| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a dry binary developer comprising a carrier rapid in rising of toner charge, and stable and good in charging performance, and a toner superior is pulverizability and classifiability and environmental stability and fixing stability, even after long storage, and high in triboelectifiability with the carrier and freed of attaching to a polyvinyl chloride sheet during storage of copied sheets. SOLUTION: This binary developer comprises the carrier composed of spherical grains each having a surface crystalline part roughened by molten discontinuous phases and its surface layer being coated with a resin coated layer, and a toner composed of a colorant and a binder resin and a charge controller. This binder resin comprises (1) an epoxy resin, (2) the alkyleneoxide adduct of a divalent phenol phenol or its glycidylether, (3) a divalent phenol, and (4) a polyol obtained by reacting a compound having an active hydrogen (reactive with an epoxy group) with an epoxy compound. This charge controller comprises a metal salicylate.</p> |
