PURPOSE: To obtain a water-based ink, containing a specific water-soluble dye, capable of giving clear images having excellent light and water resistance without precipitating during preservation and clogging nozzles and useful for ink jet recording, printing, writing utensils, recorders, etc.

CONSTITUTION: A composition containing at least one water-soluble dye expressed by formula I [R1 is OH or (substituted) amino; R2 is H, OH or (substituted) amino; M is H, alkali metal, quaternary ammonium or basic amine; Ar is (substituted) aryl; m is 0 or 1; n is 1 or 2]. The content of the dye is preferably 1.5W6.0pts.wt. based on 100pts.wt. ink.