Patent US2521705A successfully refreshed from Google Patents.
US2521705A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cyanine dyes
Assignee: EIDP Inc
•
Filing: 1946-08-21
•
Granted: 1950-09-12
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Expires: 1966-08-21
Abstract
No abstract record available.
Inventors
- 👤 Firestine John Charles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:49
CPC Classifications
C; C09; C09B; C09B23/00; C09B23/02; C09B23/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
7 words
A CHEMICAL COMPOUND OF THE GENERAL FORMULA:
Claim 2
Dependent Claim
7 words
A CHEMICAL COMPOUND OF THE GENERAL FORMULA:
References Cited (Backward Citations)
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Cited
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US2068047A
Cited
US2173486A
Cited
US1962124A
Cited
US2323504A
Cited
US2350393A
Cited
US2362337A
Cited
US2415927A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-09-11 | 1954-03-13 | 1954-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-11 | 1958-03-13 | 1958-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-11 | 1962-03-13 | 1962-09-12 | $7700.00 | Window Closed / Lapsed |