| 摘要 |
<p>PURPOSE:To obtain a polyester-base electrophotographic toner excellent in fixing characteristics by mixing two kinds of polyester resin having different softening temp. at a specified mixing temp. or lower to be used as the main component of the binder. CONSTITUTION:A polyester resin and a water-soluble org. compd. are mixed to satisfy anti-offset property and anti-blocking property. In this process, 100 pts.wt. of polyester resin having softening temp. between >=60 deg.C and >=95 deg.C and 0.1-100000 pts.wt. of polyester resin having softening temp. between >=100 deg.C and <=200 deg.C are mixed at <=100 deg.C, preferably at temp. lower than the lower softening temp. of the resins. Then water is added to oxidize with water, remove the solvent, and then an electrolyte is added to loosely aggregate to obtain toner particles. By this method, mixing is executed at temp. lower than the softening temp. of the resin so that by-reaction during mixing can be prevented. Thereby, the obtd. toner shows excellent image forming performance without causing contamination of producing devices and the obtd. image has high storage stability.</p> |
