| 摘要 |
PROBLEM TO BE SOLVED: To provide a dry toner which ensures rapid rising of a charge amount, causes no lowering of image density even in a high temperature and high humidity environment, has superior environmental stability, and an improved sleeve ghost. SOLUTION: The toner contains at least a binder resin and magnetic iron oxide, wherein the magnetic iron oxide contains at least 0.1-2.0 mass% Si, 0.1-1.5 mass% Zn and 0.1-1.5 mass% Ti each based on the amount of the magnetic iron oxide, and it is characterised in that the rate of Si dissolution at the time of dissolving 5% of the magnetic iron oxide from the surface is 5-60%, the rate of Zn dissolution at the time of dissolving 5% of the magnetic iron oxide from the surface is 30-95%, the rate of Ti dissolution at the time of dissolving 5% of the magnetic iron oxide from the surface is 50-100%, and the weight average diameter of the toner containing the magnetic iron oxide is 4.0-12.0μm. COPYRIGHT: (C)2005,JPO&NCIPI |
