Abstract
Hysteresis of contact angle, defined as the difference between advancing contact-angle and receding contact-angle, is an index of the mobility of droplets. Measurement of hysteresis of micro-droplets is difficult and spreading mechanism has not been made clear. This paper aims to measure the hysteresis of micro-droplets obtained with equipment like ink-jet printer and make clear the effect of droplet size and substrate conditions. The hysteresis was measured by analyzing the observed image sequences along with the evaporation. It was found that the hysteresis decrease with the decrease in droplet size. Finally, the effect of microstructure fabricated on the substrate on the hysteresis was also made clear.
