| 摘要 |
PURPOSE:To produce a toner having superior fixability, offset and blocking resistances by mixing two kinds of copolymerized styrene-acrylic monomer resins each having a prescribed mol.wt. and a prescribed glass transition temp. in a prescribed ratio and by using the resulting composition having a prescribed melt viscosity as a binder for an electrophotographic toner. CONSTITUTION:A copolymerized styrene-acrylic monomer resin A having 1X10<4>-3X10<4> weight average mol.wt. and 60-70 deg.C glass transition temp. is mixed with a copolymerized styrene-acrylic monomer resin B having 2X10<5>-4X10<5> weight average mol.wt. and 55-65 deg.C glass transition temp. in 90/10-50/50 weight ratio of A/B. The resulting resin composition having <=10<4>P melt viscosity at 140 deg.C is used as a binder for an electrophotographic toner. The main action of the resin A is to improve the fixability and that of the resin B is to improve the offset resistance. When the melt viscosity exceeds 10<4>P, the fixability is deteriorated. |
