Abstract
The influence of toner and carrier particle size on toner tribocharge has been studied by the measurement of dependence of toner q/m on toner concentration. The q/m of ferrite carrier (100 μm) and P1 toner (8.1 μm) developer is decreased with increasing toner concentration (Type II). However, the q/m of ferrite carrier (65 μm) and P1 toner (8.1 μm) developer is without dependence on toner concentration (Type I). The q/m of P2 toner (10.5 μm) and P3 toner (12.3 μm) for ferrite carrier (65 μm, 100 μm) shows always no dependence on toner concentration and constant value (Type I). In the case of iron carrier (100 μm), the q/m of P1, P2 and P3 toner are always decreased with increasing toner concentration (Type II). It was shown that a reason to change from Type II to Type I (from 100 μm carrier —P1 toner pair to 65 μm carrier— P1 toner pair) could be explained in some of number of toner particles that it sticks to one carrier particle. In other words, because there are many attached toner particles on 100 μm carrier, it becomes Nc < Nt, and because there are a little attached toner particles on 65 μm carrier, it becomes Nc > Nt, and toner concentration dependence of q/m is different each other. The dependence of triboelectric charging characteristics on toner concentration is governed by the relative difference of number of charging sites between toners and carriers. The relative difference of toner and carrier effective charging sites is very useful concept for the analysis of microscopic behaviour of two component systems.
