| 摘要 |
PROBLEM TO BE SOLVED: To obtain a toner for developing an electrostatic charge image not contaminating a developing sleeve and an electrifying member, excellent in transferability and giving a stable image even at the time of repetitive use. SOLUTION: When dispersion of this toner is irradiated with 20 kHz, 50 W/10 cm<2> ultrasonic waves for 5 min, the measured value (C1 ) of particles of 0.6-2.0 μm particle diameter measured with a flow particle image analyzer is 3-50% by number. When the dispersion is irradiated with 20 kHz, 50 W/10 cm<2> ultrasonic waves for 1 min, the measured value (C2 ) of particles of 0.6-2.0μm particle diameter measured with the analyzer is 2-40% by number. Value (C) for (C1 /C2 )×100 is 105-150. The shape factor SF-1 of the toner particles is 100-160, the shape factor SF-2 of them is 100-140 and the wt. average particle diameter of them is 4-10 μm. |
