Electrical conductive roller
An electrical conductive roller 1 that includes a shaft member 2 born at both end portions in a lengthwise direction thereof, and one or more elastic layers 3 arranged on a radially outside thereof, where each elastic layer has a glass transition point of not higher than −40° C., and at least one of the elastic layers is constituted with a ultraviolet curing type resin containing an electrically conducting agent and a ultraviolet initiator.
1. An electrical conductive roller comprising a shaft member born at both end portions in a lengthwise direction thereof, and one or more elastic layers arranged on a radially outside thereof and having a glass transition point of not higher than −40° C., wherein at least one of the elastic layers is constituted with an ultraviolet curing type resin containing an electrically conducting agent and an ultraviolet initiator, wherein one or more surface layers having a glass transition point of higher than −40° C. are arranged outside of an outermost elastic layer and such a surface layer is constituted with an ultraviolet curing resin containing an electrically conducting agent and an ultraviolet initiator.
2. An electrical conductive roller according to claim 1 , wherein the roller is used as a developing roller for feeding a non-magnetic developing agent supported on an outer peripheral face thereof to a latent image support, and an outermost layer of the elastic layers is constituted with a resin dispersed with fine particles.
3. An electrical conductive roller according to claim 2 , wherein the fine particles have an average particle size of 1-50 μm.
4. An electrical conductive roller according to claim 2 , wherein a content of the fine particles in the outermost elastic layer is 0.1-100 parts by weight based on 100 parts by weight of the resin.
5. An electrical conductive roller according to claim 1 , wherein the electrically conducting agent is a carbon-based conducting agent, an ion conducting agent or a metal oxide, and when the carbon-based conducting agent is included as the electrically conducting agent, a substance having a maximum wavelength of an ultraviolet absorption wavelength zone of not less than 400 nm is included in the ultraviolet initiator.
6. An electrical conductive roller according to claim 1 , wherein a crosslinking density of the ultraviolet curing resin or electron beam curing resin in the elastic layer is made smaller than that of the surface layer.
7. An electrical conductive roller according to claim 1 , wherein the shaft member is constituted with a metal pipe or a hollow cylindrical body or a solid cylinder made from a resin containing an electrically conducting agent.