Synthesis and Properties of Amide Derivatives of 4-N,N-Dialkylaminoazobenzenes

Several disperse dyes, derivatives of 4-N, N-dialkylaminoazobenzene having acetylamino, carbamyl, phthalimide or naphthalimide substituents have been prepared. Their spectral properties and reaction to heat were determined, and their usefulness was evaluated in terms of the sublimation fastness. It was found that the dyes containing a benzamide system with an unsubstituted NH group, similar to that in phthalimide and naphthalimide derivatives, show a high sublimation fastness due to their ability to associate.