| 摘要 |
PURPOSE:To effectively prevent extinction of permanent charges in an electret layer, to stably carry a charged toner for a long time on an electret sleeve, and to significantly improve durability of a developing device used for an electrophotographic device such as copying machine. CONSTITUTION:This electret sleeve to carry a developer consists of a conductive base body and an electret layer having permanent charges formed on the base body. A protective layer having 5mum thickness of a fluorine-contg. polymer comprising the repeating unit expressed by formula is formed on the electret layer. In the formula, x, y and z are 0 or 1. |
