Patent US4405544A successfully refreshed from Google Patents.
US4405544A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Strengthening of carbon black-teflon-containing electrode
Assignee: Diamond Shamrock Chemicals Co
•
Filing: 1982-02-16
•
Granted: 1983-09-20
•
Expires: 2002-02-16
Abstract
Abstract This disclosure is directed to strengthening carbon-black particulate "Teflon" (PTFE) mixes destined to be formed into active layers in air cathodes, which comprises mixing an aqueous dispersion of particulate polytetrafluoroethylene with an aqueous suspension of particulate carbon-black; washing and drying; mixing with a pore-forming agent; fibrillating said mixtures; washing and drying; adding polytetrafluoroethylene fibers while chopping said dried fibrillated mixture and thereafter forming said chopped mixture into a sheet, which was washed and dried.
Inventors
- 👤 Frank Solomon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:18
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/86; H01M4/88; H01M4/8875; C; C25; C25B; C25B11/00; C25B11/04; C25B11/042; C25B11/043; H01M4/96; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/50
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
59 words
A method for preparing an electrode active layer comprising mixing an aqueous dispersion of particulate polytetrafluoroethylene with an aqueous suspension of particulate carbon black; washing and drying; mixing with a pore-forming agent; fibrillating said mixture; drying; adding polytetrafluoroethylene fibers while chopping said dried fibrillated mixture and thereafter forming said chopped mixture into a sheet, which was washed and dried.
Claim 2
Independent Claim
59 words
A method for preparing an electrode active layer comprising mixing an aqueous dispersion of particulate polytetrafluoroethylene with an aqueous suspension of particulate carbon black; washing and drying; mixing with a pore-forming agent; fibrillating said mixture; drying; adding polytetrafluoroethylene fibers while chopping said dried fibrillated mixture and thereafter forming said chopped mixture into a sheet, which was washed and dried.
Claim 3
Dependent Claim
15 words
A method as in claim 1 which includes chopping said particulate mix prior to fibrillating.
Claim 4
Dependent Claim
38 words
A method as in claim 1 wherein said polytetrafluoroethylene fibers prior to chopping are characterized by an average length of from about 0.005 to about 0.05 inch and a denier (per filament) of about 3 to about 10.
References Cited (Backward Citations)
US3409472A
Cited
GB1237934A
Cited
GB1284054A
Cited
US3935029A
Cited
US3890417A
Cited
US4150076A
Cited
US4058482A
Cited
US4153661A
Cited
US4170540A
Cited
US4289600A
Cited
US4187350A
Cited
US4352768A
Cited
US4299682A
Cited
US4317789A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-09-19 | 1987-03-21 | 1987-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-19 | 1991-03-21 | 1991-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-19 | 1995-03-21 | 1995-09-20 | $7700.00 | Window Closed / Lapsed |