The influence of surfactants on the interfacial tension and droplet formation in UV curable jet inks

Abstract

Is the droplet formation predictable by physical measurements? How strong does the interfacial tension influence the droplet formation? In this paper commercial surfactants of the different classes made of organic, fluorocarbon and silicone chemistry were investigated. To verify their performance and ability of adjusting the interfacial tension, different methods of surface tension measurement such as static surface tension, dynamic surface tension and dynamic contact angle were utilized. Interesting results and analogies could be observed. The influence on the droplet formation of the used surfactants was evaluated on an actual piezo drop-on-demand printhead and compared with the results gained by the physical measurement. To keep the possible interactions and dimensions as small as possible, very simple model formulations based on PONPGDA and TMPEOTA were used. In this paper the authors search for correlations in order to give guidance for the best choice of surfactant.