Process for producing carbon fibers

摘要

Improved carbon fibers (including graphite fibers) are produced by drying acrylic fibers in a water-swollen state spun from an inorganic solvent solution of an acrylonitrile homopolymer or copolymer containing at least 85 mol % acrylonitrile and having an orientation degree of at least 50% and a water content of 5 to 150%. The drying step is carried out at a temperature below 70 DEG C to reduce the water content in said fibers to below 4%. The dried fibers are then heated to form the improved carbon fibers.