Links between fluid rheology and drop-on-demand jetting and printability

摘要

This paper links measurements of jetting performance in drop-on-demand printing with the high-frequency Theological properties of model viscoelastic fluids containing linear polymers with various molecular weights.rnJet formation and evolution were studied for solutions of polystyrene in diethyl phthalate. Ligament length, initial jet ejection speeds and ligament extension and retraction rates were determined by high-resolution imaging with high time resolution. For these fluids, the viscosity measured under low shear-rate conditions showed no correlation with their jetting performance. The jetting behavior was, however, well correlated with high frequency Theological properties measured at 5 kHz with a piezoelectric axial vibrator (PAV) rheometer.rnThis study shows that high frequency rheometry can provide useful predictive data about the jettability of fluids, and differentiate between inks that have similar low shear-rate viscosity yet show different jetting behavior.