A method of production of a polyether rubber containing unit expressed by the following general formula (1) in 0.1 mol % or more and less than 30 mol % obtained by reacting a polyether rubber containing epihalohydrin monomer unit in 0.1 mol % or more and a nitrogen atom-containing aromatic heterocyclic compound by kneading in the presence of an acid acceptor containing at least a hydrotalcite having a nitrogen adsorption specific surface area as measured by a BET method of 10 m.sup.2/g or more is provided. ##STR00001## wherein, in the above general formula (1), A.sup.+ is a group containing a cationic nitrogen-containing aromatic heterocyclic ring, and is bonded with a carbon atom at the 2 position shown in the above general formula (1) through a nitrogen atom constituting the cationic nitrogen-containing aromatic heterocyclic ring, and X.sup. is any counter anion.

A method of production of a polyether rubber containing unit expressed by the following general formula (1) in 0.1 mol % or more and less than 30 mol % obtained by reacting a polyether rubber containing epihalohydrin monomer unit in 0.1 mol % or more and a nitrogen atom-containing aromatic heterocyclic compound by kneading in the presence of an acid acceptor containing at least a hydrotalcite having a nitrogen adsorption specific surface area as measured by a BET method of 10 m.sup.2/g or more is provided. ##STR00001## wherein, in the above general formula (1), A.sup.+ is a group containing a cationic nitrogen-containing aromatic heterocyclic ring, and is bonded with a carbon atom at the 2 position shown in the above general formula (1) through a nitrogen atom constituting the cationic nitrogen-containing aromatic heterocyclic ring, and X.sup. is any counter anion.

An epichlorohydrin rubber composition that includes 100 parts by weight of an epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer rubber, 0 to 60 parts by weight of carbon black, and 30 to 60 parts by weight of a flat tiller. The crosslinked epichlorohydrin rubber is prepared by crosslinking the composition with a crosslinking agent. Materials for accumulators contain the crosslinked rubber.

An epichlorohydrin rubber composition that includes 100 parts by weight of an epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer rubber, 0 to 60 parts by weight of carbon black, and 30 to 60 parts by weight of a flat tiller. The crosslinked epichlorohydrin rubber is prepared by crosslinking the composition with a crosslinking agent. Materials for accumulators contain the crosslinked rubber.

An epichlorohydrin rubber composition that includes 100 parts by weight of an epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer rubber, 0 to 60 parts by weight of carbon black, and 30 to 60 parts by weight of a flat tiller. The crosslinked epichlorohydrin rubber is prepared by crosslinking the composition with a crosslinking agent. Materials for accumulators contain the crosslinked rubber.

To provide a method for producing a rubber composition which gives a cross-linked rubber which has a low volume resistivity value, which is low in hardness, and which is kept down in contamination of the photoconductor when used as a conductive member. A production method of a rubber composition comprising a step of mixing a polyether rubber which is dissolved in a solvent at 0.1 to 30 wt % of concentration and a liquid ethylenically unsaturated nitrile-conjugated diene copolymer rubber in a solution is provided.

To provide a method for producing a rubber composition which gives a cross-linked rubber which has a low volume resistivity value, which is low in hardness, and which is kept down in contamination of the photoconductor when used as a conductive member. A production method of a rubber composition comprising a step of mixing a polyether rubber which is dissolved in a solvent at 0.1 to 30 wt % of concentration and a liquid ethylenically unsaturated nitrile-conjugated diene copolymer rubber in a solution is provided.

To provide a method for producing a rubber composition which gives a cross-linked rubber which has a low volume resistivity value, which is low in hardness, and which is kept down in contamination of the photoconductor when used as a conductive member. A production method of a rubber composition comprising a step of mixing a polyether rubber which is dissolved in a solvent at 0.1 to 30 wt % of concentration and a liquid ethylenically unsaturated nitrile-conjugated diene copolymer rubber in a solution is provided.

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 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.