| 摘要 |
PURPOSE:To maintain stable and good electrostatic characteristics even when the environment at the time of making a copy varies from low temperature and low humidity to high temperature and high humidity and to obtain a sharp and good-quality image by incorporating 2 kinds of specified resins in a binder resin. CONSTITUTION:The binder resin comprises at least one of the resins A having a weight average molecular weight of 1X10<3> - 2X10<4> and one of the repeating units represented by formulae I and II in an amount of >=30wt.% of the total polymerization units, and at least one of the resins B having a weight average molecular weight of 5X10<4> - 6X10<5> and a glass transition point of <=120 deg.C, and the resin A has at least one of acid groups, such as -PO3H2, -SO3H, -SH, and phenolic OH groups, and cyclic acid anhydrides, thus permitting the electrophotographic characteristics to be stabilized even when environmental conditions vary from high temperature and high humidity to low temperature and low humidity. |
