Patent US3806474A successfully refreshed from Google Patents.
US3806474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydrophilic polyester urethane foam
Assignee: Princeton Polymer Sponge Corp
•
Filing: 1972-12-27
•
Granted: 1974-04-23
•
Expires: 1992-12-27
Abstract
Abstract A SPONGE IS MADE OF A POLYESTER POLYURETHANE HAVING A DENSITY OF 3 TO 4.5LB./CU.FT., A VOLUME SWELL IN WATER OF 2-50% AND A CELL SIZE OF 100 TO 5 CELLS PER LINEAR INCH. THE SPONGE IS PREPARED USING THREE DIFFERENT SURFACTANTS AND HAS AN OPEN CELL STRUCTURE.
Inventors
- 👤 E Blair
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:50
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/0061; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/10; C08G18/28; C08G18/40; C08G18/42; C08G18/4244; C08G18/4247; C08G18/425; C08J9/0014; C08K; C08K5/00; C08K5/04; C08K5/10; C08K5/11; C08L; C08L75/00; C08L75/04; C08L75/06; C08L91/00; C08G2110/00; C08G2110/0008; C08G2110/0041; C08G2110/005; C08G2110/0058; C08J2375/00; C08J2375/04; C08J2375/06; C08J2471/00; Y; Y10; Y10S; Y10S521/00; Y10S521/905
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1977-04-22 | 1977-10-22 | 1978-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-22 | 1981-10-22 | 1982-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-22 | 1985-10-22 | 1986-04-23 | $7700.00 | Window Closed / Lapsed |