1. Toner composition: toner is a powder synthesized from chemical raw materials such as iron oxide, resin, colorant and silica.

2. The toner is divided into two types, one is magnetic powder.Such as (Canon, HP toner).The other is non-magnetic powder, which is divided into (Brother, Xerox toner, Epson).

3. Evaluation of the comprehensive quality of toner:To assess the overall quality of a model of toner, the following six factors could be considered: blackness, greyback, waste toner rate, resolution, fixation, ghostimage.These factors are interrelated and affect each other.