| 摘要 |
A toner includes a polyol-based resin having multiple hydroxyl groups in a molecular chain thereof in which a ratio of epoxy group to hydroxyl group is from 0.990 to 1.010. A stirring and transfer device satisfies 1000000≦̸α×&bgr;×γ≦̸16000000, wherein α represents a number of rotation per minute, &bgr; (mm) represents a pitch and γ (mm) represents a transfer path length of the stirring and transfer device. A temperature Tin (° C.) in a development device during stirring and transfer of a two component developing agent satisfies 3020 C.<Tin<60° C., and the toner satisfies Y≦̸−0.5X+45, 5≦̸X<40, 5≦̸Y≦̸35, wherein X (%) represents a degree of agglomeration of a mother toner particle and Y (%) represents a degree of agglomeration of the toner which has been preserved at 55° C. for 24 hours.
|
