| 摘要 |
PURPOSE:To prevent the degradation in image density by charge-up even under low humidity by making a triboelectrostatic charge series to toner particles>fine powder particles>carrier particles or toner particles<fine powder particles< carrier particles. CONSTITUTION:The fine powder particles of a pigment, etc., having <=0.2 grain size ratio with respect to the carrier coated with a resin are passed through an impact section adjusted to 0.5 to 7mm shortest spacing between a rotating piece and a stationary piece or between two kinds of the rotating pieces under the conditions of 10 to 100 deg.C atmosphere temp. The carrier particles stuck on the carrier surface in the state of holding the fine powder thereon are obtd. and the carrier particles and the toner particles are mixed so that the triboelectrostatic charge series thereof is made to the toner particles>the fine powder particles>the carrier particles or the toner particles<the fine powder particles<the carrier particles. The charge-up hot only at and under ordinary temp. and ordinary humidity but under the low humidity as well is prevented in this way. |
