Stable aqueous composition for improving light fastness

PURPOSE: To obtain an aqueous composition for improving the light fastness of dyed polyester fibers or polyester mixed fibers by incorporating specified amounts of a specified benzotriazole compound, an aromatic sulfonic acid- formaldehyde condensation product and a nonionic dispersant. CONSTITUTION: The aqueous composition contains (A) 15-60 wt.% benzotriazole compound of the formula (where R 1 is H, 1-4C alkyl or 1-4C alkoxy, preferably 3-tertiary butyl; R 2 is H, 1-4C alkyl, 1-4C alkoxy or sulfo, preferably 5-methyl; and R 3 is H or halogen, preferably H), (B) 0.5-11 wt.% condensation product of an aromatic sulfonic acid having no ether bridge in the aromatic nucleus and formaldehyde, preferably naphthalenesulfonic acid-formaldehyde condensation product and (C) 0.5-20 wt.% nonionic dispersant. COPYRIGHT: (C)1990,JPO