A true weight distribution is not produced as the method relies on measuring the second smallest dimension of the particle. This can produce strange results with rod-like materials such paracetamol. It is a low-resolution method and usually only four to five size classes are provided. Sedimentation This is the traditional method in the paint and ceramics industries and uses equipment as simple as the Andreason pipette or as complex as centrifuges and X-rays. However, as the density of the material is needed, it is no good for emulsions where the material does not settle, or for very dense material that settles too quickly.
Temperatures also require close monitoring in order to control viscosity.
Other disadvantages include slowness of measurement, which makes repeat measurements tedious. Irregularly shaped particles, such as disc-shaped kaolins, take even longer to settle due to their increased drag compared with spherical particles. 50m m. Electrozone sensing This technique was originally developed for sizing blood cells. For industrial materials it has many drawbacks. It is difficult to measure emulsions and impossible to measure sprays.