US4032430A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing carbon fibers from mesophase pitch
Assignee: BP Corp North America Inc
•
Filing: 1973-12-11
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Granted: 1977-06-28
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Expires: 1993-12-11
Abstract
Abstract An improved process for producing pitch which has been transformed, in part, to a liquid crystal or so-called "mesophase" state. According to the process, pitch of a given mesophase content, suitable for producing carbon fibers, is produced in substantially shorter periods of time than heretofore possible, at a given temperature, by subjecting the pitch to reduced pressure during formation of the mesophase.
Inventors
- 👤 Irwin Charles Lewis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:17
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/32; D01F9/322; C; C10; C10C; C10C3/00; C10C3/002; D01F9/145; Y; Y10; Y10S; Y10S264/00; Y10S264/19
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
61 words
A process for producing a mesophase pitch which comprises heating a carbonaceous pitch at a temperature of from 350° C. to 450° C. for a time sufficient to produce a mesophase content of from 40 percent by weight to 90 percent by weight while subjecting the pitch to a pressure of less than 100 millimeters Hg during formation of the mesophase.
Claim 2
Dependent Claim
61 words
A process for producing a mesophase pitch which comprises heating a carbonaceous pitch at a temperature of from 350° C. to 450° C. for a time sufficient to produce a mesophase content of from 40 percent by weight to 90 percent by weight while subjecting the pitch to a pressure of less than 100 millimeters Hg during formation of the mesophase.
Claim 3
Dependent Claim
41 words
A process as in claim 1 wherein the pitch is heated at a temperature of from 380° C. to 440° C. for a time sufficient to produce a mesophase content of from 50 percent by weight to 65 percent by weight.
Claim 4
Dependent Claim
20 words
A process as in claim 2 wherein the pitch is subjected to a pressure of less than 30 millimeters Hg.
References Cited (Backward Citations)
US3035308A
Cited
US3040005A
Cited
US3355377A
Cited
US3552922A
Cited
US3490586A
Cited
US3558276A
Cited
US3595946A
Cited
US3718493A
Cited
US3634220A
Cited
US3767741A
Cited
US3761387A
Cited
US3787541A
Cited
US3799865A
Cited
US3814566A
Cited
US3919376A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-06-27 | 1980-12-27 | 1981-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-27 | 1984-12-27 | 1985-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-27 | 1988-12-27 | 1989-06-28 | $7700.00 | Window Closed / Lapsed |