Patent US2607260A successfully refreshed from Google Patents.
Patent US2789140A successfully refreshed from Google Patents.
US2789140A
Expired / Lapsed
US
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Process of preparing tetra substituted 2, 2', 4, 4'-benzophenones
Assignee: GAF Chemicals Corp
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Filing: 1955-12-29
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Granted: 1957-04-16
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Expires: 1975-12-29
Abstract
No abstract record available.
Inventors
- 👤 Glahn William H Von
- 👤 Lester N Stanley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:14
CPC Classifications
C; C07; C07C; C07C45/00; C07C45/45; C07C45/47; C07C49/00; C07C49/76; C07C49/82; C07C49/83; C07C49/84
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
15 words
THE PROCESS OF PREPARING AT LEAST ONE TERA SUBSTITUTED 2M2'',4,4''-BENZOPHENONE HAVING THE FOLLOWING GENERAL FORMULA:
Claim 2
Dependent Claim
15 words
THE PROCESS OF PREPARING AT LEAST ONE TERA SUBSTITUTED 2M2'',4,4''-BENZOPHENONE HAVING THE FOLLOWING GENERAL FORMULA:
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) | 1960-04-15 | 1960-10-15 | 1961-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-04-15 | 1964-10-15 | 1965-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-04-15 | 1968-10-15 | 1969-04-16 | $7700.00 | Window Closed / Lapsed |