The synthesis and characterization of two hetarylazo disperse colorants are described. These compounds were used for the preparation of ink-jet inks with and without active agents for polyester printing. The viscosity, conductivity, surface tension, and pH of these inks were studied over a period of time and discussed with respect to their structure and the active agent content. The particle size and particle size distribution of a representative ink containing a new synthesized hetarylazo compound were measured. All the prepared inks were proved to be suitable for ink-jet printing in terms of their particle size. Viscosity, surface tension, conductivity, and pH values of all inks, with and without active agent, were monitored over a period of 90 days and were related to the ink stability. The same properties were measured for an ink preparation with a commercial dye for comparison. The inks containing the new synthesized dyes were found to be more advantageous regarding most of the above properties, i.e., surface tension, viscosity, and conductivity. Contrarily pH values of all the preparations were unacceptable for ink-jet inks. The ink compositions containing the new synthesized compounds were applied by exhaustion (dyed) on polyester fabric. Fastness properties of the dyed polyester samples were excellent to very good in most cases. Color measurements of the dyed fabric were also performed. A qualitative determination of the aroma-active agent adsorbed on the fiber by the exhaustion method was achieved by the GC-MS method. (C) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012