| 摘要 |
PURPOSE:To restore a developer and to save time necessary for exchanging it, and to use it as long as possible, by adding a dye reverse in chargeable polarity to the develper deteriorated in chargeability characteristics. CONSTITUTION:A charge controller opposite in charging polarity to a toner is added to the developer high in chargeable amt. once deteriorated and giving an image low in image density. For example, the toner is positively chargeable, a dye contg. a metal, such as Cr or Co, or a phthalocyanine pigment, etc. are preferable. As an execution example, a developer used contained a mixture of 3,000g carrier and 200g toner consisting of 100pts. polystyrene, 5pts. nigrosine, and 6pts. carbon black, and the developer is deteriorated in image quality by 200,000 cycles of copying, so at that time, a Cr dye as a negative chargeable controller was added by 1% of the toner weight, resulting in restoring image density and charging amt. nearly to the initial state. |
