| 摘要 |
A positively charged toner that comprises a plurality of toner particles provided with a core and a shell layer formed on the core surface. The core comprises a polyester resin. The shell layer covers 40-80% inclusive of the surface area of the core. When the zeta potentials of the positively charged toner, said positively charged toner being in a state where the toner particles contain no external additive, measured in an aqueous medium at pH 3, 4, 6 and 7 are referred to as ζ(3), ζ(4), ζ(6) and ζ(7) respectively, ζ(4) is higher than 0 V, ζ(6) is lower than 0 V, and the requirement │ζ(3)-ζ(4)│>│ζ(6)-ζ(7)│ is satisfied. |
