| 摘要 |
PURPOSE:To decrease the reduction of magnetic permeability of toner particles and to obtain a toner which causes little contamination on the print base and has good fixation property by depositing fine resin particles having smaller particle size than the inner core on the inner core, and further forming a dissolved resin coating layer comprising the resin fine particles and magnetic powder. CONSTITUTION:The inner core particles 9 are obtd. by premixing a binder resin 1 and colorant 2, heating and kneading, cooling, pulverizing and controlling the particle size by classification. In the process 10 to deposite resin fine particles 3 of smaller particle size than the particles 9 as the outermost shell layer on the particles, a fast fluidizing mixer is preferably used as a device to cause the mechanochemical reaction to the mixture of particles. Then the resin fine particles 3 are dissolved with a solvent in which magnetic powder 4 is dispersed to form the dissolved resin coating layer containing the magnetic powder 4 as the outermost shell. In this process, it is preferable to use a powder coating device which can minimize and control the contact time of the solvent. Thereby, enough magnetic permeability can be obtd. with a small content of the magnetic powder, and the obtd. toner causes little contamination in a nonpicture area and has good fixation property. |
