Toner Material State Control in Xerographic Systems

Abstract

Control of toner materials state is important to maintain stable printing performance. Xerographic toners are typically blended with additives for adhesion control in development and transfer processes. 10-100 nanometer size surface additives are used to space toners away from the electrode surfaces, thereby lowering adhesion forces. However, in a developer housing, additives get buried into the toner over time due to the repeated mechanical stresses encountered. This is referred to as toner aging. Aged toners can have significantly higher adhesion forces and often perform poorly in development and transfer. This paper discusses models for estimating the surface additive coverage distribution on toners in the developer housing and its impact on development and transfer performance. Examples of toner material state control are presented.