CRYSTALLIZED GLASS SUBSTRATE

• US 20200131079A1
• Filed: 04/10/2018
• Published: 04/30/2020
• Est. Priority Date: 06/26/2017
• Status: Active Grant

• Current Assignee: Ohara Incorporated
• Original Assignee: Ohara Incorporated
• Inventors: YAGI, TOSHITAKA, YAMASHITA, YUTAKA, GOTO, NAOYUKI
• Granted Patent: US 11,104,603 B2
• Time in Patent Office: Days
• CPC Class Codes: C03C 10/0018 containing SiO2, Al2O3 and monovalent metal oxide as main constituents
• CPC Class Codes: C03C 10/0045 containing SiO2, Al2O3 and MgO as main constituents
• 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 3/087 containing calcium oxide, e.g. common sheet or container glass
• CPC Class Codes: C03C 4/18 for ion-sensitive glass

Abstract

A crystallized glass substrate includes a crystallized glass serving as a base material and a compressive stress layer forming a surface thereof. The crystallized glass contains, in % by weight on an oxide basis, 40.0% to 70.0% of a SiO₂ component, 11.0% to 25.0% of an Al₂O₃ component, 5.0% to 19.0% of a Na₂O component, 0% to 9.0% of a K₂O 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 TiO₂ component. The SiO₂ component, the Al₂O₃ component, the Na₂O component, the one or more selected from the MgO component and the ZnO component, and the TiO₂ component are present in a total amount of 90% or more.

Claims

1. A crystallized glass substrate comprising a crystallized glass serving as a base material and a compressive stress layer forming a surface thereof, the crystallized glass containing, in % by weight on an oxide basis:

40.0% to 70.0% of a SiO₂ component;

11.0% to 25.0% of an Al₂O₃ component;

5.0% to 19.0% of a Na₂O component;

0% to 9.0% of a K₂O 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 TiO₂ component,

the SiO₂ component, the Al₂O₃ component, the Na₂O component, the one or more selected from the MgO component and the ZnO component, and the TiO₂ component being present in a total amount of 90% or more,

wherein the compressive stress layer has a depth of layer of 40 μ

m or more,

the compressive stress layer has a surface compressive stress of 750 MPa or more, and

the compressive stress layer has a central compressive stress of 65 MPa or less as determined by curve analysis.

2. The crystallized glass substrate according to claim 1, wherein the surface compressive stress is 900 MPa or more.

3. The crystallized glass substrate according to claim 1, wherein the crystallized glass substrate has a thickness of 0.05 to 2.0 mm.

4. The crystallized glass substrate according to claim 1, wherein the crystallized glass base material contains, in % by weight on an oxide basis:

45.0% to 65.0% of the SiO₂ component;

13.0% to 23.0% of the Al₂O₃ component;

8.0% to 16.0% of the Na₂O component;

0% to 7.0% of the K₂O component;

2.0% to 15.0% of the one or more selected from the MgO component and the ZnO component;

0% to 2.0% of the CaO component; and

1.0% to 10.0% of the TiO₂ component,

the SiO₂ component, the Al₂O₃ component, the Na₂O component, the one or more selected from the MgO component and the ZnO component, and the TiO₂ component being present in a total amount of 90% or more.