Fitzpatrick, Cella, Harper & Scinto
Image forming apparatus for forming color image with dry developer
 This invention relates to a color image forming apparatus for forming a color image with dry developer, capable of preventing deterioration of image quality, resulting from contamination of optical components by the non-magnetic developer scattered from the developing unit. For this purpose there are provided, along the moving direction of an image bearing member effecting endless movement, charging means, optical means, first developing means utilizing developer containing a magnetic component, second developing means utilizing non-magnetic developer of a color different from that of the developer of the first developing means, and transfer means maintained in contact with or close to the image bearing member for transferring a developed image from the image bearing member to a recording material such as paper. A space containing the second developing means is enclosed by the shape of the first developing means, transfer means and image bearing member. 
Canon Kabushiki Kaisha
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inventional inventional inventional inventional
Kimio Tatsuya Yasuo Masami Tohru Masahide Takashi Hiromichi Tohru Masuo Katsuhiko
Nakahata Nakamura Yoda Takeda Kosaka Hirai Shibuya Yamada Saitou Yamazaki Nishimura