Fig. 1. Diagrams generated by modified Wilhelmy balance test. (A) Surface spreading rate test. Synsurf-1 was slow. Synsurf-2 and -3 and Surfacten® were similarly fast in regards to surface spreading rate test. (B) Surface adsorption was best for Synsurf-3, followed by Surfacten®, Synsurf-2, and Synsurf-1 in that order. (C) In surface tension area diagram, all four preparations showed hysteresis curves. Among these, Surfacten® showed the lowest minimum-ST, which was the best. Synsurf-2 and -3 showed similarly in the middle and Synsurf-1 was the worst. ST, surface tension.