PURPOSE: To obtain the title filament having excellent handleability of precursor filament and high mechanical strength, providing spinning dope having excellent filament-forming properties and stability by subjecting an aqueous solution comprising a zirconium-containing compound, a partial stabilizer, etc., to dry spinning and burning.
CONSTITUTION: An aqueous solution obtained by blending (A) a zirconium- containing compound with (B) a partial stabilizer, (C) a compound to form SiO2 or B2O3 after burning in a weight ratio of SiO2 to zirconia of 0.5/99.5-10/90 or B2O3 to zirconia of 0/100-5/95 as a sintering auxiliary and (D) a spinning auxiliary (e.g. polyvinyl alcohol having 500-5,000 average molecular weight and 70-100mol% saponification degree) in a weight ratio of the spinning auxiliary to an oxide formed after burning of 5/95-50/50 is subjected to dry spinning to form precursor filament. The precursor filament is burnt to give the objective filament.
SUGISHITA TAKAAKI
NABEI EIJI
