| 摘要 |
PURPOSE:To prevent a toner absorbing moisture so that the toner exhibits good fluidity even at and under high temp. and humidity and that an image having high quality is obtd. by sticking carbon black subjected to a hydrophobic treatment to the surface of toner particles. CONSTITUTION:A resin and a coloring agent and mixed and the mixture is spheroidized by a pulverizing method or spray drying method to prepare spherical toner particles. The carbon black subjected to a hydrophobic treatment by acting a hydrophobic agent such as dimethyldichlorosilane, octylmethaoxysilane or hexamethyldisilazane, etc. is stuck to the surface of the spheroidized toner particles, by which the intended developer for electrostatic charge image is obtd. The hydrophobic treatment is accomplished further effectively if a coupling agent (e.g., isopropyl isostearitc titanate, silane coupling agent) is added in addition to the hydrophobic agent to said agent. |
