| 摘要 |
PURPOSE:To obtain a toner hardly causing reverse electrostatic charging or noncharging by dispersing carbon black and an electrostatic charging controller in an oil phase of a radical polymerizable monomer, suspension-polymerizing the oil phase in water in the presence of PVA and nitrating the PVA. CONSTITUTION:Carbon black and the powdery electrostatic charging controller are dispersed in the oil phase of the radical polymerizable monomer and the oil phase is suspension-polymerized in a water phase contg. PVA as a suspension stabilizer to obtain a spherical polymer. This polymer is treated with an aq. nitrating agent to nitrate the PVA and the resulting spherical polymer is recovered. The radical polymerizable monomer may be styrene, o-methylstyrene or m-methylstyrene. The toner hardly causing reverse electrostatic charging and noncharging at the time of electrostatic copying can be obtd. |
