Substrate provided with a stack having thermal properties

Abstract

A material includes a transparent substrate coated on one face with a stack of thin layers successively including, starting from the face, an alternation of three silver-based functional metal layers denoted, starting from the substrate, first, second and third functional layers respectively Ag1, Ag2 and Ag3, and of four dielectric coatings denoted, starting from the substrate, M1, M2, M3 and M4, with optical thicknesses respectively To1, To2, To3 and To4. Each functional metal layer is positioned between two dielectric coatings. The geometrical thickness of the second functional layer Ag2 is less than the thickness of the first functional layer Ag1. The geometrical thickness of the second functional layer Ag2 is less than the thickness of the third functional layer Ag3. The dielectric coating M2 exhibits a lower optical thickness To2 than the optical thicknesses To1, To3 and To4 respectively of the dielectric coatings M1, M3 and M4.

Claims

1. A material comprising: a transparent substrate coated on one face with a stack of thin layers successively comprising, starting from said face, an alternation of three silver-based functional metal layers denoted, starting from the substrate, first, second and third functional layers respectively Ag1, Ag2 and Ag3, and of four dielectric coatings denoted, starting from the substrate, M1, M2, M3 and M4, with optical thicknesses To1, To2, To3 and To4, respectively, wherein dielectric coating M1 includes all dielectric layers arranged between the transparent substrate and the first functional layer Ag1, dielectric coating M2 includes all dielectric layers arranged between the first functional layer Ag1 and the second functional layer Ag2, dielectric coating M3 includes all dielectric layers arranged between the second functional layer Ag2 and the third functional layer Ag3, and dielectric coating M4 includes all dielectric layers arranged above the third functional layer Ag3, and wherein a geometrical thickness of the second functional layer Ag2 is 5 to 10 nm and is less than a geometrical thickness of the first functional layer Ag1, wherein the second functional layer Ag2 is continuous, the geometrical thickness of the second functional layer Ag2 is less than a geometrical thickness of the third functional layer Ag3, the dielectric coating M2 exhibits a lower optical thickness To2 than each of the optical thicknesses To1, To3 and To4, and no dielectric coating M1, M2, M3 and M 4 contains tin.

2. The material as claimed in claim 1, in which the optical thickness To2 of said dielectric coating M2 is between 40 and 90 nm.

3. The material as claimed in claim 1, in which the geometrical thickness of said first functional layer Ag1 is between 10 and 18 nanometers, and the geometrical thickness of said third functional layer Ag3 is between 10 and 18 nanometers.

4. The material as claimed in claim 1, in which the cumulative geometrical thickness of said functional layers Ag1, Ag2 and Ag3 is between 25 and 50 nanometers.

5. The material as claimed in claim 1, in which said dielectric coating M3 exhibits a greater optical thickness To3 than each of the optical thicknesses To1 and To4.

6. The material as claimed in claim 1, in which To2<To4<To1<To3.

7. The material as claimed in claim 1, in which To3>1.5 To2.

8. The material as claimed in claim 1, in which To3>1.5 To4.

9. The material as claimed in claim 1, in which To3>1.5 To1.

10. The material as claimed in claim 1, in which: To1 is between 75 and 120 nm, To2 is between 50 and 70 nm, To3 is between 130 and 190 nm and To4 is between 70 and 110 nm.

11. The material as claimed in claim 1, in which the ratio of the geometrical thickness of the first functional layer Ag1 to the geometrical thickness of the second functional layer Ag2 is greater than 1.3 and/or the ratio of the geometrical thickness of the third functional layer Ag3 to the geometrical thickness of the second functional layer Ag2 is greater than 1.3.

12. The material as claimed in claim 1, in which the geometrical thickness of the third functional layer Ag3 is greater than the geometrical thickness of the first functional layer Ag1.

13. The material as claimed in claim 1, in which the stack additionally comprises at least one blocking layer located in contact with a functional metal layer.

14. A glazing comprising: the material as claimed in claim 1.

15. The glazing as claimed in claim 14, wherein the glazing is a monolithic, laminated or multiple glazing.

16. The material as claimed in claim 1, in which the stack additionally comprises at least one blocking layer located in contact with a functional metal layer and each functional layer is in contact with a blocking layer located above the functional layer.

17. The material as claimed in claim 1, in which said stack comprises, starting from the transparent substrate: the first dielectric coating M1 comprises at least one dielectric layer having a barrier function and one dielectric layer having a stabilizing function, optionally a blocking layer, the first functional layer Ag1, optionally a blocking layer, the second dielectric coating M2 comprises at least one lower dielectric layer having a stabilizing function, one dielectric layer having a barrier function and one upper dielectric layer having a stabilizing function, optionally a blocking layer, the second functional layer Ag2, optionally a blocking layer, the third dielectric coating M3 comprises at least one lower dielectric layer having a stabilizing function, one dielectric layer having a barrier function and one upper dielectric layer having a stabilizing function, optionally a blocking layer, the third functional layer Ag3, optionally a blocking layer, and the fourth dielectric coating M4 comprises at least one dielectric layer having a stabilizing function, one dielectric layer having a barrier function and optionally one protective layer.

18. The material as claimed in claim 1, in which one or more of dielectric coatings M1, M2 and M3 consists of optionally-doped zinc oxide.

19. The material as claimed in claim 1, in which dielectric coating M2 consists of optionally-doped zinc oxide.

20. A material comprising: a transparent substrate coated on one face with a stack of thin layers successively comprising, starting from said face, an alternation of three silver-based functional metal layers denoted, starting from the substrate, first, second and third functional layers respectively Ag1, Ag2 and Ag3, and of four dielectric coatings denoted, starting from the substrate, M1, M2, M3 and M4, with optical thicknesses To1, To2, To3 and To4, respectively, wherein dielectric coating M1 includes all dielectric layers arranged between the transparent substrate and the first functional layer Ag1, dielectric coating M2 includes all dielectric layers arranged between the first functional layer Ag1 and the second functional layer Ag2, dielectric coating M3 includes all dielectric layers arranged between the second functional layer Ag2 and the third functional layer Ag3, and dielectric coating M4 includes all dielectric layers arranged above the third functional layer Ag3, and wherein the dielectric coating M2 exhibits a lower optical thickness To2 than each of the optical thicknesses To1, To3 and To4, one or more of dielectric coatings M1, M2, M3 and M 4 consists of optionally-doped zinc oxide, a geometrical thickness of the second functional layer Ag2 is 5 to 10 nm and is less than a geometrical thickness of the first functional layer Ag1, wherein the second functional layer Ag2 is continuous, the geometrical thickness of the second functional layer Ag2 is less than a geometrical thickness of the third functional layer Ag3, the geometrical thickness of said first functional layer Ag1 is between 10 and 16 nanometers, and the geometrical thickness of said third functional layer Ag3 is between 10 and 18 nanometers.

Description

(1) The details and advantageous characteristics of the invention emerge from the following nonlimiting examples, illustrated by means of the appended FIGURE.

(2) The proportions between the various components are not observed in order to make the FIGURE easier to read.

(3) FIG. 1 illustrates a stack structure according to the invention comprising three functional metal layers 40, 80, 120, this structure being deposited on a transparent glass substrate 10. Each functional layer 40, 80, 120 is positioned between two dielectric coatings 20, 60, 100, 140 so that: the first functional layer 40 starting from the substrate is positioned between the dielectric coatings 20, 60, the second functional layer 80 is positioned between the dielectric coatings 60, 100 and the third functional layer 120 is positioned between the dielectric coatings 100, 140.

(4) These dielectric coatings 20, 60, 100, 140 each comprise at least one dielectric layer 24, 28; 62, 64, 68; 102, 104, 108; 142, 144.

(5) The stack can also comprise: blocking underlayers 30, 70 located in contact with a functional layer, blocking overlayers 50, 90 and 130 located in contact with a functional layer, a protective layer 160, for example made of TiZr or of titanium zirconium oxide.

EXAMPLES

(6) I. Preparation of the Substrates: Stacks, Deposition Conditions

(7) Stacks of thin layers defined below are deposited on substrates made of clear soda-lime glass with a thickness of 6 mm.

(8) In the examples of the invention: the functional layers are silver (Ag) layers, the blocking layers are metal layers made of an alloy of nickel and of chromium (NiCr), the barrier layers are based on silicon nitride, doped with aluminum (Si.sub.3N.sub.4:Al), the stabilizing layers are made of zinc oxide doped with aluminum (ZnO).

(9) The conditions for deposition of the layers, which were deposited by sputtering (“magnetron cathode” sputtering), are summarized in table 1.

(10) TABLE-US-00001 TABLE 1 Target Deposition n at employed pressure Gas 550 nm Si.sub.3N.sub.4 Si:Al at 92:8 3.2 × 10.sup.−3 55% Ar/ 2.03 (% by weight) mbar (Ar + N.sub.2) ZnO Zn:Al at 98:2 1.8 × 10.sup.−3 63% Ar/ 1.95 (% by weight) mbar (Ar + O.sub.2) SnZnO Zn:68 Sn:30 Sb: 3.7 × 10.sup.−3 59% Ar/ 2.04 2 (% by weight) mbar (Ar + O.sub.2) NiCr Ni (80 at. %); 2-3 × 10.sup.−3 100% Ar — Cr (20 at. %) mbar Ag Ag 3 × 10.sup.−3 100% Ar — mbar At. = atomic

(11) Table 2 lists the materials and the physical thicknesses in nanometers (unless otherwise indicated) of each layer and the corresponding optical thickness (in nanometers) of each dielectric coating as a function of their position with regard to the substrate carrying the stack (final line at the bottom of the table).

(12) TABLE-US-00002 TABLE 2 Layer No. in figure Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 1 (inv) (inv) (comp) (comp) (comp) To of the dielectric 140 75 75 51 79 84 coating M4 with: Tp (ZnO) 144 8 8 NA NA NA Tp (Si.sub.3N.sub.4:Al) 142 28.5 28.5 NA NA NA Tp (NiCr) 130 1 0.2 — — 0.1 (blocking layer) Tp (Ag3) 120 14.5 13.8 13 22 15.5 (functional layer) To of the dielectric 100 169 153 100 125 170 coating M3 with: Tp (ZnO) 110 8 8 NA NA NA Tp (SnZnO) 108 8 8 NA NA NA Tp (Si.sub.3N.sub.4:Al) 104 58 50 NA NA NA Tp (ZnO) 102 8 8 NA NA NA NiCr 90 1.0 0.1 — — 0.6 (blocking layer) Tp (Ag2) 80 8.0 5.0 11 6.5 15.8 (functional layer) Tp (NiCr) 70 4.0 0.1 — — o (blocking layer) To of the dielectric 60 59 60 160 115 115 coating M2 with: Tp (ZnO) 68 8 8 NA NA NA Tp (Si.sub.3N.sub.4:Al) 64 13 13.8 NA NA NA Tp (ZnO) 62 8 8 NA NA NA Tp (NiCr) 50 1.0 0.1 — — 0.1 (blocking layer) Tp (Ag1) 40 10.5 15.8 14 8 7 (functional layer) Tp (NiCr) 30 1.0 0.4 — — — (blocking layer) To of the dielectric 20 82 94 89 65 116 coating M1 with: Tp (ZnO) 28 8 8 NA NA NA Tp (Si.sub.3N.sub.4:Al) 24 32 37.8 NA NA NA Glass substrate (mm) 10 6 6 6 6 6 *Tp: Physical thickness (nm); To: Optical thickness (nm).

(13) Examples 1 and 2 are examples according to the invention. Comparative examples 3 and 4 are examples as described in the international patent application No. WO2011/147875. Comparative example 5 is in accordance with example 1 of the international patent application No. WO2017/006030.

(14) II. “Solar Control” and Colorimetry Performance Qualities

(15) Table 3 lists the main optical characteristics measured when the stacks form part of a double glazing of 6/16/4 structure: (ext.) 6-mm glass/16-mm interlayer space filled with 90% argon/4-mm glass (int.), the stack been positioned on face 2 (the face 1 of the glazing being the outermost face of the glazing, as usual).

(16) For these double glazings: T.sub.L indicates: the light transmission in the visible region in %, measured according to the illuminant D65 at 2° Observer; a*.sub.T and b*.sub.T indicate the colors in transmission a* and b* in the L*a*b* system, measured according to the illuminant D65 at 2° Observer and measured perpendicularly to the glazing; R.sub.Lext indicates: the light reflection in the visible region in %, measured according to the illuminant D65 at 2° Observer on the side of the outermost face, the face 1; a*.sub.Rext and b*.sub.Rext indicate the colors in reflection a* and b* in the L*a*b* system, measured according to the illuminant D65 at 2° Observer on the side of the outermost face and measured thus perpendicularly to the glazing; R.sub.Lint indicates: the light reflection in the visible region in %, measured according to the illuminant D65 at 2° Observer on the side of the interior face, the face 4; a*.sub.Rint and b*.sub.Rint indicate the colors in reflection a* and b* in the L*a*b* system, measured according to the illuminant D65 at 2° Observer on the side of the interior face and measured thus perpendicularly to the glazing.

(17) TABLE-US-00003 TABLE 3 Target Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 value (inv) (inv) (comp) (comp) (comp) Solar factors ≤30% 30% 29% 30% 28% 25% “g” Selectivity “s” ≈2% 1.8 1.8 2.0 2.0 2.0 T.sub.L % >50.0% 53.2 55.5 59.8 54.8 50.0 a*.sub.T <0 −4.0 −4.4 −5.3 −7.5 −5 b*.sub.T <3 1 2.7 2.9 3.8 4.5 R.sub.Lext % >25 30 26 13 18 30 a*.sub.Rext <0 −0.8 −3.5 −4.8 −3 −1 b*.sub.Rext <0 −1.5 −6.7 −10.1 −7.3 −4 R.sub.Lint % — 27.5 22.2 15.8 21.5 26 a*.sub.Rint <0 −6.0 −9.7 −0.6 7.7 −4 b*.sub.Rint <0 −0.9 −10.3 1.1 −3.3 −6.4

(18) According to the invention, it is possible to produce a glazing comprising a stack having three functional metal layers with exhibits a shiny silver appearance in reflection on the external side, a light transmission of greater than 50%, a high selectivity, a high light reflection and a low solar factor.

(19) The examples according to the invention all exhibit a pleasant and subdued coloration in transmission, preferably within the range of the blues or blue-greens.

(20) It is seen, with regard to the data given in table 3, that the glazings according to the invention (examples 1 and 2) simultaneously exhibit a solar factor of less than or equal to 30% for a selectivity of slightly less than 2. In addition, these glazings exhibit an external reflection at least greater than 25%, combined with a low and negative value of the factors a*.sub.Rext and b*.sub.Rext, making it possible to obtain the desired “shiny” effect. These glazings also have neutral colors in transmission or alternatively a slightly blue-green hue.