Orange powder. Easily soluble in water, with a solubility of 60g/L at 20°C and 130g/L at 50°C. When dyed, the color turns slightly green in the presence of copper ions.
2,5-Diaminobenzenesulfonic acid diazo, and 5-Oxo-1-(4-sulfophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid coupling, and then and 2,4,6-Trichloro-1,3,5-triazine condensation .