| 摘要 |
PURPOSE:To obtain a wet type toner not forming agglomerated cakes, and superior in reproductivity of dots, and solid developing performance, by melting with heat a resin insoluble in solvents at normal temp. and meltable when heated, adding a charge controller, and then cooling them to precipitate the resin in very fine particles. CONSTITUTION:A thermoplastic resin insoluble in a solvent, such as toluene at normal temp. and melted when heated, such as partially saponified ethylene- vinyl acetate copolymer, is melted by heating, and a charge controller, such as cobalt naphthenate, is added to said melt and melted, and then cooled with stirring to precipitate a toner in very fine particles. The charge controller is sufficiently adsorbed to the toner particles. Then, stirring is stopped, the supernatant is removed, an electrically insulating solvent, such as hexane, is added to replace toluene, or the like solvent, and the unadsorbed charge controller is eluted. The wet type toner particles thus obtained do not produce agglomerated cakes for a long period, have superior development performance, and it can form superior image lines having high printing resistance when used for lithographic printing. |
