Ion exchangable glass with deep compressive layer and high damage threshold

Patent metadata

Field	Value
Publication number	US-9346703-B2
Application number	US-201113305271-A
Country	US
Kind code	B2
Filing date	Nov 28, 2011
Priority date	Nov 30, 2010
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

Glasses comprising SiO 2 , Al 2 O 3 , and P 2 O 5 that are capable of chemical strengthened by ion exchange and having high damage resistance. These phosphate-containing glasses have a structure in which silica (SiO 2 ) is replaced by aluminum phosphate (AlPO 4 ) and/or boron phosphate (BPO 4 ).

First claim

The invention claimed is:

1. A glass comprising SiO 2 , 16 to about 28 mol % Al 2 O 3 , P 2 O 5 , and at least one alkali metal oxide (R 2 O), wherein R 2 O is selected from the group consisting of Na 2 O and K 2 O, wherein 0.75≦[(P 2 O 5 (mol %)+R 2 O(mol %))/M 2 O 3 (mol %)]≦1.3, where M 2 O 3 =Al 2 O 3 +B 2 O 3 , and wherein the glass is lithium-free.

2. The glass of claim 1 , wherein the glass is ion exchanged, and wherein the glass has a Vickers crack initiation threshold of at least about 20 kgf.

3. The glass of claim 1 , wherein the glass is ion exchanged to a depth of layer of at least about 40 μm from a surface of the glass.

4. The glass of claim 3 , wherein the glass is ion exchanged to a depth of layer extending at least about 60 μm from a surface of the glass.

5. The glass of claim 1 , wherein the glass is ion exchanged, and wherein the glass fails at a load of greater than about 80 kgf when subjected to abraded ring-on-ring loading.

6. The glass of claim 1 , wherein the glass has an anneal point of at least about 600° C.

7. The glass of claim 1 , wherein the glass comprises: about 40 to about 70 mol % SiO 2 ; 0 to about 28 mol % B 2 O 3 ; 16 to about 28 mol % Al 2 O 3 ; about 1 to about 14 mol % P 2 O 5 ; and about 12 to about 18 mol % R 2 O.

8. The glass of claim 7 , wherein the glass comprises: about 40 to about 64 mol % SiO 2 ; 0 to about 8 mol % B 2 O 3 ; 16 to about 28 mol % Al 2 O 3 ; about 2 to about 12 mol % P 2 O 5 ; and about 12 to about 16 mol % R 2 O.

9. The glass of claim 7 , wherein the glass further comprises at least one alkaline earth oxide.

10. The glass of claim 1 , wherein aluminum is present in the glass in the form of tetrahedral aluminum oxide units and phosphorus is present in the glass in the form of tetrahedral phosphorus oxide units.

11. The glass of claim 10 , wherein the tetrahedral aluminum oxide and tetrahedral phosphorus oxide units replace tetrahedral silica units in the glass.

12. The glass of claim 1 , wherein boron is present in the glass in the form of tetrahedral boron oxide units and phosphorus is present in the form of tetrahedral phosphorus oxide units.

13. The glass of claim 12 , wherein the tetrahedral boron oxide and tetrahedral phosphorus oxide units replace tetrahedral silica units in the glass.

14. The glass of claim 1 , wherein the glass is substantially free of non-bridging oxygen atoms.

15. The glass of claim 1 , wherein [(P 2 O 5 (mol %)+R 2 O(mol %))/M 2 O 3 (mol %)]=1.

16. The glass of claim 1 , wherein M 2 O 3 ═Al 2 O 3 .

17. The glass of claim 1 , wherein the molar volume of the glass is at least about 29 cm 3 /mol.

18. The glass of claim 1 , wherein the glass has a depth of layer extending to at least about 30 μm from a surface of the glass when ion exchanged in an ion exchange bath comprising KNO 3 at 410° C. for 2 hours.

19. A glass comprising SiO 2 , 16 to about 28 mol % Al 2 O 3 , P 2 O 5 , and at least one alkali metal oxide (R 2 O), wherein R 2 O is selected from the group consisting of Na 2 O and K 2 O, wherein 0.75≦[(P 2 O 5 (mol %)+R 2 O(mol %))/M 2 O 3 (mol %)]≦1.3 and M 2 O 3 =Al 2 O 3 +B 2 O 3 , wherein the glass is lithium-free, and wherein the glass, when ion exchanged, has a Vickers crack initiation threshold of at least about 10 kgf.

20. The glass of claim 19 , wherein the glass is ion exchanged to a depth of layer extending at least about 40 μm from a surface of the glass.

21. The glass of claim 20 , wherein the glass is ion exchanged to a depth of layer extending at least about 60 μm from a surface of the glass.

22. The glass of claim 19 , wherein the glass is ion exchanged, and wherein the glass fails at a load of greater than about 80 kgf when subjected to abraded ring-on-ring loading.

23. The glass of claim 19 , wherein the glass has an anneal point of at least about 600° C.

24. The glass of claim 19 , wherein the glass comprises: about 40 to about 70 mol % SiO 2 ; 0 to about 28 mol % B 2 O 3 ; 16 to about 28 mol % Al 2 O 3 ; about 1 to about 14 mol % P 2 O 5 ; and about 12 to about 18 mol % R 2 O.

25. The glass of claim 24 , wherein the glass comprises: about 40 to about 64 mol % SiO 2 ; 0 to about 8 mol % B 2 O 3 ; 16 to about 28 mol % Al 2 O 3 ; about 2 to about 12 mol % P 2 O 5 ; and about 12 to about 16 mol % R 2 O.

26. The glass of claim 24 , further comprising at least one alkaline earth oxide.

27. The glass of claim 19 , wherein aluminum is present in the glass in the form of tetrahedral aluminum oxide units and phosphorous is present in the glass in the form of tetrahedral phosphorous oxide units.

28. The glass of claim 19 , wherein the tetrahedral aluminum oxide and tetrahedral phosphorous oxide units replace tetrahedral silica units in the glass.

29. The glass of claim 19 , wherein boron is present in the glass in the form of tetrahedral boron oxide units and phosphorous is present in the glass in the form of tetrahedral phosphorous oxide units.

30. The glass of claim 29 , wherein the tetrahedral boron oxide and tetrahedral phosphorous oxide units replace tetrahedral silica units in the glass.

31. The glass of claim 19 , wherein the glass is substantially free of non-bridging oxygens.

32. The glass of claim 19 , wherein [(P 2 O 5 (mol %)+R 2 O(mol %))/M 2 O 3 (mol %)]=1.

33. The glass of claim 19 , wherein M 2 O 3 ═Al 2 O 3 .

34. The glass of claim 19 , wherein the glass has a depth of layer extending to at least about 30 μm from a surface of the glass when ion exchanged in an ion exchange bath comprising KNO 3 at 410° C. for 2 hours.

Assignees

• Bookbinder Dana Craig
• Gross Timothy Michael
• Potuzak Marcel
• Corning Inc

Inventors

• Bookbinder Dana Craig
• Gross Timothy Michael
• Potuzak Marcel

Classifications

• C03C21/002 Primary

  to perform ion-exchange between alkali ions (C03C21/005 takes precedence) · CPC title

• C03C3/064

  containing boron · CPC title

• C03C3/097 Primary

  containing phosphorus, niobium or tantalum · CPC title

• C03C3/062 Primary

  with less than 40% silica by weight · CPC title

• Y10T428/264

  Up to 3 mils · CPC title