Patent ID: 7266995

Claim:
A method of measuring surface tension at the interfacial surface between a liquid and a fluid, the liquid having a larger density than the fluid and being substantially non-miscible therewith, the method including: having the liquid flow in one direction through a capillary for forming successive liquid drops that are denser than the fluid at an end of the capillary positioned in a closed space in a vessel containing the fluid, wherein the formed successive drops fall from the end of the capillary and are received in the closed space, measuring a pressure of the fluid in the closed space with the closed space disconnected from the atmosphere so that the pressure measured in the closed space is independent of the atmospheric pressure to provide a pressure measurement signal while the liquid is flowing through the capillary and is forming drops, and evaluating the pressure measurement signal to provide a value of the static surface tension between the liquid and the fluid in the closed space.