| 摘要 |
PURPOSE:To prevent decrease of image density and increase of fog by incorporating a toner powder and a fine acrylic/styrene including its deriv. copolymer powder having an average particle diameter smaller than that of this toner powder to prepare a developer. CONSTITUTION:A developer contains a mixture of a toner powder, e.g., having an average particle diameter of 3-20mum and a fine acrylic/styrene including its deriv. copolymer powder having that of 0.05-5mum, preferably, 0.1-2mum in an amt. of this fine powder of 0.01-10wt%, preferably, 0.05-2.0wt% of the toner. Said acrylic/styrene including its deriv. copolymer to be used for this fine powder is prepared by dissolving a copolymer obtained by the various polymn. processes, such as emulsion or suspension polymn. process, in a solvent, and granulating it by the spray drying process to form fine granules, or said fine powder is prepared also by mechanical pulverization. |
