GLASS SUBSTRATE

• US 20200131075A1
• Filed: 04/12/2018
• Published: 04/30/2020
• Est. Priority Date: 04/27/2017
• Status: Active Grant

• Current Assignee: Nippon Electric Glass Company Limited
• Original Assignee: Nippon Electric Glass Company Limited
• Inventors: SAITO, Atsuki
• Granted Patent: US 11,427,496 B2
• Time in Patent Office: Days
• CPC Class Codes: C03B 17/06 Forming glass sheets
• CPC Class Codes: C03B 5/027 by passing an electric current between electrodes immersed in the glass bath, i.e. by direct resistance heating
• CPC Class Codes: C03B 5/43 Use of materials for furnace walls, e.g. fire-bricks
• CPC Class Codes: C03C 3/087 containing calcium oxide, e.g. common sheet or container glass
• CPC Class Codes: C03C 3/091 containing aluminium
• CPC Class Codes: H10K 50/00 Organic light-emitting devices integrated devices or assemblies of multiple devices H10K59/00, H10K65/00; organic semiconductor lasers H01S5/36
• CPC Class Codes: Y02P 40/57 Improving the yield, e-g- reduction of reject rates

Abstract

A glass substrate of the present invention has a temperature at a viscosity at high temperature of 10^2.5 dPa·s of 1,650° C. or less, and an estimated viscosity Log η₅₀₀ at 500° C. of 26.0 or more calculated by the equation Log η₅₀₀=0.167×Ps-0.015×Ta-0.062×Ts-18.5.

Claims

1. A glass substrate, which has a temperature at a viscosity at high temperature of 10^2.5 poise of 1,670°

C. or less, and an estimated viscosity Log η

₅₀₀ at 500°

C. of 26.0 or more calculated by the following equation.

Log η

₅₀₀=0.167×

Ps-0.015×

Ta-0.062×

Ts-18.5

Ps;

strain point (°

C.)

Ta;

annealing point (°

C.)

Ts;

softening point (°

C.)

2. The glass substrate according to claim 1, wherein the glass substrate has a value A of 25.0 or more calculated by the following equation.

Value A=Log η

₅₀₀-[β

-OH value (mm<sup>−

1</sup>)]×

[content of B₂O₃ (mass %)]

3. The glass substrate according to claim 1, wherein the glass substrate has a β

-OH value of 0.20/mm or less.

4. The glass substrate according to claim 1, wherein the glass substrate has a β

-OH value of 0.15/mm or less.

5. The glass substrate according to claim 1, wherein the glass substrate has a content of B₂O₃ of less than 2.0 mass %.

6. The glass substrate according to claim 1, wherein the glass substrate comprises as a glass composition, in terms of mass %, 55% to 65% of SiO₂, 16% to 22% of Al₂O₃, 0% to 1% of B₂O₃, 0% to less than 0.1% of Li₂O+Na₂O+K₂O, 1% to 6% of MgO, 2% to 8% of CaO, 0% to 2% of SrO, 4% to 13% of BaO, 0% to less than 0.010% of AsO₃, and 0% to less than 0.010% of Sb₂O₃.

7. The glass substrate according to claim 1, wherein the glass substrate has a content of Fe₂O₃ in a glass composition of 0.010 mass % or less.

8. The glass substrate according to claim 1, wherein the glass substrate has a liquidus temperature of 1,300°

C. or less.

9. The glass substrate according to claim 1, wherein the glass substrate comprises a formed joined surface in a center portion in a thickness direction.

10. The glass substrate according to claim 1, wherein the glass substrate is used as a substrate of an OLED device.

11. The glass substrate according to claim 2, wherein the glass substrate has a β

-OH value of 0.20/mm or less.