Crystallized glass substrate

Patent metadata

Field	Value
Publication number	US-11926561-B2
Application number	US-201817266996-A
Country	US
Kind code	B2
Filing date	Aug 9, 2018
Priority date	Aug 9, 2018
Publication date	Mar 12, 2024
Grant date	Mar 12, 2024

Abstract

To provide a crystallized glass substrate including a surface with a compressive stress layer, in which a compressive stress CS (MPa) on an outermost surface of the compressive stress layer is 400 to 1400 MPa, and DOL50%/DOLzero is 0.30 or more, where DOL50% (μm) is a depth at which the value of the compressive stress is 50% of the CS and DOLzero (μm) is a depth at which the value of the compressive stress is 0 MPa.

First claim

What is claimed is:

1. A crystallized glass substrate including a surface with a compressive stress layer, wherein
a compressive stress CS (MPa) on an outermost surface of the compressive stress layer is 400 to 1400 MPa, and
DOL 50% /DOL zero is 0.30 or more, where DOL 50% (μm) is a depth at which the value of the compressive stress is 50% of the CS and DOL zero (μm) is a depth at which the value of the compressive stress is 0 MPa.

2. The crystallized glass substrate according to claim 1 , wherein a sum of the depths DOL zero from both surfaces of the crystallized glass substrate, 2DOL zero , is 10 to 80% of a thickness T of the crystallized glass substrate.

3. The crystallized glass substrate according to claim 1 , comprising: by wt % in terms of oxide,
40.0% to 70.0% of a SiO 2 component;
11.0% to 25.0% of an Al 2 O 3 component;
5.0% to 19.0% of a Na 2 O component;
0% to 9.0% of a K 2 O component;
1.0% to 18.0% of one or more selected from a MgO component and a ZnO component;
0% to 3.0% of a CaO component; and
0.5% to 12.0% of a TiO 2 component.

4. The crystallized glass substrate according to claim 1 , wherein a thickness T of the crystallized glass substrate is 0.1 to 1.0 mm.

5. The crystallized glass substrate according to claim 1 , wherein E/p, which is a ratio of Young's modulus E (GPa) to a specific gravity p, is 31 or more.

6. The crystallized glass substrate according to claim 1 , wherein a sum of the compressive stress CS on the outermost surface and a central stress CT determined by curve analysis is 600 to 1400 MPa.

7. The crystallized glass substrate according to claim 1 , wherein the depth DOL zero is 70 to 110 μm,
the compressive stress CS of the outermost surface is 550 to 890 MPa,
the central stress CT is 100 to 250 MPa, and
a sum of the compressive stress CS on the outermost surface and the central stress
CT is 800 to 1200 MPa.

8. The crystallized glass substrate according to claim 1 , wherein the depth DOL zero is 65 to 85 μm,
the compressive stress CS on the outermost surface is 700 to 860 MPa,
the central stress CT is 120 to 240 MPa, and
a thickness T of the crystallized glass substrate is 0.15 to 0.7 mm.

Assignees

• Ohara Kk

Inventors

• Yagi Toshitaka
• OGASAWARA Kohei
• MOTOSHIMA Yuki
• KOJIMA Reika
• Yamashita Yutaka
• Goto Naoyuki

Classifications

• C03C3/087 Primary

  containing calcium oxide, e.g. common sheet or container glass · CPC title

• C03C21/002 Primary

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

• C03C10/0045 Primary

  containing SiO2, Al2O3 and MgO as main constituents · CPC title

• C03C3/093

  containing zinc or zirconium · CPC title

• C03C3/085

  containing an oxide of a divalent metal · CPC title