US4456521A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Three layer laminate
Assignee: Diamond Shamrock Chemicals Co
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Filing: 1983-04-19
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Granted: 1984-06-26
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Expires: 2003-04-19
Abstract
Abstract The disclosure is directed to preparing three-layer laminated electrodes suitable for use as oxygen (air) cathodes in chlor-alkali and other electrochemical cells, fuel cells and in other electrochemical applications. This three-layer laminate includes an active layer or sheet containing from about 60 to about 85 wt. % active carbon, the remainder being unsintered, fibrillated polytetrafluoroethylene in intimate admixture with said active carbon, said active layer laminated on its working surface to a current distributor and on its opposite surface to a porous, coherent, hydrophobic polytetrafluoroethylene-containing wetproofing layer.
Inventors
- 👤 Frank Solomon
- 👤 Charles Grun
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 00:11
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/86; H01M4/88; H01M4/8817; H01M4/8821; C; C25; C25B; C25B11/00; C25B11/04; C25B11/042; C25B11/043; H01M4/90; H01M4/92; H01M4/925; H01M4/926; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/50
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
74 words
In a laminated oxygen cathode comprising an active layer or sheet laminated on its working surface to a current distributor and on its opposite surface to a polytetrafluoroethylene-containing wetproofing layer, the improvement comprising said active layer or sheet being formed from a fibrillated mixture of unsintered polytetrafluoroethylene and active carbon particles surface area of at least about 1000 m 2 /g or more and a particle size of about 1 to about 30 microns.
Claim 2
Dependent Claim
74 words
In a laminated oxygen cathode comprising an active layer or sheet laminated on its working surface to a current distributor and on its opposite surface to a polytetrafluoroethylene-containing wetproofing layer, the improvement comprising said active layer or sheet being formed from a fibrillated mixture of unsintered polytetrafluoroethylene and active carbon particles surface area of at least about 1000 m 2 /g or more and a particle size of about 1 to about 30 microns.
Claim 3
Dependent Claim
16 words
An oxygen cathode as in claim 1 wherein said active carbon contains a precious metal catalyst.
Claim 4
Dependent Claim
13 words
An oxygen cathode as in claim 2 wherein said precious metal is platinum.
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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) | 1987-06-26 | 1987-12-26 | 1988-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-26 | 1991-12-26 | 1992-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-26 | 1995-12-26 | 1996-06-26 | $7700.00 | Window Closed / Lapsed |