Low-E coated articles and methods of making same
View Patent ↗In certain example embodiments, low-E coated articles may be designed so as to realize a combination of good visible transmission (T vis ) and an excellent solar heat gain coefficient (SHGC), thereby realizing an improved (i.e., higher) T vis /SHGC ratio. In certain example embodiments of this invention, if heat treated (HT), the low-E coated articles may have approximately the same color characteristics as viewed by the naked eye both before and after heat treatment (i.e., a low ΔE* value) in certain example instances. Such coated articles may be used in insulating glass (IG) units, windows, and/or other suitable applications.
1. An insulating glass (IG) window unit comprising:
first and second glass substrates coupled to each other proximate their respective edges so as to form an insulating space therebetween;
a layer system supported by one of the glass substrates proximate the insulating space, said layer system comprising an infrared (IR) reflecting layer comprising silver located between at least first and second dielectric layers which are silicon nitride inclusive layers, wherein said layer system includes only one IR reflecting layer comprising silver;
wherein the IG window unit has a visible transmission (T vis ) of 47-60%, a SHGC of no greater than 0.36, and a T vis /SHGC ratio of at least 140; and
wherein said layer system comprises the following recited layers with the following thickness ranges:
first silicon nitride inclusive layer: 230-320 Å thick
first Ni and/or NiCr inclusive layer: 10-40 Å thick
the IR reflecting layer comprising silver: 125-180 Å thick
second Ni and/or NiCr inclusive layer: 10-40 Å thick
second silicon nitride inclusive layer: 450-560 Å thick;
wherein the first silicon nitride inclusive layer is located between the glass substrate and the first Ni and/or NiCr inclusive layer.
2. The IG window unit of claim 1 , wherein the IG window unit has a T vis /SHGC ratio of at least 145.
3. The IG window unit of claim 1 , wherein the IG window unit has a T vis /SHGC ratio of at least 150.
4. The IG window unit of claim 1 , wherein the IG window unit has a T vis /SHGC ratio of at least 153.
5. The IG window unit of claim 1 , wherein the IG window unit has a visible transmission (T vis ) of 49-56%.
6. The IG window unit of claim 1 , wherein the IG window unit has an SHGC of no greater than 0.35.
7. The IG window unit of claim 1 , wherein the IG window unit has an SHGC of no greater than 0.34.
8. The IG window unit of claim 1 , wherein the glass substrate with the layer system thereon is heat treated, and the heat treated glass substrate and layer system have a ΔE* value (glass side reflective) of no greater than 3.0 after or due to heat treatment of the glass substrate with the layer system thereon.
9. The IG window unit of claim 1 , wherein the glass substrate with the layer system thereon is heat treated, and the heat treated glass substrate and layer system have a ΔE* value (glass side reflective) of no greater than 2.5 after or due to heat treatment of the glass substrate with the layer system thereon.
10. The IG window unit of claim 1 , wherein the glass substrate with the layer system thereon is heat treated, and the heat treated glass substrate and layer system have a ΔE* value (glass side reflective) of no greater than 2.0 after or due to heat treatment of the glass substrate with the layer system thereon.
11. The IG window unit of claim 1 , wherein said layer system has a sheet resistance value R s no greater than 7 ohms/square.
12. The IG window unit of claim 1 , wherein said layer system has a sheet resistance value R s no greater than 5 ohms/square.
13. The IG window unit of claim 1 , wherein each of said first and second layers Ni and/or NiCr inclusive layers is substantially metallic and is at least about 15 angstroms (Å) thick.
14. The IG window unit of claim 1 , wherein the IR reflecting layer comprising silver is from about 135-170 angstroms thick.
15. A coated article comprising:
a coating supported by a glass substrate, said coating comprising an infrared (IR) reflecting layer comprising silver located between at least first and second dielectric layers comprising silicon nitride, wherein said coating includes only one IR reflecting layer comprising silver;
wherein the coated article measured monolithically has a visible transmission (T vis ) of 50-65%, a SHGC of no greater than 0.41, and a T vis /SHGC ratio of at least 140;and
wherein said coated article comprises the following recited layers moving away from the glass substrate with the following thickness ranges:
the first dielectric layer comprising silicon nitride: 230-320 Å thick
a first layer comprising Ni and/or NiCr: 10-40 Å thick
the IR reflecting layer comprising silver: 125-180 Å thick
a second layer comprising Ni and/or NiCr: 10-40 Å thick
the second dielectric layer comprising silicon nitride: 450-560 Å thick.
16. The coated article of claim 15 , wherein the coated article has a monolithic T vis /SHGC ratio of at least 145.
17. The coated article of claim 15 , wherein the coated article has a monolithic T vis /SHGC ratio of at least 148.
18. The coated article of claim 15 , wherein the coated article has a monolithic visible transmission (T vis ) of 53-61%.
19. The coated article of claim 15 , wherein the coated article has an SHGC of no greater than 0.39.
20. The coated article of claim 15 , wherein the coated article is heat treated and has a ΔE* value (glass side reflective) of no greater than 3.0 after or due to heat treatment.
21. The coated article of claim 15 , wherein the coated article is heat treated and has a ΔE* value (glass side reflective) of no greater than 2.5 after or due to heat treatment.
22. An IG window unit including at least the coated article of claim 15 .
23. An insulating glass (IG) window unit comprising:
first and second glass substrates coupled to each other proximate their respective edges so as to form an insulating space therebetween;
a layer system supported by said first glass substrate proximate the insulating space, said layer system comprising an infrared (IR) reflecting layer comprising silver located between at least first and second dielectric layers comprising silicon nitride, wherein said layer system includes only one IR reflecting layer comprising silver;
wherein the IG window unit has a visible transmission (T vis ) of 47-60%, a SHGC of no greater than 0.36, and a T vis /SHGC ratio of at least 140; and
wherein said layer system comprises the following recited layers moving away from the first glass substrate with the following thickness ranges:
the first dielectric layer comprising silicon nitride: 150-900 Å thick
a first layer comprising Ni and/or NiCr: 10-80 Å thick
the IR reflecting layer comprising silver: 90-200 Å thick
a second layer comprising Ni and/or NiCr: 10-80 Å thick
the second dielectric layer comprising silicon nitride: 400-600 Å thick.