STRENGTHENED GLASS WITH ULTRA DEEP DEPTH OF COMPRESSION

• US 20160122239A1
• Filed: 10/29/2015
• Published: 05/05/2016
• Est. Priority Date: 10/31/2014
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Amin, Jaymin, Egboiyi, Benedict Osobomen, Pesansky, Jonathan David, Reiman, Kevin Barry, Roussev, Rostislav Vatchev, Strines, Brian Paul
• Granted Patent: US 10,150,698 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C03C 21/002 to perform ion-exchange between alkali ions C03C21/005 takes precedence
• CPC Class Codes: C03C 3/097 containing phosphorus, niobium or tantalum

Abstract

Chemically strengthened glass articles having at least one deep compressive layer extending from a surface of the article to a depth of compression DOC of at least about 125 μm within the glass article. The compressive stress profile includes a single linear segment or portion extending from the surface to the depth of compression DOC. Alternatively, the compressive stress profile may include an additional portion extending from the surface to a relatively shallow depth and the linear portion extending from the shallow depth to the depth of compression.

Claims

1. A glass article, the glass article having a compressive region having a compressive stress CS_s in a range from about 100 MPa to about 400 MPa at a surface of the glass article, wherein the compressive region extends from the surface to a depth of compression DOC and has a compressive stress profile, wherein 0.1·

t≦

DOC≦

0.25·

t, the compressive stress profile having a portion a extending from the surface to a depth d_a and a slope m_a, wherein the depth d_a is equal to the depth of compression DOC and −

0.4 MPa/μ

m≧

m_a≧

−

3.0 MPa/μ

m.

2. The glass article of claim 1, wherein the depth of compression DOC is in a range from about 95 μ

m to about 250 μ

m.

3. The glass article of claim 2, wherein the depth of compression DOC is in a range from about 100 μ

m to about 190 μ

m.

4. The glass article of claim 1, wherein 0.12·

t≦

DOC≦

0.22·

t.

5. The glass article of claim 1, wherein the glass article has a thickness t in a range from about 0.15 mm up to about 2.0 mm.

6. The glass article of claim 1, wherein the slope m_a is in a range from about −

0.7 MPa/μ

m to about −

2.7 MPa/μ

m.

7. The glass article of claim 1, wherein the slope m_a is in a range from about −

1.5 MPa/μ

m to about −

2.7 MPa/μ

m.

8. The glass article of claim 1, wherein the glass article comprises an alkali aluminosilicate glass.

9. The glass article of claim 8, wherein the alkali aluminosilicate glass comprises up to about 10 mol % Li₂O.

10. The glass article of claim 8, wherein the alkali aluminosilicate glass comprises at least about 4 mol % P₂O₅ and from 0 mol % to about 4 mol % B₂O₃, wherein 1.3<

[(P₂O₅+R₂O)/M₂O₃]≦

2.3, where M₂O₃=Al₂O₃+B₂O₃, and R₂O is the sum of monovalent cation oxides present in the alkali aluminosilicate glass.

11. The glass article of claim 8, wherein the glass is lithium-free.

12. An alkali aluminosilicate glass, the alkali aluminosilicate glass comprising at least about 4 mol % P₂O₅ and from 0 mol % to about 4 mol % B₂O₃, wherein 1.3<

[(P₂O₅+R₂O)/M₂O₃]≦

2.3, where M₂O₃=Al₂O₃+B₂O₃, and R₂O is the sum of monovalent cation oxides present in the alkali aluminosilicate glass, wherein;

a. the alkali aluminosilicate glass is ion exchanged and has thickness t and a compressive region, the compressive region having a compressive stress CS_s in a range from about 100 MPa to about 400 MPa at a surface of the alkali aluminosilicate glass;

b. the compressive region extends from the surface to a depth of compression DOC, wherein 0.1·

t≦

DOC≦

0.25·

t; and

c. the compressive region has a compressive stress profile, the compressive stress profile having a portion a extending from the surface to a depth d_a and a and having a slope m_a, wherein the depth d_a is equal to the depth of compression DOC and −

0.4 MPa/μ

m≧

m_a≧

−

3.0 MPa/μ

m.

13. The alkali aluminosilicate glass of claim 12, wherein the glass is lithium-free.

14. The alkali aluminosilicate glass of claim 12, wherein the glass consists essentially of from about 40 mol % to about 70 mol % SiO₂;

from about 11 mol % to about 25 mol % Al₂O₃;

from about 4 mol % to about 15 mol % P₂O₅;

from about 13 mol % to about 25 mol % Na₂O;

from about 13 to about 30 mol % R_xO, wherein R_xO is the sum of the alkali metal oxides, alkaline earth metal oxides, and transition metal monoxides present in the glass;

from about 11 to about 30 mol % M₂O₃, where M₂O₃=Al₂O₃+B₂O₃;

from 0 mol % to about 1 mol % K₂O;

from 0 mol % to about 4 mol % B₂O₃, and 3 mol % or less of one or more of TiO₂, MnO, Nb₂O₅, MoO₃, Ta₂O₅, WO₃, ZrO₂, Y₂O₃, La₂O₃, HfO₂, CdO, SnO₂, Fe₂O₃, CeO₂, As₂O₃, Sb₂O₃, Cl, and Br; and

1.3<

[(P₂O₅+R₂O)/M₂O₃]≦

2.3, where R₂O is the sum of monovalent cation oxides present in the glass.

15. The glass article of claim 12, wherein the depth of compression DOC is in a range from about 95 μ

m to about 250 μ

m.

16. The glass article of claim 15, wherein the depth of compression DOC is in a range from about 100 μ

m to about 190 μ

m.

17. The glass article of claim 12, wherein 0.12·

t≦

DOC≦

0.22·

t.

18. The glass article of claim 12, wherein the thickness t is in a range from about 0.1 mm to about 2.0 mm.

19. The glass article of claim 12, wherein the slope m_a is in a range from about −

0.7 MPa/μ

m to about −

2.7 MPa/μ

m.

20. The glass article of claim 12, wherein the slope m_a is in a range from about −

1.5 MPa/μ

m to about −

2.7 MPa/μ

m.

21. A glass article, the glass article having a thickness t and a compressive region having a compressive stress CS_s in a range from about 400 MPa to about 1200 MPa at a surface of the glass article, wherein the compressive region extends from the surface to a depth of compression DOC, wherein 0.1·

t≦

DOC≦

0.25·

t, and has a compressive stress profile, the compressive stress profile comprising;

a. a first portion b extending from the surface to a depth d_b below the surface and having a slope m_b, wherein −

40 MPa/μ

m≧

m_b≧

−

200 MPa/μ

m; and

b. a second substantially linear portion c extending from about d_c to the depth of compression DOC and having a slope m_c, wherein −

0.4 MPa/μ

m≧

m_c≧

−

3.0 MPa/μ

m.

22. The glass article of claim 21, wherein the depth of compression DOC is in a range from about 95 μ

m to about 250 μ

m.

23. The glass article of claim 22, wherein the depth of compression DOC is in a range from about 100 μ

m to about 190 μ

m.

24. The glass article of claim 21, wherein 0.12·

t≦

DOC≦

0.22·

t.

25. The glass article of claim 21, wherein the thickness t is in a range from about 0.15 mm to about 2.0 mm.

26. The glass article of claim 21, wherein the slope m_c is in a range from about −

0.7 MPa/μ

m to about −

2.7 MPa/μ

m.

27. The glass article of claim 26, wherein the slope m_c is in a range from about −

1.5 MPa/μ

m to about −

2.7 MPa/μ

m.

28. The glass article of claim 21, wherein the glass article comprises an alkali aluminosilicate glass.

29. The glass article of claim 27, wherein the alkali aluminosilicate glass comprises up to about 10 mol % Li₂O.

30. The glass article of claim 28, wherein the alkali aluminosilicate glass comprises at least about 4 mol % P₂O₅ and from 0 mol % to about 4 mol % B₂O₃, wherein 1.3<

[(P₂O₅+R₂O)/M₂O₃]≦

2.3, where M₂O₃=Al₂O₃+B₂O₃, and R₂O is the sum of monovalent cation oxides present in the alkali aluminosilicate glass.

31. The glass article of claim 28, wherein the glass is lithium-free.

32. The glass article of claim 28, wherein the glass consists essentially of from about 40 mol % to about 70 mol % SiO₂;

from about 11 mol % to about 25 mol % Al₂O₃;

from about 4 mol % to about 15 mol % P₂O₅;

from about 13 mol % to about 25 mol % Na₂O;

from about 13 to about 30 mol % R_xO, wherein R_xO is the sum of the alkali metal oxides, alkaline earth metal oxides, and transition metal monoxides present in the glass;

from about 11 to about 30 mol % M₂O₃, where M₂O₃=Al₂O₃+B₂O₃;

from 0 mol % to about 1 mol % K₂O;

from 0 mol % to about 4 mol % B₂O₃, and 3 mol % or less of one or more of TiO₂, MnO, Nb₂O₅, MoO₃, Ta₂O₅, WO₃, ZrO₂, Y₂O₃, La₂O₃, HfO₂, CdO, SnO₂, Fe₂O₃, CeO₂, As₂O₃, Sb₂O₃, Cl, and Br; and

1.3<

[(P₂O₅+R₂O)/M₂O₃]≦

2.3, where R₂O is the sum of monovalent cation oxides present in the glass.