Electrophotographic photoconductor, and process cartridge and image forming apparatus using the same

An electrophotographic photoconductor comprising an electroconductive support and a photoconductive layer formed thereon, a surface top portion of said photoconductor comprising a high-molecular charge transport material which comprises a polycarbonate copolymer synthesized from:

• (a) a bisphenol monomer with an ionization potential of 6.0 eV or less, having a positive hole transporting function, and
• (c) a bisphenol monomer of formula (1):
• wherein R1 is a straight-chain or branched alkyl group having 2 to 18 carbon atoms;
• R2 is a hydrogen atom, a straight-chain or branched alkyl group having 1 to 18 carbon atoms, provided that the total number of carbon atoms of R1 and R2 is 3 or more;
• and R3, R4, R5, and R6 are each a hydrogen atom, a halogen atom, a straight-chain or branched alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 5 to 7 carbon atoms, or phenyl group.

A process cartridge which is freely detachable from an electrophotographic image forming apparatus, comprising an electrophotographic photoconductor, and at least one means selected from the group consisting of a charging means, an image exposure means, a developing means, an image transfer means, and a cleaning means,

• said electrophotographic photoconductor comprising an electroconductive support and a photoconductive layer formed thereon, a surface top portion of said photoconductor comprising a high-molecular charge transport material which comprises a polycarbonate copolymer synthesized from:
• (a) a bisphenol monomer with an ionization potential of 6.0 eV or less, having a positive hole transporting function, and
• (c) a bisphenol monomer of formula (1):
• wherein R1 is a straight-chain or branched alkyl group having 2 to 18 carbon atoms;
• R2 is a hydrogen atom, a straight-chain or branched alkyl group having 1 to 18 carbon atoms, provided that the total number of carbon atoms of R1 and R2 is 3 or more;
• and R3, R4, R5, and R6 are each a hydrogen atom, a halogen atom, a straight-chain or branched alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 5 to 7 carbon atoms, or phenyl group.

An electrophotographic image forming apparatus comprising an electrophotographic photoconductor comprising an electroconductive support and a photoconductive layer formed thereon, a surface top portion of said photoconductor comprising a high-molecular charge transport material which comprises a polycarbonate copolymer synthesized from:

• (a) a bisphenol monomer with an ionization potential of 6.0 eV or less, having a positive hole transporting function, and
• (c) a bisphenol monomer of formula (1);
• wherein R1 is a straight-chain or branched alkyl group having 2 to 18 carbon atoms;
• R2 is a hydrogen atom, a straight-chain or branched alkyl group having 1 to 18 carbon atoms, provided that the total number of carbon atoms of R1 and R2 is 3 or more;
• and R3, R4, R5, and R6 are each a hydrogen atom, a halogen atom, a straight-chain or branched alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 5 to 7 carbon atoms, or phenyl group.

An electrophotographic image forming apparatus comprising a process cartridge which is freely detachable from said image forming apparatus, and comprises:

• at least one means selected from the group consisting of a charging means, an image exposure means, a developing means, an image transfer means, and a cleaning means, and
• an electrophotographic photoconductor comprising an electroconductive support and a photoconductive layer formed thereon, a surface top portion of said photoconductor comprising a high-molecular charge transport material which comprises a polycarbonate copolymer synthesized from (a) a bisphenol monomer with an ionization potential of 6.0 eV or less, having a positive hole transporting function, and (c) a bisphenol monomer of formula (1):
• wherein R1 is a straight-chain or branched alkyl group having 2 to 18 carbon atoms;
• R2 is a hydrogen atom, a straight-chain or branched alkyl group having 1 to 18 carbon atoms, provided that the total number of carbon atoms of R1 and R2 is 3 or more;
• and R3, R4, R5, and R6 are each a hydrogen atom, a halogen atom, a straight-chain or branched alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 5 to 7 carbon atoms, or phenyl group.