US2948741A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of telomer acid
Assignee: 3M Co
•
Filing: 1956-03-21
•
Granted: 1960-08-09
•
Expires: 1976-03-21
Abstract
No abstract record available.
Inventors
- 👤 William S Barnhart
- 👤 Charles W Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 02:38
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/487
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
72 words
A METHOD FOR THE RECOVERY OF A PERCHLOROFLUOROALKYL CARBOXYLIC ACID FROM A DILUTE AQUEOUS SOLUTION CONTAINING AT LEAST 98 PERCENT BY WEIGHT OF WATER WHICH COMPRISES ADDING TO SAID DILUTE AQUEOUS SOLUTION OF A MEMBER OF THE GROUP CONSISTING OF SULFURIC AND PHOSPHORIC ACIDS IN SUFFICIENT QUANTITY TO FORM A SOLUTION OF ABOUT 1 TO 10 PERCENT BY WEIGHT OF ADDED ACID, THEREBY PRECIPITATING THE PERCHLOROFLUOROALKYL CARBOXYLIC ACID, AND SEPARATING THE PRECIPITATE.
Claim 2
Independent Claim
72 words
A METHOD FOR THE RECOVERY OF A PERCHLOROFLUOROALKYL CARBOXYLIC ACID FROM A DILUTE AQUEOUS SOLUTION CONTAINING AT LEAST 98 PERCENT BY WEIGHT OF WATER WHICH COMPRISES ADDING TO SAID DILUTE AQUEOUS SOLUTION OF A MEMBER OF THE GROUP CONSISTING OF SULFURIC AND PHOSPHORIC ACIDS IN SUFFICIENT QUANTITY TO FORM A SOLUTION OF ABOUT 1 TO 10 PERCENT BY WEIGHT OF ADDED ACID, THEREBY PRECIPITATING THE PERCHLOROFLUOROALKYL CARBOXYLIC ACID, AND SEPARATING THE PRECIPITATE.
References Cited (Backward Citations)
US2559629A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-08-09 | 1964-02-08 | 1964-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-08-09 | 1968-02-08 | 1968-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-08-09 | 1972-02-08 | 1972-08-09 | $7700.00 | Window Closed / Lapsed |