Patent US2658892A successfully refreshed from Google Patents.
US2658892A
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US
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Preparation of melamine fkom
Assignee: —
•
Filing: —
•
Granted: 1953-11-10
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Expires: 1970-11-10
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:36
CPC Classifications
C; C07; C07D; C07D251/00; C07D251/02; C07D251/12; C07D251/26; C07D251/40; C07D251/54; C07D251/56; C07D251/60; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/77; C08G18/78; C08G18/7806; C08G18/7818; C08G18/7831
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
45 words
THE PROCESS OF PREPARING MELAMINE FROM BIURET WHICH CONSISTS OF HEATING BIURET AT A TEMPERATURE IN THE RANGE OF 300-350* C. IN A CLOSED VESSEL UNDER A PRESSURE OF AT LEAST 100 LBS. PER SQ. INCH, UNTIL MELAMINE IS FORMED AND RECOVERING THE SO-FORMED MELAMINE.
Claim 2
Dependent Claim
45 words
THE PROCESS OF PREPARING MELAMINE FROM BIURET WHICH CONSISTS OF HEATING BIURET AT A TEMPERATURE IN THE RANGE OF 300-350* C. IN A CLOSED VESSEL UNDER A PRESSURE OF AT LEAST 100 LBS. PER SQ. INCH, UNTIL MELAMINE IS FORMED AND RECOVERING THE SO-FORMED MELAMINE.
References Cited (Backward Citations)
US2550659A
Cited
GB598175A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-11-09 | 1957-05-11 | 1957-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-11-09 | 1961-05-11 | 1961-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-11-09 | 1965-05-11 | 1965-11-10 | $7700.00 | Window Closed / Lapsed |