Disperse ink-jet inks: properties and application to polyester fibre

Water-based ink-jet inks were prepared using press cake samples of two commercially available azo disperse dyes. The suitability of the inks for printing polyester fabric was evaluated via measurement of surface tension, conductivity, viscosity, pH and particle size distribution. Inks prepared by the proposed method fulfill most requirements for an ink-jet ink depending on the colorant structure, the dispersing agent and the alcohol used. The inks were applied to polyester fabric by both printing and dyeing and the fastness of the ensuing coloured samples was assessed. The fastness properties of the dyed and printed polyester samples were found to be very good to excellent and generally meet accepted customer requirements. Oil-in-water microemulsions containing the same colorants were also prepared. Their properties, which are crucial to the suitability for ink-jet ink, were compared with those of the conventionally prepared inks and were found to be improved, with the exception of conductivity, while surface tension remained within acceptable values.