Glazing panel

Description of the invention

The present invention relates to a glazing panel having a coating unit and a method of manufacturing the same.

The invention relates in particular, but not exclusively, to solar control glazing panels which are intended to be subjected to a heat treatment subsequent to the application of the solar control filter. EP 233003A discloses a glazing panel having a sputter-coated optical filter of the following structure: glass substrate / SnO2 primary dielectric / first metallic barrier of Al, Ti, Zn, Zr or Ta / Ag / second metallic barrier of Al, Ti, Zn , Zr or Ta / SnO2 surface dielectric. This optical filter is designed to block a significant portion of the incident radiation in the infrared portion of the spectrum while passing a significant portion of the incident radiation in the visible portion of the spectrum. In this way, this filter acts to reduce the thermal effect of incident sunlight while ensuring good visibility through such glazing, and is particularly suitable for car windows.

In this type of structure, the Ag layer acts to reflect incident infrared radiation, and in order to fulfill this role it must be kept in the form of metallic silver rather than in the form of silver oxide and must not be contaminated by adjacent layers. The dielectric layers which include the Ag layer are intended to reduce the reflection of the visible part of the spectrum which would otherwise be caused by the Ag layer itself. The second barrier serves to prevent oxidation of the Ag layer during sputtering of the upper dielectric SnO2 layer in an oxidizing atmosphere; this barrier is at least partially oxidized during the process. The main task of the first barrier layer is to prevent oxidation of the silver layer during the heat treatment of this coating (i.e. during bending and / or toughening) of the glazing panel due to the fact that it is this layer that oxidizes itself rather than allowing oxygen to pass through it into the Ag layer. This oxidation of the barrier layer during the heat treatment increases the TL in the glazing panel.

EP 792847A discloses a heat treatable solar control glazing panel which is based on the same principle and has the following structure: glass substrate / ZnO dielectric / Zn / Ag barrier / Zn barrier / ZnO dielectric / Zn / Ag barrier / Zn barrier / ZnO dielectric. The ZnO barriers located beneath each of the Ag layers are designed to completely oxidize during the heat treatment and serve to protect the Ag layers from oxidation. As is well known in the art, a structure having instead of a single Ag layer rather two separated Ag layers increases the selectivity of this filter.

EP 275474A discloses a heat treatable solar radiation control panel having the following structure: glass substrate / zinc tin dielectric / Ti / Ag barrier / Ti barrier / zinc tin dielectric. Ti barriers are generally preferred in these types of heat treatable structures because of their high affinity for oxygen and the relative ease with which they can be oxidized to form titanium oxide. EP 464789 discloses a panel with the following layer arrangement: glass / Al doped ZnO / Ag / Al-doped Zn barrier layer / Al doped ZnO, the Al / (Al + Zn) ratio being 3 atomic%. ZnO is doped with at least one element selected from the group consisting of Al, Si, B, Ti, Sn, Mg and Cr in an amount of no more than 10 atom%. 10 atomic% of X / (X + Zn) is equivalent to a maximum X / Zn atomic ratio of 0.11 which is contrary to the panel of the present invention for which the X / Zn atomic ratio is claimed to be greater than or equal to 0.12 . According to the information contained in EP 464789, it is necessary to lower the internal stress of ZnO in order to obtain a coating with low emissivity and increased durability. The document also indicates that doping of ZnO with Al, Si, B, Ti, Sn, Mg or Cr in an amount of up to 10 atomic% lowers or eliminates the appearance of white haze that has been observed in known ZnO-containing coatings.

The cited document does not disclose an atomic X / Zn ratio greater than 0.11 and furthermore teaches that the given value is the maximum allowable value.

EP 751099 discloses the following layer system: glass / Al containing additional metal / Pd-doped Ag / barrier layer / ZnO containing additional metal, the additional metal being at least one metal selected from the group consisting of Sn, Al, Cr, Ti, Si, B , Mg and Ga. The ratio (additional metal) / (additional metal + Zn) in the doped ZnO is 1-10 atomic%.

This document explains that increasing the additional metal content above 10% lowers the resistance to moisture and lowers the crystallization ability of ZnO, which lowers its Ag compatibility. Moreover, the cited document does not disclose the atomic ratio X / Zn of value

PL 199 409 B1 higher than 0.11 and in fact instructs not to increase the content of impurities above this value. The document also does not disclose doped dielectric layers

ZnO, which is, among others the essence of the present invention.

Moreover, none of the documents EP 464789, EP 751099 mentions the heat stability of the coatings and their properties after heat treatment. It is not disclosed in the prior art and not even suggested that additional advantageous features of the system such as depositionability and controllability may be obtained.

The cited documents expressly do not mention the loss of some features of the system when increasing the X / Zn doping index above 0.11, while the panel according to the present invention has this higher value (above 0.12). H1 EP 718250 discloses a coating system whose properties remain unchanged after heat treatment. This publication does not disclose or even suggest the use of an oxide-containing mixed oxide layer that is a mixture of Zn and at least one additional material X that characterizes the present invention.

The present invention relates to a glazing panel having a coating unit comprising at least in a suitable order:

a glass substrate, a base antireflective layer, an infrared reflecting layer, and a surface antireflective layer, characterized in that at least one of the antireflective layers comprises at least one mixed oxide layer comprising an oxide that is a mixture of Zn and at least one additional material X. in which the atomic ratio X / Zn is greater than or equal to 0.12, and wherein X is one or more materials selected from the group consisting of elements in Groups 2a, 3a, 5a, 4b, 5b, 6b of the Periodic Table of the Elements.

The glazing panel contains, in proper order, at least: a glass substrate, a base antireflective layer, an infrared reflecting layer, a middle antireflective layer, an infrared reflective layer, and a surface antireflective layer, preferably at least one of the antireflective layers comprises at least one mixed oxide layer comprising an oxide that is a mixture of Zn and at least one additional material X, wherein the atomic ratio X / Zn is greater than or equal to 0.12, and wherein X is one or more materials selected from the group consisting of elements in Groups 2a, 3a, 5a, 4b, 5b, 6b of the Periodic Table of the Elements.

Preferably, X is one or more materials selected from the group consisting of Ti and Al.

Preferably, the glazing panel is a heat treatable panel or a heat treated haze free panel.

Preferably, at least one mixed oxide layer has a geometric thickness greater than or equal to 5Ί0⁹γπ (50 A).

Preferably, each of the base antireflection layer and the surface antireflection layer comprises at least one mixed oxide layer comprising an oxide that is a mixture of Zn and at least one additional material X, in which the atomic ratio X / Zn is greater than or equal to 0.12, and wherein X it is one or more materials selected from the group consisting of elements in Groups 2a, 3a, 5a, 4b, 5b, 6b of the Periodic Table of the Elements.

Preferably, the middle anti-reflective layer comprises at least one mixed oxide layer comprising an oxide that is a mixture of Zn and at least one additional material X, wherein the atomic ratio X / Zn is greater than or equal to 0.12, and wherein X is one or more selected materials. from the group consisting of elements from Groups 2a, 3a, 5a, 4b, 5b, 6b of the Periodic Table of the Elements.

Preferably, the atomic ratio X / Zn in the mixed oxide layer is in the range 0.12 to 1, more preferably 0.15 to 0.6.

Particularly preferably, the X / Zn atomic ratio of the mixed oxide layer is in the range 0.2 to 0.5.

PL 199 409 B1

Preferably, the base anti / reflective layer comprises a layer adjacent to the substrate comprising aluminum nitride or silicon nitride, or a mixture thereof, and an overlying layer comprising a mixed oxide layer.

Preferably, the surface anti-reflective layer comprises a mixed oxide layer and an overlying layer containing aluminum nitride or silicon nitride, or a mixture thereof.

Preferably, the glazing panel is a heat treatable panel or a heat treated haze free panel, whereby heat treatment of the heat treatable glazing panel to form a haze free heat treated glazing panel increases the TL value of the glazing panel by at least 2.5%.

Preferably, the atomic ratio X / Zn is less than or equal to 5.

The invention also relates to a method for producing the above-defined glazing panel with a haze of less than 0.5, characterized in that it comprises a step in which the glazing panel is heat-treated at a temperature of at least 570 ° C.

The inclusion of at least one anti-reflective layer containing a mixture of Zn and one of the specific additional materials provides an advantageous combination of properties. This anti-reflection layer not only plays a major role in preventing excessive reflection of the visible part of the spectrum but also has to, for example, be compatible with the other layers in this coating unit, it has to be mechanically and chemically resistant, and it has to be suitable for production on a scale. industrial.

Any suitable methods or combination of methods may be used to apply the coating layers. For example, vaporization (thermal or - electron radiation), liquid pyrolysis, chemical vapor deposition, vacuum deposition and sputtering, especially magnetron sputtering, the latter method being particularly preferred. Different layers of this coating unit may be deposited by different techniques.

The anti-reflective layer of the invention may provide an advantageous combination of features such as:

- heat resistance when the glazing panel is heated, for example during toughening and / or bending. It is noteworthy that the use of the present invention can reduce the degradation of the infrared reflecting layer when compared with similar structures used, for example, with known ZnO or SnO2 containing anti-reflection layers.

- ease and controllability of the deposition: the anti-reflection layer in the panel according to the invention can be deposited much easier and with more control than, for example, Al2O3 or SiO2. While Al2O3 and SiO2 show a good degree of heat stability, they are difficult to deposit using conventional sputtering techniques.

- mechanical resistance: the anti-reflection layer in the panel according to the invention can be used without first estimating the mechanical resistance of the entire coating. In particular, it may perform well in the compactor test where the glazing panel is used in a laminated structure.

- Ag compatibility: the crystallization of the Ag layer affects its optical properties. A clean ZnO layer adjacent to the Ag layer can lead to overcrystallization of this Ag and to haze problems in this coating, especially when the coating is heat treated. However, when the anti-reflective layer does not contain ZnO, insufficient recrystallization of the Ag layer can be obtained, which in turn affects the level of infrared radiation reflection and the level of electrical conductivity in this coating, which are below the optimal achievable values. The present invention can be used to obtain advantageous crystallization with a sufficient degree to ensure good IR reflectivity while avoiding excessive haze. In particular, it can provide a favorable crystallization comparable to the anti-reflective layer composed of TiO2. One possible explanation for this may be that the presence of material X in the zinc oxide structure may reduce crystal grain growth in the mixed oxide layer, especially in the direction perpendicular to the substrate. This can result in the formation of smaller crystals, obtaining a more amorphous structure, which reduces the diffusion that would otherwise occur at the crystal grain boundaries.

- production cycle time: an oxide layer which is a mixture of Zn and at least one specific additional material, especially when the additional material is Ti, Ta, Zr, Nb, Bi or a mixture of these metals, will generally have a higher refractive index than anti-reflective layers made from ZnO or SnO2, for example, which are commonly used

In similar structures, and moreover, it will be able to be deposited even faster than known anti-reflective layers with a relatively high refractive index, for example TiO2.

Consequently, this may allow a significant improvement in the time of the production cycle to be obtained.

good selectivity: a higher refractive index may furthermore facilitate an increase in the selectivity of this coating unit, especially when the additional material is Ti, Ta, Zr, Nb, Bi or a mixture of these metals.

The use of the anti-reflection layer as a surface anti-reflection layer or as part of the surface anti-reflection layer, and especially as a layer subjected to the atmosphere, can provide good chemical and mechanical resistance. Moreover, it can provide good compatibility with a thin laminating layer, for example a thin PVB layer, if the glazing panel of the invention is to be laminated to form, for example, an automotive windshield or other laminated glazing panel.

The advantageous properties of the anti-reflective layer in the panel according to the invention may not be obtained if the atomic ratio X / Zn is below a certain minimum, for example, if material X is present in Zn as impurities or if the atomic ratio X / Zn is not high enough. . The atomic ratio X / Zn may be less than about 10; it may be less than or equal to about 5 or about 4 or about 3. This may provide a sufficient amount of Zn in the anti-reflective layer to provide favorable properties.

The infrared reflecting material may be silver or a silver alloy, for example a silver alloy containing one or more of Pd, Au and Cu, as an additive material. Such additive material may be present in the silver alloy in an atomic ratio based on the total amount of silver and the additional metal of 0.3 to 10%, preferably 0.3 to 5%, and more preferably, especially when the additive material is Pd. , 3 to 2%.

One or more of the anti-reflective layers may include an oxide, nitride, carbide, or a mixture thereof. For example, the anti-reflection layer may include:

• an oxide of one or more of Zn, Ti, Sn, Si, Al, Ta or Zr; zinc oxide containing Al, Ga, Si or Sn or indium oxide containing Sn;

• a nitride of one or more of Si, Al and B, or a mixture (including double nitride) of a Zr nitride or a Ti nitride with one of the above-mentioned nitrides;

• a double compound, for example SiOxCy, SiOxNy, SiAlxNy or SiAlxOyNz.

The anti-reflective layer may be a single layer or it may include two or more layers of different compositions. Zinc oxide, preferably zinc oxide containing at least one of Sn, Cr, Si, B, Mg, In, Ga and preferably Al and / or Ti, is particularly preferred as the use of these materials can facilitate the permanent formation of an adjacent high infrared reflecting layer. crystallization.

The advantageous combination of the properties achieved by the anti-reflection layer in the panel according to the invention can also be used in a coating unit having two, or even more than two, separate infrared reflecting layers.

In order to obtain a glazing panel with a selectivity greater than 1.5 or 1.7, multiple, separate, infrared reflecting layers may be used.

Particularly advantageous properties can be obtained if the additive material X comprises:

- essentially Ti,

- Ti and one or more additional materials selected from a specific group of materials, for example, Ti and Al,

- basically Al,

- Al and one or more additional materials selected from a specific group of materials.

Thus, the present invention can provide a combination of properties with the particular advantages of providing heat treatable glazing panels and heat treated glazing panels. However, the invention can also provide untreated glazing panels.

The term "heat treatable glazing panel" as used in this description means that the glazing panel has a coating unit adapted to undergo bending and / or heat toughening and / or heat curing and / or other heat treatments without the occurrence of haze so treated. glazing panels exceeding 0.5, preferably with no haze exceeding 0.3.

PL 199 409 B1

The term "heat treated glazing panel without fogging" (or "substantially no fogging") as used in this specification means a glazing panel having a coating unit that has been bent and / or heat toughened and / or heat cured and / or other heat treatments already when the coating device is deposited thereon, it has a haze not exceeding a value of 0.5, preferably not exceeding a value of 0.3. Such heat treatment may involve heating or exposing the glazing panel having the coating unit to a temperature greater than about 560 ° C, for example, between 560 ° C and 700 ° C in the atmosphere. Other such heat treatments may be: sintering ceramics or enamels, vacuum sealing a double-glazed unit, and calcining (baking) a wet-applied low-reflecting coating or anti-glare coating.

The heat treatment, especially when it is bending and / or heat toughening and / or heat setting operation, may be carried out at a temperature of: at least 600 ° C for at least 10 minutes, 12 minutes, or 15 minutes, at least 620 ° C for at least 10 minutes, 12 minutes, or 15 minutes, or at least 640 ° C for at least 10 minutes, 12 minutes, or 15 minutes.

Arranging the thickness of the mixed oxide layer so that it has a thickness of at least

5-10^-9m (50 A) can supply enough of it to obtain a valuable and noteworthy result. The geometric thickness of the mixed oxide layer in the panel according to the invention may be at least 840⁹m (80 A), 10^-8m (100 A), 1.240⁸m (120 A), 1.440⁸m (140 A) or 1,640⁸m (160 A).

An oxide layer which is a mixture of Zn and at least one specific additional material may be used to impart advantageous properties to one, more than one, or preferably all of the anti-reflective layers in the coating unit. The use of this mixture in all of the anti-reflective layers belonging to this coating unit can greatly simplify the process of controlling and ordering and storing the necessary targets. If more than one of the anti-reflective layers comprises an oxide layer that is a mixture of Zn and at least one specific additional material, such oxide layers may have the same or substantially the same compositions.

A particularly advantageous combination of the properties discussed above can be obtained when the atomic ratio X / Zn is in the range 0.12 to 1, preferably in the range 0.15 to 0.6 and most preferably in the range 0.2 to 0.5.

The oxide layer may be compatible for use with the anti-reflection layer, and may preferably be combined with a layer comprising aluminum nitride or silicon nitride, or a mixture thereof, into one or more anti-reflection layers. This can provide particularly good thermal stability, especially when such a combination is used in the base and / or surface anti-reflection layer.

The filter assembly may include one or more barrier layers below and / or above the infrared reflecting layer as is well known in the art. Barrier layers made of, for example, one or more of the following materials may be used: Ti, Zn, Ta, Cr, "stainless steel", Zr, Ni, NiCr, ZnTi, NiTi, and ZnAl. Such barrier layers can be deposited, for example, as metallic layers or as suboxides (i.e. partially oxidized layers). Alternatively, nitride barrier layers can also be used.

One or more of such barrier layers may comprise the same materials as the mixed oxide layer, and in particular the adherent mixed oxide layer.

This can greatly facilitate the management of the plates and the control of the deposition conditions, and in a later case it can ensure good adhesion between the layers and therefore good mechanical strength of this coating unit.

The heat treatment may increase the TL of the glazing panel of the invention. Such an increase in the TL value can be advantageous while ensuring that the TL value for this glazing panel is high enough for use as a vehicle windshield. The TL value may increase under absolute conditions during heat treatment, for example, by more than about 2.5%, more than about 3%, more than about 5%, more than about 8%, or more than about 10%.

According to another aspect, the present invention provides a method of manufacturing a glazing panel. Such a method can be used to manufacture, for example, heat-treated architectural glazing panels, vehicle glazing, and in particular, car windows.

Embodiments of the present invention will now be described with reference to Fig. 1, which shows a cross-section through a glazing panel prior to its bending and toughening operation.

(For ease of presentation, the relative thicknesses of the glazing panel and the coating layers are not shown to scale).

Example 1

Figure 1 shows a heat treatable coating comprising a double Ag layer deposited on a glass substrate by magnetron sputtering and having the following structure in the appropriate order:

<td></td><td>Referention number</td><td>Geometric thickness</td><td>Atomic relations</td>

<td>Subsoil glass</td><td> 10</td><td> 2·10^-3 m (2 mm)</td><td></td>

<td>Basic dielectric containing: ZnTiOx</td><td> 11 12</td><td> 2,8·10^-8 m (280 A)</td><td>Ti / Zn = 0.25</td>

<td>ZnTiOy lower barrier layer</td><td> 14</td><td> 1,5·10^-9 m (15 A)</td><td>Ti / Zn = 2.5</td>

<td>Ag</td><td> 15</td><td> 10^-8 m (100 A)</td><td></td>

<td>Upper barrier layer Ti</td><td> 16</td><td> 2·10^-9 m (20 A)</td><td></td>

<td>Middle dielectric containing: ZnTiOx</td><td> 17</td><td> 6,8·10^-8 m (680 A)</td><td>Ti / Zn = 0.25</td>

<td>ZnTiOy lower barrier layer</td><td> 18</td><td> 10^-9 m (10 A)</td><td>Ti / Zn = 2.5</td>

<td>Ag</td><td> 19</td><td> 10^-8 m (100 A)</td><td></td>

<td>Upper barrier layer Ti</td><td> 20</td><td> 2·10^-9 m (20 A)</td><td></td>

<td>A surface dielectric containing: ZnTiOx</td><td> 21 22</td><td> 2,4·10^-8 m (240 A)</td><td>Ti / Zn = 0.25</td>

wherein ZnTiO x is a mixed oxide containing Zn and Ti deposited in this embodiment by reactive sputtering from a target which is an alloy or mixture of Zn and Ti in the presence of oxygen. The ZnTiOy barrier layers are likewise deposited by sputtering a target which is an alloy or mixture of Zn and Ti in an argon-enriched oxygen-containing atmosphere to deposit a barrier layer that is not completely oxidized.

Alternatively, the mixed oxide layer may be formed by sputtering a target which is a mixture of zinc oxide and an oxide of material X, especially in an atmosphere containing argon gas or argon enriched oxygen.

The oxidation state in each of the base, middle and surface ZnTiO x dielectric layers need not necessarily be the same. Likewise, the oxidation state in each of the ZnTiOy barrier layers need not be the same. However, the Ti / Zn ratio need not be the same for all layers; for example, the barrier layers may have a different Ti / Zn ratio than the dielectric anti-reflection layers, and the individual dielectric anti-reflection layers may also have different Ti / Zn ratio values.

Each upper barrier layer protects the underlying silver layer from oxidation during the sputter deposition of the underlying ZnTiO x oxide layer. While further oxidation of these barrier layers may occur during the deposition of the oxide layers thereon, some of the barrier layers preferably remain as oxide which is not fully oxidized to provide a barrier to subsequent heat treatment of the glazing panel.

This particular glazing panel is designed to be incorporated into a laminated automotive windshield and exhibits the following properties:

PL 199 409 B1

<td>Property</td><td>Before heat treatment ^{Note 1}</td><td>After heat treatment ^{Note 2}</td>

<td>TL (Illuminant A)</td><td> 64%</td><td> 77%</td>

<td>TE (Moon System 2)</td><td> 39%</td><td> 40%</td>

<td>Haze</td><td> 0,1</td><td> 0,28</td>

<td>and*</td><td>-12 (coated side)</td><td>-3 (external)</td>

<td>b *</td><td>+ 4 (coated side)</td><td>-8 (external)</td>

<td>RE (Moon System 2)</td><td>33% (coated side)</td><td>34% (external)</td>

Note 1: Measured for monolithic glazing panel with coating prior to heat treatment

Note 2: Measured after heat treatment at 650 ° C for 10 minutes followed by folding and toughening and laminating with a 2 × 10 light glass sheet^-3 m (2 mm) and with a bright PVB with a thickness of 7.6 × 10^-4 m (0.76 mm)

The heat treatment preferably causes substantially complete oxidation of all barrier layers such that the structure of this coating unit after heat treatment is as follows:

<td></td><td>Referention number</td><td>Geometric thickness</td><td>Atomic relations</td>

<td>Glass substrate</td><td> 10</td><td> 2·10'³ m (2 mm)</td><td></td>

<td>Basic dielectric containing: ZnTiOx</td><td> 11 12</td><td> 2,8·10'⁸ m (280 A)</td><td>Ti / Zn = 0.25</td>

<td>ZnTiOx (oxidized lower barrier layer)</td><td> 14</td><td> 2,2·10'⁹ m - 2.8-10^-9 m (22 A - 28 A)</td><td>Ti / Zn = 2.5</td>

<td>Ag</td><td> 15</td><td> 10'⁸ m (100 A)</td><td></td>

<td>TiOx (oxidized upper barrier layer)</td><td> 16</td><td> 3·10^-9 m - 4-10 '⁹ m (30 A - 40 A)</td><td></td>

<td>Middle dielectric containing: ZnTiOx</td><td> 17</td><td> 6,8·10'⁸ m (680 A)</td><td>Ti / Zn = 0.25</td>

<td>ZnTiOx (oxidized lower barrier layer)</td><td> 18</td><td> 1,5·10^-9 m - 2-10 '⁹ m (15 A - 20 A)</td><td>Ti / Zn = 2.5</td>

<td>Ag</td><td> 19</td><td> 10'⁸ m (100 A)</td><td></td>

<td>TiOx (oxidized upper barrier layer)</td><td> 20</td><td> 3·10^-9 m - 4-10 '⁹ m (30 A - 40 A)</td><td></td>

<td>A surface dielectric containing: ZnTiOx</td><td> 21 22</td><td> 2,4·10'⁸ m (240 A)</td><td>Ti / Zn = 0.25</td>

The TiOx bottom barrier layers may be partially oxidized or they may be fully oxidized to TiO2 depending on the heat treatment conditions that the glazing panel is subjected to.

Example 2

Example 2 is similar to Example 1 except that ZnAlOx was used as the anti-reflective layers herein. The coating assembly and properties of Example 2 are shown below:

<td></td><td>Referention number</td><td>Geometric thickness</td><td>Atomic relations</td>

<td>Glass substrate</td><td> 10</td><td> 2·10'³ m (2 mm)</td><td></td>

<td>Basic dielectric containing: ZnAlOx</td><td> 11 12</td><td> 3,15·10^-8 m (315 A)</td><td>Al / Zn = 0.4</td>

PL 199 409 B1

<td>The lower Ti barrier layer</td><td> 14</td><td> 10^-9 m (10 A)</td><td></td>

<td>Ag</td><td> 15</td><td> 10^-8 m (100 A)</td><td></td>

<td>Upper barrier layer Ti</td><td> 16</td><td> 2-10^-9 m (20 A)</td><td></td>

<td>Middle dielectric containing: ZnAlOx</td><td> 17</td><td> 7,6-10^-8 m (760 A)</td><td>Al / Zn = 0.4</td>

<td>The lower Ti barrier layer</td><td> 18</td><td> 8-10^-10 m (8 A)</td><td></td>

<td>Ag</td><td> 19</td><td> 10^-8 m (100 A)</td><td></td>

<td>Upper barrier layer Ti</td><td> 20</td><td> 2-10^-9 m (20 A)</td><td></td>

<td>A surface dielectric containing: ZnAlOx</td><td> 21 22</td><td> 2,7-10^-8 m (270 A)</td><td>Al / Zn = 0.4</td>

wherein ZnAlOx is a mixed oxide containing Zn and Al deposited in this embodiment by reactive sputtering from a target which is an alloy or mixture of Zn and Al in the presence of oxygen. The Ti barrier layers are deposited by sputtering a titanium target in a substantially inert, oxygen-free atmosphere.

At least a portion of the upper barrier layers 16, 20 are oxidized during the deposition of the underlying oxide layers. Nevertheless, some of these barrier layers preferably remain in metallic form, or at least in the form of an oxide that is not fully oxidized to provide a barrier to the subsequent heat treatment of the glazing panel.

This particular glazing panel is designed to be incorporated into a laminated automotive windshield and exhibits the following properties:

<td>Property</td><td>Before heat treatment ^{Note 1}</td><td>After heat treatment ^{Note 2}</td>

<td>TL (Illuminant A)</td><td> 61%</td><td> 76%</td>

<td>TE (Moon System 2)</td><td> 36%</td><td> 43%</td>

<td>Haze</td><td> 0,1</td><td> 0,29</td>

<td>and*</td><td>-17 (coated side)</td><td>-4 (external)</td>

<td>b *</td><td>+ 6 (coated side)</td><td>-9 (external)</td>

<td>RE (Moon System 2)</td><td>30% (coated side)</td><td>32% (external)</td>

Note 1: Measured for monolithic glazing panel with coating prior to heat treatment.

Note 2: Measured after heat treatment at 625 ° C for 14 minutes followed by bending and toughening and laminating with a 2 × 10 light glass sheet^-3 m (2 mm) and with a bright PVB with a thickness of 7.6 × 10^-4 m (0.76 mm).

The heat treatment preferably causes substantially complete oxidation of all barrier layers such that the structure of this coating unit after heat treatment is as follows:

<td></td><td>Referention number</td><td>Geometric thickness</td><td>Atomic relations</td>

<td>Glass substrate</td><td> 10</td><td> 2-10^-3 m (2 mm)</td><td></td>

<td>Basic dielectric containing: ZnAlOx</td><td> 11 12</td><td> 3,15-10^-8 m (315 A)</td><td>Al / Zn = 0.4</td>

<td>TiOx (oxidized lower barrier layer)</td><td> 14</td><td> 1,5-10^-9 m - 2-10^-9 m (15 A - 20 A)</td><td></td>

<td>Ag</td><td> 15</td><td> 10^-8 m (100 A)</td><td></td>

<td>TiOx (oxidized upper barrier layer)</td><td> 16</td><td> 3-10^-9 m - 4-10^-9 m (30 A - 40 A)</td><td></td>

<td>Middle dielectric containing: ZnAlOx</td><td> 17</td><td> 7, 6-10^-8 m (760 A)</td><td>Al / Zn = 0.4</td>

PL 199 409 B1

<td>TiOx (oxidized lower barrier layer)</td><td> 18</td><td> 1,2·10^-9 m - 1.5 · 10^-9 m (12 A - 15 A)</td><td></td>

<td>Ag</td><td> 19</td><td> 10^-8 m (100 A)</td><td></td>

<td>TiOx (oxidized upper barrier layer)</td><td> 20</td><td> 3·10^-9 m - 4 · 10^-9 m (30 A - 40 A)</td><td></td>

<td>A surface dielectric containing: ZnAlOx</td><td> 21 22</td><td> 2,7·10^-8 m (270 A)</td><td>Al / Zn = 0.4</td>

In an alternative embodiment of the invention, the base dielectric layer of Example 2 may comprise a first ZnAlOx layer with an Al / Zn atomic ratio ranging from 0.12 to 1, and an upper ZnAlOx layer with an Al / Zn atomic ratio lower than the former. layer, for example equal to 0.1.

Additional layers may be introduced above, below, or between the thin layer coating unit arrangement as desired without departing from the scope of the present invention.

In addition to the advantageous optical properties that can be obtained, each of the examples provides a coating that can be electrically heated, for example, in electrically heated car windows to provide steam-bleeding and / or defrosting functions with the addition of appropriately positioned electrical connectors.

The color coordinates of these examples are particularly suitable for car windows as they give a neutral or slightly blue reflection appearance when the glass is mounted at an angle to the car body. For other applications, for example, if a slightly green appearance is desired for car windows or in the case of architectural applications where a different color is desired, the color in reflection can be adjusted as known in the art by adjusting the thickness of the dielectric layers and / or the layers. silver.

The TL value of the glazing panel can be adjusted according to the desired application. E.g:

- if the glazing panel is to be used as a car windshield for the European market, it is possible to select a TL value higher than 75% (which is required by European regulations).

- if the glazing panel is to be used as a car windshield for the American market, the TL value higher than 70% can be selected (which is required by the American regulations).

- if the glazing panel is to be used as a front position lamp for the vehicle, it is possible to adjust the TL value higher than 70% (as required by European regulations).

- if the glazing panel is to be used as a rear position lamp for a vehicle or a car rear windshield, a TL value of about 30% to 70% can be selected.

Such TL value matching can be achieved, for example:

by adjusting the thickness of the layers of the coating unit, in particular the thickness of the dielectric and / or infrared reflecting layers.

- by bonding the coating unit to a colored glass substrate.

- by combining the coating unit with colored PVB or other laminating materials.

Terminology

Unless otherwise indicated in the description from context, the following terms have the following meanings in this description:

<td>and*</td><td></td><td>color coordinate measured on the CIELab scale with normal incidence of rays</td>

<td>Ag</td><td>silver</td><td></td>

<td>Al</td><td>aluminum</td><td></td>

<td>Al2O3</td><td>alumina</td><td></td>

<td>AlN</td><td>aluminum nitride</td><td></td>

<td>b *</td><td></td><td>color coordinate measured on the CIELab scale with normal incidence of rays</td>

<td>Bi</td><td>bismuth</td><td></td>

<td>Cr</td><td>chrome</td><td></td>

PL 199 409 B1

<td>haze</td><td></td><td>Percentage of transmitted light that passes through the sample deviation from the incident beam by forward scattering as measured by ASTM Designation D 1003-61 (reapproved in 1988)</td>

<td colspan="2">material reflecting infrared radiation</td><td>a material that has a reflectance higher than that of the soda-lime glass in the wavelength range of 7.810 '⁷ιτι (780 nm) to 5 10^-5 m (50 microns)</td>

<td>Nb</td><td>niobium</td><td></td>

<td>NiCr</td><td></td><td>an alloy or mixture containing nickel and chromium</td>

<td>NiTi</td><td></td><td>an alloy or mixture containing nickel and titanium</td>

<td>RE</td><td>energetic reflection</td><td>solar radiation flux (light and non-light) reflected from the ground as a percentage of the incident solar radiation flux</td>

<td>selectivity</td><td></td><td>the ratio of light transmittance to energy transmittance, i.e. TL / TE</td>

<td>SiO2</td><td>silicon oxide</td><td></td>

<td>Si3N4</td><td>silicon nitride</td><td></td>

<td>SnO2</td><td>tin oxide</td><td></td>

<td>Yeah</td><td>tantalum</td><td></td>

<td>THESE</td><td>transmittance energetic</td><td>solar radiation flux (light and non-light) transmitted through the substrate as a percentage of the incident solar radiation flux</td>

<td>Ti</td><td>titanium</td><td></td>

<td>TL</td><td>transmittance luminous</td><td>solar radiation flux passed through the substrate as a percentage of the incident solar radiation flux</td>

<td>Zn</td><td>zinc</td><td></td>

<td>ZnAl</td><td></td><td>an alloy or mixture containing zinc and aluminum</td>

<td>ZnAlOx</td><td></td><td>a mixed oxide containing zinc and aluminum</td>

<td>FoundAlOy</td><td></td><td>partially oxidized mixture containing zinc and aluminum</td>

<td>ZnO</td><td>zinc oxide</td><td></td>

<td>ZnTi</td><td></td><td>an alloy or mixture containing zinc and titanium</td>

<td>ZnTiOx</td><td></td><td>mixed oxide containing zinc and titanium</td>

<td>ZnTiOy</td><td></td><td>partially oxidized mixture containing zinc and titanium</td>

<td>Zr</td><td>zirconium</td><td></td>

Patent claims