| abstract |
A polylactic polyester resin comprising a chemical structure indicated by general formula (1), having an acid value of 300-2,500 eq/10 6 g, having a number-average molecular weight of 2,000-50,000, and having a lactic acid content of at least 40 wt%. Z-(O-(CH 2 CH 2 O) p -(CO-Y-O) q -X) r … (1). Z is an r-valent organic group; Y is -CH(CH 3 )- or a mixture of -CH(CH 3 )- and a C2-10 linear or branched alkylene group; X is a residue of a polybasic acid having at least two carboxyl groups, or hydrogen; and X, Y, and Z can be either a single type or a mixture of a plurality of types. p, q, and r are 0 or a positive integer; the average value of p is at least 0.5, the average value of q is at least 5, and the average value of r is 3-15. |