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US2537880A
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Process for preparing polymethine dyes
Assignee: Eastman Kodak Co
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Filing: 1949-01-13
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Granted: 1951-01-09
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Expires: 1969-01-13
Abstract
No abstract record available.
Inventors
- 👤 Jr Samuel G Dent
- 👤 Leslie G S Brooker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 05:04
CPC Classifications
C; C09; C09B; C09B23/00; C09B23/12; C09B23/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
34 words
A PROCESS FOR PREPARING A POLYMETHINE DYE COMPRISING CONDENSING A CYCLAMMONIUM QUATERNARY SALT CONTAINING A METHYL GROUP IN A REACTIVE POSITION, WITH A DIALKOXYMETHYL CARBOXYLATE SELECTED FROM THOSE REPRESENTED BY THE FOLLOWING GENERAL FORMULA:
Claim 2
Dependent Claim
34 words
A PROCESS FOR PREPARING A POLYMETHINE DYE COMPRISING CONDENSING A CYCLAMMONIUM QUATERNARY SALT CONTAINING A METHYL GROUP IN A REACTIVE POSITION, WITH A DIALKOXYMETHYL CARBOXYLATE SELECTED FROM THOSE REPRESENTED BY THE FOLLOWING GENERAL FORMULA:
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) | 1954-01-08 | 1954-07-10 | 1955-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-08 | 1958-07-10 | 1959-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-08 | 1962-07-10 | 1963-01-09 | $7700.00 | Window Closed / Lapsed |