| 摘要 |
PURPOSE:To provide the toner which exhibits a high electrical conductivity in a low electric field and has excellent fixability and reliability and to obtain high image quality by coating inside nuclei with a specific carbon black. CONSTITUTION:The carbon black is dispersed at 1 to 10wt.% uniformly into a binder material to form the nucleus particles which exhibit 10<3> to 10<7>OMEGAcm resistivity to 100V/cm electric field as the inside nuclei. The carbon black having >=200cc/100g DBP oil absorption is fixed at 0.1 to 20wt.% of the weight of the inside nuclei to the outside surface of the inside nucleuous particles to form the shell. This carbon black is a porous material in which the structure is developed so that the carbon black can be formed to a large grain size. Such carbon black exhibits the good electrical conductivity even when embedded into the resin. The surface conductive paths are, therefore, extremely easily formed and the sufficiently conductive toner is obtd. even is the surface is not completely coated. The electrical conductivity in the low electric field is surely exhibited in this way and the fixability, reliability and image quality are maintained at a high level. |
