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Patent US2688469A successfully refreshed from Google Patents.
US2688469A
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Method and apparatus for refining molten glass
Assignee: PPG Industries Inc
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Filing: 1951-11-01
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Granted: 1954-09-07
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Expires: 1971-11-01
Abstract
No abstract record available.
Inventors
- 👤 Frederick R Hohmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:32
CPC Classifications
C; C03; C03B; C03B5/00; C03B5/16; C03B5/18; C03B5/182; C03B5/187; C03B5/1875
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
FR711976A
Cited
US1982002A
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US2072807A
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US2040789A
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US2212528A
Cited
FR831332A
Cited
US2411031A
Cited
US2515481A
Cited
US2515478A
Cited
US2569459A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-09-06 | 1958-03-08 | 1958-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-09-06 | 1962-03-08 | 1962-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-09-06 | 1966-03-08 | 1966-09-07 | $7700.00 | Window Closed / Lapsed |