| 摘要 |
PURPOSE:To maintain an appropriate amount of electrification on a toner carrier and to prevent the occurrence of ghost over a long period by using the specific main binder and subbinders as binder resin. CONSTITUTION:The ruggedness caused by plural spherical hollows is formed on the toner carrier (sleeve) by regular size grains in a blast- process. Vinyl- based binder resin incorporating 10-60wt.% of THF insoluble matter of the binder resin is incorporated in a binder resin incorporating negatively electrostatically charged toner as a main binder. In addition, as subbinders the binder resin a binder resin which has an amino group and whose amine value is 10-200 and a binder resin composed of conjugated diene based monomer or a binder resin composed of conjugated diene based monomer and one or more other monomers are incorporated. Thus, magnetic toner which is negatively electrified suppress excessive electrification on the toner carrier, and the occurrence of ghost can be prevented over a long period. |
