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US3557200A
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US
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Nitrilotriacetic acid based chelating agents
Assignee: Individual
•
Filing: 1967-08-17
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Granted: 1971-01-19
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Expires: 1987-08-17
Abstract
Abstract CHELATING AGENTS ARE PREPARED BY REACTING AMMONIA WITH NITRILOTRIACETIC ACID TO FORM A CONDENSATION PRODUCT WHICH HAS CHELATING PROPERTIES SUITABLE FOR HOLDING IRON IONS IN AQUEOUS SOLUTION OVER THE COMPLETE TEMPERATURE AND PH RANGE ATTAINABLE IN AQUEOUS SOLUTION.
Inventors
- 👤 Frederick C Bersworth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:27
CPC Classifications
C; C07; C07C; C07C227/00; C07C227/14; C07C227/18; Y; Y10; Y10S; Y10S71/00; Y10S71/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |