Canon Kabushiki Kaisha

Masataka Kawahara

Takeshi Murakami

Kaname Watariguchi

Tsutomu Nishida

Jumpei Kuno

Akira Yoshida

Harunobu Ogaki

Atsushi Ochi

Hiroki Uematsu

Junpei Kuno

Akira Shimada

Michiyo Sekiya

Akio Maruyama

Toshihiro Kikuchi

Takayuki Sumida

Akio Koganei

Kyoichi Teramoto

Atsushi Fujii

Tomohito Ishida

Kohei Makisumi

Shoma Hinata

Hirotoshi Uesugi

Masato Tanaka

Takashi Anezaki

Masaki Nonaka

Itaru Takaya

Hirofumi Kumoi

Yuka Ishizuka

Takeshi Ikeda

Kazuo Yoshinaga

Daisuke Miura

Hiroyuki Tomono

Kazumichi Sugiyama

Akihiro Maruyama

Yota Ito

Tatsuya Yamaai

Isao Kawata

Keiko Hiraoka

Yuto Ito

Kazuko Araki

Tetsuro Fukui

Hideki Kobayashi

Takanori Matsuda

Yuka Ishiduka

Kazunori Noguchi

Nobuo Kushibiki

Yuko Sato

Katsumi Aoki

Toru Masatomi

Kazushige Nakamura

Hidetoshi Hirano

Nobuyuki Ito

Kikuko Takeuchi

Shunichiro Nishida

Kazuko Sakuma

The electrophotographic photosensitive member has: a cylindrical support; a charge generating layer formed on the cylindrical support; and a charge transport layer formed on the charge generating layer, the charge generating layer contains a hydroxygallium phthalocyanine crystal having a particular CuK&#x3b1; characteristic X-ray diffraction peak, a titanyl phthalocyanine crystal having a particular CuK&#x3b1; characteristic X-ray diffraction peak or a chlorogallium phthalocyanine crystal having a particular spectral absorption spectrum as a charge generating material, and in the charge generating layer, with respect to the film thickness of the charge generating layer, when a region from the central position of an image forming area to the end position of the image forming area is divided in the axial direction of the cylindrical support into five equal regions and the average film thickness of the charge generating layer in each region satisfies a specific condition.

Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

Provided is an electrophotographic photosensitive member which enables a reduction in unevenness in distribution of the post-exposure potential of the photosensitive member and a reduction in unevenness in life of the photosensitive member in the axial direction. An electrophotographic photosensitive member, including a cylindrical support, a charge generating layer, and a charge transport layer in this order, wherein when a region from a central position of an image formation region of the electrophotographic photosensitive member to an end position of the image formation region in the axial direction of the cylindrical support is equally divided into five regions, average film thicknesses of the charge generating layer in the five regions satisfy specific relations in a film thickness of the charge generating layer and average film thicknesses of the charge transport layer in the five regions satisfy specific relations in a film thickness of the charge transport layer.

An electrophotographic photosensitive member, including a cylindrical support, a charge generating layer formed on the cylindrical support, and a charge transport layer formed on the charge generating layer, in which in the charge generating layer, when a region from a central position of an image forming region to an end position of the image forming region in an axis direction of the cylindrical support is divided equally into five regions, film thicknesses of the charge generating layers in each of the regions satisfy a specific relationship with each other, and in the charge transport layer, when a region from the central position of the image forming region to the end position of the image forming region in the axis direction of the cylindrical support is divided equally into five regions, film thicknesses of the charge transport layers in each of the regions satisfy a specific relationship with each other.

Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

Provided is an electrophotographic photosensitive member in which discharge streaks generated in an end portion can be suppressed. The electrophotographic photosensitive member includes a cylindrical support, a charge-generating layer, and a charge-transporting layer in the stated order. In the electrophotographic photosensitive member, when a region between a center position and a 90% position situated at a 90% of a length of from the center position to one end of the electrophotographic photosensitive member in an axial direction thereof from the center position, is defined as a region X, and a region between the 90% position and the end of the electrophotographic photosensitive member is defined as a region Z. Average thicknesses in regions obtained by equally dividing the region X into five and regions obtained by equally dividing the region Z into three satisfy particular relationships.

An electrophotographic photosensitive member includes, in this order, a support, a charge generating layer having a thickness of more than 200 nm and containing a hydroxygallium phthalocyanine pigment or a chlorogallium phthalocyanine pigment as a charge generating material, and a charge transport layer containing a charge transporting material. The charge generating material satisfies a requirement for a specific parameter.

An electrophotographic photoconductor comprises a support, an undercoat layer, a charge generation layer, and a hole transport layer in this order. The undercoat layer comprises an electron transport substance, and the charge generation layer comprises a gallium phthalocyanine crystal and an amide compound represented by formula (N1): where Rrepresents a methyl group, a propyl group, or a vinyl group.

Electrophotographic photoconductor, process cartridge, and electrophotographic apparatus

An electrophotographic photosensitive member includes a support member, a charge generating layer containing a phthalocyanine pigment as a charge generating material, a charge transport layer containing a charge transporting material in this order. The charge generating layer has a thickness of less than 200 nm, and the phthalocyanine pigment includes phthalocyanine crystalline particles having a particle size distribution and satisfies a requirement that the volume average of the products of &#x3a6;i and &#x3a8;i is 0.31 or more.

An electrophotographic photosensitive member includes a support and a photosensitive layer in this order. The photosensitive layer contains a chlorogallium phthalocyanine crystal obtained by mixing a hydroxygallium phthalocyanine crystal and an aqueous hydrochloric acid solution.

Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus, and chlorogallium phthalocyanine crystal and method for producing the same

An electrophotographic photosensitive member includes a substrate and a photosensitive layer containing a phthalocyanine pigment. The crystalline particles of the phthalocyanine pigment have a crystallite correlation length r and a particle size R of 400 nm or less, and a parameter k defined by r/R is in the range of 0.17 to 0.42.

Electrophotographic photosensitive member, process cartridge, electrophotographic apparatus, and phthalocyanine pigment

The present invention provides: an electrophotographic photosensitive member which reduces image defects due to ghosting not only under a normal temperature and normal humidity environment but also even under a low temperature and low humidity environment; and a novel phthalocyanine crystal. The electrophotographic photosensitive member of the present invention comprises a photosensitive layer which comprises a phthalocyanine crystal in which a N,N-dimethylformamide is contained. The content of the N,N-dimethylformamide is 0.1% by mass or more and 1.5% by mass or less based on the phthalocyanine crystal.

Manufacturing method of phthalocyanine crystal by milling crystal transformation for at least 1,000 hours

An electrophotographic photosensitive member has a support, a charge generation layer, and a charge transport layer in this order, the charge transport layer containing a charge transport material. The charge transport layer is a surface layer of the electrophotographic photosensitive member and contains a polycarbonate resin having a structural unit selected from group A and a structural unit selected from group B.  

Electrophotographic photosensitive member, method for manufacturing electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

An electrophotographic photosensitive member has a support, a charge generation layer, and a charge transport layer in this order, the charge transport layer containing a charge transport material. The charge transport layer is a surface layer of the electrophotographic photosensitive member and contains a polycarbonate resin having a structural unit selected from group A and a structural unit selected from group B (groups A and B defined in the disclosure).

An electrophotographic photosensitive member includes a support and a photosensitive layer in this order. The photosensitive layer contains a chlorogallium phthalocyanine crystal represented by formula (1) in which at least one organic compound selected from N,N-dimethylformamide and dimethyl sulfoxide is contained. The content of the organic compound contained in the chlorogallium phthalocyanine crystal represented by the formula (1) is 0.10 mass % or more and 0.80 mass % or less based on a content of the chlorogallium phthalocyanine crystal represented by the formula (1).

An electrophotographic photosensitive member includes a support and a photosensitive layer in this order. The photosensitive layer contains a chlorogallium phthalocyanine crystal. The chlorogallium phthalocyanine crystal has one or more peaks in each of a wavelength range of 646 nm or more and 668 nm or less and a wavelength range of 782 nm or more and 809 nm or less in an absorption spectrum. When a peak with a maximum absorbance among the peaks in the wavelength range of 646 nm or more and 668 nm or less is assumed to be a first peak and a peak with a maximum absorbance among the peaks in the wavelength range of 782 nm or more and 809 nm or less is assumed to be a second peak, an absorbance of the first peak is larger than an absorbance of the second peak.

An electrophotographic photosensitive member can provide images in which black spots and fogging are suppressed and density unevenness due to coating unevenness of the charge generation layer is suppressed. The charge generation layer of the electrophotographic photosensitive member contains a gallium phthalocyanine crystal, a nitrogen-containing heterocyclic compound, and an amide compound represented by a formula (1), and a nitrogen atom in a heterocyclic ring of the nitrogen-containing heterocyclic compound has a substituent. 

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Mishima, Japan

Masataka Kawahara