Low-E matchable coated articles and methods of making same

• US 20020009601A1
• Filed: 02/08/2001
• Published: 01/24/2002
• Est. Priority Date: 12/06/1999
• Status: Active Grant

• Current Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Original Assignee: Guardian Industries Corporation (KOCH Industries Incorporated)
• Inventors: Stachowiak, Grzegorz
• Granted Patent: US 6,495,263 B2
• Time in Patent Office: Days
• US Class Current: 428/432
• CPC Class Codes: C03C 17/36 at least one coating being a metal
• CPC Class Codes: C03C 17/3618 Coatings of type glass/inorganic compound/other inorganic layers, at least one layer being metallic
• CPC Class Codes: C03C 17/3626 one layer at least containing a nitride, oxynitride, boronitride or carbonitride
• CPC Class Codes: C03C 17/3644 the metal being silver
• CPC Class Codes: C03C 17/3652 the coating stack containing at least one sacrificial layer to protect the metal from oxidation
• CPC Class Codes: C03C 17/366 Low-emissivity or solar control coatings
• CPC Class Codes: C03C 17/3681 the multilayer coating being used in glazing, e.g. windows or windscreens
• CPC Class Codes: C03C 2217/78 Coatings specially designed to be durable, e.g. scratch-resistant
• CPC Class Codes: Y10T 428/12542 More than one such component
• CPC Class Codes: Y10T 428/12576 Boride, carbide or nitride component
• CPC Class Codes: Y10T 428/12896 Ag-base component
• CPC Class Codes: Y10T 428/12944 Ni-base component
• CPC Class Codes: Y10T 428/265 1 mil or less

Abstract

A heat treatable coated article including an infrared (IR) reflecting layer (e.g., of or including Ag), the coated article being able to attain a ΔE*_ab (glass side) no greater than about 3.0, more preferably no greater than 2.5, and even more preferably no greater than 2.0, following or due to heat treatment (e.g., thermal tempering). Accordingly, low-E (i.e., low emissivity) coated articles of certain embodiments of this invention appear from the glass side thereof visually similar to the naked eye both before and after heat treatment. Coated articles herein may be used in the context of insulating glass (IG) window units, vehicle windshields, or any other suitable applications. In certain embodiments of this invention, an exemplary layer stack includes: glass/Si₃N₄/NiCr/Ag/NiCr/Si₃N₄. Other materials may instead be used without departing from the scope and/or spirit of the instant invention which is a low-E matchable product.

Claims

1. A coated article comprising:

a layer system supported by a glass substrate, said layer system comprising an infrared (IR) reflecting silver layer located between first and second dielectric layers; and

wherein said coated article has a Δ

E*_ab value (glass side) no greater than 3.0 after or due to heat treatment.

2. The coated article of claim 1, wherein said coated article has a Δ

E*_ab value (glass side) no greater than 2.5 following or due to thermal tempering of the coated article.

3. The coated article of claim 1, wherein said coated article has a Δ

E*_ab value (glass side) no greater than 2.0 following or due to thermal tempering of the coated article, and

wherein said coated article has a color characterized by a*_G and b*_G color coordinate values of the coated article both being negative both before and after heat treatment of the coated article.

4. The coated article of claim 1, wherein said layer system further includes a first layer including Ni or NiCr located between said silver layer and said first dielectric layer, and a second layer including Ni or NiCr located between said silver layer and said second dielectric layer.

5. The coated article of claim 4, wherein said coated article has a Δ

a*_G value (glass side, absolute value) no greater than 1.0 after or due to heat treatment.

6. The coated article of claim 5, wherein said coated article has a Δ

a*_G value (glass side, absolute value) no greater than 0.8 after or due to heat treatment.

7. The coated article of claim 1, wherein said coated article has a hemispherical emissivity (E_h) of no greater than 0.25, both before and after heat treatment.

8. The coated article of claim 4, wherein said coated article has a hemispherical emissivity (E_h) of no greater than 0.20, both before and after heat treatment.

9. The coated article of claim 4, wherein said coated article has a sheet resistance value R_S no greater than 20 ohms/square before heat treatment.

10. The coated article of claim 9, wherein said coated article has a sheet resistance value R_S no greater than 15 ohms/square, both before and after heat treatment.

11. The coated article of claim 10, wherein said coated article has a sheet resistance value R_S no greater than 12 ohms/square, both before and after heat treatment.

12. The coated article of claim 4, wherein said first and second dielectric layers comprise silicon nitride.

13. The coated article of claim 12, wherein each of said first and second Ni or NiCr inclusive layers is at least 20 angstroms (Å

) thick.

14. The coated article of claim 13, wherein said layer system comprises the recited layers at the following thicknesses, where the first silicon nitride inclusive layer is located between the glass substrate and the first Ni or NiCr inclusive layer:

first silicon nitride inclusive layer;

300-350 thick

first Ni or NiCr inclusive layer;

20-50 thick

silver layer;

60-100 thick

second Ni or NiCr inclusive layer;

20-50 thick

second silicon nitride inclusive layer;

400-500 thick.

15. The coated article of claim 14, wherein said layer system comprises the recited layers at the following thicknesses:

first silicon nitride inclusive layer;

310-330 thick

first Ni or NiCr inclusive layer;

25-45 thick

silver layer;

60-80 thick

second Ni or NiCr inclusive layer;

25-45 thick

second silicon nitride inclusive layer;

420-480 thick.

16. The coated article of claim 1, wherein the coated article makes up a portion of an insulating glass (IG) window unit.

28. The coated article of claim 1, wherein the coated article has an a*_G value of from about 0.0 to −

4.0 before and after heat treatment, and a b*_G value that is negative both before and after heat treatment.

29. The coated article of claim 28, wherein the coated article has an a*_G value of from about 0.0 to −

2.5 before and after heat treatment.

17. A coated article comprising:

a substrate;

a layer system provided on the substrate, said layer system comprising from the glass outwardly, a first silicon nitride inclusive layer, a first Ni or NiCr inclusive layer, an IR reflecting metal layer, a second Ni or NiCr inclusive layer, and a second silicon nitride inclusive layer;

wherein each of said first and second Ni or NiCr inclusive layers is at least about 20 Å

thick; and

wherein said coated article has a hemispherical emissivity (E_h) of no greater than 0.25 before heat treatment, a sheet resistance R_S no greater than 20 ohms/square before heat treatment, and a Δ

E*_ab value (glass side) no greater than 2.5 after or due to heat treatment.

18. The coated article of claim 17, wherein said coated article has a Δ

E*_ab value (glass side) no greater than 2.0 following thermal tempering of the coated article.

19. The coated article of claim 17, wherein said coated article has a color characterized by a*_G and b*_G color coordinate values of the coated article both being negative both before and after heat treatment of the coated article.

20. The coated article of claim 17, wherein said coated article has a Δ

a*_G value (glass side, absolute value) no greater than 1.0 after or due to heat treatment.

21. The coated article of claim 20, wherein said coated article has a Δ

a*_G value (glass side, absolute value) no greater than 0.8 after or due to heat treatment.

22. The coated article of claim 17, wherein said IR reflecting metal layer comprises silver.

23. A method of making a coated article, the method comprising:

depositing a layer system on a glass substrate, the layer system including an infrared (IR) reflecting metal layer located between first and second dielectric layers, wherein prior to heat treatment the glass substrate with the layer system thereon has a sheet resistance R_S no greater than 20 ohms/square; and

heat treating the substrate with the layer system thereon so that due to said heat treating the resulting substrate with the layer system thereon has a Δ

E*_ab value (glass side) no greater than 2.5.

24. The method of claim 23, wherein said heat treating comprises thermally tempering the substrate with the layer system thereon.

25. The method of claim 23, wherein said depositing comprises sputtering.

26. The method of claim 23, wherein the layer system comprises, from the substrate outwardly at the following thicknesses:

a) first silicon nitride inclusive layer;

300-350 thick

b) first Ni or NiCr inclusive layer;

20-50 thick

c) silver layer;

60-100 thick

d) second Ni or NiCr inclusive layer;

20-50 thick

e) second silicon nitride inclusive layer;

400-500 thick.

27. A method of making a coated article, the method comprising:

sputtering a layer system onto a glass substrate to form a coated substrate, the layer system comprising a metal infrared (IR) reflecting layer located between first and second dielectric layers; and

thermally tempering the coated substrate including the glass substrate with the layer system thereon, so that the coated substrate has a Δ

E*_ab value (glass side) no greater than 2.5 and a hemispherical emissivity (E_h) no greater than 0.25.

30. A coated article comprising:

a glass substrate;

a layer system provided on the substrate, said layer system comprising from the glass outwardly, a first silicon nitride inclusive layer 300 to 350 Å

thick, a first Ni or NiCr inclusive layer from 25 to 45 Å

thick, a silver layer from 60-100 Å

thick, a second Ni or NiCr inclusive layer from 25 to 45 Å

thick, and a second silicon nitride inclusive layer; and

wherein said coated article has a hemispherical emissivity (E_h) of no greater than 0.25 and a sheet resistance R_S no greater than 20 ohms/square.

31. The coated article of claim 30, wherein the coated article is heat treated and has a Δ

E*_ab value (glass side) no greater than 2.5.