| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a toner of a small particle size having excellent cleaning property with a blade and charge controlling property by fixing a charge controlling agent to the surface of pulverized particles, classifying the pulverized particles and then supplying the classified coarse particles again to the pulverizing process. SOLUTION: Aggregates of color resin particles which essentially consist of a binder resin and a coloring agent and are produced by a wet granulating method are mechanically pulverized in a dry state in the presence of a charge controlling agent to fix the charge controlling agent to the surface of the pulverized particles. Then the pulverized particles are classified and the classified coarse particles are again supplied to the pulverizing process. Namely, after the charge controlling agent is fixed to the surface of pulverized particles, the particles are classified to separate coarse particles and then the coarse particles are circulated to be supplied to the pulverizing process. In this method, a preferable mechanical pulverizing machine used to pulverize the aggregates is equipped with a cylindrical container (outer cylinder) 2 having grooves on its inner surface and a cylinder (inner cylinder) 1 having grooves on its outer surface which can freely rotate and is disposed inside of the outer cylinder 2 at a specified distance from the inner surface of the cylinder 2.</p> |
