| 摘要 |
PURPOSE:To produce the toner for developing electrostatic charge images effective for a negative chargeable toner by mixing a mixture obtd. by mixing two kinds of charge control agents by a dry process together with other toner components and melting and kneading the mixture. CONSTITUTION:The mixture obtd. by mixing at least two kinds of the charge control agents by the dry process is mixed together with the other toner components and the mixture is melted and kneaded. There is no particular limitation on the charge control agents to be used. The metal complex of a nigrosine dye, the metal complex of a salicylic acid (deriv.), (modified) nigrosine dye, colloidal silica powder, quaternary ammonium salt, etc., are usable for these agents. The combinations of the different compsn. groups with each other are preferable as the combinations of >=2 kinds; for example, the combination of the metal complex of the nigrosine dye and the metal complex of the salicylic acid (deriv.) or the like is used. The excellent stability of characteristics with lapse of time is obtd. in this way and the toner suitable for long-term continuous use is obtd. without generating fogging and toner splashing. |
