| 摘要 |
PURPOSE:To obviate the change in characteristics even after long-term preservation by specifying the viscosity of coloring agent-contg. resin particles, forming a flowability improving agent of an inorg. oxide subjected to a hydrophobic property imparting treatment and forming fine spherical resin particles so as to have the surface free energy and Vickers hardness smaller than the surface free energy and Vickers hardness of the coloring agent-contg. resin particles. CONSTITUTION:The developer contains the coloring agent-contg. resin particles, the flowability improving agent which is smaller in grain size than the coloring agent-contg. resin particles and the fine spherical resin particles which are smaller in grain size than the coloring agent-contg. resin particles and larger than the flowability improving agent. The apparatus viscosities at 100 deg.C and 90 deg.c of the coloring agent-contg. resin particles are in 10<4>-5X10<5> poise and 5X10<5>-5X10<6> poise ranges. The flowability improving agent is the inorg. oxide subjected to the hydrophobic property imparting treatment. The fine spherical resin particles are smaller in the surface free energy and Vickers hardness than the coloring agent-contg. resin particles. The change in the characteristics is thereby obviated even if the developer is rested or preserved for a long period of time. Splashing is decreased with the easy-to-carry developer. |
