Patent US4874724A successfully refreshed from Google Patents.
US4874724A
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Alkali zinc aluminophosphate glass-ceramics
Assignee: Corning Inc
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Filing: 1988-10-17
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Granted: 1989-10-17
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Expires: 2008-10-17
Abstract
Abstract This invention is directed to the production of glass-ceramic articles exhibiting an apparent annealing point in excess of 400° C. and excellent resistance to moisture attack, the articles consisting essentially, in mole percent, of: ______________________________________ Li 2 O 5-25 ZnO 35-50 Na 2 O 0-15 Al 2 O 3 0.75-6 K 2 O 0-10 P 2 O 5 29-37. Li 2 O + Na 2 O + K 2 O 5-25 ______________________________________
Inventors
- 👤 George H. Beall
- 👤 Joseph E. Pierson
- 👤 Candace J. Quinn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:54
CPC Classifications
C; C03; C03C; C03C10/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
60 words
A glass-ceramic exhibiting an apparent annealing point greater than 400° C. and excellent resistance to moisture attack, said glass-ceramic consisting essentially, expressed in terms of mole percent on the oxide basis, of: ______________________________________
Li.sub.2 O 5-25 ZnO 35-50
Na.sub.2 O 0-15 Al.sub.2 O.sub.3
0.75-6
K.sub.2 O 0-10 P.sub.2 O.sub.5
29-37.
Li.sub.2 O + Na.sub.2 O + K.sub.2 O
5-25
______________________________________
Claim 2
Dependent Claim
60 words
A glass-ceramic exhibiting an apparent annealing point greater than 400° C. and excellent resistance to moisture attack, said glass-ceramic consisting essentially, expressed in terms of mole percent on the oxide basis, of: ______________________________________
Li.sub.2 O 5-25 ZnO 35-50
Na.sub.2 O 0-15 Al.sub.2 O.sub.3
0.75-6
K.sub.2 O 0-10 P.sub.2 O.sub.5
29-37.
Li.sub.2 O + Na.sub.2 O + K.sub.2 O
5-25
______________________________________
Claim 3
Dependent Claim
34 words
A glass-ceramic according to claim 1 also containing up to 5% total of at least one nucleating agent selected from the group consisting of AlF 3 , TiO 2 , and ZrO 2 .
Claim 4
Dependent Claim
50 words
A glass-ceramic according to claim 1 also containing up to 20% total of at least one member of the group in the indicated proportion of up to 10% total CaO, MgO, and/or MnO, up to 15% total Cu 2 O, PbO, and/or SnO, and up to 3% SiO 2 .
Claim 5
Dependent Claim
24 words
A glass-ceramic according to claim 3 wherein the total of CaO, MgO, MnO, Cu 2 O, PbO, and SiO 2 does not exceed 10%.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-16 | 1993-04-17 | 1993-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-16 | 1997-04-17 | 1997-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-16 | 2001-04-17 | 2001-10-17 | $7700.00 | Window Closed / Lapsed |