Polyurethane urea elastic yarn having improved dyeability and manufacturing method therefor

A polyurethane urea elastic yarn, the yarn comprising (a) a polyol including a first polyol and a second polyol;

• (b) at least one diisocyanates selected from the group consisting of 4,4′-diphenylmethane diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, butylene diisocyanate, and hydrogenated p,p-methylene diisocyanate;
• (c) at least one diamine chain extenders selected from the group consisting of ethylenediamine, 1,2-propanediamine, 1,3-propanediamine, 1,2-butanediamine, 1,3-butanediamine, 1,4-butadediamine, 1,6-hexanediamine, 2,2-dimethyl-1,3-diaminopropane, 2,4-diamino-1-methykyclohexane, 2-methyl-1,5-pentanediamine, 1,5-diaminopentane, 1,4-cyclohexanediamine, m-xylylenediamine, and mixtures thereof;
• and (d) at least one amine chain terminators selected from the group consisting of diethylamine, cyclohexylamine, n-hexylamine, and mixtures thereof,
• wherein the second polyol is polyethylene glycol;
• wherein the second polyol is mixed in 5.0 mol % to 20.0 mol % with respect to the total amount of the polyol, and the first polyol and the second polyol are materials different from each other, and the first polyol comprise at least one polytetramethylene ether glycol, propylene glycol or polycarbonate diol,
• wherein the polyurethane urea elastic yarn has an amine-terminated number of 20.0 meg/kg to 45.0 meg/kg.