| 摘要 |
PURPOSE:To improve fixing effect and offsetting property of a toner for developing electrostatic images by constituting the toner of binder resin consisting of a specified styrenic low molecular weight copolymer and a specified styrenic high molecular weight copolymer mixed in specified proportion. CONSTITUTION:The toner consists of a binder resin constituted of a styrenic low molecular weight copolymer (A) having 1X10<3> - 2X10<4> weight average mol.wt. and <=3 ratio of the weight average mol.wt/number average mol.wt., and contg. no addition-polymerizable monomer having no COOH group, and a styrenic high molecular weight copolymer (B) having 1.5X10<5> - 8.0X10<5> weight average mol.wt. and >=1.5 ratio of the weight average mol.wt./number average mol.wt. and contg. addition-polymerizalbe monomer having COOH group within a range of <=1.0 acid value, wherein a proportion of (A) to (B) is 80-20:20-80. Thus, a toner having improved offsetting resistance and fixing effect is obtd. |
