Patent US3756838A successfully refreshed from Google Patents.
US3756838A
Expired / Lapsed
US
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Strontium fluormica glass ceramics
Assignee: Corning Glass Works
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Filing: 1971-05-28
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Granted: 1973-09-04
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Expires: 1991-05-28
Abstract
Abstract THE INVENTION RELATES TO THE PRODUCTION OF GLASSCERAMIC ARTICLES WHEREIN THE PREDOMINANT CRYSTAL PHASE IS AN ESSENTIALLY ALKALI METAL-FREE FLUORMICA. SUCH ARTICLE ARE MACHINABLE WITH NORMAL METAL TOOLS AND CONSIST ESSENTIALLY, BY WEIGHT ON THE OXIDE BASIS, OF ABOUT 3-30% SRO, 10-35% MGO, 5-26% AL2O3, 30-65% SIO2, AND 3-15% F. CERTAIN OF THE THESE GLASS-CERAMIC BODIES ALSO EXHIBIT WATER-SWELLING EVEN IN CONTACT WITH COLD WATER. THESE WATER-SWELLING FLUORMICA GLASS-CERMAIC BODIES CONSIST ESSENTIALLY, BY WEIGHT ON THE OXIDE BASIC, OF ABOUT 8-30% SRO, 10-35% MGO, 5-26% AL2O2, 30-60% SIO2, AND 3-15% F.
Inventors
- 👤 G Beall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 04:06
CPC Classifications
C; C03; C03C; C03C10/00; C03C10/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |