Abstract: A developing roller includes an ultraviolet-curing type resin layer and using a carbon-based electrically conducting agent for giving an electrical conductivity to the resin layer, as well as an imaging apparatus using the same. The developing roller 1 includes a shaft member 2 including a hollow cylindrical body or a solid cylindrical body of a resin containing an electrically conducting agent and a resin layer 4. The resin layer 4 is made of a resin having fine particles dispersed therein, wherein a ratio a/b of average particle size of fine particles a to a total thickness of resin layers b is greater than 2.0 and less than or equal to 5.0.

Abstract: There are provided a developing roller capable of making useless a drying line in the formation of a resin layer and using a carbon-based electrically conducting agent for giving an electrical conductivity to the resin layer as well as an imaging apparatus using the same. The developing roller 1 comprises a shaft member 2 constituted with a hollow cylindrical body or a solid cylindrical body of a resin containing an electrically conducting agent and a resin layer 4. The resin layer 4 is made from a ultraviolet-curing type resin containing a carbon-based electrically conducting agent and a ultraviolet initiator, in which the ultraviolet initiator has a maximum wavelength in a ultraviolet absorption wavelength region of not less than 400 nm. The resin layer 4 may be made from an electron beam curing type resin containing the electrically conducting agent.

Abstract: A lock nut of the present invention comprises a metal nut base body and a synthetic resin portion, an internally threaded portion having a diameter smaller than that of an internally threaded portion of the nut base body and extending therefrom being formed in a cap-like portion formed at one end of the nut base body. This lock nut can prevent the occurrence of looseness after the lock nut has been fastened.