US2498206A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of paraformaldehyde
Assignee: Cities Service Oil Co
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Filing: 1948-12-07
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Granted: 1950-02-21
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Expires: 1968-12-07
Abstract
No abstract record available.
Inventors
- 👤 Bertrand W Greenwald
- 👤 Raymond K Cohen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:14
CPC Classifications
C; C08; C08G; C08G2/00; C08G2/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
95 words
THE PROCESS FOR PRODUCING PARAFORMALDEHYDE, INCLUDING SUBJECTING A FORMALDEHYDE SOLUTION TO A FIRST STAGE CONCENTRATION, INTERRUPTING THE CONCENTRATION WHEN THE CONCENTRATE CONTAINS FROM ABOUT 55 TO ABOUT 65 PER CENT FORMULADEHYDE BY WEIGHT, HOLDING THE CONCENTRATE AT A TEMPERATURE EXPRESSED IN *C. VARYING FROM THE NUMERICAL VALUE OF THE FORMALDEHYDE CONCENTRATION BY NOT MORE THAN 7 FOR A PERIOD OF TIME SUFFICIENT TO ALLOW SUBSTANTIAL POLYMERIZATION OF FORMALDEHYDE, AND THEREAFTER SUBJECTING THE CONCENTRATE TO A SECOND STAGE CONCENTRATION AND DRYING UNTIL A PARAFORMALDEHYDE ASSAYING NOT LESS THAN 95 PER CENT FORMALDEHYDE BY WEIGHT IS PRODUCED.
Claim 2
Dependent Claim
95 words
THE PROCESS FOR PRODUCING PARAFORMALDEHYDE, INCLUDING SUBJECTING A FORMALDEHYDE SOLUTION TO A FIRST STAGE CONCENTRATION, INTERRUPTING THE CONCENTRATION WHEN THE CONCENTRATE CONTAINS FROM ABOUT 55 TO ABOUT 65 PER CENT FORMULADEHYDE BY WEIGHT, HOLDING THE CONCENTRATE AT A TEMPERATURE EXPRESSED IN *C. VARYING FROM THE NUMERICAL VALUE OF THE FORMALDEHYDE CONCENTRATION BY NOT MORE THAN 7 FOR A PERIOD OF TIME SUFFICIENT TO ALLOW SUBSTANTIAL POLYMERIZATION OF FORMALDEHYDE, AND THEREAFTER SUBJECTING THE CONCENTRATE TO A SECOND STAGE CONCENTRATION AND DRYING UNTIL A PARAFORMALDEHYDE ASSAYING NOT LESS THAN 95 PER CENT FORMALDEHYDE BY WEIGHT IS PRODUCED.
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) | 1953-02-20 | 1953-08-22 | 1954-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-02-20 | 1957-08-22 | 1958-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-02-20 | 1961-08-22 | 1962-02-21 | $7700.00 | Window Closed / Lapsed |