An optimally dispersed sample is the basic prerequisites for a reliable determination of the particle size distribution.

In most cases, agglomerates need to be degraded and the correct particle concentration of the sample material needs to be set. Basically, the dispersion process can be done in an air flow (dry dispersion) as well as in a liquid (wet dispersion). Numerous materials have to be measured by wet dispersion. This includes sticky materials such as clay or materials that tend to agglomerate when dry. Even with very fi ne powders with particle sizes smaller than about 10 μm, the agglomerates can often be degraded only incompletely using dry dispersion.