| 摘要 |
PURPOSE:To obtain a high quality image in any environment by mixing a nonmagnetic toner contg. a colorant dispersed in a resin binder with inorg. fine particles surface-treated with polysiloxane having an ammonium salt as a functional group. CONSTITUTION:A nonmagnetic toner contg. a colorant dispersed in a resin binder is mixed with inorg. fine particles (silica) surface-treated with polysiloxane having an ammonium salt as a functional group. The polysiloxane is preferably dimethylpolysiloxane having high positive chargeability and hardly causing defective cleaning. The amt. of the inorg. fine particles used is 0.1-5wt.%, preferably 0.1-2wt.% of the amt. of the nonmagnetic toner. The resulting developer ensures high image density and high developing property even at high temp. and humidity and a high quality image free from fog is obtd. |
