Coated article with low-E coating including IR reflecting layer(s) and corresponding method

• US 20060046072A1
• Filed: 09/01/2004
• Published: 03/02/2006
• Est. Priority Date: 09/01/2004
• Status: Active Grant

• 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: Thomsen, Scott V., Lemmer, Jean-Marc, Muller, Jens-Peter, Ferreira, Jose
• Granted Patent: US 7,217,461 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 17/3639 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

Abstract

A coated article is provided with a low-emissivity (low-E) layer stack for use in a window unit or the like. The layer stack, or coating, may permit the coated article to achieve one or more of a low solar factor (SF) value, a high selectivity (T_vis/SF) value, substantially neutral color at normal and/or off-axis viewing angles, and/or low emissivity. When high selectivity values are achieved, there is provided a high ratio of visible transmission to SF, which is a desirable feature in certain example instances. In certain example embodiments, a sub-oxide layer (e.g., NiCrO_x) may be used as a contact layer under an infrared (IR) reflecting layer in order to permit low SF values, high selectivity, and good coloration to be achieved.

Claims

1. An insulating glass (IG) window unit comprising:

first and second glass substrates, and a coating supported by one of the substrates, the coating comprising;

at least one layer comprising silver sandwiched between and contacting first and second contact layers, wherein the first contact layer is located below said layer comprising silver and is oxided to a lesser extent than is the second contact layer located above said layer comprising silver; and

wherein the IG window unit has a visible transmission of from 40 to 60%, a selectivity (T_vis/SF) of at least 1.75, and a solar factor (SF) of no greater than 27.5.

2. The IG window unit of claim 1, wherein the first contact layer comprises an oxide of Ni and/or Cr.

3. The IG window unit of claim 1, wherein each of the first and second contact layers comprise an oxide of Ni and/or Cr.

4. The IG window unit of claim 1, wherein the coating includes only two infrared (IR) reflecting layers comprising silver.

5. The IG window unit of claim 1, wherein each of the first and second contact layers comprise an oxide of NiCr.

6. The IG window unit of claim 1, wherein the IG window unit has a selectivity of at least 1.80.

7. The IG window unit of claim 1, wherein the IG window unit has a selectivity of at least 1.85.

8. The IG window unit of claim 1, wherein the IG window unit has a SF of no greater than 27.0.

9. The IG window unit of claim 1, wherein the IG window unit has an outside reflective a* value, at a normal viewing angle, of from −

3 to +2.

10. The IG window unit of claim 1, wherein the IG window unit has an outside reflective a* value, at a normal viewing angle, of from −

2.5 to +1.

11. The IG window unit of claim 1, wherein the coating has a sheet resistance (R_s) of no greater than 3.0 ohms/square.

12. The IG window unit of claim 1, wherein the coating has a sheet resistance (R_s) of no greater than 2.0 ohms/square.

13. The IG window unit of claim 1, wherein the glass substrate supporting the coating is not heat treated with the coating thereon.

14. The IG window unit of claim 1, wherein the IG window unit has a visible transmission of from about 45 to 55%.

15. The IG window unit of claim 1, wherein the IG unit has an outside a* value which does not change by more than 3.5 given a viewing angle shift from 0 to 45 degrees.

16. The IG window unit of claim 1, wherein the IG unit has an outside a* value which does not change by more than 2.5 given a viewing angle shift from 0 to 45 degrees.

17. The IG window unit of claim 1, wherein outside reflective a* and b* of the IG window unit do not change by more than 3.5 given a viewing angle shift from 0 to 45 degrees.

18. The IG window unit of claim 1, wherein the coating comprises at least the following layers from the substrate which supports the coating outwardly:

a first dielectric layer;

a layer comprising zinc oxide;

a first layer comprising silver;

a contact layer comprising an oxide of Ni and/or Cr;

a second dielectric layer;

another layer comprising zinc oxide;

said first contact layer;

said layer comprising silver;

said second contact layer;

a third dielectric layer; and

an overcoat layer.

38. The IG window unit of claim 1, wherein the first and second contact layers each comprise an oxide of the same metal(s).

50. The IG window unit of claim 1, wherein reflective/outside color of the IG window unit does not significantly change as a function of polarization state of incident light.

19. An insulating glass (IG) window unit comprising:

first and second glass substrates, and a coating supported by one of the substrates, the coating comprising;

first and second infrared (IR) reflecting layers, each of the IR reflecting layers being sandwiched between and contacting a pair of contact layers,

wherein the IG window unit has a selectivity (T_vis/SF) of at least 1.75, and a solar factor (SF) of no greater than 27.5.

20. The IG window unit of claim 19, wherein at least one of the contact layers comprises an oxide of Ni and/or Cr.

21. The IG window unit of claim 19, wherein each of the IR reflecting layers comprise silver.

22. The IG window unit of claim 19, wherein the coating includes only two infrared (IR) reflecting layers.

23. The IG window unit of claim 19, wherein the contact layer under at least one of the layers comprising silver is oxided to a lesser extent than is the contact layer located over and contacting that layer comprising silver.

24. The IG window unit of claim 19, wherein the second IR reflecting layer is located above the first IR reflecting layer, and wherein the contact layer under the first IR reflecting layer comprises zinc oxide and the contact layer under the second IR reflecting layer comprises an oxide of Ni and/or Cr.

25. The IG window unit of claim 19, wherein the IG window unit has a selectivity of at least 1.80.

26. The IG window unit of claim 19, wherein the IG window unit has a selectivity of at least 1.85.

27. The IG window unit of claim 19, wherein the IG window unit has a SF of no greater than 27.0.

28. The IG window unit of claim 19, wherein the IG window unit has a visible transmission of from 40 to 60%.

29. The IG window unit of claim 19, wherein the IG window unit has an outside reflective a* value, at a normal viewing angle, of from −

3 to +2.

30. The IG window unit of claim 19, wherein the IG window unit has an outside reflective a* value, at a normal viewing angle, of from −

2.5 to +1.

31. The IG window unit of claim 19, wherein the coating has a sheet resistance (R_s) of no greater than 3.0 ohms/square.

32. The IG window unit of claim 19, wherein the glass substrate supporting the coating is not heat treated with the coating thereon.

33. The IG window unit of claim 19, wherein the IG unit has an outside a* value which does not change by more than 3.5 given a viewing angle shift from 0 to 45 degrees.

34. The IG window unit of claim 19, wherein the IG unit has an outside a* value which does not change by more than 2.5 given a viewing angle shift from 0 to 45 degrees.

35. The IG window unit of claim 19, wherein outside reflective a* and b* of the IG window unit do not change by more than 3.5 given a viewing angle shift from 0 to 45 degrees.

39. The IG window unit of claim 19, wherein the contact layer under at least one of the layers comprising silver is oxided to a lesser extent than is the contact layer located over and contacting that layer comprising silver, and wherein each of the contact layers contacting that layer comprising silver comprise an oxide of the same metal(s).

51. The IG window unit of claim 19, wherein reflective/outside color of the IG window unit does not significantly change as a function of polarization state of incident light.

36. An insulating glass (IG) window unit comprising:

first and second glass substrates, and a coating supported by one of the substrates, the coating comprising first and second infrared (IR) reflecting layers; and

wherein the IG window unit has a selectivity (T_vis/SF) of at least 1.75, and a solar factor (SF) of no greater than 27.5.

37. The IG window unit of claim 36, wherein each of the IR reflecting layers comprise silver, and wherein the IG window unit has a visible transmission of from 40 to 60%.

52. The IG window unit of claim 36, wherein reflective/outside color of the IG window unit does not significantly change as a function of polarization state of incident light.

40. A coated article including a coating supported by a glass substrate, the coating comprising:

at least one layer comprising silver sandwiched between and contacting first and second contact layers, wherein the first contact layer is located below said layer comprising silver and is oxided to a lesser extent than is the second contact layer located above said layer comprising silver; and

wherein the coated article has a selectivity (T_vis/SF) of at least 1.75.

41. The coated article of claim 40, wherein the article has a selectivity of at least 1.80.

42. The coated article of claim 40, wherein the article has a selectivity of at least 1.85.

53. The coated article of claim 40, wherein reflective/outside color of the coated article does not significantly change as a function of polarization state of incident light.

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

a) providing a glass substrate;

b) forming a first contact layer comprising an oxide of at least one metal on the glass substrate;

c) forming a layer comprising silver on and in contact with the first contact layer;

d) forming a second contact layer comprising an oxide of at least one metal on and in contact with the layer comprising silver; and

e) wherein steps b) and d) are performed so that the first contact layer is deposited in a manner so as to be less oxided than the second contact layer as deposited and so that the resulting coated article has a selectivity of at least 1.75.

44. The method of claim 43, wherein each of said forming steps comprises sputtering at least one target.

45. The method of claim 43, wherein steps b) and d) are performed so that the resulting coated article has a selectivity of at least 1.80.

46. The method of claim 43, wherein steps b) and d) are performed so that the resulting coated article has a selectivity of at least 1.85.

47. The method of claim 43, wherein steps b) and d) are performed so that the resulting coated article has a SF of no greater than 27.5.

48. The method of claim 43, wherein steps b) and d) are performed so that the resulting coated article has a SF of no greater than 27.0.

49. The method of claim 43, wherein the coated article comprises only two IR reflecting layers.