Patent ID: 7150953

Claim:
A developer comprising a toner particle which comprises a binder resin and a colorant, an inorganic fine particle, and a conductive fine particle, wherein a volume average particle diameter Da of the conductive fine particle and a number average primary particle diameter Db of the inorganic fine particle satisfy the following expression (1): Da≧10Db (1), a rate of liberation “a” of the conductive fine particle from the toner particle is 75 to 88% and a rate of liberation “b” of the inorganic fine particle from the toner particle is 0.80 to 1.90% and when a wettability of the developer with respect to a methanol/water mixed solvent is measured by using, as an index of the wettability, a transmissivity of light having a wavelength of 780 nm through the mixed solvent, a methanol concentration in the mixed solvent at the transmissivity of 80% is in a range of 35 to 80% by volume, wherein the conductive fine particle comprises tin oxide and the inorganic fine particle comprises dry silica treated with silicone oil.