1. Field of the Invention
The present invention relates to an electrophotographic photosensitive member, a process cartridge and an electrophotographic apparatus each having an electrophotographic photosensitive member.
2. Description of the Related Art
Since a semiconductor laser commonly used in an image exposure unit in the field of electrophotography has a long oscillation wavelength in the range of 650 to 820 nm, electrophotographic photosensitive members having high sensitivity to light in the long wavelength range are currently under development.
Phthalocyanine pigments used as a material for electrophotographic photosensitive members are effective as charge generation substances having high sensitivity to the light ranging to such a long wavelength region. Oxytitanium phthalocyanine and gallium phthalocyanine in particular have excellent sensitivity properties, and various crystal forms have been reported until now.
Although an electrophotographic photosensitive member using a phthalocyanine pigment has excellent sensitivity properties, a problem is that the generated photo carriers tend to remain in a photosensitive layer so as to act as a memory, easily causing potential variation such as ghosting.
Japanese Patent Application Laid-Open No. 2012-32781 discloses that the addition of a specific amine compound to a charge generation layer can reduce ghosting.
Japanese Patent Application Laid-Open No. 2007-182556 discloses that the use of a resin having a specific triphenylamine skeleton as a resin for a charge generation layer can improve dispersibility and optical sensitivity.
Various attempts have been made to improve electrophotographic photosensitive members as described above.
For further improvement in high-quality picture in recent years, it is desired to further prevent image degradation due to ghosting in various environments.
USPTO Backgrounds
USPTO Backgrounds