US3634035A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Continuous production of uniform graphite fibers
Assignee: Celanese Corp
•
Filing: 1969-04-28
•
Granted: 1972-01-11
•
Expires: 1989-04-28
Abstract
Abstract A rapid continuous process is provided for the conversion of a predominantly amorphous carbonaceous fibrous material containing at least 75 percent carbon by weight (preferably at least 90 percent carbon by weight) to a uniform fibrous material of predominantly graphitic carbon. The carbonaceous fibrous material is passed through a reducing flame which imparts a minimum fiber temperature of at least 1,900* C. while the fibrous material is under tension at least sufficient to prevent visible sagging. In a preferred embodiment of the invention, the reducing flame is generated by a fuel-oxidant mixture, e.g. an acetylene and oxygen mixture. Long lengths of graphite yarns having substantially uniform properties, e.g. graphitic composition, Young''s modulus, and tenacity, may be produced through the use of the present process.
Inventors
- 👤 Dagobert E Stuetz
- 👤 Leo R Belohlav
- 👤 Arthur M Reader
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:30
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/20; D01F9/24; D01F9/21; D01F9/22; G; G01; G01B; G01B21/00; G01B21/02; G01B21/04; G01B21/047
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
12 words
A continuous process according to claim 1 wherein said oxidant is oxygen.
Claim 2
Dependent Claim
12 words
A continuous process according to claim 1 wherein said fuel is acetylene.
Claim 3
Dependent Claim
12 words
A continuous process according to claim 2 wherein said fuel is propane.
Claim 4
Dependent Claim
20 words
A continuous process according to claim 1 wherein said carbonaceous fibrous material has been derived from a cellulosic fibrous material.
Claim 5
Dependent Claim
20 words
A continuous process according to claim 1 wherein said carbonaceous fibrous material has been derived from a polybenzimidazole fibrous material.
Claim 6
Dependent Claim
26 words
A continuous process according to claim 1 wherein said carbonaceous fibrous material has been derived from an acrylic fibrous material consisting primarily of recurring acrylonitrile units.
Claim 7
Dependent Claim
19 words
A continuous process according to claim 7 wherein said carbonaceous fibrous material has been derived from an acrylonitrile homopolymer.
Claim 8
Dependent Claim
27 words
A continuous process according to claim 1 wherein the residence time of said carbonaceous fibrous material in said reducing flame is from about 6 to 17 seconds.
Claim 9
Dependent Claim
17 words
A continuous process according to claim 4 wherein an inert atmosphere is provided around said reducing flame.
Claim 10
Dependent Claim
15 words
A continuous process according to claim 1 wherein said carbonaceous fibrous material is a yarn.
Claim 11
Dependent Claim
123 words
A continuous process for producing a predominantly graphitic fibrous material comprising continuously passing a carbonaceous fibrous material having: a. at least 90 percent of its weight attributable to carbon, b. a relatively amorphous X-ray diffraction pattern, and c. structural integrity for at least two seconds at a fiber temperature of 1,900* C., through the luminous portion of a reducing flame generated by an acetylene-oxygen mixture imparting to said fibrous material a minimum temperature of at least 1,900* C. in which the ratio of oxygen to acetylene is less than the stoichiometric amount required to completely oxidize the acetylene for a residence time of about 2 to 24 seconds while said fibrous material is under a tension at least sufficient to prevent visible sagging.
Claim 12
Dependent Claim
20 words
A continuous process according to claim 12 wherein said carbonaceous fibrous material has been derived from a cellulosic fibrous material.
Claim 13
Dependent Claim
20 words
A continuous process according to claim 12 wherein said carbonaceous fibrous material has been derived from a polybenzimidazole fibrous material.
Claim 14
Dependent Claim
26 words
A continuous process according to claim 12 wherein said carbonaceous fibrous material has been derived from an acrylic fibrous material consisting primarily of recurring acrylonitrile units.
Claim 15
Dependent Claim
19 words
A continuous process according to claim 15 wherein said carbonaceous fibrous material has been derived from an acrylonitrile homopolymer.
Claim 16
Dependent Claim
26 words
A continuous process according to claim 12 wherein the residence time of said carbonaceous fibrous material in said reducing flame is about 6 to 17 seconds.
Claim 17
Dependent Claim
15 words
A continuous process according to claim 12 wherein said carbonaceous fibrous material is a yarn.
References Cited (Backward Citations)
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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) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |