| 摘要 |
PURPOSE:To enhance fluidity and stability of triboelectric characteristics by forming one or more coat layers made of polymer particles alone or contg. a magnetic powder on a coat layer made of a mixture of the magnetic powder and fine polymer particles. CONSTITUTION:Core particles made substantially of spherical polymer particles and a magnetic powder are uniformly dispersed into a disperse system of fine polymer particles, and they are spray dried at the glass transition point of the fine polymer particles or higher to form the first coat layer 2 made of the mixture of the polymer and the magnetic powder on the surface of each core particle 1. Further, the second coat layer 3 and the third coat layer 4 made of the polymer particles alone or contg. the magnetic powder are formed likewise on the first layer to obtain an electrostatic charge image developing magnetic toner. Said spherical polymer core particles are made of a thermoplastic resin, such as acrylate or polystyrene, and each has 1-20mum particle diameter. |
