Provided is a developing roller including a shaft body, an elastic layer formed on an external circumference of the shaft body, and a surface layer formed on an external circumference of the elastic layer. The surface layer is formed of polyurethane containing a reaction product of a fluoroethylene vinyl ether copolymer and an isocyanurate form of isocyanate and having a film thickness of from 0.5 μm through 2.0 μm. The developing roller has grooves in a surface of the developing roller. The angle of the grooves from a circumferential direction is from 0 degrees through 30 degrees.

Provided are a continuous-fiber nonwoven fabric having excellent denseness, a composite material including the nonwoven fabric and having good appearance, and a method for producing the composite material. The continuous-fiber nonwoven fabric includes fibers containing an amorphous thermoplastic phenoxy resin as a main component, wherein the thermoplastic phenoxy resin has a weight-average molecular weight in a range of from 10,000 to 100,000 and a glass transition temperature equal to or lower than 100° C. For example, the continuous-fiber nonwoven fabric may be a melt-blown nonwoven fabric or a spunbonded nonwoven fabric.

A polyether compound having a cationic group and two or more chain end groups and, wherein all of the chain end groups are any of a hydroxyl group and an azide group is provided.

An electrochromic device includes a cathodic compartment including a cathodic material; an anodic compartment including an anodic material; and a transparent, ion-selective membrane displaced between the cathodic compartment and the anodic compartment wherein the transparent, ion-selective membrane is a cationic polymer.

An inventive charging roller (1) includes a roller body (2) which is formed of a crosslinked product of a rubber composition containing a rubber component including 30 to 70 parts by mass of GECO, 15 to 60 parts by mass of IR and not less than 1 part by mass of SBR and/or NBR based on 100 parts by mass of the overall rubber component and has an outer peripheral surface (5) finished in a finish-polished surface. An inventive production method includes the steps of: forming a roller body (2) from the crosslinked product of the rubber composition described above; and wet-polishing or mirror-polishing an outer peripheral surface (5) of the roller body (2) into a finish-polished surface.

A rubber composition capable of forming a foam such as a roller main body which has a low rubber hardness and is soft in a state in which an average cell diameter thereof is small is provided. The rubber composition includes NBR whose Mooney viscosity is 15 to 50 having a proportion being 10 parts by mass or more in 100 parts by mass of the total amount of rubber, epichlorohydrin rubber whose Mooney viscosity is 5 to 35 having a proportion being 10 parts by mass or more in 100 parts by mass of the total amount of rubber, and 10 parts by mass or less of carbon black and 7 parts by mass or less of a foaming agent with respect to 100 parts by mass of the total amount of rubber, and has a Mooney viscosity of 35 or less.

An inventive electrically conductive rubber composition contains: a rubber component including SBR and/or NBR, and 20 to 30 parts by mass of epichlorohydrin rubber based on 100 parts by mass of the overall rubber component; a crosslinking component; a foaming component; and a potassium salt of an anion having a fluoro group and a sulfonyl group in its molecule, the potassium salt being present in a proportion of not less than 0.01 part by mass and not greater than 1 part by mass based on 100 parts by mass of the overall rubber component. An inventive transfer roller (1) includes a roller body (2) formed from the electrically conductive rubber composition.

A rubber composition capable of forming a foam such as a roller main body which has a low rubber hardness and is soft in a state in which an average cell diameter thereof is small is provided. The rubber composition includes NBR whose Mooney viscosity is 15 to 50 having a proportion being 10 parts by mass or more in 100 parts by mass of the total amount of rubber, epichlorohydrin rubber whose Mooney viscosity is 5 to 35 having a proportion being 10 parts by mass or more in 100 parts by mass of the total amount of rubber, and 10 parts by mass or less of carbon black and 7 parts by mass or less of a foaming agent with respect to 100 parts by mass of the total amount of rubber, and has a Mooney viscosity of 35 or less.

A rubber composition is provided. The rubber roller including a roller body formed of a porous body formed by foaming and crosslinking the rubber composition and an image forming device including the rubber roller are also provided. In the rubber composition, fine porous particles of at least one type selected from a group consisting of zeolite, activated carbon, and diatomite along with a crosslinking component and a foaming component are mixed into a rubber that contains at least one type selected from a group consisting of diene-based rubbers and ethylene propylene-based rubbers and an ion-conductive rubber. A rubber roller includes a roller body that is formed by cylindrically extrusion-molding and crosslinking the rubber composition. An image forming device has the rubber roller 1 assembled thereinto.

An electrochromic device includes a cathodic compartment including a cathodic material; an anodic compartment including an anodic material; and a transparent, ion-selective membrane displaced between the cathodic compartment and the anodic compartment wherein the transparent, ion-selective membrane is a cationic polymer.