Preparation of microemulsion based disperse dye inks for thermal bubble ink jet printing

This study describes the preparation of microemulsion inks based on commercially available disperse dyes for thermal bubble ink jet printing. The approach to make the inks is by formulating to form water-soluble emulsions (o/w), which were then optimized to reach a dynamically stable isotropic condition. The dyes in three primary colors-cyan, magenta, and yellow-were systematically investigated. Different species and amounts of dispersants, emulsifiers, and dyes were selected to prepare microemulsions after intense stirring. The system, D50/963H/ Pannox140/glycerin/water, performed excellently in particle size reduction and size stabilization. The surface tension, pH value, viscosity, and stability of the microemulsion inks meet the requirement of the applied printhead to provide both good printing quality and excellent printing consistency without clogging in the nozzle. The interaction between dyes and the microemulsion system can be comprehensively understood based on the results of particle size analysis, lightfastness, water fastness, and the characterization of printing quality. The low particle size-reducing efficiency can be attributed to the compatibility between dye and dispersant structures as well as particle aggregation. The lightfastness could be enhanced with smaller particle size but decreased with dye content. However, the water fastness of the preformed sample was identically high without being affected by the dye particle size in the range between 80 nm and 96 nm. The printing performance was found to be closely correlated with the dye structure and ink concentration. (C) 2007 Society for Imaging Science and Technology.