dispersion

– The process of breaking the pigment agglomerates down to the optimum size, often using high shear equipment and effectively ‘wetting’ the particles within the polymer matrix/host medium.

Distribution

– How well these particles have been evenly scattered throughout the polymer matrix/host medium. 

The size and distribution of these particles gives the article the colouristic and optical properties.

This refers to the context of plastics.

An example of poor distribution: