Kyocera Document Solutions Inc.

Kensuke Okawa

Jun Azuma

Akihiko Ogata

Tomofumi Shimizu

Seiki Hasunuma

Hideki Okada

Keiji Maruo

Kenji Kitaguchi

Takahiro Oki

Fumio Sugai

Kensuke Kojima

Junichiro Otsubo

Makoto Shishido

Eiji Morimoto

An electrophotographic photosensitive member () includes a conductive substrate () and a photosensitive layer () disposed directly or indirectly on the conductive substrate (). The photosensitive layer () has a charge generating layer () and a charge transport layer () disposed in order from the conductive substrate (). The charge generating layer () contains a charge generating material. The charge transport layer () contains a charge transport material, a binder resin, and a pigment that absorbs light having an irradiation wavelength. The binder resin includes a polyarylate resin including a repeating unit represented by general formula (1):   

Electrophotographic photosensitive member and image forming apparatus

An electrophotographic photosensitive member includes a photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, and a binder resin. The binder resin contains a polyarylate resin represented by general formula (1). In general formula (1), r and s each represent an integer of at least 0 and no greater than 49 and t and u represents an integer of at least 1 and no greater than 50. Furthermore, r+s+t+u=100 and r+t=s+u. X and Y each represent, independently of one another, a divalent group represented by chemical formula (1-1), (1-2), (1-3), or (1-4). 

Polyarylate resin and electrophotographic photosensitive member

A polyarylate resin includes at least one type of repeating unit represented by a general formula (1), at least one type of repeating unit represented by a general formula (2), and a terminal group represented by a general formula (3). R, R, R, and Reach represent, independently of one another, a hydrogen atom or a methyl group. Rand Reach represent, independently of each other, a hydrogen atom or a Calkyl group. Rand Rmay bond together to represent a Ccycloalkylidene group. Xrepresents a divalent group represented by a chemical formula (2A), (2B), (2C), or (2D) with the proviso that when only one type of repeating unit represented by the general formula (2) is included, Xdoes not represent a divalent group represented by the chemical formula (2D). Rrepresents a chain aliphatic group having at least one fluoro group. 

A polyarylate resin is represented by general formula (1) shown below. In general formula (1), Rand Reach represent, independently of one another, a hydrogen atom or a methyl group. r and s each represent an integer of at least 0 and no greater than 49. t and u each represent an integer of at least 1 and no greater than 50. r+s+t+u=100. r+t=s+u. X and Y each represent, independently of one another, a divalent group represented by chemical formula (1-1), chemical formula (1-2), chemical formula (1-3), or chemical formula (1-4). X and Y are different from one another. 

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer contains at least a charge generating material, a charge transport material, and a binder resin. The binder resin includes a polyarylate resin. The polyarylate resin is represented by general formula (1) shown below. In general formula (1), X represents a divalent group represented by chemical formula (1-1), (1-2), (1-3), or (1-4) shown below. 

Electrophotographic photosensitive member

A triarylamine derivative represented by general formula (1) below. In the general formula (1), R, R, R, R, R, R, R, and Reach represent, independently from one another, a hydrogen atom, an optionally substitute alkyl group having a carbon number of at least 1 and no greater than 6, an optionally substituted alkoxy group having a carbon number of at least 1 and no greater than 6, or an optionally substituted aryl group having a carbon number of at least 6 and no greater than 14, Rrepresents an alkyl group having a carbon number of at least 1 and no greater than 4, X represents an alkylene group having a carbon number of at least 1 and no greater than 6 or an oxygen atom, and n represents an integer of 1 to 3. 

Triarylamine derivative, electrophotographic photosensitive member, and method for producing electrophotographic photosensitive member

A multi-layer electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer includes a charge generating layer and a charge transport layer. The charge generating layer contains a charge generating material. The charge transport layer contains a charge transport material, a binder resin, and silica particles. The charge transport layer is a monolayer. The charge transport layer is disposed as an outermost surface layer of the multi-layer electrophotographic photosensitive member. The silica particles have a content of at least 0.5 parts by mass and no greater than 15 parts by mass relative to 100 parts by mass of the binder resin. The binder resin includes a polyarylate resin. The polyarylate resin has a repeating unit represented by general formula (I) shown below. In general formula (I), R-Rand Y are defined as those described in the specification. 

Multi-layer electrophotographic photosensitive member

A multi-layer electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer includes a charge generating layer and a charge transport layer. The charge generating layer contains a charge generating material. The charge transport layer contains a hole transport material and a binder resin. The charge generating material contains a titanyl phthalocyanine that exhibits a main peak at a Bragg angle (2&#x3b8;&#xb1;0.2&#xb0;) of 27.2&#xb0; in a CuK&#x3b1; characteristic X-ray diffraction spectrum. The hole transport material contains a triarylamine derivative represented by generic formula (1). The hole transport material has a mass ratio of at least 0.30 and no greater than 0.55 relative to the binder resin in the charge transport layer. In general formula (1), R, R, l, and m are the same as those defined in the specification. 

Multi-layer electrophotographic photosensitive member, process cartridge, and image forming apparatus

A photosensitive layer in a multilayer electrophotographic photoconductor includes a charge-generation layer including a charge-generating material having, as a major component, a titanyl phthalocyanine crystal which satisfies the conditions (A) and (B) below and a base resin, and a charge-transport layer including a charge-transporting material, the charge-generating material having, as a major component, the titanyl phthalocyanine crystal which has absorption at a wavelength of a charge-neutralizing light and which satisfies the conditions (A) and (B) or an X-form metal-free phthalocyanine crystal which has absorption at the wavelength of the charge-neutralizing light, and a binder resin. (A) In a Cu&#x2014;K&#x3b1; characteristic X-ray diffraction spectrum, one peak is present at a Bragg angle 2&#x3b8;&#xb1;0.2&#xb0;=27.2&#xb0;. (B) In a differential scanning calorimetry, one peak is present in a range of 270&#xb0; C. to 400&#xb0; C. except for peaks attributed to vaporization of adsorption water.

Multilayer electrophotographic photoconductor and image-forming apparatus

An electrophotographic photosensitive member has a photosensitive layer. The photosensitive layer is a multi-layer photosensitive layer having a charge transport layer being an outermost layer or a single-layer photosensitive layer. The amount of silica particles contained in the photosensitive layer is at least 0.5 parts by mass and no greater than 15 parts by mass relative to 100 parts by mass of a binder resin contained in the photosensitive layer.

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer includes a charge generating layer and a charge transport layer located on the charge generating layer. The charge transport layer contains a pigment that is absorptive with respect to a wavelength of exposed light. The pigment is a metal phthalocyanine pigment represented by General Formula (I) or a metal-free phthalocyanine pigment represented by General Formula (II), where X represents a sulfur atom or an oxygen atom. Rrepresents an aryl group or an alkyl group. R-Reach represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, a phenoxy group, an alkylthio group, a phenylthio group, or a dialkylamino group. M represents a metal atom. Y represents non-substitution or an alkyl group, an alkoxy group, an aryloxy group, a halogen atom, an oxygen atom, or a hydroxyl group. 

An electrophotographic photosensitive member includes a photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, and a binder resin. The hole transport material contains an amine stilbene derivative represented by a general formula (1), and the binder resin contains a polycarbonate resin represented by a general formula (2). 

In some embodiments, a drum unit may include an electrophotographic photosensitive member having a base member and a photosensitive layer on the base member. An embodiment may include a cleaning blade configured to abut the photosensitive layer to remove a developer remaining on the photosensitive layer of the electrophotographic photosensitive member. Some embodiments may include side seals disposed at both ends of the cleaning blade to inhibit leakage of the developer. In some embodiments, a portion of a side seal may be in contact with at least a portion of the surface and an end face of the photosensitive layer.

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Osaka, Japan

Kensuke Okawa