US2531468A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyvinyl sulfonates and process for their preparation
Assignee: Eastman Kodak Co
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Filing: 1949-04-14
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Granted: 1950-11-28
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Expires: 1969-04-14
Abstract
No abstract record available.
Inventors
- 👤 Delbert D Reynolds
- 👤 William O Kenyon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 00:51
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/34; C08F8/36; C08F8/30; C08F8/32
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
46 words
A PROCESS FOR PREPARING APOLYVINYL SULFONATES COMPRISING SWELLING POLYVINYL ALCOHOL BY HEATING THE POLYVINYL ALCOHOL IN PYRIDINE AT A TEMPERATURE OF FROM 50* TO 115*C., COOLING THE POLYVINYL ALCOHOL-PRYRIDINE MIXTURE TO FROM 0* TO 20* C. AND THEN ADDING A SULFONATING AGENT HAVING THE GENERAL FORMULA:
Claim 2
Dependent Claim
46 words
A PROCESS FOR PREPARING APOLYVINYL SULFONATES COMPRISING SWELLING POLYVINYL ALCOHOL BY HEATING THE POLYVINYL ALCOHOL IN PYRIDINE AT A TEMPERATURE OF FROM 50* TO 115*C., COOLING THE POLYVINYL ALCOHOL-PRYRIDINE MIXTURE TO FROM 0* TO 20* C. AND THEN ADDING A SULFONATING AGENT HAVING THE GENERAL FORMULA:
References Cited (Backward Citations)
US2395347A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-11-27 | 1954-05-29 | 1954-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-11-27 | 1958-05-29 | 1958-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-11-27 | 1962-05-29 | 1962-11-28 | $7700.00 | Window Closed / Lapsed |