| 摘要 |
PURPOSE: To obtain a copolyester capable of providing a binder fiber having excellent color tone and adhesiveness in short polycondensation reacting time by using inexpensive raw materials. CONSTITUTION: In producing a copolyester having >=0.35 intrinsic viscosity from a raw material mixture consisting essentially of an aromatic dicarboxylic acid component containing >=10mol% phthalic anhydride and/or phthalic acid and ethylene glycol component, one or more kinds of compounds of metals selected from antimony, cobalt, tin, germanium, titanium and zinc as a polycondensation reacting catalyst are added to the reaction system in an amount corresponding to 0.1×10<-4> to 10×10<-4> mol based on 1mol acid component, and a sulfonic acid compound is added thereto in an amount corresponding to 0.1×10<-4> to 10×10<-4> mol based on 1mol acid component constituting the copolyester and total amount of the catalyst, and the sulfonic acid compound is added thereto so as to become >=1×10<-4> mol based on 1mol acid component constituting the copolyester, and polycondensation reaction is carried out at 250-280 deg.C.
|
