MAGNETIC TONER COMPRISING MAGNETIC TONER PARTICLE CONTAINING BINDER RESIN HAVING POLYESTER UNIT AND PREPARED BY USING TITANIUM CHELATE COMPOUND AS CATALYST, AND MAGNETIC IRON OXIDE

摘要

PURPOSE: Provided is a magnetic toner which is excellent in developability and environmental stability and is reduced in toner consumption. CONSTITUTION: The magnetic toner comprises a magnetic toner particle containing at least a binder resin and a magnetic iron oxide, wherein the toner has a saturation magnetization (σ s) of 5-60 Am2/kg at 795.8 kA/m and a residual magnetization (σr) of 0.1-10.0 Am2/kg, and the binder resin contains a polyester unit and is prepared by using a titanium chelate compound as a catalyst. Preferably the titanium chelate compound is any one compound represented by the formulas 1 to 8, wherein R1 and R4 are independently a substituted or unsubstituted C2-C10 alkylene or alkenylene group; R2, R3, R5 and R6 are independently a substituted or unsubstituted C1-C10 alkylene or alkenylene group; M is a counter cation; n is 2 if m is 1 and n is 1 if m is 2; and M is a hydrogen ion, an alkali metal ion, an ammonium ion or an organic ammonium ion if n is 1, and M is an alkaline earth metal ion if n is 2.