| 摘要 |
PROBLEM TO BE SOLVED: To obtain a good-quality image having little ID defect such as thinning even when the electrification amount of toner is lowered by providing a means for correcting a reference value so that the difference of the reference value caused by the difference of cumulative driving time may be less as absolute humidity gets higher. SOLUTION: Though the correction amount of T/D (toner concentration) in each driving time is different every driving time in a range where humidity does not exceed the absolute humidity at the time of normal temperature and normal humidity, it is constant to the absolute humidity. In a range where the humidity is higher than the absolute humidity at the time of normal temperature and normal humidity, the correction amount is set so that the value of T/D may be gradually lowered when the cumulative driving time of a photoreceptor drum is less than the time a little over 1050 minutes, for example. In such a case, the correction amount is set so that the value of T/D in the cumulative driving time may be converged as the absolute humidity gets higher. It is trouble that the electrification amount of the toner is lowered in an area B, but the electrification of the toner is accelerated by lowering the value of T/D and decreasing the absolute amount of the toner in developer. |
