Patent US3667973A successfully refreshed from Google Patents.
US3667973A
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Spontaneous fluoride opal glasses with thermally reversible opacity
Assignee: Corning Glass Works
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Filing: 1970-10-09
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Granted: 1972-06-06
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Expires: 1990-10-09
Abstract
Abstract THIS INVENTION RELATES TO THE MANUFACTURE OF SPONTANEOUS ALKALI METAL FLUORIDE OPAL GLASSES CONTAINING OPACITY DENSIFYING AGENTS AND EXHIBITING THERMALLY REVERSIBLE OPACITY; THAT IS, THEY MAY BE HEATED TO CLEARNESS AND COOLED TO OPACITY WITHOUT DEFORMATION OF THE GLASS BEING HEATED. OPERATIVE COMPOSITIONS INCLUDE GLASSES CONSISTING ESSENTIALLY, BY WEIGHT ON THE OXIDE BASIS OF 70-80% SIO2, 1-3% AL2O3, 7-14% B2O3, 1.5-4% LI2O, O-10% R2O WHEREIN R2O IS AT LEAST ONE ALKALI METAL OXIDE SELECTED FROM THE GROUP CONSISTING OF K2O AND NA2O, 3-6% F, AND A TOTAL OF 1-3% OF AN OPACITY DENSIFYING AGENT SELECTED FROM THE GROUP CONSISTING OF MOO3, WO3, AND AS2O3.
Inventors
- 👤 James E Flannery
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:36
CPC Classifications
C; C03; C03C; C03C4/00; C03C4/005; C03C3/00; C03C3/04; C03C3/076; C03C3/11; C03C3/112; C03C3/115; C03C3/118; C03C2204/00; C03C2204/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-06 | 1975-12-06 | 1976-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-06 | 1979-12-06 | 1980-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-06 | 1983-12-06 | 1984-06-06 | $7700.00 | Window Closed / Lapsed |