US2581059A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of acylation
Assignee: GAF Chemicals Corp
•
Filing: 1948-06-29
•
Granted: 1952-01-01
•
Expires: 1968-06-29
Abstract
No abstract record available.
Inventors
- 👤 Witte Michael
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:50
CPC Classifications
C; C07; C07C; C07C39/00; C07C39/205; C07C39/21; C07C39/215
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
10 words
IN THE PROCESS OF DIACYLATING 4,4''-DIAMINOSTILBENE COMPOUNDS OF THE FORMULA:
Claim 2
Dependent Claim
10 words
IN THE PROCESS OF DIACYLATING 4,4''-DIAMINOSTILBENE COMPOUNDS OF THE FORMULA:
References Cited (Backward Citations)
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GB315200A
Cited
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Cited
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Cited
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Cited
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Cited
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Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-12-31 | 1955-07-02 | 1956-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-12-31 | 1959-07-02 | 1960-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-12-31 | 1963-07-02 | 1964-01-01 | $7700.00 | Window Closed / Lapsed |