PRODUCTION OF ULTRA-FINE FIBER

摘要

PURPOSE:To obtain ultra-fine fibers without any remaining unsplit fibers by pressurizing splittable type conjugate fibers before dissolving a polymer constituting the conjugate fibers. CONSTITUTION:This method for producing ultra-fine fibers is to pressurize conjugate fibers, preferably peelable and splittable type conjugate fibers comprising a polyester containing a polyoxyethylene-based polyether and a polyester containing ethylene terephthalate unit as a main recurring unit at a temperature of the second order transition point of the polymer or below with a calender roll (under 5-60kg/cm linear pressure) before dissolving a readily soluble polymer in the fibers. The resultant polyester-based ultra-fine fibers have a high dissolution rate and are capable of readily and completely dissolving the readily soluble polymer without any remaining unsplit part.