Apparatus for determining the stability of foam

摘要

Apparatus for determining the stability of a foam comprising a light source (1), a foam sample cell (2), a light sensitive cell (3) having a linear output voltage- or current-exposed area relationship, a voltmeter or ammeter (9) connected to the light sensitive cell (3) and a device (11) responsive to the output from the voltmeter for integrating a voltage-time curve or a current-time curve directly and dividing this area by the difference in voltage or current between that observed in the absence of foam and that observed immediately after foam has been formed to give the average foam lifetime. The light source (1), the foam sample cell (2) and the light sensitive cell (3) are positioned in line and are enclosed in a light-tight box (4).