Optical coating with improved durability
View Patent ↗The invention discloses optical coatings with improved durability, the coating comprising a durability enhancing layer, a nucleation layer and an infrared reflecting layer. The invention also discloses methods of making thin film layers having enhanced durability.
1. An optical coating on a substrate, the coating comprising, in order outward from the substrate,
a first dielectric layer;
a durability enhancement layer comprising an oxide or oxynitride of zirconium disposed directly on the first dielectric layer;
a subcomposite multilayer comprising
i) a nucleation layer including Zn;
ii) an infrared reflecting layer;
iii) a barrier layer; and
optionally,
a second dielectric layer.
2. The coating of claim 1 , wherein the durability enhancement layer is in contact with the nucleation layer.
3. The coating of claim 1 , wherein the coating is heat-treated or tempered.
4. The coating of claim 3 , wherein the coating has an optical haze that is less than about 0.6% after being heat-treated or tempered.
5. The coating of claim 3 , wherein the coating has improved mechanical durability as compared to a coating that does not comprise a durability enhancement layer.
6. The coating of claim 1 , wherein the first dielectric layer comprises an oxide or oxynitride layer of titanium.
7. The coating of claim 1 , wherein the nucleation layer comprises an oxide of zinc.
8. The coating of claim 1 , wherein the infrared reflecting layer comprises silver, gold, copper, a nitride of titanium, a nitride of zirconium, nickel-chromium or combinations thereof.
9. The coating of claim 1 , wherein the coating comprises at least one topcoat comprising an oxide, nitride or oxynitride of silicon or zirconium, or combinations thereof.
10. A window unit comprising the optical coating of claim 1 , wherein the window unit is an insulated glass unit, a monolithic glass unit, a vehicular glass unit, or an architectural glass unit.
11. The coating of claim 1 , wherein the first and second dielectric layers do not contain Zr.
12. The coating of claim 1 , further comprising one or more additional subcomposite multilayers.
13. A method of making an optical thin layer film having enhanced durability, said method comprising depositing on a substrate the coating of claim 1 .
14. The coating of claim 1 , wherein the durability enhancement layer is about 2 nm to about 10 nm thick.
15. The coating of claim 14 , wherein the durability enhancement layer is about 4 nm to about 8 nm thick.