| 摘要 |
PROBLEM TO BE SOLVED: To provide toner which retains low temperature fixability, stability of a charged state, storage stability and environmental stability even when the particle diameter of the toner is made small. SOLUTION: The toner uses a hybrid of a polyester unit and a vinyl polymer unit as a binder resin and has an acid value of 5-40 mgKOH/g, an average circularity of≥0.94 and a difference M1-M2 of≤0.06 mass% between the amount M1 of adsorbed moisture at an arbitrary relative humidity in an adsorption process and the amount M2 of adsorbed moisture in a desorption process at the same humidity on an adsorption/desorption isothermal line at 30°C. The toner may be a negative charge type toner containing a sulfonic acid group-containing polymer as an auxiliary charge controlling agent, the toner contains Fischer-Tropsch wax as an inner additive and the DSC curve of the wax has the maximum peak at 70-140°C. A magnetic material used as a colorant is octahedral magnetic iron oxide and hydrophobed silica or titania is used as an external additive. COPYRIGHT: (C)2004,JPO |
