| 摘要 |
<p>PROBLEM TO BE SOLVED: To efficiently produce an electrostatic charge image developing toner having <=10μm weight average particle size, preferably <=7μm, and a sharp distribution of the grain size. SOLUTION: A powder source material is introduced into a first classifying process which uses a rotary air flow classifying means having a horizontal rotor so that the material is classified into a fine powder and a coarse powder. The fine powder thus classified is introduced into a second classifying process to obtain a classified powder to produce a toner. The coarse powder classified in the first classifying process is regarded as a material to be pulverized and introduced into a specified collision type air flow pulverizing means to be finely pulverized. Then the pulverized material is mixed into the powder source material and then again introduced into the first classifying process to be circulated.</p> |
