Glazing comprising a solar control layer and a protective coating comprising yttrium oxide and at least one element selected from hafnium and / or titanium

Abstract

Article with antisolar properties comprising a glass substrate, a stack of layers deposited on said substrate, said stack comprising at least one functional layer absorbing and / or reflecting a portion of solar radiation and a coating layer of said stack, wherein said coating layer is a dielectric oxide layer comprising yttrium, and at least one element selected from hafnium and titanium.

Description

Title of the invention: Glazing comprising an anti-solar stack and a protective coating comprising yttrium oxide and at least one element selected from hafnium and / or titanium.

[0001] The present invention relates to an article with anti-solar properties comprising a stack of layers giving it anti-solar properties and a protective coating to ensure mechanical resistance, in particular scratch resistance and chemical resistance, in particular hydrolytic resistance and in particular resistance to acidic environments.

[0002] The invention relates to insulating glazing, also known as solar control glazing, composed of stacks of thin films, at least one of which is functional, meaning that it acts on solar radiation primarily by reflecting and / or absorbing at least a portion of the solar radiation. The application most specifically targeted by the invention is primarily in the building sector, as solar control glazing. Without departing from the scope of the invention, this glazing can also be used as vehicle glazing, such as side windows, car roofs, and rear windows.

[0003] For the purposes of this application, a "functional" or "active" layer is defined as the layers of the stack that provide the stack with most of its thermal insulation properties. Most often, the thin-film stacks used in glazing provide significantly improved insulation properties primarily, if not exclusively, due to the intrinsic properties of these active layers. These layers act on the radiation flux, particularly infrared radiation, passing through the glazing, unlike other layers, which are generally made of dielectric material and whose main function is usually to provide chemical or mechanical protection to the functional layers.

[0004] As previously stated, such glazing units with stacks incorporating functional thin films act on incident solar radiation either by absorbing a portion of said incident radiation by the functional layer(s), or by reflecting it back through these same layers. The reflection may be directed towards a portion of the solar spectrum, for example in the infrared and / or visible range. Most often, these layers act on incident solar radiation by both reflection and absorption.

[0005] For the purposes of this invention, "anti-solar" means the ability of glazing to limit the energy flux, in particular, but not exclusively, solar infrared (1RS) radiation, passing through it from the outside to the inside of the building. In other applications, such as automobiles, it may also be desirable to limiting the amount of heat entering the vehicle's interior, that is to say, limiting the energy transmission of solar radiation through the glazing, which can be a roof, a rear window or side windows.

[0006] Coatings are conventionally deposited using magnetic field-assisted vacuum sputtering techniques, where a cathode of the material or a precursor of the material to be deposited is used. This technique is commonly used today, particularly when the coating to be deposited consists of a more complex stack of successive layers with thicknesses ranging from a few nanometers to a few tens of nanometers.

[0007] The most efficient stacks currently commercially available for solving the aforementioned problems, and deposited using magnetron sputtering techniques, incorporate a silver-based metallic layer that functions primarily by reflecting a large portion of the incident IR (infrared) radiation. These stacks are thus mainly used as low-emissivity (or low-e) glazing for the thermal insulation of buildings. They can also be used as anti-insulation due to their ability to reflect the infrared portion of solar radiation. However, these layers are very sensitive to humidity and are therefore used exclusively in double glazing, on surface 2 or 3, to protect them from moisture. The stacks according to the invention do not include such layers based on silver, gold, platinum, copper, or even nickel.More generally, the articles according to the invention do not contain such metals, or only in very negligible quantities, particularly in the form of unavoidable impurities.

[0008] Other glazing incorporating stacks comprising layers with anti-solar function have also been reported in the field, this time based on functional layers based on niobium, possibly partially or totally nitrided, as described for example in applications WO01 / 21540, WO2009 / 112759 or WO2009 / 150343, to which reference will be made for further details.

[0009] More recently, stacks with a titanium nitride-based functional layer have also been proposed. Reference may be made, for example, to applications WO2018 / 129135 or WO2019 / 002737.

[0010] The functional layers based on niobium, niobium nitride, or titanium nitride mentioned above make it possible to both reflect and absorb a significant portion of the infrared radiation from solar radiation without making the glazing opaque, when their thickness is limited to values ​​less than 50 nm, in particular less than 40 nm or even less than 30 nm. Such a property confers solar protection properties to the stack in which it is included, as well as to the glazing coated with such a stack.

[0011] According to another known embodiment, the functional layer is a layer comprising titanium oxide. Such embodiments are described in particular in publications EP1919838, EP3122694 or WO2020 / 002845.

[0012] According to another known embodiment, the functional layer is a layer comprising a chromium-nickel alloy, the alloy optionally being nitrided. Such embodiments are described in particular in publications WO2012 / 096771, EP779255 and EP747329.

[0013] The present invention relates to such stacks and glass articles.

[0014] In such articles, resistance to scratches and wear is a question of importance. Uncoated soda-lime glass, for example, is well known for its poor scratch resistance. The various coatings applied to the glazing, for example those used to provide specific functionalities, must also be protected from scratches and wear.

[0015] Improving the scratch resistance of functionalized glazing is generally achieved by applying a protective coating layer. This protective layer, also called an "overcoat," is typically a few nanometers to a few tens of nanometers thick. It can be deposited onto the functional stack using conventional thin-film deposition processes, such as the sputtering process already mentioned, particularly when enhanced by a magnetic field, in which case it is called the "magnetron" process.

[0016] Diamond-like carbon (DLC) coatings, for example, are already described as increasing the scratch resistance of glazing. However, the main drawback of DLC is its inherent thermal instability. For this reason, DLC coatings are not suitable in themselves for applications requiring exposure to high temperatures, such as annealing, tempering, or bending. Additional sacrificial layers must be provided to protect the DLC coating during heat treatments (WO 2005 / 021454, WO 2019 / 020485), which makes their use cumbersome.

[0017] External layers based on transition metal oxides, such as zirconium oxide-based layers or titanium and zirconium oxide-based layers, have also been used as protective layers (WO 2016 / 097557). These overlayers can withstand heat treatments and moderately improve the scratch resistance of glazing systems, but they generally do not achieve the scratch-resistant performance of DLC coatings.

[0018] Publication WO2021 / 063921 describes a 5 nm yttrium oxide outer protective layer deposited over the stack. This layer exhibits a It has very good mechanical resistance, but its hydrolytic resistance can still be improved.

[0019] Patent application EP2314451 describes an external protective layer made of YZrOx.

[0020] It is therefore always necessary to have a protective coating capable of improving wear and corrosion resistance to a level substantially equivalent to or approaching that of DLC coatings, while also being able to withstand heat treatments. The applicant has found that dielectric protective layers based on a compound containing yttrium, and in particular based on yttrium oxide and another element selected from titanium or hafnium, in addition to meeting these requirements, also offer good transparency, which is particularly advantageous for protecting stacked layers of glazing.

[0021] Consequently, the present invention relates to an article with anti-solar properties comprising:

[0022] - a glass substrate,

[0023] - a stack of layers deposited on said substrate,

[0024] - said stack comprising at least one functional absorbing and / or re bending a portion of the solar radiation and

[0025] - a coating layer of said stack,

[0026] wherein said coating layer is an oxide layer comprising yttrium, and at least one element selected from hafnium and titanium.

[0027] The coating layer therefore consists of a dielectric oxide layer comprising yttrium (Y) and at least one element selected from titanium (Ti) or hafnium (Hf). For the purposes of the present invention, said elements (Y and Hf and / or Ti) are therefore present in the layer other than as unavoidable impurities.

[0028] In contrast to the functional layers also present in the present stacks, the term "dielectric layer" refers, for example, to a layer that does not exhibit metallic characteristics. This term specifically designates a layer made of a material having an n / k ratio (n = refractive index; k = extinction coefficient) over the entire visible range (from 380 nm to 780 nm) that is equal to or greater than 5. Such materials, in their bulk form and free from impurities, thus exhibit high resistivity, in particular a resistivity greater than 10¹⁰ ohm-meters (Ωm) at 25°C.

[0029] According to other advantageous embodiments of the present invention, which may optionally be combined with each other: - Said coating layer comprising at least 10 atomic percent of yttrium, based on the total yttrium, titanium and hafnium atoms present in said layer, preferably between 20 and 55 atomic percent of yttrium or even between 33% and 49% yttrium based on all the yttrium, titanium and hafnium atoms present in said layer. The coating layer comprises at least 25 atomic percent of at least one element selected from hafnium and titanium, based on the total number of yttrium, titanium and hafnium atoms present in said layer, preferably more than 50 atomic percent of at least one element selected from hafnium and titanium, in particular between 51 and 90 atomic percent of at least one element selected from hafnium and titanium, based on the total number of yttrium, titanium and hafnium atoms present in said layer. The atomic ratio (Hf+Ti) / Y in said coating layer is greater than 1. The functional layer comprises a material selected from metallic niobium, niobium nitride, titanium nitride or titanium oxide, ITO (indium tin oxide), a layer comprising chromium, in particular a nickel-chromium alloy possibly nitrided (often referred to as NiCr or NiCrN in the technical field) or a layer consisting essentially of chromium. The coating layer comprises less than 5 atomic percent zirconium, preferably less than 1 atomic percent zirconium, based on the total number of yttrium, titanium, zirconium and hafnium atoms present in said layer, and preferably is still free of zirconium. The coating layer is an yttrium and titanium oxide (with inevitable impurities). The coating layer is an oxide of yttrium and hafnium (with inevitable impurities). The coating layer is an oxide of yttrium, titanium and hafnium (with inevitable impurities). The coating layer has a thickness of between 1 and 100 nm, preferably between 1 and 20 nm and most preferably between 2 and 10 nm, or even between 3 and 8 nm. The coating layer constitutes the outermost layer of the succession of layers covering the glass surface. The functional layer(s) each have a physical thickness of between 2 and 50 nm, preferably between 5 and 30 nm. The stack includes, above and / or below the functional layer(s), silicon nitride-based layers, preferably having a physical thickness of between 1 and 100 nm, preferably again between 5 and 50 nm. - The stack consists solely of the functional layer(s) and dielectric layers, said dielectric layers being preferably chosen from oxides of silicon, titanium, zirconium or their mixtures, tin or nitrides of silicon, aluminum or a mixture of silicon and aluminum. - The functional stack comprises or is constituted by the succession of at least the following layers, starting from the surface of the glass substrate:

[0030] - a sub-layer comprising silicon nitride, preferably of thickness between 1 nm and 100 nm,

[0031] - a functional layer preferably of physical thickness between 2 and 50 nm, preferably between 5 and 30 nm, the functional layer comprising a material selected from metallic niobium, niobium nitride, titanium nitride or titanium oxide, an alloy of at least the elements Ni and Cr, optionally nitrided,

[0032] - an overlayer comprising silicon nitride, preferably of thickness between 1 nm and 100 nm,

[0033] - possibly a protective layer against scratches, preferably chosen among Ti and / or Zr oxides, preferably with a thickness between 1 nm and 10 nm. - The stack does not include layers based on silver, gold, platinum or copper. - The said article is soaked.

[0034] The coating layer as described above may, according to another embodiment, optionally include another minor element other than O, Y, Hf, and Ti, generally in a proportion of between 0.5 and 10% of all the elements present in the layer other than oxygen, for example, in an amount of between 1 and 5% of all the elements present in the layer other than oxygen. The dopant may, in particular, be chosen from among the transition metals and the lanthanides.

[0035] In a particular embodiment however, the coating layer is free of zirconium, or comprises a negligible amount of zirconium, such as less than 1 atomic% zirconium.

[0036] According to the invention, oxygen preferably represents more than 50% atomic, or even more than 60% atomic, of the atoms present in the coating layer.

[0037] The yttrium oxide-based dielectric layer typically has a refractive index, measured at 550 nm, of between 1.7 and 2.3, in particular from 1.8 to 2.2.

[0038] According to the invention, when the functional layer(s) comprise metallic niobium or niobium nitride, it / they may comprise more than 50% atomic niobium based on the elements present in said layer (other than nitrogen for niobium nitride), or even more than 75% atomic niobium and preferably more than 80%, or even more than 90% niobium, based on the elements present in said layer (other than nitrogen for niobium nitride). According to a particular embodiment of the invention, the layer(s) based on metallic niobium or on niobium nitride comprise only the element niobium, apart from unavoidable impurities (other than nitrogen for niobium nitride).

[0039] Without departing from the scope of the invention, however, other elements such as zirconium in particular, may also be present in such layers, preferably in a minority quantity compared to niobium, for example in a proportion of between 1 and 30% of the niobium atoms present in the layer, or in a proportion of between 5 and 20% of the niobium atoms present in the layer.

[0040] According to the invention, the layer(s) based on metallic niobium or niobium nitride are in principle oxygen-free, although oxygen may be present as unavoidable impurities in the layer, particularly following quenching, but in a proportion much lower than that of the niobium and nitrogen that may be present. For example, the O / Nb atomic ratio in the functional layers according to the invention is less than 0.1, or even less than 0.05.

[0041] According to another possible embodiment of the present invention, the functional layer(s) advantageously comprise titanium nitride.

[0042] Titanium-based coatings according to the invention comprise, for example, more than 50% by weight of titanium nitride, preferably more than 80% or even more than 90% by weight of titanium nitride. Preferably, such coatings are essentially composed of titanium nitride.

[0043] The titanium nitride according to the invention is not necessarily stoichiometric (Ti / N atomic ratio of 1) but may be over- or under-stoichiometric. Advantageously, the N / Ti ratio is between 1 and 1.2, preferably greater than 1. Also, the titanium nitride according to the invention may comprise a minor amount of oxygen, for example between 1 and 10 mol% oxygen, in particular between 1 and 5 mol% oxygen.

[0044] According to one possible mode, the titanium nitride layers according to the invention can for example correspond to the general formula TiNxOy, in which 1.00 < x < 1.20 and in which 0.01 < y < 0.10.

[0045] According to another possible embodiment of the present invention, the functional layer(s) advantageously comprise titanium oxide. Without departing from the scope of the invention, however, other elements, preferably silicon or zirconium in particular, may also be present in such layers, but in a minor quantity compared to titanium, for example according to a a proportion of between 1 and 30% of the titanium atoms present in the layer, or a proportion of between 5 and 20% of the titanium atoms present in the layer.

[0046] According to another possible embodiment of the present invention, the functional layer(s) advantageously and preferably comprise essentially an alloy of at least nickel and chromium or an alloy of nickel and chromium, said alloy being optionally nitrided, as described in publications WO2012 / 096771, EP779255 or EP747329.

[0047] The invention also relates to a method for manufacturing a coated article as defined above, said method comprising the provision of a glass substrate, the deposition of a stack of layers on said substrate; said stack comprising at least one functional layer as described above, and the deposition of a coating layer on top of said stack, wherein the coating layer is as described above.

[0048] Finally, the invention relates to a monolithic building glazing, comprising an article as previously described.

[0049] The substrate is preferably, according to the invention, a sheet of glass. It is preferably transparent, colorless (in which case it is clear or extra-clear glass) or colored, for example blue, green, gray, or bronze. The thickness of the substrate generally varies between 0.1 mm and 19 mm, preferably between 0.5 and 9 mm, in particular between 2 and 8 mm, and even between 4 and 6 mm. The substrate may be flat or curved.

[0050] The glass is preferably of the soda-lime silicate type, but it may also be of the borosilicate or aluminoborosilicate type. The glass substrate is preferably of the float glass type, that is to say, likely to have been obtained by a process that consists of pouring molten glass onto a bath of molten tin (float bath). The glass substrate may also be obtained by rolling between two rollers, a technique which notably allows for imprinting patterns on the surface of the glass. The glass substrate may be tempered glass.

[0051] By "clear glass" is meant soda-lime-silica glass obtained by the float process which, when uncoated, has a light transmission of approximately 90%, a light reflection of approximately 8%, and an energy transmission of approximately 87%, for a thickness of 4 mm. Light and energy transmission and reflection values ​​are defined by standard NF EN 410. Typical clear glass is sold, for example, under the name SGG PlaniClear by Saint-Gobain Glass France or under the name Planibel Clair by AGC Fiat Glass Europe. These substrates are traditionally used in the manufacture of low-emissivity glazing.

[0052] In the context of the present invention, the terms "below" and "above", Descriptions associated with the position of two elements A and B (for example, a layer, but also a coating or a substrate) do not preclude the presence of other elements between said elements A and B. In particular, when they relate to the position of one layer relative to another, this means that the first layer is closer to the substrate than the other. Conversely, an element A "in direct contact" with an element B means that no other element is positioned between them. The same applies to the expressions "directly on" and "directly under." It is therefore understood that, unless otherwise specified, other layers may be inserted between each of them.

[0053] Similarly, the terms "underlayer" and "overlayer" refer to the relative position of one layer in relation to another in the stack, with the surface of the glass substrate being taken as a reference.

[0054] The coating layer generally has a thickness of between 1 and 50 nm, preferably between 2 and 20 nm, and preferably between 3 and 8 nm. A functional stacking occurs between the substrate and the coating layer. In all cases, the coating layer is advantageously the outermost layer, i.e., the layer in direct contact with the atmosphere, as disposed on the substrate.

[0055] The coating layer can be deposited on the substrate by sputtering, in particular by the magnetic field-assisted sputtering process (the "magnetron" process). All layers, including those of the functional stack and the protective coating layer, are advantageously deposited by sputtering, in particular within the same deposition unit.

[0056] The coating layer according to the present invention can withstand heat treatment. The process of the present invention may therefore include a heat treatment step after the coating layer has been deposited. The heat treatment step may be a quenching step to strengthen the substrate, particularly in the case of a glass substrate. The quenching step is generally carried out at temperatures of 550 to 750°C for a few minutes, for example, 3 to 30 minutes, followed by rapid cooling.

[0057] The present invention therefore also relates to glazing comprising a coated article as described above. The glazing may preferably be single-pane (monolithic), but also multi-pane (in particular double or triple), that is to say, made up of several sheets of glass creating a gas-filled space, curved and / or laminated glazing. The glazing may also be tempered and / or reinforced. The coating layer according to the present invention is generally positioned on the outer faces of the glazing (either inwards and / or outwards).

[0058] The present invention and its advantages are illustrated by the following non-limiting examples. Example 1 (comparative):

[0059] A first stack of reference layers whose structure is given in Table 1 below is deposited on a Planiclear® glass substrate by magnetron sputtering according to well-known techniques, for example as described in the publications previously cited. Example 2 (comparative):

[0060] A second stack of layers identical to the first is deposited on a Planiclear® glass substrate but an external protective layer of TiZrOx of 5 nm is deposited on top of the stack, in accordance with the teaching of application WO 2016 / 097557. Example 3 (comparative):

[0061] A third stack of layers identical to the first is deposited on a Planiclear® glass substrate but an external DLC protective layer of 10 nm is deposited on top of the stack, in accordance with the teaching of application WO 2005 / 021454. Example 4 (comparative):

[0062] A fourth layer stack identical to the first is deposited on a Planiclear® glass substrate, but an external 5 nm yttrium oxide protective layer is deposited above the stack. This layer is deposited by magnetron sputtering using a 210 mm x 90 mm yttrium flat metal target with a power of 500 W and under a pressure of 2 pbar in an atmosphere with an Ar / O2 ratio of 10 / 4, with a flow rate of 28 sccm in accordance with publication WO2021 / 063921. Example 5 (comparative):

[0063] A fifth stack of layers identical to the first is deposited on a Planiclear® glass substrate but an external protective layer of 5 nm YZrOx is deposited on top of the stack, in accordance with the teaching of application EP2314451. Example 6 (according to the invention):

[0064] A sixth stack of layers identical to the first is deposited on a Planiclear® glass substrate but an external protective layer of YTiOx of 5 nm is deposited on top of the stack, in accordance with the teaching of the present invention.

[0065] This layer is deposited by magnetron co-spraying using in the same compartment two flat metallic targets, one made of metallic yttrium and the other of metallic titanium, with a power of 500W on the two targets and under a pressure of 2 pbar in an atmosphere having an Ar / O2 ratio of 10 / 4, with a flow rate of 28 sccm.

[0066] The analysis by Castaing microprobe (or electron probe microanalyzer EPMA) of the material deposited by sputtering is given below in atomic percentage:

[0067] Ti: 19%, Y: 17.5%, O: 63.5%.

[0068] The coating layer therefore comprises 52% atomic titanium and 48% atomic yttrium, based on the total number of yttrium and titanium atoms present in said layer. Example 7 (according to the invention):

[0069] A seventh stack of layers identical to the first is deposited on a Planiclear® glass substrate but an external protective layer of YHfOx of 5 nm is deposited on top of the stack, in accordance with the teaching of the present invention.

[0070] This layer is deposited by magnetron co-spraying using in the same compartment two flat metallic targets, one made of metallic yttrium and the other of metallic hafnium, with a power of 500 W for the two targets and under a pressure of 2 pbar in an atmosphere having an Ar / O2 ratio of 10 / 4, with a flow rate of 28 sccm.

[0071] The analysis of the Castaing microprobe material deposited by sputtering is given below:

[0072] Hf: 20%, Y: 16%, O: 64%.

[0073] The coating layer therefore comprises 55% atomic hafnium and 45% atomic yttrium, based on the total number of yttrium and hafnium atoms present in said layer. Example 8 (according to the invention):

[0074] An eighth stack of layers identical to the first is deposited on a Planiclear® glass substrate but an external protective layer of YHfOx of 5 nm of a different composition than the preceding example 7 is deposited on top of the stack, in accordance with the teaching of the present invention.

[0075] This layer is deposited by magnetron co-spraying using in the same compartment two flat metallic targets, one made of metallic yttrium and the other of metallic hafnium, with a power of 500W on the hafnium target and 200W on the yttrium target, under a pressure of 2 pbar in an atmosphere having an Ar / O2 ratio of 10 / 4, with a flow rate of 28 sccm.

[0076] The analysis of the Castaing microprobe material deposited by sputtering is given below:

[0077] Hf: 28%, Y: 10%, O: 62%.

[0078] The coating layer therefore comprises 74% atomic hafnium and 26% atomic of yttrium, based on the set of yttrium and hafnium atoms present in said layer.

[0079] Table 1 below shows the different compositions and thicknesses of the layers constituting the stacks tested from the surface of the glass substrate.

[0080] [Tables 1] Ex.l Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7 Ex. 8 Glass Glass Glass Glass Glass Glass Glass Glass Glass Si3N4 Si3N4 Si3N4 Si3N4 Si3N4 Si3N4 Si3N4 Si3N4 (10 nm) (10 nm) (10 nm) (10 nm) (10 nm) (10 nm) (10 nm) (10 nm) NbN NbN NbN NbN NbN NbN NbN NbN (1.5 nm) (1.5 nm) (1.5 nm) (1.5 nm) (1.5 nm) (1.5 nm) (1.5 nm) (1.5 nm) Si3N4 Si3N4 Si3N4 Si3N4 Si3N4 Si3N4 Si3N4 Si3N4 (30 nm) (30 nm) (30 nm) (30 nm) (30 nm) (30 nm) (30 nm) (30 nm) - TiZrOx DLC y2o3 YZrOx YTiOx YHfOx YHfOx (5 nm) (lOnm) (lOnm) (5 nm) (5 nm) (5 nm) (5 nm)

[0081] The wear resistance of the stacks present on the glazing of examples 1 to 7 is measured as follows:

[0082] A 1 mm diameter stainless steel ball is repeatedly slid back and forth across the surface of the sample as shown in Examples 1 to 4, with a constant load of 10 N. Fifteen passes are made over a distance of approximately 10 mm. The average coefficient of friction (p) is recorded for each pass. For wear-resistant surfaces, the coefficient of friction is assumed to be low and constant.

[0083] The results of the wear resistance tests are presented in Table 2 below, where the values ​​of the coefficient of friction (p) are reported as a function of the number of back-and-forth movements (n):

[0084] [Tables2] n Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7 Ex. 8 2 0.20 0.12 <0.10 <0.10 0.12 <0.10 <0.10 <0.10 4 0.25 0.15 <0.10 <0.10 0.15 <0.10 <0.10 <0.10 8 0.6 0.45 <0.10 <0.10 0.20 <0.10 <0.10 <0.10 10 0.6 0.5 <0.10 <0.10 0.25 0.10 <0.10 <0.10 14 0.6 0.6 <0.10 <0.10 0.30 0.10 <0.10 <0.10

[0085] As shown in the preceding tables, the coating layers according The invention (examples 6 to 8) exhibits better scratch and wear resistance than TiZrOx layers and, unlike DLC layers, can undergo a tempering treatment, which is very important for this type of glazing, the stack of which is intended to be deposited on a monolithic glass substrate for the purpose of manufacturing a single pane of glass. Such panes are, in fact, most often tempered or ready for tempering.

[0086] A chemical durability test is also carried out on the different glazings reported in Table 1. This test consists of immersion in a solution of H2SO4 at a pH of 2.8 at room temperature, under agitation and for 30 minutes.

[0087] Table 3 below shows the results of the immersion test for the glazing in Examples 1 to 7 and the level of corrosion resistance observed visually. The (+) sign means that no trace of corrosion is visible on the surface of the glazing, the (-) sign that the surface is locally corroded, and (—) that the surface is completely corroded.

[0088] [Tables3] Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7 Ex. 8 Corrosion resistance -- + + - + + + +

[0089] It can be seen that the glazing of the stacks according to Examples 6 to 8 of the invention exhibits the best combined mechanical and chemical resistance performance. These qualities appear essential, particularly for its use as building glazing and especially as monolithic glazing, that is, comprising a single glass substrate, the stack being in this case often in direct contact with the external environment. In such glazing, the stack is indeed arranged on face 2 of the glazing, that is, on the face facing the interior of the building.

Claims

Demands

1. An article with antisolar properties comprising: - a glass substrate, - a stack of layers deposited on said substrate, - said stack comprising at least one functional layer absorbing and / or reflecting a portion of solar radiation and - a coating layer of said stack, wherein said coating layer is a dielectric oxide layer comprising yttrium, and at least one element selected from hafnium and titanium, wherein said coating layer comprises at least 10 atomic % of yttrium, based on the set of yttrium, titanium and hafnium atoms and wherein the coating layer constitutes the outermost layer of the succession of layers covering the glass surface.

2. Article according to claim 1, wherein said coating layer comprises on the basis of all yttrium, titanium and hafnium atoms present in said layer between 20 and 55 atomic % yttrium or even between 33% and 49% yttrium.

3. Article according to any one of the preceding claims, wherein the coating layer comprises at least 25 atomic percent of at least one element selected from hafnium and titanium, based on the total number of yttrium, titanium and hafnium atoms present in said layer, preferably more than 50 atomic percent of at least one element selected from hafnium and titanium.

4. Article according to any one of the preceding claims, wherein the atomic ratio (Hf+Ti) / Y in said coating layer is greater than 1.

5. Article one of the preceding claims, wherein the functional layer comprises a material selected from metallic niobium, niobium nitride, titanium nitride or titanium oxide, ITO, a layer comprising chromium, in particular a nickel-chromium alloy, optionally nitrided, or a layer consisting essentially of chromium.

6. Article according to any one of the preceding claims, in which the coating layer comprises less than 5 atomic percent of zirconium, preferably less than 1 atomic percent of zirconium, on the basis of all the yttrium, titanium, zirconium and hafnium atoms present in said layer, and preferably still is free of zirconium.

7. Article according to any one of the preceding claims, wherein the coating layer is yttrium titanium oxide.

8. Article according to any one of claims 1 to 6, wherein the coating layer is yttrium hafnium oxide.

9. Article according to any one of claims 1 to 6, wherein the coating layer is an oxide of yttrium, titanium and hafnium.

10. Article according to any one of the preceding claims, wherein the coating layer has a thickness of between 1 and 100 nm, preferably between 1 and 20 nm and most preferably between 2 and 10 nm, or even between 3 and 8 nm.

11. Article according to any one of the preceding claims, wherein the functional layer(s) has a physical thickness of between 2 and 50 nm, preferably between 5 and 30 nm.

12. Article according to any one of the preceding claims, wherein the stack comprises, above and / or below the functional layer or layers, silicon nitride-based layers, preferably having a physical thickness of between 1 and 100 nm, more preferably between 5 and 50 nm.

13. Article according to any one of the preceding claims, wherein the functional stack comprises or is constituted by the succession of at least the following layers, from the surface of the glass substrate: - a sublayer comprising silicon nitride, preferably of a thickness between 1 nm and 100 nm, - a functional layer preferably of a physical thickness between 2 and 50 nm, preferably between 5 and 30 nm, the functional layer comprising a material selected from metallic niobium, niobium nitride, titanium nitride or titanium oxide, an alloy of at least the elements Ni and Cr, optionally nitrided, - an overlayer comprising silicon nitride, preferably of a thickness between 1 nm and 100 nm.

14. Article according to any one of the preceding claims, wherein the stacking does not comprise layers based on silver, gold,

15. of platinum or copper. Article according to any one of the preceding claims in

16. wherein said article is tempered. Monolithic glazing for buildings, comprising an article according to one of the preceding claims.