| 摘要 |
PURPOSE:To prevent fogging and voiding by incorporating inorg. fine powder surface-treated with a treating agent having a positive polar group and a treating agent having a negative polar group into a toner. CONSTITUTION:When the surfaces of fine SiO2 particles as inorg. fine particles are treated with a fluorine-contg. coupling agent and an amino coupling agent, hydroxyl groups on the surfaces of the SiO2 particles react reversibly with silanol groups, etc., derived from the coupling agents to introduce F atom-contg. groups and N atom-contg. groups into the surfaces of the particles. The surface- treated inorg. fine particles for a developer having negatively chargeable polar groups and positively chargeable polar groups bonded to the surfaces are incorporated into a toner for developing an electrostatic charge image. A toner having a high electrostatic charge level, satisfactory kick-off performance of electrostatic charge, superior printing resistance and environmental stability of the electrostatically charged state is obtd. By using this toner, ground fogging and scattering around letters are prevented and a superior image is formed. |
