Direct Orange 5

Preparation

aniline diazo, and 7-(4-Aminobenzamido)-4-hydroxynaphthalene-2-sulfonic acid coupling, and then diazo, and 5-Oxo-1-phenyl-4,5-dihydro-1H-pyrazole-3-carboxylic acid?coupling.

Properties and Applications

yellow orange. Moderate soluble in water for palm light orange, slightly soluble in alcohol. The strong sulfuric acid for orange red, to orange diluted. The dye solution to join strong hydrochloric acid have brown light orange precipitation; Add thick sodium hydroxide solution for orange brown. Can be used for cotton dyeing, good levelness. Neutral and alkaline white is very good. Hard to sensitive.