| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic toner capable of maintaining image density and toner durability even in a use after long-term storage in a high-temperature and high-humidity environment. SOLUTION: The magnetic toner comprises: magnetic toner particles that at least contain a binder resin, a magnetic iron oxide and a releasing agent; and hydrophobic inorganic fine particles where the magnetic toner particle is a magnetic toner particle obtained by an emulsion condensation method, the binder resin primarily comprises at least a polyester resin, and when precipitation volume of the magnetic iron oxide at an isopropyl alcohol precipitation test is V<SB>IPA</SB>, the precipitation volume of the magnetic iron oxide at the ethyl acetate precipitation test is V<SB>EtA</SB>and a total volume up to the liquid level of ethyl acetate is v<SB>EtA</SB>, V<SB>IPA</SB>/V<SB>EtA</SB>is 1.2 to 3.0 and V<SB>EtA</SB>/v<SB>EtA</SB>is 0.2 to 0.7. COPYRIGHT: (C)2011,JPO&INPIT
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