SK8342001A3 - Glazing panel - Google Patents

Abstract

A glazing panel carrying a coating stack comprises in sequence at least: a glass substrate, a base antireflective layer, an underlying barrier layer, an infra-red reflecting layer, an overlying barrier layer, and a top antireflective layer in which the underlying barrier layer comprises a mixture of Zn and at least one additional material X, in which the atomic ratio X/Zn in the underlying barrier layer is greater than or equal to 0.03 and in which X is one or more of the materials selected from the group comprising the materials of Groups (3a, 3b, 4a, 5a, 5b, 6b, 7b) of the periodic table. This provides an advantageous combination of properties, particularly thermal stability when such a glazing panel is bent and/or tempered.

Description

GLAZING PANEL AND METHOD OF ITS MANUFACTURING

Technical field

The present invention relates to glazing panes, in particular, but not only to glazing panes for controlling the passing of solar radiation, which are intended to be heat treated for applying a filter for regulating the passage of the solar radiation.

BACKGROUND OF THE INVENTION

EP 233003A discloses a glazing panel carrying an optical filter applied by sputtering having the following structure: glass substrate / base layer of dielectric formed of SnO ₂ / first metal barrier comprising Al, Ti, Zn, Zr or Ta / Ag / second metal barrier comprising Al, Ti, Zn, Zr or Ta / dielectric outer layer formed by SnO ₂ . Said optical filter is designed to block a substantial portion of the incident radiation in the infrared region of the spectrum while allowing a substantial portion of the radiation to pass through the visible region of the spectrum. The filter thus formed serves to reduce the heating effect of the incident solar radiation, while at the same time allowing good visibility through said glazing panel, and such a glazing panel is particularly suitable for the production of automobile windscreens.

In the above type of structure, the silver layer serves to reflect the incident infrared radiation and in order to fulfill this task, the layer must be metallic silver rather than silver oxide and must not be contaminated by adjacent layers. The layers of said dielectric adjacent to said silver layer on both sides serve to reduce the reflection of radiation in the visible region of the spectrum that would otherwise be caused by said silver layer. The second metal barrier serves to prevent oxidation of the silver layer during the formation of the outer layer of dielectric consisting of SnO ₂ , whereby

31736 h ·· this layer is formed by sputtering in an oxidizing atmosphere; said process at least partially oxidizing said metal barrier. The main purpose of the first metal barrier is to prevent oxidation of the silver layer during heat treatment of said optical filter applied to the glass sheet (i.e. during bending and / or tempering of the glass sheet), the protective effect of this layer being that to oxidize this layer as to allow oxygen to pass to the silver layer. This oxidation of the metal layer during the heat treatment of the glass causes an increase in the TL value of the glazing panel.

European Patent Application Publication No. EP 792847A discloses a heat-treatable glazing panel for regulating the passage of solar radiation, which was formed on the same principle and had the following structure: glass substrate / dielectric layer formed by ZnO / Zn barrier / Ag / Zn barrier / layer formed by ZnO / Zn barrier Ag / Zn barrier / ZnO dielectric layer. The zinc (Zn) barriers located under each layer of silver are intended to be completely oxidized during the heat treatment of such a glass sheet and serve to protect the silver layer from oxidation. It is also known in the art that an increase in selectivity of a given optical filter can be achieved by means of said structure comprising two separate silver layers rather than by a structure comprising a single silver layer.

In European Patent Application Publication No. EP 275474A, a heat-treatable glass sheet for regulating the passage of solar radiation has been described having the following structure: a glass substrate / zinc stannate / Ti / Ag / Ti / tin stannate dielectric. Titanium (Ti) barriers are generally used in this type of heat-treatable structure, due to their high affinity for oxygen and their relatively easy oxidability to form titanium.

31736 h ·· ·· ·· ·· · ······ · · · · φ · φ · · · φ · φ · φ φ ·

SUMMARY OF THE INVENTION

Unless otherwise indicated by context, the following abbreviations, symbols, and formulas have the following meanings:

a ' the chromaticity coordinate measured on the CIELab scale at normal radiation incidence Ag silver Al aluminum AI ₂ O ₃ aluminum oxide AIN aluminum nitride b ' the chromaticity coordinate measured on the CIELab scale at normal radiation incidence bi bismuth Cr chrome turbidity percentage of light transmitted passing through a sample that differs from the incident beam by scattering in the forward direction, determined according to ASTM D 1003-61 (which was amended in 1988) H hafnium material reflecting infrared radiation a material whose reflection coefficient in the wavelength range from 780 nanometers to 50 micrometers is greater than that of soda-lime glass On the sodium nb niobium NiCr an alloy or mixture containing nickel and chromium NiTi an alloy or mixture containing nickel and titanium RE energy reflection amount of sunlight (visible

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or invisible) reflected from the underlying material, expressed as a percentage of the incident solar radiation sb antimony selectivity the ratio of the amount of visible sunlight transmitted to the solar factor, i. TL / TE ratio SiO ₂ silicon dioxide Si ₃ N ₄ silicon nitride SnO ₂ tin (IV) oxide the tantalum TE energy permeability the amount of sunlight (visible or invisible) passing through base material, expressed as a percentage of incident solar radiation you titan TL visible transmittance amount of visible radiation passing through the substrate, expressed as a percentage of the incident visible radiation Zn zinc ZnAl alloy or mixture containing zinc and aluminum ZnAlOx mixed oxide containing zinc and aluminum ZnAlOy partially oxidized mixture containing zinc and aluminum ZnO zinc oxide ZnTi an alloy or mixture containing zinc and titanium ZnTiOx mixed oxide containing zinc and titanium ZnTiOy partially oxidized mixture containing zinc and titanium Zr zirconium

31736 h · · · · · · · · · · · · · · ·

One aspect of the present invention is a glazing panel as defined in claim 1 below.

The formation of said substrate barrier in the form of a mixture of Zn and one of said other elements provides an advantageous combination of properties. The underlying barrier must not only fulfill its essential role of protecting the silver layer from undesirable oxidation during heat treatment of the sheet, but also, for example, must also be compatible with the other layers contained in the layered coating of the present invention, be mechanically and chemically resistant and suitable. for industrial scale production.

Any suitable method or any suitable combination of methods may be used to apply the individual layers of the coating of the present invention. For example, evaporation (by heat or electron beam), liquid pyrolysis, chemical vapor deposition, vacuum deposition and sputtering can be used, particularly magnetron sputtering, which is used particularly advantageously in the practice of the present invention. The individual layers of the laminate coating of the present invention can be applied in various ways.

The underlying barrier of the present invention may provide a preferred combination of:

- heat resistance in protecting the silver layer which overlaps the barrier from degradation during heating of the glazing according to the invention, for example during tempering and / or bending of the glazing. It should be noted that the tolerance to changes in the temperature cycle to which the glazing panel of the present invention is subjected can be greater than that achieved, for example, by the use of known substrate barriers including Ti or Zn;

31736 h · · · · · · · · · · · · · · _a · ···· «« 6 · · · · · · · · · · • · · · a · «AAAAA · • ···· ···· ···· ·· ·· ·· ·· and ··

- mechanical resistance: said substrate barrier may have greater adherence to the adjacent silver layer than, for example, a barrier comprising aluminum (Al). This adhesion may be higher even if the backing layer of the present invention comprises aluminum (Al);

silver compatibility (Ag): crystallization of said silver layer affects the optical properties of the silver layer. A layer of pure zinc (Zn) or zinc oxide (ZnO) serving as a substrate for said silver layer can lead to excessive crystallization of silver and problems with the turbidity of such a coating, especially when the coating is subjected to heat treatment. These problems can be controlled or reduced by the present invention while promoting crystallization of said silver layer to a degree sufficient to provide good infrared reflectance properties.

Said advantageous properties of the substrate barrier according to the present invention cannot be achieved if the atomic ratio X / Zn is less than a given minimum, for example if the element X is present in the form of an impurity in the zinc (Zn). Said atomic ratio X / Zn may be less than about 5; alternatively, the ratio may be equal to or less than about 4 or about 3. This ratio may provide a zinc (Zn) content in said substrate barrier sufficient to provide advantageous properties of the barrier.

Said backing barrier is preferably applied in the form of a metal or suboxide and serves not only to block the passage of oxygen to the silver layer, but also to diffuse light ions, in particular sodium (Na), of said glass backing material into said silver layer. This barrier therefore has to fulfill other functions associated with the fact that it also serves as a topsheet and therefore various factors have to be taken into account in its selection.

31736 h · · ··· ··· · · · ··· · · · ··· ·

Particularly good results can be obtained when element X is one or more elements selected from the group consisting of aluminum (Al), titanium (Ti), hafnium (Hf), antimony (Sb), niobium (Nb), tantalum (Ta) and zirconium (Zr).

The thickness of said backing layer may be greater than about 5 Å; preferably it is greater than about 10 Å; wherein such thickness can provide a remarkable improvement in the properties of the coating of the present invention when the coating is subjected to heat treatment. The thickness of said backing layer may be equal to or less than about 50 Å, especially when the element X is titanium (Ti); equal to or less than about 40 Å, especially when the atomic ratio X / Zn is equal to or less than about 3; equal to or less than about 30 Å, especially when atomic X / Zn is equal to or less than about 1; equal to or less than about 25 Å, especially when the element X is aluminum (Al).

The aforementioned thicknesses of the underlying barriers may impart a suitable level of stability to the coating of the present invention in its heat treatment. However, the optimum thickness of the backing layer is influenced by the particular composition of the barrier layer, the deposition conditions, the desired optical properties of the glazing panel and the thermal regime to which the glazing panel is optionally subjected.

The infrared reflecting material of the present invention may be silver or silver alloys, such as a silver alloy, comprising, as an additional element, one or more elements selected from the group consisting of palladium (Pd), gold (Au) and copper (Cu). Such an additional element may be present in said silver alloy in an atomic ratio of from 0.3 percent to 10 percent, preferably from 0.3 percent to 5 percent and more preferably, especially when said further element is palladium (Pd), from 0.3 to 10 percent. 2 percent, based on the total amount of silver and other metal.

31736 h • · • ···

One or more of said antireflective layers may comprise an oxide, a nitride, a carbide or a mixture thereof. The antireflective layer of the present invention may include, for example:

an oxide of one or more of zinc (Zn), titanium (Ti), tin (Sn), silicon (Si), aluminum (Al), tantalum (Ta) or zirconium (Zr); zinc oxide containing aluminum (Al), gallium (Ga), silicon (Si) or tin (Sn) or indium oxide containing tin (Sn);

a nitride of one or more elements selected from the group consisting of silicon (Si), aluminum (Al) and boron (B) or a mixture (including double zirconium nitride (Zr) or titanium (Ti) with one of the above nitrides;

a mixed compound such as SiOxCy, SiOxNy, SiAlxNy or SiAlxOyNz.

The antireflective layer of the present invention may be a single layer or may comprise two or more layers which differ in composition. Particular preference is given to using zinc oxide, preferably zinc oxide containing at least one of tin (Sn), chromium (Cr), silicon (Si), boron (B), magnesium (Mg), indium (In), gallium (Ga) and preferably aluminum (Al) and / or titanium (Ti), since the use of such materials facilitates the formation of a stable adjacent layer with high crystallinity that reflects infrared radiation.

As further defined in claim 2, a preferred combination of properties obtainable by the underlying barrier layer of the present invention can be utilized in a layered coating comprising two or more spaced apart infrared reflecting layers. Each of said infrared reflecting layers may be provided with a backing barrier layer and in such cases at least one, but preferably all of said backing barrier layers comprise the above elements.

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Several spaced-apart infrared reflecting layers may be used to form a glazing panel having a selectivity greater than 1.5 or 1.7.

Thus, the present invention presents particular advantages associated with heat-treated and heat-treated glazing panels, but can also be used in the case of glazing panels that are not heat treated in any way. The term "heat-treatable glazing panel" as used herein means that the glazing on which the coating is applied is adapted to be subjected to bending and / or thermal tempering and / or heat curing and / or other heat treatment processes. without the turbidity of the glazing thus treated exceeding 0.5, preferably without the turbidity of the glazing thus treated exceeding 0.3. The term "substantially non-turbid heat treated glazing panel" as used herein refers to a glazing panel on which a laminate coating has been applied, which has been subjected to bending and / or thermal tempering and / or thermal curing and / or other thermal process after applying said laminate. The opacity of the glazing thus treated does not exceed 0.5, preferably the opacity of the glazing thus treated does not exceed 0.3. Such heat treatment processes may include heating the glazing on which the laminate is applied, or exposing the sheet to temperatures above about 560 ° C, such as exposing the sheet to a temperature in the range of 560 ° C to 700 ° C, under normal atmosphere. . Another such heat treatment process may be the sintering of ceramic or enamel material, sealing of the double glazing unit under vacuum and annealing of the low-reflection layer or the anti-glare layer applied by a wet process. Said heat treatment process, particularly with respect to bending and / or heat tempering and / or heat curing, may be carried out at a temperature of at least 600 ° C for at least 10 minutes, 12 minutes or 15 minutes, at

31736 h at a temperature of at least 620 ° C for a period of at least 620 ° C at least 10 minutes, 12 minutes or 15 minutes, or at a temperature of at least 640 ° C for at least 10 minutes, 12 minutes or 15 minutes.

The aforementioned combination of zinc (Zn) and aluminum (Al) in the underlying barrier layer of the present invention can provide the preferred combination of properties discussed above, especially if the atomic ratio Al / Zn is in the range of 0.03 to 0.3, preferably ranging from 0.05 to 0.15. Said atomic ratio Al / Zn may be less than about 1. A preferred combination of properties may also be achieved by using a combination of zinc (Zn) and titanium (Ti) in the substrate barrier layer according to the invention, especially if the atomic ratio Ti / Zn is in the range of from 1 to 10, preferably from 1.5 to 6, and even more preferably in the range of from 2 to 5.

If the coating of the present invention comprises more than one substrate barrier layer, the layers may have the same or substantially the same composition. This can simplify process control and order and store the necessary raw materials.

The combination of the underlying barrier layer of the present invention including zinc (Zn) together with another element X, and the dielectric layer adjacent to the underlying barrier layer and also including zinc (Zn) together with the same other element X, may simplify the oxidation control of said substrate. the substrate barrier layer during heat treatment of the glazing panel of the present invention.

When the same or similar material is used to form the underlying barrier layer to form the top barrier layer of the present invention, the oxidation control of both said barrier layers during heat treatment of the glazing panel of the present invention can be facilitated. In particular, this may be facilitated if one or more of said adjacent dielectric layers comprises a similar material.

31736 h • · ·

The use of similar materials to form more than one layer forming the layered coating of the present invention can facilitate the control of the entire process used to apply the different layers, since it is possible to use similar conditions to form different layers. Furthermore, the use of raw materials of the same composition for applying more than one layer contained in the coating of the present invention can facilitate the storage and ordering of such raw materials on an industrial scale. The use of such raw materials can also ensure good adhesion between the deposited layers and hence good mechanical resistance of the layered coating formed.

Another aspect of the present invention is a method for producing a glazing panel, the characteristics of which are defined in claim 14 below. This method can be used, for example, to produce heat-treated glazing panels used in architecture, automotive glazing, and in particular automotive windshields.

Brief Description of the Drawings

Figure 1 shows a cross-section of a glazing panel according to the present invention prior to bending and heat treatment (for the sake of simplicity, the thicknesses of the glazing panel and the individual layers are not shown in the corresponding proportions).

DETAILED DESCRIPTION OF THE INVENTION

Example 1

The examples below are described with reference to Figure 1. Figure 1 shows a heat-treatable layered coating comprising two silver layers, which is deposited on a glass substrate,

31736 h ····························· The magnetron sputtering was used to form the coating, and the coating had the following structure: ··· ··········

Relationship mark Geometric thickness Atomic ratio Glass base 10 2 millimeters Dielectric base layer comprising: AIN ZnAlOx 11 12 13 60 Á 250 A Al / Zn = 0.1 Background barrier ZnAlOy 14 10R Al / Zn = 0.1 Ag 15 100 Ä ZnAlOy top barrier 16 12R Al / Zn = 0.1 Middle dielectric layer comprising: ZnAlOx 17 750 A Al / Zn = 0.1 Background barrier ZnAlOy 18 7A Al / Zn = 0.1 Ag 19 100 A ZnAlOy top barrier 20 17A Al / Zn = 0.1 Dielectric outer layer comprising: ZnAlOx AIN 21 22 23 185 Ä 85 Á Al / Zn = 0.1

ZnAlOx is a mixed oxide containing zinc (Zn) and aluminum (Al), which in this case was deposited by reactive sputtering, using an alloy or a mixture of zinc (Zn) and aluminum (Al) in the presence of oxygen. Similarly, ZnAlOy barriers were applied by sputtering using an alloy or a mixture of zinc as the raw material.

31736 h * · ································ (Zn) and aluminum (Al), in an argon-enriched oxygen atmosphere to apply a barrier layer that is not completely oxidized.

Alternatively, it was possible to form a mixed oxide layer by sputtering using a mixture of zinc oxide and alumina as a raw material, especially in an argon atmosphere or an argon-enriched oxygen atmosphere.

The oxidation state in all of said (i.e., in the base, middle and outer) dielectric layers including ZnAlOx was not necessarily the same. Similarly, the oxidation state in all said barrier layers comprising ZnAlOy may not be the same. Also, the Al / Zn ratio may not have been the same in all of the above layers; for example, said barrier layers could contain a different Al / Zn ratio than said antireflective dielectric layers, and these antireflective dielectric layers could differ from each other by the Al / Zn ratio.

Each of the top barrier layers protected the corresponding silver layer overlapped from oxidation during the deposition of the ZnAlOx layer overlying the barrier layer, the deposition of said oxide layer being by sputtering. Although further oxidation of these barrier layers may have occurred during the deposition of the oxide layers overlapping them, some of these barrier layers preferably retained an oxide form that was not completely oxidized, so that the layer could serve as a barrier to subsequent heat treatment of the glass sheet.

The glazing panel of this example was intended especially for incorporation into laminated glass, which is used as a windshield of a car and exhibited the following characteristics:

31736 h ··

property Before cooking ¹ After heat treatment ^ TL (illuminant A) 63 percent 76 percent TE (Moon 2 system) 38 percent 42 percent turbidity 0.1 0.25 and -20 (on the coating side) -6 (outside) b ' +3 (on the coating side) -12 (outside) RE (Moon 2 system) 31 percent (on the coating side) 33 percent (outside)

Measured for a monolithic coated glazing panel before it has been heat treated ² Measured after the heat treatment has been carried out for 10 minutes at 650 ° C, after which time the pane has been bent, tempered and laminated with a 2 mm thick glass pane. Clear PVB 0.76 millimeter thick.

The heat treatment in a preferred embodiment caused substantially complete oxidation of all barrier layers, so that the laminated coating after heat treatment had the following structure:

31736 h ··

Relationship mark Geometric thickness Atomic ratio Glass base 10 2 millimeters Dielectric base layer comprising: AIN (partially oxidized) ZnAlOx 11 12 13 60 Á 250 Ä Al / Zn = 0.1 ZnAlOx (oxidized background barrier) 14 10 - 16Ä Al / Zn = 0.1 Ag 15 100 Ä ZnAlOx (oxidized upper barrier) 16 12-20 A Al / Zn = 0.1 Middle dielectric layer comprising: ZnAlOx 17 750 Ä Al / Zn = 0.1 ZnAlOx (oxidized background barrier) 18 7-12 Al / Zn = 0.1 Ag 19 100 Á ZnAlOx (oxidized upper barrier) 20 17 - 28 Nr Al / Zn = 0.1 Dielectric outer layer comprising: ZnAlOx AIN 21 22 23 185 A 85 Á Al / Zn = 0.1

Said (partially oxidized) aluminum nitride (AIN) layers could comprise a mixture of aluminum nitride (AIN) and alumina (Al ₂ O ₃ ), the partial oxidation of AIN taking place in said heat treatment process. These barrier layers did not necessarily have to be completely oxidized and their thickness was dependent to some extent on their degree of oxidation.

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· · · · · · · · • • · • • • · • • • • · • • • • • · · · • • • • • · · • · • • · 9 • • • ···· • · · · · · · · · · ·

Example 2

The laminate applied to the glass sheet in this case had the following structure and properties:

Relationship mark Geometric thickness Atomic ratio Glass base 10 2 millimeters Dielectric base layer comprising: AIN ZnAlOx 11 12 13 100 Ä 200 Ä Al / Zn = 0.1 Background barrier ZnAl 14 7 Á Al / Zn = 0.1 Ag 15 100 Á Upper barrier ZnAl 16 10R Al / Zn = 0.1 Middle dielectric layer comprising: ZnAlOx 17 750 Á Al / Zn = 0.1 Background barrier ZnAl 18 5 Angstrom Al / Zn = 0.1 Ag 19 100 A Upper barrier ZnAl 20 14 Ä Al / Zn = 0.1 Dielectric outer layer comprising: ZnAlOx AIN 21 22 23 185 Á 85 A Al / Zn = 0.1

ZnAlOx is a mixed oxide containing zinc (Zn) and aluminum (Al), which in this case was deposited by reactive sputtering, in which an alloy or a mixture of zinc (Zn) and aluminum (Al) was used in the presence of oxygen. Similarly, ZnAl barriers were deposited by plating

31736 h ······························ by sputtering, in which the alloy or mixture of zinc (Zn) and aluminum (Al) was used as the raw material in a substantially inert, non-oxygen atmosphere.

At least a portion of the top barrier layers 16 and 20 was oxidized during the deposition of the oxide layers overlapping them. However, at least a portion of these barrier layers preferably retained a metal form or at least a form of oxide that is not completely oxidized, so that the layer could serve as a barrier in the subsequent heat treatment of the glass sheet.

The glazing panel of this example was intended especially for incorporation into laminated glass, which is used as a vehicle windshield, and exhibited the following characteristics:

property Before cooking ¹ After heat treatment * TL (illuminant A) 61 percent 77.5 percent TE (Moon 2 system) 36 percent 43 percent turbidity 0.1 0.22 and -18 (on the coating side) -3 (outside) b ' +6 (on the coating side) -7 (outside) RE (Moon 2 system) 30 percent (on the coating side) 35 percent (outside)

Measured for a monolithic glazing with a coating applied before it is heat treated

Measured after heat treatment was carried out for 14 minutes at 625 ° C, after which time the panel was gradually

31736 h bent, tempered and laminated with 2 mm thick glass sheet and 0.76 mm clear PVB foil.

The heat treatment in the preferred embodiment caused substantially complete oxidation of all barrier layers, so that the laminated coating after heat treatment had the following structure:

Relationship mark Geometric thickness Atomic ratio Glass base 10 2 millimeters Dielectric base layer comprising: AIN (partially oxidized) ZnAlOx 11 12 13 100 Ä 200 Ä Al / Zn = 0.1 ZnAlOx (oxidized background barrier) 14 9 - 12Ä Ag 15 100 Ä ZnAlOx (oxidized upper barrier) 16 12 - 16A Al / Zn = 0.1 Middle dielectric layer comprising: ZnAlOx 17 750 Á Al / Zn = 0.1 ZnAlOx (oxidized background barrier) 18 6-9A Al / Zn = 0.1 Ag 19 100 Á ZnAlOx (oxidized upper barrier) 20 17-23 Art Al / Zn = 0.1 Dielectric outer layer comprising: ZnAlOx AIN (partially oxidized) 21 22 23 185 A 85 A Al / Zn = 0.1

31736 h · · I ·························································

Without departing from the scope of the present invention, additional layers may be added above, below, or between said coatings.

In addition to the aforementioned advantageous optical properties obtainable by the present invention, each of the above examples describes the formation of a coating that can be electrically heated, for example in electrically heated car windows, which is heated by means of suitably positioned electrical connectors to secure demisting and / or de-icing function.

The chromaticity coordinates of the glass panes of the above examples are particularly suitable for use in the production of automotive windshields, since when the glass is mounted to the car body at an angle, these coordinates provide a neutral or slightly blue appearance when reflected by incident light. For other uses, such as when it is desired that the automotive glass has a slightly green appearance, or when using the glass of the present invention in architecture where other coloring of the glass is desired, the color of the glass of the present invention may be adjusted in a manner known in the art, and which comprises adjusting the thickness of the dielectric layers and / or the infrared reflecting layers.

The TL value of the glazing panel of the present invention may be adjusted to suit the desired use. For example:

- if the glazing panel of the present invention is to be used as a car windshield on the European market, the TL value can be selected to be greater than 75 percent (as required by European Union regulations);

if the glazing panel of the present invention is to be used as a car windshield in the United States market, the TL value may be selected to be greater than 70 percent (as required by United States regulations);

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- if the glazing panel of the present invention is to be used as a windshield of a car, the TL value may be selected to be greater than 70 percent (as required by European Union regulations);

- if the glazing panel of the present invention is to be used as a rear side window or a car rear window, the TL »value may be chosen to be in the range of 30 percent to 70 percent *

For example, the above TL adjustments can be achieved:

by adjusting the thickness of the layers contained in the layered coating according to the invention, in particular by adjusting the thickness of the dielectric layers and / or the layers reflecting infrared radiation;

combining the layered coating of the present invention with a tinned glass substrate;

combining the layered coating according to the invention with tinned PVB or other laminating materials;

Claims (14)

PATENT CLAIMS A glazing panel carrying a layered coating comprising a sequence comprising at least: glass backing material; a base antireflective layer; a substrate barrier layer; a reflective layer reflecting infrared radiation; a top barrier layer; and an outer antireflection layer, characterized in that said substrate barrier layer comprises a mixture of zinc (Zn) and at least one other element X, wherein the atomic ratio X / Zn in said substrate barrier layer is equal to or greater than 0.03 and X represents one or a plurality of elements selected from the group consisting of elements of groups 3a, 3b, 4a, 4b, 5a, 5b, 6b, 7b of the Periodic Table of the Elements. The glazing panel of claim 1 comprising a sequence comprising at least: glass backing material; a base antireflective layer; a substrate barrier layer; a reflective layer reflecting infrared radiation; a top barrier layer; a medium antireflective layer backing barrier layer; a reflective layer reflecting infrared radiation; a top barrier layer; an outer antireflection layer, characterized in that at least one of said substrate barrier layers comprises a mixture of zinc (Zn) and at least one other element X, wherein the atomic ratio X / Zn in said substrate barrier layer is equal to or 31736 h ······································· as 0.03 and X represents one or more elements selected from the group consisting of elements of group 3a, 3b, 4a, 4b, 5a, 5b, 6b, 7b of the Periodic Table of the Elements. Glazing panel according to claim 1 or 2, characterized in that said glazing panel is a heat-treatable or substantially non-cloudy heat-treated glass sheet. Glazing panel according to any one of claims 1 to 3, characterized in that said or at least one of said substrate barrier layers comprises a mixture of zinc (Zn) and aluminum (Al) in an atomic ratio Al / Zn of at least 0.03. The glazing panel of claim 4, wherein said or at least one of said underlying barrier layers comprises a mixture of zinc (Zn) and aluminum (Al) in an Al / Zn atomic ratio ranging from 0.03 to 0.3. Glazing panel according to any one of claims 1 to 3, characterized in that said or at least one of said substrate barrier layers comprises a mixture of zinc (Zn) and titanium (Ti) in an atomic Ti / Zn ratio of at least 0.03. The glazing panel of claim 6, wherein said or at least one of said underlying barrier layers comprises a mixture of zinc (Zn) and titanium (Ti) in an atomic Ti / Zn ratio ranging from 1 to 10. Glazing panel according to any one of claims 1 to 7, characterized in that said atomic ratio X / Zn is equal to or less than 5. 31736 h • S ···································· 99 9999 99 99 99 999 Glazing panel according to any one of claims 1 to 8, characterized in that said or at least one of said substrate barrier layers is applied in the form of a metal or in a substantially metallic form. Glazing panel according to any one of claims 1 to 9, characterized in that said or at least one of said underlying barrier layers has a geometric thickness equal to or less than 50 A. Glazing panel according to any one of claims 1 to 10, characterized in that said or at least one of said antireflective layers comprises an oxide layer comprising a mixture of zinc and another element X contained in said or one of said underlying barrier layers. Glazing panel according to claim 11, characterized in that said or at least one of said antireflective layers comprises an oxide layer comprising a mixture of zinc and another element X in an atomic ratio X / Zn substantially identical to the atomic ratio X / Zn in said or in one of said underlying barrier layers. Glazing panel according to any one of claims 1 to 12, characterized in that at least one top barrier layer comprises a mixture of zinc (Zn) and one or more other elements selected from the group consisting of elements of group 3a, 3b, 4a, 4b, 5a, 5b, 6b, 7b of the Periodic Table of the Elements. 14. A method of making a glazing panel whose haze is less than about 0.5, characterized in that it comprises the step of subjecting the glazing panel 31736 h • · · · · · · · • · • · • · • • • • · e • • · • • · · · • · • ··· · • • • · • · · • • • • • · • · ···· · · · · · · ·· · according to any one of claims 1 to 13 of a heat treatment process at a temperature of at least 570 ° C.