Crack and scratch resistant glass and enclosures made therefrom

• US 8,586,492 B2
• Filed: 08/18/2010
• Issued: 11/19/2013
• Est. Priority Date: 08/21/2009
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Barefoot, Kristen L, Dejneka, Matthew John, Gomez, Sinue, Gross, Timothy Michael, Shashidhar, Nagaraja
• Primary Examiner(s): GROUP, KARL E
• Application Number:
  US12/858,490
• Publication Number:
  US 20110201490A1
• Time in Patent Office: 1,189 Days
• Field of Search: 501/66, 428/410
• US Class Current: 501/66
• CPC Class Codes: C03B 33/0222 Scoring using a focussed radiation beam, e.g. laser
• CPC Class Codes: C03B 33/04 Cutting or splitting in curves, especially for making spectacle lenses
• CPC Class Codes: C03B 33/091 using at least one focussed radiation beam, e.g. laser beam C03B33/0955 takes precedence
• CPC Class Codes: C03C 21/002 to perform ion-exchange between alkali ions C03C21/005 takes precedence
• CPC Class Codes: C03C 3/091 containing aluminium
• CPC Class Codes: C03C 3/097 containing phosphorus, niobium or tantalum
• CPC Class Codes: Y02P 40/57 Improving the yield, e-g- reduction of reject rates
• CPC Class Codes: Y10T 225/12 With preliminary weakening
• CPC Class Codes: Y10T 428/24777 Edge feature
• CPC Class Codes: Y10T 428/315 Surface modified glass [e.g., tempered, strengthened, etc.]

Abstract

A glass and an enclosure, including windows, cover plates, and substrates for mobile electronic devices comprising the glass. The glass has a crack initiation threshold that is sufficient to withstand direct impact, has a retained strength following abrasion that is greater than soda lime and alkali aluminosilicate glasses, and is resistant to damage when scratched. The enclosure includes cover plates, windows, screens, and casings for mobile electronic devices and information terminal devices.

Claims

1. An aluminoborosilicate glass, the aluminoborosilicate glass comprising at least 50 mol % SiO₂, less than 10 mol % B₂O₃, and at least 8 mol % Na₂O, wherein the aluminoborosilicate glass is free of lithium and ion exchangeable, wherein a ratio

2. The aluminoborosilicate glass of claim 1, wherein the aluminoborosilicate glass has a Vickers median/radial crack initiation threshold of at least 500 gf.

3. The aluminoborosilicate glass of claim 1, wherein the aluminoborosilicate glass exhibits indentation deformation by densification deformation when submitted to an indentation load of at least 500 gf and is free of subsurface shear faulting.

4. The aluminoborosilicate glass of claim 1, wherein the aluminoborosilicate glass has a molar volume of at least 27 cm³/mol.

5. The aluminoborosilicate glass of claim 1, wherein the aluminoborosilicate glass is down-drawable.

6. The aluminoboro silicate glass of claim 1, wherein the at least one modifier includes at least one alkali metal oxide other than Na₂O.

7. The aluminoborosilicate glass of claim 1, wherein 0.9<

(Na₂O(mol %)+R₂O(mol %))/Al₂O₃(mol %)<

1.3.

8. The aluminoborosilicate glass of claim 7, wherein B₂O₃(mol %)>

Na₂O(mol %)+R₂O(mol %)−

Al₂O₃(mol %)).

9. The aluminoborosilicate glass of claim 7, wherein B₂O₃(mol %)>

2(Na₂O(mol %)+R₂O(mol %)−

Al₂O₃(mol %)).

17. The aluminoborosilicate glass of claim 1, wherein the aluminoborosilicate glass is a strengthened aluminoborosilicate glass.

18. The aluminoborosilicate glass of claim 17, wherein the strengthened aluminoborosilicate glass is an ion exchanged aluminoborosilicate glass.

19. The aluminoborosilicate glass of claim 18, wherein the ion exchanged aluminoborosilicate glass has a Vickers median/radial crack initiation threshold of at least 10 kgf.

20. The aluminoborosilicate glass of claim 19, wherein the ion exchanged aluminoborosilicate glass has a Vickers median/radial crack initiation threshold of at least 20 kgf.

21. The aluminoborosilicate glass of claim 20, wherein the ion exchanged aluminoborosilicate glass has a Vickers median/radial crack initiation threshold of at least 30 kgf.

22. The aluminoborosilicate glass of claim 18, wherein the ion exchanged aluminoborosilicate glass exhibits indentation deformation by densification deformation when submitted to an indentation load of at least 500 gf and is free of subsurface shear faulting.

23. The aluminoborosilicate glass of claim 18, wherein the ion exchanged aluminoborosilicate glass has a compressive stress of at least about 400 MPa and a depth of layer of at least about 15 μ

m.

24. The aluminoborosilicate glass of claim 18, wherein the ion exchanged aluminoborosilicate glass is substantially non-frangible.

25. The aluminoborosilicate glass of claim 18, wherein the ion exchanged aluminoborosilicate glass is free of lateral damage extending more than twice a width w of a scratch formed by a Knoop diamond at a load of at least 5 N.

26. The aluminoborosilicate glass of claim 1, wherein

27. The aluminoborosilicate glass of claim 1, wherein the aluminoborosilicate glass is free of at least one of arsenic, antimony, and barium.

28. The aluminoborosilicate glass of claim 1, wherein the aluminoborosilicate glass has a liquidus viscosity of at least 130 kilopoise.

29. The aluminoborosilicate glass of claim 1, wherein the aluminoborosilicate glass is free of non-bridging oxygens.

30. The aluminoborosilicate glass of claim 1, wherein the aluminoborosilicate glass has a thickness in a range from about 0.1 mm up to about 2.0 mm.

10. An aluminoborosilicate glass, the aluminoborosilicate glass comprising:

50-72 mol % SiO₂;

9-17 mol % Al₂O₃;

less than 10 mol % B₂O₃;

8-16 mol % Na₂O; and

0-4 mol % K₂O, wherein the ratio

11. The aluminoborosilicate glass of claim 10, wherein the aluminoborosilicate glass is ion exchanged and has a Vickers median/radial crack initiation threshold of at least 10 kgf.

12. The aluminoborosilicate glass of claim 10, wherein the aluminoborosilicate glass exhibits indentation deformation by densification deformation when submitted to an indentation load of at least 500 gf and is free of subsurface shear faulting.

13. The aluminoborosilicate glass of claim 10, wherein the aluminoborosilicate glass has a Vickers median/radial crack initiation threshold of at least 500 gf.

14. The aluminoborosilicate glass of claim 10, wherein the aluminoborosilicate glass has a molar volume of at least 27 cm³/mol.

15. The aluminoborosilicate glass of claim 10, wherein the aluminoborosilicate glass is ion exchanged and is free of chips having a size greater than two times a width w of a scratch formed by a Knoop diamond at a load of at least 5 N.

31. The aluminoborosilicate glass of claim 11, wherein the Vickers median/radial crack initiation threshold is at least 20 kgf.

32. The aluminoborosilicate glass of claim 11, wherein the Vickers median/radial crack initiation threshold is at least 30 kgf.

33. The aluminoborosilicate glass of claim 10, wherein the aluminoborosilicate glass is ion exchanged.

34. The aluminoborosilicate glass of claim 33, wherein the ion exchanged aluminoborosilicate glass has a compressive stress of about 400 MPa and a depth of layer of at least 15 μ

m.

35. The aluminoborosilicate glass of claim 33, wherein the ion exchanged aluminoborosilicate glass is substantially non-frangible.

36. The aluminoborosilicate glass of claim 10, wherein 0.9 mol %<

(Na₂O(mol %)+R₂O(mol %))/Al₂O₃(mol %) <

1.3 mol %.

37. The aluminoborosilicate glass of claim 36, wherein B₂O₃(mol %)>

Na₂O(mol %)+R₂O(mol %)−

Al₂O₃(mol %).

38. The aluminoborosilicate glass of claim 36, wherein B₂O₃(mol %)>

2(Na₂O(mol %)+R₂O(mol %)−

Al₂O₃(mol %)).

16. An aluminoborosilicate glass, the aluminoborosilicate glass comprising at least 58 mol % SiO₂, less than 10 mol % B₂O₃, and at least 8 mol % Na₂O, wherein the aluminoborosilicate glass is free of lithium and ion exchangeable, wherein a ratio