Patent US2634259A successfully refreshed from Google Patents.
US2634259A
Expired / Lapsed
US
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Polymerization process for n-vinyl pyrrolidone
Assignee: Arnold Hoffman & Co Inc
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Filing: 1951-07-31
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Granted: 1953-04-07
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Expires: 1971-07-31
Abstract
No abstract record available.
Inventors
- 👤 Jr William O Ney
- 👤 William R Nummy
- 👤 Carl E Barnes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:45
CPC Classifications
C; C08; C08F; C08F10/00; C08F2/00; C08F2/04; C08F2/06; C08F2/38
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
50 words
THE PROCESS OF POLYMERIZING VINYL PYRROLIDONE IN THE PRESENCE OF A POLYMERIZATION INTIATOR WHICH IS FREE RADICAL SUPPLIER WHICH COMPRISES POLYMERIZING AT THE BOILING POINT AND PERMANENTLY DISTILLING OFF VAPORS CONTAINING SUBSTANTIALLY ALL OF THE ACETALDEHYDE AND ACETALDEHYDE COMPLEXES FORMED WHEREBY COLOR AND ODOR ARE ELIMINATED FROM THE POLYMERIZATION PRODUCT.
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) | 1956-04-06 | 1956-10-06 | 1957-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-04-06 | 1960-10-06 | 1961-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-04-06 | 1964-10-06 | 1965-04-07 | $7700.00 | Window Closed / Lapsed |