Patent US3579369A successfully refreshed from Google Patents.
Patent US3054775A successfully refreshed from Google Patents.
US3054775A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymerization of formaldehyde by nickel-phosphine complexes
Assignee: Wyeth Holdings LLC
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Filing: 1961-02-24
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Granted: 1962-09-18
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Expires: 1981-02-24
Abstract
No abstract record available.
Inventors
- 👤 Hodes William
- 👤 Lewis S Meriwether
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:49
CPC Classifications
C; C08; C08G; C08G2/00; C08G2/06; C08G2/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
24 words
A PROCESS FOR POLYMERIZING FORMALDEHYDE COMPRISING CONTACTING SUBSTANTIALLY ANHYDROUS MONOMERIC FORMALDEHYDE WITH BIS(TRI-N-BUTYLPHOSPHINE) NICKEL DICHLORIDE AND RECOVERING A HIGH MOLECULAR WEIGHT POLYMER OF FORMALDEHYDE.
Claim 2
Dependent Claim
24 words
A PROCESS FOR POLYMERIZING FORMALDEHYDE COMPRISING CONTACTING SUBSTANTIALLY ANHYDROUS MONOMERIC FORMALDEHYDE WITH BIS(TRI-N-BUTYLPHOSPHINE) NICKEL DICHLORIDE AND RECOVERING A HIGH MOLECULAR WEIGHT POLYMER OF FORMALDEHYDE.
References Cited (Backward Citations)
US2828286A
Cited
US2734889A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-09-17 | 1966-03-19 | 1966-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-09-17 | 1970-03-19 | 1970-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-09-17 | 1974-03-19 | 1974-09-18 | $7700.00 | Window Closed / Lapsed |