Polymerization methods are replacing conventional pulverization methods in the manufacture of toner for electrophotographic systems, because demands for higher picture quality and color quality have created a need for smaller particles. Many functions are required of a toner. Among them, control of the toner shape is important as it affects adhesion to the photosensitive material and transfer to paper. Toner shape is evaluated by image analysis. A study of the most stable measurement conditions was made. The conditions were optimized through an L18 experiment, which succeeded in finding measurement conditions that raised the precision of the current measurement system.
