| 摘要 |
PURPOSE:To allow the sure formation of a magnetic toner to paper and the stable transportation of the toner by constituting a developer of the magnetic toner and a polarity charge accelerator to be electrostatically charged to the polarity reverse from the polarity of the toner. CONSTITUTION:A developing device is constituted by having a developing roll in a developing container and housing the developer consisting of the highly magnetic toner having a minus polarity and the charge accelerator constituted of magnetite or ferrite into the developing container. The material for the charge accelerator is selected from the requirements that the order in an electrostatic charge system be parted, that only the toner be splashed and the charge accelerator be not splashed, that the toner concn. be decreased by the development of the toner and the charge accelerator do not splash even if the mixing ratio with the charge accelerator changes, etc. The grain size of such charge accelerator is preferably 5 to 20mum and the sure recording and the stable transportation of the developer are attained in this range. |
