US3661985A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of non-caking urea
Assignee: Azote et Produits Chimiques SA
•
Filing: 1969-01-02
•
Granted: 1972-05-09
•
Expires: 1989-01-02
Abstract
Abstract UREA WITH A SMALL CONTENT OF BIURET AND WHICH DOES NOT CAKE ON STORAGE IS PRODUCED BY COATING GRANULATED UREA HAVING 0.9 TO 1.2% BY WEIGHT OF WATER, OBTAINED BY STARTING FROM A CONCENTRATED SOLUTION AT A TEMPERATURE BELOW 130*, WITH A FILM OF HEXAMETHYLENE TETRAMINE FORMED IN SITU BY REACTION OF 0 TO 50* C. BETWEEN A 32 TO 42% BY WEIGHT SOLUTION OF FORMOL (AQUEOUS FORMALDEHYDE), HAVING A PH OF 3 TO 6, ATOMIZED ONTO THE GRANULES AND EXCESS AMMONIA CONTENT IN SAID GRANULES AS THEY LEAVE THE GRANULATION STAGE.
Inventors
- 👤 Jean Cluzel
- 👤 Paul Souviron
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:24
CPC Classifications
C; C05; C05C; C05C9/00; C05C9/02; C07; C07C; C07C273/00; C07C273/02
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1975-05-09 | 1975-11-08 | 1976-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-09 | 1979-11-08 | 1980-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-09 | 1983-11-08 | 1984-05-09 | $7700.00 | Window Closed / Lapsed |