Glass for a substrate

• US 6,313,052 B1
• Filed: 02/24/1999
• Issued: 11/06/2001
• Est. Priority Date: 02/27/1998
• Status: Expired due to Term

• Current Assignee: Asahi Glass Company, Limited (AGC, Inc.)
• Original Assignee: Asahi Glass Company, Limited (AGC, Inc.)
• Inventors: Nakashima, Tetsuya, Maeda, Kei, Nakao, Yasumasa
• Primary Examiner(s): Sample, David R
• Application Number:
  US09/256,213
• Time in Patent Office: 986 Days
• Field of Search: 501/69, 501/70, 501/72
• US Class Current: 501/69
• CPC Class Codes: C03C 3/085 containing an oxide of a divalent metal
• CPC Class Codes: C03C 3/087 containing calcium oxide, e.g. common sheet or container glass
• CPC Class Codes: H01J 17/16 Vessels; Containers
• CPC Class Codes: H01J 2217/49264 Vessels
• CPC Class Codes: H01L 31/0392 including thin films deposited on metallic or insulating substrates ; characterised by specific substrate materials or substrate features or by the presence of intermediate layers, e.g. barrier layers, on the substrate textured substrates H01L31/02366
• CPC Class Codes: H01L 31/03921 including only elements of Group IV of the Periodic Table
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

A glass for a substrate, having an average thermal expansion coefficient in the range of from 60×10⁻⁷ to 75×10⁻⁷/° C. at 50 to 350° C., which consists essentially of the following composition expressed by wt %:

wt % SiO₂ more than 62 to 74, Al₂O₃  1 to 15, MgO  0 to 9, CaO  0 to 14, Na₂O  0 to 12, K₂O  0 to 13, SiO₂ + Al₂O₃ 72 to 82, MgO + CaO  5 to 24, Na₂O + K₂O  1 to 15, MgO + CaO + Na₂O + K₂O 18 to 28.

Claims

1. A glass for a substrate, the glass having an average thermal expansion coefficient in a range of from 60×

10<sup>−

7</sup> to 74×

10<sup>−

7</sup>/°

C. at 50 to 350°

C. and a specific gravity of at most 2.55, wherein the glass consists essentially of the following composition expressed in wt %;

2. The glass according to claim 1, wherein the glass consists essentially of:

3. The glass according to claim 1, wherein the glass consists essentially of:

4. The glass according to claim 1, wherein the glass consists essentially of:

5. The glass according to claim 1, wherein the glass is part of a field emission display.

6. The glass according to claim 1, wherein the glass is part of a plasma display panel.

7. The glass according to claim 1, wherein a viscosity of the glass is 10⁴ at a temperature of at most 1300°

C.

8. The glass according to claim 1, wherein a liquidus temperature of the glass is not higher than a temperature at which a viscosity of glass is 10⁴ poise.

9. The glass according to claim 1, wherein a glass transition temperature of the glass is at least 640°

C.

10. A method of making a glass, the method comprising melting raw materials, and forming the glass of claim 1.