| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device whose image forming speed is made high, which can maintain an excellent image over a long term and which can achieve the same effect even in the case of adopting simple device constitution of cleaning simultaneously with developing. SOLUTION: A latent image on a photoreceptor drum 101 having circumferential speed V1 is contact-developed by a reversal developing system by a developing device 103 whose developing roller has circumferential speed V2 by driving at 75 mm/s<=V1<V2. The toner carrying surface of the developing roller 1 is formed of a low frictional material satisfying 0.01<μ<(15/100000)×(R-100)2+0.16 assuming that the roundness of toner defined by a shape factor SF-2 is R for the coefficient of dynamic frictionμto SUS in the toner carrying direction of the toner carrying surface in order to restrain the application of excessive momentum from the toner carrying surface and make toner carrying force uniform and constant. |
