Coating with solar control properties for a glass substrate

Abstract

The invention relates to a glass substrate including a stack of coating layers having control properties, in which stack comprises at least one niobium metal layer located between a layer of a dielectric material selected from Si.sub.3N.sub.4 or TiOx and a layer of a protective metal material selected from TIN or NiCr, conferring solar control and heat resistance properties on the glass substrate.

Claims

1. A glass substrate comprising a first layer comprising a dielectric material over the glass substrate; a metal layer over the first layer; a protective layer over the metal layer comprising a metal alloy; a layer of metallic material over the protective layer; and a second layer comprising a second dielectric material; wherein the glass substrate coated with the first layer, the metal layer, the protective layer, the layer of metallic material, and the second layer has a visible light transmission from 5% to 60%, a solar transmission from 5% to 40% and a solar factor of less than 0.5.

2. The substrate as claimed in claim 1, wherein the metal layer has a thickness between 2 and 40 nm.

3. The substrate as claimed in claim 1, wherein the dielectric material or the second dielectric material comprises Si.sub.3N.sub.4 and the first layer or the second layer has a thickness between 10 and 50 nm.

4. The substrate as claimed in claim 1, wherein the protective layer has a thickness between 1 and 20 nm.

5. The substrate as claimed in claim 1, wherein the layer of metallic material comprises TiN and has a thickness between 5 and 20 nm.

6. The substrate as claimed in claim 1, wherein the metal alloy comprises NiCr and has a thickness between 1 and 10 nm.

7. The substrate as claimed in claim 1, wherein the dielectric material in the first layer comprises Si.sub.3N.sub.4; wherein the metal layer comprises Nb; wherein the metal alloy in the protective layer comprises NiCr; wherein the layer of metallic material comprises TiN; and wherein the second dielectric material in the second layer comprises Si.sub.3N.sub.4.

8. The substrate as claimed in claim 1 wherein the substrate comprises a glass side opposite the first layer, wherein the glass side of the substrate has a E value no greater than 5.

9. The substrate as claimed in claim 1, wherein the first layer has a thickness of 10 to 50 nm; wherein the metal layer has a thickness of 2 to 40 nm; wherein the protective layer has a thickness of 1 to 10 nm; wherein the layer of metallic material has a thickness of 5 to 20 nm; and wherein the second layer has a thickness of 10 to 50 nm.

10. The substrate as claimed in claim 1, wherein the dielectric material in the first layer comprises SiAlN; wherein the metal layer comprises Nb; wherein the metal alloy in the protective layer comprises NiCr; wherein the layer of metallic material comprises TiN; and wherein the second dielectric material in the second layer comprises SiAlN.

11. A glass substrate comprising a first layer comprising a dielectric material over the glass substrate; a metal layer over the first layer; a protective layer over the metal layer comprising a metal alloy; a layer of metallic material over the protective layer; and a second layer comprising a second dielectric material; wherein the first layer has a thickness of 10 to 50 nm; wherein the metal layer has a thickness of 2 to 40 nm; wherein the protective layer has a thickness of 1 to 10 nm; wherein the layer of metallic material has a thickness of 5 to 20 nm; and wherein the second layer has a thickness of 10 to 50 nm.

12. The glass substrate as claimed in claim 11, wherein the dielectric material in the first layer comprises Si.sub.3N.sub.4 or SiAlN; wherein the metal layer comprises Nb; wherein the metal alloy in the protective layer comprises NiCr; wherein the layer of metallic material comprises TiN; and wherein the second dielectric material in the second layer comprises Si.sub.3N.sub.4 or SiAlN.

13. The substrate as claimed in claim 11 wherein the substrate comprises a glass side opposite the first layer, and wherein the glass side has a E value no greater than 5.

14. A glass substrate comprising a first layer comprising a dielectric material over the glass substrate; a metal layer over the first layer comprising Nb; a protective layer over the metal layer comprising an alloy of nickel and chromium; a layer of metallic material over the protective layer comprising TiN; and a second layer comprising a second dielectric material.

15. The glass substrate of claim 14, wherein the dielectric material and the second dielectric material comprise Si.sub.3N.sub.4.

16. The glass substrate of claim 14, wherein the dielectric material and the second dielectric material comprise SiAlN.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows the schematic diagram of a coating with solar control properties for a substrate, in accordance with a first embodiment of the present invention; and,

(2) FIG. 2 shows the schematic diagram of a coating with solar control properties to a substrate, in accordance with a second embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

(3) The present invention describes coatings with solar control properties deposited on glass intended for architectural, automotive, monolithic or laminated use. Solar control refers to the ability to modify the amount of transmitted, reflected and absorbed solar radiation. Glass having characteristics of mechanical strength and heat treatment strength, light transmittance from 5 to 60%, solar transmission from 5 to 40% and a solar factor less than 0.5.

(4) In the example illustrated in FIG. 1, the CS solar control coating consists of five (5) layers: A substrate (1), on which a first layer (2) of a dielectric material such as Si.sub.3N.sub.4 with a thickness of 10 to 50 nm is deposited. This first layer also serves as a support for a metal layer (3), reflective to infrared, such as Nb, which is the metal layer conferring solar properties and thermal resistance to the configuration, since it is an element resistant to oxidation during tempering. The Nb thickness is approximately 2 to 40 nm. Subsequently, an alloy of protective material (4) preferably a NiCr alloy, with a thickness of about 1 to 10 nm, is deposited on it for protecting the metal layer from oxidation. The NiCr alloy protects the Nb layer during a sputtering process preventing its nitriding and modification of the optical properties of the material. Then a layer of metallic material (5), such as titanium nitride (TiN) is applied, with a thickness of about 5 to 20 nm, to improve the surface properties of the substrate, reinforcing the mechanical and chemical protection of the coating on the substrate; and finally, a dielectric material (6) such as Si.sub.3N.sub.4 (Silicon Nitride), with a thickness of about 10 to 50 nm, in order to increase solar control properties, particularly to adjust the transmittance in the visible range.

(5) In the example illustrated in FIG. 2, a solar control coating CS, also formed of five layers, is shown schematically. In FIG. 2 a glass substrate (7) is shown, on which a first layer (8), corresponding to a dielectric material such as Si.sub.3N.sub.4, is deposited. Layer (8) can be applied with a thickness of 10 to 50 nm. Afterward a layer of diffusion barrier (9) is deposited, i.e. TiO.sub.2, with a thickness between 1 and 20 nm. Then a metal layer (10) reflective to infrared, such as Nb, which is the metal layer conferring solar properties and thermal resistance to the configuration, because it is resistant to oxidation during tempering. The metal layer (10) can be applied with a thickness of 2 to 40 nm.

(6) The following layer is a metallic material (11) such as Titanium Nitride (TiN), to improve the surface properties of the substrate, reinforcing the mechanical and chemical protection to the coating on the substrate. Said layer (11) can be applied with a thickness of between 5 and 20 nm; and finally, a dielectric material (12) such as Si.sub.3N.sub.4, with a thickness of between 10 and 50 nm, in order to increase solar control properties, in particular to adjust the transmittance in the visible range.

(7) Based on the coatings described in FIGS. 1 and 2, tests were performed to measure the visible spectrum (380-780 nm) and generate values of vectors L*, a*, b* measured for transmission (transmitted color) and reflection (reflected color) on both surfaces; likewise, the parameters of visible light transmission or reflection (described as Y) according to the rules established by the International Commission on Illumination (C.I.E.) were determined for simulating daylight (Illuminant D65) to a 10 observer. Color differences (SE) were calculated using CIELAB (ISO 7724/3) E=[(L*).sup.2+(a*).sup.2+(b*).sup.2].sup.0.5

(8) Tables 1 to 4 show various tests according to the examples shown in FIGS. 1 and 2, which were performed with a speed of 1.0 meters/minute.

(9) The precursor commercial material of Si, usually contains up to 10% of Al which, when reacting in nitrogen plasma (80% N.sub.2+20% Ar) produces Si.sub.3N.sub.4. The presence of Al is justified to improve the conductivity of Si that suffers by itself, additionally it provides stability to target against thermal shock during its use in the process. Si.sub.3N.sub.4 is a dielectric material that when applied in contact with glass, provides chemical resistance acting as a barrier that blocks the migration of Na.sup.+ from glass during tempering and when applied to the upper layer provides mechanical strength (abrasion) and corrosion resistance (etching) and prevents migration of oxygen during tempering.

(10) The TiN is applied from a Ti reactive cathode with nitrogen plasma (80% N.sub.220% Ar) is widely used in solar control products such as Vitro AP8, which contains a stainless steel film and, on top of it, a coating of TiN; this product is used in the architectural market with characteristics of solar control, providing chemical and mechanical resistance, without being a hardenable coating. In the configuration described here, it is applied on the metal layer or NiCr alloy complementing the functional layers of solar control, additionally, this film reinforces the mechanical and chemical protection of the coating.

(11) Titanium dioxide (TiO.sub.2) is applied via a ceramic cathode in an inert atmosphere (100% Ar). It acts as a barrier providing mechanical and chemical durability reinforcing the Si.sub.3N.sub.4 and niobium layer. The advantage of this material is that it does not affect the transmission of light, i.e. visibility properties are not modified. The function of this dielectric layer when applied below the functional metallic layer is to increase the diffusion of sodium in glass during tempering. Following the approach of the tests is shown in the following tables:

(12) TABLE-US-00001 TABLE 1 Test Test 1 (Annealed sheet - Level 1 NiCr) Film Material Deposition Gas Power (kW) Film 1 SiAl 20% Ar80% N.sub.2 24.0 Film 2 Nb 100% Ar 8.5 Film 3 NiCr 100% Ar 0.8 Film 4 Ti 20% Ar80% N.sub.2 18.0 Film 5 SiAl 20% Ar80% N.sub.2 30.0

(13) TABLE-US-00002 TABLE 2 Test Test 2 (Annealed sheet - Level 2 NiCr) Film Material Deposition Gas Power (kW) Film 1 SiAl 20% Ar80% N2 24.0 Film 2 Nb 100% Ar 8.5 Film 3 NiCr 100% Ar 1.5 Film 4 Ti 20% Ar80% N2 18.0 Film 5 SiAl 20% Ar80% N2 30.0

(14) TABLE-US-00003 TABLE 3 Test Test 3 (Annealed sheet - Level 1 TiOx) Film Material Deposition Gas Power (kW) Film 1 SiAl 20% Ar80% N2 24.0 Film 2 TiOx 100% Ar 14.0 Film 3 Nb 100% Ar 8.5 Film 4 Ti 20% Ar80% N2 18.0 Film 5 SiAl 20% Ar80% N2 30.0

(15) TABLE-US-00004 TABLE 4 Test Test 4 (Annealed sheet - Level 2 TiOx) Film Material Deposition Gas Power (kW) Film 1 SiAl 20% Ar80% N2 24.0 Film 2 TiOx 100% Ar 20.0 Film 3 Nb 100% Ar 8.5 Film 4 Ti 20% Ar80% N2 18.0 Film 5 SiAl 20% Ar80% N2 30.0

(16) Once the different films were deposited on glass, each one of the sheets was characterized. Data generated from the readings on the test sheets with titanium oxide and nickel-chromium are as follows:

(17) TABLE-US-00005 Test Test 1 (Annealed sheet - Level 1 NiCr) Glass side reflected Film side reflected Vector Transmitted color color color Y 21.74 29.12 40.92 L* 53.75 60.89 70.12 a* 2.12 3.69 2.55 b* 2.39 4.46 15.44

(18) TABLE-US-00006 Test Test 2 (Annealed sheet - Level 2 NiCr) Glass side reflected Film side reflected Vector Transmitted color color color Y 20.47 30.48 41.84 L* 52.36 62.07 70.76 a* 2.14 3.68 2.71 b* 2.45 3.88 16.64

(19) TABLE-US-00007 Test Test 3 (Annealed sheet - Level 1 TiOx) Glass side reflected Film side reflected Vector Transmitted color color color Y 23.15 25.71 43.48 L* 55.23 57.76 71.88 a* 2.33 3.41 2.29 b* 3.55 2.26 14.72

(20) TABLE-US-00008 Test Test 4 (Annealed sheet - Level 2 TiOx) Glass side reflected Film side reflected Vector Transmitted color color color Y 23.93 23.58 44.91 L* 56.02 55.67 72.83 a* 2.35 3.41 1.9 b* 4.38 0.05 14.32

(21) After analyzing the results, tempering tests were performed at 700 C. for 5 minutes (6 mm light substrate) with tests 1, 2, 3 and 4 where titanium oxide and nickel-chromium were added, for subsequently characterizing them. The results are shown below:

(22) TABLE-US-00009 Test Test 1 Level 1 NiCr Glass side Glass side Film side Film side Transmitted Transmitted reflected reflected reflected reflected color color color color color color Vector (annealed) (tempered) (annealed) (tempered) (annealed) (tempered) Y 19.61 19.93 33.16 29.97 40.74 29.45 L* 51.39 51.76 64.29 61.63 69.99 61.17 a* 1.95 1.64 3.37 2.56 2.67 1.99 b* 2.6 3.96 3.16 3.03 18.38 16.28 E 1.44 1.78 9.10

(23) TABLE-US-00010 Test Test 2 Level 2 NiCr Glass side Glass side Film side Film side Transmitted Transmitted reflected reflected reflected reflected color color color color color color Vector (annealed) (tempered) (annealed) (tempered) (annealed) (tempered) Y 20.47 18.83 30.48 30.7 41.84 53.9 L* 52.36 50.49 62.07 62.26 70.76 78.41 a* 2.14 0.59 3.68 3.04 2.71 2.23 b* 2.45 3.66 3.88 2.59 16.64 17.44 E 2.74 1.52 7.83

(24) TABLE-US-00011 Test Test 3 Level 1 TiOx Glass side Glass side Film side Film side Transmitted Transmitted reflected reflected reflected reflected color color color color color color Vector (annealed) (tempered) (annealed) (tempered) (annealed) (tempered) Y 23.15 22.03 25.71 28.5 44.91 47.57 L* 55.23 54.06 57.76 60.34 72.83 74.56 a* 2.33 1.08 3.41 3.15 1.9 2.7 b* 3.55 4.23 2.26 1.29 14.32 18.7 E 1.86 2.93 5.62

(25) TABLE-US-00012 Test Test 4 Level 2 TiOx Glass side Glass side Film side Film side Transmitted Transmitted reflected reflected reflected reflected color color color color color color Vector (annealed) (tempered) (annealed) (tempered) (annealed) (tempered) Y 23.93 21.7 23.58 27.22 44.91 49.27 L* 56.02 53.71 55.67 59.18 72.83 75.62 a* 2.35 1.07 3.41 2.79 1.9 2.64 b* 4.38 4.5 0.05 0.44 14.32 18.15 E 2.52 3.55 4.83

(26) As can be noted, tests 3 and 4 show good stability in the transmitted color and reflected color values in the glass side, coupled with a significant improvement shown in stability of visible reflection values in the film side (Y). In the case of test 2 (Level 2 NiCr), the main difference observed is the reflection level change in the film side (Y) and consequently the L* vector. This change is tolerable as long as vectors a* and b* remain stable as well as the transmitted color and reflected color values in the glass side, which would lead to a change in hue tolerable to the human eye. On the other hand, in Test 3 (Level 1 TiOx) the main change is attributed to variations in the L* and b* vectors reflected by the film side surface, resulting in changes in hue of film that might be noticeable. From the above it is shown that incorporation of TiOx and NiCr materials brings significant improvements in the performance of the film during tempering giving greater protection to the functional layer of Niobium against temperature, sodium migration from the glass surface and considerable changes in film color.

(27) Tempering tests 1 to 4 were subjected to accelerated weathering tests; moisture testing at high temperature; etching tests in salt spray chamber; immersion etching tests; and abrasion tests

(28) Tests 1, 2, 3 and 4 were subjected to accelerated weathering to validate the durability of the film using a Singleton brand saline chamber according to ASTM D1117 and ISO 9017 standards, where tempered sheets of each test were exposed to a corrosive environment consisting in a fog of 20% NaCl at 35 C. for 750 hours and 95% humidity. Sheets were monitored every 24 hours to visualize the possible presence of defects in the film (lines, pinhole, degradation, etc.) and every 10 days readings were made on the product to visualize changes in film properties. The results are shown below:

(29) TABLE-US-00013 Test 1 - SiNx/Nb/NiCr/Tinx/SiNx (Level 1 NiCr) HCl 0.1N HNO.sub.3 0.1N H.sub.2SO.sub.4 0.1N Before After Change Before After Change Before After Change Transmitted Color Y 18.81 18.58 0.23 18.81 18.94 0.13 18.81 20.47 1.66 L* 50.47 50.19 0.28 50.47 50.62 0.15 50.47 52.36 1.89 a* 0.57 1.06 0.49 0.57 1.02 0.45 0.57 0.86 0.29 b* 3.50 3.82 0.32 3.50 3.73 0.23 3.50 3.35 0.15 E 0.65 0.53 1.92 Glass surface reflected color Y 30.21 31.01 0.80 30.21 30.37 0.16 30.21 30.12 0.09 L* 61.84 62.51 0.67 61.84 61.97 0.13 61.84 61.76 0.08 a* 3.06 3.07 0.01 3.06 3.10 0.04 3.06 3.07 0.01 b* 2.41 2.63 0.22 2.41 2.67 0.26 2.41 2.97 0.56 E 0.71 0.29 0.57 Film surface reflected color Y 54.08 56.80 2.72 54.08 57.41 3.33 54.08 55.07 0.99 L* 78.51 80.07 1.56 78.51 80.41 1.90 78.51 79.08 0.57 a* 1.97 2.21 0.24 1.97 2.24 0.27 1.97 1.76 0.21 b* 16.54 18.15 1.61 16.54 16.83 0.29 16.54 19.54 3.00 E 2.25 1.94 3.06 NaOH 0.1N NH.sub.4OH 0.5N Before After Change Before After Change Transmitted Color Y 18.81 17.09 1.72 18.81 17.29 1.52 L* 50.47 48.37 2.10 50.47 48.63 1.84 a* 0.57 0.89 0.32 0.57 0.43 0.14 b* 3.50 1.80 1.70 3.50 1.83 1.67 E 2.72 2.49 Glass surface reflected color Y 30.21 27.03 3.18 30.21 26.30 3.91 L* 61.84 59.00 2.84 61.84 58.32 3.52 a* 3.06 2.62 0.44 3.06 2.56 0.50 b* 2.41 1.50 0.91 2.41 1.41 1.00 E 3.01 3.69 Film surface reflected color Y 54.08 75.12 21.04 54.08 71.92 17.84 L* 78.51 89.45 10.94 78.51 87.93 9.42 a* 1.97 1.03 0.94 1.97 0.71 1.26 b* 16.54 7.78 8.76 16.54 6.70 9.84 E 14.05 13.68

(30) TABLE-US-00014 Test 2 - SiNx/Nb/NiCr/TiNx/SiNx (Level 2 NiCr) HCl 0.1N HNO.sub.3 0.1N H.sub.2SO.sub.4 0.1N Before After Change Before After Change Before After Change Transmitted Color Y 18.83 17.23 1.60 18.83 18.07 0.76 18.83 19.15 0.32 L* 50.49 48.55 1.94 50.49 49.58 0.91 50.49 50.86 0.37 a* 0.59 0.88 0.29 0.59 1.05 0.46 0.59 0.69 0.10 b* 3.66 3.50 0.16 3.66 3.90 0.24 3.66 3.08 0.58 E 1.97 1.05 0.70 Glass surface reflected color Y 30.70 31.31 0.61 30.70 31.51 0.81 30.70 31.10 0.40 L* 66.26 62.77 0.51 62.26 62.94 0.68 62.26 62.60 0.34 a* 3.04 2.91 0.13 3.04 2.99 0.05 3.04 2.97 0.07 b* 2.59 1.88 0.71 2.59 2.29 0.30 2.59 2.33 0.26 E 0.88 0.74 0.43 Film surface reflected color Y 53.90 59.87 5.97 53.90 57.86 3.96 53.90 58.66 4.76 L* 78.41 81.77 3.36 78.41 80.66 2.25 78.41 81.11 2.70 a* 2.23 1.67 0.56 2.23 2.42 0.19 2.23 2.18 0.05 b* 17.44 15.44 2.00 17.44 18.26 0.82 17.44 17.01 0.43 E 3.95 2.40 2.73 NaOH 0.1N NH.sub.4OH 0.5N Before After Change Before After Change Transmitted Color Y 18.83 16.62 2.21 18.83 15.14 3.69 L* 50.49 47.78 2.71 50.49 45.82 4.67 a* 0.59 0.92 0.33 0.59 0.48 0.11 b* 3.66 2.31 1.35 3.66 1.68 1.98 E 3.05 5.07 Glass surface reflected color Y 30.70 27.50 3.20 30.70 27.85 2.85 L* 62.26 59.43 2.83 62.26 59.76 2.50 a* 3.04 2.48 0.56 3.04 2.57 0.47 b* 2.59 1.07 1.52 2.59 0.67 1.92 E 3.26 3.19 Film surface reflected color Y 53.90 75.12 21.22 53.90 77.57 23.67 L* 78.41 89.45 11.04 78.41 90.58 12.17 a* 2.23 1.16 1.07 2.23 0.79 1.44 b* 17.44 9.22 8.22 17.44 6.58 10.86 E 13.81 16.37

(31) TABLE-US-00015 Test 3 - SiNx/TiOx/Nb/Tinx/SiNx (Level 1 TiOx) HCl 0.1N HNO.sub.3 0.1N H.sub.2SO.sub.4 0.1N Before After Change Before After Change Before After Change Transmitted Color Y 22.03 22.16 0.13 22.03 21.46 0.57 22.03 21.27 0.76 L* 54.06 54.20 0.14 54.06 53.45 0.61 54.06 53.24 0.82 a* 1.08 1.42 0.34 1.08 1.31 0.23 1.08 1.37 0.29 b* 4.23 4.31 0.08 4.23 4.28 0.05 4.23 4.41 0.18 E 0.38 0.65 0.89 Glass surface reflected color Y 28.50 28.47 0.03 28.50 28.78 0.28 28.50 29.68 1.18 L* 60.34 60.31 0.03 60.34 60.59 0.25 60.34 61.38 1.04 a* 3.15 3.11 0.04 3.15 3.19 0.04 3.15 3.11 0.04 b* 1.29 1.79 0.50 1.29 1.38 0.09 1.29 1.70 0.41 E 0.50 0.27 1.12 Film surface reflected color Y 47.57 49.52 1.95 47.57 52.92 5.35 47.57 49.89 2.32 L* 74.56 75.78 1.22 74.56 77.83 3.27 74.56 76.00 1.44 a* 2.70 2.48 0.22 2.70 2.70 0.00 2.70 2.24 0.46 b* 18.70 18.70 0.00 18.70 18.09 0.61 18.70 20.33 1.63 E 1.24 3.33 2.22 NaOH 0.1N NH4OH 0.5N Before After Change Before After Change Transmitted Color Y 22.03 23.51 1.48 22.03 17.62 4.41 L* 54.06 55.59 1.53 54.06 49.04 5.02 a* 1.08 1.32 0.24 1.08 0.77 0.31 b* 4.23 1.96 2.27 4.23 1. 2.38 E 2.75 5.56 Glass surface reflected color Y 28.50 22.85 5.65 28.50 26.02 2.48 L* 60.34 54.92 5.42 60.34 58.06 2.28 a* 3.15 2.62 0.53 3.15 2.60 0.55 b* 1.29 1.47 0.18 1.29 0.07 1.22 E 5.45 2.64 Film surface reflected color Y 47.57 63.23 15.66 47.57 72.04 24.47 L* 74.56 83.57 9.01 74.56 87.99 13.43 a* 2.70 1.37 1.33 2.70 0.96 1.74 b* 18.70 8.38 10.32 18.70 6.23 12.47 E 13.76 18.41

(32) TABLE-US-00016 Test 4 - SiNx/TiOx/Nb/TiNx/SiNx (Level 2 TiOx) HCl 0.1N HNO.sub.3 0.1N H.sub.2SO.sub.4 0.1N Before After Change Before After Change Before After Change Transmitted Color Y 21.70 22.97 1.27 21.70 21.27 0.43 21.70 21.09 0.21 L* 53.71 55.05 1.34 53.71 53.24 0.47 53.71 53.94 0.23 a* 1.07 1.52 0.45 1.07 1.45 0.38 1.07 1.39 0.32 b* 4.50 4.65 0.15 4.50 4.58 0.08 4.50 4.52 0.02 E 1.42 0.61 0.39 Glass surface reflected color Y 27.22 27.99 0.77 27.22 28.17 0.95 27.22 28.20 0.98 L* 59.18 59.88 0.70 59.18 60.04 0.86 59.18 60.07 0.89 a* 2.79 3.41 0.62 2.79 4.47 1.68 2.79 3.05 0.26 b* 0.44 0.10 0.34 0.44 3.05 3.49 0.44 0.35 0.09 E 2.49 1.90 1.20 Film surface reflected color Y 49.27 48.87 0.40 49.27 51.81 2.54 49.27 51.16 1.89 L* 75.62 75.37 0.25 75.62 77.17 1.55 75.62 76.78 1.16 a* 2.64 3.30 0.66 2.64 2.92 0.28 2.64 2.91 0.27 b* 18.15 20.54 2.39 18.15 19.21 1.06 18.15 18.30 0.15 E 2.49 1.90 1.20 NaOH 0.1N NH.sub.4OH 0.5N Before After Change Before After Change Transmitted Color Y 21.70 23.42 1.72 21.70 17.86 3.84 L* 53.71 55.50 1.79 53.71 49.33 4.38 a* 1.07 1.41 0.34 1.07 0.87 0.20 b* 4.50 2.53 1.97 4.50 2.09 2.41 E 2.68 5.00 Glass surface reflected color Y 27.22 22.15 5.07 27.22 25.01 2.21 L* 59.18 54.18 5.00 59.18 57.09 2.09 a* 2.79 2.50 0.29 2.79 2.54 0.25 b* 0.44 0.07 0.51 0.44 1.12 1.56 E 5.03 2.62 Film surface reflected color Y 49.27 61.67 12.40 49.27 70.71 21.44 L* 75.62 82.74 7.12 75.62 87.34 11.72 a* 2.64 1.61 1.03 2.64 1.13 1.51 b* 18.15 9.55 8.60 18.15 6.38 11.77 E 11.21 16.68

(33) The four configurations (tests 1, 2, 3 and 4) proved to be highly resistant when exposed to acids and all show very small variations in light transmittance (Y) and all color parameters (SE) are kept below 5.0 making it a stable product when submitted to etching. Furthermore, when exposed to bases, the film shows a greater resistance to NaOH 0.1N than to NH.sub.4OH 0.5N, especially in tests where NiCr was added as a protective film. NiCr tests show acceptable variations in light transmission, and transmission and reflection color parameters (E) in glass side remain below 5.0. In the film side a change in hue can be seen, due to the reaction occurring between the basic solutions and the film. No defects such as lines, pinhole or peeling of the film occurred, only the change in hue inherent to the chemical reaction with the bases, whereby it is concluded that the NiCr configurations are resistant to chemical attack from acids but slightly affectable by alkaline solutions in prolonged periods.

(34) Once the film resistance to chemical attack by immersion on tempered probes (test 1, 2, 3 and 4) was validated, an additional chemical attack test was performed according to the procedure described by ISO 9227 standard followed by the CAAS test methodology where the film is exposed to a fogging solution of 0.026% bihidrated cupric chloride and 5% sodium chloride solution. The glass sheets were exposed to the fog in a chamber at a temperature of 50 C. for 24 hours. The test results are shown below:

(35) TABLE-US-00017 Test 1 (Level 1 NiCr) Test 1 (Level 2 NiCr) Before After 4 days Change Before After 4 days Change Transmitted color Y 19.13 19.01 0.11 18.12 17.95 0.17 L* 50.83 50.70 0.13 49.63 49.43 0.20 a* 0.65 0.97 0.33 0.63 0.95 0.32 b* 3.47 3.66 0.19 3.57 3.64 0.08 E 0.40 0.39 Glass surface reflected color And 29.92 30.03 0.10 31.44 31.20 0.24 L* 61.59 61.67 0.09 62.87 62.68 0.20 a* 3.15 3.07 0.09 3.10 2.97 0.12 b* 2.47 2.64 0.17 2.23 2.30 0.06 E 0.21 0.24 Film surface reflected color Y 53.10 57.79 4.70 54.67 59.49 4.82 L* 77.93 80.56 2.63 78.85 81.49 2.64 a* 1.90 2.05 0.15 2.26 2.21 0.05 b* 16.87 16.68 0.20 17.70 17.02 0.68 E 2.64 2.73 Test 3 (Level 1 TiOx) Test 4 (Level 2 TiOx) Before After 4 days Change Before After 4 days Change Transmitted color And 21.61 20.29 1.32 21.74 21.70 0.05 L* 53.60 52.13 1.48 53.75 53.70 0.04 a* 1.01 1.28 0.26 1.12 1.43 0.31 b* 4.19 4.16 0.02 4.57 4.73 0.16 E 1.50 0.35 Glass surface reflected color Y 28.60 29.46 0.86 27.50 27.49 0.00 L* 60.43 61.18 0.75 59.43 59.43 0.00 a* 3.02 3.02 0.01 2.88 2.84 0.04 b* 1.44 1.26 0.17 0.12 0.26 0.14 E 0.77 0.15 Film surface reflected color Y 48.74 55.16 6.42 48.17 52.33 4.16 L* 75.29 78.98 3.70 74.92 77.41 2.49 a* 2.63 2.57 0.06 2.80 2.86 0.05 b* 18.45 18.58 0.12 19.19 18.77 0.42 E 3.70 2.53

(36) As in the previous cases, the four configurations (tests 1, 2, 3 and 4) are highly resistant when exposed to the 0.026% bihidrated cupric chloride and 5% sodium chloride solution since all of them show slight transmission variations and all color parameters (SE) remain below 5.0 making it a stable product under these chemical attacks conditions.

(37) To determine the level of adhesion of the film to glass, abrasion tests were performed according to the procedures described by ASTM D1044-08 standard, where a Taber device is used and a weight of 300 gr is applied on the film-coated glass sheet by rotating the device 300 times. This test was performed on the annealed substrate because the required size of the sheet is 55 cm. A glass sheet of this size cannot be tempered with conventional production equipment. All tests showed a change in transmission less than 3.0, making them highly abrasion resistant films. Samples with NiCr show a better performance in this test compared with samples including TiOx. The results of abrasion tests on annealed sheet are shown below:

(38) TABLE-US-00018 Transmittance Test 1 Test 2 Test 3 Test 4 Initial 22.32 25.56 22.93 21.26 Taber 1 22.82 25.92 23.47 23.48 Taber 2 22.66 25.89 24.07 24.45 Taber 3 22.96 25.56 23.36 23.17 Taber 4 22.78 25.64 23.09 25.16 Average 22.80 25.75 23.50 24.07 Change 0.48 0.19 0.57 2.81 % Abrasion 2.14 0.76 2.48 13.21

(39) Finally, to determine film thickness of samples 1, 2, 3 and 4, the methodology of preparation and characterization of samples for ultra-high resolution transmission electron microscope (TEM) was used, and for determining the composition energy discrimination spectroscopy (EDS) was used. The results shown in Tables 5 and 6 indicate the thicknesses of the coatings. Also the Al impurities in the Si.sub.4N.sub.3 film attributable to the type of cathode used may be seen. Non-stoichiometric ratios of materials are explained by the reactivity of the plasma with the materials.

(40) With regard to determining the thermal performance of these examples, the NFRC (National Fenestration Rating Council) methodology was used, using the Optics6 and/or Window6 software developed by Lawrence Berkeley National Laboratory, applicable to architectural and residential markets. The Model Cary 5000 spectrophotometer with Diffuse reflection accessory (DRA) was used to generate spectra.

(41) TABLE-US-00019 TABLE 5 Software Window 6 Film Thickness (nm) % R vis % R vis Solar SiyAlzNx Nb NixCry TiNx SiyAlzNx % Tuv % Tsol % Tvis Vid Pel factor EX 1 20 14 1 7 28 17.0 30.0 21.0 22.0 24.0 0.32 EX 2 20 13 5 6 28 17.0 31.0 23.0 21.0 25.0 0.31 Glass side reflected Film side Transmitted color color reflected color L* a* b* L* a* b* L* a* b* EX 1 54.3 2.1 2.3 60.4 3.8 3.2 55.3 1.4 15.5 EX 2 53.2 2.3 2.5 62.5 3.8 1.9 56.9 1.6 16.7

(42) TABLE-US-00020 TABLE 6 Software Window 6 LBNL % R % R Film Thickness (nm) % % % vis vis Solar SiyAlzNx Nb NixCry TiNx SiyAlzNx Tuv Tsol Tvis Vid Pel factor EX 3 19 1 14 7 27 17.0 30.0 22.0 22.0 23.0 0.31 Ex 4 21 10 14 7 27 18.0 31.0 18.0 24.0 26.0 0.32 Glass side reflected Transmitted color color Film side reflected color L* a* b* L* a* b* L* a b* Ex 3 54.1 2.4 2.8 61.6 3.7 2.8 54.9 2.0 17.3 Ex 4 56.3 2.2 4.3 55.5 3.7 1.6 58.0 0.7 13.7

(43) As shown in Examples 1 to 4, it is feasible to obtain an array of nanometric films applied on a glass substrate, whose function is a solar control glazing system, with mechanical strength and resistance to heat treatment characteristics.

(44) In Examples 5 and 6 the effect of the Nb film thickness in light transmission and also the adjustment of the outer hue, which can range from blue with smaller thicknesses to a silver hue, passing by neutral as the thickness increases.

(45) TABLE-US-00021 Software Window 6 Film Thickness (nm) % R vis Solar SiyAlzNx Nb NixCry TiNx SiyAlzNx % Tuv % Tsol % Tvis Vid % R vis Pel factor Ex 5 20 4 1 7 28 30.7 33.9 40.2 19.4 18.8 0.49 Ex 6 20 32 5 6 28 4.6 7.2 9.2 39.7 30.4 0.25 Glass side reflected Transmitted color color Film side reflected color L* a* b* L* a* b* L* a* b* Ex 5 69.7 2.2 2.4 51.3 3.5 4.7 50.2 0.5 8.2 Ex 6 36.3 2.1 0.6 69.2 3.3 4.1 61.3 3.2 25.4

(46) From the above, a coating on a substrate has been described with solar control properties and it will be apparent to those skilled in the art that other possible advances or improvements can be achieved, which may be considered within the field determined by the following claims.