US3028433A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for improving polypropylene glycols
Assignee: Union Carbide Corp
•
Filing: 1959-09-09
•
Granted: 1962-04-03
•
Expires: 1979-09-09
Abstract
No abstract record available.
Inventors
- 👤 Donald G Leis
- 👤 Robert J Knopf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:37
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/48; C08G18/4825
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1536544A
Cited
US2915496A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-04-02 | 1965-10-02 | 1966-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-04-02 | 1969-10-02 | 1970-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-04-02 | 1973-10-02 | 1974-04-03 | $7700.00 | Window Closed / Lapsed |