| 摘要 |
PROBLEM TO BE SOLVED: To provide a negatively charging-controlling resin for electrophotographic toners having excellent charging properties and, when used in electrophotographic toners, exerting high compatibility with binder resins and high dispersibility, causing no inhibition of the color of the toners and controlling the charge well. SOLUTION: The resin comprises an acrylamide sulfonic acid or an acrylamide sulfonate of formula (1) (wherein, R<SP>1</SP>to R<SP>4</SP>are each a hydrogen atom, an aliphatic group or an aromatic group and optionally identical or different; and X is a hydrogen atom or an alkali metal), styrene and/orα- methylstyrene and a (meth)acrylate as structural units. The resin is synthesized under polymerization conditions: 0.5≤C/D≤1.5 for B≥0 and A/B≤0.5 (wherein, A and B are the rates of polymerization during reaction and at the termination of the reaction, respectively; C is the content, mass%, of acrylamide sulfonic acid; and D is the content of the acrylamide sulfonate in the polymer obtained at each of the rates of the polymerization). COPYRIGHT: (C)2004,JPO |
