| 摘要 |
PURPOSE:To reduce toner scattering, and further ground fogging due to stains in a copying machine by externally adding an imidazole or its derivative specified in volume average particle diameter and external addition amount. CONSTITUTION:The developer comprises a carrier and a positively chargeable toner and the external additive particles containing the imidazole or its derivative, for example, represented by formula I in which R1 is H or lower alkyl; R2 is H, alkyl, or cycloalkyl, and R3 is H or methyl. These external additive particles have a volume average particle diameter of 0.1 - 100 mum and they are added in an amount of 0.001 - 5 wt.% of the toner. These derivative particles are usually positively charged by friction with the carrier particles and attached to the toner particles, thus permitting scattering of the toner and further, ground staining due to stains inside the copying machine to be both reduced. |
