Patent ID: 9012120
Filing Date: 2015-04-21
Classification: G03G

Abstract:
1. A production process of a toner for electrostatic image development, which is composed of toner particles containing a binder resin, the process comprising: an aggregating step of adding an aggregating agent composed of a compound having a divalent or trivalent metal element into a dispersion in which fine particles of the binder resin have been dispersed in an aqueous medium, thereby aggregating the fine particles of the binder resin to form aggregated particles; and an aggregation terminating step of adding an aggregation terminating agent into an aggregating system of the aggregated particles, thereby terminating the growth of the aggregated particles, wherein the aggregation terminating agent is composed of a compound having both a structure (1) represented by a formula (1) below and a structure (2) represented by a formula (2) below, in the formula (1), R 1 to R 4 each represent a hydrogen atom, a hydroxy group or an organic group, and these may be the same or different from each other; however, at least one of R 1 and R 4 represents a hydroxy group; and, at least two of R 1 to R 3 may be bonded together to form a monocyclic structure or a polycyclic structure, in the formula (2), R 5 to R 9 each independently represent a hydrogen atom, a hydroxy group or an organic group, however, at least one of R 5 and R 6 represents a hydroxy group.