Claims
- 1. A process for producing carbon fibers, comprising melt-spinning a mesophase pitch having a mesophase content of not less than about 70%, gas-phase nitrating the mesophase pitch fibers thus obtained in an oxygen-containing gas or inert gas atmosphere containing 0.1 to 50% by volume of NO.sub.2 at a temperature of from 60.degree. to 95.degree. C. for a period of not shorter than 4 hours to infusibilize the pitch fibers, and subjecting the infusibilized pitch fibers to carbonizing or to carbonizing and graphitizing to obtain carbon fibers having a tensile strength of not less than 370 kgf/mm.sup.2.
- 2. The process for producing carbon fibers as claimed in claim 1, wherein the mesophase pitch fibers are infusibilized in an oxygen-containing gas or inert gas atmosphere containing 1 to 10% by volume of NO.sub.2.
Priority Claims (1)
Number |
Date |
Country |
Kind |
5-057977 |
Feb 1993 |
JPX |
|
Parent Case Info
This application is a continuation of application Ser. No. 08/201,006, filed Feb. 24, 1994, now abandoned.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4788050 |
Hirose et al. |
Nov 1988 |
|
Foreign Referenced Citations (11)
Number |
Date |
Country |
1594982 |
May 1969 |
DEX |
3701631A1 |
Jul 1987 |
DEX |
47-33020 |
Aug 1972 |
JPX |
48-42696 |
Dec 1973 |
JPX |
49-118917 |
Nov 1974 |
JPX |
59-30915 |
Feb 1984 |
JPX |
60-259629 |
May 1984 |
JPX |
60-231825 |
Nov 1985 |
JPX |
61-502772 |
Nov 1986 |
JPX |
2-242919 |
Sep 1990 |
JPX |
4-24445 |
Apr 1992 |
JPX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
201006 |
Feb 1994 |
|