| 摘要 |
PURPOSE:To stabilize triboelectrifiability even after uses for a long term or under high temperature and high humidity or under low temperature and low humidity by regulating the triboelectrification quantity of a positively electrifiable toner and a mixture of said toner and a positively electrifiable fine silica powder. CONSTITUTION:The developer contains the positively electrifiable toner (A), a positively electrifiable fine silica powder (B), and a fine fluororesin powder (C). The electrification quantity of the component A TA is regulated to TA>=20muC/g, and that of the mixture of the component A and the component B TB is regulated to 1<=TA/TB<=3. The component A contains a copolymer having 2-15wt% aminoacrylic monomer units, such as dimethylaminoacrylate, in an amount of >=30wt% of the total binder resin, and the component B is, preferably, a fine silica powder treated with a silicone oil having an amine group on the side chain, and the component C may be fine particles of polyvinylidene fluoride or polytetrafluoroethylene. |
