ABSTRACT
The general way of characterising the stability of foams or bubbles is the registration of some integral properties, such as the volume of a foam [1] or the creaming in an emulsion [2]. For liquid film studies, however, no direct correlation between film properties and adsorption layer characteristics on one side, or foam/emulsion stability on the other side do exist. Only few first attempts exist to correlate the properties of these different complexity levels [3]. Bubble and Drop Interfaces © Koninklijke Brill NV, Leiden, 2011
Since recently there are experimental tools available which allow mimicking the elements in foams or emulsions, i.e. to study the direct interaction between bubbles or drops, respectively. Of course, enormously difficult requirements result in order to control drops or bubbles on a realistic size scale of micrometers. While the dosing of µl and temperature constancy of ±1◦C is easily managed, such micrometer drops or bubbles would require dosing accuracies of 10−9 µl and temperature control of much better than 10−3 K. Hence, these tools are typically working with drops or bubbles with diameters of the order of 100 µm. In addition, however, they also allow to look into asymmetric systems like the interaction between a large and a small drop (bubble) and even between a drop and a bubble, as it is a realistic case in foamed emulsions, for example in cosmetics or ice cream [4, 5].
