US 12,443,118 B2
Electrophotographic photosensitive member, process cartridge, and image forming apparatus
Tomofumi Shimizu, Osaka (JP); and Makoto Shishido, Osaka (JP)
Assigned to KYOCERA Document Solutions Inc., Osaka (JP)
Filed by KYOCERA Document Solutions Inc., Osaka (JP)
Filed on May 25, 2022, as Appl. No. 17/664,997.
Claims priority of application No. 2021-088352 (JP), filed on May 26, 2021.
Prior Publication US 2022/0397835 A1, Dec. 15, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. G03G 5/05 (2006.01); G03G 5/06 (2006.01); G03G 21/18 (2006.01)
CPC G03G 5/0567 (2013.01) [G03G 5/0609 (2013.01); G03G 5/0631 (2013.01); G03G 5/0648 (2013.01); G03G 21/1814 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An electrophotographic photosensitive member comprising:
a conductive substrate; and
a photosensitive layer, wherein
the photosensitive layer is a single layer,
the photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin,
the binder resin includes a polyarylate resin,
the polyarylate resin includes repeating units represented by formulas (1), (2), (3), and (4), and
a percentage of the number of repeats of the repeating unit represented by the formula (3) relative to a total of the number of repeats of the repeating unit represented by the formula (1) and the number of repeats of the repeating unit represented by the formula (3) is greater than 0% and less than 20%,
the repeating unit represented by the formula (1) is adjacent and bonded to the repeating unit represented by the formula (2), and/or the repeating unit represented by the formula (1) is adjacent and bonded to the repeating unit represented by the formula (4),
the repeating unit represented by the formula (3) is adjacent and bonded to the repeating unit represented by the formula (2), and/or the repeating unit represented by the formula (3) is adjacent and bonded to the repeating unit represented by the formula (4),

OG Complex Work Unit Chemistry
wherein the formula (1), R1 and R2 each represent, independently of one another, a hydrogen atom or a methyl group and X represents a divalent group represented by formula (X1) or (X2), and
in the formula (2), W represents a divalent group represented by formula (W1) or (W2),

OG Complex Work Unit Chemistry
wherein the formula (X1), t represents an integer of at least 1 and no greater than 3 and represents a bond, and
in the formula (X2), R3 and R4 each represent a hydrogen atom or an alkyl group with a carbon number of at least 1 and no greater than 4, R3 and R4 represent chemical groups different from each other, and * represents a bond,

OG Complex Work Unit Chemistry
wherein the formulas (W1) and (W2), * represents a bond.