Electrophotographic photosensitive member, and electrophotographic apparatus and device unit employing the same

An electrophotographic apparatus, comprising an electrophotographic photosensitive member, an image-forming means for forming an electrostatic latent image, a developing means for developing the formed latent image, and a transferring means for transferring the developed image to an image-receiving material;

• said electrophotographic photosensitive member comprising an electroconductive support and a photosensitive layer formed thereon:
• the surface layer of the electrophotographic photosensitive member containing a first copolymer having a first construction unit represented by Formula (1) and a second construction unit represented by Formula (2), and a second copolymer having a third construction unit represented by Formula (3) and a fourth construction unit represented by Formula (4):
• ##STR50## wherein A is a group of alkylidene, arylene, arylenedialkylidene, --O--, --S--, --CO--, --SO--, or --SO.sub.2 --, and R.sub.1-1 to R.sub.1-8 are independently a hydrogen atom, an alkyl group, an aryl group, or a halogen atom;
• ##STR51## wherein R.sub.2-1 is an alkylene group or an alkylidene group, and R.sub.2-2 to R.sub.2-5 are independently a hydrogen atom, an alkyl group, or an aryl group, and n is an integer of 1 to 200;
• ##STR52## wherein R.sub.3-1 to R.sub.3-8 are independently a hydrogen atom, an alkyl group, an aryl group, or a halogen atom;
• ##STR53## wherein B is an alkylidene group, an arylene group, and an arylenedialkylidene group, and R.sub.4-1 to R.sub.4-8 are independently a hydrogen atom, an alkyl group, an aryl group, or a halogen atom.

A device unit, comprising an electrophotographic photosensitive member, and at least one means selected from the group consisting of a charging means, a developing means, and a cleaning means;

• said electrophotographic photosensitive member comprising an electroconductive support and a photosensitive layer formed thereon:
• the surface layer of the electrophotographic photosensitive member containing a first copolymer having a first construction unit represented by Formula (1) and a second construction unit represented by Formula (2), and a second copolymer having a third construction unit represented by Formula (3) and a fourth construction unit represented by Formula (4):
• ##STR54## wherein A is a group of alkylidene, arylene, arylenedialkylidene, --O--, --S--, --CO--, --SO--, or --SO.sub.2 --, and R.sub.1-1 to R.sub.1-8 are independently a hydrogen atom, an alkyl group, an aryl group, or a halogen atom;
• ##STR55## wherein R.sub.2-1 is an alkylene group or an alkylidiene group, and R.sub.2-2 to R.sub.2-5 are independently a hydrogen atom, an alkyl group, or an aryl group, and n is an integer of 1 to 200;
• ##STR56## wherein R.sub.3-1 to R.sub.3-8 are independently a hydrogen atom, an alkyl group, an aryl group or a halogen atom;
• ##STR57## wherein B is an alkylidene group, an arylene group, and an arylenedialkylidene group, and R.sub.4-1 to R.sub.4-8 are independently a hydrogen atom, an alkyl group, an aryl group, or a halogen atom;
• and said unit supporting integrally the electrophotographic photosensitive member and said at least one of the charging means, the developing means, and the cleaning means, and being removable from the main body of an electrophotographic apparatus.