Improved microscopic techniques for droplet size determination of emulsions

A novel, disposable cell for microscopic determination of the droplet size of emulsions is described. It is made from a piece of adhesive tape in which a hole has been punched which is placed between a glass slide and a cover glass. This cell is easier to fill with emulsions thickened to reduce Brownian motion and creaming than commercial counting chambers, and it prevents field flow. Droplet size averages and distributions obtained with this cell and another counting chamber agreed, provided that the emulsion viscosity was approximately 20 cp or higher. The sample size required to provide arithmetic mean diameters with a specified accuracy at a preselected confidence probability was calculated.