POLYESTER POLYMER WHOSE HEAVY METAL (ANTIMONY AND COBALT) CONTENT LEVEL IS VERY LOW, ITS PREPARATION METHOD AND POLYESTER FIBER PREPARED BY USING THE POLYMER

摘要

PURPOSE: Provided are a polyester polymer whose heavy metal content level is very low and which is suitable for the fiber source of clothes for a baby or an old man having the sensitive skin, its preparation method and a polyester fiber prepared by using the polyester polymer. CONSTITUTION: The polyester polymer contains 50 ppm or less of antimony and 1 ppm or less of cobalt and has an intrinsic viscosity of 0.40-1.80 dl/g and a b value (index of yellowness) of 4 or less. Preferably the polyester polymer is polyethylene terephthalate or polytrimethylene terephthalate. The polyester polymer is prepared by polycondensation using the sodium hydrate of titanium dioxide represented by (Me_nO)x·(TiO2)y·(H2O)z as a polycondensation catalyst and blue and red polysynthrens as a toner, wherein Me is a metal selected from Li, Na, K, Rb, Cs, Mg, Sr or Ba; n is 1 if Me is an alkaline earth metal and n is 2 if Me is an alkali metal; x is 0.0001-6; y is 1; z is 0.01-2; and the particle has a size of 15 micrometers or less.