Process for preparing highly dispersed metal oxides whose surfaces are modified by an ammonium-functional organopolysiloxane as a positive chargeable controlling agent for toners

摘要

The invention relates to a process for preparing highly dispersed metal oxides whose surfaces are modified by an ammonium-functional organopolysiloxane as a charge controlling substance for positive chargeable toners, in which the highly dispersed metal oxides are reacted with an organopolysiloxane which contains silicon-bonded terminal hydroxyl and/or alkoxy groups, diorganosiloxane units, in which the two organic radicals are monovalent hydrocarbon radicals, and siloxane units in which the organic radicals contain a positive charged nitrogen which is bonded to silicon via carbon.