Patent US1539577A successfully refreshed from Google Patents.
US5368734A
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Triboelectric filtration material
Assignee: W.L. Gore and Associates Inc
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Filing: 1993-12-20
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Granted: 1994-11-29
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Expires: 2013-12-20
Abstract
Abstract An electrically charged air filter which comprises a blend of clean expanded porous polytetrafluoroethylene fibers and clean polyamide fibers.
Inventors
- 👤 Ray Wnenchak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:03
CPC Classifications
B; B03; B03C; B03C3/00; B03C3/28; B03C3/30; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/1607; B01D39/1623; Y; Y10; Y10T; Y10T442/00; Y10T442/50; Y10T442/56; Y10T442/60; Y10T442/608; Y10T442/609; Y10T442/613; Y10T442/627; Y10T442/635
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
18 words
A electrically charged filter which comprises a blend of clean expanded pourous polytetrafluoroethylene fibers and clean polyamide fibers.
Claim 2
Dependent Claim
18 words
A electrically charged filter which comprises a blend of clean expanded pourous polytetrafluoroethylene fibers and clean polyamide fibers.
Claim 3
Dependent Claim
11 words
The filter of claim 1 wherein the polyamide fibers are crimped.
Claim 4
Dependent Claim
13 words
The filter of claim 1 or 2 wherein the polyamide is nylon 66.
Claim 5
Dependent Claim
12 words
The filter of claim 3 in the form of a carded batt.
Claim 6
Dependent Claim
11 words
The filter of claim 3 in the form of a felt.
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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) | 1997-11-28 | 1998-05-30 | 1998-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-11-28 | 2002-05-30 | 2002-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-11-28 | 2006-05-30 | 2006-11-29 | $7700.00 | Window Closed / Lapsed |