Canon Kabushiki Kaisha

Hiroshi Morishita

Minoru Nakamura

Kenta Matsunaga

Kazutoshi Ishida

Toru Ishii

Yuji Sakurai

Ryo Sugiyama

Kentarou Nakamura

Mitsuru Okuda

Yoshinobu Ogawa

Sinya Tokitou

The developing member includes a substrate, and an electroconductive layer on the substrate, wherein the electroconductive layer has electrically insulating domains on an outer surface thereof, the domains being independent from each other, the developing member has an outer surface including a surface of the electroconductive layer and surfaces of the domains, and wherein, when each of the domains is orthographically projected onto the surface of the electroconductive layer, defining respective areas of projected images of the domains as S, and defining respective areas of convex envelopes of the projected images as H, at least one domain satisfies the relation represented by 0.05&#x2264;S/H&#x2264;0.80.

Developing member having outer surface with independent electrically insulating domains, electrophotographic process cartridge, and electrophotographic image forming apparatus

Provided is an electrophotographic member which can suppress adhesion of the toner component and fogging even in the case of printing a large number of sheets. The electrophotographic member includes an electroconductive support and an elastic layer and has convex portions composed of the elastic layer on a surface of the electrophotographic member and a filled portion containing a resin at a valley portion between the convex portions, the filled portion has a height lower than heights of the convex portions, and the surface of the electrophotographic member has a specific Martens hardness.

Electrophotographic member, process cartridge, and electrophotographic image forming apparatus

The present disclosure provides developing member superior in triboelectric charge imparting ability to a toner. The developing member includes a substrate and a surface layer, the surface layer containing alumina particles and a resin, the surface layer having protrusions on the surface thereof. Each of the protrusions containing the alumina particles, part or all of the alumina particles being exposed at the surfaces of the protrusions, and the resin being interposed among the alumina particles.

Developing member having alumina particles exposed within protrusions

A developer quantity control blade is provided which can sufficiently impart charge to toner and which allows bleeding of a material from a blade member to be suppressed even in application of a voltage. The developer quantity control blade includes a supporting member and a blade member, wherein the blade member is composed of a thermoplastic elastomer composition including a block copolymer having a polyamide structure and a polyether structure, and an ion conductive agent; in the blade member, a quantity of an extraction component to be extracted with methyl isobutyl ketone as a solvent is 0.5% by mass or more and 2.4% by mass or less; and a quantity of a molecule having a molecular weight of 5000 or less in the extraction component is 70% by mass or more.

Developer quantity control blade having blade member composed of a thermoplastic elastomer composition and image forming apparatus

Growing community of inventors

Tsukuba, Japan

Hiroshi Morishita