ANTI-UV COATING

Abstract

A filtering film including compounds absorbing UV-light in a range from 300 nm to 380 nm and a binder, wherein the weighted mean absorbance A.sub.380 is greater than 2, and packaging having a substrate that is partially or totally covered with the filtering film or formed from the filtering film. Also, methods of protection of consumer goods against UV-light, in which the consumer goods are enclosed by the filtering film.

Claims

1. A filtering film comprising compounds absorbing UV-light in a range from 300 nm to 380 nm and a binder, wherein the weighted mean absorbance A.sub.380 of the filtering film is greater than 2, with A.sub.380 defined by the following relation: $A_{380}=\frac{{}_{300}^{380}W\left(\right)A\left(\right)d}{{}_{300}^{380}W\left(\right)d}$ where A() represents the absorbance of the filtering film at a given wavelength, and W() represents a weighting function equal to the product of the solar spectrum irradiance E.sub.S() and a sensitivity function S() defined as a gaussian function with the peak centered at 300 nm and a standard deviation of 24 nm; and wherein the compounds absorbing UV-light comprise semi-conductive nanoparticles having a formula ##STR00003## wherein: M is selected from the group consisting of Zn, Cd, Hg, Cu, Ag, Al, Ga, In, Si, Ge, Sn, Pb and a mixture thereof; E is selected from the group consisting of S, Se, Te, N, P, As, Sb, and a mixture thereof; x and y are independently a decimal number from 0 to 5; and x and y are not simultaneously equal to 0; wherein the compounds absorbing UV-light further comprise organic anti-UV compounds selected from the group consisting of benzotriazoles, triazines, piperidines, benzophenones, catechol, their derivatives, and mixtures thereof; and wherein the organic compounds absorbing UV-light in the filtering film are present in an amount that is in a range from 2 wt % to 15 wt %, based on the weight of the filtering film, for a 10 m-thick film.

2. The filtering film according to claim 1, wherein the weighted mean absorbance A.sub.380 is greater than 2.5.

3. The filtering film according to claim 1, wherein the weighted mean absorbance A.sub.340 of the filtering film is greater than 2, with A.sub.340 defined by the following relation: $A_{340}=\frac{{}_{300}^{340}W\left(\right)A\left(\right)d}{{}_{300}^{340}W\left(\right)d}.$

4-5. (canceled)

6. The filtering film according to claim 1, wherein compounds absorbing UV-light comprise semi-conductive nanoparticles having a local maximum absorbance of highest wavelength in a range from 320 nm to 360 nm.

7-8. (canceled)

9. The filtering film according to claim 1, wherein organic compounds absorbing UV-light are selected from the group consisting of benzotriazoles, triazines, piperidines, benzophenones, catechol, their derivatives, and mixtures thereof.

10-11. (canceled)

12. The filtering film according to claim 1, wherein the filtering film is transparent and uncolored.

13-14. (canceled)

15. The filtering film according to claim 1, wherein the filtering film has a thickness that is in a range from 2 m to 100 m.

16. A packaging comprising a substrate partially or totally covered with a filtering film according to claim 1 or formed from the filtering film.

17. The packaging according to claim 16, wherein the packaging is selected from the group of consisting of glass containers, glass bottles, plastic containers and plastic bottles.

18. A method of protection of a consumer good against UV-light in a range from 300 nm to 340 nm comprising enclosing the consumer good in a filtering film according to claim 1.

19. The method of protection according to claim 18, wherein the consumer good is selected from food, cosmetic formulations or fragrance.

20. The method of protection according to claim 19, wherein the consumer good is contained in a packaging covered with the filtering film.

21. The filtering film according to claim 1, wherein compounds absorbing UV-light comprise II-VI type semi-conductive nanoparticles and comprise a core based on cadmium, sulfur and selenium and are selected in the group consisting of: CdSe/CdS, CdSe/CdS/ZnS, CdSe/CdS/ZnSe, CdSe/CdS/ZnSe.sub.yS.sub.(1-y), CdSe/ZnSe/ZnS, CdSe/ZnSe.sub.xS.sub.(1-x) ZnS, CdSe.sub.xS.sub.(1-x)/ZnS, CdSe.sub.xS.sub.(1-x)/ZnSe, CdSe.sub.xS.sub.(1-x)/ZnSe.sub.yS.sub.(1-y), CdSe.sub.xTe.sub.(1-x)/ZnS, CdSe.sub.xTe.sub.(1-x)/ZnSe, CdSe/Cd.sub.yZn.sub.(1-y) S, CdSe/Cd.sub.yZn.sub.(1-y) S/ZnS, CdSe/Cd.sub.yZn.sub.(1-y) S/ZnSe, CdSe/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z) CdSe/Cd.sub.yZn.sub.(1-y) Se, CdSe/Cd.sub.yZn.sub.(1-y) Se/ZnS, CdSe/Cd.sub.yZn.sub.(1-y) Se/ZnSe, CdSe/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z), CdSe.sub.xS.sub.(1-x)/CdS, CdSe.sub.xS.sub.(1-x)/CdS/ZnS, CdSe.sub.xS.sub.(1-x)/CdS/ZnSe, CdSe.sub.xS.sub.(1-x)/CdS/ZnSe.sub.yS.sub.(1-y), CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnS, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z), CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnS, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z), wherein x, y and z are rational numbers between 0 and 1, 0 and 1 being excluded; or comprise a core based on zinc, sulfur and selenium and are selected in the group consisting of: ZnSe/ZnS, ZnSe/ZnSe.sub.yS.sub.(1-y), ZnTe/ZnSe.sub.yS.sub.(1-y) ZnSe.sub.xS.sub.(1-x) ZnS, ZnSe.sub.xS.sub.(1-x)/ZnSe, ZnSe.sub.xS.sub.(1-x)/ZnSe.sub.yS.sub.(1-y), ZnSe.sub.xTe.sub.(1-x)/ZnS, ZnSe.sub.xTe.sub.(1-x)/ZnSe, ZnSe.sub.xTe.sub.(1-x)/ZnSe.sub.xS.sub.(1-x), ZnSe/Cd.sub.yZn.sub.(1-y) S, ZnSe/Cd.sub.yZn.sub.(1-y) S/ZnS, ZnSe/Cd.sub.yZn.sub.(1-y) S/ZnSe, ZnSe/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z) ZnSe/Cd.sub.yZn.sub.(1-y) Se, ZnSe/Cd.sub.yZn.sub.(1-y) Se/ZnS, ZnSe/Cd.sub.yZn.sub.(1-y) Se/ZnSe, ZnSe/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z), ZnSe.sub.xS.sub.(1-x) ZnS, ZnSe.sub.xS.sub.(1-x)/ZnS/ZnSe, ZnSe.sub.xS.sub.(1-x) ZnS/ZnSe.sub.yS.sub.(1-y), ZnSe.sub.xS.sub.(1-x) Cd.sub.yZn.sub.(1-y) S, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnS, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z), ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnS, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z), wherein x is a rational number between 0 and 0.6, 0 being excluded and 0.6 being included, and y and z are rational numbers between 0 and 1, 0 and 1 being excluded; or comprise a core based on zinc, cadmium, sulfur and selenium selenium and are selected in the group consisting of: Cd.sub.wZn.sub.(1-w) Se/CdS, Cd.sub.wZn.sub.(1-w) Se/CdS/ZnS, Cd.sub.wZn.sub.(1-w) Se/ZnSe/ZnS, Cd.sub.wZn.sub.(1-w) Se/CdS/ZnSe, Cd.sub.wZn.sub.(1-w) Se/CdS/ZnSe.sub.yS.sub.(1-y), Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/ZnS, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/ZnSe, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/ZnSe.sub.yS.sub.(1-y), Cd.sub.wZn.sub.(1-w) Se.sub.xTe.sub.(1-x)/ZnS, Cd.sub.wZn.sub.(1-w) Se.sub.xTe.sub.(1-x)/ZnSe, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) S, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) S/ZnS, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) S/ZnSe, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z) Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) Se, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) Se/ZnS, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) Se/ZnSe, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z), Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/CdS, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/CdS/ZnS, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/CdS/ZnSe, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x) CdS/ZnSe.sub.yS.sub.(1-y), Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnS, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z), Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnS, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z), where w, x, y and z are rational numbers between 0 and 1, 0 and 1 being excluded.

22. A filtering film comprising compounds absorbing UV-light in a range from 300 nm to 380 nm and a binder, wherein the weighted mean absorbance A.sub.380 of the filtering film is greater than 2, with A.sub.380 defined by the following relation: $A_{380}=\frac{{}_{300}^{380}W\left(\right)A\left(\right)d}{{}_{300}^{380}W\left(\right)d}.$ where A() represents the absorbance of the filtering film at a given wavelength, and W() represents a weighting function equal to the product of the solar spectrum irradiance E.sub.S() and a sensitivity function S() defined as a gaussian function with the peak centered at 300 nm and a standard deviation of 24 nm; and wherein compounds absorbing UV-light comprise semi-conductive nanoparticles having a formula ##STR00004## wherein: M is selected from the group consisting of Zn, Cd, Hg, Cu, Ag, Al, Ga, In, Si, Ge, Sn, Pb and a mixture thereof; E is selected from the group consisting of S, Se, Te, N, P, As, Sb, and a mixture thereof; x and y are independently a decimal number from 0 to 5; and x and y are not simultaneously equal to 0; wherein: the filtering film is transparent and uncolored.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0040] FIG. 1 illustrates various nanoparticles with homostructure (A) or heterostructures: spherical core/shell (B), spherical core/shell/shell (C), dot in plate (D), nanoplate core/shell (E) and nanoplate core/crown (F).

[0041] FIG. 2 shows absorbance curves as a function of wavelength of 7 different odorant molecules often used in fragrances (noted S1 to S7) devoid of UV-stabilizers. The curve of the sensitivity function S() is shown in dotted line.

[0042] FIG. 3 shows absorbance curves as a function of wavelength A() for a commercial coating (Comparative example in dotted line) and Ex. 1 (in double line).

[0043] FIG. 4 shows absorption curves as a function of wavelength A() for a commercial coating (Comparative example in dotted line) and Ex. 4 (in continuous line).

[0044] FIG. 5 shows the UV-visible spectrum of a fragrance (absorbance A) as a function of wavelength (2 in nm) in different conditions. A0 represent a fragrance before SUNTEST. D0-6 h represents the spectrum of the fragrance devoid of any UV protection after 6 hours of SUNTEST. Dref_add-6 h represents a fragrance comprising an additivemainly avobenzoneafter 6 hours of SUNTEST. Dref_coat-6 h represents a fragrance protected by the reference coating of comparative example after 6 hours of SUNTEST. DEx3-6 h represents a fragrance protected by the filtering film of example 3 after 6 hours of SUNTEST.

[0045] FIG. 6 shows the relative decrease (%) of absorbance at 500 nm of a reference fragrance during time (t in hours) under SUNTEST conditions. DO represents a fragrance devoid of UV protection: a strong and quick degradation is observed. Dref_add represents a fragrance comprising an additivemainly avobenzonesetting the standard protection of the industry. Dref_coat represents a fragrance protected by the reference coating of comparative example. DEx3 represents a fragrance protected by the filtering film of example 3.

DETAILED DESCRIPTION

[0046] In the present invention, the following terms have the following meanings:

[0047] Absorbance is the decimal logarithm of ratio I.sub.0/I, where I.sub.0 is the intensity of light incident on a sample and I is the intensity of light transmitted through said sample. Absorbance is measured for wavelengths in UV and visible range from 300 nm to 780 nm.

[0048] Encapsulated refers to a state in which a materialan encapsulating materialcoats, surrounds, embeds, contains, comprises, wraps, packs, or encloses a plurality of particles, which may be nanoparticles or composite particles.

[0049] Loading charge refers to the mass ratio between the mass of particles comprised in a formulation and the mass of said formulation. For the sake of clarity, 10 g of particles mixed with 90 g of a matrix defines a loading charge of 10%.

[0050] Nanometric size refers to a size of matter in which quantum effects appear due to confinement. For semi-conductive nanoparticles, nanometric size has to be defined with the average Bohr radius of an electron/hole pair. Confinement is effective for size in at least one dimension of nanoplates below 10 nm, preferably below 5 nm. Confinement is effective for section of nanorods below 100 nm.sup.2, preferably below 50 nm.sup.2. Confinement is effective for diameter of nanospheres below 20 nm, preferably below 15 nm, more preferably below 10 nm.

[0051] Nanoparticle refers to a particle having a size in at least one of its dimensions below 100 nm. For a nanosphere, diameter should be below 100 nm. For a nanoplate, thickness should be below 100 nm. For a nanorod, diameter should be below 100 nm.

[0052] Semi-conductive nanoparticles refers to particles made of a material having an electronic structure corresponding to semi-conductive materials known in electronic industry but having a nanometric size. Due to their specific electronic structure, semi-conductive materials behave as high-pass absorbing materials. Indeed, light having a wavelength more energetic than band gap may be absorbed by the semi-conductive material, yielding an electron/hole pair, an exciton, which later recombine in the material and dissipate heat, or emit light, or both. On the contrary, light having a wavelength less energetic than band gap cannot be absorbed: semi-conductive material is transparent for these wavelengths. In macroscopic semi-conductive materials, visible light is generally absorbed while near/mid infra-red light is not absorbed. When semi-conductive particles have a nanometric size, confinementi.e., shape and nanometric sizegoverns electronic structure following the rules of quantum mechanics and light absorption may be limited to UV range or UV and high energy visible light.

[0053] Transparent: refers to a film with two properties. First, light scattering by the film should be low, typically below 1% as measured with standard haze measurement according to ASTM D1003-00, preferably below 0.8%, even preferably below 0.5%. Second, the shape of an object seen throughout the film should be unaltered, in the sense that a consumer can recognize an object when looking through the film. In this disclosure, transparency is not related to the absorbance of visible light: a film may be transparent and coloured. Optionally, the film is uncoloured when the absorbance of the film is less than 0.05 for a range of wavelength from 420 nm to 780 nm, preferably from 400 nm to 780 nm, more preferably for the whole visible range: from 380 nm to 780 nm. With such low absorbance, there is no attenuation effect visible by eye, nor change in colour perception: the film is transparent and uncoloured.

[0054] UV-Light: refers to electromagnetic radiations having a wavelength comprised between 280 nm and 380 nm. In this disclosure UV-C light having wavelength below 280 nm is not considered.

[0055] Visible light refers to electromagnetic radiations having a wavelength comprised between 380 nm and 780 nm.

[0056] wt % refers to the weight percentage of a component in a blend or a formulation, based on the weight of the solid blend-after drying or cure, as the case may be.

Weighted Mean Absorbance:

[0057] This disclosure relates to a filtering film comprising compounds absorbing UV-light in a range from 300 nm to 380 nm and a binder. This filtering film presents a weighted mean absorbance A.sub.380 greater than 2, with A.sub.380 defined by the following relation:

[00003]$A_{380}=\frac{{}_{300}^{380}W\left(\right)A\left(\right)d}{{}_{300}^{380}W\left(\right)d}$

where A() represents the absorbance of the filtering film at a given wavelength , and W() represents a weighting function equal to the product of the solar spectrum irradiance E.sub.S()which can be found in ASTM G177-03 (2012) standardand a sensitivity function S().

[0058] Various analysis run by the applicant have shown that odorant molecules often used in fragrancesdevoid of UV stabilizerspresent similar absorption spectra in UV-light, as shown in FIG. 2for diluted fragrances. Indeed, notwithstanding some variations in amplitude, absorbance may be fitted with a gaussian function having its peak centered at 300 nm and a standard deviation of 24 nmthe right side of a gaussian function actually. Therefore, throughout the following disclosure, the sensitivity function S() is defined as a gaussian function with the peak centered at 300 nm and a standard deviation of 24 nm. The values considered in the present disclosure are presented in the following table:

TABLE-US-00001 TABLE I solar spectrum Wavelength irradiance E.sub.S () Sensibility Weighting fonction (nm) (mW/m.sup.2 .Math. nm) S() W() 300 0.081 1.000 0.081 305 1.91 0.979 1.869 310 11 0.917 10.088 315 30 0.823 24.694 320 54 0.707 38.205 325 79.2 0.582 46.123 330 101 0.459 46.366 335 128 0.347 44.360 340 151 0.251 37.834 345 170 0.173 29.491 350 188 0.115 21.624 355 210 0.073 15.338 360 233 0.044 10.349 365 253 0.026 6.544 370 279 0.014 4.025 375 306 0.008 2.358 380 336 0.004 1.324

[0059] The value of weighted mean absorbance A.sub.380 greater than 2which means that 99% of photons in the range of 300 nm to 380 nm are absorbed by the filmhas proven beneficial in ageing test presented below in examples. Indeed, a commercial filtering solution with A.sub.380 equal to 1.8 was not satisfactory, whereas filtering film disclosed in example 4 with A.sub.380 equal to 2.4 was satisfactory.

[0060] In an embodiment, the filtering film is transparent, preferably transparent and uncoloured.

[0061] In an embodiment, the thickness of the filtering film is in a range from 2 m to 100 m, preferably from 3 m to 50 m, more preferably from 5 m to 25 m. Throughout the disclosure, filtering films have a preferred thickness of 10 m. It is however clear that the thickness of the filtering film is not critical for absorption performance. Indeed, a low concentration of compounds absorbing UV-light in a filtering film may be compensated by a greater thickness of the film, as taught basically by Beer-Lambert lawnotwithstanding nonlinear effects encountered with highly concentration of compounds absorbing UV-light. Therefore, the concentration of compounds absorbing UV-light is defined in association with a 10 m thick film; in order to define the absolute amount of compounds absorbing UV-light in the filtering film. Another film thickness-either thicker but more diluted; or thinner but more concentratedmay be equivalent.

[0062] In an embodiment, the weighted mean absorbance A.sub.380 is greater than 2.5, preferably greater than 3. Greater values for A.sub.380 are possible, for instance greater than 4, or 5.

[0063] Even if the weighting function W() gives a more important role to the absorption in the range of wavelength from 300 nm to 340 nm, the contribution in higher wavelength is not negligible. In an embodiment, the filtering film presents a weighted mean absorbance A.sub.340 greater than 2, with A.sub.340 defined by the following relation:

[00004]$A_{340}=\frac{{}_{300}^{340}W\left(\right)A\left(\right)d}{{}_{300}^{340}W\left(\right)d}$

where the functions have the same definitions as hereabove for A.sub.380. Indeed, A.sub.340 is more focused on the range of wavelength associated with aldhehyde functions of odorous compounds and provides a better characterization of filtering effect. A weighted mean absorbance A.sub.340 greater than 2 means that 99% of photons in the range of 300 nm to 340 nm are absorbed by the film. In an embodiment, the weighted mean absorbance A.sub.340 is greater than 2.5, preferably greater than 3. Greater values for A.sub.340 are possible, for instance greater than 4 or 5.

Compounds Absorbing UV-Light:

[0064] In the disclosure, the filtering film comprises compounds absorbing UV-light, which may be of various types.

Semi-Conductive Nanoparticles

[0065] In an embodiment, compounds absorbing UV-light are semi-conductive nanoparticles. Semi-conductive nanoparticles bring especially interesting light absorbing properties to filtering films comprising them. In particular, with proper selection of composition and structure of semi-conductive nanoparticles, filtering films having a sharp transition between range of absorbed light (of high energy) and range of transmitted light (low energy) may be designed.

[0066] Due to their electronic structure, semi-conductive nanoparticles behave as high pass filters: absorbance is high for wavelength of high energy, i.e., short wavelengths. On the contrary, absorbance for wavelength of low energy, i.e., long wavelengths, is low. The transition between both domains of high and low absorbance may be defined by the wavelength .sub.max defined as follow: .sub.max corresponds to the local maximum absorbance of highest wavelength in the range from 300 to 500 nm.

[0067] In other words, light of wavelength less than the wavelength .sub.max will not be transmitted whereas light of wavelength greater than the wavelength .sub.max will be transmitted. Advantageously, in the present disclosure, .sub.max is in the range from 320 nm to 360 nm: absorption in the range from 300 nm to 340 nm is thus very efficient to avoid aldehyde degradation, while absorption in visible light is negligible in order to avoid any undesired coloration of the filtering film. Preferably, .sub.max is in the range from 320 nm to 350 nm, more preferably in the range from 320 nm to 340 nm. The wavelength .sub.max of the semi-conductive nanoparticles can be adjusted depending on the composition, shape, dimensions and direct environment of the semi-conductive nanoparticles.

[0068] Semi-conductive nanoparticles with higher .sub.max may be desirable to impart some filtering properties to the filtering film in UV-light, or even visible light. For instance, the semi-conductive nanoparticles may have a .sub.max in the range from 350 nm to 400 nm, preferably from 350 nm to 380 nm. The property of semi-conductive nanoparticles to behaves as high pass filters is especially interesting, as all light of wavelength inferior to the wavelength .sub.max is blocked.

[0069] Especially suitable semi-conductive nanoparticles have a formula

##STR00002##

wherein: [0070] M is selected from the group consisting of Zn, Cd, Hg, Cu, Ag, Al, Ga, In, Si, Ge, Sn, Pb or a mixture thereof; [0071] E is selected from the group consisting of O, S, Se, Te, N, P, As, Sb, or a mixture thereof; [0072] x and y are independently a decimal number from 0 to 5; and [0073] x and y are not simultaneously equal to 0.

[0074] In a specific embodiment, semi-conductive nanoparticles comprise a material selected from the group consisting of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, HgS, HgSe, HgTe, HgO, GeS, GeSe, GeTe, SnS, SnSe, SnTe, PbS, PbSe, PbTe, GeS.sub.2, GeSe.sub.2, SnS.sub.2, SnSe.sub.2, CuInS.sub.2, CuInSe.sub.2, CuInZnS, CuInZnSe, AgInS.sub.2, AgInSe.sub.2, CuS, Cu.sub.2S, Ag.sub.2S, Ag.sub.2Se, Ag.sub.2Te, FeS, FeS.sub.2, InP, Cd.sub.3P.sub.2, Zn.sub.3P.sub.2, CdO, ZnO, Al.sub.2O.sub.3, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, InSb, InAsP, or a mixture thereof

[0075] In this disclosure, semi-conductive nanoparticles may have different shapes, provided that they present a nanometric size leading to confinement of exciton created in the nanoparticle. Semi-conductive nanoparticles may be nanospheres, nanoplates or nanorods.

[0076] Semi-conductive nanoparticles may have nanometric sizes in three dimensions, allowing quantum confinement in all three spatial dimensions. Such semi-conductive nanoparticles are for instance nanocubes or nanospheres.

[0077] Semi-conductive nanoparticles may have a nanometric sizes in two dimensions, the third dimension being larger: quantum confinement is in two spatial dimensions. Such semi-conductive nanoparticles are for instance nanorods, nanowires or nanorings.

[0078] Semi-conductive nanoparticles may have a nanometric size in one dimension, the other dimensions being larger: quantum confinement is in one spatial dimension only. Such semi-conductive nanoparticles are for instance nanoplates, nanosheets, nanoribbons or nanodisks. Nanoplates are especially interesting in this disclosure because absorption cross sectioni.e., efficiency to capture a photon of incident light on the nanoparticleis ten times higher than a nanosphere having the same composition and structure. This higher cross section improves significantly absorption.

[0079] The exact shape of semi-conductive nanoparticles defines confinement properties; then electronic and optical properties depending on composition of semi-conductive nanoparticle, in particular the band gap, then .sub.max of the final filtering film. It has been also observed that nanoparticles with a nanometric size in one dimension, especially nanoplates, present a sharper transition between both domains of high and low absorbance as compared to nanoparticles with other shapes. Indeed, width of transition zone is enlarged if nanometric size of nanoparticles fluctuates around a mean value. When nanometric size is controlled in only one dimension, i.e. for nanoplates, by a strict number of atomic layers, thickness fluctuations are almost null and transition between absorbing and non-absorbing state is very sharp. This leads to particularly efficient filtering films.

[0080] In an embodiment, semi-conductive nanoparticles are homostructures. By homostructure, it is meant that the semi-conductive nanoparticle is homogenous and has the same local composition in all its volume. A homogeneous spherical semi-conductive nanoparticle (1) is illustrated in FIG. 1A.

[0081] In an alternative embodiment, semi-conductive nanoparticles are heterostructures. By heterostructure, it is meant that the semi-conductive nanoparticles is comprised of several sub-volumes, each sub-volume having a different composition from neighbouring sub-volumes. In a particular embodiment, all sub-volumes have a composition defined by formula (I) disclosed above, with different parameters, i.e., elemental composition and stoichiometry.

[0082] Examples of heterostructure are core/shell nanoparticles, the core (11) having any shape disclosed above. A shell (12) is a layer covering totally or partially the core. A particular example of core/shell heterostructure is a multi-layered structure comprising a core (11) and several successive shells (12, 13). For convenience, these multi-layered heterostructures are named core/shell hereafter. Core (11) and shell (12,13) may have the same shape-sphere in sphere for exampleor notsphere in plate for instance. A core/shell spherical nanoparticle is illustrated in FIG. 1B. A core/shell/shell spherical nanoparticle is illustrated in FIG. 1C. A sphere in plate nanoparticle is illustrated in FIG. 1Dalso named a dot in plate. A core/shell nanoplate is illustrated in FIG. 1E.

[0083] Another example of heterostructure are core/crown nanoparticles, the core having any shape disclosed above. A crown is a band of material disposed on the periphery of the core. This heterostructure is particularly useful with cores being nanoplates and crown disposed on the edges of the nanoplate. A core/crown nanoplate is illustrated in FIG. 1F.

[0084] These heterostructure may have a gradient of composition from the core to the outside of the shell so that there is no precise boundary between core and shell but properties in centre of the core are different from properties on the outer boundary of shell.

[0085] In a configuration, semi-conductive nanoparticles are II-VI type and comprise a core based on cadmium, sulfur and selenium and are selected from: [0086] CdSe/CdS, CdSe/CdS/ZnS, CdSe/CdS/ZnSe, CdSe/CdS/ZnSe.sub.yS.sub.(1-y), CdSe/ZnSe/ZnS, CdSe/ZnSe.sub.xS.sub.(1-x)/ZnS, [0087] CdSexS.sub.(1-x)/ZnS, CdSexS.sub.(1-x)/ZnSe, CdSexS.sub.(1-x)/ZnSe.sub.yS.sub.(1-y), CdSe.sub.xTe.sub.(1-x)/ZnS, CdSe.sub.xTe.sub.(1-x)/ZnS, [0088] CdSe/Cd.sub.yZn.sub.(1-y) S, CdSe/Cd.sub.yZn.sub.(1-y) S/ZnS, CdSe/Cd.sub.yZn.sub.(1-y) S/ZnSe, CdSe/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z) [0089] CdSe/Cd.sub.yZn.sub.(1-y) Se, CdSe/Cd.sub.yZn.sub.(1-y) Se/ZnS, CdSe/Cd.sub.yZn.sub.(1-y) Se/ZnSe, CdSe/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z), [0090] CdSe.sub.xS.sub.(1-x)/CdS, CdSe.sub.xS.sub.(1-x)/CdS/ZnS, CdSe.sub.xS.sub.(1-x)/CdS/ZnSe, CdSe.sub.xS.sub.(1-x)/CdS/ZnSe.sub.yS.sub.(1-y), [0091] CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnS, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z), [0092] CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnS, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe, CdSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z),
where x, y and z are rational numbers between 0 (excluded) and 1 (excluded).

[0093] In a configuration, semi-conductive nanoparticles are II-VI type and comprise a core based on zinc, sulfur and selenium and are selected from: [0094] ZnSe/ZnS, ZnSe/ZnSe.sub.yS.sub.(1-y), ZnTe/ZnSe.sub.yS.sub.(1-y) [0095] ZnSe.sub.xS.sub.(1-x)/ZnS, ZnSe.sub.xS.sub.(1-x)/ZnSe, ZnSe.sub.xS.sub.(1-x)/ZnSe.sub.yS.sub.(1-y), ZnSe.sub.xTe.sub.(1-x)/ZnS, ZnSe.sub.xTe.sub.(1-x)/ZnSe, ZnSe.sub.xTe.sub.(1-x)/ZnSe.sub.xS.sub.(1-x), [0096] ZnSe/Cd.sub.yZn.sub.(1-y) S, ZnSe/Cd.sub.yZn.sub.(1-y) S/ZnS, ZnSe/Cd.sub.yZn.sub.(1-y) S/ZnSe, ZnSe/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z) [0097] ZnSe/Cd.sub.yZn.sub.(1-y) Se, ZnSe/Cd.sub.yZn.sub.(1-y) Se/ZnS, ZnSe/Cd.sub.yZn.sub.(1-y) Se/ZnSe, ZnSe/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z), [0098] ZnSe.sub.xS.sub.(1-x)/ZnS, ZnSe.sub.xS.sub.(1-x)/ZnS/ZnSe, ZnSe.sub.xS.sub.(1-x)/ZnS/ZnSe.sub.yS.sub.(1-y), [0099] ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnS, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z), [0100] ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnS, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe, ZnSe.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z),
where x, y and z are rational numbers between 0 (excluded) and 1 (excluded). In this configuration, x is preferably a rational number between 0 (excluded) and 0.6.

[0101] In a configuration, semi-conductive nanoparticles are II-VI type and comprise a core based on zinc, cadmium, sulfur and selenium and are selected from: [0102] Cd.sub.wZn.sub.(1-w) Se/CdS, Cd.sub.wZn.sub.(1-w) Se/CdS/ZnS, Cd.sub.wZn.sub.(1-w) Se/ZnSe/ZnS, Cd.sub.wZn.sub.(1-w) Se/CdS/ZnSe, Cd.sub.wZn.sub.(1-w) Se/CdS/ZnSe.sub.yS.sub.(1-y), [0103] Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/ZnS, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/ZnSe, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/ZnSe.sub.yS.sub.(1-y), Cd.sub.wZn.sub.(1-w) Se.sub.xTe.sub.(1-x)/ZnS, Cd.sub.wZn.sub.(1-w) Se.sub.xTe.sub.(1-x)/ZnSe, [0104] Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) S, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) S/ZnS, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) S/ZnSe, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z) [0105] Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) Se, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) Se/ZnS, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) Se/ZnSe, Cd.sub.wZn.sub.(1-w) Se/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z), [0106] Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/CdS, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/CdS/ZnS, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/CdS/ZnSe, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/CdS/ZnSe.sub.yS.sub.(1-y), [0107] Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnS, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) S/ZnSe.sub.zS.sub.(1-z), [0108] Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnS, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe, Cd.sub.wZn.sub.(1-w) Se.sub.xS.sub.(1-x)/Cd.sub.yZn.sub.(1-y) Se/ZnSe.sub.zS.sub.(1-z),
where w, x, y and z are rational numbers between 0 (excluded) and 1 (excluded).

[0109] Most preferred II-VI nanoparticles are CdSe/CdS/ZnS, CdSe.sub.xS.sub.(1-x)/CdS/ZnS, CdSe/ZnSe/ZnS, CdSe/ZnSe.sub.xS.sub.(1-x)/ZnS, CdSe.sub.xS.sub.(1-x)/ZnSe/ZnS, Cd.sub.xZn.sub.(1-x) Se/ZnSe/ZnS, ZnSe.sub.xS.sub.(1-x)/ZnS, ZnSe.sub.xS.sub.(1-x)/ZnSe, ZnSe.sub.xS.sub.(1-x)/ZnSe.sub.yS.sub.(1-y).

[0110] Other particularly suitable nanoparticles are III-V type semi-conductive nanoparticles and are selected from InP/ZnS, InP/ZnSe, InP/ZnSe.sub.xS.sub.(1-x), InP/CdS/ZnS, InP/ZnSe/ZnS, InP/ZnSe.sub.xS.sub.(1-x)/ZnS, InP/GaP, Cu.sub.xIn.sub.yZn.sub.(1-x-y)S/ZnS, In.sub.xAs.sub.(1-x) P/ZnSe.sub.xS.sub.(1-x), where x and y are rational numbers between 0 (excluded) and 1 (excluded).

[0111] Other particularly suitable nanoparticles are I-III-VI.sub.2 type semi-conductive nanoparticles and are selected from AgInS.sub.2, AgInSe.sub.2, Cu.sub.xIn.sub.(1-x) S.sub.2, Cu.sub.xIn.sub.(1-x)Se.sub.2, especially CuInS.sub.2 and CuInSe.sub.2, where x is a rational numbers between 0 (excluded) and 1 (excluded).

[0112] Other particularly suitable nanoparticles are selected from doped quantum dots as core, such as ZnSe:Mn/ZnS, or ZnSe:Cu/ZnS.

[0113] Other particularly suitable nanoplates are selected from ZnTe/ZnSe.sub.yS.sub.(1-y), ZnSe.sub.xTe.sub.(1-x)/ZnS, ZnSe.sub.xTe.sub.(1-x)/ZnSe, ZnSe.sub.xTe.sub.(1-x)/ZnSe.sub.yS.sub.(1-y), where x and y are rational numbers between 0 (excluded) and 1 (excluded).

[0114] In an advantageous embodiment, semi-conductive nanoparticles have a largest dimension below 100 nm, in particular below 50 nm, ideally below 20 nm. Semi-conductive nanoparticles of small size do not induce light scattering when dispersed in a material having a different refractive index.

[0115] In an embodiment, the amount of semi-conductive nanoparticles in the filtering film is in a range from 0.5 wt % to 15 wt %, based on the weight of the filtering film, for a 10 m-thick film, preferably from 1 wt % to 12 wt %, more preferably from 1.5 wt % to 10 wt %.

[0116] Semi-conductive nanoparticles of II-VI type and comprising a core based on zinc, sulfur and selenium are especially suitable as compounds absorbing UV-light when used with a concentration from 0.5 wt % to 8 wt %.

[0117] In an embodiment, the semi-conductive nanoparticles are capped with an organic layer, an inorganic layer or a mixture thereof.

Composite Particles

[0118] In an embodiment, the semi-conductive nanoparticles are encapsulated in an encapsulating material, leading to composite particles. By encapsulating material, it is meant a material that covers all surface of semi-conductive nanoparticles. In other words, encapsulating material forms a barrier around the semi-conductive nanoparticles. Such a barrier as several advantages. In particular, said semi-conductive nanoparticles may be protected against chemicals, e.g., moisture, oxidants. Besides, semi-conductive nanoparticles that are not dispersible in a medium may be encapsulated in a material whose compatibility with said medium is good: the barrier behaves as a compatibilization agent. In addition, encapsulated semi-conductive nanoparticles may be under the form of a powder dispersible in a medium instead of a dispersion in a solvent, thereby providing with easier handling. Last, the encapsulating material may have a role of refractive index matching, in order to lower diffusion or haze: indeed, when semi-conductive nanoparticles are dispersed in a matrix, haze is proportional to the difference of refractive index between the matrix and the dispersed nanoparticles. Adding an encapsulating material with an intermediate refractive index mitigates this effect and lowers haze.

[0119] The encapsulating material may be an organic material or an inorganic material. For instance, the organic material may be selected from allyl polymers, (meth)acrylic polymers; epoxy compounds; polyurethane, polyester, polythiourethane materials, or mixture thereof. For instance, the inorganic material may be selected from sol gel materials, metal oxide materials, mineral oxides, or mixture thereof.

[0120] Suitable inorganic material may be selected from the group consisting of SiO.sub.2, Al.sub.2O.sub.3, TiO.sub.2, ZrO.sub.2, HfO.sub.2, GeO.sub.2, SnO.sub.2, or a mixture thereof, including for instance Al.sub.yZr.sub.zO with

[00005]$\frac{3}{2}y+2z=1.$

In an embodiment, the encapsulating material does not consist of pure SiO.sub.2.

[0121] In an embodiment, the encapsulating material does not absorb UV-light, and absorbance of the filtering film is only defined by semi-conductive nanoparticles. Alternatively, the encapsulating material does absorb UV-light, and absorbance of the filtering film is defined by the sum of absorbance of semi-conductive nanoparticles and absorbance of encapsulating material.

[0122] In an embodiment, the loading charge of the semi-conductive nanoparticles in the composite particle is at least 1%, preferably at least 2.5%, more preferably at least 5%, said loading charge being the mass ratio between the mass of semi-conductive nanoparticles comprised in a composite particle and the mass of said composite particle. Indeed, the performance of composite particles is proportional to the concentration of semi-conductive nanoparticles they contain. Therefore, a high concentration of semi-conductive nanoparticles is advantageous. It has to be noted however that increasing concentration of semi-conductive nanoparticles without degrading their propertiesas a consequence of aggregation or manufacturing process for instanceis not easy.

[0123] The composite particles may be in the form of a monodisperse population. Monodisperse composite particles are advantageous for various reasons, depending on the domain of application. When composite particles are used in filtering films, a homogeneous size distribution avoids uncontrolled light diffusion and ensures spatial homogeneity of the filtering film.

[0124] In an embodiment, composite particles have a largest dimension below 500 nm, in particular below 300 nm, ideally below 200 nm.

[0125] The mean size of the composite particles is preferably in a range from 50 nm to 500 nm, more preferably from 50 nm to 250 nm. Composite particles having a mean size from 50 nm to 250 nm, preferably from 50 nm to 100 nm are especially suitable to obtain filtering films with high transparency and low haze.

[0126] The composite particles may be chemically modified on their surface. Chemical modification may be obtained by grafting, by adsorption of molecules or by physical processesheat, vacuum or gaseous treatment. Chemical modification may use compatibilization agents, allowing to mix composite particles in complex formulationssuch as resins, varnishes, paints, colloidal dispersion, polymerizable compositions . . . without aggregation or phase separation of the composite particles.

Organic Compounds Absorbing UV-Light

[0127] As an alternative to semi-conductive nanoparticles, compounds absorbing UV-light may be organic anti-UV compounds.

[0128] Especially suitable organic anti-UV compounds may be selected in the group consisting of benzotriazoles, triazines, piperidines, benzophenones, catechol, their derivatives, and mixtures thereof.

[0129] Suitable benzotriazoles are derivatives of (2H-benzotriazol-2-yl)-4-hydroxybenzene such as Sodium 3-(2H-benzotriazol-2-yl)-5-sec-butyl-4-hydroxybenzenesulfonateCAS number 92484-48-5or Polyethylene glycol mono-3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)-1-oxopropyl etherCAS number 104810-48-2or Polyethylene glycol di[3-[3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]-1-oxopropyl] etherCAS number 104810-47-1or Benzenepropanoic acid, 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy-, C7-9-branched and linear alkyl estersCAS number 127519-17-9or 2-(2H-Benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl) phenolCAS number 73936-91-1.

[0130] Suitable triazines are reaction products of 1,3-Benzenediol, 4-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl] with [(dodecyloxy)methyl]oxirane and oxirane mono[(C10-16-alkyloxy)methyl] derivativesCAS number 153519-44-9or Isooctyl 2-[4-[4,6-bis[(1,1-biphenyl)-4-yl]-1,3,5-triazin-2-yl]-3-hydroxyphenoxy]propanoateCAS number 204848-45-3or triazine know as TINUVIN477 supplied by BASF.

[0131] A suitable piperidines is bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacateCAS number 129757-67-1.

[0132] A mixture of bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacateCAS number 129757-67-1and reaction products of 1,3-Benzenediol, 4-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl] with [(dodecyloxy)methyl]oxirane and oxirane mono[(C10-16-alkyloxy)methyl] derivativesCAS number 153519-44-9known under tradename Eversorb AQ8 is especially suitable.

[0133] Other suitable organic anti-UV compounds are avobenzones, such as 1,3-Propanedione, 1-[4-(1,1-dimethylethyl)phenyl]-3-(4-methoxyphenyl)CAS number 70356-09-1or the compound known under tradename Parsol guard.

[0134] Among these organic anti-UV compounds, those having an absorption peakeither principal or secondaryin the range from 300 nm to 340 nm are preferred. In particular, Tinuvin 384-2, Eversorb AQ8 and Tinogard HS are suitable.

[0135] The following mixture of organic anti-UV compounds is also suitable: Tinuvin 384-2; Parsol Guard and Eversorb AQ8 in 1:1:1 proportion.

[0136] In an embodiment, the amount of organic anti-UV compounds in the filtering film is in a range from 2 wt % to 15 wt %, based on the weight of the filtering film, for a 10 m-thick film, preferably from 2.5 wt % to 12 wt %, more preferably from 3 wt % to 10 wt %.

[0137] In an embodiment, compounds absorbing UV-light comprise a mixture of one or more semi-conductive nanoparticles and/or one or more organic anti-UV compounds. In this embodiment, the amount of compounds absorbing UV-light in the filtering film is in a range from 3 wt % to 15 wt %, based on the weight of the filtering film, for a 10 m-thick film.

[0138] In an embodiment, the compounds absorbing UV-light do not comprise more than 2.5 wt %, based on the weight of the filtering film, for a 10 m-thick film, of core-shell semi-conductive nanoparticles comprising: [0139] a core of ZnSe.sub.xS.sub.(1-x) material where x is in a range from 0.60 to 0.98, and [0140] a shell of ZnS material,
and having a local maximum absorbance of highest wavelength in the range from 350 to 500 nm.

[0141] More preferably, the compounds absorbing UV-light do not comprise core-shell semi-conductive nanoparticles comprising: [0142] a core of ZnSe.sub.xS.sub.(1-x) material where x is in a range from 0.60 to 0.98, and [0143] a shell of ZnS material,
and having a local maximum absorbance of highest wavelength in the range from 350 to 500 nm.

Binder:

[0144] In the disclosure, the filtering film comprises a binder. This binder may be of various polymer types, for instance selected among poly(methyl methacrylate) (PMMA), poly(butyl methacrylate), poly(lauryl methacrylate), poly(vinyl butyral), poly(vinyl acetate), poly(ethylene vinyl acetate), thermoplastic polyurethane, cellulose, ionoplast, polycarbonate, poly(ethylene vinyl alcool), polyester/melamine adducts, silicone, polyphenylmethylsiloxane, polyphenylalkylsiloxane, polydiphenylsiloxane, polydialkylsiloxane, fluorinated silicone, vinyl and hydride substituted silicone, divinylbenzene, or a mixture thereof

[0145] The filtering film may be obtained from a thermoplastic polymer, in which compounds absorbing UV-light are dispersed, typically during melting/extrusion/stretching process. The thickness of the filtering film is here controlled by the fabrication process.

[0146] Alternatively, the filtering film may be obtained from a polymerizable composition, in which compounds absorbing UV-light are dispersed. Then, the polymerizable composition is curedthermally, actinically or by any other curing meanor dried to yield a film. In this case, the polymerizable composition may comprise a solvent.

[0147] In an embodiment, the film is obtained by curing a Sol-Gel polymerizable composition and has a thickness in a range from 1 m to 15 m, preferably from 1 m to 10 m, more preferably from 2 m to 6 m.

[0148] In one embodiment, the film is obtained by curing a composition comprising (meth)acrylics monomers or oligomers, epoxy monomers or oligomers, or mixture thereof. In particular, the thickness of coating obtained by curing said polymerizable composition is in a range from 2 m to 100 m, preferably from 3 m to 50 m, more preferably from 4 m to 30 m.

Packaging:

[0149] This disclosure also relates to a packaging, for instance a packaging selected from the group of glass containers, glass bottles, plastic containers and plastic bottles, especially a light filtering glass container.

[0150] In the disclosure, the filtering film may be a self-standing material or may be laid on a substrate to form a packaging. Especially interesting substrates are glass containers, in order to form light filtering glass containers.

[0151] To this end, a filtering film may be deposited on the surface of the substrate. Adhesion between substrate and filtering film may be provided by an adhesive, or by the tacky properties of the filtering film itself.

[0152] Alternatively, a polymerizable composition may be coated on the surface of the substrateby any method such as spray coating or dip coating for instanceand cured or dried to obtain the filtering film.

[0153] Last, the filtering film may be used directly to form a packaging. In this case, the thickness for the filtering film may be in a range from 50 m to 3 mm.

UseMethod of Protection:

[0154] This disclosure also relates to the use of a filtering film as disclosed hereabove as a protection against UV-light in a range from 300 nm to 340 nm.

[0155] For instance, a substrate may be covered with a filtering film as disclosed hereabove. Then, the substrate may be disposed around the product to be protected. In particular, the substrate may be a glass container, and the productfood, cosmetic or fragrance for instancemay be filled inside the glass container to be protected against UV-light.

[0156] Alternatively, the filtering film may be formed into a packaging, in which the product is filled, wrapped or otherwise contained.

[0157] This disclosure also relates to a method of protection of a consumer good against UV-light in a range from 300 nm to 340 nm comprising enclosing the consumer good in a filtering film as disclosed hereabove. The consumer good may be selected from food productsin either solid or liquid formcosmetic formulations or fragrances. Said filtering film may be covering a packaging in which the consumer good is contained. This method of protection is especially suitable for bottles for perfumes/fragrances.

EXAMPLES

[0158] The present invention is further illustrated by the following examples.

Absorption Curve of Filtering Films:

[0159] A filtering film is prepared by application on a glass plate of 250 L of a liquid composition with a cube coater, to obtain a 100 m thick coating, then cured 12 minutes in an oven at 180 C., yielding a 10 m thick dry film.

[0160] The thickness of the film is controlled by a profilometer then absorbance of the film is measured. The absorbance of the glass plate is subtracted to obtain the absorbance of the sole filtering film.

Ageing Test:

[0161] In order to assess the protection of the filtering films, the following protocol is used.

[0162] A bottle is coated with a polymerizable composition then cured. After cure, the filtering film is 10 m thick.

[0163] The UV-visible absorbance spectrum of a composition under studyeither food, cosmetic formulation or fragranceis measured.

[0164] Then, the bottle is filled with the composition under study and the bottle is placed under constant illumination corresponding to D65 illuminantthus including UV light from 300 nm wavelengthwith 550 W/m.sup.2 total power during 24 hours at 40 C. temperaturereferred to as SUNTEST.

[0165] During the SUNTEST, the UV-visible absorbance value at 500 nm of the aged composition is measured and compared with the spectrum before SUNTEST.

[0166] The comparison of spectra before and during SUNTEST allows to determine if the composition under study has been protected by the filtering film or not.

[0167] FIG. 5 shows the UV-visible spectrum A0 of a fragrance before SUNTEST. D0-6 h represents the spectrum of the fragrance devoid of any UV protection after 6 hours. Dref_add-6 h represents a fragrance comprising an additivemainly avobenzoneafter 6 hours setting the standard protection of the industry. Note that the spectrum below 430 nm is slightly different due to the presence of the additive. Dref_coat-6 h represents a fragrance protected by the reference coating of comparative example: the protection is not appropriate. Finally, DEx3-6 h represents a fragrance protected by the filtering film of example 3: protection is better than the reference coating and approaches the standard of industry.

[0168] FIG. 6 presents the relative decrease of absorbance at 500 nm for a fragrance during a SUNTEST. DO represents a fragrance devoid of UV protection: a strong and quick degradation is observed. Dref_add represents a fragrance comprising an additivemainly avobenzonesetting the standard protection of the industry. Dref_coat represents a fragrance protected by the reference coating of comparative example: the protection is not appropriate. DEx3 represents a fragrance protected by the filtering film of example 3: protection is similar to the standard of industry.

[0169] In addition, a visual comparison of the colour of the composition before and after SUNTEST is used for coloured samples. A visually detectable change in colour lead to a FAIL classification of the filtering film.

Comparative Example

[0170] Two commercial bottles used for fragrance and comprising a filtering film are used. The first bottle is cleaned in order to remove the filtering film. The second bottle is used without intervention.

[0171] The absorption of the filtering film is measured by difference of absorption between second bottle and first bottle. The absorption curve is shown in FIGS. 3 and 4dotted line. The corresponding values for A.sub.380 and A.sub.340 are 1.8 and 1.8 respectively.

[0172] In SUNTEST, the commercial bottle is not satisfactory: changes in UV-visible absorption spectrumsee FIG. 5and colour of the fragrance are observed.

Example 1

[0173] 5 wt % of organic absorber Tinuvin 384-2 and 5 wt % of core shell semi-conductive nanoparticles SC #1 are added in a waterborne polyester resin (75 parts)hexamethoxymethyl melamine (25 parts) polymerizable compositionhereafter Ref binderthen cured. After cure, the filtering film is 10 m thick. The core of the semi-conductive nanoparticles has a diameter of 3.0 nm and formula ZnSe.sub.xS.sub.(1-x) with x about 0.94 and a shell of ZnS of mean thickness 1.3 nm. .sub.max for SC #1 is about 400 nm.

[0174] The absorption curve is shown in FIG. 3. The corresponding values for A.sub.380 and A.sub.340 are 2.8 and 2.8 respectively.

[0175] In SUNTEST, bottle of example 1 is satisfactory: a fragrance devoid of UV-stabilizer is not degradedsee FIG. 5.

Examples 2-7

[0176] Example 1 is reproduced, but composition of compounds absorbing UV-light is changed according to the following table (in weight %, based on the weight of the filtering film):

TABLE-US-00002 TABLE II Semi- conductive Organic nano- anti-UV Ex particles wt % compounds wt % A.sub.380 A.sub.340 SUNTEST 1 SC#1 5 Tinuvin 384-2 5 2.8 2.8 PASS 2 SC#1 1.1 Tinuvin 384-2 5 PASS 3 SC#1 1.1 Tinuvin 384-2 7.5 3.6 3.7 PASS 4 Tinuvin 384-2 5 2.4 2.4 PASS 5 SC#1 4.6 Tinogard HS 1.3 3 3.2 PASS 6 SC#1 1.1 Tinuvin 384-2 5 PASS Tinuvin 249 1.3 7 SC#1 1.1 Tinuvin 384-2 10 PASS Tinuvin 249 2.6

Examples 10-133

[0177] Further examples are reproduced, but composition of compounds absorbing UV-light is changed according to the following table III (in weight %, based on the weight of the filtering film). Film thickness is also changed to be either 10 m, 12 m or 15 m. All these films show values for A.sub.380 greater than 2 and PASS the SUNTEST.

[0178] Solvent-borne compositions are based on Ref binder of example 1. Water-borne compositions are based on saturated polyesters with a dry extract of 30% in water and less than 10% of polar co-solvents.

[0179] An Ecotox assessment is also made for these compositions. Examples compliant with Ecotox do not require any labelling.

TABLE-US-00003 TABLE III Thickness Example Resin Ecotox (m) A.sub.380 SC#1 T384-2 T479 T477 E109 10 Refbinder 15 5.06 0.10% 10.2% 11 Ref binder comply 15 3.96 0.10% 2.8% 2.8% 2.8% 12 Ref binder comply 15 4.34 0.10% 2.8% 2.8% 13 Ref binder comply 15 3.82 0.10% 2.8% 4.1% 2.2% 14 Ref binder comply 15 4.13 0.10% 2.8% 2.0% 15 Ref binder 15 4.15 0.10% 3.6% 1.7% 16 Ref binder 15 4.45 0.10% 3.6% 0.8% 0.8% 17 Ref binder comply 15 4.24 0.10% 2.8% 2.0% 18 Ref binder 15 4.68 0.10% 3.8% 2.0% 19 Ref binder 15 4.35 0.10% 3.8% 0.8% 2.0% 20 Ref binder 15 4.32 0.10% 6.7% 1.4% 21 Ref binder 15 4.50 0.10% 6.7% 0.6% 22 Ref binder 15 4.47 0.10% 4.1% 2.0% 23 Ref binder 15 4.39 0.10% 5.4% 1.4% 24 Ref binder 15 3.86 0.10% 4.1% 2.2% 2.2% 25 Ref binder 15 4.75 0.10% 5.4% 2.0% 1.7% 26 Ref binder 15 4.23 0.10% 5.4% 2.0% 2.0% 27 Ref binder 15 5.44 0.10% 4.1% 2.8% 2.8% 28 Ref binder 15 4.53 0.10% 4.4% 2.0% 2.8% 29 Ref binder 15 3.93 0.10% 4.1% 2.8% 30 Ref binder 15 4.93 0.10% 5.4% 2.2% 31 Ref binder 15 4.96 10.3% 32 Ref binder comply 15 3.88 2.8% 2.8% 2.8% 33 Ref binder comply 15 4.25 2.8% 2.8% 34 Ref binder comply 15 3.75 2.8% 4.1% 2.2% 35 Ref binder comply 15 4.05 2.8% 2.0% 36 Ref binder 15 4.07 3.6% 1.7% 37 Ref binder 15 4.36 3.6% 0.8% 0.8% 38 Ref binder comply 15 4.16 2.8% 2.0% 39 Ref binder 15 4.58 3.8% 2.0% 40 Ref binder 15 4.26 3.8% 0.8% 2.0% 41 Ref binder 15 4.23 6.7% 1.4% 42 Ref binder 15 4.41 6.7% 0.6% 43 Ref binder 15 4.38 1% 4.1% 2.0% 44 Ref binder 15 4.30 1% 5.4% 1.4% 45 Ref binder 15 3.79 1% 4.1% 2.2% 2.2% 46 Ref binder 15 4.66 1% 5.4% 2.0% 1.7% 47 Ref binder 15 4.14 1% 5.4% 2.0% 2.0% 48 Ref binder 15 5.33 1% 4.1% 2.8% 2.8% 49 Ref binder 15 4.44 1% 4.4% 2.0% 2.8% 50 Ref binder 15 3.85 5% 4.1% 2.8% 51 Ref binder 15 4.83 5% 5.4% 2.2% 52 Ref binder 15 5.21 5% 10.2% 53 Ref binder comply 15 7.08 5% 2.7% 2.7% 2.7% 54 Ref binder comply 15 4.47 5% 2.7% 2.7% 55 Ref binder 15 4.82 5% 3.8% 1.9% 56 Ref binder 15 4.45 5% 6.6% 1.4% 57 Ref binder 15 4.05 4.1% 2.7% 58 Ref binder 15 5.08 5.3% 2.2% 59 Ref binder 15 6.32 9.8% 60 Ref binder comply 15 8.59 2.6% 2.6% 2.6% 61 Ref binder comply 15 5.42 2.6% 2.6% 62 Ref binder 15 5.85 3.6% 1.9% 63 Ref binder 15 5.40 6.3% 1.3% 64 Ref binder 15 4.92 3.9% 2.6% 65 Ref binder 15 6.17 5.1% 2.1% 66 Ref binder comply 10 2.45 3.3% 67 Ref binder 10 2.65 5.4% 68 Ref binder 10 2.41 5.4% 69 Ref binder 10 2.68 70 Ref binder 10 2.87 6.7% 71 Ref binder 10 2.92 72 Ref binder comply 10 3.21 2.8% 2.8% 73 Ref binder comply 10 3.01 2.2% 1.4% 2.2% 74 Ref binder comply 10 2.98 2.8% 2.2% 75 Ref binder 10 3.45 76 Ref binder comply 10 3.86 77 Ref binder 10 2.45 78 Ref binder 10 2.65 79 Ref binder comply 10 3.17 80 Ref binder comply 10 2.64 81 Ref binder comply 10 3.09 2.8% 82 Ref binder comply 10 3.39 2.8% 2.8% 83 Ref binder comply 10 2.56 1.4% 84 Ref binder comply 10 2.38 85 Ref binder comply 10 2.60 2.8% 86 Ref binder comply 10 3.07 2.8% 87 Ref binder comply 10 2.73 2.8% 88 Ref binder comply 12 5.56 2.8% 89 Ref binder comply 12 2.92 2.8% 90 Ref binder comply 12 6.21 91 Ref binder comply 12 5.14 1.4% 1.4% 92 Ref binder comply 12 6.70 2.8% 2.8% 93 Ref binder comply 12 6.85 2.8% 2.8% 94 Ref binder comply 12 4.79 2.8% 95 Ref binder comply 12 4.93 2.8% 96 Ref binder comply 12 4.56 2.8% 97 Ref binder comply 12 4.70 2.8% 98 Ref binder 12 2.64 99 Ref binder 12 4.25 5.4% 100 Ref binder 12 5.57 10.3% 101 Ref binder comply 12 6.21 102 Ref binder comply 12 4.54 2.8% 2.8% 103 Ref binder comply 12 5.81 5.4% 104 Ref binder comply 12 7.18 2.8% 105 Ref binder 12 5.65 7.9% 2.8% 106 Ref binder comply 12 6.12 2.8% 107 Ref binder comply 12 6.27 2.8% 108 Ref binder comply 12 7.40 5.4% 4.1% 109 Ref binder comply 12 7.07 2.8% 110 Waterborne comply 10 2.45 3.3% 111 Waterborne comply 10 2.65 5.4% 112 Waterborne comply 10 2.41 5.4% 113 Waterborne comply 10 2.68 114 Waterborne 10 2.87 6.7% 115 Waterborne comply 10 3.39 2.8% 2.8% 116 Waterborne comply 10 3.21 2.8% 2.8% 117 Waterborne comply 10 3.01 2.2% 1.4% 2.2% 118 Waterborne comply 10 2.98 2.8% 2.2% 119 Waterborne comply 10 2.56 1.4% 120 Waterborne comply 10 2.38 121 Waterborne comply 10 2.60 2.8% 122 Waterborne comply 10 3.07 2.8% 123 Waterborne comply 10 2.73 2.8% 124 Ref binder 10 4.63 10.3% 125 Ref binder comply 10 5.15 126 Ref binder comply 10 3.77 2.8% 2.8% 127 Ref binder comply 10 4.82 5.4% 128 Ref binder comply 10 5.96 2.8% 129 Ref binder 10 4.69 7.9% 2.8% 130 Ref binder comply 10 5.08 2.8% 131 Ref binder comply 10 5.20 2.8% 132 Ref binder comply 10 6.15 5.4% 4.1% 133 Ref binder comply 10 5.87 2.8% Example T400 E-BL1B T234 T928 T1130 T M T S A + O 10 11 12 4.1% 13 14 4.1% 15 5.4% 16 5.4% 17 5.4% 18 4.6% 19 4.6% 20 2.2% 21 0.8% 22 4.1% 23 2.2% 24 25 26 27 28 2.8% 29 5.4% 30 4.1% 31 32 33 4.1% 34 35 4.1% 36 5.4% 37 5.4% 38 5.4% 39 4.6% 40 4.6% 41 2.2% 42 0.8% 43 4.1% 44 2.2% 45 46 47 48 49 2.8% 50 5.4% 51 4.1% 52 53 54 4.1% 55 4.6% 56 2.2% 57 5.3% 58 4.1% 59 60 61 3.9% 62 4.4% 63 2.1% 64 5.1% 65 3.9% 66 67 68 69 6.7% 70 71 7.9% 72 73 74 2.2% 75 6.7% 76 7.9% 77 5.4% 78 6.7% 79 2.8% 80 4.1% 1.4% 81 1.4% 82 83 3.3% 84 2.2% 3.3% 85 2.8% 86 4.1% 87 1.4% 88 6.7% 0.0% 89 2.8% 90 10.3% 91 5.4% 92 2.8% 93 2.8% 94 5.4% 95 5.4% 96 5.4% 97 5.4% 98 10.3% 99 5.4% 100 101 10.3% 102 2.8% 103 5.4% 104 5.4% 5.4% 105 106 7.9% 107 7.9% 108 109 7.9% 2.8% 110 111 112 113 6.7% 114 115 116 117 118 2.2% 119 3.3% 120 2.2% 3.3% 121 2.8% 122 4.1% 123 1.4% 124 125 10.3% 126 2.8% 127 5.4% 128 5.4% 5.4% 129 130 7.9% 131 7.9% 132 133 7.9% 2.8%

[0180] Organic UV compounds used in examples 10-133 are referenced as follow:

TABLE-US-00004 TABLE IV Ref Tradename CAS Molecule active T384-2 Tinuvin 384-2 127519-17-9 Benzenepropanoic acid, 3-(2H-benzotriazol-2-yl)- 5-(1,1- dimethylethyl)-4-hydroxy-, C7-9-branched and linear alkyl esters T477 Tinuvin 477 1-isoctyloxycarbonyl ethylated 2,4,6 tris (2,4- hydroxyphenyl) -1,3,5 triazine derivatives T479 Tinuvin 479 Hydroxyphenyl-triazine T234 Tinuvin 900 70321-86-7 2-(2H-benzotriazol-2-yl)-4, 6-bis (1-methyl-1- phenylethyl)phenol T928 Tinuvin 928 73936-91-1 2-(2H-Benzotriazol-2-yl)-6-(1-methyl-1- phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol T1130 Tinuvin 1130 104810-47-1 -[3-(2-H-Benzotriazole-2-yl)-4-hydorxy-5- tertbutylphenyl]-propionic acid-poly(ethylene glycol) 300-ester/Bis{-[3-(2-H-Benzotriazole-2- yl)-4-hydroxy-5tertbutylphenyl]-propionic acid}- poly(ethylene glycol) 300 -ester T400 Tinuvin 400 153519-44-9 1,3-Benzenediol, 4-[4,6-bis(2,4-dimethylphenyl)- 1,3,5-triazin-2-yl] E109 Eversorb 109 83044-89-7/ Octyl 3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H- 83044-90-0 benzotriazol-2-yl)phenyl]propionate E-BL1B Eversorb 131-55-5 2,2,4,4-Tetrahydroxybenzo-phenone BL1B A + O Parsol Guard 70356-09-1/ 1,3-Propanedione, 1-[4-(1,1- 6197-30-4 dimethylethyl)phenyl]-3-(4-methoxyphenyl)/2- cyano-3,3-diphnylacrylate de 2-thylhexyle T-M Tinosorb M 103597-45-1 2,2-methylenebis(6-(2H-benzotriazol-2-yl)-4- (1,1,3,3-tetramethylbutyl)phenol) T-S Tinosorb S 187393-00-6 5-[(2-ethylhexyl)oxy]-2-(4-{4-[(2-ethylhexyl)oxy]- 2-hydroxyphenyl}-6-(4-methoxyphenyl)-1,3,5- triazin-2-yl)phenol