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US2155673A
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Anthraquinone products and method of making
Assignee: National Aniline and Chemical Co Inc
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Filing: 1937-02-02
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Granted: 1939-04-25
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Expires: 1957-02-02
Abstract
No abstract record available.
Inventors
- 👤 Miller Alfred
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:31
CPC Classifications
C; C09; C09B; C09B1/00; C09B1/16; C09B1/20; C09B1/36
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) | 1942-04-24 | 1942-10-24 | 1943-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-04-24 | 1946-10-24 | 1947-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-04-24 | 1950-10-24 | 1951-04-25 | $7700.00 | Window Closed / Lapsed |