| 摘要 |
PURPOSE:To obtain an electrophotographic toner always stable in quantity of electric charge and development performance by premixing a fixing resin and a magnetic material at a temperature lower than the softening point of this resin under the conditions of minimizing the dielectric tangent of the produced toner and melt kneading the obtained mixture and granulating it. CONSTITUTION:The fixing resin and the magnetic material and another mixing agent, when needed, are premixed at a temperature lower than the softening point of the resin under the conditions of minimizing the dielectric tangent or under those near the conditions before melt kneading the dispersed composition containing the resin and the magnetic material to manufacture the electrophotographic toner, thus permitting the dispersed state of the magnetic material in the resin to be maintained in the best conditions, the chargeability characteristics and the development characteristics to be maintained each in a constant superior level, deterioration of the toner with the lapse of time to be prevented, and an always sharp toner image high in density to be obtained. In addition, after the premixing, the obtained mixture is melt kneaded and granulated like the general manufacturing processes. |
