Abstract
The effect of electrolytes on the drainage and the rupture of the thin liquid film formed between the bubble and the flat solid surface approaching at a constant velocity has been investigated experimentally. The transient thickness distributions are measured by the interferometer with high-speed observation. 0.05 M MgSO_4 solution and 0.05 M CH_3COONa solution are used as electrolyte solutions. The surface shape changed from pimple shape to dimple shape as 3 mm bubble approaches to the flat surface, and the effect of the electrolytes on the drainage process was negligible in the present cases. On the other hand, in 0.05 M MgSO_4 solution, the timing of the rupture retarded compared to that in the case with purified water.
