US3712879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Urea formaldehyde condensation products
Assignee: Individual
•
Filing: 1970-04-03
•
Granted: 1973-01-23
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Expires: 1990-04-03
Abstract
Abstract UREA FORMALDEHYDE CONDENSATION PRODUCTS, SUITABLE FOR USE AS LONG LASTING FERTILIZERS, ARE PRODUCED IN A TWO STAGE CONDENSATION PROCESS, THE FIRST STAGE BEING A PRECONDENSATION STAGE CARRIED OUT UNDER ALKALINE CONDITIONS, AND THE SECOND STAGE BEING A MAIN CONDENSATION, CARRIED OUT UNDER ACID CONDITIONS. INTERMEDIATE THE TWO STAGES, THE REACTION MEDIUM IS COOLED, AND THE PH IS ADJUSTED TO THAT DESIRED FOR THE SECOND STAGE. THE PRODUCT OF THE SECOND STAGE IS DRIED, FOR EXAMPLE IN SPRAY DRIER, RAPIDLY AND AT A LOW TEMPERATURE WHEREBY AN INCREASE IN INSOLUBLE NITROGEN IS AVOIDED.
Inventors
- 👤 J Strickrodt
- 👤 G Blume
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:06
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: 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) | 1976-01-23 | 1976-07-24 | 1977-01-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-23 | 1980-07-24 | 1981-01-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-23 | 1984-07-24 | 1985-01-23 | $7700.00 | Window Closed / Lapsed |