A polycarboxylic acid mixture having a 1,3,6-hexanetricarboxylic acid content of 80 wt.% or higher, characterized by having a psychometric lightness L of 98 or higher, a chromaticness index a of -2.0 to 2.0, a chromaticness index b of -2.0 to 3.0, and a nitrogen content of 5,000 wt.ppm or lower.
POLYCARBOXYLIC ACID MIXTURE