Solar control glazing
A sheet of vitreous material bearing a multilayer solar control lamination that includes at least one functional layer based on a material that reflects infrared radiation surrounded by dielectric coatings and at least one 4 nm thick absorbent layer formed by at least one oxide or oxynitride of a cobalt- and/or copper-based alloy. The sheet of vitreous material may be applied to solar control glazing units having multiple glazings.
1. A sheet of vitreous material bearing a multilayer solar control lamination, said lamination comprising:
a functional layer;
a dielectric coating below the functional layer;
a dielectric coating above the functional layer; and
an absorbent layer,
wherein the functional layer comprises a material that reflects infrared radiation,
wherein the absorbent layer has a thickness of at least 4 nm,
wherein the absorbent layer comprises at least one oxide or oxynitride of an alloy comprising at least 20 atom % cobalt and/or copper, and
wherein the alloy comprises cobalt-tin, cobalt-titanium, copper-aluminium, cobalt-chromium, copper-zinc, copper-tin, copper-cobalt, copper-titanium, cobalt-copper, or mixtures thereof.
2. The sheet of vitreous material according to claim 1 , wherein when the multilayer solar control lamination is deposited onto a clear soda-lime float glass sheet 6 mm thick, the solar factor SF of the coated sheet is less than 45% and the light transmission L T is less than 70%.
3. The sheet of vitreous material according to claim 1 , wherein the alloy comprises at least 40 atom % of cobalt or copper.
4. The sheet of vitreous material according to claim 1 , wherein the absorbent layer comprises one or more of the following oxides: CuAlOx, CuZnOx, CoSnOx, CoTiOx, CuTiOx and CuSnOx.
5. The sheet of vitreous material according to claim 1 , wherein the absorbent layer comprises one or more of the following oxides: CoCuOx, CoCrOx and CoCrTiOx.
6. The sheet of vitreous material according to claim 1 , wherein the absorbent layer has a thickness of 10 to 80 nm.
7. The sheet of vitreous material according to claim 1 , wherein the functional layer is silver-based.
8. The sheet of vitreous material according to claim 1 , wherein the multilayer solar control lamination comprises at least two silver-based functional layers.
9. The sheet of vitreous material according to claim 1 , wherein the sheet of vitreous material bearing a multilayer solar control lamination has undergone a toughening and/or bending high-temperature thermal treatment.
10. The sheet of vitreous material according to claim 1 , wherein at least one dielectric coating is a zinc-tin mixed oxide-based layer containing at least 20% tin.
11. The sheet of vitreous material according to claim 1 , wherein a lower dielectric coating arranged between the sheet of vitreous material and the functional layer is a zinc-tin mixed oxide layer containing at least 20% tin, and an outermost dielectric coating is also a zinc-tin mixed oxide layer containing at least 20% tin.
12. The sheet of vitreous material according to claim 1 , wherein the dielectric coating below the functional layer comprises a zinc oxide-based layer, optionally doped with aluminium, said zinc oxide-based layer being in direct contact with the functional layer.
13. The sheet of vitreous material according to claim 1 , wherein the dielectric coating below the functional layer comprises a zinc-tin mixed oxide-based layer that does not contain more than about 20% tin and which comprises at least about 80% zinc, said zinc-tin mixed oxide-based layer being in direct contact with the functional layer.
14. The sheet of vitreous material according to claim 1 , wherein the dielectric coating below the functional layer comprises a zinc-tin mixed oxide-based layer that does not comprise more than about 10% tin and comprises at least about 90% zinc, said zinc-tin mixed oxide-based layer being in direct contact with the functional layer.
15. The sheet of vitreous material according to claim 1 , wherein values a* and b* in reflection on the vitreous material side are such that −5<a*<0 and −15<b*<0.
16. The sheet of vitreous material according to claim 1 , wherein the absorbent layer is obtained by cathodic sputtering of a ceramic target formed from the corresponding mixed oxide.
17. The sheet of vitreous material according to claim 1 , wherein after a high-temperature thermal treatment the sheet of vitreous material bearing a multilayer solar control lamination has a variation in tint ΔE* not exceeding the value of 2.
18. The sheet of vitreous material according to claim 1 , wherein the lamination comprises three functional layers, all located between dielectric coatings and comprising a material that reflects infrared radiation.
19. The sheet of vitreous material according to claim 1 , wherein the sheet of vitreous material bearing a multilayer solar control lamination has a selectivity higher than 1.5.
20. A multiple glazing comprising at least one sheet of vitreous material according to claim 1 .
21. The multiple glazing according to claim 20 , wherein the sheet of vitreous material bearing a multilayer solar control lamination has a solar factor equal to or less than 35% and a light reflection less than 18%.
22. The multiple glazing according to claim 20 , wherein the sheet of vitreous material bearing a multilayer solar control lamination has a solar factor equal to or less than 28%.
23. The multiple glazing according to claim 20 , wherein the sheet of vitreous material bearing a multilayer solar control lamination has a light transmission less than 55%.