Crystallized glass substrate

Patent metadata

Field	Value
Publication number	US-11926559-B2
Application number	US-202318154042-A
Country	US
Kind code	B2
Filing date	Jan 13, 2023
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 stress depth DOL zero of the compressive stress layer, at which the compressive stress is 0 MPa, is 45 to 200 μm, a compressive stress CS on an outermost surface of the compressive stress layer is 400 to 1400 MPa, and CS×DOL zero , which is a product of the compressive stress CS on the outermost surface and the stress depth DOL zero (μm), is 4.8×10 4 or more.

First claim

What is claimed is:

1. A crystallized glass substrate including a surface with a compressive stress layer, wherein
a stress depth DOL zero of the compressive stress layer is 45 to 200 μm, the stress depth DOL zero being a depth at which the compressive stress is 0 MPa,
a compressive stress CS on an outermost surface of the compressive stress layer is 400 to 1400 MPa,
CS×DOL zero , which is a product of the compressive stress CS on the outermost surface and the stress depth DOL zero (μm), is 4.8×10 4 or more, and
the crystallized glass substrate comprises, by wt % in terms of oxide:
5.0% or more of a Na 2 O component; and
2.0% or more of a TiO 2 component.

2. The crystallized glass substrate according to claim 1 , wherein a sum of the stress depths from both surfaces of the crystallized glass substrate, 2×DOL 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
2.0% 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/ρ, which is a ratio of Young's modulus E(GPa) to a specific gravity ρ, 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 stress 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 stress 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

• C03C21/002 Primary

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

• C03C4/18

  for ion-sensitive glass · CPC title

• C03C10/0018

  containing SiO2, Al2O3 and monovalent metal oxide as main constituents · CPC title

• C03C2204/00

  Glasses, glazes or enamels with special properties · CPC title

• C03C3/085 Primary

  containing an oxide of a divalent metal · CPC title