| 摘要 |
<p>PROBLEM TO BE SOLVED: To produce toner particles that give a halftone image, having stable image density and high image quality in an environment which ronges from high temperature and high humidity to low temperature and low humidity and which do not cause toner fusion to a photoreceptor. SOLUTION: A mixture containing at least a bonding resin and a colorant is melted, kneaded, cooled and pulverized with a pulverizing means. The resultant powdery staring material is introduced into a 1st classification step, using a rotary air flow classifying means with a horizontal rotor and a fine powder recovery tube which protrudes partly into the rotor and is classified into fine and coarse powders. The fine powder thus obtained is introduced into a 2nd classification step and is classified to obtain a classified product for producing toner particles. the coarse powder obtained in the 1st classification step is introduced as a body to be pulverized into an impact type air flow pulverizing means and is pulverized finely, mixed with the powdery starting material and is reintroduced into the 1st classification step.</p> |
