ALKALI-DOPED AND ALKALI-FREE BOROALUMINOSILICATE GLASS

• US 20150051060A1
• Filed: 08/08/2014
• Published: 02/19/2015
• Est. Priority Date: 08/15/2013
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Ellison, Adam James, Mauro, John Christopher, Noni, Douglas Miles Jr., Venkataraman, Natesan, Frackenpohl, Jason Sanger
• Granted Patent: US 9,643,884 B2
• Time in Patent Office: Days
• US Class Current: 501/37
• CPC Class Codes: B32B 17/06 comprising glass as the main or only constituent of a layer, next to another layer of a specific material
• CPC Class Codes: C03B 17/02 Forming molten glass coated with coloured layers; Forming molten glass of different compositions or layers; Forming molten glass comprising reinforcements or inserts
• CPC Class Codes: C03B 17/064 by the overflow downdraw fusion process; Isopipes therefor
• CPC Class Codes: C03C 13/046 Multicomponent glass compositions
• CPC Class Codes: C03C 3/091 containing aluminium
• CPC Class Codes: C03C 3/093 containing zinc or zirconium
• CPC Class Codes: C03C 3/095 containing rare earths
• CPC Class Codes: C03C 3/11 containing halogen or nitrogen
• CPC Class Codes: C03C 3/118 containing aluminium
• CPC Class Codes: H01Q 1/2283 mounted in or on the surface of a semiconductor substrate as a chip-type antenna or integrated with other components into an IC package
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 15/0013 said selective devices working as frequency-selective reflecting surfaces, e.g. FSS, dichroic plates, surfaces being partly transmissive and reflective
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40

Abstract

Alkali-doped boroaluminosilicate glasses are provided. The glasses include the network formers SiO₂, B₂O₃, and Al₂O₃. The glass may, in some embodiments, have a Young'"'"'s modulus of less than about 65 GPa and/or a coefficient of thermal expansion of less than about 40×10⁻⁷/° C. The glass may be used as a cover glass for electronic devices, a color filter substrate, a thin film transistor substrate, or an outer clad layer for a glass laminate.

Claims

1. A glass, the glass comprising:

from about 50 mol % to about 70 mol % SiO₂;

from about 5 mol % to about 20 mol % Al₂O₃;

from about 12 mol % to about 35 mol % B₂O₃;

up to about 5 mol % MgO;

up to about 12 mol % CaO; and

up to about 5 mol % SrO; and

wherein a sum of alkali metal oxide modifiers is less than or equal to about 1 mol %.

2. The glass of claim 1, wherein 4 mol %≦

MgO+CaO+SrO≦

Al₂O₃+1 mol %.

3. The glass of claim 1, wherein the glass has a Young'"'"'s modulus of less than about 65 GPa.

4. The glass of claim 3, wherein the Young'"'"'s modulus is less than about 60 GPa.

5. The glass of claim 1, wherein the glass has a coefficient of thermal expansion of less than about 40×

10<sup>−

7</sup>/°

C.

6. The glass of claim 5, wherein the coefficient of thermal expansion is less than about 35×

10<sup>−

7</sup>/°

C.

7. The glass of claim 1, wherein the glass further comprises at least one fining agent.

8. The glass of claim 7, wherein the at least one fining agent comprises at least one of SnO₂, CeO₂, As₂O₃, Sb₂O₅, Cl⁻

, and F⁻

.

9. The glass of claim 8, wherein the at least one fining agent comprises at least one of up to about 0.7 mol % SnO₂, 0.7 mol % CeO₂, up to about 0.5 mol % As₂O₃, and up to about 0.5 mol % Sb₂O₃.

10. The glass of claim 1, wherein the glass comprises a total amount of MgO, CaO, and SrO that is greater than or equal to about 4 mol %.

11. The glass of claim 10, wherein 4 mol %≦

MgO+CaO+SrO≦

Al₂O₃.

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

from about 55 mol % to about 70 mol % SiO₂;

from greater than 6 mol % to about 10 mol % Al₂O₃;

from about 18 mol % to about 30 mol % B₂O₃;

up to about 3 mol % MgO;

up to about 10 mol % CaO;

up to about 3 mol % SrO;

13. The glass of claim 12, wherein the glass comprises up to about 0.2 mol % SnO₂.

14. The glass of claim 1, wherein the glass forms a clad layer in a glass laminate, the glass laminate comprising a core glass and having a coefficient of thermal expansion that is greater than a coefficient of thermal expansion of the clad layer.

15. The glass of claim 14, wherein the clad layer is under a compressive stress of at least about 40 MPa.

16. The glass of claim 1, wherein the glass has a liquidus viscosity of at least 100 kpoise.

17. The glass of claim 16, wherein the glass is down-drawable.

18. The glass of claim 1, wherein the glass comprises up to about 0.5 mol % Fe₂O₃ and up to about 0.1 mol % ZrO₂.

19. The glass of claim 1, wherein the glass is free of alkali metal oxide modifiers.

20. The glass of claim 1, wherein the glass has a Knoop scratch threshold of at least 15 N.

21. The glass of claim 20, wherein the glass has a Knoop scratch threshold of at least 20 N.

22. The glass of claim 1, wherein the glass forms at least a portion of a color filter substrate, a thin film transistor substrate, a cover glass, or a touch interface.

23. A glass comprising SiO₂, B₂O₃, and Al₂O₃, wherein a sum of alkali metal oxide modifiers is less than or equal to about 1 mol % and the glass is substantially free of P₂O₅, and wherein the glass has at least one of a Young'"'"'s modulus of less than about 65 GPa and a coefficient of thermal expansion of less than about 40×

10<sup>−

7</sup>/°

C.

24. The glass of claim 23, wherein the Young'"'"'s modulus is less than about 60 GPa.

25. The glass of claim 23, wherein the coefficient of thermal expansion is less than about 35×

10<sup>−

7</sup>/°

C.

26. The glass of claim 23, wherein the glass comprises:

from about 50 mol % to about 70 mol % SiO₂;

from about 5 mol % to about 20 mol % Al₂O₃;

from about 12 mol % to about 35 mol % B₂O₃;

up to about 5 mol % MgO;

up to about 12 mol % CaO; and

up to about 5 mol % SrO; and

wherein the sum of alkali metal oxide modifiers is less than or equal to about 1 mol %.

27. The glass of claim 26, wherein the glass further comprises at least one fining agent, the fining agent comprising at least one of SnO₂, CeO₂, As₂O₃, Sb₂O₅, Cl⁻

, and F⁻

.

28. The glass of claim 27, wherein the at least one fining agent comprises at least one of up to about 0.7 mol % SnO₂, up to about 0.5 mol % As₂O₃, and up to about 0.5 mol % Sb₂O₃.

29. The glass of claim 24, wherein the glass comprises a total amount of MgO, CaO, and SrO that is greater than or equal to about 4 mol %.

30. The glass of claim 29, wherein 4 mol %≦

MgO+CaO+SrO≦

Al₂O₃+1 mol %.

31. The glass of claim 23, wherein the glass comprises:

from about 55 mol % to about 70 mol % SiO₂;

from greater than 6 mol % to about 10 mol % Al₂O₃;

from about 18 mol % to about 30 mol % B₂O₃;

up to about 3 mol % MgO;

up to about 10 mol % CaO; and

up to about 3 mol % SrO and, optionally, at least one fining agent.

32. The glass of claim 31, wherein the at least one fining agent comprises up to about 0.2 mol % SnO₂.

33. The glass of claim 31, wherein 4 mol %≦

MgO+CaO+SrO≦

Al₂O₃.

34. The glass of claim 23, wherein the glass forms a clad layer in a glass laminate comprising a core glass, wherein the core glass has a coefficient of thermal expansion that is greater than a coefficient of thermal expansion of the clad layer.

35. The glass of claim 34, wherein the clad layer is under a compressive stress of at least about 40 MPa.

36. The glass of claim 23, wherein the glass forms at least a portion of a color filter substrate, a thin film transistor substrate, a cover glass, or a touch interface.

37. The glass of claim 23, wherein the glass has a liquidus viscosity of at least 100 kpoise.

38. The glass of claim 37, wherein the glass is down-drawable.

39. The glass of claim 23, wherein the glass has a Knoop scratch threshold of at least 15 N.

40. The glass of claim 39, wherein the glass has a Knoop scratch threshold of at least 20 N.

44. The glass laminate of claim 40, wherein the at least one fining agent comprises at least one of SnO₂, CeO₂, As₂O₃, Sb₂O₅, Cl⁻

, and F⁻

.

41. A glass laminate, the glass laminate comprising a core glass and a clad glass laminated onto an outer surface of the core glass, the clad glass layer comprising SiO₂, B₂O₃, and Al₂O₃, wherein a sum of alkali metal oxide modifiers in the clad glass is less than or equal to about 1 mol %, and wherein the clad glass has a first coefficient of thermal expansion of less than about 40×

10<sup>−

7</sup>/°

C. and the core glass has a second coefficient of thermal expansion that is greater than the first coefficient of thermal expansion.

42. The glass laminate of claim 41, wherein the first coefficient of thermal expansion is less than about 35×

10<sup>−

7</sup>/°

C.

43. The glass laminate of claim 41, wherein the clad glass comprises:

from about 50 mol % to about 70 mol % SiO₂;

from about 5 mol % to about 20 mol % Al₂O₃;

from about 12 mol % to about 35 mol % B₂O₃;

up to about 5 mol % MgO;

up to about 12 mol % CaO;

up to about 5 mol % SrO; and

, optionally, at least one fining agent, wherein the sum of alkali metal oxide modifiers is less than or equal to about 1 mol %.

45. The glass laminate of claim 41, wherein the at least one fining agent comprises at least one of up to about 0.7 mol % SnO₂, up to about 0.5 mol % As₂O₃, and up to about 0.5 mol % Sb₂O₃.

46. The glass laminate of claim 41, the clad glass comprises a total amount of MgO, CaO, and SrO that is greater than or equal to about 4 mol %.

47. The glass laminate of claim 41, wherein the clad glass comprises:

from about 55 mol % to about 70 mol % SiO₂;

from greater than 6 mol % to about 10 mol % Al₂O₃;

from about 18 mol % to about 30 mol % B₂O₃;

up to about 3 mol % MgO;

up to about 10 mol % CaO;

up to about 3 mol % SrO; and

, and, optionally, at least one fining agent, wherein the sum of alkali metal oxide modifiers is less than or equal to about 0.5 mol %.

48. The glass laminate of claim 47, wherein the at least one fining agent comprises about 0.2 mol % SnO₂.

49. The glass laminate of claim 41, wherein the clad glass is under a compressive stress of at least about 40 MPa.

50. The glass laminate of claim 41, wherein the core glass comprises an alkali aluminosilicate glass.

51. The glass laminate of claim 41, wherein the clad glass is free of alkali metal oxide modifiers.

52. The glass of claim 41, wherein the glass has a Knoop scratch threshold of at least 15 N.

53. The glass of claim 52, wherein the glass has a Knoop scratch threshold of at least 20 N.

54. The glass laminate of claim 41, wherein the clad glass has a liquidus viscosity of at least about 70 kPoise.

62. The method of claim 51, wherein the Young'"'"'s modulus is less than about 60 GPa.

55. A method of making a glass, the method comprising:

a. providing a glass melt, the glass melt comprising SiO₂, B₂O₃, and Al₂O₃, wherein a sum of alkali metal oxide modifiers in the glass melt is less than or equal to about 1 mol %; and

b. down-drawing the glass melt to form the glass.

56. The method of claim 55, wherein down-drawing the glass melt comprises fusion-drawing the glass melt.

57. The method of claim 55, wherein the glass melt is a clad glass melt, and wherein the method further comprises:

a. providing a core glass melt;

b. fusion-drawing the core glass melt to form a core glass; and

c. fusion-drawing the clad glass melt to form a clad layer glass surrounding the core glass, wherein the core glass has a coefficient of thermal expansion that is greater than that of the clad glass.

58. The method of claim 57, wherein the clad layer is under a compressive stress of at least about 100 MPa.

59. The method of claim 55, wherein the clad layer has a coefficient of thermal expansion of less than about 40×

10<sup>−

7</sup>/°

C.

60. The method of claim 59, wherein the coefficient of thermal expansion is less than about 35×

10<sup>−

7</sup>/°

C.

61. The method of claim 55, wherein the glass has a Young'"'"'s modulus of less than about 65 GPa.

63. The method of claim 55, wherein the clad glass has a liquidus viscosity of at least about 70 kPoise.

64. The method of claim 55, wherein the clad glass comprises:

wherein the glass comprises;

from about 50 mol % to about 70 mol % SiO₂;

from about 5 mol % to about 20 mol % Al₂O₃;

from about 12 mol % to about 35 mol % B₂O₃;

up to about 5 mol % MgO;

up to about 12 mol % CaO;

up to about 5 mol % SrO; and

, optionally, at least one fining agent, wherein the sum of alkali metal oxide modifiers is less than or equal to about 1 mol %.

65. The method of claim 64, wherein the clad glass comprises:

from about 55 mol % to about 70 mol % SiO₂;

from greater than 6 mol % to about 10 mol % Al₂O₃;

from about 18 mol % to about 30 mol % B₂O₃;

up to about 3 mol % MgO;

up to about 10 mol % CaO;

up to about 3 mol % SrO; and

, and, optionally, at least one fining agent, wherein the sum of alkali metal oxide modifiers is less than or equal to about 0.5 mol %.

66. The method of claim 64, wherein the clad glass comprises a total amount of MgO, CaO, and SrO that is greater than or equal to about 4 mol %.

67. The method of claim 55, wherein the glass is free of alkali metal oxide modifiers.