Polyarylate resin and electrophotographic photosensitive member

Patent metadata

Field	Value
Publication number	US-12360468-B2
Application number	US-202217701330-A
Country	US
Kind code	B2
Filing date	Mar 22, 2022
Priority date	Mar 24, 2021
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

A polyarylate resin includes repeating units (1), (2), and (4).The polyarylate resin further includes a repeating unit (3) and a percentage of the number of repeats of the repeating unit (3) relative to the total number of repeats of each of the repeating units (1) and (3) is greater than 0% and less than 50%. Alternatively, the polyarylate resin does not include the repeating unit (3).

First claim

What is claimed is:

1. A polyarylate resin, comprising repeating units represented by formulas (1), (2), and (4), wherein
the polyarylate resin does not comprise the repeating unit represented by the formula (3),
the repeating unit represented by the formula (1) includes the repeating unit represented by the formula (1-1), and
the repeating unit represented by the formula (1) further includes a repeating unit represented by formula (1-4)

where in the formula (1), R 1 and R 2 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),
in the formula (3), R 5 and R 6 each represent, independently of one another, a hydrogen atom or a methyl group and W represents a single bond or an oxygen atom,

in 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), R 3 and R 4 each represent, independently of one another, a hydrogen atom or an alkyl group with a carbon number of at least 1 and no greater than 4 and * represents a bond

2. An electrophotographic photosensitive member comprising a conductive substrate and a photosensitive layer, wherein
the photosensitive layer contains a charge generating material, a hole transport material, and a binder resin, and
the binder resin includes the polyarylate resin according to claim 1 .

3. The electrophotographic photosensitive member according to claim 2 , wherein
the hole transport material includes a compound represented by formula (20), (21), or (22),

where in the formula (20): R 21 and R 22 each represent, independently of one another, a phenyl group, an alkyl group with a carbon number of at least 1 and no greater than 8, or an alkoxy group with a carbon number of at least 1 and no greater than 8; R 23 to R 29 each represent, independently of one another, a hydrogen atom, an alkyl group with a carbon number of at least 1 and no greater than 8, a phenyl group optionally substituted with an alkyl group with a carbon number of at least 1 and no greater than 8, or an alkoxy group with a carbon number of at least 1 and no greater than 8; any adjacent two of chemical groups R 25 to R 29 may be bonded to form a ring; and a1 and a2 each represent, independently of one another, an integer of at least 0 and no greater than 5,
in the formula (21): R 31 to R 36 each represent, independently of one another, a phenyl group or an alkyl group with a carbon number of at least 1 and no greater than 8; R 37 and R 38 each represent, independently of one another, a hydrogen atom, a phenyl group, or an alkyl group with a carbon number of at least 1 and no greater than 8; b1, b2, b3, and b4 each represent, independently of one another, an integer of at least 0 and no greater than 5; b5 and b6 each represent, independently of one another, an integer of at least 0 and no greater than 4; and d and e each represent, independently of one another, 0 or 1, and
in the formula (22): R 41 to R 46 each represent, independently of one another, a phenyl group, an alkyl group with a carbon number of at least 1 and no greater than 8, or an alkoxy group with a carbon number of at least 1 and no greater than 8; f1, f2, f4, and f5 each represent, independently of one another, an integer of at least 0 and no greater than 5; and f3 and f6 each represent, independently of one another, an integer of at least 0 and no greater than 4.

4. The electrophotographic photosensitive member according to claim 2 , wherein
the hole transport material includes a compound represented by formula (HTM-1), (HTM-2), (HTM-3), (HTM-4), (HTM-5), or (HTM-6)

5. The electrophotographic photosensitive member according to claim 2 , wherein
the photosensitive layer includes a charge generating layer containing the charge generating material and a charge transport layer containing the hole transport material and the binder resin, and
the charge transport layer is a single layer serving as an outermost layer.

Assignees

• Kyocera Document Solutions Inc

Inventors

• Azuma Jun
• Maruo Keiji
• Kitaguchi Kenji

Classifications

• C08G63/193

  containing two or more aromatic rings · CPC title

• G03G5/047

  characterised by the charge-generation layers or charge transport layers {(G03G5/0433 and G03G5/0436 take precedence)} · CPC title

• C08G63/189

  containing a naphthalene ring · CPC title

• C08G63/185

  containing two or more aromatic rings · CPC title

• G03G5/056 Primary

  Polyesters · CPC title