Glazing with solar protection properties comprising a titanium oxynitride layer

Abstract

A glass article with a solar-control function includes at least one glass substrate and a stack of layers deposited on at least one face of the substrate. The stack of layers includes a layer of titanium oxynitride of general formula TiN.sub.xO.sub.y, in which 1.00<x<1.20 and in which 0.01<y<0.10. The stack of layers further includes layers of dielectric materials and optionally of metallic or nitrided layers based on chromium, nickel, titanium, niobium or a mixture of at least two of these elements.

Claims

1. A glass article with a solar-control function, the article comprising: a glass substrate; and a stack of layers deposited on at least one face of the substrate, wherein the stack of layers comprises a metallic layer comprising chromium nickel nitride (NiCrN), layers of dielectric material(s), and a layer of titanium oxynitride of formula (I) having a thickness in a range of from 10 to 80 nm,
TiN.sub.xO.sub.y  (I), wherein 1.00<x<1.20 and wherein 0.01<y<0.10, wherein the metallic layer is positioned between the layer of the titanium oxynitride and the at least face of the substrate, and wherein the metallic layer is deposited directly on the at least one face of the substrate.

2. The article of claim 1, wherein 0.02<y<0.08.

3. The article of claim 1, wherein 1.05<x<1.20.

4. The article of claim 1, wherein the thickness of the titanium oxynitride layer is in a range of from 15 to 60 nm.

5. The article of claim 1, wherein the stack further comprises, below and/or above the titanium oxynitride layer, a layer of dielectric material(s).

6. The article of claim 5, wherein the dielectric material or materials are silicon nitride, Al-doped silicon nitride, Zr-doped silicon nitride, or B-doped silicon nitride, aluminum nitride, tin oxide, a mixed oxide of zinc or tin of formula Sn.sub.yZn.sub.zO.sub.x, silicon oxide, titanium oxide, silicon oxynitride of formula SiO.sub.xN.sub.y, or a mixture of two or more of any of these.

7. The article of claim 5, wherein the layer of dielectric material(s) comprises silicon nitride and has a thickness in a range of from 25 to 80 nm.

8. The article of claim 1, wherein the stack further comprises, below and/or above the titanium oxynitride layer, a layer of a metal, wherein the metal comprises chromium, nickel, titanium, niobium, or a mixture of at least two of these elements, and wherein the layer of metal has a thickness of less than 5 nm.

9. The article of claim 8, wherein the metal is Ti, Nb, or an alloy of nickel and chromium.

10. The article of claim 1, wherein the layer of the titanium oxynitride has a thickness in a range of from 15 to 50 nm.

11. The article of claim 10, wherein the metallic layer is based on chromium nickel nitride (NiCrN).

12. The article of claim 10, wherein the layers of dielectric material(s) in the stack, altogether, have a total thickness in a range of from 10 to 100 nm.

13. The article of claim 1, wherein the stack comprises a series of layers as follows, starting from the surface of the glass substrate: the metallic layer, having a thickness in a range of from 3 to 15 nm; the layer of the titanium oxynitride; and a layer based on silicon nitride, having a thickness of from 20 to 80 nm.

14. The article of claim 1, wherein the stack comprises a series of layers as follows, starting from the surface of the glass substrate: the metallic layer, having a thickness in a range of from 3 to 15 nm; a first layer comprising silicon nitride, having a thickness in a range of from 50 to 120 nm; the layer of the titanium oxynitride; and a second layer comprising silicon nitride, having a thickness in a range of from 20 to 80 nm.

15. The article of claim 1, wherein the layers of dielectric material(s), altogether, have a total thickness in a range of from 10 to 120 nm.

16. The article of claim 1, in the form of a glazing comprising only a single glass substrate.

17. The article of claim 8, wherein the article has undergone a heat treatment.

18. The article of claim 1, which is a laminated glazing consisting of an assembly of at least two glass substrates connected together by a thermoplastic sheet.

19. The article of claim 18, wherein the thermoplastic sheet comprises polyvinyl butyral (PVB).

20. The article of claim 1, having 4 or 5 total layers.

21. The article of claim 1, wherein the metallic layer consists of NiCrN.

Description

EXAMPLE 1 (ACCORDING TO THE INVENTION)

(1) In this example according to the invention, a stack consisting of the sequence of the following layers:

(2) TABLE-US-00001 Glass /Si.sub.3N.sub.4 /TiN.sub.xO.sub.y /Si.sub.3N.sub.4 (31 nm) (19 nm) (29 nm)

(3) was deposited, according to conventional magnetron techniques, on a substrate made of Planilux® glass.

(4) The TiN.sub.xO.sub.y layer is obtained by the magnetron sputtering technique from a titanium metal target in an atmosphere very largely of nitrogen and argon, but containing an amount of oxygen of the order of 2% by volume.

(5) The silicon nitride layers are deposited according to the conventional techniques in the field, from a silicon target comprising 8% by weight of aluminum in an atmosphere of nitrogen and argon.

(6) The main characteristics of the deposition process are reported in the following table:

(7) TABLE-US-00002 Line speed (m/min) 1.7 Si.sub.3N.sub.4 Cathode power (kW) 64 Pressure (μbar) 4 Flux Ar (sccm) 700 Flux N.sub.2 (sccm) 850 TiN.sub.xO.sub.y Power (kW) 87 Pressure (μbar) 6 Flux Ar (sccm) 1600 Flux N.sub.2 + O.sub.2 (sccm) 500 Si.sub.3N.sub.4 Power (kW) 78 Pressure (μbar) 4 Flux Ar (sccm) 700 Flux N.sub.2 (sccm) 850

(8) According to the invention, the glazing thus obtained is used as single glazing or as a first substrate for obtaining a laminated glazing by lamination with another substrate made of Planilux® glass using a sheet of PVB, the stack being positioned between the two glass substrates in the final glazing.

(9) The factors T.sub.L and g were measured on the single glazing and the laminated glazing thus obtained in order to thereby determine the selectivity. The results are reported in table 1. Their colorimetric properties were also measured below. The results are reported in table 3 below.

EXAMPLE 2 (COMPARATIVE)

(10) This example was carried out in an identical manner to example 1 and a substantially identical stack was obtained, with the exception that the flow rate of nitrogen in the sputtering chamber was increased to 800 sccm, so as to increase the value of x.

(11) As for example 1, the glazing thus obtained is used as single glazing or as a first substrate for obtaining a laminated glazing by lamination with another substrate made of Planilux® glass using a sheet of PVB, the stack being positioned between the two glass substrates in the final glazing.

(12) The factors T.sub.L and g were measured on the single glazing and the a laminated glazing thus obtained in order to thereby determine the selectivity. The results are reported in table 1.

EXAMPLE 3 (ACCORDING TO THE INVENTION)

(13) In this example according to the invention, a stack consisting of the sequence of the following layers:

(14) TABLE-US-00003 Glass /Si.sub.3N.sub.4 /TiN.sub.xO.sub.y /Si.sub.3N.sub.4 (61 nm) (39 nm) (60 nm)

(15) was deposited, according to conventional magnetron techniques, on a substrate made of Planilux® glass.

(16) The TiN.sub.xO.sub.y layer is obtained by magnetron sputtering from a titanium metal target in an atmosphere very largely of nitrogen and argon, but containing an amount of oxygen of the order of 2% by volume.

(17) The main characteristics of the deposition process are reported in the following table:

(18) TABLE-US-00004 Line speed (m/min) 0.9 Si.sub.3N.sub.4 Cathode power (kW) 80 Pressure (μbar) 4 Flux Ar (sccm) 700 Flux N.sub.2 (sccm) 850 TiN.sub.xO.sub.y Power (kW) 97 Pressure (μbar) 6 Flux Ar (sccm) 1600 Flux N.sub.2 + O.sub.2 (sccm) 500 Si.sub.3N.sub.4 Power (kW) 70 Pressure (μbar) 4 Flux Ar (sccm) 700 Flux N.sub.2 (sccm) 850

(19) As for example 1, the glazing thus obtained is used as single glazing or as a first substrate for obtaining a laminated glazing by lamination with another substrate made of Planilux® glass using a sheet of PVB, the stack being positioned between the two glass substrates in the final glazing.

(20) The factors T.sub.L and g were measured on the single glazing and the laminated glazing thus obtained in order to thereby determine the selectivity. The results are reported in table 2. Their colorimetric properties were also measured below. The results are reported in table 3 below.

EXAMPLE 4 (COMPARATIVE)

(21) This example was carried out in an identical manner to example 3 and a substantially identical stack was obtained, with the exception that a greater amount of oxygen was introduced into the sputtering chamber, this amount being of the order of 5% by volume in the largely nitrogen and argon atmosphere.

(22) As for the preceding examples, the glazing thus obtained is used as single glazing (S) or as a first substrate for obtaining a laminated glazing (F) by lamination with another substrate made of Planilux® glass using a sheet of PVB, the stack being positioned between the two glass substrates in the final glazing.

(23) The factors T.sub.L and g were measured on the single glazing and the laminated glazing thus obtained in order to thereby determine the selectivity. The results are reported in table 2.

EXAMPLE 5 (COMPARATIVE)

(24) In this example, use was made of a glazing from the applicant company sold under the reference Cool-Lite ST120, the stack of which comprises a layer of niobium nitride as layer that reflects/absorbs solar radiation, surrounded by two silicon nitride layers.

(25) The factors T.sub.L and g were measured on these glazings, under the same conditions as above, in order to thereby determine the selectivity. The results are reported in table 2.

(26) As for example 1, the glazing thus obtained is used as single glazing (S) or as a first substrate for obtaining a laminated glazing (F) by lamination with another substrate made of Planilux® glass using a sheet of PVB, the stack being positioned between the two glass substrates in the final glazing.

(27) The factors T.sub.L and g were measured on the single glazing and the laminated glazing thus obtained in order to thereby determine the selectivity. The results are reported in table 2.

(28) The values of x and y in the titanium oxynitride layers are measured conventionally by XPS (X-ray photoelectron spectroscopy) techniques on a Nova-Kratos machine according to the following conditions:

(29) Analysis Conditions:

(30) Source: monochromatized Al Kα

(31) 300 Watts for particular spectra

(32) Area analyzed: 110×110 μm.sup.2 (μspot mode)

(33) Detection angle: normal (θ=0°)

(34) Depth analyzed less than 10 nm in normal detection

(35) Abrasion Conditions:

(36) Ions: Ar—2.0 keV

(37) Sweep: 3×3 mm.sup.2 centered on the analysis zone

(38) Abrasion cycles/time per cycle: 30 cycles of 1 minute.

(39) The characteristics of the various glazings obtained for examples 1 and 2, measured according to the standards specified above, are reported in table 1 below:

(40) TABLE-US-00005 TABLE 1 Example 1 Example 2 Glazing type S* F* S* F* Functional TiN.sub.xO.sub.y TiN.sub.xO.sub.y layer x 1.16 1.16 1.20 1.20 y 0.03 0.03 0.03 0.03 T.sub.L (%) 49.1 49.7 46.7 48.6 g (%) 45.8 44.9 45.4 45.6 Selectivity 1.07 1.11 1.03 1.07 (T.sub.L/g) Emissivity 45 N.A. 45 N.A. (%) *S: single glazing - F: laminated glazing * N.A.: not applicable

(41) TABLE-US-00006 TABLE 2 Example 3 Example 4 Example 5 Glazing S* F* S* F* S* F* type Functional TiN.sub.xO.sub.y TiN.sub.xO.sub.y NbN layer x 1.16 1.16 1.16 1.16 N.A. N.A. y 0.03 0.03 0.1 0.1 N.A. N.A. T.sub.L (%) 32.1 28.9 37.8 34.3 21.0 21.0 g (%) 29.8 30.9 34.7 34.7 30.0 29.5 Selectivity 1.08 0.93 1.09 0.95 0.70  0.71 (T.sub.L/g) Emissivity 26 N.A. 40 N.A. 64 N.A. (%) *S: single glazing - F: laminated glazing *N.A.: not applicable

(42) The comparison of the data reported in tables 1 and 2 shows that a greater selectivity is obtained when the stack in question comprises a functional layer having a nitrogen content x that is in accordance with the invention, as shown by the comparison of examples 1 and 2, whereas the best emissivity, i.e. the lowest, is obtained for lower oxygen contents, as shown by the comparison of examples 3 and 4. The present invention enables the optimization of these two parameters, high selectivity and low emissivity. In particular, the applicant company has been able to show, through the examples reported in the present application, that in such titanium oxynitride layers the very precise control of the composition of said layer, in particular of the values of x and y, made it possible to optimize both the selectivity and the emissivity of the glazing.

(43) The colorimetric characteristics of the glazing according to example 1 and according to example 3, in the (CIE L*b*a*) international system, were also measured in transmission and in external reflection (exterior side). The substrate equipped with its stack was also subjected to a heat treatment consisting in heating at 650° C. for several minutes followed by a tempering. This treatment is representative of the conditions undergone by the glazing if the latter has to be tempered or else bent.

(44) All the optical data are reported in table 3 below:

(45) TABLE-US-00007 TABLE 3 Light transmission Exterior reflection T.sub.L g T.sub.L/g a*.sub.T b*.sub.T R.sub.Lext a*.sub.Rext b*.sub.Rext Example 1 Single glazing 49.1 45.8 1.07 −2.2 −2.8 10.9 −2.2 −9.5 Tempered 55.2 48.3 1.14 −2.4 0.9 12.9 −3.8 −13.2 single glazing Laminated glazing 49.7 44.9 1.11 −3.4 −2 10.9 0.9 −0.1 Example 3 Single glazing 32.1 29.8 1.08 −2.9 8.8 21.3 −2.2 7.0 Tempered 40.4 33.2 1.2 −4.6 9.1 19.7 4.0 −0.6 single glazing Laminated glazing 28.9 30.9 0.93 −4.5 2.8 17.4 1.1 3.3

(46) The data reported in table 3 show the ideal colorimetric properties in transmission and in exterior reflection of glazings equipped with stacks according to the invention: In transmission, the parameters a*.sub.T and b*.sub.T remain relatively low, providing a relatively neutral color in transmission. In reflection, the parameter a*.sub.ext according to the glazings according to the invention is relatively low and often negative, whereas the parameter b* is close to 0 for the laminated glazings (neutral color in reflection), i.e. highly negative for the single glazing according to example 1, which provides a blue color of the glazing as desired in exterior view.

(47) Such colorimetric properties therefore result in a neutral or blue-green color of the glazings in transmission but above all in exterior reflection, as is currently desired in the building field.

(48) According to another advantage, the solar-control stacks according to the present invention, the active layer(s) of which are based on a titanium oxynitride, are extremely simple to manufacture, in particular by the cathode sputtering vacuum deposition technique referred to as magnetron sputtering.

(49) Moreover, supplementary durability tests have shown that such layers could easily be deposited on face 2 of a single glazing, without risk of degradation thereof, by chemical action (moisture) or by mechanical action (abrasion of the stack).

EXAMPLE 6 (ACCORDING TO THE INVENTION)

(50) In this example according to the invention, it is sought to obtain a glass article according to the invention having a high exterior light reflection while preserving a good selectivity, and also a neutral colorimetry in exterior reflection as desired in the building field.

(51) For this, a stack consisting of the sequence of the following layers:

(52) TABLE-US-00008 Glass /NiCrN /TiN.sub.xO.sub.y /Si.sub.3N.sub.4 (8 nm) (13 nm) (52 nm)

(53) was deposited, according to conventional magnetron techniques, on a substrate made of Planilux® glass.

(54) The TiN.sub.xO.sub.y layer is obtained by the magnetron sputtering technique from a titanium metal target in an atmosphere largely of nitrogen and argon, but containing an amount of oxygen of the order of 2% by volume. Values of x=1.18 and y=0.07 in the TiN.sub.xO.sub.y titanium oxynitride layer are measured conventionally by the XPS techniques described above.

(55) The silicon nitride layers are deposited according to the conventional techniques in the field, from a silicon target comprising 8% by weight of aluminum in an atmosphere of nitrogen and argon.

(56) The NiCrN layer is deposited from the sputtering of an NiCr target in an argon and nitrogen atmosphere, the elements Ni and Cr being present in the target in the following proportions: 80 wt % of Ni and 20 wt % of Cr.

(57) The main characteristics of the deposition process are reported in the following table:

(58) TABLE-US-00009 Line speed (m/min) 2 NiCrN Cathode power (kW) 19 Pressure (μbar) 3.5 Flux Ar (sccm) 1150 Flux N.sub.2 (sccm) 600 TiN.sub.xO.sub.y Power (kW) 92 Pressure (μbar) 6 Flux Ar (sccm) 1600 Flux N.sub.2 + O.sub.2 (sccm) 500 Si.sub.3N.sub.4 Power (kW) 150 Pressure (μbar) 4 Flux Ar (sccm) 700 Flux N.sub.2 (sccm) 850

(59) According to the invention, the glazing thus obtained can be used as single glazing or as a first substrate for obtaining a laminated glazing by lamination with another substrate made of Planilux® glass using a sheet of PVB, the stack being positioned between the two glass substrates in the final glazing.

(60) The factors T.sub.L and g were measured on the single glazing and the laminated glazing thus obtained in order to thereby determine the selectivity and their colorimetric properties. The results are reported in the tables below.

EXAMPLE 7 (ACCORDING TO THE INVENTION)

(61) In this example according to the invention, another stack consisting of the sequence of the following layers:

(62) TABLE-US-00010 Glass /NiCrN /Si.sub.3N.sub.4 /TiN.sub.xO.sub.y /Si.sub.3N.sub.4 (6 nm) (93 nm) (25 nm) (46 nm)

(63) was deposited, according to conventional magnetron techniques, on a substrate made of Planilux® glass.

(64) The TiN.sub.xO.sub.y, NiCrN and Si.sub.3N.sub.4 layers are obtained according to the same principles as disclosed above.

(65) Values of x=1.13 and y=0.07 in the TiN.sub.xO.sub.y titanium oxynitride layer are measured conventionally by the XPS techniques described above.

(66) The main characteristics of the deposition process are reported in the following table:

(67) TABLE-US-00011 Line speed (m/min) 1.3 NiCrN Cathode power (kW) 12.5 Pressure (μbar) 3.5 Flux Ar (sccm) 1150 Flux N.sub.2 (sccm) 600 Si.sub.3N.sub.4 Cathode power (kW) 150 Pressure (μbar) 4 Flux Ar (sccm) 700 Flux N.sub.2 (sccm) 850 TiN.sub.xO.sub.y Cathode power (kW) 80 Pressure (μbar) 6 Flux Ar (sccm) 1600 Flux N.sub.2 + O.sub.2 (sccm) 500 Si.sub.3N.sub.4 Cathode power (kW) 90 Pressure (μbar) 4 Flux Ar (sccm) 700 Flux N.sub.2 (sccm) 850

(68) In the same way as for the preceding example, the glazing thus obtained is used as single glazing or as a first substrate for obtaining a laminated glazing by lamination with another substrate made of Planilux® glass using a sheet of PVB, the stack being positioned between the two glass substrates in the final glazing.

(69) The factors T.sub.L and g were measured on the single glazing and the laminated glazing thus obtained in order to thereby determine the selectivity and their colorimetric properties. The results are reported in the tables below.

EXAMPLE 8 (COMPARATIVE)

(70) In this example, use was made of a glazing from the applicant company sold under the reference Cool-Lite STB120, the stack of which comprises a layer of niobium nitride as layer that reflects/absorbs solar radiation, surrounded by two silicon nitride layers.

(71) The factors T.sub.L and g were measured on the single glazing and the laminated glazing thus obtained in order to thereby determine the selectivity and their colorimetric properties. The results are reported in the tables below.

(72) The selectivity characteristics of the various glazings obtained, measured according to the specified standards, are reported in table 4 below:

(73) TABLE-US-00012 TABLE 4 Example 6 Example 7 Example 8 R.sub.Lext Single 31 21 21 glazing Laminated 31 21 21 glazing T.sub.L (%) Single 33 27 22 glazing Laminated 31 26 22 glazing g (%) Single 33 31 32 glazing Laminated 33 32 33 glazing Selectivity Single 1.00 0.88 0.66 (T.sub.L/g) glazing Laminated 0.94 0.80 0.67 glazing

(74) The comparison of the data reported in table 4 shows that a greater selectivity is obtained for a stack comprising the two layers in accordance with the present invention, i.e. for the stack from examples 6 and 7, and which is even equal to 1 for the stack according to example 6, despite the presence of the highly reflective layer made of NiCrN.

(75) The colorimetric characteristics of the glazing according to examples 6 to 8 were also measured in the (CIE L*b*a*) international system in transmission and in external reflection (exterior side).

(76) All the optical data are reported in table 5 below:

(77) TABLE-US-00013 TABLE 5 LIGHT TRANSMISSION EXTERIOR REFLECTION Example T.sub.L a*.sub.T b*.sub.T R.sub.Lext a*.sub.Rext b*.sub.Rext Example 6 Single glazing 33 −2.5 2.5 31 −2.5 −1.0 Laminated glazing 31 −2.7 2.7 31 −2.5 −0.8 Example 7 Single glazing 27 −4.0 0.0 21 −4.0 −18.0 Laminated glazing 26 −3.6 −2.5 21 −0.5 −18.0 Example 8 Single glazing 22 −1.4 0.5 21 −2.9 −16 Laminated glazing 22 −1.4 2.7 21 −3.6 −10.8

(78) The data reported in table 5 show the ideal colorimetric properties in transmission and in exterior reflection of the glazings equipped with stacks according to the invention: In transmission, the parameters a*.sub.T and b*.sub.T are usually negative and remain relatively low, providing a relatively neutral color in transmission. In reflection, the parameter a*.sub.Rext according to the glazings according to the invention is always relatively low and usually negative, whereas the parameter b*.sub.Rext is either close to 0 for example 6, which provides a neutral color in reflection, or highly negative (example 7), which provides a blue color in reflection as desired in the building field.

(79) Such colorimetric properties therefore result in a neutral color of the glazings in transmission and a neutral (example 6) or blue (example 7) color in exterior reflection, as currently desired in the building field.

(80) According to another advantage, the solar-control stacks according to the present are extremely simple to manufacture, in particular by the cathode sputtering vacuum deposition technique referred to as magnetron sputtering.

(81) Moreover, supplementary durability tests have shown that such layers could easily be deposited on face 2 of a single glazing, without risk of degradation thereof, by chemical action (moisture) or by mechanical action (abrasion of the stack).