Studies on the synthesis of 4,4'-diaminodiphenylurea and direct dyes derived therefrom

摘要

4,4'-Diaminodiphenylurea has been synthesized as a potential substitute for benzidine,by a reaction between urea and para-phenyldiamine in water.The synthesis is straightforward and economical,and produces a high quality product.The title compound was used to prepare direct dyes for cotton.The color and fastness properties of the dyed fabric were assessed,and the results showed that the dyes have good substantivity and light fastness.