Electrophotographic photoreceptor, process cartridge, and image forming apparatus

A process cartridge comprising:

• an electrophotographic photoreceptor which comprises an electroconductive support;
• and
• a photosensitive layer on the electroconductive support, wherein
• the photosensitive layer having a dynamic hardness of from 20×109 to 150×109 N/m2 and an elastic deformation ratio of from 15 to 80%;
• the photosensitive layer comprises a phenol resin-containing layer on the farthest side of the potosensitive layer from the electrocondutice support, the phenol resin-containing layer comprising a phenol resin having a crosslinked structure and charge transporting property;
• the phenol resing is formed;
• a phenol derivative having a methylol group;
• and a charge transportin material having a reactive functional group;
• at least one selected from the group consisting of a charging unit charging the electrophotographic photoreceptor, a developing unit developing an electrostatic latent image formed on the electrophotographic photoreceptor with a toner to from a toner image, and a cleaning unit removing the toner remaining on a surface of the electrophotographic photoreceptor;
• the charge transporting material is represented by formula (IV):
• wherein F represents a n5-valent organic group having a positive hole transporting capability,
• T represents a divalent group,
• Y represents an oxygen atom or a sulfur atom,
• R4, R5 and R6 each independently represents a hydrogen atom or a monovalent organic group,
• R7 represents a monovalent organic group,
• m1 represents 0 or 1, and
• n5 represents an integer of from 1 to 4, provided that R6 and R7 may be bonded to form a heterocyclic ring containing Y as a hetero atom;
• the photosensitive layer comprises an undercoating layer on a side of the electroconductive support, the undercoating layer comprises a composite of an acceptive compound having an anthraquinone structure and metallic oxide fine particles, and
• a thickness of the undercoating layer is from 15 μm to 50 μm.

An image forming apparatus comprising:

• an electrophotographic photoreceptor which comprises an electroconductive support;
• and
• a photosensitive layer on the electroconductive support, wherein
• the photosensitive layer having a dynamic hardness of from 20×109 to 150×109 N/m2 and an elastic deformation ratio of from 15 to 80%;
• the photosensitive layer comprises a phenol resin-containing layer on the farthest side of the photosensitive layer from the electroconductive support, the phenol resin-containing layer comprising a phenol resin having a crosslinked structure and charge transporting property;
• the phenol resin is formed from:
• a phenol derivative having a methylol group;
• and a charge transporting material having a reactive functional group;
• and
• the charge transporting material is represented by formula (IV):
• wherein F represents a n5-valent organic group having a positive hole transporting capability,
• T represents a divalent group,
• Y represents an oxygen atom or a sulfur atom,
• R4, R5 and R6 each independently represents a hydrogen atom or a monovalent organic group, R7 represents a monovalent organic group,
• m1 represents 0 or 1, and
• n5 represents an integer of from 1 to 4, provided that R6 and R7 may be bonded to form a heterocyclic ring containing Y as a hetero atom;
• p1 the photosensitive layer comprises an undercoating layer on a side of the electroconductive support, the undercoating layer comprises a composite of an acceptive compound having an anthraquinone structure and metallic oxide fine particles;
• a charging unit charging the electrophotographic photoreceptor;
• an exposing unit forming an electrostatic latent image on the electrophotographic photoreceptor charged;
• a developing unit developing an electrostatic latent image with a toner to form a toner image;
• a transferring unit transferring the toner image from the electrophotographic photoreceptor to a transferring material, and
• a thickness of the undercoating layer is from 15 μm to 50 μm.