US2575497A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sheetsxsheet i
Assignee: —
•
Filing: —
•
Granted: 1951-11-20
•
Expires: 1968-11-20
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:18
CPC Classifications
C; C07; C07D; C07D251/00; C07D251/02; C07D251/12; C07D251/26; C07D251/40; C07D251/54; C07D251/56; C07D251/60; C07D251/58; Y; Y10; Y10S; Y10S159/00; Y10S159/15
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
57 words
IN THE PROCESS OF MAKING MELAMINE COMPRISING CONTINUOUSLY PASSING A MELAMINE-FORMING SUBSTANCE THROUGH A REACTION ZONE IN A TUBE MAINTAINED AT A TEMPERATURE WITHIN THE APPROXIMATE RANGE OF 350*-600* C., AND UNDER A PRESSURE OF AT LEAST 100 P. S. I., THE IMPROVEMENT WHICH COMPRISES PASSING SAID MELAMINE-FORMING SUBSTANCE THROUGH A TUBE WHOSE INNER SURFACE IS GRAPHITE.
Claim 2
Dependent Claim
57 words
IN THE PROCESS OF MAKING MELAMINE COMPRISING CONTINUOUSLY PASSING A MELAMINE-FORMING SUBSTANCE THROUGH A REACTION ZONE IN A TUBE MAINTAINED AT A TEMPERATURE WITHIN THE APPROXIMATE RANGE OF 350*-600* C., AND UNDER A PRESSURE OF AT LEAST 100 P. S. I., THE IMPROVEMENT WHICH COMPRISES PASSING SAID MELAMINE-FORMING SUBSTANCE THROUGH A TUBE WHOSE INNER SURFACE IS GRAPHITE.
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) | 1954-11-19 | 1955-05-21 | 1955-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-11-19 | 1959-05-21 | 1959-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-11-19 | 1963-05-21 | 1963-11-20 | $7700.00 | Window Closed / Lapsed |