Canon Kabushiki Kaisha

Yoshio Kashizaki

Hajime Miyazaki

Koichi Suzuki

Shintetsu Go

Masato Tanaka

Akihiro Senoo

Kazuma Sato

Toshie Miyaji

Kazuo Yoshinaga

Akira Shimada

Kunihiko Sekido

Yuichi Hashimoto

Jian Chen

Satomi Sugiyama

Satomi Ohmura

Teigo Sakakibara

Toshihiro Kikuchi

Yukio Nagase

Mamoru Tanaka

Shoji Umehara

Yasuko Hayashi

A polymer has a structural unit represented by the following formula (1):

Polymer, electrophotographic photosensitive member containing the polymer, process cartridge and electrophotographic apparatus having the electrophotographic photosensitive member

An electrophotographic photosensitive member is constituted by disposing a photosensitive layer including a charge generation layer and a charge transport layer on an electroconductive support. The charge transport layer has a thickness of at most 12 .mu.m and is formed by dispersing therein particles having a particle size of 1-3 .mu.m at a density of 1.times.10.sup.4 -2.times.10.sup.5 particles/mm.sup.2. The charge transport layer and the particles described above provides a difference in refractive index of at least 0.10. The photosensitive member is effective in providing good images free from black spots and interference fringes and with a good gradation-reproducing characteristic when used as a structural member of a process cartridge and an image forming apparatus.

Electrophotographic photosensitve member and image forming apparatus

An electrophotographic system is constituted by an electrophotographic photosensitive member, a charger for charging the photosensitive member to a potential, and an illuminator for illuminating the charged photosensitive member with a light beam to form an electrostatic image thereon. The electrophotographic photosensitive member has a potential-exposure energy characteristic providing an induction energy and a gamma valve varying depending on an electric field intensity induced by the charged potential. The electrophotographic system further includes a controller for controlling the charged potential on the photosensitive member corresponding to resolution and gradation data of an original, so as to optimally reproduce the resolution and gradation, as desired, of the original.

Electrophotographic apparatus and image forming method using a

An electrophotographic photosensitive member and a process cartridge and an electrophotographic apparatus. The process cartridge and the electrophotographic apparatus both contain the electrophotographic photosensitive member. The electrophotographic photosensitive member constitutes a conductive substrate and a photosensitive layer on the substrate. The photosensitive layer contains an azo pigment of formula (1), formula (2), formula (3), formula (4) or formula (5), as shown below: ##STR1##

Electrophotographic photosensitive member, process cartridge and

An electrophotographic photosensitive member is constituted by an electroconductive support, an intermediate layer disposed on the electroconductive support and a photosensitive layer disposed on the intermediate layer. The intermediate layer contains a copolymer having at least two species of a recurring unit having an amide acid structure and/or amide acid ester structure, thus resulting in good film-forming properties. The resultant photosensitive member is effective for providing a process cartridge and an electrophotographic apparatus respectively including the photosensitive member with a stable electric potential under any environmental condition to provide excellent images free from image defects for a long period.

Electrophotographic photosensitive member, process cartridge including

An electrophotographic photosensitive member, having a support, and an intermediate layer and a photosensitive layer disposed on the support in this order; the intermediate layer having a coated powder comprising a coating layer and barium sulfate fine particles coated with the coating layer; and the coating layer comprising tin oxide. The above intermediate layer is usable for constituting an electrophotographic apparatus providing stable potential properties and good image quality under overall environmental conditions including low-temperature and low-humidity condition to high-temperature and high-humidity condition.

Electrophotographic photosensitive member and electrophotographic

An electrophotographic photosensitive member is disclosed which has an electroconductive support, an interlayer, and a photosensitive layer. The interlayer contains a resin having a polyamic acid structure or a polyamic acid ester structure. A process cartridge and electrographic apparatus using the photosensitive member are also disclosed.

Electrophotographic photosensitive member, and process cartridge and

An electrophotographic photosensitive member includes, in orders, a supporting member, and an intermediate layer and a photoconductive layer. The intermediate layer contains a powder of fine particles of tin oxide containing phosphorus.

Electrophotographic photosensitive member having intermediate layer

An electrophotographic photosensitive member is constituted by an electroconductive support, an intermediate layer disposed on the electroconductive support and a photosensitive layer disposed on the intermediate layer. The intermediate layer contains a resin having a specific recurring unit containing polyamide acid structure and/or polyamide acid ester structure. The photosensitive member is effective for providing a process cartridge and an electrophotographic apparatus respectively including the photosensitive member with an excellent photosensitivity and a stable electric potential under any environmental condition.

An electrophotographic photosensitive member includes an electroconductive support and a photosensitive layer formed thereon, the photosensitive layer containing a resin having the acetal moiety represented by the formula [I] below: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, and R.sub.5 are independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, respectively, provided that all of R.sub.1, R.sub.2, R.sub.3, R.sub.4, and R.sub.5 are not simultaneously hydrogen atoms.

Electrophotographic photosensitive member, and electrophotographic

An electrophotographic photosensitive member is disclosed which has a photosensitive layer on a conductive support. The photosensitive layer contains an azo pigment of Formula (1):

An electrophotographic photosensitive member, comprising: an electroconductive support and a photosensitive layer disposed on the electroconductive support, wherein the photosensitive layer comprises a triazene compound represented by the following formula (1): ##STR1## wherein R denotes hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group.

Electrophotographic photosensitive member, electrophotographic

An electrophotographic photosensitive member has an electroconductive substrate and a photosensitive layer formed thereon. The photosensitive layer contains an acetal resin having a component unit represented by the following formula (1): ##STR1## wherein X is ##STR2## R.sub.1 is a substituted or unsubstituted aryl group and a substituted or unsubstituted heterocyclic group; R.sub.2 is a hydrogen atom and a substituted or unsubstituted alkyl group; R.sub.3 is a substituted or unsubstituted alkyl group; A is a substituted or unsubstituted heterocyclic group and ##STR3## R.sub.4 is a substituted or unsubstituted heterocyclic group; R.sub.5 is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group and a substituted or unsubstituted heterocyclic group; and n and m are each 0, 1, 2 and 3.

There is disclosed an electrophotographic photosensitive member having a photosensitive layer containing a disazo pigment represented by the following general formula (1) or (2); ##STR1## The photosensitive member has excellent durability and high sensitivity.

An electrophotographic photosensitive member has a photosensitive layer provided on an electroconductive support. The photosensitive layer contains an azo pigment represented by the general formula (I): ##STR1## wherein Ar.sub.1 and Ar.sub.2 are respectively a divalent aromatic hydrocarbon group or a divalent heterocyclic group which may be the same or different and may have a substituent, and A.sub.1 and A.sub.2 are respectively a coupler residue having a phenolic hydroxyl group which may be the same or different.

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Yokohama, Japan

Yoshio Kashizaki