PURPOSE: To prevent occurrence of staining on the peripheries of discharge holes of a spinneret, by melting a polyester polymer containing titanium oxide to give an apparent viscosity of a specific value or above and discharging the resultant melt through a spinneret electrically insulated from the adjacent members.
CONSTITUTION: A polyester polymer, e.g. polybutylene terephthalate, containing titanium oxide is melt spun. In the process, a spinneret is electrically insulated from the adjacent members thereof and the apparent viscosity of the melt in passing through discharge holes of the spinneret is adjusted to ≥500 P, preferably 600W3,000 P. The spinneret 1 is electrically insulated by providing seals 3 and 3' consisting of an insulator on and under the spinneret 1.
TSUKAMOTO TETSUO
SATO YOSHIAKI
