Acid red 88

Acid red 88 is an azo dye. Due to its intense colour, solid samples appear almost black. It is used to dye cotton textiles red. A closely related acid dye is Acid Red 13.

Preparation and use
It can be obtained by azo coupling of naphthionic acid and 2-naphthol. Instead of crystallising, it vitrifies when cooled or salted out of the solution.
 * naphthol_red_preparation.svg

This compound is used in the textile industry as a dye. It can also be used for research in photocatalysis (as degradation object).