Patent US2592809A successfully refreshed from Google Patents.
US2592809A
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Preparation of nitrogenous fertilizer compositions
Assignee: EIDP Inc
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Filing: 1949-01-27
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Granted: 1952-04-15
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Expires: 1969-01-27
Abstract
No abstract record available.
Inventors
- 👤 Robert D Kralovec
- 👤 Robert L Huffman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:51
CPC Classifications
C; C08; C08G; C08G12/00; C08G12/02; C08G12/04; C08G12/10; C08G12/12; C05; C05C; C05C9/00; C05C9/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
97 words
A METHOD FOR PREPARING A SOLID UREA-FORMALDEHYDE FERTILIZER COMPOSITION WHICH COMPRISES CONTINUOUSLY INTRODUCING A LIQUID AQUEOUS COMPOSITION CONTAINING FROM 1.3 TO 1.6 MOLECULAR EQUIVALENTS OF UREA PER MOLECULAR EQUIVALENT OF FORMALDEHYDE ONTO A MOVING SURFACE IN AN AMOUNT SUFFICIENT TO FORM A THIN LAYER ON SAID SURFACE OF FROM 1/32 INCH TO 1/4 INCH IN THICKNESS, SUBJECTING THE UREA-FORMALDEHYDE COMPOSITON TO REACTION THEREON AT A TEMPERATURE OF FROM 60* TO 120* C. AND AT A PH OF FROM 2 TO 6 UNTIL SOLIDIFICATION OF THE COMPOSITION OCCURS, AND THEREAFTER CONTINUOUSLY REMOVING THE SOLIDIFIED PRODUCT FROM SAID SURFACE.
Claim 2
Independent Claim
97 words
A METHOD FOR PREPARING A SOLID UREA-FORMALDEHYDE FERTILIZER COMPOSITION WHICH COMPRISES CONTINUOUSLY INTRODUCING A LIQUID AQUEOUS COMPOSITION CONTAINING FROM 1.3 TO 1.6 MOLECULAR EQUIVALENTS OF UREA PER MOLECULAR EQUIVALENT OF FORMALDEHYDE ONTO A MOVING SURFACE IN AN AMOUNT SUFFICIENT TO FORM A THIN LAYER ON SAID SURFACE OF FROM 1/32 INCH TO 1/4 INCH IN THICKNESS, SUBJECTING THE UREA-FORMALDEHYDE COMPOSITON TO REACTION THEREON AT A TEMPERATURE OF FROM 60* TO 120* C. AND AT A PH OF FROM 2 TO 6 UNTIL SOLIDIFICATION OF THE COMPOSITION OCCURS, AND THEREAFTER CONTINUOUSLY REMOVING THE SOLIDIFIED PRODUCT FROM SAID SURFACE.
References Cited (Backward Citations)
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Cited
US1929624A
Cited
US2034599A
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US2118439A
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US2456192A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-04-15 | 1955-10-15 | 1956-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-04-15 | 1959-10-15 | 1960-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-04-15 | 1963-10-15 | 1964-04-15 | $7700.00 | Window Closed / Lapsed |