Solar control and / or low-emissivity glazing

Abstract

The invention relates to a material comprising a substrate coated with a stack of layers comprising 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 arranged between two dielectric coatings, characterized in that the dielectric coating located above the functional metal layer comprises: - a zinc-based layer located in contact with the functional layer having a thickness of between 0.3 and 3.0 nm, and - a titanium oxide-based layer located above and in contact with the zinc-based layer having a thickness greater than or equal to 3.0 nm.

Description

Title of the invention: Solar control and / or low-emissivity glazing

[0001] The invention relates to a material comprising a transparent substrate coated with a functional coating capable of acting on solar radiation and / or infrared radiation. The invention also relates to glazing comprising these materials as well as the use of such materials for manufacturing thermal insulation and / or solar protection glazing. In the remainder of the description, the term “functional” qualifying “functional coating” means “capable of acting on solar radiation and / or infrared radiation”.

[0002] These glazings can be intended to equip both buildings and vehicles, in particular with a view to: - reduce air conditioning effort and / or prevent excessive overheating, so-called “solar control” glazing and / or - reduce the amount of energy dissipated to the outside, so-called “low emissive” glazing.

[0003] Silver-based functional metal layers (or silver layers) have advantageous electrical conduction and infrared radiation (IR) reflection properties, hence their use in so-called "solar control" glazing aimed at reducing the quantity of incoming solar energy and / or in so-called "low-emissive" glazing aimed at reducing the quantity of energy dissipated to the outside of a building or vehicle.

[0004] These silver layers are deposited between coatings based on dielectric materials generally comprising several dielectric layers (hereinafter "dielectric coatings") making it possible to adjust the optical properties of the stack. These dielectric layers also make it possible to protect the silver layer from chemical or mechanical attacks.

[0005] When seeking to develop solar control glazing, we seek to reduce the solar factor and increase light transmission and selectivity. When seeking to develop low-emissivity glazing, we seek to reduce emissivity and increase the solar factor. In all cases, we seek to minimize heat loss.

[0006] Emissivity and resistivity (or resistance) per square vary proportionally. Therefore, it is often possible to assess the emissivity of a material by assessing its resistance per square.

[0007] The solar factor of the glazing "FS or g" corresponds to the ratio in % between the total energy entering the room through the glazing and the incident solar energy. The solar factor therefore measures the contribution of a glazing to heating the "room". More the smaller the solar factor, the lower the solar gains.

[0008] Optical and electrical properties such as emissivity depend directly on the quality of the silver layers such as their crystalline state, their homogeneity as well as their environment. By "environment" is meant the nature of the layers close to the silver layer and the surface roughness of the interfaces with these layers. Another way to reduce emissivity therefore consists of improving the quality of the silver layer by choosing a favorable environment.

[0009] To improve the quality of silver-based functional metal layers, it is known to use dielectric coatings under the silver layers comprising dielectric layers with a stabilizing function intended to promote the wetting and nucleation of the silver layer. Dielectric layers based on crystallized zinc oxide are used in particular for this purpose. Indeed, the zinc oxide deposited by the cathode sputtering process crystallizes without requiring additional heat treatment. The zinc oxide-based layer can therefore serve as an epitaxial growth layer for the silver layer.

[0010] Another way to prevent the degradation of silver layers lies in the choice of the layer located above and in contact with the silver layer. Among the known proposals are the use of so-called blocking layers and / or dielectric layers based on crystallized zinc oxide. The objective is to protect the functional layers from possible degradation during the deposition of the upper dielectric coating and / or during a heat treatment.

[0011] The blocking layers are generally based on a metal chosen from nickel, chromium, titanium, niobium, or an alloy of these different metals. The different metals or alloys mentioned may also be partially oxidized, in particular have a sub-stoichiometry in oxygen (for example TiOx or NiCrOx).

[0012] These blocking layers are very thin, normally less than 2 nm thick, and at these thicknesses are susceptible to being partially oxidized during heat treatment or during deposition of an overlying layer. Generally speaking, these blocking layers are sacrificial layers, capable of capturing oxygen from the atmosphere or the substrate, thus preventing oxidation of the silver layer.

[0013] Materials comprising above the silver-based functional layer(s), a sequence of a nickel-chromium alloy-based blocking layer and a zinc oxide-based layer are currently used.

[0014] However, the use of these thin blocking layers, even when combined with zinc oxide-based stabilizing layers, does not make it possible to obtain sufficiently high-performance glazing units, in particular having a sufficiently low emissivity and good mechanical resistance. Indeed, it remains essential according to the invention that the advantageous emissivity properties are obtained without compromising mechanical strength. Good mechanical strength is reflected in good scratch and brush resistance, particularly in the EBT test (“Erichsen brush test”).

[0015] Good results in terms of resistivity have also been obtained with a material comprising, above the silver-based functional layer(s), a thick layer based on titanium oxide in contact with the silver. This layer is deposited from a ceramic target under stoichiometric conditions by controlling the oxygen in the deposition atmosphere. The Ag / TiOx sequence makes it possible to reduce the emissivity. In addition, the presence of this high refractive index layer in contact with the silver contributes: - to further improve the solar factor in the case where the stack is used as a low-emissivity stack on face 3 in double glazing, or - to improve selectivity in the case where the stack is used as a solar control stack on face 2 in double glazing.

[0016] However, when using this Ag / TiOx sequence, it is essential to carefully control oxidation during sputtering of the titanium oxide layer. If absorption in the titanium oxide-based layer is to be minimized, a significant proportion of oxygen in the deposition atmosphere is required. However, if excess oxygen is introduced during sputtering of the first nanometers of the titanium oxide layer, this causes oxidation of the silver. The resistivity of the silver is then degraded.

[0017] Finally, in the absence of oxygen or in the presence of a small amount of oxygen during the sputtering of the titanium oxide layer, a gain in resistance per square is observed. However, a higher absorption and degraded mechanical properties are also observed. This results in poor results in the EBT test. Control of the oxygen used during deposition is a key parameter.

[0018] The titanium oxide-based layer is advantageously deposited from a ceramic target, in particular under stoichiometric conditions, in a controlled atmosphere comprising oxygen. Preferably, a first thin thickness of titanium oxide-based layer is deposited in contact with the silver layer, from a ceramic target, in a non-oxidizing or very weakly oxidizing atmosphere. Then, a thicker thickness of titanium oxide-based layer is deposited from a ceramic target in an oxidizing atmosphere. The titanium oxide-based layer is made up of these two parts. During deposition, the part of the titanium oxide-based layer in contact with the functional layer is less oxidized than the part furthest from the functional layer. By proceeding in this way, we obtain both: - low resistance per square thanks to the Ag / TiOx interface deposited without oxygen and - low absorption thanks to the second part of the titanium oxide layer.

[0019] This multi-step deposition makes it possible to obtain predominantly in the stack a layer of titanium oxide with a large quantity of oxygen, while protecting the silver-based functional layer from a first layer of weakly oxidized titanium oxide. The absorption of the stack is then greatly reduced both in the absence of a heat treatment and following a heat treatment.

[0020] The Ag / TiOx sequence provides excellent performance and durability, provided that the deposition parameters are controlled. However, adjusting these parameters can be quite tricky. Both the optimum thicknesses and oxidation conditions must be determined for each part of the thick titanium oxide layer.

[0021] There is a need for a solution that can be used industrially and has superior performance achieved in a robust and reproducible manner, without requiring delicate, long and tedious adjustment times. There is also a need for a solution that can achieve these properties of low emissivity and good mechanical strength at the same time: - when the stack or the substrate carrying the stack has not undergone high temperature heat treatment and - when the stack or the substrate carrying the stack undergoes heat treatment at high temperature.

[0022] The applicant has surprisingly discovered that the combined use of a zinc-based layer deposited from a metallic zinc cathode combined with a thick titanium oxide-based layer in the dielectric coating located above the functional layer makes it possible to obtain the advantageous properties without requiring tedious adjustment of the deposition conditions of the layers constituting the stack. Thanks to the presence of the zinc-based layer, the titanium oxide-based layer can be deposited in a single step with high proportions of oxygen while ensuring low absorption. Thus, the deposition conditions are simpler and easier to determine industrially than the solution using the Ag / TiOx sequence.

[0023] The invention therefore relates to a material comprising a substrate coated with a stack of layers comprising at least one silver-based functional metal layer and at least two dielectric coatings, each dielectric coating comprising at least one dielectric layer, so that each functional metal layer is arranged between two dielectric coatings, characterized in that the dielectric coating located above the functional metal layer comprises: - a zinc-based layer located in contact with the functional layer having a thickness of between 0.3 and 3.0 nm, between 0.3 and 2 nm, between 0.3 and 1 nm or between 0.3 and 0.8 nm and - a titanium oxide-based layer located above and in contact with the zinc-based layer having a thickness greater than or equal to 3.0 nm.

[0024] The invention resulting from this combination makes it possible to obtain: - low resistivity values, - low absorption values, - good mechanical properties of brush resistance without and with heat treatment, - a simplified deposition process allowing properties to be obtained in a more robust manner.

[0025] But above all, the material of the invention has the advantage that these advantageous properties are obtained even when the coated material of the stack or the stack alone has not undergone heat treatment at high temperature. The materials according to the invention can be used indifferently:

[0026] - as filed, i.e. without having been subjected to any treatment high temperature thermal treatment, in this case neither the coated substrate of the stack, nor the stack alone, has undergone high temperature heat treatment,

[0027] - treated by laser radiation, in this case, only the stack undergoes treatment high temperature thermal, - treated by annealing or quenching, in this case the substrate and the stack undergo heat treatment at high temperature.

[0028] Obtaining properties regardless of the presence or absence of heat treatment allows greater flexibility in stock management. This is of significant economic interest.

[0029] The applicant has surprisingly discovered that the combined use of the zinc-based layer, the thick titanium oxide-based layer and a particular zinc and tin oxide-based layer also contributes to obtaining the advantageous properties of the invention. It appears that this layer makes it possible to reduce residual absorption in the event of incomplete oxidation of the titanium oxide-based layer.

[0030] The solution of the invention is particularly suitable in the case of stacks with several silver-based functional layers, in particular stacks with two or three functional layers which are particularly fragile from the point of view of scratches.

[0031] The present invention is also particularly suitable in the case of silver-based single-layer functional stacks intended for applications where, for example, high levels of light transmission are sought.

[0032] The material according to the invention may have the following characteristics alone or in combination: - the zinc-based layer is deposited from a metallic zinc target, - the titanium oxide-based layer is deposited from a ceramic target, in particular under stoichiometric conditions, preferably in an oxidizing atmosphere whose percentage in volume flow of oxygen represents between 0 and 20%, preferably 2 to 15%, - the titanium oxide-based layer has a thickness between 5 and 30 nm, - the titanium oxide-based layer comprises an oxidation gradient, the part of the titanium oxide-based layer in contact with the zinc-based layer is more oxidized than the part furthest away, - the dielectric coating located above the functional layer comprises a layer based on zinc and tin oxide comprising at least 10% by mass of tin relative to the total mass of zinc and tin, located above and in contact with the layer based on titanium oxide, - the layer based on zinc and tin oxide has a thickness: - greater than 5 nm, - less than 40 nm. - the dielectric coating located above the functional layer comprises a layer comprising silicon chosen from silicon nitride layers or silicon nitride and zirconium layers, - the dielectric coating located below the functional layer comprises a zinc oxide-based layer located in contact with the functional layer, - the dielectric coating located below the functional layer comprises a layer comprising silicon chosen from silicon nitride layers or silicon nitride and zirconium layers, - the dielectric coating located below the functional layer comprises a layer with a refractive index greater than 2.20, - the layer with a refractive index greater than 2.20 is chosen from layers based on titanium oxide and layers based on silicon and zirconium nitride, - the thickness of all layers with a refractive index greater than 2.20 in the dielectric coating located below the functional layer is greater than 10 nm, greater than 15 nm, greater than 20 nm, - the stack comprises a single functional metal layer based on silver, - the stack was subjected to rapid thermal annealing, - the stack and the substrate have been subjected to a heat treatment at a high temperature above 500°C such as quenching, annealing or bending.

[0033] The invention also relates to: - glazing comprising a material according to the invention, - glazing comprising a material according to the invention mounted on a vehicle or on a building, and - the process for preparing a material or glazing according to the invention, - the use of glazing according to the invention as solar control and / or low-emissivity glazing for buildings or vehicles, - a building, a vehicle or a device comprising glazing according to the invention.

[0034] The method for preparing a material according to the invention, the material comprising a substrate coated with a stack of layers comprising 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 arranged between two dielectric coatings, is characterized in that the dielectric coating located above the functional metal layer comprises: - a layer of zinc deposited in metallic form located in contact with the functional layer and - a titanium oxide-based layer located above and in contact with the metallic zinc layer.

[0035] Throughout the description, the substrate according to the invention is considered to be laid horizontally. The stack of thin layers is deposited above the substrate. The meaning of the expressions “above” and “below” and “lower” and “upper” is to be considered in relation to this orientation. In the absence of a specific stipulation, the expressions “above” and “below” do not necessarily mean that two layers and / or coatings are arranged in contact with each other. When it is specified that a layer is deposited “in contact” with another layer or a coating, this means that there cannot be one (or more) layer(s) interposed between these two layers (or layer and coating).

[0036] All the luminous characteristics described are obtained according to the principles and methods of European standards EN 410 relating to the determination of the luminous and solar characteristics of glazing used in glass for construction. It is considered that the sunlight entering a building goes from the outside to the inside.

[0037] According to the invention, the luminous characteristics are measured according to the illuminant D65 at 2° perpendicular to the material mounted in double glazing: - TL corresponds to the light transmission in the visible in %, - Rext corresponds to the external light reflection in the visible in %, observer on the external space side, - Rint corresponds to the interior light reflection in the visible in %, observer side interior space, - a*T and b*T correspond to the transmission colors a* and b* in the L*a*b* system, - a*Rext and b*Rext correspond to the colors in reflection a* and b* in the L*a*b* system, observer on the exterior space side, - a*Rint and b*Rint correspond to the reflected colors a* and b* in the L*a*b* system, observer side interior space.

[0038] As explained above, according to the invention the properties must be obtained even when the stack or the substrate carrying the stack has not undergone heat treatment at high temperature.

[0039] The present invention therefore relates to the coated substrate which has not been heat-treated. The stack may not have undergone heat treatment at a temperature above 500°C, preferably 300°C.

[0040] The present invention also relates to the heat-treated material. The heat treatments are chosen from: - annealing, for example rapid annealing, - quenching and / or bending.

[0041] The material, i.e. the transparent substrate coated with the stack, may have undergone a heat treatment at high temperature. The stack and the substrate may have been subjected to a heat treatment at a high temperature such as quenching, annealing or bending.

[0042] It is also possible to heat treat only the stack. In this case, only the stack may have undergone heat treatment.

[0043] In both cases, the stack may have undergone heat treatment at a temperature above 300°C, preferably 500°C. The heat treatment temperature (at the stack) is above 300°C, preferably above 400°C, and better still above 500°C.

[0044] According to the invention, it is possible to carry out a rapid thermal annealing process (Rapid Thermal Process) such as laser or flash lamp annealing. Rapid thermal annealing is for example described in applications WO2008 / 096089 and WO2015 / 185848. In these cases, only the stack is subjected to a heat treatment. During this type of treatment, each point of the stack is brought to a temperature of at least 300°C while maintaining a temperature less than or equal to 150°C at any point on the face of the substrate opposite that on which the stack is located. This process has the advantage of heating only the stack, without significant heating of the entire substrate.

[0045] In the case of laser treatment, the coated materials can be treated using a laser line formed from laser sources of the InGaAs laser diode or Yb:YAG disk laser type. These continuous sources emit at a wavelength between between 900 and 1100 nm. The laser line has a length of the order of 3.3 m, equal to the width 1 of the substrate, and an average half-height width FWHM between 45 and 100 pm.

[0046] The materials are arranged on a roller conveyor so as to move according to an X direction, parallel to its length. The laser line is fixed and positioned above the coated surface of the substrate with its longitudinal Y direction extending perpendicular to the X direction of travel of the substrate, i.e. along the width of the substrate, extending over this entire width. The position of the laser line focal plane is adjusted to be within the thickness of the functional coating when the substrate is positioned on the conveyor. The power flux density of the laser line at the focal plane is less than 100kW / cm2. The substrate was moved under the laser line at a speed of approximately 8 m / min.

[0047] The stack may therefore have been subjected to rapid thermal annealing in which each point of the stack is brought to a temperature of at least 300°C while maintaining a temperature less than or equal to 150°C at any point on the face of the substrate opposite that on which the stack is located.

[0048] It is also possible to combine heat treatments. For example, it is possible to carry out rapid thermal annealing followed by quenching.

[0049] The stack and the substrate may have been subjected to a heat treatment at an elevated temperature above 500°C such as tempering, annealing or bending. The coated substrate of the stack may be a curved or tempered glass.

[0050] The stack is deposited by magnetic field-assisted sputtering (magnetron process). According to this advantageous embodiment, all the layers of the stack are deposited by magnetic field-assisted sputtering.

[0051] In the absence of a specific stipulation, the expressions "above" and "below" do not necessarily mean that two layers and / or coatings are arranged in contact with each other. When it is specified that a layer is deposited "in contact" with another layer or a coating, this means that there cannot be one (or more) layer(s) interposed between these two layers (or layer and coating).

[0052] Unless otherwise stated, the thicknesses referred to in this document are physical thicknesses and the layers are thin layers. A thin layer is understood to mean a layer having a thickness between 0.1 nm and 100 micrometers.

[0053] In the present description, unless otherwise indicated, the expression "based on", used to qualify a material or a layer as to what it contains, means that the mass fraction of the constituent that it comprises is at least 50%, in particular at least 70%, preferably at least 90%.

[0054] The stack of thin layers comprises at least one functional layer and at least one at least two dielectric coatings comprising at least one dielectric layer, such that each functional layer is disposed between two dielectric coatings.

[0055] The stack of thin layers may comprise at least two silver-based metal functional layers and at least three dielectric coatings comprising at least one dielectric layer, such that each functional layer is arranged between two dielectric coatings.

[0056] The stack of thin layers may comprise at least three functional layers and at least four dielectric coatings comprising at least one dielectric layer, such that each functional layer is arranged between two dielectric coatings.

[0057] The silver-based metal functional layers comprise at least 95.0%, preferably at least 96.5% and more preferably at least 98.0% by mass of silver relative to the mass of the functional layer. Preferably, a silver-based metal functional layer comprises less than 1.0% by mass of metals other than silver relative to the mass of the silver-based metal functional layer.

[0058] The silver-based metallic functional layers have a thickness: - greater than 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 10 nm, 11 nm, 12 nm, 13 nm, 14 nm, 15 nm or 16 nm, and / or - less than 25 nm, 22 nm, 20 nm, 18 nm.

[0059] Dielectric coatings comprise dielectric layers. By "dielectric layer" within the meaning of the present invention, it is to be understood that from the point of view of its nature, the material is "non-metallic", i.e. is not a metal. In the context of the invention, this term designates a material having an n / k ratio over the entire visible wavelength range (from 380 nm to 780 nm) equal to or greater than 5. n designates the real refractive index of the material at a given wavelength and k represents the imaginary part of the refractive index at a given wavelength; the n / k ratio being calculated at a given wavelength identical for n and for k.

[0060] The thickness of a dielectric coating corresponds to the sum of the thicknesses of the layers constituting it. Preferably, the dielectric coatings have a thickness greater than 10 nm, greater than 15 nm, between 15 and 200 nm, between 15 and 100 nm or between 15 and 70 nm.

[0061] The dielectric layers of the coatings have the following characteristics alone or in combination: - they are deposited by magnetic field-assisted sputtering, - they generally have a thickness greater than 2 nm, preferably between 4 and 200 nm.

[0062] Dielectric layers, in addition to their optical function, can have various other functions. For example, stabilizing layers, smoothing layers, and barrier layers can be mentioned.

[0063] The dielectric layers are conventionally chosen from oxide-based, nitride-based or oxynitride-based layers. The oxide-based layers of one or more elements comprise essentially oxygen and very little nitrogen. The oxide-based layers comprise in particular at least 90% by atomic percentage of oxygen relative to the oxygen and nitrogen in said layer. The nitride-based layers comprise essentially nitrogen and very little oxygen. The nitride-based layers comprise at least 90% by atomic percentage of nitrogen relative to the oxygen and nitrogen in said layer. The oxynitride-based layers comprise a mixture of oxygen and nitrogen. The silicon oxynitride-based layers comprise 10 to 90% (limits excluded) by atomic percentage of nitrogen relative to the oxygen and nitrogen in said layer.

[0064] The amounts of oxygen and nitrogen in a layer are determined as atomic percentages relative to the total amounts of oxygen and nitrogen in the layer under consideration.

[0065] The dielectric layers are conventionally chosen from: - layers comprising silicon, aluminum and / or zirconium, optionally doped with at least one other element, - layers based on zinc and tin oxide, - layers based on titanium oxide, - layers based on zinc oxide.

[0066] According to the invention, a zinc-based layer is located in contact with the functional layer. In the following paragraphs, the zinc-based layers are defined as they are obtained during deposition. Since these layers are thin, it is not possible to determine with certainty, depending on the thicknesses deposited, how this zinc-based layer is modified following the deposition of the titanium oxide layer.

[0067] The zinc-based layer is deposited by sputtering from a metallic zinc target. The deposition atmosphere is oxygen-free or comprises very little oxygen, preferably oxygen-free, i.e. non-oxidizing. This zinc-based layer is partly oxidized to zinc oxide during the deposition of the titanium oxide-based layer. Following the deposition of the titanium oxide layer, there is preferably no absorption due to the non-oxidation of the metallic zinc. However, when the zinc-based layer is deposited in metallic form, the zinc appears to alloy or associate with the silver in the form of an AgZn phase. It is possible to carry out analyses proving the presence of this AgZn phase. When this phase is detected, there is a strong presumption that the zinc in contact with the silver has indeed been deposited at from a metal target in the absence of oxygen or under weakly oxidizing conditions.

[0068] The thickness of this layer can be as thin as that of a standard blocking layer ( <lnm), tant que la couche fonctionnelle à base d’argent ne s’avère pas dégradée par l’oxygène présent pendant le dépôt de la couche suivante à base d’oxyde de titane, déposée avec plus d’oxygène. Elle a une épaisseur comprise entre 0,3 et 3,0 nm, entre 0,3 et 2 nm, entre 0,3 et 1 nm ou entre 0,3 et 0,8 nm.

[0069] The zinc-based layers are deposited in metallic form. The zinc-based layers comprise at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% by mass of zinc relative to the total mass of elements other than oxygen and nitrogen in the zinc-based layer. The zinc-based layers may be chosen from: - zinc layers, - doped zinc layers, - zinc alloy-based layers.

[0070] According to the invention, the term "zinc layer" means metallic layers of pure zinc which may still include some impurities. In this case, the total mass of zinc represents at least 99% by mass relative to the total mass of elements other than oxygen and nitrogen in the zinc-based layer.

[0071] According to the invention, the doped zinc layers comprise at least 90.0%, at least 95%, at least 96%, at least 97% or at least 98% by mass of zinc relative to the total mass of elements other than oxygen and nitrogen in the zinc-based layer.

[0072] The doped zinc layers may be chosen from layers based on zinc and at least one element chosen from titanium, nickel, aluminum, tin, niobium, chromium, magnesium, copper, silicon, silver or gold.

[0073] According to the invention, the zinc alloy-based layers comprise at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80% or at least 90% by mass of zinc relative to the total mass of elements other than oxygen and nitrogen in the zinc-based layer.

[0074] The zinc alloy-based layers may be chosen from layers based on zinc and at least one element chosen from titanium, nickel, chromium, tin. By way of example, mention may be made of binary alloys of zinc and titanium such as Zn2Ti or ternary alloys based on zinc, nickel and chromium such as ZnNiCr.

[0075] The thickness of the zinc-based layer can be: - greater than or equal to 0.3 nm, greater than or equal to 0.5 nm and / or - less than or equal to 3.0 nm, less than or equal to 2.0 nm, less than or equal to 1.5 nm, less than or equal to 1.0 nm, less than or equal to 0.8 nm.

[0076] The stack comprises at least one titanium oxide-based layer located above and in contact with the zinc-based layer having a thickness greater than or equal to 3 nm. The layer is a titanium oxide-based layer over this entire thickness. According to the invention, this titanium oxide-based layer is part of a dielectric coating located above the silver layer. This means that when determining the thickness of this dielectric coating, the thickness of this layer is taken into consideration.

[0077] This thick titanium oxide-based layer near the silver contributes to obtaining the advantageous properties of the invention. This oxide layer is non-absorbent, especially when it is mainly deposited from a ceramic target in an oxidizing atmosphere.

[0078] The titanium oxide-based layers comprise at least 50%, at least 60%, at least 70%, at least 80%, at least 95.0%, at least 96.5% and better still at least 98.0% by mass of titanium relative to the mass of all the elements constituting the titanium oxide-based layer other than oxygen.

[0079] The layers based on titanium oxide can have a thickness: - greater than or equal to 3 nm, greater than or equal to 4 nm, greater than or equal to 5 nm, and / or - less than or equal to 30 nm, less than or equal to 25 nm, less than or equal to 20 nm, less than or equal to 15 nm, less than or equal to 10 nm, less than or equal to 8 nm, less than or equal to 6 nm. Titanium oxide-based layers can have a thickness between 5 and 30 nm.

[0080] The titanium oxide-based layers may comprise or consist of elements other than titanium and oxygen. These elements may be chosen from silicon, chromium and zirconium. Preferably, the elements are chosen from zirconium. Preferably, the titanium oxide-based layer comprises at most 35%, at most 20% or at most 10% by mass of elements other than titanium relative to the mass of all the elements constituting the titanium oxide-based layer other than oxygen.

[0081] Titanium oxide-based layers can be obtained: - by cathode sputtering, - from a titanium metal target or a ceramic target based on titanium oxide, preferably sub-stoichiometric. When the titanium oxide-based layer is obtained from a metal target, the deposition atmosphere includes significant proportions of oxygen. Titanium oxide-based layers are preferably obtained from a target titanium oxide ceramic, preferably under stoichiometric oxygen, in an atmosphere comprising oxygen. The quantity of oxygen in the deposition atmosphere can be adapted according to the desired properties. The titanium oxide-based layer is preferably deposited from a ceramic target, in particular under stoichiometric conditions in an oxidizing atmosphere, preferably in which the percentage of oxygen volume flow rate represents between 0 and 20%, preferably 2 to 15%.

[0082] According to the preferred embodiment, a titanium oxide-based layer is deposited from a ceramic target, in particular under stoichiometric. The titanium oxide-based layer may be deposited from a ceramic target of TiOx under stoichiometric, where x is a number different from the stoichiometry of titanium oxide TiO2, i.e. different from 2 and preferably less than 2, in particular between 0.75 times and 0.99 times the normal stoichiometry of the oxide. TiOx may in particular be such that 1.5 < x < 1.98 or 1.5 < x < 1.7, or even 1.7 < x < 1.95.

[0083] According to the invention, the deposit is carried out in an atmosphere comprising an optimized quantity of oxygen to obtain the desired properties. The deposition atmosphere comprises a mixture of noble gas (He, Ne, Xe, Ar, Kr) and oxygen. The noble gas is preferably argon. The following parameters make it possible to define the conditions for a cathodic sputtering deposition: - the deposition pressure, - the composition of the gases in volume flow (unit sccm “standard cubic centimeter per minute”). According to the invention, the following parameters were used: - the pressure in the deposition chamber is between 1 and 15 pbar, preferably 2 and 10 pbar or 2 and 8 pbar, - the deposition atmosphere includes a mixture of argon and oxygen.

[0084] The maximum oxygen threshold may vary to some extent depending on, for example: - the nature of the TiOx target, in particular its oxygen substoichiometry or - power, - the configuration of the sputtering deposition chamber (geometry, locations of gas inlets, etc.) Indeed, if a low deposition power is used, the quantities of oxygen volume flow that can be used during deposition will be lower because TiOx is deposited more slowly and is therefore more likely to oxidize.

[0085] A person skilled in the art is able to define a satisfactory controlled atmosphere by varying these parameters to a certain extent. A person skilled in the art is in particular perfectly able to determine the power to be applied to the target and the volume flow rates of oxygen and noble gases.

[0086] According to one embodiment, the titanium oxide-based layer is deposited from a ceramic target, in particular under stoichiometric conditions, in an atmosphere comprising oxygen.

[0087] According to one embodiment, a first thin thickness of titanium oxide-based layer is deposited in contact with the zinc-based layer, from a ceramic target, in a slightly oxidizing atmosphere. Then, a thicker thickness of titanium oxide-based layer is deposited from a ceramic target in a more oxidizing atmosphere. The thick titanium oxide-based layer according to the invention is made up of these two thicknesses. The part of the titanium oxide-based layer in contact with the zinc-based layer is less oxidized than the furthest part. The titanium oxide-based layer comprises an oxidation gradient, the part of the titanium oxide-based layer in contact with the zinc-based layer is more oxidized than the furthest part.

[0088] The titanium oxide-based layer is located below and in contact with a dielectric layer. The dielectric layer may be based on oxide, nitride or oxynitride of one or more elements chosen from silicon, zirconium, titanium, aluminum, tin and / or zinc. Preferably, this dielectric layer has a thickness greater than 5 nm, 8 nm, 10 nm or 15 nm.

[0089] The stack may comprise at least one layer comprising silicon or aluminum. Preferably, the dielectric coating located above the functional layer may comprise a layer comprising silicon, in particular chosen from silicon nitride layers or silicon nitride and zirconium layers. Each dielectric coating may also comprise at least one layer comprising silicon.

[0090] Layers comprising silicon are extremely stable to heat treatments. For example, no migration of the elements constituting them is observed. Consequently, these elements are not likely to alter the silver layer. Layers comprising silicon therefore also contribute to the non-alteration of the silver layers and therefore to obtaining low emissivity after heat treatment.

[0091] The layers comprising silicon comprise at least 50% by mass of silicon relative to the mass of all the elements constituting the layer comprising silicon other than nitrogen and oxygen.

[0092] The layers comprising silicon may be chosen from oxide-based, nitride-based or oxynitride-based layers such as silicon oxide-based layers, silicon nitride-based layers and silicon oxynitride-based layers.

[0093] The silicon oxide-based layers comprise at least 90 atomic percent oxygen relative to the oxygen and nitrogen in the silicon oxide-based layer. The silicon nitride-based layers comprise at least 90 atomic percent nitrogen relative to the oxygen and nitrogen in the silicon nitride-based layer. The silicon oxynitride-based layers comprise 10 to 90 atomic percent nitrogen relative to the oxygen and nitrogen in the silicon oxide-based layer. Preferably, the silicon oxide-based layers are characterized by a refractive index at 550 nm of less than or equal to 1.55. Preferably, the silicon nitride-based layers are characterized by a refractive index at 550 nm of greater than or equal to 1.95.

[0094] The layers comprising silicon may comprise or consist of elements other than silicon, oxygen and nitrogen. These elements may be chosen from aluminum, boron, titanium, and zirconium. The layers comprising silicon may comprise at least 2%, at least 5% or at least 8% by mass of aluminum relative to the mass of all the elements constituting the layer comprising silicon other than oxygen and nitrogen.

[0095] The layers comprising aluminum may be chosen from oxide-based, nitride-based or oxynitride-based layers such as aluminum oxide-based layers such as Al2O3, aluminum nitride-based layers such as AlN and aluminum oxynitride-based layers such as AlOxNy.

[0096] The layers based on silicon nitride and zirconium SixZryNz are part of the layers comprising silicon, in particular layers based on silicon nitride. The refractive index of the layers based on silicon nitride and zirconium increases with the increase in the proportions of zirconium in said layer.

[0097] The silicon nitride-based layers may comprise aluminum and / or zirconium. Such layers may comprise, in atomic proportion relative to the atomic proportion of Si, Zr and Al:

[0098] - 50 to 98%, 60 to 90%, 60 to 70 atomic % of silicon,

[0099] - 0 to 10%, 2 to 10 atomic % of aluminum

[0100] - 0 to 30%, 10 to 40% or 15 to 30 atomic % zirconium.

[0101] Preferably, the dielectric coating located above the silver layer comprises a layer comprising silicon. These layers comprising silicon have, in increasing order of preference, a thickness: - less than or equal to 40 nm and / or - greater than or equal to 5 nm, greater than or equal to 10 nm or greater than or equal to 15 nm.

[0102] Preferably, at least one dielectric coating comprises a layer comprising silicon chosen from layers based on silicon nitride. preferably, the dielectric coating located above the silver-based functional layer comprises a layer comprising silicon selected from silicon nitride-based layers. Each dielectric coating may comprise a layer comprising silicon selected from silicon nitride-based layers.

[0103] Preferably, the sum of the thicknesses of all the layers comprising silicon in the dielectric coating located above the first silver-based functional metal layer may be greater than 35%, greater than 50%, of the total thickness of the dielectric coating.

[0104] Preferably, the sum of the thicknesses of all layers comprising silicon nitride-based silicon in each dielectric coating located above the first silver-based functional metal layer may be greater than 35%, greater than 50%, of the total thickness of the dielectric coating.

[0105] The dielectric coating located above the functional layer may comprise a zinc and tin oxide-based layer comprising at least 10% by mass of tin relative to the total mass of zinc and tin, located above and in contact with the titanium oxide-based layer.

[0106] The layer based on zinc and tin oxide comprises in mass of tin relative to the total mass of zinc and tin: - at least 10%, at least 15%, at least 20%, at least 30%, at least 40%, at least 45%, at least 50% or at least 55%, - not more than 90%, not more than 80%, not more than 70%, not more than 65% or not more than 60% by mass of zinc. The zinc and tin oxide-based layer located in the dielectric coating above the silver-based functional layer has a thickness: - greater than 5 nm, greater than 10 nm, greater than 15 nm, greater than 18 nm, - less than 40 nm, less than 30 nm, less than 25 nm.

[0107] The dielectric coating located above the silver layer may comprise: - a zinc-based layer, - a layer based on titanium oxide, - a layer comprising silicon, preferably a layer based on silicon nitride or a layer based on silicon nitride and zirconium or a combination of these two layers.

[0108] The dielectric coating located above the silver layer may comprise: - a zinc-based layer, - a layer based on titanium oxide, - a layer based on zinc and tin oxide comprising at least 10% by mass of tin relative to the total mass of zinc and tin, located above and in contact with the layer based on titanium oxide, - a layer comprising silicon, located above and in contact with the layer based on zinc and tin oxide, preferably a layer based on silicon nitride or a layer based on silicon and zirconium nitride or a combination of these two layers.

[0109] The dielectric coating located below the functional layer may comprise a so-called stabilizing layer which reinforces the adhesion of the functional layer to the layers which surround it. The stabilizing layers are preferably layers based on zinc oxide optionally doped, for example, with aluminum. The zinc oxide is crystallized. The zinc oxide-based layer comprises, in order of increasing preference, at least 90.0%, at least 92%, at least 95%, at least 98.0% by mass of zinc relative to the mass of elements other than oxygen in the zinc oxide-based layer.

[0110] According to this embodiment, the dielectric coating located below the functional layer may comprise a zinc oxide-based layer located directly in contact with the functional layer. Indeed, it is advantageous to have a stabilizing layer, below and in contact with a functional layer, because it facilitates the adhesion and crystallization of the silver-based functional layer and increases its quality and stability. The metallic functional layer is deposited above and in contact with a zinc oxide-based layer. The zinc oxide-based layer may be deposited from a ceramic target, with or without oxygen, or from a metallic target. The zinc oxide layers have a thickness: - at least 1.0 nm, at least 2.0 nm, at least 3.0 nm, at least 4.0 nm, at least 5.0 nm, at least 6.0 nm and / or - not more than 25 nm, not more than 10 nm, not more than 8.0 nm.

[0111] The dielectric coating located below the silver layer may also comprise a zinc and tin oxide-based layer comprising at least 10% by mass of tin relative to the total mass of zinc and tin, located below and in contact with the zinc oxide-based layer.

[0112] The stack may therefore comprise one or more layers based on zinc and tin oxide comprising at least 10% by mass of tin relative to the total mass of zinc and tin, located above and in contact with the layer based on titanium oxide. The layers based on zinc and tin oxide preferably comprise by mass of tin relative to the total mass of zinc and tin: - at least 10%, at least 15%, at least 20%, at least 30%, at least 40%, at least 45%, at least 50% or at least 55%, - not more than 90%, not more than 80%, not more than 70%, not more than 65% or not more than 60% by mass of zinc. The zinc and tin oxide based layers have a thickness: - greater than 5 nm, and / or - less than 40 nm, less than 30 nm, less than 25 nm.

[0113] The dielectric coating located below the functional layer may comprise a layer comprising silicon selected from silicon nitride layers or silicon nitride and zirconium layers.

[0114] The dielectric coating located below the functional layer may comprise a layer with a refractive index greater than 2.20. The presence of high index layers above and below the silver-based functional layer contributes to obtaining high light transmission.

[0115] Among the dielectric layers, a distinction is made, depending on their refractive index at 550 nm, between low refractive index layers, intermediate refractive index layers and high refractive index layers. The low refractive index layers have a refractive index of less than 1.70. The intermediate refractive index layers have a refractive index of between 1.70 and 2.2. The high refractive index layers have a refractive index of greater than 2.2.

[0116] The high refractive index layers can be chosen from: - layers based on titanium oxide (n550=2.4), - layers based on mixed titanium oxide and another component chosen from the group consisting of Zn, Zr and Sn, - layers based on a layer of zirconium nitride (n 550 = 2.55), - layers based on silicon nitride and zirconium (n550 nm = 2.20 - 2.40), - layers based on a layer of zirconium oxide, - layers based on manganese oxide MnO (n550 = 2.16), - layers based on a layer of tungsten oxide (n550 = 2.15), - layers based on a layer of niobium oxide (n550 = 2.30), - layers based on a layer of bismuth oxide (n 550 = 2.60). Preferably, the high refractive index layer is chosen from layers based on titanium oxide and layers based on silicon and zirconium nitride.

[0117] Preferably, the stack does not comprise a metal or titanium oxide-based blocking layer below and in contact with the silver-based functional metal layer. In this case, the silver-based functional metal layer is located above and in contact with a dielectric layer of the dielectric coating. Preferably, this dielectric layer is a stabilizing layer.

[0118] The dielectric coating located below the functional layer may comprise a layer sequence, defined starting from the substrate, chosen from: - layer based on titanium oxide (high index layer) / / layer based on zinc oxide, - silicon nitride-based layer / / zinc oxide-based layer, - layer based on silicon nitride and zirconium (high index layer) / / layer based on zinc oxide, - silicon nitride-based layer / / silicon nitride and zirconium-based layer (high index layer) / / zinc oxide-based layer, - silicon nitride-based layer / / titanium oxide-based layer (high index layer) / / zinc oxide-based layer, - layer based on silicon nitride and zirconium (high index layer) / / layer based on titanium oxide (high index layer) / / layer based on zinc oxide, - layer based on silicon nitride / / layer based on silicon nitride and zirconium / / layer based on titanium oxide (high index layer) / / layer based on zinc oxide, - titanium oxide-based layer (high index layer) / / zinc and tin oxide-based layer / / zinc oxide-based layer, - silicon nitride-based layer / / zinc and tin oxide-based layer / / zinc oxide-based layer, - layer based on silicon and zirconium nitride (high index layer) / / layer based on zinc and tin oxide / / layer based on zinc oxide, - silicon nitride-based layer / / silicon nitride and zirconium layer (high index layer) / / zinc oxide and tin oxide-based layer / / zinc oxide-based layer, - silicon nitride-based layer / / titanium oxide-based layer (high index layer) / / zinc and tin oxide-based layer / / zinc oxide-based layer? - layer based on silicon and zirconium nitride / / layer based on titanium oxide (high index layer) / / layer based on zinc and tin oxide / / layer based on zinc oxide, - silicon nitride-based layer / / silicon nitride and zirconium layer / / titanium oxide-based layer (high index layer) / / zinc oxide and tin layer / / zinc oxide-based layer.

[0119] When the stack comprises a layer of silicon nitride and a layer of silicon and zirconium nitride, these layers are different, that is to say that they are not composed of the same elements in the same proportions.

[0120] The dielectric coating located above the functional layer may comprise a sequence of layers, defined starting from the substrate, chosen from: - the zinc-based layer / / the titanium oxide-based layer / / the silicon nitride-based layer, - the zinc-based layer / / the titanium oxide-based layer / / the silicon nitride and zirconium-based layer, - the zinc-based layer / / the titanium oxide-based layer / / the silicon and zirconium nitride-based layer / / the silicon nitride-based layer, - the zinc-based layer / / the titanium oxide-based layer / / the zinc and tin oxide-based layer / / the silicon nitride-based layer, - the zinc-based layer / / the titanium oxide-based layer / / the zinc and tin oxide-based layer / / the silicon oxide-based layer, - the zinc-based layer / / the titanium oxide-based layer / / the zinc and tin oxide-based layer / / the silicon and zirconium nitride-based layer, - the zinc-based layer / / the titanium oxide-based layer / / the zinc and tin oxide-based layer / / the silicon and zirconium nitride-based layer / / the silicon nitride-based layer, - the zinc-based layer / / the titanium oxide-based layer / / the zinc and tin oxide-based layer / / the silicon nitride-based layer / / the zinc and tin oxide-based layer, - the zinc-based layer / / the titanium oxide-based layer / / the silicon nitride-based layer / / the silicon oxide-based layer, - zinc-based layer / / titanium oxide-based layer / / zinc and tin oxide-based layer / / silicon nitride-based layer / / silicon oxide-based layer, - zinc-based layer / / titanium oxide-based layer / / silicon nitride and zirconium-based layer / / silicon nitride-based layer / / silicon oxide-based layer.

[0121] The stack of thin layers may optionally comprise a protective layer. The protective layer is preferably the last layer of the stack, i.e. the layer furthest from the coated substrate of the stack (before heat treatment). These layers generally have a thickness of between 0.5 and 10 nm, between 1 and 5 nm, between 1 and 3 nm or between 1 and 2.5 nm. This protective layer may be chosen from a layer of titanium, zirconium, hafnium, silicon, zinc and / or tin, this or these metals being in metallic, oxidized or nitrided form.

[0122] According to one embodiment, the protective layer is based on zirconium and / or titanium oxide, preferably based on zirconium oxide, titanium oxide or titanium and zirconium oxide. When determining the thickness of a dielectric coating, the thickness of the protective layer is taken into account.

[0123] The transparent substrates according to the invention are preferably made of a rigid mineral material, such as glass, or organic polymer-based (or polymer-based).

[0124] The transparent organic substrates according to the invention may also be made of polymer, rigid or flexible. Examples of polymers suitable according to the invention include, in particular: - polyethylene, - polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN); - polyacrylates such as polymethyl methacrylate (PMMA); - polycarbonates; - polyurethanes; - polyamides; - polyimides; - fluorinated polymers such as fluoroesters such as ethylene tetrafluoroethylene (ETFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), ethylene chlorotrifluoroethylene (ECTFE), fluorinated ethylene-propylene copolymers (FEP); - photocrosslinkable and / or photopolymerizable resins, such as thiolene, polyurethane, urethane-acrylate, polyester-acrylate resins and - polythiourethanes.

[0125] The substrate is preferably a sheet of glass or glass-ceramic. The substrate is preferably transparent, colorless (in which case it is a clear or extra-clear glass) or colored, for example blue, gray or bronze. The glass is preferably of the soda-lime-silica type, but it can also be of borosilicate or alumino-borosilicate type glass. According to a preferred embodiment, the substrate is made of glass, in particular soda-lime-silica or of polymeric organic material.

[0126] The substrate advantageously has at least one dimension greater than or equal to 1 m, or even 2 m and even 3 m. The thickness of the substrate generally varies between 0.5 mm and 19 mm, preferably between 0.7 and 9 mm, in particular between 2 and 8 mm, or even between 4 and 6 mm. The substrate may be flat or curved, or even flexible.

[0127] As explained previously, the solution of the invention is suitable: - for low-emissivity applications when an increase in light transmission and solar factor is required and - for solar control applications when increased selectivity is required.

[0128] The invention also relates to a glazing comprising at least one material according to the invention. The invention relates to a glazing which may be in the form of monolithic, laminated and / or multiple glazing, in particular double glazing or triple glazing.

[0129] Double glazing has 4 faces, face 1 is on the outside of the building and therefore constitutes the outer wall of the glazing, face 4 is on the inside of the building and therefore constitutes the inner wall of the glazing, faces 2 and 3 being on the inside of the double glazing. The stack according to the invention is on face 2 or face 3.

[0130] Triple glazing has 6 faces, face 1 is on the outside of the building and therefore constitutes the outer wall of the glazing, face 6 is on the inside of the building and therefore constitutes the inner wall of the glazing, faces 2 and 3 and 4 and 5 being on the inside of the double glazing. The stack according to the invention can be on face 2, face 3 and / or face 5.

[0131] A laminated glazing comprises at least one structure of the first substrate / sheet(s) / second substrate type. The polymeric sheet may in particular be based on polyvinyl butyral PVB, ethylene vinyl acetate EVA, polyethylene terephthalate PET, polyvinyl chloride PVC. The stack of thin layers is positioned on at least one of the faces of one of the substrates.

[0132] The invention therefore relates to: - a multiple glazing unit of the double glazing type with the stack on face 2, - a multiple glazing unit of the double glazing type with the stack on face 3, - a multiple glazing unit of the triple glazing type with the stack on face 2 and face 5, - a laminated glazing unit with the stack on face 2 or 3. These windows can be mounted on a building or a vehicle.

[0133] The following examples illustrate the invention. Examples

[0134] I. Preparation of substrates: Stacks, deposition conditions Thin film stacks defined below are deposited on clear soda-lime glass substrates with a thickness of 4 mm. In the examples of the invention: - the functional layers are silver (Ag) layers, - the dielectric layers are based on aluminum-doped silicon nitride (Si3 N4: Al), based on aluminum-doped silicon and zirconium nitride (SiZrN: Al), based on zinc and tin oxide (SnZnO), based on aluminum-doped zinc oxide (ZnO: Al). Titanium oxide TiOx layers are deposited from a TiOx ceramic target with or without oxygen in the deposition atmosphere. Zinc-based layers are deposited from an aluminum-doped zinc metal target. The deposition conditions of the layers, which were deposited by sputtering (so-called “magnetron cathode sputtering”), are summarized in Table 1.

[0135] [Tables 1] Material X Target composition Pressure Power Gas sccm Ar o2 n2 Ar / O2 (90 / 10) ZnO ZnO:Al 2%wt ceramic 2 pbar 1300 W 40 2 - - Zn Zn:Al 2%wt metallic 2 pbar 750 W 10 28 - - TiOx_0 % TiOx ceramic 2 pbar 2000 W 30 0 - - TiOx_5% TiOx ceramic 2 pbar 2000 W 20 0 - 20 SnZnO Sn:Zn 60 / 40%wt metallic 2 pbar 1000 W 7 44 Ag Ag metallic 8 pbar 210 W 80 - - - Si3N4 Si:Al 8%wt metallic 2 pbar 2000 W 18 - 24 - SiZrN Si:Zr 27% at metallic 2 pbar 1000 W 15 - 15 -

[0136] %wt: % by weight; at%: atomic.

[0137] Different stacks on glass substrate were tested. The materials according to the invention are intended to be used: - as deposited, i.e. without having been subjected to any high temperature heat treatment, hereinafter BT. Neither the substrate coated with the stack, nor the stack alone, has undergone high temperature heat treatment, - treated by laser radiation, hereinafter laser, in this case, only the stack undergoes heat treatment at high temperature, - treated in a Naber® oven at 650°C for 10 min, hereinafter “Naber®”, - treated by quenching, hereinafter “Quenched”.

[0138] Laser radiation treatment involves treating the coated substrates using a laser line formed from a disk laser. The following conditions were used: - disk laser source: Yb:YAG, - wavelength: 1030nm, - width: 60pm, - power density: 70kW / cm2.

[0139] The square resistance Rsq, corresponding to the resistance reported to the surface, is measured by induction with a Nagy SMR-12. Brush resistance tests were performed before and after heat treatment ("Erichsen brush test" before EBT heat treatment, after L-EBT laser heat treatment, after TT-EBT quenching heat treatment). Each sample is observed after 300 cycles. The Ok boxes indicate good resistance to the EBT or L-EBT test after 300 cycles, i.e. the absence of scratches or delamination. The Nok boxes indicate poor resistance to the EBT or L-EBT test after 300 cycles, i.e. the presence of scratches and / or delamination.

[0140] II. First series of tests The table below lists the materials and physical thicknesses in nanometers (unless otherwise indicated) of each layer or coating that constitutes the stacks according to their positions relative to the substrate carrying the stack.

[0141] [Tables2] Materials Layers Ref.la Ref.lb Ref.lc Ref.ld Lia Dielectric rev. TiOx 1.5 1.5 1.5 1.5 1.5 Si3N4 40 40 40 40 40 TiOx 5% - 0 5 4 5 TiOxO % - 5 0 1 - ZnO 5 - - - - Zn - - - - 0.5 NiCr 0.7 - - - - Functional layer Ag 11 11 11 11 11 Dielectric rev. ZnO 5 5 5 5 5 SiZrN 15 15 15 15 15 Si3N4 15 15 15 15 15 Substrate (mm) glass 4 4 4 4 4

[0142] The table below shows all the results, Rsq, Abs, and EBT and L-EBT tests.

[0143] [Tables3] Ref.la Ref.lb Ref.lc Ref.ld Lia Rsq Abs Rsq Abs Rsq Abs Rsq Abs Rsq Abs BT 4.6 9.1 4.1 9.0 6.9 9.1 4.4 7.7 4.4 7.1 Laser 3.6 6.0 3.0 6.4 3.6 4.7 3.0 5.3 3.3 4.7 Naber® 3.5 5.6 3.3 7.1 3.4 4.7 3.1 4.3 3.4 4.8 Hardened 3.5 5.7 3.2 7.9 4.3 12.5 2.9 5.6 3.3 5.1 EBT and L-EBT ok nok ok nok ok

[0144] 1, Materials as deposited For the as-deposited (BT) material, both the sheet resistance and absorption are degraded when using a titanium oxide layer deposited in an oxidizing atmosphere in contact with silver (comparison Ref.lc and Ref.la). This is due to excessive amounts of oxygen during the deposition of the titanium oxide-based layer and the resulting degradation of the silver. The introduction of the metallic zinc layer prevents the degradation of the silver layer even at such thin thicknesses (0.5 nm) and leads to the lowest absorption values ​​(7.1% for the example of the invention Lia compared to the references). But above all, the EBT of the stack according to the invention is satisfactory whereas this is not the case for the references Ref.lb and Ref.ld comprising in contact with the silver a layer of TiOx deposited without oxygen.

[0145] 2, Laser-treated materials A similar trend is observed for laser-treated stacks. The stack of the invention leads to the lowest absorptions. The resistance per square is satisfactory.

[0146] 3. Materials treated with Naber® In the case of stacks treated with Naber®, the stack of the invention exhibits both low absorption and low resistance per square and satisfactory mechanical properties.

[0147] II. Second series of tests In these examples, the influence of the presence of a layer of zinc and tin oxide in the dielectric coating located above the silver layer is tested.

[0148] [Tables4] Materials Layers Ref.2a Ref.2b Ref.2c Ref.2d I.2a Dielectric rev. TiOx 1.5 1.5 1.5 1.5 1.5 Si3N4 35 35 35 35 35 SnZnO 5 5 5 5 5 TiOx 5% - 0 5 4 5 TiOxO % - 5 0 1 - ZnO 5 - - - - Zn - - - - 0.5 NiCr 0.7 - - - - Functional layer Ag 11 11 11 11 11 Dielectric rev. ZnO 5 5 5 5 5 SiZrN 15 15 15 15 15 Si3N4 15 15 15 15 15 Substrate (mm) glass 4 4 4 4 4

[0149] [Tables5] Ref.2a Ref.2b Ref.2c Ref.2d I.2a Rsq Ab s Rsq Ab s Rsq Ab s Rsq Ab s Rsq Ab s BT 4.7 8.9 4.3 7.8 7.9 9.0 4.8 7.3 4.3 6.4 Laser 3.4 5.0 3.3 5.1 3.7 4.6 3.5 4.6 3.0 4.2 Naber® 3.3 5.3 3.9 5.6 3.4 4.5 3.5 4.8 3.1 4.5 Tempered 4.7 5.7 8.2 10.2 7.9 8.8 6.7 9.1 4.9 6.9 EBT and L-EBT ok nok ok ok ok TT EBT nok ok ok ok ok

[0150] 1, Materials as Deposited For the as-deposited (BT) material, both the sheet resistance and absorption are degraded when using a titanium oxide layer deposited in an oxidizing atmosphere in contact with silver (comparison Ref. 2c and Ref. 2a). This is due to excessive amounts of oxygen during the deposition of the layer based on titanium oxide and the resulting degradation of silver. The introduction of the metallic zinc layer prevents the degradation of the silver layer even at such thin thicknesses (0.5 nm) and leads to the lowest absorption values ​​(6.4% for the example of the invention I.2a compared to the references) and the lowest resistance per square values ​​(4.3Q / D). But above all, the EBT of the stack according to the invention is satisfactory whereas this is not the case for the references Ref.2b comprising in contact with the silver a layer of TiOx deposited without oxygen.

[0151] 2, Laser-treated materials For laser-treated stacks, a similar trend is observed. The stack of the invention leads to the lowest absorption and resistance values ​​per square inch (4.2% and 3.0Q / D). The introduction of the zinc and tin oxide layer leads to a significant improvement in resistance per square inch and absorption (Lia compared to I.2a). The L-EBT test of the stack according to the invention is satisfactory whereas this is not the case for the references Ref.2b comprising in contact with the silver a layer of TiOx deposited without oxygen.

[0152] 3. Materials treated with Naber® or tempering In the case of Naber®-treated stacks, the stack of the invention leads to the lowest absorption and resistance values ​​per square (4.5% and 3.1 Q / D). For the case of quenched stacks, the presence of the zinc and tin oxide-based layer in contact with the titanium oxide layer causes a redox reaction between the TiOx and the SnZnO leading to a degradation of the square resistance and absorption. All stacks comprising the TiOx / SnZnO sequence have degraded performances after quenching. However, surprisingly, the stack of the invention has a lower level of degradation.

Claims

Claims

1. Material comprising a substrate coated with a stack of layers comprising 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 arranged between two dielectric coatings, characterized in that the dielectric coating located above the functional metal layer comprises: - a zinc-based layer located in contact with the functional layer having a thickness of between 0.3 and 3.0 nm, and - a titanium oxide-based layer, located above and in contact with the zinc-based layer, having a thickness greater than or equal to 3.0 nm and less than or equal to 30 nm, deposited from a ceramic target.

2. Material according to the preceding claim characterized in that the zinc-based layer is deposited from a metallic zinc target.

3. Material according to any one of the preceding claims, characterized in that the titanium oxide-based layer is deposited from a sub-stoichiometric ceramic target.

4. Material according to any one of the preceding claims, characterized in that the titanium oxide-based layer has a thickness of between 5 and 30 nm.

5. Material according to any one of the preceding claims, characterized in that the titanium oxide-based layer comprises an oxidation gradient, the part of the titanium oxide-based layer in contact with the zinc-based layer is more oxidized than the furthest part.

6. Material according to any one of the preceding claims, characterized in that the dielectric coating located above the functional layer comprises a layer based on zinc and tin oxide comprising at least 10% by mass of tin relative to the total mass of zinc and tin, located above and in contact with the layer based on titanium oxide.

7. Material according to the preceding claim, characterized in that the layer based on zinc and tin oxide has a thickness: - greater than 5 nm, - less than 40 nm.

8. Material according to any one of the preceding claims, characterized in that the dielectric coating located above the functional layer comprises a layer comprising silicon chosen from silicon nitride layers or silicon nitride and zirconium layers.

9. Material according to any one of the preceding claims, characterized in that the dielectric coating located below the functional layer comprises a zinc oxide-based layer located in contact with the functional layer.

10. Material according to any one of the preceding claims, characterized in that the dielectric coating located below the functional layer comprises a layer comprising silicon chosen from silicon nitride layers or silicon nitride and zirconium layers.

11. Material according to any one of the preceding claims, characterized in that the dielectric coating located below the functional layer comprises a layer with a refractive index at 550 nm greater than 2.

20.

12. 12. Material according to the preceding claim, characterized in that the layer with a refractive index greater than 2.20 is chosen from layers based on titanium oxide and layers based on silicon and zirconium nitride.

13. 13. Material according to claim 11 or 12 characterized in that the thickness of all the layers with a refractive index greater than 2.20 in the dielectric coating located below the functional layer is greater than 10 nm.

14. Material according to any one of the preceding claims, characterized in that the stack comprises a single functional metal layer based on silver.

15. 15. Material according to any one of the preceding claims, characterized in that the stack has been subjected to rapid thermal annealing.

16. 16. Material according to any one of claims 1 to 14 characterized in that the stack and the substrate have been subjected to a heat treatment at a high temperature above 500°C such as quenching, annealing or bending.

17. A method of preparing a material according to any one of the claims- dications 1 to 16, the material comprising a substrate coated with a stack of layers comprising 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 arranged between two dielectric coatings, characterized in that the dielectric coating located above the functional metal layer comprises: - a layer of zinc deposited in metallic form located in contact with the functional layer and - a titanium oxide-based layer located above and in contact with the metallic zinc layer.