| 摘要 |
PURPOSE:To obtain a picture image having high quality by incorporating at least a colorant, a charge regulating material, and a specified compd. into a binder resin. CONSTITUTION:A colorant, a charge regulating material, and a compd. expressed by the formula I are incorporated into a binder resin. In the formula, R is an organo group; M is a metal; (m) is a valency of the metal. The reason why this compd. is superior as a positive charge regulating material is considered to be attributed to a fact that the moiety of M-O-B bond in the formula has an important function as a charge regulating material. Accordingly, there is no fundamental restriction concerning the kind of R in the formula, but such group having thermal stability and serving to improve the affinity to the binder resin, and increasing the charge density of the metal atom, is preferred. By this constitution, a positively charged toner having stable quantity of frictional electric charge, and sharp and uniform distribution of frictional charge, is obtd. |
