| 摘要 |
<p>Conventional types of polyimide fibers have such disadvantages that the polyimide fibers have poor hydrolysis resistance and have high thermal shrinkage coefficients at higher temperatures. Disclosed are polyimide fibers characterized by having a breaking elongation of 10 to 100% inclusive, a breaking strength of 1.0 to 8.0 cN/dtex inclusive, a fiber fineness of 0.5 to 20 dtex inclusive, a breaking strength retention rate of 80% or more after treated under the conditions of 150°C/100%RH/48 hours, a thermal shrinkage coefficient of 3.0% or less at 300°C, an ellipsoidal cross-sectional view having an ellipticity of 1.1 or more or an array-shaped cross-sectional view. Also disclosed is a process for producing the polyimide fibers. When the polyimide fiber production process is employed, it becomes possible to produce polyimide fibers having excellent hydrolysis resistance and a small thermal shrinkage coefficient at a higher temperature.</p> |
