Claims
- 1. An alkali-free glass consisting essentially of, by wt %, from 58.4 to 66.0% of SiO2, from 15.3 to 22.0% of Al2O3, from 5.0 to 12.0% of B2O3, from 0 to 8.0% of MgO, from 0 to 9.0% of CaO, from 3.0 to 12.5% of SrO, from 0 to less than 2.0% of BaO, and from 9.0 to 18.0% of MgO+CaO+SrO+BaO and having a strain point of at least 640° C.
- 2. The alkali-free glass according to claim 1, wherein the amount of MgO is from more than 6.5 to 8.0 wt % and the amount of SrO is from 3.0 to less than 4.0 wt %.
- 3. The alkali-free glass according to claim 2, which has a density of less than 2.40 g/cc.
- 4. The alkali-free glass according to claim 1, wherein the amount of CaO is from more than 7.0 to 9.0 wt %.
- 5. The alkali-free glass according to claim 4, which has a Young's modulus of at least 7,400 kgf/mm2.
- 6. The alkali-free glass according to claim 1, wherein the amount of MgO is from more than 6.5 to 8.0 wt %, the amount of CaO is from more than 7.0 to 9.0 wt % and the amount of SrO is from 3.0 to less than 4.0 wt %.
- 7. The alkali-free glass according to claim 6, which has a density of less than 2.40 g/cc and a Young's modulus of at least 7,400 kgf/mm2.
- 8. The alkali-free glass according to claim 1, which contains substantially no PbO, As2O3 or Sb2O3.
- 9. The alkali-free glass according to claim 1, which has a density of less than 2.60 g/cc.
- 10. The alkali-free glass according to claim 1, which has a coefficient of thermal expansion of less than 40×10−7/° C.
- 11. The alkali-free glass according to claim 1, which is used for a display substrate.
- 12. A flat panel display comprising a pair of substrates constituting a cell, wherein at least one of the substrates is made of the alkali-free glass as defined in claim 1.
- 13. An alkali-free glass consisting essentially of, by wt %, from 58.4 to 66.0% of SiO2, from 15.3 to 22.0% of Al2O3, from 5.0 to 12.0% of B2O3, from 0 to 6.5% of MgO, from 0 to 7.0% of CaO, from 4.0 to 12.5% of SrO, from 0 to less than 2.0% of BaO, and from 9.0 to 18.0% of MgO+CaO+SrO+BaO and having a strain point of at least 640° C.
- 14. The alkali-free glass according to claim 13, which contains substantially no PbO, As2O3 or Sb2O3.
- 15. The alkali-free glass according to claim 13, which has a density of less than 2.60 g/cc.
- 16. The alkali-free glass according to claim 13, which has a coefficient of thermal expansion of less than 40×10−7/° C.
- 17. The alkali-free glass according to claim 13, wherein the content of phosphorus is not more than 20 ppm by atomic weight.
- 18. The alkali-free glass according to claim 13, which is used for a display substrate.
- 19. A flat panel display comprising a pair of substrates constituting a cell, wherein at least one of the substrates is made of the alkali-free glass as defined in claim 13.
Priority Claims (3)
Number |
Date |
Country |
Kind |
6-296522 |
Nov 1994 |
JP |
|
7-273234 |
Oct 1995 |
JP |
|
8-140305 |
Jun 1996 |
JP |
|
CROSS-REFERENCE TO RELATED APPLICATION
This application is a Continuation-in-part (CIP) of application Ser. No. 08/867,958 filed on Jun. 3, 1997, now abandoned which is a Continuation-In-Part of Ser. No. 08/669,797 filed Jun. 27, 1996, now U.S. Pat. No. 5,801,109, which is a a continuation of Ser. No. 08/563,824 filed Nov. 28, 1995, abandoned.
US Referenced Citations (4)
Number |
Name |
Date |
Kind |
5244847 |
Kushitani et al. |
Sep 1993 |
|
5348916 |
Kushitani et al. |
Sep 1994 |
|
5801109 |
Nishizawa et al. |
Sep 1998 |
|
5885914 |
Nishizawa et al. |
Mar 1999 |
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Foreign Referenced Citations (3)
Number |
Date |
Country |
9-169539 |
Jun 1997 |
JP |
9-169538 |
Jun 1997 |
JP |
10-72237 |
Mar 1998 |
JP |
Continuations (1)
|
Number |
Date |
Country |
Parent |
08/563824 |
Nov 1995 |
US |
Child |
08/669797 |
|
US |
Continuation in Parts (2)
|
Number |
Date |
Country |
Parent |
08/867958 |
Jun 1997 |
US |
Child |
09/268319 |
|
US |
Parent |
08/669797 |
Jun 1996 |
US |
Child |
08/867958 |
|
US |