| 摘要 |
<p>PURPOSE:To provide a developer which causes only minor secular changes in fluidity and in electrification characteristics and stably displays excellent developing and transferring properties over a long period without generating fogging in the non-image area and wire side stain. CONSTITUTION:The developer comprises a toner obtained by adding inorganic fine particles as a component of it and a carrier having 20 to 60mum volume average particle size and the inorganic fine particles consists of one inorganic compound. In the distribution curve of the number of the inorganic fine particles vs. the primary particle size of the inorganic fine particles, there are two number fraction maxima at the particle size of x nm and y nm, wherein x nm, and y nm are in the ranges of 20<=x<=50 and 3x<=y<=6x respectively, and the number fraction at the particle size of (x+y)/2nm is <=10% and also the ratio (X/Y) of the number fraction in the range of <(x+y)/2nm particle size (X%) to that in the range of >=(x+y)/2 nm particle size (Y%) is 0.5 to 2.0. Further, the ratio (z/x) of the volume average particle size of the colored particles in the toner (z nm) to the above x nm of the inorganic fine particles in the toner is 150 to 400.</p> |
