DEVELOPING METHOD FOR ELECTROPHOTOGRAPHIC IMAGE AND DEVELOPING DEVICE, AND PRINTING DEVICE USING THE DEVELOPING DEVICE

摘要

A developing device for electrophotographic images, comprising a developing mechanism having a developer carrier for conveying a developer along a preset circulating route including a developing area and a developer restricting element for restricting the developer on the developer carrier, and a developer supply mechanism having a developer storing means. The developer storing means is filled with a start-up developer in the vicinity of the developer carrier and a replenishing developer remoter than the start-up developer from the developer carrier. The start-up developer and replenishing developer have different grain sizes or grain size distributions, whereby preventing variations in printing density within forms, printing history (after image, ghost) and density-lowered printing that may be encountered at an initial state of use of a developing unit and after toner cartridge replacing/toner replenishing to thereby provide constant printing images.