| 摘要 |
PURPOSE: To obtain an image of high quality without white stripes by regulating a magnetic toner carried on a developer sleeve with an elastic blade, uniformly charging the toner, forming a toner thin layer on the developer sleeve without producing white stripes or the like and then developing the image. CONSTITUTION: The magnetic pattern of a regulating magnetic pole N1 of a magnet 2 housed in a developing sleeve 1 is controlled to be broad in the nip part where an elastic blade 3 and a developer sleeve 1 are in contact with each other. By this method, fluctuation of the magnetic flux density in the normal direction of the developer sleeve surface is controlled to <300×10<-4> T/mm, preferably <200×10<-4> T/mm. Therefore, since the fluctuation of the magnetic flux density in the nip part is decreased and the magnetic force is suppressed, aggregation or clogging of a magnetic toner 6 can be prevented. The toner 6 can be uniformly electrified and a toner thin layer without white stripes can be formed on the developer sleeve 1. |
