Patent US4014725A successfully refreshed from Google Patents.
US4014725A
Expired / Lapsed
US
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Method of making carbon cloth from pitch based fiber
Assignee: BP Corp North America Inc
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Filing: 1975-03-27
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Granted: 1977-03-29
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Expires: 1995-03-27
Abstract
Abstract Fibers having a high degree of flexibility and handleability are produced by oxidizing fibers spun from a carbonaceous pitch which has been transformed, in part, to a liquid crystal or so-called "mesophase" state to an oxygen content of from 17 per cent by weight to 30 per cent by weight. Because of their strength and handleability, these highly-oxidized fibers can be easily processed at high speeds by means of conventional yarn-transport systems, and readily woven or knit into cloth. Such cloth may then be heat treated to produce carbon or graphite cloth.
Inventors
- 👤 David Arthur Schulz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:46
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/145; D01F9/155; D01F9/15; Y; Y10; Y10S; Y10S264/00; Y10S264/19; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2918; Y10T442/00; Y10T442/30; Y10T442/3976; Y10T442/40
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
118 words
A process for producing carbon cloth which comprises spinning a carbonaceous fiber from a nonthixotropic carbonaceous pitch having a mesophase content of from 40 percent by weight to 90 percent by weight which under quiescent conditions forms a homogeneous bulk mesophase having large coalesced domains; heating the spun fiber in an oxygen-containing atmosphere at a temperature of from 250° to 500° C. for a time sufficient to oxidize the fiber to an oxygen content of from 17 percent by weight to 30 percent by weight; processing the oxidized fiber into a cloth by a process selected from this group consisting of knitting and weaving; and carbonizing the cloth produced in this manner by heating in an inert atmosphere.
Claim 2
Dependent Claim
118 words
A process for producing carbon cloth which comprises spinning a carbonaceous fiber from a nonthixotropic carbonaceous pitch having a mesophase content of from 40 percent by weight to 90 percent by weight which under quiescent conditions forms a homogeneous bulk mesophase having large coalesced domains; heating the spun fiber in an oxygen-containing atmosphere at a temperature of from 250° to 500° C. for a time sufficient to oxidize the fiber to an oxygen content of from 17 percent by weight to 30 percent by weight; processing the oxidized fiber into a cloth by a process selected from this group consisting of knitting and weaving; and carbonizing the cloth produced in this manner by heating in an inert atmosphere.
Claim 3
Dependent Claim
27 words
A process as in claim 1 wherein the carbonaceous fiber which is spun from the carbonaceous pitch has a diameter of from 6 microns to 14 microns.
Claim 4
Dependent Claim
27 words
A process as in claim 1 wherein the spun fiber is oxidized to an oxygen content of from 18 percent by weight to 22 percent by weight.
Claim 5
Dependent Claim
27 words
A process as in claim 1 wherein the carbonaceous fiber which is spun from the carbonaceous pitch has a diameter of from 6 microns to 14 microns.
Claim 6
Dependent Claim
31 words
A process as in claim 1 wherein the oxygen-containing atmosphere is air and the spun fiber is heated in said atmosphere at a temperature of from 275° C. to 390° C.
Claim 7
Dependent Claim
27 words
A process as in claim 5 wherein the carbonaceous fiber which is spun from the carbonaceous pitch has a diameter of from 6 microns to 14 microns.
Claim 8
Dependent Claim
27 words
A process as in claim 5 wherein the spun fiber is oxidized to an oxygen content of from 18 percent by weight to 22 percent by weight.
Claim 9
Dependent Claim
27 words
A process as in claim 7 wherein the carbonaceous fiber which is spun from the carbonaceous pitch has a diameter of from 6 microns to 14 microns.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-28 | 1980-09-27 | 1981-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-28 | 1984-09-27 | 1985-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-28 | 1988-09-27 | 1989-03-29 | $7700.00 | Window Closed / Lapsed |