Patent US2953532A successfully refreshed from Google Patents.
US2953532A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cation exchangers of the polystyrene type
Assignee: Individual
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Filing: 1956-07-03
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Granted: 1960-09-20
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Expires: 1976-07-03
Abstract
No abstract record available.
Inventors
- 👤 Muhlberg Wolfgang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 03:38
CPC Classifications
B; B01; B01J; B01J39/00; B01J39/08; B01J39/16; B01J39/18; B01J39/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
131 words
THE PROCESS FOR PREPARING A CATION EXCHANGE MATERIAL COMPRISING SULFONATING POLYSTYRENE SUBSTANTIALLY FREE OF CROSS-LINKING IN THE FORM OF PELLETS OF A SIZE SUITABLE FOR USE AS EXCHANGE MATERIAL, BY SLOWLY HEATING THE POLYSTYRENE PELLETS WITH CHLOROSULFONIC ACID UP TO 100* C. WHILE STIRRING IN THE PROPORTION OF POLYSTYRENE TO ACID IN THE RANGE OF ABOUT 21/2 TO 3 PARTS BY WEIGHT OF THE ACID TO ONE PART BY WEIGHT OF THE POLYSTYRENE AND CROSS-LINKING PRODUCT OBTAINED BY INTRODUCING GASEOUS FORMALDEHYDE INTO THE STIRRED REACTION MASS IN THE PROPORTION OF POLYSTYRENE TO FORMADEHYDE IN THE RANGE OF 20 PARTS BY WEIGHT OF THE POLYSTYRENE TO ABOUT 3 TO 5 PARTS BY WEIGHT OF THE FORMALDEHYDE AND SLOWLY RAISING THE TEMPERATURE UP TO 120*C., THE CROSS-LINKING BEING EFFECTED IN A WATER-FREE ENVIRONMENT.
Claim 2
Dependent Claim
131 words
THE PROCESS FOR PREPARING A CATION EXCHANGE MATERIAL COMPRISING SULFONATING POLYSTYRENE SUBSTANTIALLY FREE OF CROSS-LINKING IN THE FORM OF PELLETS OF A SIZE SUITABLE FOR USE AS EXCHANGE MATERIAL, BY SLOWLY HEATING THE POLYSTYRENE PELLETS WITH CHLOROSULFONIC ACID UP TO 100* C. WHILE STIRRING IN THE PROPORTION OF POLYSTYRENE TO ACID IN THE RANGE OF ABOUT 21/2 TO 3 PARTS BY WEIGHT OF THE ACID TO ONE PART BY WEIGHT OF THE POLYSTYRENE AND CROSS-LINKING PRODUCT OBTAINED BY INTRODUCING GASEOUS FORMALDEHYDE INTO THE STIRRED REACTION MASS IN THE PROPORTION OF POLYSTYRENE TO FORMADEHYDE IN THE RANGE OF 20 PARTS BY WEIGHT OF THE POLYSTYRENE TO ABOUT 3 TO 5 PARTS BY WEIGHT OF THE FORMALDEHYDE AND SLOWLY RAISING THE TEMPERATURE UP TO 120*C., THE CROSS-LINKING BEING EFFECTED IN A WATER-FREE ENVIRONMENT.
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) | 1963-09-20 | 1964-03-21 | 1964-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-09-20 | 1968-03-21 | 1968-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-09-20 | 1972-03-21 | 1972-09-20 | $7700.00 | Window Closed / Lapsed |