It is an object of the present invention to provide a process unit and an image forming apparatus in which generation of loss of image density due to flying off of developer and the edge effect occurring as a side-effect under developing conditions aimed at improving development performance can be reduced,...http://www.google.ca/patents/US7457570?utm_source=gb-gplus-sharePatent US7457570 - Image forming apparatus including a magnetic brush developing system using a two-component developer comprising toner and carrier
