US3184476A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for removing endogenous activators from pyrrolidone
Assignee: 3M Co
•
Filing: 1961-09-05
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Granted: 1965-05-18
•
Expires: 1981-09-05
Abstract
No abstract record available.
Inventors
- 👤 Harold T Wingfield
- 👤 Oiye Benji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:08
CPC Classifications
C; C07; C07D; C07D201/00; C07D201/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
75 words
THE PROCESS FOR HYDROLYZING 1-(1-PYRROLIN-2-YL)-2PYRROLIDIMONE IN 2-PYRROLIDONE CONTAINING THE SAME TO GIVE 2-PYRROLIDONE WHICH COMPRISES THE STEP OF HEATING SAID 2-PYRROLIDONE CONTAINING 1-(1-PYRROLIN-2-YL)-2-PYRROLIDINONE WITH FROM ABOUT 3 TO ABOUT 25 PERCENT BY WEIGHT OF WATER AT A TEMPERATURE IN THE RANGE OF FROM ABOUT 80* TO 200* C. FOR A PERIOD RANGING FROM ABOUT 15 MINUTES UP TO ABOUT 16 HOURS, LONGER PERIODS BEING EMPLOYED WITH LOWER TEMPERATURES AND SHORTER PERIODS WITH MORE ELEVATED TEMPERATURES.
Claim 2
Dependent Claim
75 words
THE PROCESS FOR HYDROLYZING 1-(1-PYRROLIN-2-YL)-2PYRROLIDIMONE IN 2-PYRROLIDONE CONTAINING THE SAME TO GIVE 2-PYRROLIDONE WHICH COMPRISES THE STEP OF HEATING SAID 2-PYRROLIDONE CONTAINING 1-(1-PYRROLIN-2-YL)-2-PYRROLIDINONE WITH FROM ABOUT 3 TO ABOUT 25 PERCENT BY WEIGHT OF WATER AT A TEMPERATURE IN THE RANGE OF FROM ABOUT 80* TO 200* C. FOR A PERIOD RANGING FROM ABOUT 15 MINUTES UP TO ABOUT 16 HOURS, LONGER PERIODS BEING EMPLOYED WITH LOWER TEMPERATURES AND SHORTER PERIODS WITH MORE ELEVATED TEMPERATURES.
References Cited (Backward Citations)
US3040004A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-05-17 | 1968-11-16 | 1969-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-05-17 | 1972-11-16 | 1973-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-05-17 | 1976-11-16 | 1977-05-18 | $7700.00 | Window Closed / Lapsed |