US2542401A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cyanine dyestuffs
Assignee: Ilford Imaging UK Ltd
•
Filing: 1948-01-21
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Granted: 1951-02-20
•
Expires: 1968-01-21
Abstract
No abstract record available.
Inventors
- 👤 Doyle Frank Peter
- 👤 Kendall John David
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:57
CPC Classifications
C; C09; C09B; C09B23/00; C09B23/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
26 words
A PROCESS FOR THE PRODUCTION OF CYANINE DYES WHICH COMPRISES CONDENSING TOGETHER 2-CYANMETHYLENE -3- METHYL - DIHYDROBENZTHIAZOLE AND 2(W-EHTHYLTHIO-VINYL) -5-CHLORBENZTHIAZOLE-METHOP-TOLUENE SULPHONATE IN THE PRESENCE OF PYRIDINE.
Claim 2
Dependent Claim
26 words
A PROCESS FOR THE PRODUCTION OF CYANINE DYES WHICH COMPRISES CONDENSING TOGETHER 2-CYANMETHYLENE -3- METHYL - DIHYDROBENZTHIAZOLE AND 2(W-EHTHYLTHIO-VINYL) -5-CHLORBENZTHIAZOLE-METHOP-TOLUENE SULPHONATE IN THE PRESENCE OF PYRIDINE.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-02-19 | 1954-08-21 | 1955-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-19 | 1958-08-21 | 1959-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-19 | 1962-08-21 | 1963-02-20 | $7700.00 | Window Closed / Lapsed |