The method for determining contact angle
is as described in BS EN 828 [1]. A flat
sample of the substrate material is placed
underneath a syringe and a drop of liquid
is dispensed onto the substrate. The
silhouette of the drop is viewed through a
camera connected to a PC to capture video
images of the drop, see Figure 1. Image
analysis software is used to calculate the
contact angle. Water drop contact angle
measurements are made using distilled
water. Typically the angle is determined 1
second after the drop is placed on the
substrate surface.