KR20210130422A - Manufacturing method of window glass with improved insulation through multi-layer coating - Google Patents

Abstract

The present invention relates to a method of manufacturing window glass with improved thermal insulation through multilayer coating deposited by cathode atomization, window glass with improved thermal insulation through multilayer coating, and crowned or tempered window glass with improved thermal insulation through multilayer coating. According to the present invention, at least one first transparent insulating layer is deposited, and a functional layer using an infrared reflective material as a main component is deposited. Thereafter, a first protective layer is deposited by a thickness of up to 3 nm by using a material in which an electronegativity difference with oxygen is less than 1.9, and a second protective layer is deposited by a thickness of up to 7 nm by using a material in which an electronegativity difference with oxygen is more than 1.4. Then, at least one second transparent insulating layer is deposited. The present invention is particularly advantageous for a sunlight blocking film that has been crowned or tempered after formation of a window glass unit having low emissivity or deposition of coating.

Description

The manufacturing method of window glass with improved insulation through multi-layer coating

The present invention provides thermal insulation through a multilayer coating deposited on a glass substrate by cathodic sputtering under reduced pressure and capable of withstanding heat treatments such as bending, annealing or thermal toughening or thermal tempering processes at elevated temperatures. This improved method for making glazing, and to glazing with improved thermal insulation through a multilayer coating that can withstand heat treatment at elevated temperatures.

The glazing units with multi-layer coating referred to in the present invention are used to reduce energy losses and heating costs in winter by improving the thermal insulation of large glazing surfaces. Multilayer coatings are low emissivity coatings with reduced heat loss through long wavelength infrared light. These glazing units can also be used as sun screens, reducing the use of air conditioners in summer months by reducing the risk of overheating by sunlight in confined spaces with large glazing surfaces.

These window glass units are designed to be suitable for buildings as well as automobiles. It is sometimes necessary to improve the resistance to mechanical stress by subjecting the glazing to a mechanical strengthening process, such as thermal toughening or thermal tempering. For example, in the automotive sector, it is often necessary to also bend the windowpanes, especially in order to shape them into the shape of a windshield.

In the method of manufacturing and forming glazing units, there are some advantages to a method of performing these toughening and bending processes on an already coated substrate instead of a method of coating the already formed substrate. However, since these processes are carried out at relatively elevated temperatures, the coating tends to deteriorate and lose its optical and infrared related properties.

It has been found that the deterioration of multilayer coatings is sometimes due to oxidation of the infrared reflective layer during heat treatment. A solution often proposed in an attempt to address this problem to form a glazing that retains essential characteristics even after heat treatment is to provide a sacrificial metal layer conveniently placed within the coating. This sacrificial metal protects this layer by being oxidized instead of a layer to reflect infrared light.

An example of such a solution is proposed in patent EP 233 003 B1, which describes the lamination of a silver-based layer as an infrared reflector surrounded by tin oxide. This patent provides an additional metal layer selected from aluminum, titanium, zinc and tantalum, which can be disposed over the silver layer and also below the silver. This additional metal traps oxygen and oxidizes during heat treatment, thereby protecting the silver from oxidation.

When in metallic form, the additional metal is absorptive and tends to reduce the light transmittance of the coating. Therefore, in order to obtain a final product with high light transmittance, the patent proposes to use the metal in an amount sufficient to protect the silver layer during heat treatment, but in an amount sufficient to prevent any absorptive additive metal from remaining in the final product. do. The amount of additional metal provided therefore depends on the heat treatment temperature and duration.

With the solution proposed by patent EP 233 003 B1, it may be difficult to obtain a product of consistent quality over a long manufacturing period, and in the case of a window glass of complex shape, it may be difficult to obtain a uniform quality over the entire surface. Also, when it is necessary to bend or toughen glazing units of different thicknesses or shapes, it is necessary to vary the temperature and time conditions of the heat treatment, so it is advisable to change the thickness of the additional metal to accommodate the variations in these treatment conditions. necessary.

The present invention relates to a method for manufacturing a glazing with improved thermal insulation through a multilayer coating deposited on a glass substrate by cathodic sputtering under reduced pressure, comprising the steps of depositing on the substrate at least one first transparent insulating layer, followed by infrared reflection depositing a functional layer based on a material, in an atmosphere containing up to 20% oxygen, having a geometric thickness of up to 3 nm, an electronegativity difference with oxygen of less than 1.9 and an electronegativity value of said infrared reflection depositing on said functional layer a first protective layer composed of a material less than the electronegativity value of the material, then in an atmosphere containing up to 50% oxygen, having a geometric thickness of up to 7 nm and electronegativity with oxygen depositing a second protective layer composed of a material with a difference greater than 1.4, followed by depositing at least one second transparent insulating layer.

The electronegativity values of elements as used in the present invention are average values classified according to the Pauling scale, and are obtained from thermochemical data. For clarity, the electronegativity values of some elements as follows are given below.

Ag 1.93 Au 2.54 Pd 2.20 Pt 2.28

Al 1.61 O ₂ 3.44 Si 1.90 Ti 1.54

Cr 1.66 Ni 1.90 Cu 1.65 Zn 1.81

Zr 1.33 Sn 1.96 Sb 2.05 Pb 2.33

Bi 2.02 Ta 1.5 Hf 1.3 In 1.78

The purpose of the transparent insulating layer is to reduce the light reflectivity of the coating by means of an interference effect, since a functional layer based on a material that reflects infrared light tends to reflect visible light as well. They are advantageous in the formation of glazing that reflects infrared rays while having a high light transmittance. These transparent insulating layers also serve to partially protect the functional layer against external physical or chemical stress, and the layer deposited on the substrate advantageously contributes to the adhesion of the coating to the glazing. These transparent insulating layers also influence the transmission and reflection behavior of the obtained product.

According to the present invention, the material of the first protective layer deposited directly over the functional layer has limited avidity for oxygen because the electronegativity difference with oxygen is less than 1.9, but also for oxygen rather than infrared reflecting materials. The high binding activity prevents oxygen from passing through the material. This is contrary to the teaching of the prior art, in which the functional layer is protected by a layer such as Ti or Ta having binding activity to oxygen, and this layer absorbs oxygen and prevents the functional layer from being oxidized. The essential properties of the functional layer are not lost.

Surprisingly, it has been found that the present invention provides a manufacturing method advantageous for the formation of glazings of stable and uniform quality. The method according to the invention allows a multilayer coating to obtain a glazing with improved thermal insulation and is particularly suitable for supplying production lines where the coating has to undergo heat treatment at elevated temperatures, such as bending, annealing or heat toughening processes. Indeed, even if the time and temperature conditions of the heat treatment vary somewhat during the manufacturing process or between one manufacturing cycle and another, these variations have a significantly less effect on the optical and thermal properties of the final glazing than when according to the prior art. In addition, if the coating structure is properly selected, there is no effect at all. Therefore, in the method according to the invention, it is not necessary to modify the coating structure according to the characteristics of the heat treatment to which the glazing must withstand.

Another advantage of the present invention is that, with proper selection of the transparent insulating layer, the method according to the present invention will yield a glazing with improved thermal insulation through a multilayer coating with little or only insignificant changes in the optical properties during heat treatment. It is possible that a glazing that withstands heat treatment can thereby be used in place of a glazing obtained by the same manufacturing method as the method according to the invention but which does not withstand heat treatment without aesthetically undesirable differences.

The rationale for this surprising effect is not fully understood. However, it is considered that bonding the first protective layer and the second protective layer to the functional layer under the conditions described in the present invention played an important role. Specifically, it is considered that since the material of the first protective layer has a relatively low binding activity to oxygen, its oxidation degree does not change suddenly, it does not reach saturation too quickly, and forms a stable film for the functional layer. Since the first protective layer is thin, not exceeding 3 nm in thickness, it can only have a limited effect on absorption of the coating, and it is easier to obtain an oxidation level sufficient to obtain good transparency. Therefore, this first protective layer serves to stabilize the properties of the coating. That is, since the material of the second passivation layer has sufficient binding activity to oxygen, it tends to retain oxygen and does not separate it too easily, it is possible to use the first passivation layer having a thin thickness.

Preferably, the first protective layer consists of a material having an electronegativity difference with oxygen of less than 1.8 and preferably less than 1.7.

Adoption of this electronegativity difference with respect to oxygen tends to enhance the effect of stabilizing the first layer.

Preferably, the second protective layer consists of a material having an electronegativity difference with oxygen of greater than 1.6 and preferably greater than 1.8. This enhances the affinity for oxygen of the second protective layer to more easily retain oxygen during heat treatment, thereby preventing diffusion of oxygen towards the functional layer.

Preferably, the electronegativity value of the first protective layer material is at least 0.05 less than the electronegativity value of the infrared reflective material. This reduces the risk of oxygen passing through the first protective layer to the functional layer during heat treatment.

Preferably, the second passivation layer material has an electronegativity value that is at least 0.1 and advantageously at least 0.2 less than the electronegativity value of the first passivation layer material.

It has been found that the use of a material having a smaller electronegativity value than that of the first protective layer as the material of the second protective layer enhances the beneficial effect of the present invention. Because the second protective layer has a higher binding activity to oxygen than the first protective layer, and thus the second protective layer tends to retain oxygen more easily, the difference in electronegativity between the two materials is the difference between the oxygen and the functional layer during heat treatment. It is thought to reduce the risk of going to

The functional layer mainly composed of an infrared reflecting material is, for example, a metal layer mainly composed of aluminum, copper, zinc, nickel or a noble metal such as gold, silver, platinum or palladium. The infrared reflecting material is preferably a silver-based material. Silver (Ag) is a very suitable material for use as a functional layer, since silver has good infrared reflectivity for its selling price and is easy to use in an apparatus that deposits the layer by cathodic sputtering under reduced pressure. The material may be pure silver, an alloy of silver with, for example copper, aluminum, or an alloy of silver with a small amount, usually on the order of 0.5 to 5%, palladium, copper, aluminum, gold or platinum, and preferably with palladium. can be

The first protective layer may be composed mainly of a material selected from, for example, zinc, copper, nickel, chromium, indium, stainless steel or tin in a metallic state or partially oxidized state, and alloys thereof.

Preferably, the first protective layer is a Ni-based alloy and advantageously a NiCr-based alloy. A particularly suitable alloy is the NiCr 80/20 alloy. Ni alloys may be deposited in the pure metallic state or in the partially oxidized or nitrided state or in the form of oxynitrides. This material has been found to be particularly well suited for forming a very thin stabilizing first protective layer which is advantageous for the formation of glazings with high light transmittance.

Preferably, the material of the second protective layer is selected from titanium, aluminum or tantalum and alloys thereof, advantageously titanium. These elements hold a large amount of oxygen and form a transparent oxide, so they are most suitable as the second protective layer for the purpose of the present invention.

Preferably, the first protective layer is deposited to a thickness ranging from 0.5 nm to 2.5 nm, advantageously from 0.5 nm to 2 nm, and most advantageously from 0.6 nm to 1.5 nm. This provides the best stabilizing effect discussed above.

Preferably, the second protective layer is deposited to a thickness in the range from 2 nm to 6 nm. It has been found that a thickness in this range for the second protective layer material is advantageous for retention of oxygen and protection of the functional layer.

The material of the second protective layer may be deposited in the form of a metal or in the form of a partial oxide that arises from the metal target in a neutral or lightly oxidized atmosphere. The material may also be deposited from a ceramic target of metal oxide in a relatively neutral atmosphere, for example an atmosphere containing 10 to 20% oxygen and the balance argon. The material is then advantageously substantially completely oxidized by the oxidizing plasma during deposition of the metal oxide forming part of the second transparent insulating layer, thereby becoming transparent after deposition, which promotes the formation of high light transmittance. After the entire coating has been deposited, the second protective layer is advantageously formed of TiO ₂ , Ta ₂ O ₅ or Al ₂ O ₃ .

If the next layer is an insulating layer deposited in an active atmosphere of nitrogen or a nitrogen-oxygen mixture, the second protective layer may be a transparent nitride or oxynitride, _{for example AlN or AlN x} O _{y after deposition of the coating.} have.

If the intended purpose with respect to the final optical properties of the manufactured glazing is lower light transmittance, the second protective layer may partially retain absorptivity and may contain an absorptive compound such as TiN or CrN or a reflective compound such as ZrN. .

The element designated for the second protective layer has a higher binding activity to oxygen than nitrogen. Even when partially or fully nitrided, they can capture and retain oxygen because they retain oxygen-related binding activity.

However, preferably the material of the second protective layer is deposited in metallic form or partially oxidized form and is then completely oxidized by the oxidizing plasma of the deposited layer. That is, it is possible to deposit an oxide from a metal target for forming the second transparent insulating layer.

Preferably, the second transparent insulating layer is mainly composed of an element different from the material of the second protective layer. This leads to the selection of elements which are particularly more suitable for the different roles by the two different layers.

The first and second transparent insulating layers can be formed using any transparent oxide, carbide, oxycarbide, nitride or oxynitride in a manner known in the art of coatings formed by cathodic sputtering under reduced pressure. Specifically, the following may be mentioned: nitrides, oxynitrides or oxides of silicon, chromium, zirconium or aluminum; carbides or oxycarbides of titanium, tantalum or silicon; carbide or oxycarbide of chromium; oxides of tin, zinc, titanium, bismuth, magnesium, tantalum, niobium, and indium; and also alloys of these different elements. Some elements may also advantageously be doped, for example zinc oxide or silicon oxide doped with aluminum.

Preferably, at least one of the first and second transparent insulating layers contains a zinc-based metal oxide. When silver is used as an infrared reflective material, this metal oxide exhibits a beneficial effect of passivating the silver, which makes the functional layer more resistant to chemical degradation, for example during heat treatment. Zinc is also a very suitable metal for cathodic sputtering under reduced pressure.

Preferably, the metal oxide is an oxide of a zinc-based and tin-based alloy. As pointed out above, zinc oxide is particularly advantageous. However, it tends to become porous when thickened. Zinc-tin alloys are particularly advantageous because this tendency is reduced. Advantageously, the at least one first and second insulating layer contains in different proportions two layers of oxides of zinc-based and tin-based alloys. This allows the proportion of zinc in the alloy to be appropriately adjusted for convenience, so that the insulating region closest to the functional layer has the highest concentration of zinc, which is advantageous for the beneficial effect of zinc, and the other insulating region has a lower concentration of zinc. to reduce the risk of layer porosity.

Advantageously, each of the first and second insulating layers contains a zinc-based metal oxide. Thereby, the beneficial effect of zinc is better ensured for the overall coating.

Previously, only a single functional layer was mentioned. This type of coating makes it easy to obtain low emissivity glazing units that are very useful for winter insulation. By making the functional layer thicker, it is also possible to obtain a glazing with increased sun protection. However, two or even three functional layers need to be deposited when an increase in sun protection is required while retaining a very high transmittance and a special aesthetically appealing appearance, as is generally the case with automotive windshields. Therefore, in a preferred embodiment of the method according to the invention, at least two functional layers based on an infrared reflective material are deposited, and then at least one intermediate insulating layer is deposited between each said functional layer.

Advantageously, the multilayer coating is completed by depositing a final protective layer of a thin film based on chromium, molybdenum, stainless steel, nickel or titanium, as well as alloys thereof, preferably based on titanium. This provides effective protection against scratches.

The invention also includes a method for producing curved or toughened glazing with improved thermal insulation by means of a multi-layer coating, characterized in that the substrate coated according to the method described above is subsequently subjected to a bending or toughening process.

According to another aspect, the present invention provides a glass substrate comprising at least one functional layer based on an infrared reflective material deposited thereon, said functional layer or at least one functional layer comprising at least one transparent insulating layer wherein the functional layer is in direct contact with the surface opposite the substrate, has a geometric thickness of up to 3 nm, has an electronegativity difference with oxygen of less than 1.9 and an electronegativity value less than the electronegativity value of the infrared reflective material. , coated with a first protective layer consisting of a metallic or semi-metallic material in metallic form or in nitrided or partially oxidized form, then having a geometric thickness of up to 7 nm and having an electronegativity difference of more than 1.4 with oxygen and immediately adjacent transparent A glazing with improved thermal insulation by means of a multilayer coating, characterized in that it is covered with a second protective layer composed of a material based on a metal or semimetal in a substantially completely oxidized form, different from the material of the insulating layer.

According to a further aspect, the present invention provides a glass substrate comprising at least one functional layer based on an infrared reflective material deposited thereon, said functional layer or at least one functional layer comprising at least one transparent insulating layer wherein the functional layer is in direct contact with the surface opposite the substrate and is composed of a metallic or semi-metallic material in oxidized or partially oxidized form, having a geometric thickness of at most 3 nm and an electronegativity difference of less than 1.9 with oxygen. metals or semimetals in substantially fully oxidized form, covered with a protective layer, having a geometric thickness of up to 7 nm, an electronegativity difference with oxygen greater than 1.4 and different from the material of the immediately adjacent transparent insulating layer; Curved or toughened glazing with improved thermal insulation by means of a multilayer coating, characterized in that it is covered with a second protective layer composed of a main component material.

According to this aspect of the invention, "curved or toughened glazing with improved thermal insulation through a multi-layer coating" should mean to undergo a toughening or bending heat treatment after the deposition process of the layers, and thus A toughening or bending process is performed.

The properties discussed above with respect to the structure, composition and arrangement of the different layers with respect to the method of the present invention also apply to the details relating to the glazing unit before and after heat treatment.

Preferred practical embodiments of the present invention will now be described by way of some non-limiting examples.

Example 1

One conventional soda-lime glass sheet having a width of 2 m, a length of 1 m, and a thickness of 4 mm was placed in a magnetron type cathode sputtering apparatus under reduced pressure manufactured by BOC. It is first sent to the first sputtering chamber, where the atmosphere is composed of 20% argon and 80% oxygen under a greatly reduced pressure compared to atmospheric pressure. First a first transparent insulating layer was deposited on the glass sheet. Using a cathode of a zinc-tin alloy containing 53% zinc and 48% tin, a 20 nm thick ZnSnO _x layer was first deposited. Then, another ZnSnO _x layer was then generated from a target of a zinc-tin alloy consisting of 90% zinc and 10% tin and deposited to a thickness of 12 nm _{on top of ZnSnO x in a similar atmosphere.} The glass sheet is then sent to another sputtering chamber, where the atmosphere is 100% argon. A functional layer consisting of 10 nm silver generated from a target that was in fact pure silver was deposited over the _{ZnSnO x layer.} A first passivation layer is then deposited over the silver in the same atmosphere, in an embodiment of the present invention, this first passivation layer being a 1 nm thick NiCr layer generated from a target of an alloy consisting of 80% Ni and 20% Cr. am. A second protective layer is then deposited over the NiCr layer in an atmosphere of 10% oxygen and 90% argon, which is achieved _by a 5 nm thick layer of TiO x (x is in the range of 1.6 to 1.9) _{generated from a ceramic target of TiO x .} was formed A second transparent insulating layer was then deposited over the _{TiO x} layer in another sputtering chamber in which the atmosphere was oxidized, ie consisting of 80% oxygen and 20% argon. _{To this end, a 10 nm thick ZnSnO x} layer, generated from a metal target of a ZnSn alloy consisting of 90% Zn and 10% Sn, was first deposited. It should be noted that the oxidation atmosphere of the plasma completes the oxidation of the _{lower layer TiO x , so that at the end of the ZnSnO x} layer deposition process, the titanium is essentially completely oxidized to form a compression barrier of _{TiO 2 . After deposition of the second transparent insulating layer, a 15 nm thick ZnSnO x} layer generated from a target of a ZnSn alloy consisting of 52% Zn and 48% Sn in an atmosphere of 80% oxygen and 20% argon was deposited. The coating was then completed by depositing a 3 nm TiO _{x final protective layer.} It should be noted that all ZnSnO _x layers have been sufficiently oxidized to be as transparent as possible.

Upon removal from the layer deposition apparatus, the freshly coated glazing had the following properties when viewed from the side of the layer:

TL = 80%; L = 23; a = -2; b = -13; Emissivity = 0.08.

The coated glazing was treated at a temperature of 690° C. for 4 minutes, and then subjected to a thermal tempering process in which cooling air was sprayed to quench it. During this heat treatment, the NiCr layer was oxidized enough to become transparent, and an effective and stable film protecting the silver was also formed. As can be seen from the properties of the coating after toughening below, since the silver layer was not oxidized despite the very thin NiCr film, this time the TiO2 layer seems to hold oxygen. Therefore, the combination of the first protective layer and the second protective layer exhibits a particularly advantageous effect in relation to the functional layer of silver.

After this treatment, the coated and toughened glazing, when viewed from the side of the layer, has the following properties:

TL = 88%; L = 24.4; a = -1.6; b = -8.6; emissivity = 0.05;

The electrical surface resistance of the coating was 3.8 Ω/sq., and the coefficient k (U-value) was less than 1.2 W/m 2 ·K.

This coated glazing is then assembled into a double glazing with another 4 mm clear glass sheet, the coating being placed in the direction of the interior space of the double glazing. When a double glazing is observed from the side of the layer in position 3, i.e., a transparent glass sheet without a layer is first observed, and then a glazing with a coating is observed from the side of the layer:

TL = 79.2%; L = 34.5; a = -1.4; b = -4.

In this example, as in the following examples, unless otherwise indicated, light transmittance (TL) is measured with respect to light sources C and L, and values a and b are values according to Hunter's Lab system.

As a variant, a second protective layer of TiOx was deposited from a metal target instead of using a ceramic target in an atmosphere of 20% oxygen, all other conditions being kept the same. The properties obtained for the coated glazing were identical.

Example 2

This was done using the same deposition process in all respects as the process described in Example 1, except that the deposition of the coating was carried out on a 6 mm thick glass sheet instead of 4 mm.

The glazing with this coating was treated at a temperature of 690°C for 6 minutes and then subjected to a thermal tempering process in which it was quenched by blowing cooling air. After this treatment, the coated and toughened glazing, when viewed from the side of the layer, has the following properties:

TL = 87.4%; L = 23.1; a = -1.3; b = -8.9; emissivity = 0.05;

The electrical surface resistance of the coating was 3.7 Ω/sq.

This coated glazing is then assembled into a double glazing with another 4 mm clear glass sheet, the coating being placed in the direction of the interior space of the double glazing. When the double glazing was observed from the side of the layer in position 3, the following properties were confirmed:

TL = 77.8%; L = 34.0; a = -1.2; b = -4.2.

When comparing Examples 1 and 2, varying the temperature and duration conditions of the thermal tempering process between the two examples in the same layer deposition process using the same coating structure significantly modified the optical, colorimetric and thermal properties. don't let The method according to the invention therefore allows a stable coating to be formed that is almost independent of the applied heat treatment.

Example 3

This was done using the same deposition process in all respects as the process described in Example 1, except that the deposition of the coating was carried out on an 8 mm thick glass sheet instead of 4 mm.

The glazing with this coating was treated at a temperature of 690°C for 8 minutes and then subjected to a thermal tempering process in which cooling air was sprayed to quench it. After this treatment, the coated and toughened glazing, when viewed from the side of the layer, has the following properties:

TL = 86.4%; L = 33.2; a = -1.6; b = -9.4; emissivity = 0.05;

The electrical surface resistance of the coating was 3.6 Ω/sq.

This coated glazing is then assembled into a double glazing with another 4 mm clear glass sheet, the coating being placed in the direction of the interior space of the double glazing. When the double glazing was observed from the side of the layer in position 3, the following properties were confirmed:

TL = 77.4%; L = 34.0; a = -1.2; b = -4.0.

Comparing Examples 1 and 3, varying the temperature and duration conditions of the thermal toughening process between the two examples in the same layer deposition process using the same coating structure is optical, colorimetric even when the period at elevated temperature is doubled. It does not significantly alter the mechanical and thermal properties. The method according to the invention therefore allows a stable coating to be formed that is almost independent of the applied heat treatment.

Example 4

In a magnetron-type apparatus for cathodic sputtering under reduced pressure, the coating was deposited on a 6 mm glass sheet in the following order. A first transparent insulating layer was deposited by forming a 10 nm thick aluminum nitride layer followed by a 20 nm thick zinc oxide layer doped with 5% aluminum. Aluminum nitride was deposited from an aluminum target in an atmosphere of 60% argon and 40% nitrogen. Zinc oxide was deposited from a target of zinc doped with 5% aluminum in an atmosphere of 70% oxygen and 30% argon. A functional layer consisting of 10.5 nm silver doped with 1% palladium was then deposited in a neutral atmosphere consisting of 95% argon and 5% oxygen. In the same neutral atmosphere, a first protective layer made of 0.8 nm zinc was deposited, followed by a second protective layer made of 4 nm tantalum. Subsequently, 15 nm of zinc oxide doped with 5% aluminum was deposited, followed by deposition of 17 nm of silicon nitride to form a second transparent insulating layer. Zinc oxide doped with aluminum was deposited in an oxidizing atmosphere of 70% _{O 2 and 30% Ar, and Si 3} N ₄ was deposited in 40% Ar and 60% nitrogen.

The properties of the coated glazing after deposition were as follows when viewed from the side of the layer:

TL = 84%; L = 25; a = 0; b = -12; Emissivity = 0.06.

This coated glazing is then assembled into a double glazing with another 6 mm clear glass sheet, the coating being placed in the direction of the interior space of the double glazing. When the double glazing was observed from the side of the layer in position 3, the following properties were confirmed:

TL = 75%; L = 36; a = 0; b = -6.

A single glazing with this coating was treated at a temperature of 690°C for 6 minutes and then subjected to a thermal tempering process in which cooling air was blown to cool it. After this treatment, the coated and toughened glazing, when viewed from the side of the layer, has the following properties:

TL = 86%; L = 23; a = -1; b = -10; emissivity = 0.04;

The electrical surface resistance of the coating was 3.4 Ω/sq.

By analyzing the properties of the glazing, it was found that the coating withstands the toughening process very well without arbitrary decomposition of the functional layer.

This coated and toughened glazing is then assembled into a double glazing with another 6 mm clear glass sheet, the coating being placed in the direction of the interior space of the double glazing. When the double glazing was observed from the side of the layer in position 3, the following properties were confirmed:

TL = 77%; L = 34; a = -1; b = -5.

It is noteworthy that, as the optical properties were virtually unchanged, glazing units, toughened or not, can be easily placed together in the same building.

Example 5

In a magnetron-type apparatus for cathodic sputtering under reduced pressure, the coating was deposited on a 2 mm thick glass sheet in the following order. In an atmosphere of 100% oxygen, a first transparent insulating layer 30 nm thick was deposited consisting of mixed zinc tin oxide deposited from a metal target of a zinc-tin alloy of 90% zinc and 10% tin. A functional layer of 10 nm silver was then deposited in a neutral atmosphere of 100% argon. On this silver layer, a 0.7 nm first protective layer of NiCr 80/20 was deposited in an atmosphere of 100% argon. _{On this first protective layer, a second protective layer comprising 3 nm TiO x} generated from a target of metallic titanium was deposited in an atmosphere of 20% oxygen. Then, an intermediate transparent insulating layer made of 70 nm of ZnSnO _x was deposited in the same manner as the first transparent insulating layer. The TiO _x layer was completely oxidized by plasma of _{ZnSnO x deposits.} A second functional layer of 10 nm silver was deposited followed by a first protective layer of NiCr 1.5 nm, both deposited in an atmosphere of 5% oxygen. Then, a second protective layer _{of TiO x} 2.5 nm was deposited from the metal target in 20% oxygen. A second transparent insulating layer was formed by _{20 nm of ZnSnO x} deposited in 100% oxygen. The plasma of the second insulating deposit completely oxidized _{the TiO x layer immediately below.} A titanium-based final protective layer of 3 nm was deposited to protect the coating.

The properties of the coated glazing after deposition were as follows when viewed from the side of the layer:

TL = 60%; L = 45; a = +3; b = +11; Emissivity = 0.05.

The window glass according to this embodiment is intended to be molded into the windshield of an automobile, wherein the coating provides a reliable sun protection effect to prevent excessive overheating of the passenger seat.

By performing a bending process on the coated window glass at a temperature of 650° C. for 12 minutes, the shape that the windshield should have was given.

After this treatment, the coated and curved glazing, when viewed from the side of the layer, has the following properties:

TL = 74%; L = 39; a = +5; b = +9; emissivity = 0.02;

The electrical surface resistance of the coating was 2.4 Ω/sq., which is an advantageous value for use as a heating layer.

A laminated glazing was formed by assembling the coated and curved glazing with a 2 mm thick transparent glass sheet using a 0.76 mm PVB film.

The characteristics at position 2 (position 1 is the outer surface of the windshield installed in the vehicle) of the glazing laminated by the layers are as follows:

TL = 75.5%; L = 35; a = -3; b = -4; Energy transmittance according to Moon = 45%; Energy reflectance according to Moon = 34%;

Here, the light transmittance was measured with respect to the light source A.

The coating was found to withstand the bending process very well.

Claims (48)

A method for producing glazing with improved thermal insulation through a multilayer coating deposited on a glass substrate by cathodic sputtering under reduced pressure, the method comprising: depositing on the substrate at least one first transparent insulating layer; then depositing a functional layer based on an infrared reflective material, in an atmosphere containing up to 20% oxygen, having a geometric thickness of up to 3 nm and an electronegativity difference with oxygen of less than 1.9 and an electronegativity value depositing over the functional layer a first protective layer composed of a material less than the electronegativity value of the infrared reflective material, then in an atmosphere containing up to 50% oxygen, having a geometric thickness of up to 7 nm and containing oxygen and thermal insulation through a multilayer coating, characterized in that it comprises the steps of depositing a second protective layer composed of a material having an electronegativity difference of greater than 1.4, followed by depositing at least one second transparent insulating layer The manufacturing method of this improved glazing. Method according to claim 1, characterized in that the first protective layer consists of a material having an electronegativity difference with oxygen of less than 1.8 and preferably less than 1.7. 3 . Thermal insulation through a multilayer coating according to claim 1 , characterized in that the second protective layer consists of a material with an electronegativity difference of more than 1.6 and preferably more than 1.8 with oxygen. A method for manufacturing an improved glazing. 4. Thermal insulation improved through multilayer coating according to any one of the preceding claims, characterized in that the electronegativity value of the first protective layer material is at least 0.05 less than the electronegativity value of the infrared reflective material. A method for manufacturing a window glass. 5. Thermal insulation through a multilayer coating according to any one of the preceding claims, characterized in that the second passivation layer material has an electronegativity value that is less than the electronegativity value of the first passivation layer material. A method for manufacturing an improved glazing. Thermal insulation through multilayer coating according to claim 5, characterized in that the second passivation layer material has an electronegativity value that is at least 0.1, and preferably at least 0.2, less than the electronegativity value of the first passivation layer material. The manufacturing method of this improved glazing. The method for manufacturing a glazing with improved thermal insulation through a multi-layer coating according to any one of claims 1 to 6, characterized in that the functional layer based on the infrared reflective material is an Ag-based layer. 8. The method for manufacturing a glazing with improved thermal insulation through a multi-layer coating according to any one of claims 1 to 7, characterized in that the first protective layer contains Ni as a main component. 9. Method according to claim 8, characterized in that the first protective layer consists mainly of NiCr, preferably NiCr 80/20 alloy. 10. Production of a glazing with improved thermal insulation by means of a multilayer coating according to any one of the preceding claims, characterized in that the second protective layer material is selected from titanium, aluminum or tantalum, preferably titanium. Way. 11 . The method according to claim 1 , wherein the first protective layer is deposited with a thickness in the range from 0.5 nm to 2.5 nm, preferably from 0.5 nm to 2 nm, and advantageously from 0.6 nm to 1.5 nm. A method for manufacturing a window glass with improved thermal insulation through a multi-layer coating, characterized in that. 12. Process according to any one of the preceding claims, characterized in that a second protective layer is deposited with a thickness ranging from 2 nm to 6 nm. 13. Multilayer according to any one of the preceding claims, characterized in that the second protective layer material is deposited in metallic or partially oxidized form and then subsequently oxidized by means of an oxidizing plasma of the deposited layer. A method of manufacturing window glass with improved thermal insulation through coating. 14. Method according to any one of claims 1 to 13, characterized in that the second transparent insulating layer mainly consists of an element different from that of the second protective layer material. . 15. Method according to any one of the preceding claims, characterized in that at least one of the first and second transparent insulating layers contains a zinc-based metal oxide. . The method of claim 15, wherein the metal oxide is an oxide of a zinc-based and tin-based alloy. 17. The glazing of claim 16, characterized in that at least one first and second insulating layer contains two layers of oxides of zinc-based and tin-based alloys in different proportions. manufacturing method. 18. A method according to any one of claims 15 to 17, characterized in that each of the first and second insulating layers contains a zinc-based metal oxide. 19. The method according to any one of claims 1 to 18, wherein at least two functional layers based on an infrared reflecting material are deposited, and then first and second protective layers are deposited on each, and between the functional layers at least A method for producing a glazing with improved thermal insulation through a multi-layer coating, characterized in that one intermediate insulating layer is deposited. Method according to any one of the preceding claims, characterized in that the multilayer coating is completed by depositing a final titanium-based protective layer. 21. A curved or toughened glazing with improved thermal insulation through multi-layer coating, characterized in that the coated substrate obtained by the method of any one of claims 1 to 20 is subsequently subjected to a bending or toughening process. manufacturing method. A glass substrate comprising at least one functional layer based on an infrared reflective material deposited thereon, said functional layer or at least one functional layer being surrounded by at least one transparent insulating layer, said functional layer comprising a substrate In direct contact with the opposite surface, the functional layer has a geometric thickness of up to 3 nm and has an electronegativity difference of less than 1.9 with oxygen and an electronegativity value less than the electronegativity value of the infrared reflective material, in metallic form or in nitride. coated with a first protective layer consisting of a metallic or semi-metallic material in an oxidized or partially oxidized form, which is then applied to a geometric thickness of up to 7 nm.
coated with a second protective layer comprising a material mainly composed of a metal or semimetal in substantially fully oxidized form, wherein the electronegativity difference with oxygen exceeds 1.4 and differs from the material of the immediately adjacent transparent insulating layer. glazing with improved thermal insulation through multi-layer coatings. 23. The glazing of claim 22 comprising at least two functional layers, each functional layer being covered with said first and second protective layers. 24. Multilayer coating according to claim 22 or 23, characterized in that the first protective layer or at least one first protective layer consists of a material with an electronegativity difference with oxygen of less than 1.8 and preferably less than 1.7. glazing with improved thermal insulation. 25. The method according to any one of claims 22 to 24, wherein the second protective layer or at least one second protective layer is composed of a material having an electronegativity difference with oxygen of greater than 1.6 and preferably greater than 1.8. A glazing with improved thermal insulation through a multi-layer coating. 26. The method according to any one of claims 22 to 25, characterized in that the electronegativity value of the first protective layer or at least one first protective layer material is at least 0.05 less than the electronegativity value of the infrared reflective material adjacent thereto. glazing with improved thermal insulation through multi-layer coatings. 27. A method according to any one of claims 22 to 26, characterized in that the second passivation layer or at least one second passivation layer material has an electronegativity value that is less than the electronegativity value of the first passivation layer material adjacent thereto. glazing with improved thermal insulation through multi-layer coatings. 28. The method according to claim 27, wherein the second passivation layer or at least one second passivation layer material has an electronegativity value that is at least 0.1, and preferably at least 0.2 less, than the electronegativity value of the first passivation layer material adjacent thereto. A glazing with improved thermal insulation through a multi-layer coating. 29. The method according to any one of claims 22 to 28, wherein the functional layer or at least one functional layer is based on Ag, and the first or first protective layers are based on an alloy of Ni and Cr, Wherein the second protective layer or the second protective layers are made of titanium oxide. 30. A glazing according to any one of claims 22 to 29, characterized in that at least one insulating layer is based on zinc oxide. 31. The glazing of claim 30, characterized in that at least one insulating layer contains an oxide of an alloy of zinc and tin. 32. The glazing of claim 31 wherein each insulating layer contains an oxide of an alloy of zinc and tin. A glass substrate comprising at least one functional layer based on an infrared reflective material deposited thereon, said functional layer or at least one functional layer being surrounded by at least one transparent insulating layer, said functional layer comprising a substrate In direct contact with the opposite surface, it is coated with a first protective layer consisting of a metallic or semi-metallic material in oxidized or partially oxidized form having a geometric thickness of up to 3 nm and an electronegativity difference of less than 1.9 with oxygen, followed by a maximum of 7 a second protective layer, having a geometric thickness of nm, an electronegativity difference with oxygen of greater than 1.4 and consisting of a material mainly composed of a metal or semimetal in substantially fully oxidized form, which differs from the material of the immediately adjacent transparent insulating layer A curved or toughened glazing with improved thermal insulation through a multi-layer coating, characterized in that it is coated with 34. The curved or toughened structure of claim 33 comprising at least two functional layers, each functional layer being covered with said first and second protective layers. window glass. 35. Multilayer coating according to claim 33 or 34, characterized in that the first protective layer or at least one first protective layer consists of a material with an electronegativity difference with oxygen of less than 1.8 and preferably less than 1.7. Curved or toughened glazing with improved thermal insulation. 36. The method according to any one of claims 33 to 35, wherein the second protective layer or the at least one second protective layer is made of a material having an electronegativity difference with oxygen of greater than 1.6 and preferably greater than 1.8. A curved or toughened glazing with improved thermal insulation through a multi-layer coating. 37. The method according to any one of claims 33 to 36, wherein the electronegativity value of the first protective layer or at least one first protective layer material is less than the electronegativity value of the infrared reflecting material adjacent thereto, preferably at least A curved or toughened glazing with improved thermal insulation through a multi-layer coating, characterized in that it is as small as 0.05. 38. A method according to any one of claims 33 to 37, characterized in that the second passivation layer or at least one second passivation layer material has an electronegativity value that is less than the electronegativity value of the first passivation layer material adjacent thereto. A curved or toughened glazing with improved thermal insulation through a multi-layer coating. 39. The method according to claim 38, wherein the second passivation layer or at least one second passivation layer material has an electronegativity value that is at least 0.1, and preferably at least 0.2 less than the electronegativity value of the first passivation layer material adjacent thereto. A curved or toughened glazing with improved thermal insulation through a multi-layer coating. 40. The method according to any one of claims 33 to 39, wherein the functional layer is mainly composed of Ag, the first protective layer or first protective layers are composed mainly of an alloy of Ni and Cr, and the second protective layer or The second protective layers are made of titanium oxide, and at least one insulating layer contains an oxide based on a zinc-based oxide, preferably a zinc-tin alloy. Curved or toughened panes. A preparation comprising a glass substrate and comprising, in succession thereon, at least one first transparent insulating layer, a silver-based functional layer, a nickel alloy in metal form directly in direct contact with the functional layer, a nitrided form, an oxidized or partially oxidized form of a nickel alloy. A multilayer coating, characterized in that there is deposited a first protective layer, a second protective layer deposited over and in direct contact with the first protective layer, and a second transparent insulating layer composed of a material different from that of the immediately adjacent second protective layer. glazing with improved thermal insulation. 42. The glazing according to claim 41, characterized in that the second protective layer has a geometric thickness of at most 7 nm. 43. A glazing according to claim 41 or 42, characterized in that the first protective layer has a geometric thickness of at most 3 nm. 44. The glazing according to any one of claims 41 to 43, characterized in that the first protective layer consists mainly of an alloy of nickel and chromium. 45. A glazing according to any one of claims 41 to 44, characterized in that at least one transparent insulating layer is based on zinc oxide. 46. A glazing according to any one of claims 41 to 45, characterized in that at least one transparent insulating layer is based on zinc oxide and tin oxide. 47. The heat treatment according to any one of claims 41 to 46, wherein a heat treatment such as a toughening and bending process is carried out, and the first protective layer is mainly composed of a nickel alloy, preferably nickel and chromium as the main components, the heat treatment A glazing with improved thermal insulation through a multilayer coating, characterized in that it is subsequently at least partially oxidized. 48. The method according to any one of claims 41 to 47, wherein at least two silver-based functional layers are deposited on a glass substrate and separated by at least one intermediate insulating layer and over each functional layer a first and a second A glazing with improved thermal insulation through a multi-layer coating, characterized in that the protective layer is deposited and in direct contact.