| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a developer having good electrification rising and high temp. storage property which prevents image noises such as fog and voids in an image even when a binder-type carrier is used in a combination with a positive charge toner by controlling the exposed amt. of a magnetic powder on the carrier surface to the amt. of the magnetic powder added to a specified value or higher. SOLUTION: This developer consists of a positive charge toner and a carrier prepared by dispersing a magnetic powder in a binder resin, and the exposed amt. of the magnetic powder on the carrier surface to the amt. of the magnetic powder added is controlled to >=5wt.%. If the exposed amt. of the magnetic powder on the carrier is <5wt.%, the probability of the toner to be in contact with the exposed region of the magnetic powder is low, which prevents good triboelectrification of the toner. Therefore, by controlling the exposed amt. of the magnetic powder to >=5wt.%, the probability of the positive charge toner to be in contact with the exposed region of the magnetic powder on the binder- type carrier surface is increased to enable good triboelectrification. Thereby, the electrification rising property is improved and a good image without image noises can be obtd.</p> |
