| 摘要 |
PURPOSE:To enhance stability against the environment and pressure fixability, etc. by mixing an SnO2 type fine powder treated with a silane coupling agent on the outside of a toner consisting of a binder and a magnetic powder. CONSTITUTION:An SnO2 type fine powder treated with a silane coupling agent to give hydrophobic property exhibits an effect of not causing unevenness of image density even if a content of magnetic powder is small, and permits a magnetic developer to act effectively even under the environmental conditions of both high and low humidity. A preferable content of magnetic powder is 40- 60pts.wt. per 100pts.wt. of the binder, and a preferable mixing ratio of the SnO2 fine powder to the toner is (0.3-5):100 by weight. A preferably amt. of reactive silane to be added is 0.1-2wt% of SnO2, and its treatment method is like that of treating an ordinary inorg. fine powder with said agent. |
