Abstract
When the hydrophobic fine powders were dosed into water, they spread over the water surface as an oil does, whereas they were easily dispersed into acetone. These hydrophobic fine powders were dosed into the aqueous acetone solutions with several concentrations, and the surface tensions of them were the values between that of water and acetone. The surface tension of the solutions into which the powders easily dispersed was determined. The surface energy of these powders was estimated from the thermodynamic consideration on the interface between powder and solution. The surface energy was also estimated for the powders which were easily dispersed into water, whereas they were collected into the interface between water and hexane after adding the hexane to these aqueous suspensions and shaking these suspensions.
