Ion exchangeable glass with high damage resistance

Patent metadata

Field	Value
Publication number	US-9517967-B2
Application number	US-201313903398-A
Country	US
Kind code	B2
Filing date	May 28, 2013
Priority date	May 31, 2012
Publication date	Dec 13, 2016
Grant date	Dec 13, 2016

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, B 2 O 3 , 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 about 30 kilogram force.

First claim

The invention claimed is:

1. A glass comprising:
a. at least about 50 mol % SiO 2 ;
b. at least about 10 mol % R 2 O, wherein R 2 O comprises at least about 10 mol % Na 2 O;
c. from 12 mol % to about 22 mol % Al 2 O 3 , wherein −1.61 mol %≦Al 2 O 3 (mol %)−R 2 O(mol %)≧2 mol %;
d. from greater than 0 mol % up to 5 mol % B 2 O 3 , wherein B 2 O 3 (mol %)−(R 2 O(mol %)−Al 2 O 3 (mol %))≧4.5 mol %; and
e. at least 0.1 mol % of at least one of MgO and ZnO, wherein the glass is ion exchangeable.

2. The glass of claim 1 , wherein the glass comprises: at least about 50 mol % SiO 2 , from 12 mol % to about 22 mol % Al 2 O 3 ; from about 4.5 mol % to 5 mol % B 2 O 3 ; from about 10 mol % to about 20 mol % Na 2 O; from 0 mol % to about 5 mol % K 2 O; at least about 0.1 mol % of at least one of MgO, ZnO, or combinations thereof, wherein 0 mol %≦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 %.

3. The glass of claim 2 , wherein the glass comprises from about 60 to 66 mol % SiO 2 .

4. The glass of claim 1 , wherein the glass comprises greater than 4.5 mol % B 2 O 3 in which boron cations are three-fold coordinated.

5. 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 μm.

6. The glass of claim 5 , wherein the compressive stress is at least about 800 MPa.

7. The glass of claim 5 , wherein the glass has a Vickers crack initiation threshold of at least about 30 kgf.

8. A glass comprising: at least about 50 mol % SiO 2 ; at least about 10 mol % R 2 O, wherein R 2 O comprises at least about 10 mol % Na 2 O; from 12 mol % to about 22 mol % Al 2 O 3 ; greater than about 2.5 mol % to 5 mol % B 2 O 3 ; and at least 0.1 mol % of at least one of MgO and ZnO, wherein B 2 O 3 (mol %)−(R 2 O(mol %)−Al 2 O 3 (mol %))≧4.5 mol %, wherein the glass has a zircon breakdown temperature at which the viscosity of the glass is greater than about 40 kPoise.

9. The glass of claim 8 , wherein the glass comprises: at least about 50 mol % SiO 2 , from 12 mol % to about 22 mol % Al 2 O 3 ; from about 4.5 mol % to 5 mol % B 2 O 3 ; from about 10 mol % to about 20 mol % Na 2 O; from 0 mol % to about 5 mol % K 2 O; at least about 0.1 mol % of at least one of MgO and ZnO, wherein 0 mol %≦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 %.

10. The glass of claim 9 , wherein the glass comprises from about 60 to about 66 mol % SiO 2 .

11. The glass of claim 8 , wherein the glass comprises greater than about 4.5 mol % B 2 O 3 in which boron cations are three-fold coordinated.

12. The glass of claim 9 , 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 μm.

13. The glass of claim 12 , wherein the compressive stress is at least about 800 MPa.

14. The glass of claim 12 , wherein the glass has a Vickers crack initiation threshold of at least about 30 kgf.

15. A glass, wherein the glass is ion exchanged and has a Vickers crack initiation threshold of at least about 30 kgf, the glass comprising:
a. at least about 60 mol % SiO 2 ;
b. at least about 10 mol % R 2 O, wherein R 2 O comprises at least about 10 mol % Na 2 O;
c. from 12 mol % to about 22 mol % Al 2 O 3 , wherein −1.61 mol %≦Al 2 O 3 (mol %)−R 2 O(mol %)≦2 mol %;
d. from greater than 0 mol % up to 5 mol % B 2 O 3 , wherein B 2 O 3 (mol %)−(R 2 O(mol %)−Al 2 O 3 (mol %))≧4.5 mol %; and
e. at least 0.1 mol % of at least one of MgO and ZnO, wherein the glass is ion exchangeable.

16. The glass of claim 15 , wherein the glass comprises: at least about 50 mol % SiO 2 , from 12 mol % to about 22 mol % Al 2 O 3 ; from about 4.5 mol % to 5 mol % B 2 O 3 ; from about 10 mol % to about 20 mol % Na 2 O; from 0 mol % to about 5 mol % K 2 O; at least about 0.1 mol % of at least one of MgO and ZnO, wherein 0 mol %≦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 %.

17. The glass of claim 16 , wherein the glass comprises from about 60 to about 66 mol % SiO 2 .

18. The glass of claim 15 , wherein the glass comprises greater than about 4.5 mol % B 2 O 3 in which boron cations are three-fold coordinated.

19. The glass of claim 15 , wherein the glass 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 μm.

20. The glass of claim 19 , wherein the compressive stress is at least about 800 MPa.

21. The glass of claim 15 , wherein the Vickers crack initiation threshold is in a range from about 30 kgf to about 35 kgf.

Assignees

• Corning Inc

Inventors

• Dejneka Matthew John
• Ellison Adam James
• Mauro John Christopher

Classifications

• C03C21/002

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

• C03C3/091

  containing aluminium · CPC title

• C03C4/18

  for ion-sensitive glass · CPC title

• C03C3/093 Primary

  containing zinc or zirconium · CPC title

• C03C21/00

  Treatment of glass, not in the form of fibres or filaments, by diffusing ions or metals in the surface · CPC title