Binder resin composition for electrostatic image developing toners

Abstract

The present invention provides a toner for development of electrostatic images including a polyester-based resin and a polypropylene-based wax, which is excellent in fusing properties on a polypropylene film. The present invention relates to [1] a resin binder composition for toners for development of electrostatic images which has an endothermic amount ratio ΔHof not less than 0.10 and not more than 0.80, [2] a resin binder composition for toners for development of electrostatic images in which a volume-median particle size (D) of a wax as a whole contained therein is not less than 1 μm and not more than 50 μm; a volume-median particle size (D) of a small particle size component of the wax is not less than 20 nm and not more than 400 nm; and a content of the small particle size component in the wax is not less than 20% by mass and not more than 90% by mass, [3] a process for producing a resin binder composition for toners for development of electrostatic images in which a polypropylene-based wax is added to a reaction system prior to addition polymerization upon production of a composite resin as a resin binder; and [4] a toner for development of electrostatic images including the resin binder composition as described in the above [1] or [2].