US3349078A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of preparing sulfate esters of algin and products obtained thereby
Assignee: Kelco Co
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Filing: 1964-02-26
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Granted: 1967-10-24
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Expires: 1984-02-26
Abstract
No abstract record available.
Inventors
- 👤 Richard G Schweiger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:51
CPC Classifications
C; C08; C08B; C08B37/00; C08B37/006; C08B37/0084
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
67 words
A PROCESS OF FORMING A SULFATE ESTER OF ALGIN WHICH COMPRISES BRINGING TOGETHER ALGIN IN A SWOLLEN, DEHYDRATED ACTIVATED FORM, SULPHUR TRIOXIDE, AND SUFFICIENT OF AN NDIALKYL AMIDE TO FORM A COMPLEX WITH THE SAID SULPHUR TRIOXIDE, SO AS TO FORM A REACTION MIXTURE, AND ALLOWING SAID REACTION MIXTURE TO STAND UNTIL ESTERIFICATION HAS TAKEN PLACE TO A DEGREE OF SUBSTITUTION WITHIN THE RANGE 0.1 TO 1.9.
Claim 2
Dependent Claim
67 words
A PROCESS OF FORMING A SULFATE ESTER OF ALGIN WHICH COMPRISES BRINGING TOGETHER ALGIN IN A SWOLLEN, DEHYDRATED ACTIVATED FORM, SULPHUR TRIOXIDE, AND SUFFICIENT OF AN NDIALKYL AMIDE TO FORM A COMPLEX WITH THE SAID SULPHUR TRIOXIDE, SO AS TO FORM A REACTION MIXTURE, AND ALLOWING SAID REACTION MIXTURE TO STAND UNTIL ESTERIFICATION HAS TAKEN PLACE TO A DEGREE OF SUBSTITUTION WITHIN THE RANGE 0.1 TO 1.9.
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) | 1970-10-23 | 1971-04-24 | 1971-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-10-23 | 1975-04-24 | 1975-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-10-23 | 1979-04-24 | 1979-10-24 | $7700.00 | Window Closed / Lapsed |