Sumitomo Riko Company Limited

Takeru Horiuchi

Shinkichi Kashihara

Yoshihiro Saito

Kengo Fujii

Naoki Akira

Shimpei Miyagawa

Yosuke Hayashi

Daisuke Inoue

Yuma Yoshida

Shuichi Egawa

Manabu Sakuda

Keiichi Ikegami

Kenta Nakazato

Takenori Saito

Akitoshi Morita

Provided is a charging roll for electrophotographic equipment with which any increase in resistance and any bleeding of ionic electroconductive agent while energization persists can be minimized. A charging rollfor electrophotographic equipment, the charging rollcomprising a shaft bodyand an elastic layerthat is formed on the outer peripheral surface of the shaft body, the elastic layerbeing a crosslinked article of a rubber composition containing the following components (a) to (e). (a) One or more selected from hydrin rubber and nitrile rubber, (b) a crosslinking agent, (c) an ionic electroconductive agent, (d) one or more selected from piperidinyloxy radical compounds and phenolic antioxidants, and (e) one or more selected from salts of cyclic amidine compounds and thiophthalimide compounds.

Charging roll for electrophotographic equipment

Provided is a conductive roll for an electrophotographic machine. The conductive roll is a charging roll and includes a shaft body, and an elastic body layer formed on an outer periphery of the shaft body. The elastic body layer is a crosslinked body of a composition containing a diene-based polymer (a), a sulfur or peroxide crosslinking agent (b), carbon black (c), and a coupling agent (d). (c) has a specific surface area of 40 to 300 m/g. (d) is a coupling agent having a NHRgroup and a SSOH group, or a coupling agent having a NHRgroup and an ene structure (where Ris H or a hydrocarbon group having 1 to 8 carbon atoms). The contents of (c) and (d) in the composition are respectively 10 to 45 parts by mass and 0.5 to 20 parts by mass with respect to 100 parts by mass of (a).

Conductive roll for electrophotographic machine

A development roller for an electrophotographic device that can both reduce resistance and suppress bleeding-out of an ion-conducting agent is provided. A development roller for an electrophotographic deviceis provided with a shaft body, an elastic body layerformed on the outer periphery of the shaft body, and a surface layer formed on the outer periphery of the elastic body layer. The surface layerincludes the following constituents (a) to (c), and the content of constituent (b) is 3.0 to 60 parts by mass, relative to 100 parts by mass of constituent (a). Constituent (a) is a binder comprising acrylonitrile-butadiene rubber, where the content of acrylonitrile is 31 mass % or more and 36 mass % or less. Constituent (b) is an ion-conducting agent. Constituent (c) is an acrylic polymer comprising at least one selected from among a silicone group and a fluorine group.

Development roller for electrophotographic device

An elastic body layer is composed of a conductive rubber composition containing an isoprene rubber, a rubber other than the isoprene rubber, and carbon black. The elastic body layer is phase-separated into a first rubber phase containing the isoprene rubber and a second rubber phase containing the rubber other than the isoprene rubber; in the range of a 5 &#x3bc;m&#xd7;5 &#x3bc;m square of an arbitrary cross section of the elastic body layer, the area ratio of the first rubber phase is within a range of 10 to 90%. The resistance value of the elastic body layer is within a range of 1.0&#xd7;10to 1.0&#xd7;10&#x3a9;. A surface layer contains an electronic conductive agent and a crosslinked body of at least one polyurethane resin of an ether polyurethane resin and a carbonate polyurethane resin, and the glass transition point of the surface layer is within a range of &#x2212;10 to &#x2212;70&#xb0; C.

Charging roll or developing roll for electrophotographic device

An electrophotography device development roller in which an increase in the electric charge of a toner is suppressed is provided. This electrophotography device development rolleris provided with a shaft, an elastic layerformed on the outer circumference of the shaft, and a surface layerformed on the outer circumference of the elastic layer. The surface layercontains components (a) to (c) below. Component (a) a binder comprising acrylonitrile-butadiene rubber having an acrylonitrile amount of 30 mass % or more; component (b) an ion-conducting agent comprising at least one selected from a phosphonium salt and a pyridinium salt; and component (c) an electric charge regulator comprising an acrylic polymer having a silicone group or fluorine-containing group and a cationic group.

Electrophotography device development roll including shaft, elastic layer and surface layer

The present disclosure provides a charging member for electrophotographic equipment capable of providing constant and excellent uniform chargeability over a long period of time from low-temperature and low-humidity through high-temperature and high-humidity environments, while suppressing bleeding. A charging member for electrophotographic equipment includes an elastic layer and a surface layer formed around the elastic layer. The elastic layer includes the following (a) through (c): (a) an ion conducting agent that is solid at room temperature; (b) an ion conducting agent that is liquid at room temperature; and (c) an electron conducting agent with an average grain diameter of 25 to 90 nm and a DBP absorption of 152 ml/100 g or below.

Charging member for electrophotographic equipment

A charging member for an electrophotographic apparatus in which image defects caused by bleeding of an ion-conductive agent are suppressed and excellent chargeability can be maintained. In a charging member for an electrophotographic apparatus including a base layer composed of a conductive rubber elastomer and a surface layer, the base layer is a cross-linked body of a conductive rubber composition containing (a) a cross-linkable rubber, (b) a cross-linking agent, (c) an ion-conductive agent represented by a general formula (1) below, and (d) carbon black. Here, Rand Rare allyl groups, Ris a methyl group or an ethyl group, and Ris a linear alkyl group having a carbon number of 6-8. Xis a sulfonate anion having a fluorine atom or a bis(sulfonyl) imide anion having a fluorine atom.

Charging member for electrophotographic apparatus

To provide a conductive roll for an electrophotographic apparatus that includes a conductive rubber elastic body layer having a lower hardness and lower settling properties than a conventional conductive rubber elastic body layer. A conductive rollfor an electrophotographic apparatus includes a shaft bodyand a conductive rubber elastic body layerprovided on the outer periphery of the shaft bodythe conductive rubber elastic body layercontaining polar rubber, non-polar rubber, and a dispersing agent, wherein the polar rubber is at least one of nitrile rubber, hydrin rubber, and chloroprene rubber, wherein the non-polar rubber is at least one of isoprene rubber, hydrogenated isoprene rubber, and natural rubber, and wherein the dispersing agent is at least one of a polymer containing a block made of a nitrile rubber component and a block made of an isoprene rubber component, modified natural rubber, and modified isoprene rubber.

Growing community of inventors

Aichi, Japan

Takeru Horiuchi