Comparison of Fumed and Colloidal External Additives for Toner

Abstract

External additives play a very important role in the performance of toner. They were originally used to adjust the toner freeflow and fine-tune its tribocharging performance. Recent trends towards color chemically produced toner have brought changes in the toner particle size and its composition. These changes have put even higher performance demands on the additives. For example, larger contribution to the tribocharging control for both positive and negative charging toner, requirements for spacing and durability for dual component toner, control of surface energy for more efficient toner transfer. Cabot offers a portfolio of modified silica additives that cover a unique range of morphologies, particle sizes and surface chemistries. In this paper we will compare the performance of treated silica additives with similar surface chemistries and different morphologies to explore some of the similarities and differences of colloidal and fumed silica-based products. Coverage, tribocharging, and freeflow are the key functions that are studied for dual component negative toner systems.