Glass article and display device including the same

Patent metadata

Field	Value
Publication number	US-11420903-B2
Application number	US-202017093041-A
Country	US
Kind code	B2
Filing date	Nov 9, 2020
Priority date	Apr 13, 2020
Publication date	Aug 23, 2022
Grant date	Aug 23, 2022

Abstract

A glass article includes a first surface, a second surface opposed to the first surface, a first compressive region extending from the first surface to a first compression depth, a second compressive region extending from the second surface to a second compression depth and a tensile region between the first compression depth and the second compression depth. A stress profile of the first compressive region includes a first segment located between the first surface and a first transition point and a second segment located between the first transition point and the first compression depth. A depth from the first surface to the first transition point ranges from 6.1 μm to 8.1 μm. A compressive stress at the first transition point ranges from 207 MPa to 254 MPa. A stress-depth ratio of the first transition point ranges from 28 MPa/μm to 35 MPa/μm.

First claim

What is claimed is:

1. A glass article comprising:
a first surface;
a second surface opposed to the first surface;
a first compressive region extending from the first surface to a first compression depth;
a second compressive region extending from the second surface to a second compression depth; and
a tensile region between the first compression depth and the second compression depth,
wherein a stress profile of the first compressive region includes a first segment located between the first surface and a first transition point and a second segment located between the first transition point and the first compression depth,
wherein a depth from the first surface to the first transition point ranges from 6.1 μm to 8.1 μm,
wherein a compressive stress at the first transition point ranges from 207 MPa to 254 MPa and is 0.218 to 0.363 times a compressive stress at the first surface,
wherein a stress-depth ratio at the first transition point ranges from 28 MPa/μm to 35 MPa/μm, and
wherein a compressive energy of the first compressive region ranges from 12,800 J/mm 2 to 15,645 J/mm 2 .

2. The glass article of claim 1 , wherein a first compressive energy of the first segment is smaller than a second compressive energy of the second segment.

3. The glass article of claim 2 , wherein the second compressive energy has a magnitude of 2 to 5 times the first compressive energy.

4. The glass article of claim 3 , wherein the first compressive energy ranges from 2,866 J/mm 2 to 3,504 J/mm 2 , and the second compressive energy ranges from 9,334 J/mm 2 to 12,141 J/mm 2 .

5. The glass article of claim 1 , wherein the compressive stress at the first surface ranges from 700 MPa to 950 MPa.

6. The glass article of claim 1 , wherein the first compression depth ranges from 125 μm to 135 μm.

7. The glass article of claim 6 , wherein the depth of the first transition point is 0.045 to 0.065 times the first compression depth.

8. The glass article of claim 1 , wherein the first segment has a first slope,
wherein the second segment has a second slope,
wherein a tangent line of the stress profile at the first transition point has a third slope, and
wherein an absolute value of the third slope is smaller than an absolute value of the first slope and greater than an absolute value of the second slope.

9. The glass article of claim 8 , wherein the absolute value of the third slope is in a range of 19 MPa/μm to 22 MPa/μm.

10. The glass article of claim 9 , wherein a y-intercept of the tangent line of the stress profile at the first transition point is in a range of 350 MPa to 420 MPa.

11. The glass article of claim 1 , wherein the glass article contains lithium aluminosilicate.

12. The glass article of claim 1 , wherein the first compression depth is a maximum penetration depth of sodium ions, and
wherein the depth of the first transition point is a maximum penetration depth of potassium ions.

13. The glass article of claim 1 , wherein a stress profile of the second compressive region includes a third segment located between the second surface and a second transition point and a fourth segment located between the second transition point and the second compression depth,
wherein a depth from the second surface to the second transition point ranges from 6.1 μm to 8.1 μm,
wherein a compressive stress at the second transition point ranges from 207 MPa to 254 MPa, and
wherein a stress-depth ratio at the second transition point ranges from 28 MPa/μm to 35 MPa/μm.

14. The glass article of claim 13 , wherein the stress profile of the second compressive region has a symmetrical relationship with the stress profile of the first compressive region.

15. The glass article of claim 1 , wherein a maximum tensile stress of the tensile region is in a range of 75 MPa to 85 MPa.

16. The glass article of claim 1 , wherein a median of a limited drop height is greater than or equal to 80 cm in a ball-on-ring (BOR) test of the glass article utilizing a ball of 60 g for 10 or more samples.

17. The display device of claim 1 , wherein the compressive stress at the first transition point is 0.267 to 0.296 times the compressive stress at the first surface.

Assignees

• Samsung Display Co Ltd

Inventors

• Shim Gyu In
• Kim Seung
• Kang Byung Hoon
• Park Young Ok
• Sung Su Jin

Classifications

• G02F1/3555

  Glasses · CPC title

• G02F1/167

  by electrophoresis · CPC title

• C03C21/002 Primary

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

• G02F1/133331

  Cover glasses · CPC title

• G09F9/30

  in which the desired character or characters are formed by combining individual elements (panels comprising a number of electrodes in a single cell controlling light arriving from an independent light source, e.g. electro-optical or magneto-optical cell, G02F1/00) · CPC title