| 摘要 |
PURPOSE:To stabilize image densities by changing the triboelectrostatic charge polarity of the fine particles of the silica to be used for a start developer and the triboelectrostatic charge polarity of the fine particles of the silica to be used for a replenishing toner. CONSTITUTION:The start developer consisting of a carrier toner and the fine particles P1 of the silica is previously supplied to the developing device of an electrophotographic copying machine and the replenishing toner consisting of the toner and the fine particles P2 of the silica is supplied in order to replenish the consumed start developer. The fine particles P1 and P2 of the silica are so compounded with the start developer and the replenishing toner that the respective triboelectrostatic charge quantities of the toner, the fine particles P1 of the silica and the fine particles P2 of the silica, destinated as A, B1 and B2, with respect to the carrier, maintain the relations of the triboelectrostatic charge polarities that B1 is a reverse polarity and B2 is the same polarity with regard to the triboelectrostatic charge polarities of A, then the development is executed. The increase in the initial triboelectrostatic charge quantity at the time of continuous copying is prevented in this way and the stable image densities are obtd. |
