Abstract
In this paper we applied interferometric laser imaging technique to the measurement of ζ potential and diameter of bubbles in liquid. The experimental results showed that various methods for producing microbubbles did not make difference in the values of ζ potential. Helium and air were used as gas components of bubbles and it resulted no difference in the values. In order to understand the mechanism of charging characteristic of microbubbles, we changed the pH of the deionized water and added alcohols to the deionized water. The results showed that the absolute value of the ζ potential increased when the pH increased and higher molecular weight alcohol easily decreased the absolute value of ζ potential.
