US2956892A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Glass composition
Assignee: PPG Industries Inc
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Filing: 1957-10-25
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Granted: 1960-10-18
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Expires: 1977-10-25
Abstract
No abstract record available.
Inventors
- 👤 James E Duncan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:48
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/04; C03C3/076; C03C3/11; C03C3/112; C03C1/00; C03C1/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
76 words
A BLUE TO GRAY COLORED, OPAQUE GLASS CONSISTING ESSENTIALLY OF THE FOLLOWING INGREDIENTS IN PERCENT BY WEIGHT: 55 TO 75% SIO2, 5 TO 15% NA2O, TO 10% K2O, THE SUM TOTAL OF ALKALI METAL OXIDES BEING BETWEEN 11 AND, 21%, 2 TO 12% A12O3, UP TO 2% OF AT LEAST ONE OF THE GROUP CONSISTING OF SB2O5 AND AS2O5, 0.05 TO 0.5% NIO, 0.05 TO 0.5% CR2O3, 0.001 TO 0.1% COO AND 1 TO 6% F2.
Claim 2
Dependent Claim
76 words
A BLUE TO GRAY COLORED, OPAQUE GLASS CONSISTING ESSENTIALLY OF THE FOLLOWING INGREDIENTS IN PERCENT BY WEIGHT: 55 TO 75% SIO2, 5 TO 15% NA2O, TO 10% K2O, THE SUM TOTAL OF ALKALI METAL OXIDES BEING BETWEEN 11 AND, 21%, 2 TO 12% A12O3, UP TO 2% OF AT LEAST ONE OF THE GROUP CONSISTING OF SB2O5 AND AS2O5, 0.05 TO 0.5% NIO, 0.05 TO 0.5% CR2O3, 0.001 TO 0.1% COO AND 1 TO 6% F2.
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) | 1963-10-18 | 1964-04-18 | 1964-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-10-18 | 1968-04-18 | 1968-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-10-18 | 1972-04-18 | 1972-10-18 | $7700.00 | Window Closed / Lapsed |