# US 2019/0375680 A1 · Crystallized glass

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2019/0375680 A1
- Document ID: US20190375680A1
- Status: Published application
- Kind: A1
- Application number: 16/488,248
- Filed: 2017-12-28
- Published: 2019-12-12
- Earliest claimed: 2017-02-24
- Assignees: Ohara Inc.
- Applicants: Ohara Inc.
- Inventors: TOSHITAKA YAGI; YUTAKA YAMASHITA; NAOYUKI GOTO
- Web page: https://patentgrep.com/patent/US20190375680A1

## CPC

- C03C 21/002: {to perform ion-exchange between alkali ions (C03C21/005 takes precedence)}
- C03C 3/087: containing calcium oxide, e.g. common sheet or container glass
- C03C 4/0092: {for glass with improved high visible transmittance, e.g. extra-clear glass}
- C03C 10/0045: {containing SiO2, Al2O3 and MgO as main constituents}
- C03C: CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS

## Abstract

A crystallized glass includes a crystallized glass mother material, and, in a surface, a compressive stress layer, wherein the crystallized glass has, for a thickness of 10 mm, a light transmittance of, including reflection loss, 80% at a wavelength in 400 to 669 nm, and has a Vickers hardness [Hv] of 835 to 1300. In the crystallized glass, the crystallized glass mother material 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 a MgO component, 0% to 3.0% of a CaO component, and 0.5% to 12.0% of a TiO2 component, and a total content of the SiO2 component, the Al2O3 component, the Na2O component, the K2O component, the MgO component, and the TiO2 component is 90% or more.

## Claims

### Claim 1

A crystallized glass comprising a crystallized glass mother material, and, in a surface, a compressive stress layer,
wherein the crystallized glass has, for a thickness of 10 mm, a light transmittance of, including reflection loss, 80% at a wavelength in 400 to 669 nm, and has a Vickers hardness [Hv] of 835 to 1300.

### Claim 2 (depends on 1)

The crystallized glass according to claim 1, wherein the compressive stress layer has a thickness of 20 μm or more.

### Claim 3 (depends on 1)

The crystallized glass according to claim 1, wherein the crystallized glass mother material 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 a MgO component,
0% to 3.0% of a CaO component, and
0.5% to 12.0% of a TiO2 component, and
a total content of the SiO2 component, the Al2O3 component, the Na2O component, the K2O component, the MgO component, and the TiO2 component is 90% or more.

### Claim 4 (depends on 1)

The crystallized glass according to claim 1, wherein the crystallized glass mother material contains, in % by weight on an oxide basis,
45.0% to 65.0% of a SiO2 component,
13.0% to 23.0% of an Al2O3 component,
8.0% to 16.0% of a Na2O component,
1.0% to 7.0% of a K2O component,
2.0% to 15.0% of a MgO component,
0.1% to 2.0% of a CaO component,
1.0% to 10.0% of a TiO2 component, and
0.1% to 2.0% of one or more selected from the group consisting of an Sb2O3 component, a SnO2 component, and a CeO2 component, and
a total content of the SiO2 component, the Al2O3 component, the Na2O component, the K2O component, the MgO component, and the TiO2 component is 90% or more.

### Claim 5 (depends on 1)

The crystallized glass according to claim 1, wherein precipitated crystals have an average crystal size of 4 to 15 nm.