Patent JPS63243271A successfully refreshed from Google Patents.
Patent EP0245035A2 successfully refreshed from Google Patents.
EP0245035A2
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EP
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High modulus pitch-based carbon fiber and method for preparing same
Assignee: Tonen General Sekiyu KK
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Filing: 1987-04-30
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Granted: —
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Expires: 2007-04-30
Abstract
Abstract Extremely high modulus carbon fibers can be produced by carbonization at a substantially lower temperature, for example, at about 2500 DEG C. This is made possible by selectively stabilizing only an outer surface layer portion of a carbonaceous pitch-based fiber comprised mainly of optically anisotropic components, while retaining the inner portion of the fiber in a non-stabilized state and without damage to the crystallinity thereof.
Inventors
- 👤 Takashi Hino
- 👤 Tsutomu Naito
- 👤 Hiroyuki Kuroda
- 👤 Eiki Tsushima
- 👤 Tomio Nomura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 18:06
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/145
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
38 words
A pitch-based carbon fiber characterized in that the fiber comprises an inner portion and an outer layer portion thereof and the inner portion of the fiber has a substantially higher crystallinity than that of the outer layer portion.
Claim 2
Dependent Claim
38 words
A pitch-based carbon fiber characterized in that the fiber comprises an inner portion and an outer layer portion thereof and the inner portion of the fiber has a substantially higher crystallinity than that of the outer layer portion.
Claim 3
Dependent Claim
29 words
A carbon fiber according to claim 1, wherein the inner portion of the fiber has a crystallite size at least 10% larger than that of the outer layer portion.
Claim 4
Dependent Claim
22 words
A carbon fiber according to claim 1 or claim 2, wherein the fiber has a Young's modulus of 700 GPa or more.
Claim 5
Dependent Claim
57 words
A method for preparing a pitch-based carbon fiber as claimed in claim 1, characterized by spinning a carbonaceous pitch composed mainly of optically anisotropic components to form a carbonaceous pitch fiber, selectively stabilizing an outer layer portion of the carbonaceous pitch fiber by oxidation, and then carbonizing the selectively-stabilized carbonaceous pitch fiber to produce a carbon fiber.
Claim 6
Dependent Claim
24 words
A method according to claim 4, wherein said carbonization is conducted at a temperature in a range of from 2000 0 C to 3000°C.
Claim 7
Dependent Claim
22 words
A method according to claim 5, wherein said carbonization is conducted at a temperature in a range of from 2000°C to 2600°C.
Claim 8
Independent Claim
34 words
A method according to any one of claims 4 to 6, wherein said carbonaceous pitch comprises more than 90% of optically anisotropic components and said pitch has a softening point of 230 to 320°C.
Claim 9
Dependent Claim
18 words
A method according to claim 7, wherein said carbonaceous pitch comprises more than 97% of optically anisotropic components.
Claim 10
Dependent Claim
18 words
A method according to claim 8, wherein said carbonaceous pitch comprises more than 99% of optically anisotropic components.
Claim 11
Independent Claim
23 words
A method according to any one of claims 4 to 9, wherein said spinning is conducted at a temperature of 280 to 370°C.
Claim 12
Independent Claim
56 words
A method according to any one of claims 7 to 9, wherein said pitch fiber has a diameter of 5 to 20 µm and said stabilization is conducted in air under conditions of a starting temperature of 150 to 200°C, a temperature elevation rate of 1 to 2°C/min and a final temperature of 250 to 350°C.
Claim 13
Dependent Claim
17 words
A method according to claim 11, wherein said fiber has a diameter of 9 to 14 µm.
References Cited (Backward Citations)
No citation records indexed.
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