ION EXCHANGEABLE ALKALI ALUMINOSILICATE GLASS ARTICLES

• US 20120308827A1
• Filed: 05/31/2011
• Published: 12/06/2012
• Est. Priority Date: 05/31/2011
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Boek, Heather Debra, Weller, Mark Owen, Youngman, Randall Eugene
• Granted Patent: US 8,889,575 B2
• Time in Patent Office: Days
• US Class Current: 428/410
• CPC Class Codes: C03C 21/00 Treatment of glass, not in the form of fibres or filaments, by diffusing ions or metals in the surface
• CPC Class Codes: C03C 21/001 in liquid phase, e.g. molten salts, solutions
• CPC Class Codes: C03C 21/002 to perform ion-exchange between alkali ions C03C21/005 takes precedence
• CPC Class Codes: C03C 3/064 containing boron
• CPC Class Codes: C03C 3/076 with 40% to 90% silica, by weight C03C3/045 takes precedence
• CPC Class Codes: C03C 3/083 containing aluminium oxide or an iron compound
• CPC Class Codes: C03C 3/089 containing boron
• CPC Class Codes: C03C 3/091 containing aluminium
• CPC Class Codes: C03C 3/097 containing phosphorus, niobium or tantalum
• CPC Class Codes: C03C 3/112 containing fluorine
• CPC Class Codes: C03C 3/115 containing boron
• CPC Class Codes: C03C 3/118 containing aluminium
• CPC Class Codes: Y10T 428/315 Surface modified glass [e.g., tempered, strengthened, etc.]

Abstract

Ion exchangeable glass articles are disclosed. In one embodiment, a glass article formed from alkali aluminosilicate glass which may include Ga₂O₃, Al₂O₃, Na₂O, SiO₂, B₂O₃, P₂O₅ and various combinations thereof. The glass article may generally include about X mol % of Ga₂O₃ and about Z mol % of Al₂O₃, wherein 0≦x≦20, 0≦z≦25 and 10≦(X+Z)≦25. The glass article may also include from about 5 mol % to about 35 mol % Na₂O, SiO₂ may be present in an amount from about 40 mol % to about 70 mol % SiO₂. The glass article may further include Y mol % B₂O₃ where Y is from 0 to about 10. The glass article may further include (10-Y) mol % of P₂O₅. Glass articles formed according to the present invention may be ion-exchange strengthened. In addition, the glass articles may have a low liquid CTE which enables the glass articles to be readily formed into complex shapes.

Claims

1. A glass article formed from alkali aluminosilicate glass, the alkali aluminosilicate glass comprising:

about X mol % of Ga₂O₃, wherein 0≦

X≦

20;

about Z mol % of Al₂O₃, wherein 0≦

Z≦

25 and 10≦

(X+Z)≦

25;

from about 5 mol % to about 35 mol % Na₂O;

from about 40 mol % to about 70 mol % SiO₂;

Y mol % of B₂O₃, where Y is from 0 to about 10; and

(10-Y) mol % of P₂O₅.

2. The glass article of claim 1, wherein 17≦

(X+Z)≦

24.

3. The glass article of claim 1, wherein

4. The glass article of claim 1, wherein Y<

6.2.

5. The glass article of claim 1, wherein a softening point of the alkali aluminosilicate glass is less than about 870°

C.

6. The glass article of claim 1, wherein the glass article is ion-exchange strengthened such that the glass article has a compressive stress greater than about 625 MPa and a depth of layer greater than about 30 μ

m.

7. The glass article of claim 6, wherein the depth of layer is greater than about 45 μ

m.

8. The glass article of claim 6, wherein the compressive stress is greater than about 700 MPa.

9. The glass article of claim 1, wherein the alkali aluminosilicate glass has a liquid CTE <

30 ppm/°

C. at temperatures above a glass transition temperature of the alkali aluminosilicate glass.

10. The glass article of claim 1, wherein X=0 and a ratio of a concentration of Na₂O (mol %) to a concentration of Al₂O₃ (mol %) is ≧

1.5.

11. The glass article of claim 10, wherein

12. The glass article of claim 10, wherein the glass article is ion-exchange strengthened such that the glass article has a compressive stress of greater than about 500 MPa and a depth of layer greater than about 10 μ

m.

13. A glass article formed from alkali aluminosilicate glass, the alkali aluminosilicate glass comprising:

about X mol % of Ga₂O₃, wherein 0≦

X≦

20;

about Z mol % of Al₂O₃, wherein 0≦

Z≦

25 and 10≦

(X+Z)≦

25;

from about 5 mol % to about 35 mol % Na₂O;

from about 40 mol % to about 70 mol % SiO₂; and

from about 1 mol % to about 10 mol % B₂O₃, wherein the alkali aluminosilicate glass has a softening point ≦

875°

C.

14. The glass article of claim 13, wherein 1≦

X≦

12.

15. The glass article of claim 13, wherein X≧

4 and Z≧

7.

16. The glass article of claim 13, wherein the glass article comprises ≧

4 mol % B₂O₃.

17. The glass article of claim 13, wherein the alkali aluminosilicate glass comprises from about 50 mol % to about 65 mol % SiO₂.

18. The glass article of claim 13, wherein the alkali aluminosilicate glass comprises from about 15 mol % to about 25 mol % Na₂O.

19. The glass article of claim 13, wherein the softening point of the alkali aluminosilicate glass ≦

850°

C.

20. The glass article of claim 13, wherein

21. A glass article formed from alkali aluminosilicate glass, the alkali aluminosilicate glass comprising:

about X mol % of Ga₂O₃, wherein 0≦

X≦

20;

about Z mol % of Al₂O₃, wherein 0≦

Z≦

25 and 10≦

(X+Z)≦

25;

from about 5 mol % to about 35 mol % Na₂O;

from about 40 mol % to about 70 mol % SiO₂; and

from about 1 mol % to about 10 mol % P₂O₅, wherein the alkali aluminosilicate glass has a softening point ≦

975°

C.

22. The glass article of claim 21, wherein the glass article comprises ≧

4 mol % P₂O₅.

23. The glass article of claim 21, wherein X≧

2 and Z≧

10.

24. The glass article of claim 23, wherein X≦

10 and Z≦

18.

25. The glass article of claim 21, wherein the softening point of the alkali aluminosilicate glass is ≦

900°

C.

26. A glass article comprising alkali aluminosilicate glass, the alkali aluminosilicate glass comprising:

from about 10 mol % to about 20 mol % Al₂O₃;

from about 40 mol % to about 70 mol % SiO₂;

from about 10 mol % to about 20 mol % Na₂O;

Y mol % B₂O₃, where Y is from 0-5;

(5-Y) mol % P₂O₅; and

from about 1 mol % to about 6 mol % fluorine.

27. The glass article of claim 26, wherein the glass article is ion-exchange strengthened such that the glass article has a compressive stress greater than about 1000 MPa and a depth of layer greater than about 40 μ

m.

28. The glass article of claim 26, wherein a softening point of the alkali aluminosilicate glass is less than about 930°

C.