Glass assembly comprising temporary organic protective layer

Abstract

The present invention relates to a glazing material comprising a substrate coated with a functional coating and a temporary organic protective layer deposited on at least a portion of the functional coating. The protective layer is obtained by crosslinking a polymerizable composition comprising (a) a (meth) acrylate compound and (b) optionally a polymerization initiator. The temporary organic protective layer has a weight loss of greater than 65% by thermogravimetric analysis (TGA) from 30 DEG C to 450 DEG C in air at a heating rate of 10 DEG C / min.

Description

[0001] This invention relates to materials comprising transparent substrates coated with functional coatings that can affect solar radiation and / or infrared radiation. The invention also relates to assembly glass comprising these materials, and the use of such materials in the manufacture of assembly glass.

[0002] In the following description, such as “functional coating”, the term “functional” means “capable of influencing solar radiation and / or infrared radiation”.

[0003] Due to the advantageous properties of these functional coatings in conducting electricity and reflecting infrared (IR) radiation, they are used in so-called "sunshine control" glazing aimed at reducing the amount of solar energy entering and / or so-called "low-emissivity" glazing aimed at reducing the amount of energy dissipated to the exterior of buildings or vehicles.

[0004] A functional coating comprises one or more functional layers. These functional layers may be based on conductive oxides or metal layers.

[0005] Functional coatings based on conductive oxides are typically based on ITO (indium tin oxide). These coatings feature low emissivity, good chemical durability, and good mechanical resistance. However, such functional coatings are relatively expensive.

[0006] Functional coatings containing one or more silver-based metallic functional layers (hereinafter referred to as silver-based functional coatings) are significantly cheaper. However, these functional coatings typically have insufficient corrosion resistance and mechanical resistance. This low strength is reflected in the appearance of defects such as pitting, scratches, and even complete or partial tearing of the coating during use under standard conditions in the short term. All defects or scratches, whether due to corrosion or mechanical stress, are likely to affect not only the attractiveness of the coated substrate but also the levels of optical and energy performance.

[0007] Applications WO 2015 / 019022 and WO 2018 / 051029 disclose a substrate provided with a functional coating that reflects infrared radiation, the functional coating covering a temporary protective layer that is intended to be removed after a tempering-type heat treatment. These temporary protective coatings are acrylate-based organic polymer coatings with a thickness of 10 to 20 μm. These thick temporary protective layers prevent any scratches from forming on the functional coating they protect. These layers are removed during the heat treatment.

[0008] The solutions developed in these documents can be further improved. In particular, the following inconveniences are sometimes observed: - This temporary layer does not always burn completely, especially when the thermal degradation rate is too low relative to the duration and / or temperature of the heat treatment. - Sometimes it produces an unpleasant odor, especially in tempering furnaces.

[0009] Document WO 2019 / 123477 discloses a temporary protective layer based on (meth)acrylate compounds comprising solid particles such as polymer beads or glass beads. The solid particles serve as a substitute for expensive oligomeric (meth)acrylate compounds, as well as as a substitute for spacers and / or powders used between two glass substrates to prevent friction or adhesion, especially during storage.

[0010] Surprisingly, the applicant has discovered that these drawbacks can be avoided by using a polymeric protective layer based on specific acrylates, particularly comprising a high proportion of acrylate compounds with defined molecular weights and functionalities. This layer exhibits a faster degradation rate and a lower degradation temperature. The layer effectively protects the coated substrate from any defects or scratches and is easier to remove during heat treatment.

[0011] The present invention thus relates to materials comprising a substrate coated with a functional coating and a temporary organic protective layer deposited on at least a portion of the functional coating, the protective layer comprising a polymer matrix obtained by a crosslinking polymerizable composition comprising (a) a (meth)acrylate compound and (b) optionally a polymerization initiator, characterized in that: The temporary organic protective layer has a weight loss of more than 65%, preferably more than 70%, or even more than 75% obtained by thermogravimetric analysis (TGA) at a heating rate of 10°C / min in air, obtained from 30°C to 450°C. The polymerizable composition may comprise a (meth)acrylate compound (a1) containing at least one alkyleneoxy group and having a molecular weight of 100 to 800 g / mol. Preferably, these (meth)acrylate compounds (a1) constitute at least 30% by mass of the total mass of the protective layer.

[0012] The present invention also relates to a material comprising a substrate coated with a functional coating and a temporary organic protective layer deposited on at least a portion of the functional coating, the protective layer comprising a polymer matrix obtained by a crosslinking polymerizable composition comprising (a) a (meth)acrylate compound and optionally (b) a polymerization initiator, characterized in that the polymerizable composition comprises a (meth)acrylate compound (a1) containing at least one alkyleneoxy group and having a molecular weight of 100 to 800 g / mol, wherein the (meth)acrylate compound (a1), once crosslinked, accounts for at least 30% by mass of the total mass of the protective layer.

[0013] There exist the same temporary organic protective layer defined in two different ways, in particular: - By the percentage of ATG degradation at a given temperature, - By the proportion of (meth)acrylate compounds with a defined molecular weight.

[0014] The present invention also relates to materials comprising a substrate coated with a functional coating and a temporary organic protective layer deposited on at least a portion of the functional coating, the protective layer being obtained by a crosslinkable polymerizable composition comprising (a) a (meth)acrylate compound and optionally (b) a polymerization initiator, characterized in that: The total mass of the protective layer comprises at least 50%, at least 60%, or at least 70% of a (meth)acrylate compound with a molecular weight of 100 to 800 g / mol, preferably 100 to 500 g / mol.

[0015] The organic protective layer is an organic polymer layer. It is essentially organic in nature. It is obtained from a polymerizable composition. It is produced by the crosslinking of polymerizable organic compounds present in the polymerizable composition.

[0016] The (meth)acrylate compound (a) and optionally the polymerization initiator (b) react with each other, and once crosslinked, form an organic polymer matrix. This corresponds to the mass ratio of the organic polymer matrix when considering that the protective layer comprises a certain mass ratio of the (meth)acrylate compound (a) and optionally the polymerization initiator (b). The polymerization initiator, if present, is incorporated into the resulting organic matrix.

[0017] The polymer matrix comprises at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or 100% by mass of the total mass of the protective layer. The polymer matrix is ​​obtained by crosslinking a polymerizable composition comprising (a) a (meth)acrylate compound and optionally (b). This means that these percentages may also correspond to the proportions of compounds (a) and (b) that have reacted with each other. Compounds (a) and (b) that have reacted with each other comprise at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or 100% by mass of the polymer matrix. Compounds (a) and (b) that have reacted with each other constitute at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or 100% by mass of the organic protective layer.

[0018] The present invention also relates to a method for obtaining a material that can be processed at high temperatures, the material comprising a substrate coated with a functional coating, the method comprising the following steps: The steps for protecting the article include: - Prepare a polymerizable composition comprising (a) a (meth)acrylate compound and optionally (b) a polymerization initiator, wherein the (meth)acrylate compound (a1) contains at least one alkylene group and has a molecular weight of 100 to 800 g / mol, and the (meth)acrylate compound (a1) constitutes at least 30% by mass of the total mass of the protective layer. - The polymerizable composition is applied to at least a portion of the functional coating with a thickness of at least 1 micrometer. - Crosslink the composition to form a temporary organic protective layer. The same step of heat treatment and deprotection of the article includes: - The temporary protective layer is removed by heat treatment at a temperature above 200°C, sufficient to achieve tempering of the article.

[0019] The present invention also relates to a method for obtaining a material that can be processed at high temperatures, the material comprising a substrate coated with a functional coating, the method comprising the following steps: The steps for protecting the article include: - To prepare a polymerizable composition comprising (a) a (meth)acrylate compound and optionally (b) a polymerization initiator, - The polymerizable composition is applied to at least a portion of the functional coating with a thickness of at least 1 micrometer. - Crosslink the composition to form a temporary organic protective layer. The same step of heat treatment and deprotection of the article includes: - The temporary protective layer is removed by heat treatment at a temperature above 200°C, sufficient to achieve tempering of the product. The temporary organic protective layer is characterized by having a weight loss of more than 65%, preferably more than 70%, or even more than 75% in air at a rate of 10°C / min, obtained by thermogravimetric analysis (TGA) from 30°C to 450°C.

[0020] According to the method, the functional coating is preferably deposited by magnetron sputtering, and is characterized in that the temporary protective layer is in direct contact with the functional coating.

[0021] The term "(meth)acrylate" is understood to refer to acrylate or methacrylate. The expression "(meth)acrylate functional" is understood to refer to acrylate functional (CH2=CH-COO-) or methacrylate functional (CH2=CH(CH3)-COO-).

[0022] The proportions of (meth)acrylate compounds that have reacted with each other, in ascending order of mass, relative to the total mass of the organic protective layer are: - At least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, and / or - Up to 99%, up to 98%, up to 97%, up to 96%, up to 95%.

[0023] The term "(meth)acrylate compound" is understood to refer to an ester of acrylic acid or methacrylic acid containing at least one (meth)acrylate functional group. The (meth)acrylate compounds used according to the present invention can be selected from monofunctional and polyfunctional (meth)acrylates, such as monofunctional, difunctional, trifunctional, and polyfunctional (meth)acrylates. These esters can be monomers, oligomers, prepolymers, or polymers. When subjected to polymerization conditions, these (meth)acrylate compounds produce polymer networks endowed with a solid structure.

[0024] The (meth)acrylate compound has a molecular weight or average molecular weight (hereinafter referred to as molecular weight) of 100 to 800 g / mol.

[0025] According to the present invention, the (meth)acrylate compound is selected from esters of acrylic acid or methacrylic acid.

[0026] The expression "(meth)acrylate compound containing one alkylene group" is understood to refer to a (meth)acrylate compound containing one or more alkylene groups. The expression "alkylene group" is understood to refer to a compound of formula -[(C n H 2n The alkylene group is a chemical group consisting of an allylene group bonded to an oxygen atom, preferably wherein n is 1 to 6. This definition does not include groups that participate in the formation of one or more ester groups of acrylic acid or methacrylic acid. Preferably, the alkylene group is selected from the oxyvinyl group -CH2-CH2-O- and the oxypropylene groups -CH2-CH2-CH2-O-, -CH(CH3)-CH2-O- and -CH2-CH(CH3)-O-.

[0027] The expression “(meth)acrylate compound (a1)” is understood to mean a (meth)acrylate compound containing at least one alkylene group and having a molecular weight of 100 to 800 g / mol.

[0028] The term "(meth)acrylate(a) compound" includes: - (meth)acrylate compounds that do not contain alkylene oxide groups, and - (meth)acrylate compound (a1).

[0029] The methacrylate compound (a1) containing a low molecular weight alkylene group has the advantage of lower thermal stability at approximately 400°C compared to other (meth)acrylate compounds such as trimethylolpropane triacrylate. This lower stability allows the temporary protective layer to degrade at lower temperatures and more effectively during heat tempering. This lower thermal stability, compared to the presence of only "alkylene" groups, may be attributed to the presence of "alkylene-oxy" groups in the polymer matrix of the temporary protective layer.

[0030] The (meth)acrylate compound (a1) containing at least one alkylene group and having a molecular weight of 100 to 800 g / mol used according to the present invention has the following characteristics, alone or in combination: - These may account for at least 35% by mass, at least 40% by mass, at least 45% by mass, at least 50% by mass, at least 55% by mass, at least 60% by mass, at least 65% by mass, or at least 70% by mass of the total mass of the protective layer. - The (meth)acrylate compound (a1) is selected from (meth)acrylate compounds comprising: - One (meth)acrylate functional group, - Two (meth)acrylate functional groups, - Three (meth)acrylate functional groups, - Four (meth)acrylate functional groups, - Advantageously, the (meth)acrylate compound (a1) is selected from (meth)acrylate compounds comprising: - Two (meth)acrylate functional groups, - Three (meth)acrylate functional groups, - The (meth)acrylate compound (a1) comprises at least 35% by weight, at least 40% by weight, at least 45% by weight, at least 50% by weight, at least 55% by weight, at least 60% by weight, at least 65% by weight, or at least 70% by weight of the total weight of the protective layer. - A (meth)acrylate compound (a1) having three (meth)acrylate functional groups comprises at least 40%, at least 50%, at least 60%, or at least 70% by mass relative to the total mass of the organic protective layer. - (meth)acrylate compounds (a1) having alkylene groups are selected from: - (meth)acrylate compounds containing ethylene-oxy groups, - (meth)acrylate compounds containing propylene-oxy groups, - The (meth)acrylate compound (a1) is selected from (meth)acrylate compounds containing at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 alkyleneoxy groups. - The (meth)acrylate compound (a1) has an average molecular weight of 300 to 800 g / mol, 350 to 800 g / mol, or 350 to 500 g / mol. - Methacrylate compounds having alkylene oxide groups are selected from: - Polyethylene glycol diacrylate, such as: - Triethylene glycol diacrylate, - Tetra(ethylene glycol) diacrylate, - Polyethylene glycol (200) diacrylate, - Polyethylene glycol (300) diacrylate, - Polyethylene glycol (400) diacrylate, - Polyethylene glycol (600) diacrylate, - Hexanediol ethoxylated (5) diacrylate - Polypropylene glycol di(meth)acrylate, such as - Dipropylene glycol diacrylate, - Tripropylene glycol diacrylate, - Polypropylene glycol neopentyl glycol ether diacrylate, - 1,6-Hexanediol ethoxylated diacrylate - Polyethylene glycol tri(meth)acrylate, such as - Ethoxylated trimethylolpropane (3) triacrylate, - Ethoxylated trimethylolpropane (6) triacrylate, - Ethoxylated trimethylolpropane (9) triacrylate, - Polypropylene glycol tri(meth)acrylate, such as Polyethylene glycol (PEG) diacrylate has the formula: H₂C=CHCOO(CH₂CH₂)(OCH₂CH₂) n O2CCH=CH2, wherein n is 1 to 14, preferably 2 to 10, and more preferably 2 to 5. Their molecular weight is 200 to 800 g / mol. -1Especially 200, 300, 400, 500, 600, and 700. Particularly noteworthy are triethylene glycol diacrylate (n=2) and tetra(ethylene glycol) diacrylate (where (n=3)), polyethylene glycol (200) diacrylate, polyethylene glycol (300) diacrylate, polyethylene glycol (400) diacrylate, and polyethylene glycol (600) diacrylate. The average molar mass of PEG is usually indicated after the name, such as polyethylene glycol (200) or PEG-200 (200 g / mol).

[0031] Polypropylene glycol diacrylate corresponds to the following formula: H2C=CHCOO(C3H6)(OC3H6) n O2CCH=CH2, where n is 1 to 10, preferably 2 to 5. Particularly noteworthy are dipropylene glycol diacrylate, tripropylene glycol diacrylate, and polypropylene glycol neopentyl glycol ether diacrylate. Their molecular weights range from 200 to 800 g / mol. -1 Especially for 200, 300, 400, 500, 600 and 700.

[0032] Diethoxylated 1,6-hexanediol diacrylate has CAS number 84170-27-4.

[0033] Polypropylene glycol triacrylate contains three acrylate functional groups and at least one alkylene group. In particular, ethoxylated (3)trimethylolpropane triacrylate (TMPEOTA), ethoxylated (6)trimethylolpropane triacrylate and ethoxylated (9)trimethylolpropane triacrylate, which contain three alkylene groups, are mentioned.

[0034] The following list contains preferred alkylene oxide (meth)acrylate compounds (a1) and some of their trade names: - Polyethylene glycol (200) diacrylate (PEG200DA) SR259® - Tetraethylene glycol diacrylate (TTEGDA) SR268G® - Triethylene glycol diacrylate (TIEGDA) SR272® - Tripropylene glycol diacrylate (TPGDA) SR306® - Polyethylene glycol (400) diacrylate (PEG400DA) SR344® - Polyethylene glycol 600 diacrylate (PEG600DA) SR610® - Dipropylene glycol diacrylate (DPGDA). - Ethoxylated bisphenol A diacrylate (BPA3EODA) SR349®, SR508®, - Ethoxylated bisphenol A diacrylate (BPA4EODA) SR601E® - Ethoxylated 10-bisphenol A diacrylate (BPA10EODA) SR602® - Ethoxylated 3-trimethylolpropane triacrylate (TMP3EOTA) SR415® - Ethoxylated 6-trimethylolpropane triacrylate (TMP6EOTA) SR499® - Ethoxylated 9-trimethylolpropane triacrylate (TMP9EOTA) SR502® - Propoxylated 3-trimethylolpropane triacrylate (TMP3POTA) SR492® - Propoxylated 3-glyceryl triacrylate (GPTA) SR9020® - Preferably, ethoxylated glycerol triacrylates containing 1 to 11 ethyleneoxy groups. - Ethoxylated 12-glyceryl triacrylate (G12EOTA) SR9046® - Glyceryl propoxytriacrylate.

[0035] The polymerizable composition may contain (meth)acrylate compounds (a), some of which do not contain alkylene oxide groups.

[0036] The (meth)acrylate compound (a) used according to the present invention has the following characteristics, alone or in combination: - At least 50% by mass, at least 60% by mass, or at least 70% by mass of the total mass of the protective layer comprises a (meth)acrylate compound (a) with a molecular weight of 100 to 800 g / mol, preferably 100 to 500 g / mol, and / or - The composition comprises a (meth)acrylate compound (a) having 1 to 3 (meth)acrylate functional groups, and / or - The (meth)acrylate compound (a) having 1 to 3 (meth)acrylate functional groups, by mass, represents the following percentage of the total mass of the organic protective layer: - At least 50%, at least 60%, or at least 65%, and / or - up to 90%, up to 85%, up to 80%, up to 75%, and / or - The composition comprises a (meth)acrylate compound (a) having three (meth)acrylate functional groups, which, by mass, accounts for the following percentage of the total mass of the organic protective layer: - At least 40%, at least 50%, or at least 60%, and / or - up to 80%, up to 75%, up to 70%, or up to 65%, and / or - The composition comprises a (meth)acrylate compound (a) having one or two (meth)acrylate functional groups, which, by mass, accounts for the following percentage of the total mass of the organic protective layer: - At least 5%, and / or - up to 40%, up to 30%, up to 20%, or up to 10%, and / or - The composition comprises a (meth)acrylate compound (a) having at least four (meth)acrylate functional groups, which, by mass, accounts for the following percentage of the total mass of the organic protective layer: - At least 5%, at least 10%, or at least 15%, and / or - Up to 40%, up to 35%, up to 30%, up to 25%, or up to 20%, and / or - The compounds (a) and (b) that have reacted with each other account for at least 80%, at least 90%, at least 95%, and at least 98% of the organic protective layer in an increasing order of priority.

[0037] The list above includes (meth)acrylate compounds (a) that do not contain alkylene groups. These compounds can be used in limited proportions so as not to affect good degradation properties: - 1,6-Hexanediol diacrylate, - Tricyclodecanediethanol diacrylate (SR833S). - Decanediol diacrylate, - Diacrylate of ester glycol, - Trimethylolpropane triacrylate (TMPTA) SR351® - Pentaerythritol triacrylate (PETIA) SR444D® - Polybutadiene diacrylate, - Ethoxylated 15-trimethylolpropane triacrylate (TMP15EOTA) SR9035® - Trimethylolpropane triacrylate (TMPTA) SR351®.

[0038] The present invention also relates to materials that further comprise one or more of the following features: - The temporary organic protective layer has a weight loss of greater than 65%, preferably greater than 70%, or even greater than 75%, obtained by thermogravimetric analysis (TGA) at a heating rate of 10°C / min in air, from 30°C to 450°C, and / or - The temporary organic protective layer may also advantageously have a weight loss of more than 50%, preferably more than 60%, obtained by thermogravimetric analysis (TGA) from 30°C to 400°C at a heating rate of 10°C / min in air, and / or - The temporary organic protective layer may also advantageously have a weight loss of more than 25%, preferably more than 30%, or even more than 35% obtained by thermogravimetric analysis (TGA) in air at a heating rate of 10°C / min, from 30°C to 350°C, and / or - The organic protective layer has the following thickness: - Less than 50 μm, less than 30 μm, less than 20 μm, and / or - Greater than 1 µm, greater than 5 µm, greater than 10 µm, and / or - The temporary protective layer is in direct contact with the functional coating, and / or - The functional coating comprises a thin-layer stack comprising, starting from a substrate, alternating n functional metal layers based on silver or a silver-containing metal alloy and (n+1) dielectric coatings, each dielectric coating comprising at least one dielectric layer, such that each functional metal layer is disposed between two dielectric coatings, and / or - The functional coating is deposited by magnetron sputtering, and / or - The substrate with the functional coating has not undergone heat treatment at a temperature greater than 400°C.

[0039] According to an advantageous embodiment of the invention, the polymerizable composition has the following characteristics: - It contains at least one polymerization initiator, preferably a photoinitiator. - It may contain at least two different photoinitiators. - The polymerization initiator accounts for 0.1 to 20% by mass, or 2 to 15% by mass, preferably 5 to 15% by mass, and more preferably 8 to 12% by mass, relative to the total mass of the organic protective layer. - The (meth)acrylate compound a) is selected from monomers, oligomers, prepolymers, or polymers containing at least one (meth)acrylate functional group. - The (meth)acrylate compound a) is selected from esters of acrylic acid or methacrylic acid containing at least two (meth)acrylate functional groups. - The (meth)acrylate compound a) does not contain aromatic groups. - The (meth)acrylate compound a) comprises at least one oligomer or prepolymer monomer containing at least one, at least two, at least three, at least four, or at least five (meth)acrylate functional groups. - The polymerizable composition further comprises at least one additive selected from plasticizers, absorbents, separating agents, heat and / or light stabilizers, thickeners, or surface modifiers. - The total amount of all additives is 0 to 10% by mass relative to the total mass of the organic protective layer, preferably 0 to 5% by mass, or even 0.05 to 2.00% by mass.

[0040] According to the present invention, the polymerization initiator is not considered an additive.

[0041] The organic protective layer is continuous. It has the following thicknesses in an increasing order: - Less than 50 µm, less than 40 µm, less than 30 µm, less than 20 µm, and / or - Greater than 5 µm, greater than 7 µm, greater than 8 µm, greater than 10 µm.

[0042] The organic protective layer according to the invention is preferably applied at the exit of the production line used to manufacture a substrate with a functional coating. The step of depositing the organic protective layer can be easily integrated into the method for manufacturing a substrate with a functional coating.

[0043] Due to the sensible choice of (meth)acrylate compounds and optional solvents, the polymerizable composition exhibits a viscosity suitable for readily obtaining an organic protective layer with a thickness greater than or equal to 5 μm.

[0044] The chemical properties, degree of cross-linking, and density of the organic protective layer contribute to effective protection against wear, scratches, and corrosion.

[0045] The organic protective layer is preferably deposited and cross-linked by suitable means, which can be directly integrated at the exit of the functional coating deposition chamber. This allows for the prevention of any contamination of the coated substrate and enables the continuous production of protected materials.

[0046] The polymerizable composition can be applied at ambient temperature by any known means, and in particular by roller coating, spraying, dip coating, curtain coating or spray gun application.

[0047] This water-insoluble organic protective layer provides effective protection even during the washing process.

[0048] Although the present invention is particularly well-suited for protecting substrates with mechanically weak functional coatings, the solutions of the present invention can be applied to protect substrates with any type of functional coating.

[0049] The functional coating comprises at least one functional layer. The functional layer is preferably a layer that can react to solar radiation and / or long-wavelength infrared radiation. These functional layers are, for example, silver-based or silver-containing metal alloy-based metallic functional layers. They are deposited between dielectric coatings, which typically comprise multiple dielectric layers, allowing for the tuning of the optical properties of the stack. Furthermore, these dielectric layers enable protection of the silver layer from chemical or mechanical corrosion.

[0050] The functional coating thus advantageously comprises at least one silver-based functional metal layer and at least two dielectric coatings, each dielectric coating comprising at least one dielectric layer, such that each functional metal layer is disposed between the two dielectric coatings.

[0051] The substrate may comprise a functional coating comprising a thin stack consisting of alternating n functional metal layers based on silver or a silver-containing metal alloy and (n+1) dielectric coatings, each dielectric coating comprising at least one dielectric layer, such that each functional metal layer is disposed between two dielectric coatings. Preferably, n is equal to 1, 2, 3, or 4. Even more preferably, n is greater than 1, particularly n is equal to 2 or 3.

[0052] The substrate may sequentially comprise two alternating functional metal layers (especially functional layers based on silver or on a silver-containing metal alloy) and three dielectric coatings, each dielectric coating comprising at least one dielectric layer, such that each functional metal layer is disposed between two dielectric coatings.

[0053] The substrate may further include a functional coating comprising a thin-layer stack comprising, starting from the substrate, three alternating functional metal layers based on silver or a silver-containing metal alloy and four dielectric coatings, each dielectric coating comprising at least one dielectric layer such that each functional metal layer is disposed between two dielectric coatings.

[0054] The thickness of the functional coating is: - Greater than 50 nm, greater than 100 nm, preferably greater than 150 nm, and / or - Less than 350 nm, or less than 300 nm.

[0055] According to a particularly advantageous embodiment of the invention, the functional coating comprises an organic protective upper layer selected from titanium and / or zirconium nitrides, oxides, or oxynitrides. The upper layer of the functional coating is the layer furthest from the substrate and / or the layer in direct contact with the organic protective layer.

[0056] The thickness of these upper layers is preferably 1 to 20 nm and even more preferably 1 to 5 nm.

[0057] The top layer of the functional coating, especially when it is based on titanium oxide, is important because it promotes adhesion between the inorganic layer and the organic protective layer of the functional coating.

[0058] The functional coating can be deposited by any known means, such as by magnetron sputtering, thermal evaporation, CVD or PECVD, pyrolysis, chemical deposition, sol-gel deposition of inorganic layers, or wet deposition.

[0059] The functional coating is preferably deposited by magnetron sputtering. According to this advantageous embodiment, all layers of the functional coating are deposited by magnetron sputtering. The organic protective layer is advantageously in direct contact with the functional coating.

[0060] The substrate is preferably a glass substrate. The glass substrate may be flat or curved, colorless and / or colored. The thickness of the substrate is preferably 1 to 19 mm, more particularly 2 to 12 mm, or even 3 to 12 mm.

[0061] The organic protective layer can be deposited: - On each main surface of the substrate, and / or - On at least one edge of the substrate, and / or - On each edge of the substrate.

[0062] The present invention also relates to a method for obtaining materials according to the invention. The method of the present invention includes one or more of the following features: The functional coating is deposited by magnetron sputtering, and the organic protective layer is in direct contact with the functional coating. - Apply the polymerizable composition to the functional coating. - The organic protective layer is obtained through UV crosslinking.

[0063] Preferably, the functional coating is deposited by magnetron sputtering, and the organic protective layer is in direct contact with the functional coating.

[0064] The organic protective layer can be formed immediately after the step of depositing the functional coating. According to the invention, when the organic protective layer can be formed in less than 10 minutes, preferably less than 5 minutes, and even more preferably less than 1 minute after the step of depositing the functional coating, the organic protective layer is considered to be formed "immediately after".

[0065] The present invention also relates to assembled glass comprising materials according to the invention. The assembled glass can be installed on a vehicle or building.

[0066] The assembled glass according to the invention is particularly suitable for buildings or vehicles, especially as side windows, retractable roofs, or rear windows. It is also suitable for use as refrigerator doors or windows with anti-fogging (anti-condensation) functions, especially for display cases of frozen products in supermarkets.

[0067] The following examples illustrate the present invention. Example

[0068] I. Substrates and Functional Coatings The functional coating defined below is deposited on a substrate made of transparent soda-lime glass with a thickness of 6 mm.

[0069] The functional coating is deposited using a magnetron sputtering apparatus. The deposition conditions for the layers deposited by sputtering (so-called "magnetron cathode" sputtering) are summarized in Table 1 below. at.: atom; wt: weight; At 550 nm.

[0070] The materials and physical thicknesses (in nanometers, unless otherwise stated) of each layer or coating that makes up the stack are listed in the table below according to their position relative to the substrate on which the stack is attached.

[0071] II. Organic protective layer 1. raw materials Prepare polymerizable compositions. These compositions contain (meth)acrylate compounds, polymerization initiators, and optional additives. Mix the various components and additives by mechanical stirring.

[0072] a) (Meth)acrylate monomers and oligomers These (meth)acrylate compounds comprise oligomers and monomers containing at least one acrylate functional group. The following compounds, sold by Sartomer, are used: A – Isoborneol acrylate monofunctional acrylate monomer with a molecular weight of 208.30 g / mol ((meth)acrylate (a) compound). B1 - Tricyclodecanediethanol diacrylate (SR833S), a difunctional acrylate monomer with a molecular weight of 304 g / mol ((meth)acrylate (a) compound). B2 - Dipropylene glycol diacrylate, a difunctional acrylate monomer with a molecular weight of 242.3 g / mol ((meth)acrylate (a1) compound). C1-Trimethylolpropaneethoxytriacrylate, a trifunctional acrylate monomer with a molecular weight of 428 g / mol ((meth)acrylate (a1) compound) C2-Trimethylolpropane triacrylate (SR351), a trifunctional acrylate monomer with a molecular weight of 296 g / mol ((meth)acrylate(a)compound) D-Tetrafunctional aliphatic urethane acrylate oligomer CN9276 (hereinafter referred to as tetrafunctional acrylate oligomer), wherein the molecular weight is 1,000 g / mol ((meth)acrylate (a) compound) E-dipentaerythritol pentaacrylate, a pentafunctional acrylate monomer with a molecular weight of 524.5 g / mol ((meth)acrylate (a) compound).

[0073] b) Photoinitiator The initiator may be selected from photoinitiators sold by BASF under the name Irgacure® (such as Iragure 500), by Lambson under the names Speedcure 500 and Speedcure 84, or by Lamberti under the name Esacure HB. The photoinitiator may also be 1-hydroxy-1-methylethylphenyl ketone.

[0074] c) Additives Adhesion promoters can be used.

[0075] 2. Polymerizable compositions The test compositions are specified in the table below in parts by weight.

[0076] The polymerizable compositions are liquids. They are filtered at 0.2 µm to avoid aggregates. Their dry extracts can be adjusted by adding solvents to achieve the desired protective layer thickness.

[0077] The composition is defined as a percentage by mass.

[0078] The composition is applied to a glass substrate by spin coating or by using a Meyer bar.

[0079] The coating cured by UV radiation is cross-linked at a rate of 10 to 50 m / min by UV radiation provided by a LightHammer® lamp with an H+ bulb.

[0080] The polymerizable composition is applied to achieve a cured thickness of approximately 15 μm.

[0081] 3. Preparation of test materials The table below lists each material that includes a substrate coated with a functional coating: - Properties of organic protective layers - The polymerizable composition used, - The thickness of the organic protective layer after curing.

[0082] III. Characterization 1. Evaluate the removal achieved through heat treatment 1.a. Thermogravimetric analysis The thermal stability of the protective coating was determined by thermogravimetric analysis (TGA) at atmospheric pressure in air at a heating rate of 10 °C / min at temperatures ranging from 30 °C to 700 °C.

[0083] [ Figure 1 The curves showing the mass loss as a function of temperature after curing (in percentage) are displayed: - Comparative (comp.) composition (CC). - The composition (CI1) according to the invention.

[0084] The graph shows the shift towards lower temperatures in the CI1 curve. The composition according to the invention begins to degrade at significantly lower temperatures. Due to its lower thermal stability, the composition degrades even more rapidly in a tempering furnace.

[0085] Tempering tests were conducted using a vertical furnace. The vertical furnace allows for the simulation of tempering conditions in a laboratory setting. The glass is vertically secured to a mobile support using a clamping system. This support automatically inserts itself into the furnace at a temperature higher than the desired temperature. Once the tempering time is complete, the support is lowered, and a nozzle system exposes the glass to jets of cold air on both sides. The furnace has no convection and the temperature is regulated using three thermocouples located in three different positions. The following parameters were set: - Furnace temperature: 670℃ - Heating time: Variable - Cooldown time: 100 s - Cold air pressure: 0.7 bar.

[0086] For each material, determine the shortest tempering time. These times correspond to the following minimum times: - Obtain high-quality assembled glass, especially glass that is free from cracks, iridescence, corrosion of functional coatings, and has good flatness. - To obtain assembled glass with satisfactory fragmentation, and - Remove the temporary protective layer.

[0087] Using existing polymerizable compositions (CC), the minimum tempering time under our conditions is 330 s. When these times are shortened, unburned composition is still observed on the functional coating.

[0088] Using the polymerizable composition (CI1) of the present invention, no residue and good fragmentation on breaking were observed for tempering times of 315 s or even shorter.

[0089] 2. Odor assessment after heat treatment During the heat treatment of the temporary protective layer in the prior art, volatile organic compounds (“VOCs”) may be emitted, and under certain conditions: - During edge finishing: The grinding wheel removes the protective and functional coatings from the substrate, and / or - During high-temperature heat treatment.

[0090] The emission of these volatile compounds is likely to produce unpleasant odors.

[0091] These negative effects were not observed with the materials Inv.1 and Inv.2 according to the invention. This is likely due to the absence of high molecular weight compounds (i.e., approximately 1000 g / mol).

Claims

1. A material comprising a substrate coated with a functional coating and a temporary organic protective layer deposited on at least a portion of the functional coating, the protective layer being obtained by a crosslinkable polymerizable composition comprising (a) a (meth)acrylate compound and (b) optionally a polymerization initiator, characterized in that: The temporary organic protective layer has a weight loss of more than 65%, preferably more than 70%, or even more than 75% obtained by thermogravimetric analysis (TGA) at a heating rate of 10°C / min in air, from 30°C to 450°C.

2. A material comprising a substrate coated with a functional coating and a temporary organic protective layer deposited on at least a portion of the functional coating, the protective layer comprising a polymer matrix obtained by a crosslinking polymerizable composition comprising (a) a (meth)acrylate compound and optionally (b) a polymerization initiator, characterized in that... The polymerizable composition comprises a (meth)acrylate compound (a1) containing at least one alkylene group and having a molecular weight of 100 to 800 g / mol, and the (meth)acrylate compound (a1) accounts for at least 30% of the total mass of the protective layer.

3. The material according to any one of the preceding claims, characterized in that... The total mass percentage of the protective layer comprises at least 70% by mass of a (meth)acrylate compound (a) with a molecular weight of 100 to 800 g / mol, preferably 100 to 500 g / mol.

4. The material according to any one of the preceding claims, characterized in that... The polymerizable composition comprises at least 50% by mass of a (meth)acrylate compound (a1) of the total mass of the protective layer.

5. The material according to the preceding claims, characterized in that... The (meth)acrylate compound (a1) contains 1 to 3 (meth)acrylate functional groups.

6. The material according to any one of the preceding claims, characterized in that... The (meth)acrylate compound (a1) is selected from (meth)acrylate compounds containing at least two alkylene oxide groups.

7. The material according to any one of the preceding claims, characterized in that... The (meth)acrylate compound (a1) has an average molecular weight of 300 to 800 g / mol.

8. The material according to any one of the preceding claims, characterized in that... The (meth)acrylate compound (a1) having three (meth)acrylate functional groups accounts for at least 40% of the total mass of the organic protective layer.

9. The material according to any one of the preceding claims, characterized in that... Compounds (a) and (b) that have reacted with each other account for at least 90% of the mass of the organic protective layer.

10. The material according to any one of the preceding claims, characterized in that... The polymerizable composition comprises a (meth)acrylate compound (a) having 1 to 3 (meth)acrylate functional groups, which accounts for at least 50% by mass relative to the total mass of the organic protective layer.

11. The material according to any one of the preceding claims, characterized in that... The polymerizable composition comprises a (meth)acrylate compound (a) having one or two (meth)acrylate functional groups, which accounts for at least 5% by mass relative to the total mass of the organic protective layer.

12. The material according to any one of the preceding claims, characterized in that... The polymerizable composition comprises a (meth)acrylate compound (a) having at least four (meth)acrylate functional groups, which accounts for at least 5% by mass relative to the total mass of the organic protective layer.

13. The material according to any one of the preceding claims, characterized in that... The organic protective layer has the following thickness: - Less than 50 µm, and - Greater than 1 µm.

14. The material according to any one of the preceding claims, characterized in that... The temporary protective layer is in direct contact with the functional coating.

15. The material comprising a substrate according to any one of the preceding claims, characterized in that... The functional coating is deposited by magnetron sputtering.

16. The material according to any one of the preceding claims, characterized in that... The functional coating comprises at least one functional silver-based metallic layer.

17. The material comprising a substrate according to any one of the preceding claims, characterized in that... The functional coating comprises a thin-layer stack, which sequentially comprises, starting from the substrate, n alternating functional metal layers based on silver or based on a silver-containing metal alloy and (n+1) dielectric coatings, each dielectric coating comprising at least one dielectric layer, such that each functional metal layer is disposed between two dielectric coatings.

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