Electrophotographic photosensitive member, process cartridge, and image forming apparatus

Patent metadata

Field	Value
Publication number	US-10359713-B2
Application number	US-201815948825-A
Country	US
Kind code	B2
Filing date	Apr 9, 2018
Priority date	Apr 12, 2017
Publication date	Jul 23, 2019
Grant date	Jul 23, 2019

Abstract

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer having a single-layer structure. The photosensitive layer contains a charge generating material, an electron transport material, and a binder resin. The electron transport material includes a compound having a halogen atom and represented by a general formula (1), (2), (3), (4), or (5). The binder resin includes a polyarylate resin. The polyarylate resin includes at least one type of repeating unit each represented by general formula (11), at least one type of repeating unit each represented by general formula (12), and a terminal group represented by general formula (13). In general formula (13), R f represents a chain aliphatic group substituted by at least one fluoro group. A charge of calcium carbonate charged by friction between the photosensitive layer and the calcium carbonate is at least +8.0 μC/g.

First claim

What is claimed is:

1. An electrophotographic photosensitive member comprising a conductive substrate and a photosensitive layer having a single-layer structure, wherein
the photosensitive layer contains a charge generating material, an electron transport material, and a binder resin,
the electron transport material includes a compound having a halogen atom and represented by a general formula (1), (2), (3), (4), or (5),
the binder resin includes a polyarylate resin,
the polyarylate resin includes at least one type of repeating unit each represented by a general formula (11), at least one type of repeating unit each represented by a general formula (12), and a terminal group represented by a general formula (13),
a charge of calcium carbonate charged by friction between the photosensitive layer and the calcium carbonate is at least +8.0 μC/g,
the charge of the calcium carbonate is measured by first through fourth particulars,
in the first particular, two photosensitive layers are prepared, each of the two photosensitive layers being the photosensitive layer, one of the two photosensitive layers being a first photosensitive layer, the other of the two photosensitive layers being a second photosensitive layer, the first and second photosensitive layers being in a circular shape of a diameter of 3 cm,
in the second particular, 0.007 g of the calcium carbonate is applied onto the first photosensitive layer to form a calcium carbonate layer constituted by the calcium carbonate, and the second photosensitive layer is superposed on the calcium carbonate layer,
in the third particular, the first photosensitive layer is rotated at a rotational speed of 60 rpm for 60 seconds while the second photosensitive layer is kept stationary in an environment at a temperature of 23° C. and a relative humidity of 50% to charge the calcium carbonate contained in the calcium carbonate layer through friction between the calcium carbonate and each of the first photosensitive layer and the second photosensitive layer, and
in the fourth particular, the charged calcium carbonate is sucked using a charge measuring device, a total electric charge Q and a mass M of the sucked calcium carbonate are measured using the charge measuring device, and the charge of the calcium carbonate is calculated according to an expression Q/M,

where in the general formula (1), R 1 represents: an alkyl group having a carbon number of at least 1 and no greater than 8 and substituted by at least one halogen atom; a cycloalkyl group having a carbon number of at least 3 and no greater than 10 and substituted by at least one halogen atom; an aryl group having a carbon number of at least 6 and no greater than 14, substituted by at least one halogen atom, and optionally substituted by an alkyl group having a carbon number of at least 1 and no greater than 6; a heterocyclic group substituted by at least one halogen atom; or an aralkyl group having a carbon number of at least 7 and no greater than 20 and substituted by at least one halogen atom,
in the general formula (2), R 21 and R 22 each represent, independently of each other, an alkyl group having a carbon number of at least 1 and no greater than 6, and R 23 represents a halogen atom,
in the general formula (3), R 31 , R 32 , R 33 , R 34 , R 35 , and R 36 each represent, independently of one another: a halogen atom; a hydrogen atom; an alkyl group having a carbon number of at least 1 and no greater than 6 and optionally substituted by at least one halogen atom; an alkenyl group having a carbon number of at least 2 and no greater than 6 and optionally substituted by at least one halogen atom; an alkoxy group having a carbon number of at least 1 and no greater than 6 and optionally substituted by at least one halogen atom; an aralkyl group having a carbon number of at least 7 and no greater than 20 and optionally substituted by at least one halogen atom; an aryl group having a carbon number of at least 6 and no greater than 14 and optionally substituted by at least one halogen atom; a heterocyclic group optionally substituted by at least one halogen atom; a cyano group; a nitro group; a hydroxyl group; a carboxyl group; or an amino group, with the proviso that at least one of R 31 , R 32 , R 33 , R 34 , R 35 , and R 36 represents a halogen atom or a chemical group substituted by at least one halogen atom, X represents an oxygen atom, a sulfur atom, or ═C(CN) 2 , and Y represents an oxygen atom or a sulfur atom,
in the general formula (4), R 41 and R 42 each represent, independently of each other: an alkyl group having a carbon number of at least 1 and no greater than 8 and substituted by at least one halogen atom; an aryl group having a carbon number of at least 6 and no greater than 14, substituted by at least one halogen atom, and optionally substituted by an alkyl group having a carbon number of at least 1 and no greater than 6; an aralkyl group having a carbon number of at least 7 and no greater than 20 and substituted by at least one halogen atom; or a cycloalkyl group having a carbon number of at least 3 and no greater than 20 and substituted by at least one halogen atom, R 43 and R 44 each represent, independently of each other, an alkyl group having a carbon number of at least 1 and no greater than 6, an aryl group having a carbon number of at least 6 and no greater than 14, a cycloalkyl group having a carbon number of at least 3 and no greater than 20, or a heterocyclic group, and b1 and b2 each represent, independently of each other, an integer of at least 0 and no greater than 4,
in the general formula (5), R 51 and R 52 each represent, independently of each other: an aryl group having a carbon number of at least 6 and no greater than 14 and optionally substituted by at least one halogen atom; an aryl group having a carbon number of at least 6 and no greater than 14, substituted by at least one alkyl group having a carbon number of at least 1 and no greater than 6, and optionally substituted by at least one halogen atom; an aryl group having a carbon number of at least 6 and no greater than 14, substituted by at least one benzoyl group, and optionally substituted by at least one halogen atom; an aralkyl group having a carbon number of at least 7 and no greater than 20 and optionally substituted by at least one halogen atom; an alkyl group having a carbon number of at least 1 and no greater than 8 and optionally substituted by at least one halogen atom; or a cycloalkyl group having a carbon number of at least 3 and no greater than 10 and optionally substituted by at least one halogen atom, with the proviso that at least one of R 51 and R 52 represents a chemical group substituted by at least one halogen atom,

in the general formula (11), R 101 , R 102 , R 103 , and R 104 each represent, independently of each other, a hydrogen atom or a methyl group, R 105 and R 106 each represent, independently of each other, a hydrogen atom or an alkyl group having a carbon number of at least 1 and no greater than 4, and R 105 and R 106 may bond together to represent a cycloalkylidene group having a carbon number of at least 5 and no greater than 7,
in the general formula (12), Z 1 represents a divalent group represented by a chemical formula (12A), (12B), (12C), or (12D), with the proviso that when the polyarylate resin includes only one type of repeating unit represented by the general formula (12), Z 1 does not represent a divalent group represented by the chemical formula (12D), and
in the general formula (13), R f represents a chain aliphatic group substituted by at least one fluoro group

Assignees

• Kyocera Document Solutions Inc

Inventors

• Shimizu Tomofumi
• Azuma Jun

Classifications

• G03G5/0653

  containing five relevant rings · CPC title

• G03G5/0631

  containing two hetero atoms · CPC title

• G03G5/0609

  containing oxygen · CPC title

• G03G5/0607

  containing at least one non-six-membered ring · CPC title

• G03G5/0564

  Polycarbonates · CPC title