STRENGTHENED GLASS WITH DEEP DEPTH OF COMPRESSION

• US 20150259244A1
• Filed: 05/28/2015
• Published: 09/17/2015
• Est. Priority Date: 02/24/2014
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Amin, Jaymin, Egboiyi, Benedict Osobomen, Oram, Pascale, Pesansky, Jonathan David, Reiman, Kevin Barry, Roussev, Rostislav Vatchev, Schneider, Vitor Marino, Strines, Brian Paul
• Granted Patent: US 9,567,254 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 21/002 to perform ion-exchange between alkali ions C03C21/005 takes precedence
• CPC Class Codes: C03C 2204/00 Glasses, glazes or enamels with special properties
• CPC Class Codes: C03C 3/04 containing silica
• CPC Class Codes: C03C 3/085 containing an oxide of a divalent metal
• CPC Class Codes: C03C 3/087 containing calcium oxide, e.g. common sheet or container glass
• CPC Class Codes: C03C 3/091 containing aluminium
• CPC Class Codes: C03C 3/093 containing zinc or zirconium
• CPC Class Codes: C03C 3/095 containing rare earths
• CPC Class Codes: C03C 3/097 containing phosphorus, niobium or tantalum
• CPC Class Codes: C03C 4/18 for ion-sensitive glass
• CPC Class Codes: G06F 1/1637 Details related to the display arrangement, including those related to the mounting of the display in the housing
• CPC Class Codes: G06F 2200/1634 Integrated protective display lid, e.g. for touch-sensitive display in handheld computer
• CPC Class Codes: H04B 1/3827 Portable transceivers
• CPC Class Codes: Y10T 428/315 Surface modified glass [e.g., tempered, strengthened, etc.]

Abstract

Chemically strengthened glass articles having at least one deep compressive layer extending from a surface of the article to a depth of layer DOL of about 130 μm up to about 175 μm or, alternatively, to a depth of compression (DOC) in a range from about 90 μm to about 120 μm within the article. The compressive layer has a stress profile that includes a first substantially linear portion extending from a relatively shallow depth to the DOL or DOC and a second portion extending from the surface to the shallow depth. The second portion is substantially linear at a depth from 0 μm to 5 μm and has a steeper slope than that of the first portion of the profile. Methods of achieving such stress profiles are also described.

Claims

1. A glass article, the glass article having a compressive region extending from a surface of the glass article to a depth of layer DOL in a range from about 130 μ

m to about 175 μ

m, the compressive region having a compressive stress profile, the compressive stress profile comprising;

a. a first portion extending from at least a first depth D1 to the depth of layer DOL, wherein a compressive stress CS1 at a depth d in the first portion is given by the expression 200 MPa−

d·

1.54 MPa/μ

m≦

CS1≦

260 MPa−

d·

1.49 MPa/μ

m, where d is expressed in microns (μ

m) and d>

D1; and

b. a second portion extending from the surface to the first depth D1, where 10 μ

m≦

D1≦

13 μ

m, the second portion having a maximum compressive stress CS2 at the surface in a range from about 700 MPa to about 925 MPa and being substantially linear and having a slope m₂ from the surface to a depth of about 5 μ

m, wherein −

74.00 MPa/μ

m≦

m₂≦

−

70.00 MPa/μ

m.

2. The glass article of claim 1, wherein 185 MPa≦

CS1≦

240 MPa at D1.

3. The glass article of claim 1, wherein the glass article has a thickness t in a range from about 0.75 mm up to about 0.85 mm.

4. The article of claim 3, wherein the glass article exhibits a break load of at least 27 kgf when subjected to abraded ring-on-ring testing.

5. The glass article of claim 1, wherein the glass article comprises an alkali aluminosilicate glass, the alkali aluminosilicate glass comprising at least about 4 mol % P₂O₅ and from 0 mol % to about 5 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.

6. The glass article of claim 4, wherein the alkali aluminosilicate glass comprises up to about 10 mol % Li_zO.

7. The glass article of claim 4, wherein the glass is lithium-free.

8. The glass article of claim 4, wherein the glass comprises from about 40 mol % to about 70 mol % SiO₂;

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

from 0 mol % to about 5 mol % B₂O₃;

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

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

from 0 mol % to about 1 mol % K₂O.

9. The glass article of claim 8, wherein 11 mol %≦

M₂O₃≦

30 mol %.

10. The glass article of claim 8, wherein R_xO is the sum of alkali metal oxides, alkaline earth metal oxides, and transition metal monoxides present in the glass, and wherein 13 mol %≦

R_xO≦

30 mol %.

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

12. The glass article of claim 1, wherein the first portion is linear at a depth d and wherein the compressive stress CS1, extrapolated from the depth d to zero depth below the surface, is in a range from about 200 MPa to about 260 MPa at zero depth.

13. The glass article of claim 1, wherein the glass article has at least a 50% survival rate when dropped in an inverted ball drop test from a height of about 80 cm onto a drop surface.

14. The glass article of claim 1, wherein the glass article forms at least a portion of a cover glass for a consumer electronic device, the consumer electronic device comprising a housing;

electrical components provided at least partially internal to the housing, the electrical components including at least a controller, a memory, and a display, the display being provided at or adjacent to a front surface of the housing;

wherein the cover glass is provided at or over the front surface of the housing and over the display.

27. The glass article of claim 25, wherein The glass article of claim 1, wherein the glass article has a thickness t in a range from about 0.75 mm up to about 0.85 mm.

15. An alkali aluminosilicate glass, the alkali aluminosilicate glass comprising at least about 4 mol % P₂O₅ and from 0 mol % to about 5 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, the alkali aluminosilicate glass having a compressive region extending from a surface of the glass article to a depth of layer DOL in a range from 130 μ

m to 175 μ

m, the compressive region having a maximum compressive stress CS2 in a range from about 700 MPa to about 925 MPa at the surface and a compressive stress profile, the compressive stress profile comprising;

a. a first portion extending from at least a first depth D1 to the depth of layer DOL, wherein a compressive stress CS1 at a depth d in the first portion is given by the expression 200 MPa−

d·

1.54 MPa/μ

m≦

CS1≦

260 MPa−

d·

1.49 MPa/μ

m, where d is expressed in microns (μ

m) and d>

D1; and

b. a second portion extending from the surface to the first depth D1, where 10 μ

m≦

D1≦

13 μ

m, the second portion being substantially linear and having a slope m₂ from the surface to a depth of about 5 μ

m, wherein −

74.00 MPa/μ

m≦

m₂≦

−

70 MPa/μ

m.

16. The alkali aluminosilicate glass of claim 15, wherein the alkali aluminosilicate glass has a thickness t in a range from about 0.75 mm up to about 0.85 mm.

17. The alkali aluminosilicate glass of claim 15, wherein 185 MPa≦

CS₂≦

240 MPa at D1.

18. The alkali aluminosilicate glass of claim 15, wherein the glass is lithium-free.

19. The alkali aluminosilicate glass of claim 15, wherein the glass comprises from about 40 mol % to about 70 mol % SiO₂;

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

from 0 mol % to about 5 mol % B₂O₃;

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

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

from 0 mol % to about 1 mol % K₂O.

20. The alkali aluminosilicate glass of claim 19, wherein 11 mol %≦

M₂O₃≦

30 mol %.

21. The alkali aluminosilicate glass of claim 19, wherein R_xO is the sum of alkali metal oxides, alkaline earth metal oxides, and transition metal monoxides present in the glass, and wherein 13 mol %≦

R_xO≦

30 mol %.

22. The alkali aluminosilicate glass of claim 19, wherein the alkali aluminosilicate glass comprises 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.

23. The alkali aluminosilicate glass of claim 15, wherein the first portion is linear at a depth d, and wherein the compressive stress CS1, extrapolated from the depth d to zero depth below the surface, is in a range from about 200 MPa to about 260 MPa at zero depth.

24. The alkali aluminosilicate glass of claim 15, wherein the glass article has at least a 50% survival rate when dropped in an inverted ball drop test from a height of about 80 cm onto a drop surface.

25. A glass article, the glass article having a compressive region extending from a surface of the glass article to a depth of compression DOC in a range from 90 μ

m to 120 μ

m and having a maximum compressive stress CS2 in a range from about 700 MPa to about 925 MPa at the surface and a compressive stress profile, the compressive stress profile comprising;

a. a first portion extending from at least a first depth D1 to the depth of compression DOC and having a slope m₁, where −

2.89 MPa/μ

m≦

m₁≦

−

1.67 MPa/μ

m; and

b. a second portion extending from the surface to the first depth D1, where 10 μ

m≦

D1≦

13 μ

m, the second portion being substantially linear and having a slope m₂ from the surface to a depth of about 5 μ

m, wherein −

55 MPa/μ

m≦

m₂≦

−

105 MPa/μ

m.

26. The glass article of claim 25, wherein −

74.00 MPa/μ

m≦

m₂≦

−

70.00 MPa/μ

m.

28. The glass article of claim 25, wherein the glass article comprises an alkali aluminosilicate glass, the alkali aluminosilicate glass comprising at least about 4 mol % P₂O₅ and from 0 mol % to about 5 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.

29. The glass article of claim 28, wherein the alkali aluminosilicate glass comprises up to about 10 mol % Li₂O.

30. The glass article of claim 28, wherein the glass comprises from about 40 mol % to about 70 mol % SiO₂;

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

from 0 mol % to about 5 mol % B₂O₃;

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

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

from 0 mol % to about 1 mol % K₂O.

31. The glass article of claim 30, wherein 11 mol %≦

M₂O₃≦

30 mol %.

32. The glass article of claim 30, wherein R_xO is the sum of alkali metal oxides, alkaline earth metal oxides, and transition metal monoxides present in the glass, and wherein 13 mol %≦

R_xO≦

30 mol %.

33. The glass article of claim 30, wherein the alkali aluminosilicate glass comprises 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.

34. The glass article of claim 25, wherein the glass is lithium-free.

35. The glass article of claim 25, wherein the first portion is linear at a depth d, and wherein the compressive stress CS1, extrapolated from the depth d to zero depth below the surface, is in a range from about 200 MPa to about 260 MPa at zero depth.

36. The glass article of claim 25, wherein the glass article has at least a 50% survival rate when dropped in an inverted ball drop test from a height of about 80 cm onto a drop surface.

37. A glass article, the glass article having a compressive region extending from a surface of the glass article to a depth of layer DOL in a range from 130 μ

m to 175 μ

m and having a compressive stress profile, the compressive stress profile comprising;

a. a first portion extending from a depth of at least D1 to the depth of layer DOL, wherein the second portion is linear at a depth d in a range from D1 to the depth of layer DOL and has a slope m₁, where −

1.54 MPa/μ

m≦

m₁≦

−

1.49 MPa/μ

m; and

b. a second portion from the surface to a first depth D1, where 10 μ

m≦

D1≦

13 μ

m, the first portion being linear at a depth in a range from 0 μ

m to 5 μ

m and having a maximum compressive stress CS2 at the surface in a range from about 700 MPa to about 925 MPa and having a slope m₂ wherein −

74.00 MPa/μ

m≦

m₂≦

−

70.00 MPa/μ

m.

38. The glass article of claim 37, wherein 185 MPa≦

CS2≦

240 MPa at D1.

39. The glass article of claim 37, wherein the glass article has a thickness t in a range from about 0.75 mm up to about 0.85 mm.

40. The glass article of claim 37, wherein the glass article comprises an alkali aluminosilicate glass, the alkali aluminosilicate glass comprising at least about 4 mol % P₂O₅ and from 0 mol % to about 5 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.

41. The glass article of claim 40, wherein the alkali aluminosilicate glass comprises up to about 10 mol % Li₂O.

42. The glass article of claim 40, wherein the glass is lithium-free.

43. The glass article of claim 40, wherein the glass comprises from about 40 mol % to about 70 mol % SiO₂;

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

from 0 mol % to about 5 mol % B₂O₃;

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

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

from 0 mol % to about 1 mol % K₂O.

44. The glass article of claim 43, wherein 11 mol %≦

M₂O₃≦

30 mol %.

45. The glass article of claim 43, wherein R_xO is the sum of alkali metal oxides, alkaline earth metal oxides, and transition metal monoxides present in the glass, and wherein 13 mol %≦

R_xO≦

30 mol %.

46. The glass article of claim 43, wherein the alkali aluminosilicate glass comprises 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.

47. The glass article of claim 37, wherein the compressive stress CS1 extrapolated from the depth d to zero depth below the surface is in a range from about 200 MPa to about 260 MPa at zero depth.

48. The glass article of claim 37, wherein the glass article has at least 50% survival rate when dropped in an inverted ball drop test from a height of about 80 cm onto a drop surface.