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

• US 6,576,349 B2
• Filed: 02/28/2001
• Issued: 06/10/2003
• 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., Lemmer, Jean-Marc, Dietrich, Anton, Laird, Ronald E.
• Primary Examiner(s): Jones, Deborah
• Assistant Examiner(s): Piziali, Andrew T
• Application Number:
  US09/794,224
• Publication Number:
  US 20020064662A1
• Time in Patent Office: 832 Days
• Field of Search: 428/426, 428/428, 428/432, 428/469, 428/472, 428/673, 428/697, 428/698, 428/699, 428/701, 428/702, 428/610
• US Class Current: 428/610
• 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 heat treated coated article including a coating supported by a glass substrate, the coating comprising:

an infrared reflecting layer contacting and sandwiched between first and second layers, said second layer comprising an oxide of NiCr; and

wherein at least said second layer comprising the oxide of NiCr is oxidation graded so that a first portion of said second layer closer to said infrared reflecting layer is less oxidized than a second portion of said second layer that is further from said infrared reflecting layer;

wherein the second layer comprising the oxide of NiCr that is oxidation graded is sandwiched between and contacts each of the infrared reflecting layer and a nitride layer.

2. The coated article of claim 1, wherein said infrared reflecting layer comprises silver.

3. The coated article of claim 1, wherein said first portion of said second layer comprising the oxide of NiCr is from 0 to 40% oxidized, and said second portion of said second layer comprising the oxide of NiCr is at least about 50% oxidized.

4. The coated article of claim 3, wherein said first portion of said second layer comprising the oxide of NiCr is from 0 to 20% oxidized.

5. The coated article of claim 3, wherein said first portion of said second layer comprising the oxide of NiCr is from 0 to 20% oxidized, and said second portion of said second layer comprising the oxide of NiCr is at least about 60% oxidized.

6. The coated article of claim 1, wherein said second layer comprising the oxide of NiCr becomes progressively less oxidized through its thickness as it nears said IR reflecting layer.

7. The coated article of claim 1, wherein said first portion of said second layer comprising the oxide of NiCr is conductive or semi-conductive, and said second portion of said second layer comprising the oxide of NiCr is dielectric.

8. The coated article of claim 1, wherein both of said first and second layers comprise an oxide of NiCr and are oxidation graded so that each of said first and second layers comprises a first portion close to said infrared reflecting layer being less oxidized than a second portion further from said infrared reflecting layer than said first portion.

9. The coated article of claim 1, wherein said coating comprises, from the glass substrate outwardly, the following layers:

at least one dielectric layer;

said first layer comprising an oxide of NiCr;

said infrared reflecting layer;

said second layer comprising the oxide of NiCr;

at least one additional dielectric layer;

a third layer comprising an oxide of NiCr;

a second infrared reflecting layer;

a fourth layer comprising an oxide of NiCr; and

at least one additional dielectric layer.

10. The coated article of claim 9, wherein said infrared reflecting layers comprise silver, and wherein said at least one dielectric layer between said substrate and said first layer comprising the oxide of NiCr comprises silicon nitride.

11. The coated article of claim 9, wherein said coated article has a visible transmittance of at least about 70%, an R_solar of at least 26%, and a sheet resistance after heat treatment of no greater than 8.0 ohms/sq.

12. The coated article of claim 11, wherein said coated article has a visible transmittance of at least about 75%, an R_solar of at least 28%, and a sheet resistance after heat treatment of no greater than 6.0 ohms/sq.

13. The coated article of claim 1, wherein said second layer is provided between said infrared reflecting layer and said substrate.

14. The coated article of claim 1, wherein said infrared reflecting layer is provided between said second layer and said substrate.

15. A heat treated coated article including a coating supported by a substrate, the coating comprising:

an infrared reflecting layer sandwiched between first and second layers, said second layer comprising an oxide of Ni;

wherein at least said second layer comprising an oxide of Ni is oxidation graded and becomes progressively more oxidized through its thickness proceeding further from said infrared reflecting layer; and

wherein the second layer comprising an oxide of Ni, that is oxidation graded, is sandwiched between and contacting the infrared reflecting layer and a nitride layer.

16. The coated article of claim 15, wherein said second layer comprises an oxide of NiCr.

17. The coated article of claim 15, wherein said infrared reflecting layer comprises metallic silver.

18. The coated article of claim 15, wherein a first portion of said second layer closer to said infrared reflecting layer is from 0 to 40% oxidized, and a second portion of said second layer further from said infrared reflecting layer is at least about 50% oxidized.

19. The coated article of claim 18, wherein said first portion is from 0 to 20% oxidized, and said second portion is at least about 60% oxidized.

20. The coated article of claim 15, wherein both of said first and second layers comprise an oxide of NiCr and are oxidation graded so that each of said first and second layers comprises a first portion close to said infrared reflecting layer being less oxidized than a second portion further from said infrared reflecting layer than said first portion.

21. The coated article of claim 15, wherein said coating comprises the following layers:

at least one dielectric layer;

said first layer;

said infrared reflecting layer;

said second layer comprising an oxide of Ni;

at least one additional dielectric layer;

a third layer comprising an oxide of Ni;

a second infrared reflecting layer;

a fourth layer comprising an oxide of Ni; and

at least one additional dielectric layer.

22. A heat treated coated article including a coating supported by a substrate, the coating comprising:

a metallic infrared reflecting layer contacting and sandwiched between first and second contact layers;

wherein at least said second contact layer is oxidation graded and becomes progressively more oxidized through its thickness proceeding further from said infrared reflecting layer; and

wherein said second contact layer, that is oxidation graded, is sandwiched between and contacting the metallic infrared reflecting layer and a nitride layer.

23. The coated article of claim 22, wherein said coated article has a visible transmittance of at least about 70%, an R_solar of at least 26%, and a sheet resistance after heat treatment of no greater than 8.0 ohms/sq.

24. The coated article of claim 23, wherein said coated article further comprises a second metallic infrared reflecting layer contacting and sandwiched between third and fourth contact layers, at least one of said third and fourth contact layers being oxidation graded so as to become progressively more oxidized through its thickness proceeding further from said second metallic infrared reflecting layer.

25. The coated article of claim 24, wherein said first and second infrared reflecting layers each comprise silver.

26. The coated article of claim 22, wherein said second contact layer comprises an oxide of NiCr, wherein a first portion of said second contact layer is closer to said infrared reflecting layer than a second portion of said second contact layer, and wherein said first portion is from 0 to 40% oxidized, and said second portion is at least about 50% oxidized so as to be more transmissive to visible light than said first portion.

27. The coated article of claim 25, wherein said coating comprises, from the substrate outwardly, the following layers:

at least one dielectric layer;

said first contact layer;

said infrared reflecting layer comprising Ag;

said second contact layer;

at least one additional dielectric layer;

said third contact layer;

said second infrared reflecting layer comprising Ag;

said fourth layer contact layer, this layer being oxidation graded; and

at least one additional dielectric layer.

28. The coated article of claim 27, wherein said at least one dielectric layer between said substrate and said first contact layer comprises at least a silicon nitride layer.

29. The coated article of claim 27 wherein said coated article has a visible transmittance of at least about 75%, an R_solar of at least 28%, and a sheet resistance after heat treatment of no greater than 6.0 ohms/sq.

30. A heat treated coated article comprising a glass substrate supporting a coating, the coating comprising:

at least first and second dielectric layers;

a layer comprising Ag;

a layer comprising NiCr, wherein the layer comprising NiCr and the layer comprising Ag are provided between at least the first and second dielectric layers;

wherein the layer comprising NiCr is more oxidized at a location further from the layer comprising Ag than at a location closer to the layer comprising Ag; and

wherein the layer comprising NiCr, that is more oxidized at a location further from the layer comprising Ag than at a location closer to the layer comprising Ag, is sandwiched between and contacting said layer comprising Ag and one of said dielectric layers which comprises a nitride.

31. The coated article of claim 30, wherein the first and second dielectric layers comprise silicon nitride.

32. The coated article of claim 30, wherein the layer comprising Ag is provided at a location between the glass substrate and the layer comprising NiCr.

33. The coated article of claim 30, wherein the layer comprising NiCr is at least about 50% oxidized at the location further from the layer comprising Ag and from 0-40% oxidized at the location closer to the layer comprising Ag.

34. The coated article of claims 30, wherein the coating has a sheet resistance of no greater than 8.0 ohms/square.

35. The coated article of claim 30, wherein the coated article further comprises another layer comprising Ag, and has a visible transmittance of at least 70%.

36. A heat treated coated article comprising a glass substrate supporting a coating, the coating comprising:

first and second layers comprising Ag;

a layer comprising NiCr located between the first and second layers comprising Ag, the layer comprising NiCr being closer to the first layer comprising Ag than to the second layer comprising Ag;

wherein the layer comprising NiCr is more oxidized at a location further from the first layer comprising Ag than at a location closer to the first layer comprising Ag; and

wherein the layer comprising NiCr, that is more oxidized at a location further from the first layer comprising Ag than at a location closer to the first layer comprising Ag, is sandwiched between and contacting each of the first layer comprising Ag and a layer comprising silicon nitride.

37. The coated article of claim 36, wherein the coating has a sheet resistance of no greater than 8.0 ohms/square.

38. The coated article of claim 36, wherein the coated article has a visible transmittance of at least 70%.

39. The coated article of claim 36, further comprising a layer comprising silicon nitride located between the substrate and the layers comprising Ag.

40. The coated article of claim 36, wherein the coating further comprises a layer comprising titanium oxide that contacts a layer comprising silicon nitride.

41. A heat treated coated article comprising a glass substrate supporting a coating, the coating comprising:

first and second layers comprising Ag;

a layer comprising NiCr that is closer to the first layer comprising Ag than to the second layer comprising Ag;

wherein the layer comprising NiCr is more oxidized at a location further from the first layer comprising Ag than at a location closer to the first layer comprising Ag; and

wherein the layer comprising NiCr, that is more oxidized at a location further from the first layer comprising Ag than at a location closer to the first layer comprising Ag, is sandwiched between and contacting the first layer comprising Ag and a layer comprising a nitride.

42. The coated article of claim 41, wherein the coating has a sheet resistance of no greater than 8.0 ohms/square.

43. The coated article of claim 41, wherein the coated article has a visible transmittance of at least 70%.

44. The coated article of claim 41, further comprising a layer comprising silicon nitrate located between the substrate and the layers comprising Ag.

45. The coated article of claim 41, wherein the coating further comprises a layer comprising titanium oxide that contacts a layer comprising silicon nitrate.

46. A heat treated coated article including a coating supported by a glass substrate, the coating comprising:

first and second layers comprising Ag, the first layer comprising Ag being located closer to the glass substrate than the second layer comprising Ag;

first, second and third layers comprising silicon nitride, wherein the first layer comprising silicon nitride is located between the glass substrate and the first layer comprising Ag, wherein the second layer comprising silicon nitride is located between the first and second layers comprising Ag, and wherein the third layer comprising silicon nitride is located over both of the first and second layers comprising Ag;

a contact layer that is in direct contact with one of the layers comprising Ag, wherein the contact layer comprises at least one metal and is more oxidized at a location further from the layer comprising Ag that it contacts than at a location closer to the layer comprising Ag that it contacts; and

wherein the contact layer, in addition to contacting one of the layers comprising Ag, also contacts one of the layers comprising silicon nitride on an opposite side thereof.

47. The coated article of claim 46, wherein the contact layer comprises an oxide of Ni and/or Cr.

48. A heat treated coated article including a coating supported by a substrate, the coating comprising:

a layer comprising Ag contacting and sandwiched between first and second contact layers; and

wherein at least said second contact layer comprises a metal and is more oxidized at a location further from said layer comprising Ag than at a location closer to said layer comprising Ag, and wherein said second contact layer is sandwiched between and contacting the layer comprising Ag and a nitride layer.

49. The coated article of claim 48, wherein the coated article is thermally tempered.

50. The coated article of claim 48, wherein the second contact layer, that comprises a metal and is more oxidized at a location further from said layer comprising Ag than at a location closer to said layer comprising Ag, comprises an oxide of Ni.

51. The coated article of claim 48, wherein the second contact layer, that comprises a metal and is more oxidized at a location further from said layer comprising Ag than at a location closer to said layer comprising Ag, comprises an oxide of Cr.

52. The coated article of claim 48, wherein the nitride layer comprises silicon nitride.