US2670305A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making filter material
Assignee: Willson Products Inc
•
Filing: 1951-03-26
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Granted: 1954-02-23
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Expires: 1971-03-26
Abstract
No abstract record available.
Inventors
- 👤 William J Wiswesser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:58
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
123 words
THE METHOD OF TREATING FELT TO CONSIDERABLY INCREASE ITS AIR FILTERING QUALITY, COMPRISING FORMING THE FELT INTO A PLURALITY OF SMALL SHEETS OF LENGTH APROXIMATING THE WIDTH THEREOF, IMPREGNATING THE SHEETS WITH A SOLUTION OF ORGANIC SOLVENT AND A RESIN WHICH BECOMES FRANGIBLE WHEN DRIED, SPINNING SAID SHEETS AT HIGH SPEED AND THEREBY REMOVING MOST OF THE RESIN SOLUTION BY CENTRIFUGAL FORCE AND SUBJECTING SAID SHEETS TO A DRYING ATMOSPHERE TO EFFECT DRYING THEREOF, AGITATING AND CONTINUOUSLY BEATING SAID DRIED SHEETS WHILE IN LOOSE, CRUMPLED CONDITION UNTIL THE RESIN CONTAINED THEREIN IS FINELY DIVIDED INTO EXCEEDINGLY SMALL PARTICLES THAT BECOME LODGED IN THE INTERSTICES AND CONSIDERABLY INCREASE THE AIR FILTERING EFFICIENCY, AND FINALLY CUTTING SAID SHEETS INTO SIZES AND SHAPES DESIRED AS FILTERS.
Claim 2
Independent Claim
123 words
THE METHOD OF TREATING FELT TO CONSIDERABLY INCREASE ITS AIR FILTERING QUALITY, COMPRISING FORMING THE FELT INTO A PLURALITY OF SMALL SHEETS OF LENGTH APROXIMATING THE WIDTH THEREOF, IMPREGNATING THE SHEETS WITH A SOLUTION OF ORGANIC SOLVENT AND A RESIN WHICH BECOMES FRANGIBLE WHEN DRIED, SPINNING SAID SHEETS AT HIGH SPEED AND THEREBY REMOVING MOST OF THE RESIN SOLUTION BY CENTRIFUGAL FORCE AND SUBJECTING SAID SHEETS TO A DRYING ATMOSPHERE TO EFFECT DRYING THEREOF, AGITATING AND CONTINUOUSLY BEATING SAID DRIED SHEETS WHILE IN LOOSE, CRUMPLED CONDITION UNTIL THE RESIN CONTAINED THEREIN IS FINELY DIVIDED INTO EXCEEDINGLY SMALL PARTICLES THAT BECOME LODGED IN THE INTERSTICES AND CONSIDERABLY INCREASE THE AIR FILTERING EFFICIENCY, AND FINALLY CUTTING SAID SHEETS INTO SIZES AND SHAPES DESIRED AS FILTERS.
References Cited (Backward Citations)
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Cited
US1612585A
Cited
US2196256A
Cited
US2366853A
Cited
US2385300A
Cited
US2514145A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-02-22 | 1957-08-24 | 1958-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-02-22 | 1961-08-24 | 1962-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-02-22 | 1965-08-24 | 1966-02-23 | $7700.00 | Window Closed / Lapsed |