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US1591688A
Expired / Lapsed
US
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Benzidine flakes
Assignee: National Aniline and Chemical Co Inc
•
Filing: 1923-06-18
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Granted: 1926-07-06
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Expires: 1943-06-18
Abstract
No abstract record available.
Inventors
- 👤 William L Spalding
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:21
CPC Classifications
C; C07; C07C; C07C211/00; C07C211/43; C07C211/54; Y; Y10; Y10S; Y10S159/00; Y10S159/23
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) | 1929-07-05 | 1930-01-04 | 1930-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1933-07-05 | 1934-01-04 | 1934-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1937-07-05 | 1938-01-04 | 1938-07-06 | $7700.00 | Window Closed / Lapsed |