| 摘要 |
PURPOSE:To obtain the charge controller capable of narrowing of charge amount distribution and stably maintaining correct charge amount when added to a toner. CONSTITUTION:The charge controller is made of a graft copolymer A of a polymer chain 1 composed of monomer units each having a functional group selected from a carboxylic group and its salt, a thiophenol and its salt, and a sulfo group and its salt, and a polymer chain 2 compatible with a toner binder. For example, as the polymer chain 1 having functional groups, an amino acid type monomer, and as the polymer chain 2 compatible with the toner binder, polystyrene are preferable, and the preferable charge controller is the graft polymer of these polymer chains. |
