摘要 |
<p>PROBLEM TO BE SOLVED: To provide a toner which can ensure sufficient developing property, without causing decrease in the life time of a developer carrying body, even if the process speed is increased, and to provide an image forming device and a process cartridge which use the above toner. SOLUTION: In the image forming device, the peripheral velocity of the photoreceptor is >=150 mm/sec, and the toner in the developer contains at least a binder resin and a magnetic material and has 5 to 12μm weight average particle size. The toner used has properties with the particles of the toner having >=3μm diameter calculated as circles in the toner contain particles, having >=0.900 circularity a by >=90% in terms of the cumulative value, based on the number and the toner satisfying the following conditions (a) or (b). (a) The cut rate Z and the weight average particle size X of the toner satisfy the relation Z<=5.3×X, and the cumulative value Y of particles having >=0.950 circularity based on the number, and the weight average particle size X of the toner are in the relation of Y>=exp5.51×X-0.645. (b) The but rate Z, X and Y satisfy Z>5.3×X and Y>=exp5.37×X-0.545.</p> |