Microcapsule toners were prepared in two steps: fine core particles and the wall of the capsule were prepared in the first and the second steps, respectively. The core material was stearic acid in which carbon black was dispersed. The wall material was the fine polystyrene beads prepared by the soap-free polymerization. In the experiment, operating conditions, such as the volume fraction of stearic acid and the impeller speed and the mixing time in the preparation of the first 0/W dispersion, were changed stepwise. It was investigated that how the operating conditions affected the properties of microcapsule toners, such as the size distribution, the mean size and the contents of ferrite powder and the wall material. The mean size of the toner decreased with the increase of the impeller speed and the mixing time (D&lt
inf&gt
AV&lt
/inf&gt
œ:Nr&lt
inf&gt
1&lt
/inf&gt
&lt
sup&gt
-1.2&lt
/sup&gt
, D&lt
inf&gt
AV&lt
/inf&gt
œt&lt
inf&gt
1&lt
/inf&gt
&lt
sup&gt
-0·48&lt
/sup&gt
). The content of the wall material increased with the polymerization time.