Patent US3699210A successfully refreshed from Google Patents.
US3699210A
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Method of graphitizing fibers
Assignee: Monsanto Research Corp
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Filing: 1968-09-06
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Granted: 1972-10-17
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Expires: 1988-09-06
Abstract
Abstract A method for carbonizing and/or graphitizing precursor fibers selected from the group consisting of polyacrylonitrile and aromatic polyamide fibers, wherein the fibers are pretreated with an oxygen-containing atmosphere at 180*-550*C. and thereafter heated in a laser beam in a non-oxidizing atmosphere at 700*1,200*C. for carbonizing and at 1,200*-3,600*C. for graphitizing.
Inventors
- 👤 Robert C Binning
- 👤 Leo P Parts
- 👤 Robert J Peresie
- 👤 Margaret L Rodenburg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:19
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/20; D01F9/21; D01F9/22; D01F9/24; D01F9/28; D01F9/30; D01F9/32; Y; Y10; Y10S; Y10S264/00; Y10S264/19
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
125 words
In a method for preparing a graphitized fiber from a precursor fiber as disclosed in claim 1 having the steps of a. pretreating the fiber by heating at a temperature of from 180* to 550*C. in an oxygen containing atmosphere for a time sufficient to blacken the fiber; and thereafter b. heating the blackened fiber in a non-oxidizing atmosphere at a temperature between 700*C. and about 1,200*C. to carbonize the fiber; the improvement further comprising the further step of irradiating at least once substantially all sides of the carbonized fiber with a CO2 laser beam in a non-oxidizing atmosphere at a temperature between about 1,200* and 3,600*C. for a period of time greater than one-tenth of a second, said time being dependent upon the temperature.
Claim 2
Dependent Claim
13 words
A method of claim 1 in which the precursor fiber is acrylonitrile polymer.
Claim 3
Dependent Claim
14 words
A method of claim 1 in which the precursor fiber is an aromatic polyamide.
Claim 4
Dependent Claim
13 words
A method of claim 2 in which the precursor fiber is acrylonitrile polymer.
Claim 5
Dependent Claim
14 words
A method of claim 2 in which the precursor fiber is an aromatic polyamide.
References Cited (Backward Citations)
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Cited
US3399252A
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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) | 1975-10-17 | 1976-04-17 | 1976-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-17 | 1980-04-17 | 1980-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-17 | 1984-04-17 | 1984-10-17 | $7700.00 | Window Closed / Lapsed |