Patent US2793398A successfully refreshed from Google Patents.
US2793398A
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Preparation of urea in granular form
Assignee: Stamicarbon BV
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Filing: 1955-08-30
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Granted: 1957-05-28
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Expires: 1975-08-30
Abstract
No abstract record available.
Inventors
- 👤 Hallie Gerardus
- 👤 Johan W Hoogendonk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:13
CPC Classifications
B; B01; B01J; B01J2/00; B01J2/02; B01J2/06; C; C07; C07C; C07C273/00; C07C273/02; C07C273/14; C07C273/16; Y; Y10; Y10S; Y10S425/00; Y10S425/101
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
104 words
IN THE METHOD OF PREPARING UREA IN GRANULAR FORM BY CAUSING A MEMBER OF THE GROUP CONSISTING OF HIGHLY CONCENTRATED AQUEOUS UREA SOLUTION AND MOLTEN UERA IN THE FORM OF DROPS TO FALL THROUGH A COLUMN OF THIN MINERAL OIL AT A TEMPERATURE BELOW TH SOLIDIFICATION POINT OF THE UREA DROPS, THE IMPROVEMENT WHICH COMPRISES ADDING TO THE SAID MINERAL OIL AT LEAST 15% BY WEIGHT OF A WAX, SAID WAX BEING CAPABLE OF FORMING AN UNCTUOUS MASS AT 25*C. BUT BEING A COMPLETELY HOMOGENEOUS HIGHLY FLUID LIQUID AT 75*C. AND THEREAFTER CENTRIFUGING THE UREA UNTIL THE OIL CONTENT IS LESS THAN ABOUT 2.4%.
Claim 2
Dependent Claim
104 words
IN THE METHOD OF PREPARING UREA IN GRANULAR FORM BY CAUSING A MEMBER OF THE GROUP CONSISTING OF HIGHLY CONCENTRATED AQUEOUS UREA SOLUTION AND MOLTEN UERA IN THE FORM OF DROPS TO FALL THROUGH A COLUMN OF THIN MINERAL OIL AT A TEMPERATURE BELOW TH SOLIDIFICATION POINT OF THE UREA DROPS, THE IMPROVEMENT WHICH COMPRISES ADDING TO THE SAID MINERAL OIL AT LEAST 15% BY WEIGHT OF A WAX, SAID WAX BEING CAPABLE OF FORMING AN UNCTUOUS MASS AT 25*C. BUT BEING A COMPLETELY HOMOGENEOUS HIGHLY FLUID LIQUID AT 75*C. AND THEREAFTER CENTRIFUGING THE UREA UNTIL THE OIL CONTENT IS LESS THAN ABOUT 2.4%.
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) | 1960-05-27 | 1960-11-26 | 1961-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-05-27 | 1964-11-26 | 1965-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-05-27 | 1968-11-26 | 1969-05-28 | $7700.00 | Window Closed / Lapsed |