4-Dimethylaminoazobenzene is a yellow, crystalline solid compound. 4-Dimethylaminoazobenzene was used as a dye for coloring polishes, wax products, polystyrene and soap, and was also used as a pH indicator, but is no longer used or produced in the United States. Exposure to this substance causes dermatitis. 4-dimethylaminoazobenzene is reasonably anticipated to be a human carcinogen.