Azo dye intermediate; photographic developing agent; photo- chemical measurements; intermediate in manufacture of antioxidants and accelerators for rubber; laboratory reagent; dye hair and fur; lithography; photocopying; oils; greases; gasoline and as antioxidant/accelerator in the rubber and plastic industry. The hydrochloride is used as blood reagent. Cross: parabens, PABA, para compounds. May produce erythema multiforme like eruptions. ABCD. PA. ICU.