Developing device, image forming apparatus, and process cartridge

摘要

A developing device configured such that an amount of weakly charged toner in a two-component developer passing through an opening in the device per unit time is not greater than 200 g.mm/min, wherein the amount of weakly charged toner is expressed by an equation, which is $\begin{array}{c}\mathrm{the}\mathrm{amount}\mathrm{of}\mathrm{weakly}\mathrm{charged}\mathrm{toner}\left[g.\mathrm{mm}\text{/}\min \right]=\mathrm{total}\mathrm{amount}\\ \mathrm{of}\mathrm{the}\mathrm{two}\text{-}\mathrm{component}\mathrm{developer}\mathrm{to}\mathrm{be}\mathrm{drawn}\left[g\text{/}\min \right]x\mathrm{length}\\ \mathrm{of}\mathrm{the}\mathrm{opening}\left[\mathrm{mm}\right]xa\mathrm{concentration}\mathrm{of}\mathrm{toner}\left[\mathrm{wt}\%\right]x\\ \mathrm{percentage}\mathrm{of}\mathrm{weakly}\mathrm{charged}\mathrm{toner}\left[\%\right].\end{array}$