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Patent US2117359A successfully refreshed from Google Patents.
US2117359A
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Phthalic anhydride production
Assignee: Solvay Process Co
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Filing: 1937-08-17
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Granted: 1938-05-17
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Expires: 1957-08-17
Abstract
No abstract record available.
Inventors
- 👤 Porter Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:08
CPC Classifications
B; B01; B01J; B01J8/00; B01J8/02; C; C07; C07C; C07C51/00; C07C51/16; C07C51/31; C07C51/313; B01J2208/00; B01J2208/00008; B01J2208/00017; B01J2208/00106; B01J2208/00168; B01J2208/00212; B01J2208/00265; B01J2208/00283; B01J2208/00477; B01J2208/00495; B01J2208/0053; B01J2208/00539
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) | 1941-05-16 | 1941-11-15 | 1942-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1945-05-16 | 1945-11-15 | 1946-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1949-05-16 | 1949-11-15 | 1950-05-17 | $7700.00 | Window Closed / Lapsed |