Jetting Frequency and Evaporation Effects on the Measurement Accuracy of Inkjet Droplet Amount

Abstract

Inkjet technology has been used as a tool to manufacture printed electronics, and the size of the droplet should be properly measured and controlled in order to improve the print quality. To this end, the volume of an inkjet droplet can be measured by assessing an image of the droplet through the use of a visualization system. However, a vision-based method may have accuracy issues, so, in this study, an alternative method is proposed by using a microbalance to measure the droplet mass. The mass and the volume of the droplet are simultaneously measured for verification and comparison. Since the results of the proposed mass measurement method are susceptible to the evaporation of liquid on the microbalance, the accuracy of the measurement is improved by employing an evaporation compensation method. Finally, the effects of the jetting frequency on the measurement uncertainty of the mass and the volume of the droplet are investigated by using several jetting materials with different boiling temperatures. (C) 2015 Society for Imaging Science and Technology.