| abstract |
A method for producing a polyacrylonitrile fiber comprising a spinning step, a pre-stretching step, a drying step, and a post-stretching step including a dry heat drawing step of any one of the following (a) to (c): (a) Extending | stretching in air at room temperature from the thread separation point on a hot roll to the first tanning point on a next roll, 130 degreeC or more; (b) extending the distance from the yarn separation point on the hot roll to the first tanning point on the next roll to 20 cm or less; (c) Post-stretching is performed in a hot plate stretching zone in which a hot plate is disposed between two rolls, and one of the two rolls disposed in front of the hot plate stretching zone is a preheating hot roll, and the starting point of the fitting between the hot plate and the yarn is The hot plate is positioned so as to have a distance of 30 cm or less from the yarn separation point on the preheating hot roll, and stretching is performed at a surface speed of the preheating hot roll at 100 m / min or more. |