Zircon compatible, ion exchangeable glass with high damage resistance

• US 8,951,927 B2
• Filed: 05/28/2013
• Issued: 02/10/2015
• Est. Priority Date: 05/31/2012
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Dejneka, Matthew John, Ellison, Adam James, Mauro, John Christopher
• Primary Examiner(s): Group, Karl
• Assistant Examiner(s): Bolden, Elizabeth A
• Application Number:
  US13/903,433
• Publication Number:
  US 20140227523A1
• Time in Patent Office: 623 Days
• Field of Search: 501/66, 428/410, 428/426
• US Class Current: 501/66
• CPC Class Codes: C03C 21/002 to perform ion-exchange between alkali ions C03C21/005 takes precedence
• CPC Class Codes: C03C 2204/00 Glasses, glazes or enamels with special properties
• CPC Class Codes: C03C 3/083 containing aluminium oxide or an iron compound
• CPC Class Codes: C03C 3/085 containing an oxide of a divalent metal
• CPC Class Codes: C03C 3/087 containing calcium oxide, e.g. common sheet or container glass
• CPC Class Codes: C03C 3/091 containing aluminium
• CPC Class Codes: C03C 3/093 containing zinc or zirconium
• CPC Class Codes: C03C 4/18 for ion-sensitive glass
• CPC Class Codes: Y10T 428/315 Surface modified glass [e.g., tempered, strengthened, etc.]

Abstract

An ion exchangeable glass having a high degree of resistance to damage caused by abrasion, scratching, indentation, and the like. The glass comprises alumina, B₂O₃, and alkali metal oxides, and contains boron cations having three-fold coordination. The glass, when ion exchanged, has a Vickers crack initiation threshold of at least 10 kilogram force (kgf).

Claims

1. A glass, the glass comprising:

66-74 mol % SiO₂;

at least about 10 mol % R₂O, wherein R₂O comprises 9-20 mol % Na₂O;

9-22 mol % Al₂O₃, wherein Al₂O₃(mol %)<

R₂O(mol %); and

B₂O₃, wherein B₂O₃(mol %)−

(R₂O(mol %)−

Al₂O₃(mol %))≧

3 mol %, and wherein the glass is ion exchangeable.

2. The glass of claim 1, wherein the glass comprises at least 0.1 mol % of at least one of MgO and ZnO.

3. The glass of claim 1, wherein the glass has a zircon breakdown temperature that is equal to a temperature at which the glass has a viscosity in a range from about 30 kPoise to about 40 kPoise.

4. The glass of claim 1, wherein the glass comprises at least about 2.7 mol % B₂O₃.

5. The glass of claim 4, wherein the glass comprises from about 2.7 mol % to about 4.5 mol % B₂O₃.

6. The glass of claim 1, wherein at least 50% of the B₂O₃ present in the glass comprises three-fold coordinated boron cations.

7. The glass of claim 1, wherein B₂O₃(mol %)−

(R₂O(mol %)−

Al₂O₃(mol %))≦

4.5 mol %.

8. The glass of claim 1, wherein the glass comprises:

from about 3 mol % to about 10 mol % B₂O₃;

from 0 mol % to about 5 mol % K₂O;

at least, 0.1 mol % MgO+ZnO, wherein 0≦

MgO≦

6 and 0≦

ZnO≦

6 mol %; and

, optionally, at least one of CaO, BaO, and SrO, wherein 0 mol %≦

CaO+SrO+BaO≦

2 mol %.

9. The glass of claim 1, wherein the glass is ion exchanged and has a layer under a compressive stress of at least about 600 MPa, the layer extending from a surface of the glass into the glass to a depth of layer of at least about 30 μ

m.

10. The glass of claim 9, wherein the compressive stress is at least about 800 MPa.

11. The glass of claim 9, wherein the glass has a Vickers crack initiation of at least about 10 kgf.

12. The glass of claim 11, wherein the glass has a Vickers crack initiation threshold in a range from about 20 kgf to about 30 kgf.

13. The glass of claim 11, wherein the glass has a Vickers crack initiation threshold in a range from about 30 kgf to about 35 kgf.

14. The glass of claim 1, wherein the glass contains less than about 0.1 inclusion per pound of the glass, the inclusion having a size of at least about 50 μ

m.

15. The glass of claim 1, wherein the glass is down-drawn.

16. The glass of claim 1, wherein the glass has an anneal point and a strain point, and wherein the glass is fast-cooled from a temperature that is above the anneal point or the strain point.

17. A glass, the glass comprising:

at least about 50 mol % SiO₂;

at least about 10 mol % R₂O, wherein R₂O comprises 9-20 mol % Na₂O and 0-0.5 mol % Li₂O;

Al₂O₃; and

2.7-4.5 mol % B₂O₃, wherein B₂O₃−

(R₂O−

Al₂O₃)≧

3 mol %, and

wherein the glass has a zircon breakdown temperature that is equal to the temperature at which the glass has a viscosity in a range from about 25 kPoise to about 40 kPoise.

18. The glass of claim 17, wherein the glass comprises at least about 0.1 mol % of at least one of MgO and ZnO.

19. The glass of claim 17, wherein the glass comprises three-fold coordinated boron cations.

20. The glass of claim 17, wherein at least 50% of the B₂O₃ present in the glass comprises three-fold coordinated boron cations.

21. The glass of claim 17, wherein B₂O₃(mol %)−

(R₂O(mol %)−

Al₂O₃(mol %))≦

4.5 mol %.

22. The glass of claim 17, wherein the glass comprises:

at least about 50 mol % SiO₂, from about 9 mol % to about 22 mol % Al₂O₃;

3 mol % to 4.5 mol % B₂O₃;

from 0 mol % to about 5 mol % K₂O;

at least 0.1 mol % MgO+ZnO, wherein 0≦

MgO≦

6 and 0≦

ZnO≦

6; and

, optionally, at least one of CaO, BaO, and SrO, wherein 0 mol %≦

CaO+SrO+BaO≦

2 mol %.

23. The glass of claim 17, wherein the glass forms at least a portion of a cover plate, a touch screen, a watch crystal, a solar concentrator, a window, a screen, or a container.

24. The glass of claim 17, wherein the glass is ion exchanged and has a layer under a compressive stress of at least about 600 MPa, the layer extending from a surface of the glass into the glass to a depth of layer of at least about 30 μ

m.

25. The glass of claim 24, wherein the compressive stress is at least about 800 MPa.

26. The glass of claim 24, wherein the glass has a Vickers crack initiation threshold of at least about 10 kgf.

27. The glass of claim 26, wherein the glass has a Vickers crack initiation threshold in a range from about 20 kgf to about 30 kgf.

28. The glass of claim 26, wherein the glass has a Vickers crack initiation threshold in a range from about 30 kgf to about 35 kgf.

29. The glass of claim 17, wherein the glass contains less than about 0.1 inclusion per pound of the glass, the inclusion having a size of at least about 50 μ

m.

30. The glass of claim 17, wherein the glass is down-drawn.

31. The glass of claim 17, wherein the glass has an anneal point and a strain point, and wherein the glass is fast-cooled from a temperature that is above the anneal point or the strain point.

32. A glass comprising:

66-74 mol % SiO₂;

at least about 10 mol % R₂O, wherein R₂O comprises 9-20 mol % Na₂O;

Al₂O₃, wherein Al₂O₃(mol %)<

R₂O(mol %); and

at least 2.7 mol % B₂O₃, wherein B₂O₃(mol %)−

(R₂O(mol %)−

Al₂O₃(mol %))≦

3 mol %.

33. The glass of claim 32, wherein the glass comprises at least 0.1 mol % of at least one of MgO and ZnO.

34. The glass of claim 32, wherein the glass comprises from 2.7 mol % to 4.5 mol % B₂O₃.

35. The glass of claim 32, wherein B₂O₃(mol %)−

(R₂O(mol %)−

Al₂O₃(mol %))≦

4.5 mol %.

36. The glass of claim 32, wherein at least 50% of the B₂O₃ present in the glass comprises three-fold coordinated boron cations.

37. The glass of claim 32, wherein the glass comprises:

from about 9 mol % to about 22 mol % Al₂O₃;

from about 3 mol % to about 10 mol % B₂O₃;

from 0 mol % to about 5 mol % K₂O;

at least 0.1 mol % MgO+ZnO, wherein 0≦

MgO≦

6 and 0≦

ZnO≦

6; and

, optionally, at least one of CaO, BaO, and SrO, wherein 0 mol %≦

CaO+SrO+BaO≦

2 mol %.

38. The glass of claim 32, wherein the glass is ion exchanged and has a layer under a compressive stress of at least about 600 MPa, the layer extending from a surface of the glass into the glass to a depth of layer of at least about 30 μ

m.

39. The glass of claim 38, wherein the compressive stress is at least about 800 MPa.

40. The glass of claim 32, wherein the glass is ion exchanged and has a Vickers crack initiation threshold in a range from about 20 kgf to about 30 kgf.

41. The glass of claim 32, wherein the glass is ion exchanged and has a Vickers crack initiation threshold in a range from about 30 kgf to about 35 kgf.

42. The glass of claim 32, wherein the glass contains less than about 0.1 inclusion per pound of the glass, the inclusion having a size of at least about 50 μ

m.

43. The glass of claim 32, wherein the glass is down-drawn.

44. The glass of claim 32, wherein the glass has an anneal point and a strain point, and wherein the glass is fast-cooled from a temperature that is above the anneal point or the strain point.

45. The glass of claim 32, wherein the glass is ion exchanged and forms at least a portion of a cover plate, a touch screen, a watch crystal, a solar concentrator, a window, a screen, or a container.

46. A glass comprising:

66-74 mol % SiO₂;

at least about 10 mol % R₂O, wherein R₂O comprises Na₂O;

9-22 mol % Al₂O₃;

at least 2.7 mol % B₂O₃, wherein B₂O₃−

(R₂O−

Al₂O₃)≧

3 mol %; and

at least 0.1 mol % of at least one of MgO and ZnO.

47. The glass of claim 46, wherein the glass has a zircon breakdown temperature that is equal to a temperature at which the glass has a viscosity in a range from about 30 kPoise to about 40 kPoise.

48. The glass of claim 46, wherein the glass comprises from 2.7 mol % to about 4.5 mol % B₂O₃.

49. The glass of claim 46, wherein at least 50% of the B₂O₃ present in the glass comprises three-fold coordinated boron cations.

50. The glass of claim 46, wherein B₂O₃(mol %)−

(R₂O(mol %)−

Al₂O₃(mol %))≦

4.5 mol %.

51. The glass of claim 46, wherein the glass comprises:

from about 3 mol % to about 10 mol % B₂O₃;

from about 9 mol % to about 20 mol % Na₂O;

from 0 mol % to about 5 mol % K₂O;

at least 0.1 mol % MgO+ZnO, wherein 0≦

MgO≦

6 and 0≦

ZnO≦

6 mol %; and

, optionally, at least one of CaO, BaO, and SrO, wherein 0 mol %≦

CaO+SrO+BaO≦

2 mol %.

52. The glass of claim 46, wherein the glass is ion exchanged and has a layer under a compressive stress of at least about 600 MPa, the layer extending from a surface of the glass into the glass to a depth of layer of at least about 30 μ

m.

53. The glass of claim 52, wherein the compressive stress is at least about 800 MPa.

54. The glass of claim 52, wherein the glass has a Vickers crack initiation threshold of at least about 10 kgf.

55. The glass of claim 54, wherein the glass has a Vickers crack initiation threshold in a range from about 20 kgf to about 30 kgf.

56. The glass of claim 54, wherein the glass has a Vickers crack initiation threshold in a range from about 30 kgf to about 35 kgf.

57. The glass of claim 46, wherein the glass contains less than about 0.1 inclusion per pound of the glass, the inclusion having a size of at least about 50 μ

m.

58. The glass of claim 46, wherein the glass is down-drawn.

59. The glass of claim 46, wherein the glass has an anneal point and a strain point, and wherein the glass is fast-cooled from a temperature that is above the anneal point or the strain point.