US2961710A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for making a foamed polyurethane filter
Assignee: Individual
•
Filing: 1957-01-04
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Granted: 1960-11-29
•
Expires: 1977-01-04
Abstract
No abstract record available.
Inventors
- 👤 Norman H Stark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:33
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/36; C08J9/40; C08J9/42; B; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/1669; B01D39/1676; C08J9/38; C08J2375/00; C08J2375/04; C08J2375/06; C08J2483/00; Y; Y10; Y10S; Y10S264/00; Y10S264/13; Y10S521/00; Y10S521/918; Y10S55/00; Y10S55/13
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
66 words
A METHOD OF MAKING AN OPEN CELLED POLYURETHANE FOAM FILTER FOR USE IN FILTERING A FLUID TO REMOVE SOLID PARTICLES ENTRAINED THEREIN, COMPRISING FORMING A POLYURETHANE PLASTIC FOAM, SOAKING SAID FORM IN A WEAKENING AGENT CAPABLE OF EXPANDING THE FOAM TO WEAKEN ITS CELL WALL STRUCTURE, AND VIOLENTLY AGITATING THE WEAKENED FOAM BY MECHANICALLY WORKING THE SAME THEREBY TO INCREASE THE NUMBER OF INTERCONNECTING CELLS THEREIN.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-11-29 | 1964-05-30 | 1964-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-11-29 | 1968-05-30 | 1968-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-11-29 | 1972-05-30 | 1972-11-29 | $7700.00 | Window Closed / Lapsed |