| 摘要 |
PURPOSE:To stabilize the triboelectrostatic chargeability of the developer and to form the developer so as to exhibit uniform positive chargeability even under various environments by incorporating a carbon black treated by a specific silicone oil into the developer. CONSTITUTION:The developer is so formed as to contain the carbon black treated with the silicone oil having amine in the side chain contg. the constituting unit expressed by formula I. In the formula, R1 denotes hydrogen, alkyl group, etc.; R2 denotes an alkylene group or phenylene group; R3, R4 denote hydrogen, aryl group, etc. The amt. of the silicone oil to be added to the carbon black is specified to 5 to 50pts.wt. per 100pts.wt. carbon black. The developer having the positive chargeability without having a change in electrostatic characteristics even after the execution of repetitive copying over a long period of time under low humidity is obtd. in this way. |
