Patent ID: 8288065

Claim:
An organic photoreceptor comprising a charge generation layer and a charge transport layer provided on a conductive substrate, wherein the substrate has a ten-point surface roughness Rz of the substrate of 0.2 Î¼m or less, the charge generation layer comprises a charge generation material comprising particles of a condensed polycyclic pigment, having an average major axis length of 500 nm or less, an average aspect ratio of 2.5 to 5.0, and an aspect ratio variation coefficient of 16% or less, and quantum efficiency Î¦ of the photoreceptor is not less than 0.5, the quantum efficiency Î¦ being defined by a Formula of Î¦=Î”Q/(n 0 Ã—e), wherein Î”Q is reduced amount of charge [C] in case that light having light amount predetermined so as to make the electric field E becomes â…” times of initial electric field after unit time (1 sec.) is exposed to the organic photoreceptor under condition of the initial electric field E 0 =2.5Ã—10 5 [VÂ·cm âˆ’1 ], and n 0 is a number of incident photons per unit area (1 cm 2 ) and in unit time (1 sec.) in terms of [cm âˆ’2 Â·s âˆ’1 ] in case that light having light amount predetermined so as to make the electric field E becomes â…” times of initial electric field after unit time (1 sec.) is exposed to the organic photoreceptor under condition of the initial electric field E 0 =2.5Ã—10 5 [VÂ·cm âˆ’1 ], and e is an elementary electric charge 1.3Ã—10 âˆ’19 [C], wherein the condensed polycyclic pigment is represented by Formula (1): wherein n is an integer of 1-6.