Multiple glazing unit including at least one anti-glare coating, and use of an anti-glare coating in a multiple glazing unit

[0001] The invention relates to multilayer glazing comprising in the sense of the invention at least three substrates, a type of glass substrate, which are held together by a frame structure in which at least two intermediate gas layers are arranged, each between two substrates.

[0002] The invention relates in particular to triple glazing comprising three substrates, held together by a frame structure, two intermediate gas layers, each located between two substrates.

[0003] The invention further relates to the use of substrates for the production of multilayer glazing for thermal insulation and / or sun protection.

[0004] These multilayer glazing can be designed to fit buildings and vehicles, in particular to reduce the power of air conditioning and / or to prevent excessive overheating (glazing called "solar control") and / or to reduce the amount of energy dissipated outside (glazing called " low-emission ") caused by the ever-increasing size of glazed areas in buildings and vehicle cabins.

[0005] These glazing can further be included in glazing having special functions, such as heated glazing or electrochromic glazing.

[0006] The type of layer stack known to give substrates such thermal insulation and / or sun protection properties is formed of a functional metal layer with infrared and / or solar reflection properties, especially a functional metal layer based on silver or a metal alloy containing silver.

[0007] In this type of stack, the functional layer is therefore sandwiched between two dielectric coatings, usually comprising several layers each, each of which is of a nitride type dielectric material, in particular silicon nitride or aluminum or oxide type. From the point of view of optics, the purpose of these coatings that surround the metal functional layer is to "give anti-glare" to this metal functional layer.

[0008] However, sometimes a blocking coating is inserted between one or each dielectric coating and the functional metal layer, the blocking coating placed under the functional layer towards the substrate protects it during possible heat treatment at high temperature, such as bending and / or quenching, and a blocking coating disposed on the functional layer opposite the substrate protects this layer from possible damage during application of the upper dielectric coating and during possible heat treatment at high temperature, such as bending and / or quenching.

[0009] Currently, there are stacks of thin low-emission layers with only one functional layer (hereinafter referred to as "stack with one functional layer"), based on silver, having, when mounted in a traditional double glazing formed from two 4 mm glass panes separated by a gas layer of 90% argon and 10% air with a thickness of 16 mm, in which one of the panes is covered with a stack with one functional layer: the pane closest to the inside of the building when the direction of sunlight entering the building is being considered; on its surface facing the gas layer (configuration: 416 (Ar-90%) - 4, in which the stack with one functional layer is on the inner surface called "surface 3"):

- visible light transmittance TL of 75 to 80% and even more;

- Light reflection of visible light RL of 20 to 10%; and even less;

- solar factor (also called "g" or "g-value" in English) at least 0.6 and in the order of 0.63 to 0.68, or even more; and

- a heat transfer coefficient (also called "U value" or "U-value" in English) equal to or less than 1.5 and on the order of 1.2 to 1.1; and even slightly less.

[0010] In a structure of three glazing, the support substrate of the insulating coating may be on surface 2 and / or on surface 3 and / or on surface 5, when it is assumed that the direction of sunlight incidence passes through the surfaces in ascending order of their number and starting from the marking of the outermost surface number 1.

[0011] However, the inclusion of this (s) insulating coating (s), although it actually allows improving thermal insulation by reducing the heat transfer coefficient, however, reduces visible light transmission and reduces the solar factor.

[0012] Thus, multilayer glazing turns out to be less transparent in visible light than glazing has a high double factor, such as the previously shown glazing, and the energy gain inside the room through solar radiation is smaller.

[0013] The object of the invention is to overcome the disadvantages of the prior art, by using a new type of multilayer glazing that has light transmittance and high solar, at least light transmittance and solar factor similar to the light transmittance and solar factor of double glazing with enhanced heat insulation.

[0014] The object of the invention is therefore, in its broadest sense, a multilayer glazing according to claim 1. This glazing comprises at least three substrates that are held together by a frame structure in which at least two intermediate gas layers are arranged, each between two substrates, wherein at least one substrate comprises on at least one surface in contact with the intermediate gas layer an anti-reflection coating which is opposite to said medium gas layer, insulating coating with reflecting properties in infrared and / or solar radiation.

[0015] By "anti-reflection coating" is meant any element or any optical interference system having an exact refractive index or average refractive index which is between the glass refractive index (n factor of about 1.5) and the air factor (factor of about 1 ).

[0016] The optical factors (also called "refractive indexes") given herein are coefficients measured at 550 nm as usual.

[0017] The central substrate, which each of the two surfaces is in contact with the intermediate gas layer, preferably comprises, on at least one surface in contact with the intermediate gas layer, preferably on both surfaces thereof, an anti-reflection coating.

Preferably, opposite to all gas intermediate layers, one surface of the substrate comprises an anti-reflection coating, and the other surface of the other substrate comprises an insulating coating with infrared and / or solar radiation reflection properties.

In a variant, said insulating coating comprises an active system of the type of electrochromic system, and in another variant, said insulating eye coating comprises a stack of thin low emission or solar control layers, said stack comprising at least one functional layer with infrared reflection and / or in solar radiation, especially at least one functional metal layer, in particular based on silver or a metal alloy containing silver.

[0020] As part of this previous variant, said stack of thin layers preferably comprises at least one functional metal layer, based on silver or a metal alloy containing silver, and two dielectric coatings, each of said coatings comprising at least one dielectric layer , said functional layer is sandwiched between two dielectric coatings, the functional layer is optionally laid directly on the bottom blocking coating placed between the functional layer and the dielectric coating arranged below the functional layer and the functional layer the coating layer is optionally placed directly under the upper blocking layer placed between the functional and dielectric coating placed above the functional layer.

[0021] It is also possible to use a stack of thin layers, which contains only one metal functional layer based on silver or a metal alloy, the optical thickness of the functional layer arranged below (i.e. between the support substrate of the stack and the functional layer) is then preferably greater than the thickness of the optical dielectric coating above the functional layer containing silver, a dielectric coating wherein the ratio of the optical thickness of the dielectric coating laid down below to the optical thickness of the dielectric coating laid above is preferably between 1.05 and 1.4 including these values, optionally between 1.08 and 1.3 including these values.

[0022] It is also possible, independently or in addition to the previous solutions, to use a thin layer stack that contains only one metal functional layer based on silver or a metal alloy containing silver, said dielectric coating arranged below the functional layer preferably comprises a dielectric layer strongly refracting light rays, with this highly refracting layer having an optical factor greater than 2.2, and preferably comprised between 2.3 and 2.8 including these values, optionally comprised between 2.4 and 2.7 including these values.

[0023] The present invention also relates to the use according to claim 8. An anti-reflection coating is therefore used on at least one surface of at least one substrate to make a multilayer glazing according to the invention comprising at least three substrates, which are held together by a frame structure and in which each of the at least two intermediate gas layers is sandwiched between two substrates, what said anti-reflection coating contacts the intermediate gas layer and is opposite, relative to said gas intermediate layer, an insulating coating with infrared and / or solar radiation reflection properties.

[0024] Within this application, the surface (or surfaces) comprising said anti-reflection coating is (or are) preferably the surface (or surfaces) of the central substrate of the multilayer glazing, each of said surfaces being in contact with the intermediate gas layer.

[0025] Preferably, opposite to all intermediate gas layers, the surface of the substrate comprises an anti-reflection coating, and the other surface of the other substrate comprises an insulation coating with infrared and / or solar radiation reflection properties.

[0026] In an application variant, said insulating eye coating comprises at least one active electrochromic system type system, and in another variant, said insulating coating comprises a stack of low-emission or solar control thin layers, said stack comprising at least one functional layer with reflection properties in infrared and / or solar radiation, especially at least one functional metal layer, in particular based on silver or a metal alloy containing silver.

Also within this previous variant, said stack of thin layers preferably comprises at least one functional metal layer, based on silver or a metal alloy containing silver, and two dielectric coatings, each of said coatings comprising at least one layer dielectric, said functional layer is sandwiched between two dielectric coatings, the functional layer is optionally applied directly to the lower blocking coating sandwiched between the functional layer and the dielectric film stacked below the functional layer and the functional layer is optionally laid directly under the upper blocking shell sandwiched between the functional layer and the dielectric film stacked above the functional layer.

[0028] This stack of layers with one functional layer, when it is low-emission, has a low resistance per square meter (and therefore poor emissivity), high light transmittance and a relatively neutral color, especially in reflection from the layers side (but also from the opposite side: " sides of the substrate "), and these properties are preferably retained to a limited extent when the stack is or not subjected to high temperature bending and / or quenching and / or annealing heat treatment or heat treatment.

[0029] The dielectric layer, which is at least contained in each dielectric coating, as defined above, has an optical factor between 1.6 and 2.8 including these values, or, preferably, between 1.9 and 2, 2 including these values, unless it concerns a dielectric layer that strongly refracts light rays.

[0030] The low-emission stack of the invention is such that the resistance per square R in ohms per square functional layer (which is directly related to the emission capacity) is less than 10 ohms / square and on the order of about 5 to 3 ohms / square.

In a particular embodiment, the at least one dielectric coating, the lower dielectric coating and / or the upper dielectric coating, comprise (comprise) at least one dielectric layer based on silicon nitride, optionally doped with at least one other component, such as aluminum.

[0032] In a particular variant, the last layer of the lower dielectric coating, the layer furthest away from the substrate, is a moisturizing layer based on oxide, especially based on zinc oxide, optionally doped with at least one other component, such as aluminum.

[0033] In a very particular variant, the lower dielectric coating comprises at least one non-crystalline smoothing layer of mixed oxide, said smoothing layer being in contact with the underlying moisturizing crystalline layer, in particular a layer based on zinc oxide.

[0034] Preferably, the lower blocking coating and / or the upper blocking coating comprises a thin layer based on nickel or titanium having a geometric thickness e such that

0.2 nm <e and 1.8 nm.

[0035] In a particular version, at least one thin layer based on nickel, and blocking, contains chromium, massive 80% Ni and 20% Cr.

especially the top coating preferably in amounts ("overcoat" after protection) [0036] In another particular version, the at least one thin layer based on nickel, and especially the layer of the top blocking coating, contains titanium, preferably in mass quantities of 50% Ni and 50% Ti.

[0037] The last layer of the upper dielectric coating, the layer furthest from the substrate, is preferably oxide-based, preferably applied as a substoichiometric, and especially is titanium (TiOx) or mixed zinc and tin oxide (SnZnOx), or based on zirconia (ZrOx), possibly doped with another component in a ratio of up to 10% by mass.

[0038] The stack may thus comprise the last layer), i.e. preferably applied layer as sub-stoichiometric. This layer is oxidized substantially stoichiometrically in the stack after application. [0039] This protective layer preferably has a thickness between 0.5 and 10 nm.

[0040] In the glazing of the invention, any substrate can be monolithic and can be transparent, extrapolate or even colored.

[0041] In the glazing of the invention, at least one substrate may have a layered structure, in particular connecting at least two rigid glass-type substrates through at least one thermoplastic polymer pane to have a glass / pane (s) of polymer / glass. The polymer may in particular be based on polyvinyl butyral PVB, ethylene vinyl acetate EVA, polyethylene terephthalate PET, polyvinyl chloride PVC. [0042] Glazing substrates according to the invention are preferably capable of being subjected to heat treatment without harming the anti-reflective coating (s) and / or the insulating (s) coating (s).

[0043] These substrates are therefore optionally bent and / or hardened.

[0044] Advantageously, the present invention thus makes it possible to make multi-layer glazing, in particular triple glazing, presenting a favorable aesthetics very similar to that of double glazing (T_Lvis > 60%, R_Lvis > 30%, neutral colors in reflection), but with much better thermal insulation parameters and a solar factor similar to those of comparable double glazing.

[0045] Also preferably, the multilayer glazing comprises at least on one side an anti-reflection coating and on the other hand an insulating coating with reflection properties in infrared and / or solar radiation which are opposite each other in relation to the intermediate gas layer and which are thus both protected against harmful external activities. There is therefore no need to predict that these coatings will be mechanically and chemically resistant.

[0046] In addition, the glazing of the invention is easy to manufacture and allows achieving interesting energy characteristics at a low development cost.

[0047] The details and preferred characteristics of the invention will be more clearly apparent from the following non-limiting examples with reference to the accompanying drawings:

- figure 1 is a cross-sectional view of the prior art double glazing according to example 1;

- figure 2 is a cross-sectional view of the triple glazing according to example 2;

- figure 3 is a cross-sectional view of the triple glazing according to the invention, example 3;

- figure 4 is a cross-sectional view of another triple glazing according to the invention, example 4;

- figure 5 is a cross-sectional view of a quadruple glazing according to the invention; and

- figure 6 shows an insulating coating according to the invention comprising a stack with one functional layer, the functional layer being provided with a lower blocking coating and an upper blocking coating and the stack is further equipped with an optional protective coating.

[0048] In these figures, the proportions between the various elements are not observed to make them easier to read.

[0049] Figure 1 shows a prior art double glazing 80 (DGU) having the configuration: 4-16 (Ar-90%) - 4, i.e. consisting of two 4mm transparent glass panes, each of which is a substrate 10, 30, separated by an intermediate layer of gas 15 of 90% argon and 10% air 16 mm thick, all of which is held together by the frame structure 90.

[0050] One of the glass panes, substrate 30, is coated on its inner surface 29 facing the intermediate gas layer with an insulating coating 26 formed from a stack with one functional layer as described below: the pane closest to the interior of the building, when considered in the direction of sunlight entering the building represented by a double arrow directed in the figure from left to right (the stack with one functional layer is therefore on the inner surface called "surface 3").

[0051] This embodiment is the following example 1.

[0052] Figure 6 shows the structure of a stack with one functional layer applied to a glass substrate 30, in which the only functional layer 140 is sandwiched between two dielectric coatings, a lower dielectric coating 120 located under the functional layer 140 towards the substrate 30 and an upper dielectric coating 160 placed over functional layer 140 opposite to ground 30.

[0053] Each of these two dielectric coatings 120, 160 includes at least one dielectric layer

122, 124, 126; 162, 164, 166.

[0054] Optionally, on the one hand the functional layer 140 can be located on the lower blocking coating 130 sandwiched between the lower dielectric coating 120 and the functional layer 140, and on the other hand the functional layer 140 can be located directly under the upper blocking coating 150 sandwiched between the functional layer 140 and upper dielectric coating 160.

[0055] It can be seen in Figure 6 that the lower dielectric coating 120 contains three dielectric layers 122, 124 and 126, that the upper dielectric coating 160 contains three dielectric layers 162, 164, 166 and that this dielectric coating 160 is terminated with an optional protective layer, especially based on oxide, especially with sub-stoichiometric amount of oxygen.

[0056] The following table 1 shows the geometrical thicknesses (not optical thicknesses) in nanometers of each of the layers of the insulating coating that has been used for all examples 2 to 4 below:

Table 1

<td>Layer</td><td>Material</td><td></td>

<td> 166</td><td>SnZnOx: Sat.</td><td> 2</td>

<td> 164</td><td>si₃N₄Al</td><td> 25</td>

<td> 162</td><td>ZnO: Al</td><td> 5</td>

<td> 150</td><td>ti</td><td> 1</td>

<td> 140</td><td>Ag</td><td> 10</td>

<td> 126</td><td>ZnO: Al</td><td> 5</td>

<td> 124</td><td>TiO 2</td><td> 15</td>

<td> 122</td><td>SnO2</td><td> 15</td>

[0057] The lower dielectric coating 120 comprises a dielectric layer 122 of tin oxide SnO2 (factor n = 2.0) and at least one dielectric layer 124 highly refractive light rays of titanium oxide TiO2 (factor n = 2.4), said the dielectric layer 124 contacts the higher moisturizing dielectric layer 126, which allows the crystallization of silver to be improved, which improves its specific conductivity.

[0058] In this stack, the moisturizing layer, like dielectric layer 162, is of zinc oxide doped with aluminum ZnO: Al (coefficient n =

1.9), which was applied from a metal disk made of zinc doped in 2% by mass of aluminum.

[0059] The dielectric layer 164 is of silicon nitride Si3N4 doped in 8% by mass of aluminum (coefficient n = 2.0).

[0060] The dielectric layer 166 is a final and protective layer and is here of mixed zinc and tin oxide, which is doped with antimony (coefficient n = 2.0), this layer being applied from a metal disk formed according to mass ratios 65: 34: 1 respectively for Zn: Sn: Sat.

[0061] The optical thickness of the lower dielectric coating 120 is found to be: 15x2 + 15x2.4 + 5x1.9 = 75.5 nm and that the optical thickness of the upper dielectric coating 160 is: 5x1.9 + 25x2 + 2x2 = 63.5 ; so the ratio of optical thickness e120 / e160 = 1.19.

[0062] Triple glazing (TGU) was made on this basis.

[0063] Example 2 of multilayer glazing 100 consisting of triple glazing has been implemented. This glazing, shown in figure 2, has the configuration: 4-12 (Ar 90%) - 4-12 (Ar 90%) - 4, that is, it consists of three 4mm clear glass panes, each of which is a substrate of 10, 20, 30, separated by a vapor intermediate layer of gas 15, 25 with 90% argon and 10% air, each 12 mm thick, the whole being held together by the frame structure

90.

[0064] Each of the two outer substrates 10, triple glazing, is coated, on the inner surface 11, 29 facing the intermediate gas 15, 25, with an insulating coating of its layer 14, 26 formed from a stack with one functional layer as described above: stacks with one the functional layer are therefore on the surfaces called "surface 2" and "surface 5".

[0065] The central substrate 20 of this triple glazing, whose two surfaces 19, 21 are in contact with the intermediate gas layers 15 and 25, respectively, is not coated with any coating on any of its surfaces.

[0066] This example 2 allows for better thermal insulation than the double glazing insulation of example 1, which is manifested by a lower U-value, but the glazing light transmittance is less than the glazing light transmittance of example 1 and its solar factor is also lower.

[0067] In order to overcome this problem, according to the invention, example 3 of triple glazing is shown in figure 3. This triple glazing has the same multi-layer glazing configuration as example 2: 4-12 (Ar 90%) - 4-12 (Ar 90%) - 4, i.e. it consists of three 4mm clear glass panes, of which each is a substrate 10, 20, 30, separated by a vapor intermediate layer of gas 15, 25 with 90% argon and 10% air, each layer 12 mm thick, everything being held together by the frame structure 90.

As for example 2, each of the two external substrates 10, 30 of this triple glazing is coated, on its internal surface 11, 29 facing the intermediate gas layer 15, 25, with an insulating coating 14, 26 formed from a stack with one functional layer described above: stacks with one functional layer are therefore on surfaces called "surface 2" and "surface 5".

[0069] However, as part of example 3, each of the two surfaces 19, 21 of the central substrate 20 of this triple glazing, which are in contact with the intermediate air layers 15 and 25, respectively, are coated with an anti-reflection coating 18, 22.

[0070} This example 3 allows to obtain thermal insulation as good as the insulation of example 2, which is manifested by an identical U-factor, but the light transmission of the glazing is greater than the triple glazing of example 2 and its solar factor is also higher: so it is possible to obtain light transmittance and solar factor approximately identical to those in the double glazing of Example 1.

[0071] Another example of triple glazing, example 4, shown in figure 4, was implemented according to the invention. This triple glazing has the same configuration as examples 2 and 3: 4-12 (Ar 90%) - 4-12 (Ar 90%) - 4, that is, it consists of three 4mm clear glass panes, of which each is a substrate 10, 20, 30, separated by a vapor intermediate layer of gas 15, 25 with 90% argon and 10% air, each 12 mm thick, all held together by the frame structure 90.

[0072] However, as part of example 4, each of the substrates 20, 30 of this triple glazing is coated, on its inner surface 19, 29 facing the intermediate gas layer 15, 25, with an insulating coating 16, 26 formed from a stack with one functional layer described above: stacks with one functional layer are therefore on the surfaces called "surface 3" and "surface 5"; in addition, each of the surfaces 11, 21 of the substrates 10, 20 of this triple glazing, which are in contact with the intermediate layers of air and 25, respectively, are coated with anti-reflection coating 12, 22.

[0073] This example 4 makes it possible to obtain a thermal insulation as good as that of example 3, which is manifested by an identical U-value and heat transmission as high as the triple-glazing of example 3, but with a solar factor even higher than that of example 3.

[0074] For the examples of the invention, the anti-reflection coating 12, 18, 22 is formed of a stack of four thin structural layers:

Substrate / Si3N4 / SiO2 / Si3N4 / SiO2.

[0075] This coating therefore has, starting from the substrate, the order of the layers:

ratio, low high ratio, high ratio, low ratio. [0076] It was implemented according to the information from patent application No. WO international 2007/104874.

[0077] However, such a thin film coating can each be an equivalent coating replaced by any anti-reflective, especially anti-reflective based porous layer, such as layers known from the information from International Patent Application No. WO 2008/059170.

[0078] Such a thin film coating can also be replaced by any equivalent anti-reflective coating formed by etching the glass surface, such as the treatment known for example from US Patent No.

US 2,490,662; it is therefore possible to form a skeletal silicate structure having a refractive index between 1.0 and 1.3 on a thickness of 50 to 200 nm, and preferably 60 to 150 nm, on the surface of the substrate.

[0079] The following Table 2 summarizes the main parameters of Examples 1 to 4:

Table 2

<td>Layer</td><td>Ex. 1</td><td>Ex. 2</td><td>Ex. 3</td><td>Przykł.4</td>

<td>TLvis (%)</td><td> 80</td><td> 74</td><td> 79</td><td> 79</td>

<td>RLvis (%)</td><td> 12</td><td> 15</td><td> 10</td><td> 10</td>

<td>g</td><td> 0, 63</td><td> 0, 6</td><td> 0, 62</td><td> 0, 66</td>

<td>AT</td><td> 1,1</td><td> 0,7</td><td> 0,7</td><td> 0,7</td>

[0080] In this table, the optical and energy parameters presented consist of:

- TLvis, TL light transmittance in visible light in%, measured according to illuminating source D65,

- RLvis, RL light reflection in visible light in%, measured according to illuminating source D65,

- factor g, i

- U factor, in Wm^-2.K^-1.

[0081] In the usual manner throughout this document:

- coefficient g ("g-value" in English), means the solar factor, i.e. the ratio of total energy penetrating the premises through the glazing to the total incident solar energy. This ratio, calculated according to EN 410, is therefore between 0 and 1.

- U value ("U-value" in English), sometimes also called "K value", defines the heat transfer coefficient through the glazing. It determines the amount of heat passing through the partition, in a steady state, per unit area and for a unit temperature difference between environments located on both sides of the glazing, without taking into account the edge effects of the frame structure. It is usually, as in this case, calculated according to EN 673 and

-2 -1 is expressed in Wm^-2.K^-1.

[0082] It should be noted that for examples 2, 3 and 4, substrates 10, 20, 30 are of extra transparent glass marketed by SAINT-GOBAIN under the name Diamant.

[0083] Similar examples, numbered 2 ', 3' and

4 'were made using 10, 20, 30 standard glass substrates marketed by SAINT-GOBAIN under the name Planilux.

[0084] These media enable obtaining the parameters collected in the following table 3:

Table 3

<td>Layer</td><td>Ex. 2 '</td><td>Ex. 3 '</td><td>Ex. 4 '</td>

<td>TLvis (%)</td><td> 70</td><td> 75</td><td> 75</td>

<td>RLvis (%)</td><td> 14</td><td> 9</td><td> 9</td>

<td>g</td><td> 0,55</td><td> 0,57</td><td> 0, 60</td>

<td>AT</td><td> 0,7</td><td> 0,7</td><td> 0,7</td>

[0085] In addition, it was found that the solar factor and light transmittance could be increased by at least 1% and usually by about 2% by adding an anti-reflection coating on the outer surface of the triple glazing, i.e. on surface 1 or surface 6 that the solar factor transmittance light can each be increased by at least 2% and usually by about 4% by adding an anti-reflective coating on the two external surfaces of the triple glazing, that is, on surface 1 and on surface 6.

[0086] Three other examples, numbered 5, 6, 7, were implemented on the basis of examples 1 to 3, respectively, with the implementation of the insulating coating 14 in the form of an electrochromic element, i.e. a monolithic substrate 10 with a substrate containing an active system of the usual electrochromic type (not double), according to information from patent application No. EP 867 752 and EP 831 360.

[0087] The following table 4 provides a summary of the main parameters of examples 5 to 7 when electrochrome is not active:

replacing layered

Table 4

<td>Layer</td><td>Ex. 5</td><td>Ex. 6</td><td>Ex. 7</td>

<td>TLvis (%)</td><td> 59</td><td> 52</td><td> 55</td>

<td>RLvis (%)</td><td> 12</td><td> 14</td><td> 12</td>

<td>g</td><td> 0,4</td><td> 0,4</td><td> 0,4</td>

<td>AT</td><td> 1,3</td><td> 1</td><td> 1</td>

[0088] Also within this series of examples, the triple glazing solution of Example 7, which is in accordance with the invention, makes it possible to obtain a U-value thermal insulation, triple glazing as good as the thermal insulation of the triple glazing of Example 6, which is not in accordance with the invention . which is characterized by approximately identical but the heat transmittance of example 7 is higher than the transmittance of the triple glazing of example 6 and its solar factor is also identical: it is therefore possible to obtain light transmittance and solar factor approximately identical to that of the double glazing of example 2.

[0089] The use of an anti-reflective coating in a triple glazing containing an active system of the type of electrochromic system thus allows maintaining the level of transparency (visible light transmission) high in colorless form, and obtaining a high coefficient g in colorless form, which can be very useful for facade glazing buildings.

[0090] Active systems in the sense of the invention are usually electrochemical systems, and in particular systems that can be electrically controlled type systems with variable energy and / or optical parameters.

[0091] Electrically controlled systems allow, in particular, glazing in which the darkness / degree of vision or the filtration of heat / solar radiation can be freely changed. This applies, for example, to wiologen glazing that allows you to regulate light transmittance or absorption as described in US Patent No. US5,239,406.

[0092] There are also systems called "optical valves": this refers to polymer-based layers in which microdroplets are placed containing particles that can be positioned in a privileged direction under the influence of an electric field. An example of this is described in International Patent Application No. WO 93/09460. [0093] There are also liquid crystal systems with a mode of operation similar to the previous ones: they use a polymer layer sandwiched between two conductive layers and in which liquid crystal droplets are dispersed, especially nematic with positive dielectric anisotropy. When the layer is energized, the liquid crystals are oriented along the privileged axis, which allows vision. In addition to voltage, the layer becomes dispersed. Examples of this are described in patents EP-88 126, EP-268 877, EP238 164, EP-357 234, EP-409 442 and EP-964 288. Cholesteric polymers with liquid crystals such as those described in patent WO 92 may also be cited. / 19695 and systems with liquid crystals that commutate with a change in TL light transmittance.

[0094] There are also electrochromic glazing that allows modulation of light and heat transmission. They are described, in particular, in patents EP-253 713, EP-670 346, where the electrolyte is in the form of a polymer or gel and the other layers are of the mineral layer type. Another type is described in patent applications EP-867 752, EP-831 360, WO

00/57243, WO 00/03289, this time the electrolyte being in the form of an essentially mineral layer, the system layer layer is then essentially mineral: this type of electrochromic system is usually referred to as "completely solid". There are also electrochromic systems, where the set of layers is of the type electrochromic electrochromic surrounded by two plastic and polymer systems, then it is referred to as "completely polymeric".

[0095] Generally, they comprise two layers separated by an electrolyte layer with electrically conductive layers.

[0096] Each active system is supported by a substrate, which may be substrate 10, 20, 30. It may also be connected, without a gas intermediate layer, to at least one other substrate, or even several other substrates, regardless of whether they are (is) mineral (s) or synthetic (s): in this case, in the absence of a gas intermediate layer, the entire system assembly is considered to form an insulating coating in the sense of the invention.

[0097] Within the context of the present invention and throughout this text, the term "layer" should be considered in its broadest sense: this may apply to both mineral materials and minerals of the organic type, in particular polymers, which may be in the form of polymer layers or even gel layers. This may apply to an active system called hybrid, i.e. combining mineral, inorganic materials with organic materials, polymers.

[0098] It is also possible to consider triple glazing structures of substrate type 10 / SA1 / layer 15 / substrate 20 / layer 25 / SA2 / substrate 30, where SA1 and SA 2 specify two active systems identical or two active systems different or even two active systems coupled together.

[0099] Examples of active systems within the scope of the invention can also be found in patent application No. EP 240226, or No. EP 1775 625.

[0100] Figure 5 shows an example of quadruple glazing according to the invention. This quadruple glazing has the following configuration: 4-12 (Ar 90%) - 4-12 (Ar 90%) 4-12 (Ar 90%) - 4, that is, it is formed of four 4mm clear glass panes, with each of which is a substrate 10, 20, 30, 40 separated by a vapor intermediate layer of gas 15, 25, 35 with 90% argon and 10% air, each 12 mm thick, the whole being held together by the frame structure 90.

[0101] As in example 2, each of the two outer substrates 10, 40 of this quadruple glazing is coated, on its inner surface 11, 39 facing the intermediate gas layer 15, 35, with an insulating coating 14, 36 formed from a stack with one functional layer described previously: stacks with one functional layer are therefore on surfaces called "surface 2" and "surface 7".

As part of this quadruple glazing, each of the four surfaces 19, 21, 29, 31 of the two middle substrates 20, 30, which are in contact with the intermediate gas layers 15, 25 and 35, respectively, are coated with an anti-reflective coating 18, 22, 28 , 32.

[0103] This quadruple glazing makes it possible to obtain an even better thermal insulation than the insulation of example 3 and even example 4 with light transmittance and solar factor which are approximately identical to examples 3 and 4.

[0104] It is obvious that one skilled in the art is able to implement various variants of the invention without departing from the framework defined by the claims.

Saint-Gobain Glass France Full power:

41P34465PL00

EP 2 350 416 B1