US Patent No. 9,188,888

ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE, ELECTROPHOTOGRAPHIC APPARATUS AND METHOD OF MANUFACTURING THE ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER


Patent No. 9,188,888
Issue Date November 17,2015
Title Electrophotographic Photosensitive Member, Process Cartridge, Electrophotographic Apparatus And Method Of Manufacturing The Electrophotographic Photosensitive Member
Inventorship Atsushi Okuda, Yokohama (JP)
Shio Murai, Toride (JP)
Kazunori Noguchi, Suntou-gun (JP)
Harunobu Ogaki, Suntou-gun (JP)
Kazuhisa Shida, Kawasaki (JP)
Takashi Anezaki, Hiratsuka (JP)
Assignee CANON KABUSHIKI KAISHA, Tokyo (JP)

Claim of US Patent No. 9,188,888

1. An electrophotographic photosensitive member, comprising:
a support,
a charge-generating layer which is provided on the support and comprises a charge-generating substance, and
a charge-transporting layer which is provided on the charge-generating layer and is a surface layer of the electrophotographic
photosensitive member;

wherein the charge-transporting layer has a matrix-domain structure having:
a domain which comprises the constituent ?, and
a matrix which comprises the constituent ? and a charge-transporting substance;
wherein the constituent ? is a polycarbonate resin A having a repeating structural unit represented by the following formula
(A), a repeating structural unit represented by the following formula (B) and a repeating structural unit represented by the
following formula (C),

the content of a siloxane moiety in the polycarbonate resin A is not less than 5% by mass and not more than 40% by mass relative
to the total mass of the polycarbonate resin A, the content of the repeating the structural unit represented by the formula
(B) is not less than 10% by mass and not more than 30% by mass relative to the total mass of the polycarbonate resin A, and
the content of the repeating the structural unit represented by the formula (C) is not less than 25% by mass and less than
85% by mass relative to the total mass of the polycarbonate resin A;


wherein, in the formula (A),
“n” represents number of repetitions of a structure within the bracket, an average of “n” in the polycarbonate resin A ranges
from 20 to 60;


wherein, in the formula (B),
Y represents an oxygen atom or a sulfur atom, and
R1 and R2 each independently represents a hydrogen atom, or a methyl group;


wherein the constituent ? is a polycarbonate resin D having a repeating structural unit represented by the following formula
(D)