| 摘要 |
<p>PURPOSE:To reduce the size, weight and cost of a developing device by supplying electret toners to a developing region by a toner transporting member consisting of a dielectric substance layer which is permanently electrostatically charged to the polarity reverse from the polarity of the toners and a protective dielectric substance layer. CONSTITUTION:The developer transporting member (developing sleeve) 1 is composed by coating the surface of a sleeve base body 2 with the electret dielectric substance layer 3 which is permanently electrostatically charged to the polarity reverse from the electrostatic charge polarity of the toners and the surface protective layer. This developing sleeve 1 exists in the aperture of the developing device 8 and the electret toners 11 replenished via a supplying mechanism 12 are electrostatically attracted to the sleeve, by which a toner layer 13 is formed on the surface thereof. The electret toners 11 are obtd. by electretting the toner particles consisting of a fixing resin consisting of a styrene resin, etc., and coloring agents. The material for forming the electret dielectric substance layer 3 is exemplified by film forming materials, such as tetrafluoroethylene resins, enabling permanent electric polarization, etc. As a result, the need for triboelectrostatic charge mechanisms in a developing device 8 is eliminated at all.</p> |
