV) were dissolved in 18.0 g of chloroform at a boiling temperature of 61°C. After the polymer was dissolved, 0.05 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature, and the dispersion was mixed by bath sonication at room temperature for 30 minutes, followed by vigorous mechanical mixing for 1 hour. After casting the solution, a composite film containing 3% by mass of the marker in the polymer matrix was obtained. A reference PLA / PHBV film without the marker was also prepared by applying the same experimental protocol.

[0087] Example AC 14 (Blend 2). 0.7 g of polyvinyl alcohol (PVOH): grade Exceval® AQ-4104 from Kuraray and 0.3 g of hydroxypropylated starch ether (STARCH): grade SOLCOAT P85 from SOLAM were dissolved in 9.0 g of distilled water at 90°C under vigorous stirring. After the polymer was completely dissolved, 0.01 g of rhodamine-zeolite sample S2 was added to the polymer solution at room temperature (RT). The dispersion was mixed by bath sonication at RT for 30 minutes and then vigorously stirred at RT for 1 hour by mechanical mixing. The resulting formulation was spread on a glass substrate to a thickness of 50 microns using a doctor blade, and water evaporation was accelerated at 50°C. A reference PVOH / starch film without markers was also prepared using the same experimental protocol.

[0088] Example AC 15. 49 g of ≤400 micron low-density polyethylene powder purchased from Alfa Aesar was compounded for 5 minutes via a melt blend with 1 g of rhodamine-zeolite (sample S2) using a Lab Two Roll Open Mixing Mill (Battaggion). The roll processing conditions were as follows: front roller temperature = 130°C; back roller temperature = 80°C; roll speed = 33 rpm. The resulting compound material was compression molded using a laboratory press (Gibitre Instruments) at P=230 bar and T=175°C for 5 minutes to obtain a sheet (thickness ≈ 200 μm) containing 2 mass% of markers. A reference polyethylene sheet without markers was also prepared according to the same experimental protocol.

[0089] Example AC 16. 49 g of polylactic acid (Grade NatureWorks 2003D) was compounded for 5 minutes via a melt blend with 1 g of rhodamine-zeolite (Sample S2) using a Lab Two Roll Open Mixing Mill (Battaggion). The roll processing conditions were as follows: front roller temperature = 155°C; back roller temperature = 125°C; roll speed = 33 rpm. The resulting compound material was compression molded using a laboratory press (Gibitre Instruments) at P=230 bar and T=190°C for 5 minutes to obtain a sheet (thickness ≈ 200 μm) containing 2 mass% of the marker. A reference polylactic acid sheet without the marker was also prepared according to the same experimental protocol.

[0090] Example AC 17. 48.5 g of GoodFellow's 2% polyhydroxybutyrate / polyhydroxyvalerate (PHBV) was compounded for 5 minutes via a melt blend with 1.5 g of rhodamine-zeolite (Sample S2) using a Lab Two Roll Open Mixing Mill (Battaggion). The roll processing conditions were as follows: front roller temperature = 170°C; back roller temperature = 145°C; roll speed = 33 rpm. The resulting compound material was compression molded using a laboratory press (Gibitre Instruments) at P=230 bar and T=190°C for 5 minutes to obtain a sheet (thickness ≈ 200 μm) containing 3 mass% of the marker. A reference PHBV sheet without the marker was also prepared according to the same experimental protocol.

[0091] Example AC 18 98 g of acrylonitrile butadiene styrene ABS (Grade Terluran® GP-22, manufactured by INEOS STYROLUTION) was compounded for 5 minutes via a melt blend with 2 g of rhodamine zeolite (Sample S5) using a Lab Bench Top Two-Roll Mill (LabTech Engineering). The roll processing conditions were as follows: front roller temperature = 175°C; back roller temperature = 170°C; roll speed = 10 rpm. The resulting compound material containing 2 mass% of marker S5 was formed into a sheet (thickness 500 μm). A reference ABS sheet without the marker was prepared according to the same preparation protocol.

[0092] [Table 6A]

[0093] [Table 6B]

[0094] Determination of marker and matrix optical properties Equipment description. A Horiba FluoroMax® Plus spectrofluorometer was used for the measurement. A continuous light source P was focused on the inlet slot of the excitation monochromator. oA 150W ozone-free xenon arc lamp was used. The instrument was based on two Czerny-Turner monochromators, whose reflection gratings dispersed the incident light. Optical spectra were obtained by rotating the gratings and recording the intensity values ​​at each wavelength. The inlet and outlet ports of each monochromator contained continuously adjustable slits to control the spectral resolution, and the intensity of the fluorescence signal was recorded by a photomultiplier tube. Polymer products in the form of marker-added films or plates were tested using a solid sample holder fitted with an adjustable goniometer. A sample setting with a 60° angle between the incident and specularly reflected beams was used to prevent the excitation beam from entering through the emission slit, thereby avoiding stray light interference. FluorEssence® analytical measurement software was used for data acquisition and processing.

[0095] Description of the sample characterization protocol To detect the presence of the dye within the polymer matrix, the marker excitation and emission peaks in the polymer matrix were compared with those of a reference sample (polymer matrix without the marker) and a pure marker excitation and emission peak. Considering the fluorescence of the dye, sample performance was studied as the ratio between the fluorescence intensity I of the active composition and the fluorescence intensity I0 of the pure polymer matrix without the dye, after subtracting the excitation at 540 nm. According to the applied protocol, a value greater than 2 for the I / I0 ratio indicated that the presence of the marker was detectable. Table 5 below reports the recorded values ​​for all test samples.

[0096] [Table 7]

Claims

1. A dye-exchange zeolite marker containing zeolite and a dye, a) The zeolite is in the form of a powder having an average particle size characterized by an X90 value contained in 0.5 to 50 μm and a pore size contained in 4 Å to 12 Å. b) The dye is an organic cation molecule selected from the group consisting of rhodamine B, tetramethylrhodamine isothiocyanate-dextran, rhodamine 6G, rhodamine B isothiocyanate, and rhodamine 19 percolate. c) The amount of dye is contained in 0.05% to 1% by mass relative to the mass of the zeolite. Dye-exchangeable zeolite marker.

2. The dye-exchange zeolite marker according to claim 1, wherein the zeolite is faujasite-type zeolite (FAU) or mordenite zeolite (MOR).

3. The dye-exchange zeolite marker according to claim 1, wherein the zeolite has a surface that is modified or functionalized with an alkoxysilane derivative.

4. A dye-exchange zeolite marker according to claim 1, obtained via a cation exchange reaction between at least one cation of the zeolite and at least one cation of the dye.

5. A composition comprising a dye-exchange zeolite marker according to claim 1 dispersed in a polymer matrix, wherein the polymer matrix is ​​selected from polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS) and their copolymers and functionalized polymers, acrylic, acrylic-styrene, acrylic-vinyl and alkyl copolymers, urethane-acrylic, urethane, polyurethane, epoxy, siloxane and polysiloxane, phenolic resin, poly[ethene-co-(vinyl alcohol)] (EVOH), poly(vinyl alcohol) (PVAL), poly(lactic acid-coglycolic acid) (PLGA), polyethylene glycol (PEG), poly(vinyl acetate) (PVAC), aqueous or water-dilutable latex, polylactic acid (PLA), aliphatic or aromatic co-polyesters, and natural polymers.

6. The composition according to claim 5, wherein the dye-exchange zeolite marker is present in an amount of 0.1 to 10% by mass relative to the polymer matrix.

7. The composition according to any one of claims 5, wherein the polymer matrix is ​​treated in the form of a coating, film, lacquer, frame, three-dimensional element, pellet, or sheet.

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