| 摘要 |
PURPOSE:To improve a toner in triboelectric performance and to obtain a sharp image by specifying the contents of gamma-Fe2O3 and colloidal silica in the toner. CONSTITUTION:A toner contains gamma-Fe2O3 and colloidal silica in amts. of >=80wt% and 0.02-5wt% of the total content of a magnetic material, respectively. The toner has 0.5-20muQ/g triboelectrifiable absolute amt., 50-250Oe coercive force when a 10kOe external magnetic field is impressed, 15-40emu/g saturation magnetization, and 1.5-20emu/g residual magnetization. The toner can be spread in a thin layer more stably and more uniformly on the surface of a toner carrying body and a superior image is obtained by adding the colloidal silica to said magnetic toner in an amt. of 0.02-5wt% of the toner. |
