Heat treatable low-E coated articles and methods of making same

• US 6,686,050 B2
• Filed: 01/07/2003
• Issued: 02/03/2004
• Est. Priority Date: 07/10/2000
• Status: Expired due to Term

• Current Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Original Assignee: Centre Luxembourgeois de Recherches pour le Verre et la Ceramique SA, Guardian Industries Corporation (KOCH Industries Incorporated)
• Inventors: Lingle, Philip J., Laird, Ronald E., Lemmer, Jean-Marc, Dietrich, Anton
• Primary Examiner(s): Jones, Deborah
• Assistant Examiner(s): PIZIALI, ANDREW T
• Application Number:
  US10/337,384
• Publication Number:
  US 20030194570A1
• Time in Patent Office: 392 Days
• Field of Search: 428/428, 428/432, 428/448, 428/469, 428/472, 428/689, 428/697, 428/699, 428/701, 428/702
• US Class Current: 40/638
• CPC Class Codes: B32B 17/10009 characterized by the number, the constitution or treatment of glass sheets
• CPC Class Codes: B32B 17/10036 comprising two outer glass sheets
• CPC Class Codes: B32B 17/10174 Coatings of a metallic or dielectric material on a constituent layer of glass or polymer
• CPC Class Codes: B32B 17/10761 containing vinyl acetal
• 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 17/3639 Multilayers containing at least two functional metal layers
• 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 17/3694 one layer having a composition gradient through its thickness
• CPC Class Codes: C03C 2217/78 Coatings specially designed to be durable, e.g. scratch-resistant
• CPC Class Codes: C23C 14/0015 characterized by the colour of the layer
• CPC Class Codes: C23C 14/0084 Producing gradient compositions
• CPC Class Codes: C23C 14/0652 Silicon nitride
• CPC Class Codes: C23C 14/08 Oxides C23C14/10 takes precedence
• CPC Class Codes: C23C 14/562 for coating elongated substrates
• CPC Class Codes: C23C 14/568 Transferring the substrates through a series of coating stations C23C14/562 takes precedence
• CPC Class Codes: Y10T 428/12458 : having composition, density, or hardness gradient
• CPC Class Codes: Y10T 428/12847 : Cr-base component
• CPC Class Codes: Y10T 428/12896 : Ag-base component
• CPC Class Codes: Y10T 428/12944 : Ni-base component

Abstract

A heat treatable coated article (e.g., vehicle windshield, IG unit, etc.) is provided with a dual-silver low-E coating. Before and/or after heat treatment (HT), the coating and/or coated article has a visible transmittance of at least 70%, more preferably at least 75%. Moreover, the coating and/or coated article is designed so as to have approximately the same color when viewed over a wide range of viewing angles. In certain embodiments, at least one contact layer (e.g., of or including NiCrO_x) that contacts an infrared (IR) reflecting layer (e.g., Ag) is oxidation graded so that it progressively becomes less oxidized through its thickness as it nears the IR reflecting layer. In still other embodiments, a Si-rich silicon nitride layer(s) may be utilized to reduce haze.

Claims

1. A coated article comprising:

a coating provided on a glass substrate, said coating comprising;

a) at least one dielectric layer;

b) a first contact layer;

c) a first IR reflecting layer;

d) a second contact layer, said first IR reflecting layer contacting each of said first and second contact layers;

e) at least one dielectric layer;

f) a third contact layer;

g) a second IR reflecting layer;

h) a fourth contact layer, said second IR reflecting layer contacting each of said third and fourth contact layers;

i) at least one dielectric layer;

wherein after being heat treated (HT) said coated article has a visible transmittance of at least 70%, a T_solar no greater than 50%, an R_solar of at least 26%, and a sheet resistance (R_s) of no greater than 8.0 ohms/sq; and

wherein said a) at least one dielectric layer comprises Si-rich Si_xN_y where x/y is from 0.76 to 1.5.

2. The coated article of claim 1, wherein x/y is from 0.85 to 1.2.

3. The coated article of claim 2, wherein said coated article has a haze value of no greater than 0.40 after heat treatment.

4. The coated article of claim 3, wherein said silicon nitride inclusive layer has an index of refraction “

n”

of at least 2.05.

5. The coated article of claim 4, wherein said silicon nitride inclusive layer has an index of refraction “

n”

of at least 2.07.

6. The coated article of claim 1, wherein at least two of said first, second, third and fourth contact layers comprise Ni or a Ni alloy.

7. The coated article of claim 6, wherein said at least two of said first, second, third and fourth contact layer comprise an oxide of NiCr.

8. The coated article of claim 7, wherein said at least two contact layers comprising an oxide of NiCr are each oxidation graded so that a first portion of each of said at least two layers close to an adjacent IR reflecting layer is less oxidized than a second portion of said layer that is further from said IR reflecting layer than said first portion.

9. A coated article comprising:

a layer system supported by a class substrate, the layer system comprising from the substrate outwardly;

a Si-rich silicon nitride Si_xN_y layer where x/y is from 0.76 to 1.5 in at least part of the layer;

a first contact layer; and

an IR reflecting layer.

10. The coated article of claim 9, wherein x/y is from 0.85 to 1.2 in the entire layer.

11. The coated article of claim 9, wherein the Si-rich silicon nitride Si_xN_y layer has an index of refraction “

n”

of at least about 2.05 and an extinction coefficient “

k”

of at least about 0.001.

12. The coated article of claim 11, wherein the Si-rich silicon nitride Si_xN_y layer has an index of refraction “

n”

of at least about 2.08 and an extinction coefficient “

k”

of at least about 0.003.

13. The coated article of claim 9, wherein the layer system further comprises at least a titanium dioxide layer located between said substrate and said Si-rich silicon nitride Si_xN_y layer.

14. The coated article of claim 9, wherein said first contact layer comprises an oxide of NiCr and said IR reflecting layer comprises Ag.

15. The coated article of claim 14, further comprising a second contact layer comprising an oxide of NiCr over said IR reflecting layer, and at least a dielectric layer over the second contact layer.

16. The coated article of claim 9, further comprising another Si-rich silicon nitride Si_xN_y layer where x/y is from 0.76 to 1.5 positioned over said IR reflecting layer, wherein at least one layer is provided between said another Si-rich silicon nitride Si_xN_y layer and said IR reflecting layer.

17. The coated article of claim 16, further comprising another IR reflecting layer provided over said another Si-rich silicon nitride Si_xN_y layer.

18. A coated article including a glass substrate and a layer system supported by the glass substrate, the layer system comprising:

a Si-rich silicon nitride Si_xN_y layer where x;

y is from 0.76 to 1.50 in at least part of the silicon nitride layer;

an oxidation graded NiCr oxide inclusive layer deposited on and in contact with said Si-rich silicon nitride layer, wherein said oxidation graded layer is more oxidized at an interface with said silicon nitride layer than at another portion of said oxidation graded layer.

19. The article of claim 18, further comprising a layer comprising silver in contact with said oxidation graded layer.

20. The article of claim 19, wherein x:

y is from 0.85 to 1.20 in the Si-rich silicon nitride layer.

21. A coated article including a glass substrate and a layer system supported by the glass substrate, the layer system comprising:

a layer comprising silver;

a Si-rich silicon nitride Si_xN_y layer where x;

y is from 0.76 to 1.50 in at least part of the silicon nitride layer; and

wherein the Si-rich silicon nitride layer is located between at least the layer comprising silver and the glass substrate.

22. The coated article of claim 21, wherein x:

y is from 0.85 to 1.2.

23. The coated article of claim 21, wherein the coated article is heat treated.

24. The coated article of claim 21, wherein Si-rich silicon nitride layer has an index of refraction “

n”

of at least 2.05.