Patent ID: 11960240
Assignee: CANON KABUSHIKI KAISHA
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 1:
2. The electrophotographic photosensitive member according to claim 1, which has a charge retainability is 9.5 or more, wherein
charge retainability is determined by procedures 1 to 4:
procedure 1 applies a voltage to a surface of the electrophotographic photosensitive member from one direction while rotating the electrophotographic photosensitive member at a rotational speed of 30 rpm under an environment of a temperature of 23° C. and a humidity of 50% RH, the voltage being a rectangular wave voltage having a frequency of 1 Hz, a Voffset of −450 V, and a Vpp of 500 V,
procedure 2 measures a potential on the surface of the electrophotographic photosensitive member at a position at which a portion to which the voltage is applied to the surface of the electrophotographic photosensitive member is rotated for 0.30 seconds at a measurement interval of 100 μs for a predetermined time within the range from 10 to 20 seconds,
procedure 3 plots the values obtained by the measurement using μs as a unit of a horizontal axis and V as a unit of a vertical axis, and a slope of each of a regression line derived from previous 25 measurement points and a regression line derived from latter 25 measurement points is determined at each measurement point, and
procedure 4 calculates charge retainability by averaging absolute values of a maximum value and a minimum value of the obtained slopes.