Abstract
The equipment for measuring the wettability (i. e. the contact angle) of hydrophilic powder was newly developed, based on the so-called CST(Capillary Suction Time) method. This equipment has a feature in which the wetting liquid spreads horizontally and radially into the powder bed having a disk shape 2mm thick. The contact angle is calculated from the time (CST) which it takes for the wetting liquid to move from the 1st sensor to the 2nd one. The wetting front was detected by either an electrical conductance method or a reflecting light method.
The availability of this equipment was confirmed by investigating the effect of the type of sensor, the distance between the two sensors, the porosity of the powder bed, and the temperature, etc. on the contact angle of untreated aluminum hydroxide powder or that treated with stearic acid.
