Patent US4064207A successfully refreshed from Google Patents.
US4064207A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fibrillar carbon fuel cell electrode substrates and method of manufacture
Assignee: RTX Corp
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Filing: 1976-02-02
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Granted: 1977-12-20
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Expires: 1996-02-02
Abstract
Abstract Porous carbon sheets suitable for use as fuel cell electrode support plates are produced from inexpensive carbonizable filaments. The filaments are chopped into short lengths, felted, sprayed with a binder and the binder is cured whereby sheets are defined. The sheets are thereafter pyrolyzed to convert both the binder and filaments to carbon and to thereby produce the desired porous substrate material.
Inventors
- 👤 Michael A. DeCrescente
- 👤 George K. Layden
- 👤 Roscoe A. Pike
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:43
CPC Classifications
D; D21; D21H; D21H5/00; D21H5/12; C; C04; C04B; C04B35/00; C04B35/71; C04B35/78; C04B35/80; C04B35/83; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/20; D01F9/21; D01F9/22; D21H13/00; D21H13/10; H; H01; H01M; H01M4/00; H01M4/86; H01M4/96; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/50; Y10; Y10T; Y10T428/00; Y10T428/30; Y10T442/00; Y10T442/50; Y10T442/56
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
190 words
A process for the manufacture of carbon substrate material having a fibrillar microstructure and a porosity in the range of 70-90% comprising the steps of: selecting an acrylic polymer filament having a diameter commensurate with the desired porosity of the substrate material, said filament containing at least 50% acrylonitrile; stabilizing a plurality of the selected acrylic polymer filaments by heating the filaments in an oxidizing atmosphere until between 3% and 15% by weight oxygen is introduced into the polymer; reducing the stabilized filaments to fibers having a preselected average length; felting the fibers of preselected average length to produce a layer of uniform thickness with random fiber orientation; impregnating the felted fibers with a resinous binder to define a sheet material, the binder comprising 12-25% by weight of the sheet material; subjecting the sheet material including the stabilized acrylic polymer fibers to an elevated temperature to cure the resinous binder; and subjecting the sheet material to a temperature in the range of 1000° C to 1260° C in a non-oxidizing atmosphere subsequent to curing the binder to pyrolyze the fibers and binder and thereby produce a porous carbon substrate material.
Claim 2
Dependent Claim
190 words
A process for the manufacture of carbon substrate material having a fibrillar microstructure and a porosity in the range of 70-90% comprising the steps of: selecting an acrylic polymer filament having a diameter commensurate with the desired porosity of the substrate material, said filament containing at least 50% acrylonitrile; stabilizing a plurality of the selected acrylic polymer filaments by heating the filaments in an oxidizing atmosphere until between 3% and 15% by weight oxygen is introduced into the polymer; reducing the stabilized filaments to fibers having a preselected average length; felting the fibers of preselected average length to produce a layer of uniform thickness with random fiber orientation; impregnating the felted fibers with a resinous binder to define a sheet material, the binder comprising 12-25% by weight of the sheet material; subjecting the sheet material including the stabilized acrylic polymer fibers to an elevated temperature to cure the resinous binder; and subjecting the sheet material to a temperature in the range of 1000° C to 1260° C in a non-oxidizing atmosphere subsequent to curing the binder to pyrolyze the fibers and binder and thereby produce a porous carbon substrate material.
Claim 3
Dependent Claim
35 words
The method of claim 1 wherein the step of reducing the selected filament to fibers comprises: mechanically severing the filamentary material so as to produce fibers having an aspect ratio commensurate with the desired porosity.
Claim 4
Dependent Claim
36 words
The method of claim 1 wherein the step of felting comprises: forming an aqueous slurry of the fibers; and depositing the fibers from the slurry on a substrate to define a felt; and drying the felt.
Claim 5
Dependent Claim
32 words
The method of claim 1 wherein the step of impregnating the felted fiber with a resinous binder comprises: spraying the felted fibers with a resin while applying suction to the felted fibers.
Claim 6
Dependent Claim
32 words
The method of claim 2 wherein the step of impregnating the felted fiber with a resinous binder comprises: spraying the felted fibers with a resin while applying suction to the felted fibers.
Claim 7
Dependent Claim
35 words
The method of claim 3 wherein the step of reducing the selected filament to fibers comprises: mechanically severing the filamentary material so as to produce fibers having an aspect ratio commensurate with the desired porosity.
Claim 8
Dependent Claim
36 words
The method of claim 5 wherein the step of felting comprises: forming an aqueous slurry of the fibers; and depositing the fibers from the slurry on a substrate to define a felt; and drying the 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) | 1980-12-19 | 1981-06-20 | 1981-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-19 | 1985-06-20 | 1985-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-19 | 1989-06-20 | 1989-12-20 | $7700.00 | Window Closed / Lapsed |