BE1010321A5 - Glass solar protection and method for manufacturing a glass tel. - Google Patents

Abstract

The present invention relates to solar protection glazing and its manufacturing process. The glazing comprises a substrate made of vitreous material carrying a coating of tin oxide / antimony formed by pyrolysis in the vapor phase. The coating contains tin and antimony in an Sb / Sn molar ratio of between 0.01 and 0.5. The substrate carrying the coating has a solar factor of less than 70%. Such glazing is used for buildings or vehicles.

Description

       

    <Desc / Clms Page number 1>
 



  Sun protection glazing and method of manufacturing such glazing
The present invention relates to solar protection glazing and a method of manufacturing such glazing.



   Transparent reflective glazing with sun protection properties is available to architects who intend it for the exterior facade of buildings. These windows reflecting the immediate environment have aesthetic qualities and, being available in several colors, constitute a source of aesthetic design. These glazings also have technical advantages since they protect the occupants of a building against solar radiation by reflection and / or absorption and eliminate the effects of glare by intense sunlight, forming a screen against glare, improving comfort. visual and reducing eye strain.



   From the technical point of view, it is desired that under sunshine conditions the glazing does not allow too much of the total incident solar radiation to pass in order to prevent the interior of a building from being overheated. The transmission of total incident solar radiation can be expressed in terms of "solar factor". As used here, the term "solar factor" corresponds to the sum of the total energy transmitted directly and the energy which is absorbed and re-radiated on the face opposite to the energy source, compared to the radiation. total energy reaching the coated glass.



   Another important application of transparent reflective glazing for solar protection is in the field of glazing for vehicles, especially for motor vehicles and railway cars, where their purpose is to protect the occupants of the vehicle against solar radiation. In this case the main energy factor to consider is the total energy transmitted directly (TE), since the energy which is absorbed inside and re-radiated (AE) is dissipated by the movement of the vehicle.



  The main objective of vehicle glazing is therefore to have a low TE factor.



   The properties of the coated substrate described below are based on standard definitions from the International Commission on Lighting ("CIE").



   The standard illuminants listed below are Illuminant C and Illuminant A. Illuminant C represents average daylight with a temperature

  <Desc / Clms Page number 2>

 with a color of 6700 K. Illuminant A represents the radiation of a Planck radiator at a temperature of around 2856 K.



   The "light transmission factor" (TL) is the percentage of the incident light flux transmitted through a substrate.



   The "light reflection factor" (RL) is the percentage of the incident light flux reflected by a substrate.



   The "selectivity" of a coated substrate intended for building glazing is the ratio of the light transmission factor to the solar factor (TL / FS),
The "purity" (p) of the substrate color refers to the excitation purity measured using Illuminant C. It is defined according to a linear scale in which a defined source of white light has a purity of 0 and the pure color has a purity of 100%. The purity of a coated substrate is measured on the side opposite the coated face.



   The term "refractive index" (n) is defined in the International Vocabulary of Lighting (CIE), 1987, page 138.



   The "dominant wavelength" (Â. O) is the peak wavelength in the range transmitted or reflected by the coated substrate.



   The "emissivity" (E) is the ratio of the energy emitted by a given surface at a given temperature to that of a perfect radiator (black body having an emissivity of 1.0) at the same temperature.



   Several techniques are known for forming coatings on a glassy substrate, including pyrolysis. Pyrolysis generally has the advantage of providing a hard coating which does not require a protective layer.



  Coatings formed by pyrolysis have long-lasting abrasion and corrosion resistance properties. This is believed to be due in particular to the fact that the process includes depositing the precursor on a substrate which is hot. Pyrolysis is also generally less expensive than other coating methods such as vacuum spraying, particularly in terms of equipment investment. The deposition of coating by other methods, for example by spraying under vacuum, leads to products having very different properties, particularly less abrasion resistance and sometimes a different refractive index.



   A wide variety of coating materials has been proposed for glazing, to meet different desired properties. Tin oxide, Sono2, is widely used, often in combination with other materials such as other metal oxides.



   British Patent 1,455,148 teaches a process for the formation by pyrolysis of a coating of one or more oxide (s) on a substrate, by spraying with

  <Desc / Clms Page number 3>

 composed of a metal or silicon, so as to modify the light transmission and / or the light reflection of the substrate, or to confer anti-static or electrical conductivity properties. Examples of the specified oxides include ZrO2, Snob, Sb203, TiO2, C0304, Cr2O3, SiO2 and mixtures thereof. Tin oxide (Sn02) is considered advantageous because of its hardness and the ease with which it provides anti-static and electrical conductivity properties.

   British Patent 2,078,213 relates to a sequential spraying process for pyrolytically forming a coating on a support made of vitreous material and mainly relates to tin oxide or indium oxide as main constituents of the coating . When its metal precursor is tin chloride, the latter is advantageously doped with a precursor chosen from ammonium bifluoride and antimony chloride in order to increase the electrical conductivity of the coating.



   It is also known that when a coating of tin oxide is formed by pyrolysis of SnCI, the presence of a dopant such as antimony chloride SbCIs, mixed directly with tin chloride SnC14, improves the absorption and reflection of part of the near infrared solar radiation.



   One of the objects of the present invention is to provide, using pyrolysis, a glazing unit having sun protection properties.



   It has been discovered that this and other advantages can be obtained by using the chemical vapor deposition (CVD) technique to apply a pyrolytic coating comprising tin and antimony oxides in a specific ratio given.



   Therefore, according to its first aspect, the present invention relates to a glazing unit according to claim 1.



   The substrate is preferably in the form of a ribbon or a sheet of glassy material, such as glass or another rigid transparent material. Given the proportion of incident solar radiation that is absorbed by the glazing, particularly in environments where it is exposed to intense or long-lasting solar radiation, there is a heating of the glazing which may require that the substrate be subjected to a treatment reinforcement. However, the durability of the coating allows the glazing to be mounted with its coated side facing outwards, which reduces the heating effect.



   Preferably the substrate is made of clear glass, although the invention extends to the use of colored glass as a substrate.

  <Desc / Clms Page number 4>

 



   The Sb / Sn molar ratio in the coating layer is preferably at least 0.03, preferably at least 0.05. This helps to ensure a high level of absorption. On the other hand, said molar ratio is preferably less than 0.21 in order to obtain a high level of the light transmission factor (TL). Preferably the ratio is less than 0.15, since beyond this level the coating layer has too high an absorption level as well as poor selectivity.



   Coated substrates according to the invention offer the advantage of a light reflection factor (RL) of less than 11%. This low level of reflection is preferred by architects for building glazing. 11 prevents the glazing from causing glare in the vicinity of the building.



     It may be useful to avoid interaction between the glass of the substrate and the coating layer of tin oxide / antimony. By way of example, it has been observed that during the pyrolytic deposition of a coating of tin oxide from tin chloride on a soda-lime glass substrate, sodium chloride resulting from the reaction of the glass with the coating precursor or with the reaction products may become incorporated into the coating, and this leads to the appearance of haze in the coating.



   An intermediate coating layer intended to reduce haze can advantageously be placed between the substrate and the tin oxide / antimony coating layer. The layer reducing the haze can be formed by pyrolysis, in an incompletely oxidized state, by bringing the substrate into contact, in a coating enclosure, with an undercoat precursor in the presence of oxygen in an amount insufficient to completely oxidize the material. of the substrate sublayer.



    The expression "incompletely oxidized material" is used here to describe a true sub-oxide, that is to say an oxide of a multivalent element in a lower valence state (for example V02 or TiO) and also to describe an oxidized material containing in its structure oxygen vacancies: an example of this latter material is SiOx or x is less than 2, which can have the general structure of Si02 but has a proportion of vacancies which would be filled with oxygen in dioxide.



   Preferably, the layer of a coating reducing the haze comprises a silicon oxide having a geometric thickness of approximately 100 nm. The particular advantage of having a silicon oxide undercoat on soda-lime glass prevents the migration of sodium ions from the glass, by diffusion or by any other means, towards the coating layer d tin oxide / antimony, either during the formation of this upper layer or during a subsequent treatment at high temperature.

  <Desc / Clms Page number 5>

 



   As a variant, the sublayer can be an "anti-reflective" sublayer such as, for example, an oxidized aluminum / vanadium layer as described in patent application GB 2 248 243.



   The glazings according to the invention have a solar factor of less than 70%, preferably less than 60% and in certain cases less than 50%. The preference for a solar factor of less than 60% appears when the glazings according to the invention are arranged with their coated face facing outwards, that is to say towards the energy source. Generally this arrangement leads to an improved solar factor compared to the arrangement of the glazing with the coated face opposite the energy source. The need for a solar factor of less than 50% appears in buildings located in parts of the world with strong sunshine. For vehicle roofs an even lower solar factor may be desirable.



   The use of colored glass is one way of obtaining a low solar factor, and it is commonly used both in architectural glazing and in automotive glazing. When comparing the effectiveness of the coating layers, it is therefore necessary to take into account the differences between the types of glass on which the respective coatings are deposited. Thus, an example of coating according to the invention deposited on clear glass gives a solar factor of 63%, while an equivalent coating deposited on green glass gives a solar factor of 44.5%.



   It is also desirable that the glazing also transmit a reasonable proportion of visible light in order to allow natural lighting of the interior of a building or of a vehicle and to allow its occupants to see outside. It is therefore desirable to increase the selectivity of the coating, that is to say to increase the ratio of the transmission factor to the solar factor. In fact the selectivity is preferably as high as possible.



   In general, the light transmission factor (TL) of the glazing according to the invention is between 40 and 65%. However, glazing having a light transmission factor of less than 40% can be used as a roof panel, for example a sunroof of a vehicle.



   Preferably, the tin oxide / antimony coating has a thickness of between 100 and 500 nm. Thick layers of tin oxide / antimony, particularly layers with a low Sb / Sn molar ratio, can provide the glazing with the advantageous combination of a low solar factor (FS) and low emissivity. Another way of obtaining this combination is the deposition on the tin oxide / antimony layer according to the invention of a low emissivity layer of doped tin oxide, for example tin oxide doped with fluorine. This arrangement is nevertheless disadvantageous in that it requires the deposition of an additional layer, which is costly in time and in money.

  <Desc / Clms Page number 6>

 



   In principle, another way of obtaining a low solar factor combined with a low emissivity is to form a coating layer of tin oxide / antimony containing a doping agent such as fluorine. For example, patent GB 2,200,139 teaches a process for forming a pyrolytic coating of tin oxide by spraying a solution which, in addition to the tin precursor, contains compounds which will give fluorine in the coating and at least one element from antimony, arsenic, vanadium, cobalt, zinc, cadmium, tungsten, tellurium and manganese.



   It would thus be possible, for example, to form a coating from reagents containing tin, antimony and fluorine in the ratios Sb / Sn = 0.028, F / Sn = 0.04. It has been found, however, that the presence of fluorine has the distinct disadvantage of hindering the incorporation of antimony into the coating rather than effectively reducing emissivity. For example, the reagents containing antimony and tin in the Sb / Sn ratio = 0.028 gives a coating having an Sb / Sn ratio of about 0.057, while the same reagents added with a reagent containing fluorine in a proportion such that F / Sn = 0.04 gives a coating having an Sb / Sn ratio of approximately 0.038.



   The invention has the advantage of simultaneously providing a solar factor (FS) of less than 60%, an emissivity of less than 0.4 (preferably less than 0.3) and a light transmission factor (TL) of more than 60% . The coated product therefore fulfills two important functions. In winter it maintains the heat in the building, due to its low emissivity. In summer it opposes the passage of solar heat in the building and thus prevents the building from overheating, due to its low solar factor. This result is especially achieved for coatings having an Sb / Sn ratio of between 0.01 and 0.12, particularly between 0.03 and 0.07, and a thickness of between 100 and 500 nm, for example between 250 and 450 nm.



   Preferably, the tin oxide / antimony coating constitutes an exposed layer and the glazing comprises a single layer of tin oxide / antimony coating.



   However, it is possible to have one or more other coating layer (s), either by pyrolysis or by other methods, to obtain certain desired optical qualities. Note however that the tin oxide / antimony layer, when deposited by pyrolysis, has sufficient mechanical durability and chemical resistance to constitute an exposed layer.



   The glazings according to the invention can be part of a single or multiple glazing. The coated surface of the glazing may be the internal surface of an exterior glazing so that the coated surface is not exposed to climatic conditions which could in other cases reduce its service life more quickly by soiling,

  <Desc / Clms Page number 7>

 physical degradation and / or oxidation, but coatings produced by pyrolysis generally have greater mechanical strength than coatings produced by other methods and can therefore be exposed to atmospheric conditions. The glazings according to the invention can also be used in laminated vitreous structures, for example in which the coated surface constitutes the internal surface of the exterior panel.



   The present invention, according to its second aspect, relates to a glazing unit according to claim 19.



   The present invention, according to its third aspect, relates to a method for forming a glazing unit according to claim 21.



   When it is desired to manufacture flat glass coated with a pyrolytic layer, it is better to do so when the glass is freshly formed. This way of proceeding is advantageous from the economic point of view since it does not require the reheating of the glass for the implementation of the pyrolysis reactions, and also allows a good quality of the coating, since it is formed on virgin glass. . The coating precursor is therefore preferably brought into contact with an upper face of a hot glass substrate constituted by freshly formed flat glass.



   The glazings according to the invention can be manufactured in the following manner. Each pyrolytic deposition step can be carried out at a temperature of at least 400 "C, ideally between 550 C and 750 C. The coatings can be formed on a sheet of glass which moves in a tunnel oven or on a glass ribbon during its formation, while it is still hot. The coatings can be formed inside the gallery which follows the equipment for forming the glass ribbon or inside the float tank on the upper surface glass ribbon as it floats on a bath of molten tin.



   The coating layers are applied to the substrate by chemical vapor deposition (CVD). This constitutes a particularly advantageous process because it provides coatings of regular thickness and composition, such uniformity of the coating being particularly important when the product has to cover a large surface. CVD provides many advantages over pyrolysis processes using spray liquids as precursors. With spray methods it is difficult to control the spraying process and achieve good coating thickness uniformity. In addition, the pyrolysis of sprayed liquids is essentially limited to the manufacture of oxide coatings, such as 5n02 and Ti02.

   It is also difficult to manufacture multi-layer coatings.

  <Desc / Clms Page number 8>

 layers with sprayed liquids because each deposition of layers causes significant cooling of the substrate. In addition, chemical vapor deposition is more economical in terms of raw materials, which results in less waste.



   The product having a coating deposited by CVD is physically different from those having coatings obtained by spraying. A coating obtained by spraying retains in particular traces of sprayed droplets as well as traces of the path of the spray nozzle, which is not the case with CVD.



   To form each coating, the substrate is brought into contact, in a coating enclosure, with a gaseous medium comprising the reactive mixture in the gas phase. The coating chamber is supplied with reactive gas by means of one or more nozzle (s), the length of which is at least equal to the width to be coated.



   Methods and devices for forming such a coating are described, for example, in French patent No. 2,348,166 (BFG Glassgroup) or in French patent application No. 2,648,453 Al (Glaverbel). These methods and devices lead to the formation of particularly resistant coatings having advantageous optical properties.



   To form the tin oxide / antimony coatings, two successive nozzles are used. The reactive mixture comprising sources of tin and antimony feeds the first nozzle. When this mixture comprises chlorides which are liquid at room temperature, it is vaporized in a stream of anhydrous carrier gas at high temperature. The vaporization is facilitated by the atomization of these reactants in the carrier gas. To produce the oxides, the chlorides are put in the presence of steam sent to the second nozzle. The steam is superheated and is also injected into a stream of carrier gas.



   Advantageously, nitrogen is used as the substantially inert carrier gas. Nitrogen is sufficiently inert for the purposes pursued and it is inexpensive in comparison with noble gases.



   Silicon oxide Si02 or SiOx sublayers can be deposited from silane SiH4 and oxygen according to the descriptions of British patent applications GB 2 234 264 and GB 2 247 691.



   If a glass substrate with an incompletely oxidized coating is exposed to an oxidizing atmosphere for a sufficient time, it can be expected that the coating will become fully oxidized, resulting in the loss of the desired properties. Therefore, such an undercoat is surmounted by the coating layer of tin oxide / antimony while it is still in an incompletely oxidized state and the substrate is still hot, so as to maintain the undercoat. layer in

  <Desc / Clms Page number 9>

 an incompletely oxidized state.

   The period during which the glass substrate carrying the freshly deposited undercoat can be exposed to an oxidizing atmosphere such as air and before the upper layer is deposited, without deterioration of the properties of the undercoat, depends on the temperature of the glass during such exposure and the nature of the undercoat.



   Advantageously, the deposition enclosure of the sub-layer is surrounded by a reducing atmosphere. The adoption of this characteristic contributes to avoiding the entry of ambient oxygen into the sub-layer deposition chamber and thus allows better control of the oxidation conditions in the sub-layer deposition chamber.



   The oxygen necessary for the deposition reactions of the sublayer can be supplied in the form of pure oxygen, but this unnecessarily increases the costs, and it is preferred that the oxygen be introduced by supplying the deposition enclosure with the air.



   It should be noted that the Sb / Sn molar ratio which is desirable in the reactive mixture does not always correspond to the ratio which is desirable in the tin / antimony coating layer.



   Preferably the source of tin is chosen from SnCL, monobutyl trichlor tin ("MBTC") and their mixtures. The source of antimony can be chosen from antimony chlorides SbCI3, SbCtg, organo-antimony compounds and their
 EMI9.1
 mixtures. Examples of suitable raw materials are SOCt-Cfg, CI1. Sb (OCH2CH3) t3, CIzSbOCHCtCHg, CIzSbOCHzCHCHsCt andCtzSbOCHzQzCI.



  The invention will now be described in more detail with reference to the following nonlimiting examples.



   In the examples, the Sb / Sn molar ratio of the coatings is determined by an X-ray analysis technique in which the X-ray count of the respective elements is compared. This technique is not as precise as if one carried out a calibration by chemical dosage, but the similarity between antimony and tin means a similar response to X-rays. The ratio of the counts observed for the respective elements thus gives a good approximation of their molar ratio.



   Colored glass is used rather than clear glass as shown in some of the examples. The properties of the different types of colored glass are presented in Table 1 below. In all cases, the properties are measured on glass samples 4 mm thick, this being the thickness of the glass used in all the examples, except for examples 1 to 7 (for which the thicknesses are shown in table 2). The initials in the headers of this table and of the other following tables (TL, TE etc.) have the meanings described above.

  <Desc / Clms Page number 10>

 



   With regard to the calculation of the solar factor, it will be noted that for light transmission factors (TL) less than 60% the effect of a low emissivity is not negligible and must be taken into account: when the emissivity decreases, the same goes for the solar factor.



   Table 1
 EMI10.1
 
 <tb>
 <tb> Type <SEP> from <SEP> glass <SEP> Green <SEP> A <SEP> Green <SEP> B <SEP> Gray <SEP> Gray <SEP> Gray
 <tb> medium <SEP> dark
 <tb> AD <SEP> in <SEP> transmission <SEP> 505, <SEP> 4/508, <SEP> 5 <SEP> 504.9 / 508, <SEP> 4 <SEP> 470, <SEP> 11493, <SEP> 9 <SEP> 493, <SEP> 2/502, <SEP> 7 <SEP> 478, <SEP> 91502, <SEP> 7
 <tb> (nm)
 <tb> [Illuminating <SEP>: <SEP> C / A]
 <tb> Purity <SEP> (%) <SEP> 2, <SEP> 913, <SEP> 4 <SEP> 2, <SEP> 1/2, <SEP> 5 <SEP> 1, <SEP> 5/0, <SEP> 8 <SEP> 5, <SEP> 615, <SEP> 1 <SEP> 2, <SEP> 6/1, <SEP> 8
 <tb> TL <SEP> (%) <SEP> 72, <SEP> 66/71, <SEP> 12 <SEP> 78, <SEP> 44/77, <SEP> 20 <SEP> 55, <SEP> 65/55, <SEP> 56 <SEP> 36, <SEP> 80 / 35.76 <SEP> 22, <SEP> 41/22, <SEP> 30
 <tb> [Illuminating <SEP>:

    <SEP> C / A]
 <tb> TE <SEP> (%) <SEP> (CIE) <SEP> 44, <SEP> 0 <SEP> 52, <SEP> 3 <SEP> 56, <SEP> 9 <SEP> 25, <SEP> 9 <SEP> 31, <SEP> 11
 <tb> FS <SEP> (%) <SEP> face <SEP> coated <SEP> 56, <SEP> 8 <SEP> 62, <SEP> 9 <SEP> 66, <SEP> 3 <SEP> 43, <SEP> 4 <SEP> 47, <SEP> 3
 <tb> TUFS <SEP> 1.28 <SEP> 1.25 <SEP> 0.84 <SEP> 0, <SEP> 85 <SEP> 0.47
 <tb> [Illuminating <SEP>: <SEP> C]
 <tb>
 
EXAMPLE 1
Clear soda-lime float glass advancing at a speed of 7 m per minute along a float tank is coated with an undercoat in a coating enclosure arranged at a location in the float tank where the glass is at a temperature of about 700 C. The supply line conveys nitrogen, silane is introduced therein at a partial pressure of 0.25% and oxygen at a partial pressure of 0.05% (ratio 0.5).

   A coating of silicon oxide SiO 2 having a thickness of 100 nm is obtained.



   The substrate provided with its sub-layer, having a thickness of 6 mm, is then immediately coated by CVD pyrolysis by means of a coating device comprising two successive nozzles. A reagent is used comprising a mixture of SnC4 as a source of tin and SbCIs as a source of antimony.



  The Sb / Sn molar ratio of the mixture is approximately 0.2. The reaction mixture is vaporized in a gas stream of anhydrous nitrogen at about 600 ° C, which feeds the first nozzle. The vaporization is favored by the atomization of these reactants in the carrier gas. Superheated steam is supplied to the second nozzle. The steam is heated to around 600 C and is also injected into a carrier gas, which is air heated to about 600 C. The gas flow rate (carrier gas + reagent) of each nozzle is 1m3 / cm in width substrate per hour, at working temperature.



   The coating process continues until the geometric thickness of the tin oxide / antimony coating overlying the substrate coated with the undercoat is 185 nm.

  <Desc / Clms Page number 11>

 



    EXAMPLES 2 TO 7
In Examples 2 to 7, the process of Example 1 is followed, but with variations in parameters such as the reactive mixture, the presence or absence of an oxide sublayer, the Sb / Sn ratio in the coating. and in the reactive mixture and the thickness of the glassy substrate. For example, in comparison with Example 1, an undercoat is not applied in Example 2 and the tin oxide / antimony coating layer has a thickness of 210 nm.

   The reactive mixtures are as follows: Example 2 and 3: the same as in Example 1 (but with a lower concentration of reactive mixtures in the carrier gas in Example 3);
Example 4: MBTC and CI1,7Sb (OCH2CH3) 1,3;
Example 5: MBTC and CIzSbOCHzCHCHsCt;
Example 6: MBTC and CtzSbOCHzCtCHCt;
Example 7: MBTC and SbCI3.



   The variations in the operating parameters of Examples 1 to 7 and the results obtained are given in Table 2 below.



   The glazings according to Examples 3 to 7 have a pleasant blue color in transmission: the dominant wavelength in transmission in the visible spectrum is between 470 and 490 nm.



   Example 6 provides glazing having a combination of a low solar factor FS and a low emissivity.



   As a variant of example 6, the Si02 sublayer is replaced by an anti-reflective sublayer of silicon oxide SiOx, according to the method of patent GB 2 247 691. In another variant, the Si02 sublayer is replaced by an oxidized aluminum / vanadium layer according to patent GB 2 248 243. In these variants the glazing does not have a purple appearance in reflection from then the uncoated face.



   EXAMPLE 8
Colored "green A" float glass advancing at a speed of 7 m per minute along a float tank is coated with an undercoat in a coating enclosure arranged at a location along the float tank where the glass is at a temperature of about 700 ° C. The supply line carries nitrogen; silane is introduced therein at a partial pressure of 0.2% and oxygen under a partial pressure of 0.5% (ratio 0.55). A coating of silicon oxide SiOx is obtained, with x approximately equal to 1.8, having a refractive index of approximately 1.7.



  The thickness of the coating is 40 nm.



   The substrate provided with the sublayer, having a thickness of 4 mm, is then coated by CVD pyrolysis. A reagent comprising a mixture of MBTC is used as the source of tin and CI1. TSOCHzCHg) as a source of antimony. The Sb / Sn molar ratio of the mixture is approximately 0.195 (mass ratio

  <Desc / Clms Page number 12>

 0.2). The reaction mixture is vaporized in a stream of anhydrous air at around 200oC, which feeds the nozzle. The vaporization is facilitated by the atomization of these reactants in the carrier gas. Steam superheated to about 2000C is then introduced.



   The coating process is continued until the geometric thickness of the tin oxide / antimony coating overlying the substrate provided with the undercoat is approximately 120 nm.



   EXAMPLES 9 TO 14
In Examples 9 to 14, the process of Example 8 is followed, but with variations as shown in Table 3 in parameters such as the thickness of the undercoat, the Sb / Sn ratio in the coating and in the reactive mixture, the thickness of the tin oxide / antimony coating layer and the color of the glass. The results of Examples 8 to 14 are shown in Table 3.



   The glazings according to Examples 9 to 14 have a pleasant blue color in transmission, the dominant wavelength in transmission in the visible spectrum being between 470 and 490 nm (Illuminant C).



   As a variant of Example 9 in which the green glass A is replaced by medium gray glass, the resulting light transmission factor (TL) is 20%, the light reflection factor (RL) is 10% and the transmission factor energy (TE) is 15%.



   EXAMPLES 15 TO 30
The process of Example 1 is followed in Examples 15 to 30 with variations in the reactive mixture, the color and thickness of the glassy substrate, the thickness of the oxide sublayer, and the Sb / Sn in the reaction mixture and in the coating. For examples 15 to 22 the reactive mixture is MBTC and Cl1. 7Sb (OCH2CH3) 3 without trifluoroacetic acid, while for Examples 23 to 30 the reactive mixture is MBTC and Cl1. 7Sb (OCH2CH3h. 3 with trifluoroacetic acid. The F / Sn ratio in the reactive mixture of these examples is 0.04.



   The variations in the operating modes, and the results obtained are shown in Table 4 for Examples 15 to 22 and in Table 5 for Examples 23 to 30. The silicon oxide SiOx used in Examples 15 to 30 has a value of x approximately equal to 1.8.

  <Desc / Clms Page number 13>

 



  Table 2
 EMI13.1
 
 <tb>
 <tb> Example <SEP> 1 <SEP> 2 <SEP> 3 <SEP> 4 <SEP> 5 <SEP> 6 <SEP> 7
 <tb> Thickness <SEP> of oxide <SEP> 185 <SEP> 210 <SEP> 105 <SEP> 120 <SEP> 105 <SEP> 445 <SEP> 110
 <tb> tin / antimony <SEP> (nm)
 <tb> Underlay <SEP> of oxide <SEP> SiO2 <SEP> absent <SEP> absent <SEP> SiO2 <SEP> SiO2 <SEP> SiO2 <SEP> SiO2
 <tb> Thickness <SEP> from <SEP> the <SEP> under <SEP> 100 <SEP> 0 <SEP> 0 <SEP> 70 <SEP> 70 <SEP> 70 <SEP> 70
 <tb> layer <SEP> (nm)
 <tb> Report <SEP> Sb / Sn <SEP> in <SEP> on <SEP> 0.48 <SEP> 0.48 <SEP> 0.46 <SEP> 0.19 <SEP> 0.15 <SEP> 0.06 <SEP> 0.18
 <tb> coating
 <tb> Report <SEP> Sb / Sn <SEP> in <SEP> them <SEP> 0.20 <SEP> 0.20 <SEP> 0.20 <SEP> 0.20 <SEP> 0.20 <SEP> 0.10 <SEP> 0.20
 <tb> reagents
 <tb> Sailing <SEP> (%) <SEP> 0.07 <SEP> 2.09 <SEP> 4.36 <SEP> to <SEP> 7.01 <SEP> low <SEP> low <SEP> low <SEP> low
 <tb> TL <SEP> (%)

    <SEP> 45.7 <SEP> 44.3 <SEP> 65.5 <SEP> 51.0 <SEP> 61.6 <SEP> 47.5 <SEP> 55.0
 <tb> RL <SEP> (%) <SEP> (face <SEP> coated) <SEP> 9.0 <SEP> 12.0 <SEP> 18.8 <SEP> 12.0 <SEP> 11.7 <SEP> 6.6 <SEP> 13.7
 <tb> FS <SEP> (%) <SEP> (face <SEP> coated) <SEP> (CIE) <SEP> 55.3 <SEP> 56.9 <SEP> 66.0 <SEP> 58.4 <SEP> 62.2 <SEP> 47.2 <SEP> 59.6
 <tb> TL / FS <SEP> 0.83 <SEP> 0.78 <SEP> 0.99 <SEP> 0.87 <SEP> 0.99 <SEP> 1.01 <SEP> 0.92
 <tb> #D <SEP> in <SEP> transmission <SEP> (nm) <SEP> 587.5 <SEP> -560 <SEP> 480.1 <SEP> 478.8 <SEP> 481.0 <SEP> 483.0 <SEP> 479.3
 <tb> Purity <SEP> from <SEP> color <SEP> in <SEP> 3.4 <SEP> 3.9 <SEP> 4.9 <SEP> 11.5 <SEP> 8.7 <SEP> 8.0 <SEP> 10.3
 <tb> transmission <SEP> (%)
 <tb> #D <SEP> in <SEP> reflection <SEP> (face <SEP> 472.3 <SEP> 494.5 <SEP> 575.3 <SEP> 579.5 <SEP> 577.6 <SEP> 490.0 <SEP> 577.0
 <tb> coated) <SEP> (nm)

  
 <tb> Purity <SEP> from <SEP> color <SEP> (%) <SEP> in <SEP> 36.9 <SEP> 7.0 <SEP> 19.1 <SEP> 35.0 <SEP> 35.2 <SEP> 6.0 <SEP> 33.1
 <tb> reflection <SEP> (face <SEP> coated)
 <tb> Emissivity <SEP>> 0.7 <SEP>> 0.7 <SEP>> 0.7 <SEP> 0.84 <SEP> 0.71 <SEP> 0.25 <SEP> 0.79
 <tb> Thickness <SEP> from <SEP> glass <SEP> (mm) <SEP> 6 <SEP> 6 <SEP> 6 <SEP> 5 <SEP> 5 <SEP> 5 <SEP> 5
 <tb>
 

  <Desc / Clms Page number 14>

 Table 3
 EMI14.1
 
 <tb>
 <tb> Example <SEP> 8 <SEP> 9 <SEP> 10 <SEP> 11 <SEP> 12 <SEP> 13 <SEP> 14
 <tb> Thickness <SEP> of oxide <SEP> 120 <SEP> 120 <SEP> 320 <SEP> 470 <SEP> 470 <SEP> 320 <SEP> 470
 <tb> tin / antimony <SEP> (nm)
 <tb> Underlay <SEP> of oxide <SEP> SiO2 <SEP> SiO2 <SEP> SiO2 <SEP> SiO2 <SEP> SiO2 <SEP> SiO2 <SEP> SiO2
 <tb> Thickness <SEP> from <SEP> the <SEP> under <SEP> 40 <SEP> 70 <SEP> 40 <SEP> 40 <SEP> 40 <SEP> 40 <SEP> 40
 <tb> layer <SEP> (nm)

  
 <tb> Report <SEP> Sb / Sn <SEP> in <SEP> on <SEP> 0.10 <SEP> 0.18 <SEP> 0.09 <SEP> 0.09 <SEP> 0.09 <SEP> 0.09 <SEP> 0.09
 <tb> coating
 <tb> Report <SEP> Sb / Sn <SEP> in <SEP> them <SEP> 0.07 <SEP> 0.20 <SEP> 0.07 <SEP> 0.07 <SEP> 0.07 <SEP> 0.07 <SEP> 0.07
 <tb> reagents
 <tb> Sailing <SEP> (%) <SEP> 0.36 <SEP> 0.1 <SEP> 1.0 <SEP> 1.8 <SEP> 1.8 <SEP> 1.0 <SEP> 1.8
 <tb> TL <SEP> (%) <SEP> [illuminant <SEP> A / <SEP> 53/55 <SEP> 39/20 <SEP> 31/32 <SEP> 31/32 <SEP> 9/9 <SEP> 40/41 <SEP> 36 [A]
 <tb> Illuminating <SEP> C]
 <tb> RL <SEP> (%) <SEP> (face <SEP> coated) <SEP> 9/10 <SEP> 11/11 <SEP> 7/7 <SEP> 7/7 <SEP> 7/7 <SEP> 8/7 <SEP> 7 [A]
 <tb> [Illuminating <SEP> A / C]
 <tb> RL <SEP> (%) <SEP> (face <SEP> no <SEP> coated <SEP> 8 <SEP> 8 <SEP> 6 <SEP> 6 <SEP> 6 <SEP> 7 <SEP> -
 <tb> [Illuminating <SEP> C]
 <tb> TE <SEP> (%) <SEP> (CIE)

    <SEP> 31 <SEP> 25 <SEP> 25 <SEP> 18 <SEP> 9 <SEP> 21 <SEP> 27
 <tb> FS <SEP> (%) <SEP> (face <SEP> coated) <SEP> (CIE) <SEP> 45 <SEP> 41 <SEP> 41 <SEP> 36 <SEP> 29 <SEP> 39 <SEP> 43
 <tb> TL / FS <SEP> 1.2 / 1.2 <SEP> 0.95 / 0.98 <SEP> 0.76 / 0.78 <SEP> 0.86 / 0.89 <SEP> 0.31 / 0.31 <SEP> 1.02 / 1.05 <SEP> 5.4 [A]
 <tb> #D <SEP> in <SEP> transmission <SEP> (nm) <SEP> 505.4 / 498.6 <SEP> 497.2 / 487.0 <SEP> 494.8 / 481.9 <SEP> 497.2 / 487.2 <SEP> 494.2 / 480.0 <SEP> 501.0 / 491.6 <SEP> 493.4 <SEP> [A]
 <tb> Purity <SEP> from <SEP> color <SEP> in <SEP> 4.4 / 4.2 <SEP> 6.2 / 8.9 <SEP> 4.9 / 8.1 <SEP> 7.6 / 10.8 <SEP> 7.0 / 11.8 <SEP> 7.2 / 8.6 <SEP> 5.4 [A]
 <tb> transmission <SEP> (%)
 <tb> #D <SEP> in <SEP> reflection <SEP> (face <SEP> 487.9 / 478.1 <SEP> -572.5 / 566.9 <SEP> -511.8 / 512.2 <SEP> -576.9 / 559.8 <SEP> -55.4 / 550.1 <SEP> -512.5 / 513.6 <SEP> -576.0 [A]
 <tb> coated) <SEP> (nm)

  
 <tb> Purity <SEP> from <SEP> color <SEP> (%) <SEP> in <SEP> 7.4 / 14.6 <SEP> 2.2 / 2.9 <SEP> 17.2 / 16.3 <SEP> 6.0 / 1.2 <SEP> 2.1 / 6.6 <SEP> 15.4 / 14.5 <SEP> 1.5 [A]
 <tb> reflection <SEP> (face <SEP> coated)
 <tb> Emissivity <SEP> 0.71 <SEP> 0.85 <SEP> 0.44 <SEP> 0.35 <SEP> 0.35 <SEP> 0.44 <SEP> 0.35
 <tb> Thickness <SEP> from <SEP> glass <SEP> (mm) <SEP> Green <SEP> A <SEP> Green <SEP> A <SEP> Gray <SEP> Green <SEP> B <SEP> Gray <SEP> dark <SEP> Green <SEP> A <SEP> Clear
 <tb>
 

  <Desc / Clms Page number 15>

 Table 4
 EMI15.1
 
 <tb>
 <tb> Example <SEP> 15 <SEP> 16 <SEP> 17 <SEP> 18 <SEP> 19 <SEP> 20 <SEP> 21 <SEP> 22
 <tb> Thickness <SEP> of oxide <SEP> 320 <SEP> 320 <SEP> 320 <SEP> 390 <SEP> 390 <SEP> 390 <SEP> 390
 <tb> tin / antimony <SEP> (nm)

  
 <tb> Underlay <SEP> of oxide <SEP> SiOx <SEP> SiOx <SEP> SiOx <SEP> SiOx <SEP> SiOx <SEP> SiOx <SEP> SiOx
 <tb> Thickness <SEP> from <SEP> the <SEP> under <SEP> 60 <SEP> 60 <SEP> 60 <SEP> 60 <SEP> 80 <SEP> 80 <SEP> 80 <SEP> 80
 <tb> layer <SEP> (nm) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately)
 <tb> Report <SEP> Sb / Sn <SEP> in <SEP> on <SEP> 0.053 <SEP> 0.053 <SEP> 0.053 <SEP> 0.053 <SEP> 0.058 <SEP> 0.058 <SEP> 0.058 <SEP> 0.058
 <tb> coating
 <tb> Report <SEP> Sb / Sn <SEP> in <SEP> them <SEP> 0.028 <SEP> 0.028 <SEP> 0.028 <SEP> 0.028 <SEP> 0.028 <SEP> 0.028 <SEP> 0.028 <SEP> 0.028
 <tb> reagents
 <tb> Sailing <SEP> (%) <SEP> 0.65 <SEP> 0.65 <SEP> 0.65 <SEP> 0.65 <SEP> 1,2 <SEP> 1,2 <SEP> 1,2 <SEP> 1,2
 <tb> TL <SEP> (%) <SEP> [illuminant <SEP> C] <SEP> 68.8 <SEP> 55.7 <SEP> 60.1 <SEP> 28.2 <SEP> 61,

  0 <SEP> 49.2 <SEP> 25.0 <SEP> 53.1
 <tb> RL <SEP> (%) <SEP> (face <SEP> coated) <SEP> 8.9 <SEP> 8.2 <SEP> 8.4 <SEP> 7.2 <SEP> 9.0 <SEP> 8.0 <SEP> 7.2 <SEP> 6.9
 <tb> RL <SEP> (%) <SEP> (face <SEP> no <SEP> coated <SEP> 8.9 <SEP> 7.3 <SEP> 7.8 <SEP> 5.0 <SEP> 7.8 <SEP> 6.5 <SEP> 4.8 <SEP> 8.2
 <tb> TE <SEP> (%) <SEP> (CIE) <SEP> 50.8 <SEP> 28.3 <SEP> 33.1 <SEP> 15.8 <SEP> 43.0 <SEP> 24.5 <SEP> 13.7 <SEP> 28.5
 <tb> FS <SEP> (%) <SEP> (face <SEP> coated) <SEP> (CIE) <SEP> 60.3 <SEP> 43.6 <SEP> 47.2 <SEP> 34.4 <SEP> 54.7 <SEP> 40.9 <SEP> 32.9 <SEP> 40.1
 <tb> TL / TE <SEP> 1.35 <SEP> 2.00 <SEP> 1.82 <SEP> 1.75 <SEP> 1.42 <SEP> 1.96 <SEP> 1.79 <SEP> 1.86
 <tb> TL / FS <SEP> 1.15 <SEP> 1.27 <SEP> 1.28 <SEP> 0.82 <SEP> 1.11 <SEP> 1.20 <SEP> 0.76 <SEP> 1.20
 <tb> #D <SEP> in <SEP> transmission <SEP> (nm) <SEP> 524.0 <SEP> 506.2 <SEP> 506.0 <SEP> 494.0 <SEP> 496.0 <SEP> 500.7 <SEP> 593,

  4 <SEP> 499.5
 <tb> Purity <SEP> from <SEP> color <SEP> in <SEP> 0.5 <SEP> 3.1 <SEP> 2.3 <SEP> 5.8 <SEP> 2.2 <SEP> 4.7 <SEP> 7.5 <SEP> 4.1
 <tb> transmission <SEP> (%)
 <tb> #D <SEP> in <SEP> reflection <SEP> (face <SEP> 482.9 <SEP> 484.2 <SEP> 484.0 <SEP> 482.9 <SEP> -495.2 <SEP> -493.8 <SEP> -495.0 <SEP> -550.3
 <tb> coated) <SEP> (nm)
 <tb> Purity <SEP> from <SEP> color <SEP> (%) <SEP> in <SEP> 14.5 <SEP> 16.2 <SEP> 15.8 <SEP> 18.0 <SEP> 5.0 <SEP> 4.4 <SEP> 6.4 <SEP> 7.0
 <tb> reflection <SEP> (face <SEP> coated)
 <tb> Emissivity <SEP> 0.29 <SEP> 0.29 <SEP> 0.29 <SEP> 0.29 <SEP> 0.27 <SEP> 0.27 <SEP> 0.27 <SEP> 0.27
 <tb> Thickness <SEP> from <SEP> glass <SEP> (mm)

    <SEP> Clear <SEP> Green <SEP> A <SEP> Green <SEP> B <SEP> Gray <SEP> medium <SEP> Clear <SEP> Green <SEP> A <SEP> Gray <SEP> medium <SEP> Green <SEP> B
 <tb>
 

  <Desc / Clms Page number 16>

 Table 5
 EMI16.1
 
 <tb>
 <tb> Example <SEP> 23 <SEP> 24 <SEP> 25 <SEP> 26 <SEP> 27 <SEP> 28 <SEP> 29 <SEP> 30
 <tb> Thickness <SEP> of oxide <SEP> 290 <SEP> 290 <SEP> 290 <SEP> 290 <SEP> 410 <SEP> 410 <SEP> 410 <SEP> 410
 <tb> tin / antimony <SEP> (nm)
 <tb> Underlay <SEP> of oxideSiOx <SEP> SiOx <SEP> SiOx <SEP> SiOx <SEP> SiOx <SEP> SiOx <SEP> SiOx <SEP> SiOx
 <tb> Thickness <SEP> from <SEP> the <SEP> sub- <SEP> 80 <SEP> 80 <SEP> 80 <SEP> 80 <SEP> 90 <SEP> 90 <SEP> 90 <SEP> 90
 <tb> layer <SEP> (nm) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately) <SEP> (approximately)
 <tb> Report <SEP> Sb / Sn <SEP> in <SEP> on <SEP> 0.038 <SEP> 0,

  038 <SEP> 0.038 <SEP> 0.038 <SEP> 0.037 <SEP> 0.037 <SEP> 0.037 <SEP> 0.037
 <tb> coating
 <tb> Report <SEP> Sb / Sn <SEP> in <SEP> them <SEP> 0.028 <SEP> 0.028 <SEP> 0.028 <SEP> 0.028 <SEP> 0.028 <SEP> 0.028 <SEP> 0.028 <SEP> 0.028
 <tb> reactivs
 <tb> Sailing <SEP> (%) <SEP> 0.82 <SEP> 0.82 <SEP> 0.82 <SEP> 0.82 <SEP> 1,2 <SEP> 1,2 <SEP> 1,2 <SEP> 1,2
 <tb> TL <SEP> (%) <SEP> [Illuminating <SEP> C] <SEP> 70, <SEP> 2 <SEP> 56, <SEP> 7 <SEP> 61.0 <SEP> 28.7 <SEP> 64, <SEP> 2 <SEP> 51, <SEP> 9 <SEP> 26.9 <SEP> 56, <SEP> 4
 <tb> RL <SEP> (%) <SEP> (face <SEP> coated) <SEP> 10, <SEP> 0 <SEP> 9.0 <SEP> 9.2 <SEP> 8.0 <SEP> 8.8 <SEP> 8.1 <SEP> 7.2 <SEP> 8, <SEP> 3
 <tb> RL <SEP> (%) <SEP> (face <SEP> no <SEP> coated) <SEP> 9.5 <SEP> 8.0 <SEP> 8.3 <SEP> 5.

    <SEP> 2 <SEP> 7.7 <SEP> 6.6 <SEP> 4.8 <SEP> 6.9
 <tb> TE <SEP> (%) <SEP> (CIE) <SEP> 54.3 <SEP> 29.5 <SEP> 34.7 <SEP> 16.6 <SEP> 47.2 <SEP> 26.1 <SEP> 14.6 <SEP> 30.6
 <tb> FS <SEP> (%) <SEP> (face <SEP> coated) <SEP> (CIE) <SEP> 63, <SEP> 0 <SEP> 44.5 <SEP> 48.3 <SEP> 34.9 <SEP> 57.7 <SEP> 42.0 <SEP> 33, <SEP> 6 <SEP> 45, <SEP> 4
 <tb> Turne <SEP> 1.30 <SEP> 1, <SEP> 90 <SEP> 1.74 <SEP> 1.71 <SEP> 1.36 <SEP> 2.00 <SEP> 1.73 <SEP> 1, <SEP> 81
 <tb> TUFS <SEP> 1.11 <SEP> 1.27 <SEP> 1.27 <SEP> 0.83 <SEP> 1, <SEP> 10 <SEP> 1.24 <SEP> 0.76 <SEP> 1, <SEP> 24
 <tb> To.

    <SEP> o <SEP> in <SEP> transmission <SEP> (nm) <SEP> 581.3 <SEP> 538.8 <SEP> 549.4 <SEP> 498.5 <SEP> 568.6 <SEP> 535.9 <SEP> 502.7 <SEP> 543.7
 <tb> Purity <SEP> from <SEP> color <SEP> in <SEP> 2.9 <SEP> 2.9 <SEP> 2.7 <SEP> 3.3 <SEP> 3.5 <SEP> 3.7 <SEP> 3.6 <SEP> 3.5
 <tb> transmission <SEP> (%)
 <tb> #D <SEP> in <SEP> reflection <SEP> fe (face <SEP> 510.3 <SEP> 508.6 <SEP> 508.9 <SEP> 507.2 <SEP> 549.3 <SEP> 505.1 <SEP> 491.8 <SEP> 507.0
 <tb> coated) <SEP> (nm)
 <tb> Purity <SEP> from <SEP> color <SEP> (%) <SEP> in <SEP> 8.1 <SEP> 10.1 <SEP> 9.6 <SEP> 11.3 <SEP> 3.3 <SEP> 1.1 <SEP> 1,2 <SEP> 1.0
 <tb> reflection <SEP> (face <SEP> coated)
 <tb> Emissivity <SEP> 0.28 <SEP> 0.28 <SEP> 0.28 <SEP> 0.28 <SEP> 0.23 <SEP> 0.23 <SEP> 0.23 <SEP> 0,

  23
 <tb> Color <SEP> from <SEP> glass <SEP> Clear <SEP> Green <SEP> A <SEP> Green <SEP> B <SEP> Gray <SEP> medium <SEP> Clear <SEP> Green <SEP> A <SEP> Gray <SEP> medium <SEP> Green <SEP> B
 <tb>



    

Claims (23)

CLAIMS 1. Glazing comprising a substrate of vitreous material carrying a coating which comprises a single layer of tin oxide / antimony characterized in that the coating is formed by pyrolysis in the vapor phase and contains tin and antimony in a Sb / Sn molar ratio of between 0.01 and 0.5 and in that the substrate carrying the coating has a solar factor (FS) of less than 70%.  2. Glazing according to claim 1, characterized in that the molar ratio Sb / Sn is at least 0.03.  3. Glazing according to claim 2, characterized in that the Sb / Sn molar ratio is at least 0.05.  4. Glazing according to one of claims 1 to 3, characterized in that the Sb / Sn molar ratio is less than 0.21.  5. Glazing according to one of claims 1 or 4, characterized in that the Sb / Sn molar ratio is between 0.01 and 0.12.  6. Glazing according to claim 5, characterized in that the Sb / Sn molar ratio is between 0.03 and 0.07.  7. Glazing according to one of claims 1 to 6, characterized in that an intermediate layer reducing the haze is disposed between the substrate and the coating of tin oxide / antimony.  8. Glazing according to claim 7, characterized in that said intermediate layer reducing the haze comprises silicon oxide.  9. Glazing according to one of claims 1 to 8, characterized in that the solar factor is less than 60%.    10. Glazing according to claim 9, characterized in that the solar factor is less than 50%.  11. Glazing according to one of claims 1 to 10, characterized in that the light transmission factor (TL) is between 40 and 65%.  12. Glazing according to one of claims 1 to 11, characterized in that said coating of tin oxide / antimony has a thickness between 100 and 500 nm.  13. Glazing according to claim 12, characterized in that said coating of tin oxide / antimony has a thickness between 250 and 450 nm.  14. Glazing according to one of claims 1 to 13, characterized in that the coating of tin oxide / antimony constitutes an exposed layer.  <Desc / Clms Page number 18>    15. Glazing according to one of claims 1 to 14, characterized in that the tin oxide / antimony layer modifies the solar factor of the coated glazing relative to the vitreous substrate so that the substrate carrying the coating has a solar factor (FS) less than 70%.  16. Glazing according to one of claims 1 to 15, characterized in that the tin oxide / antimony coating is devoid of fluorine.  17. Glazing according to one of claims 1 to 16, characterized in that the glazing is a solar protection glazing for a vehicle.  18. Glazing according to one of claims 1 to 16, characterized in that the glazing is a solar protection glazing for building.  19. The use of a coating which comprises a single layer of tin oxide / antimony formed by vapor phase pyrolysis on a glassy substrate or the coating contains tin and antimony in a ratio molar Sb / Sn between 0.01 and 0.5 to give the glazing a solar factor (FS) of less than 70%.  20. The use of a coating according to claim 19, characterized in that the coated glazing conforms to one of claims 1 to 18.  21. A method of forming a glazing unit comprising the deposition by pyrolysis, on a substrate of vitreous material, of a coating of tin oxide / antimony, characterized in that the deposition is carried out from a reactive mixture in vapor phase comprising a tin source and an antimony source, the tin / antimony molar ratio in the mixture being between 0.01 and 0.5 so that the coated substrate has a solar factor (FS) of less than 70 %.  22. Method according to claim 21, characterized in that said source of tin is chosen from SnCl4, monobutyl trichlor tin and their mixtures.  23. Method according to one of claims 21 or 22, characterized in that the source of antimony is chosen from antimony chlorides, organo-antimony compounds and their mixtures.