Electrophotographic photoreceptor, process cartridge, and image forming apparatus

Patent metadata

Field	Value
Publication number	US-12596311-B2
Application number	US-202318180810-A
Country	US
Kind code	B2
Filing date	Mar 8, 2023
Priority date	Mar 11, 2022
Publication date	Apr 7, 2026
Grant date	Apr 7, 2026

Abstract

An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer in this order, in which the charge transport layer contains at least one resin selected from a polyester resin or a polycarbonate resin, and in a case where a Martens hardness and an indentation hardness, which are acquired by an indentation test performed on the charge transport layer to a depth of 0.5 μm, are respectively defined as HM (N/mm 2 ) and nIT (N/mm 2 ), Relational Equation (0) is satisfied, an elastic deformation modulus is 45% or greater and 70% or less, and a tensile elastic modulus of the charge transport layer is 2,300 MPa or greater and 5,000 MPa or less,

n IT= a ×HM− b ( a =2±0.2, b =100±20).  (0)

First claim

What is claimed is:

1 . An electrophotographic photoreceptor comprising:
a conductive substrate; and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer in this order, wherein the charge transport layer contains a polyester resin, wherein the polyester resin having a dicarboxylic acid unit (A) represented by Formula (A) and a diol unit (B) including at least one selected from the group consisting of a diol unit (B1) represented by Formula (B1), a diol unit (B2) represented by Formula (B2), a diol unit (B3) represented by Formula (B3), a diol unit (B5) represented by Formula (B5), a diol unit (B6) represented by Formula (B6), a diol unit (B7) represented by Formula (B7), and a diol unit (B8) represented by Formula (B8),

in Formula (A), X represents an organic group,
in Formula (B1), Rb 101 represents a branched alkyl group having 4 or more and 20 or less carbon atoms, Rb 201 represents a hydrogen atom or an alkyl group having 1 or more and 3 or less carbon atoms, and Rb 401 , Rb 501 , Rb 801 , and Rb 901 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom,
in Formula (B2), Rb 102 represents a linear alkyl group having 4 or more and 20 or less carbon atoms, Rb 202 represents a hydrogen atom or an alkyl group having 1 or more and 3 or less carbon atoms, and Rb 402 , Rb 502 , Rb 802 , and Rb 902 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom,
in Formula (B3), Rb 113 and Rb 213 each independently represent a hydrogen atom, a linear alkyl group having 1 or more and 3 or less carbon atoms, an alkoxy group having 1 or more and 4 or less carbon atoms, or a halogen atom, d represents an integer of 7 or greater and 15 or less, and Rb 403 Rb 503 Rb 803 , and Rb 903 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom,
in Formula (B5), Ar 105 represents an aryl group having 6 or more and 12 or less carbon atoms or an aralkyl group having 7 or more and 20 or less carbon atoms, Rb 20 ) represents a hydrogen atom or an alkyl group having 1 or more and 3 or less carbon atoms, and Rb 405 , Rb 505 Rb 805 , and Rb 905 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom,
in Formula (B6), Rb 116 and Rb 216 each independently represent a hydrogen atom, a linear alkyl group having 1 or more and 3 or less carbon atoms, an alkoxy group having 1 or more and 4 or less carbon atoms, or a halogen atom, e represents an integer of 4 or greater and 6 or less, and Rb 406 , Rb 506 Rb 806 , and Rb 906 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom,
in Formula (B7), Rb 407 , Rb 507 , Rb 807 , and Rb 907 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom,
in Formula (B8), Rb 408 , Rb 508 , Rb 808 , and Rb 908 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom, and
in a case where a Martens hardness and an indentation hardness, which are acquired by an indentation test performed on the charge transport layer to a depth of 0.5 um, are respectively defined as HM (N/mm 2 ) and nIT (N/mm 2 ), Relational Equation (0) is satisfied, an elastic deformation modulus of the charge transport layer is 45% or greater and 70% or less, and a tensile elastic modulus of the charge transport layer is 2,300 MPa or greater and 5,000 MPa or less,
n IT= a ×HM− b , wherein a= 2±0.2, b= 100±20.  (0)

2 . An electrophotographic photoreceptor comprising:
a conductive support; and a single layer type photosensitive layer disposed on the conductive support, wherein the single layer type photosensitive layer contains a polyester resin, the polyester resin having a dicarboxylic acid unit (A) represented by Formula (A) and a diol unit (B) including at least one selected from the group consisting of a diol unit (B1) represented by Formula (B1), a diol unit (B2) represented by Formula (B2), a diol unit (B3) represented by Formula (B3), a diol unit (B5) represented by Formula (B5), a diol unit (B6) represented by Formula (B6), a diol unit (B7) represented by Formula (B7), and a diol unit (B8) represented by Formula (B8),

in Formula (A), X represents an organic group,
in Formula (B1), Rb 101 represents a branched alkyl group having 4 or more and 20 or less carbon atoms, Rb 201 represents a hydrogen atom or an alkyl group having 1 or more and 3 or less carbon atoms, and Rb 401 , Rb 501 , Rb 801 , and Rb 901 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom,
in Formula (B2), Rb 102 represents a linear alkyl group having 4 or more and 20 or less carbon atoms, Rb 202 represents a hydrogen atom or an alkyl group having 1 or more and 3 or less carbon atoms, and Rb 402 , Rb 502 Rb 802 , and Rb 902 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom,
in Formula (B3), Rb 113 and Rb 213 each independently represent a hydrogen atom, a linear alkyl group having 1 or more and 3 or less carbon atoms, an alkoxy group having 1 or more and 4 or less carbon atoms, or a halogen atom, d represents an integer of 7 or greater and 15 or less, and Rb 403 , Rb 503 Rb 803 , and Rb 903 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom,
in Formula (B5), Ar 105 represents an aryl group having 6 or more and 12 or less carbon atoms or an aralkyl group having 7 or more and 20 or less carbon atoms, Rb 205 represents a hydrogen atom or an alkyl group having 1 or more and 3 or less carbon atoms, and Rb 405 , Rb 505 , Rb 805 , and Rb 905 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom,
in Formula (B6), Rb 116 and Rb 216 each independently represent a hydrogen atom, a linear alkyl group having 1 or more and 3 or less carbon atoms, an alkoxy group having 1 or more and 4 or less carbon atoms, or a halogen atom, e represents an integer of 4 or greater and 6 or less, and Rb 406 , Rb 506 , Rb 806 , and Rb 906 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group having 1 or more and 6 or less carbon atoms, or a halogen atom,
in Formula (B7), Rb 407 , Rb 507 , Rb 807 , and Rb 907 each independently represent a hydrogen atom, an alkyl group having 1 or more and 4 or less carbon atoms, an alkoxy group

Assignees

• Fujifilm Business Innovation Corp

Inventors

• Kobayashi Hiroko
• Sasaki Tomoya
• Hashimoto Kohei
• Fujii Ryosuke
• Okazaki Yuto
• Narita Kosuke

Classifications

• G03G5/07

  Polymeric photoconductive materials · CPC title

• G03G15/0233

  Structure, details of the charging member, e.g. chemical composition, surface properties · CPC title

• G03G5/0596

  Macromolecular compounds characterised by their physical properties · CPC title

• G03G5/0592

  Macromolecular compounds characterised by their structure or by their chemical properties, e.g. block polymers, reticulated polymers, molecular weight, acidity · CPC title

• G03G15/0121 Primary

  for developing · CPC title