PROBLEM TO BE SOLVED: To provide: a dispersion that is safe and has high fluorescence intensity and high light fastness； and a bioimaging fluorescent labeling agent using the dispersion.SOLUTION: A dispersion comprises a compound represented by the general formula in the figure, a surfactant, and water, where the compound is dispersed in the water. (R1 and R2 are each independently a substituted or unsubstituted aliphatic hydrocarbon group or the like； and Ar1 and Ar2 are each independently a substituted or unsubstituted aromatic hydrocarbon group or the like.)SELECTED DRAWING: NoneCOPYRIGHT: (C)2020,JPO&INPIT【課題】安全かつ高蛍光強度、高耐光性を有する分散体及び該分散体を用いたバイオイメージング用蛍光標識剤の提供。【解決手段】下記一般式で表される化合物と、界面活性剤と、水とを含み、下記化合物が水中に分散されてなることを特徴とする分散体。（Ｒ1及びＲ2は、夫々独立に、置換又は無置換の脂肪族炭化水素基等；Ａｒ1及びＡｒ2は、夫々独立に、置換又は無置換の芳香族炭化水素基等）【選択図】なし
