Patent ID: 8824936

Claim:
An image forming method, comprising: charging, by a charging device, a peripheral surface of an image bearing member on which an electrostatic latent image is formed; irradiating the peripheral surface of the image bearing member whose peripheral surface was charged, the irradiating being carried out with a light based on image information and forming an electrostatic latent image on the peripheral surface of the image bearing member by using an exposure device; developing the electrostatic latent image formed on the image bearing member with the toner that has been conveyed by the toner bearing member, and forming a toner image on the image bearing member; using a transfer device to transfer the toner image formed by the developing device to a recording medium; and using a cleaning device to remove the toner remaining on the image bearing member after the transfer, wherein a surface of the toner bearing member is subjected to alumite treatment, the toner is magnetic mono-component developer including magnetic toner particles containing at least binder resin and iron-containing magnetic powder, and an external additive to be externally added to the magnetic toner particles, the external additive is formed from inorganic fine particles which have been subjected to surface treatment with a tin-containing compound and an antimony-containing compound, the external additive is obtained by mixing a solution containing the tin-containing compound and the antimony-containing compound with a dispersion liquid obtained by dispersing the inorganic fine particles in water, a blending quantity of the tin-containing compound is 6 to 15 parts by mass relative to 100 parts by mass of the inorganic fine particles, a blending quantity of the antimony-containing compound is 2 to 10 parts by mass relative to 100 parts by mass of the inorganic fine particles, a mixed solution obtained by mixing the solution containing the tin-containing compound and the antimony-containing compound with the dispersion liquid has a pH of 2 to 4, and the ratio of antimony to iron of the toner that has been removed by the cleaning device is double or more the ratio of antimony to iron of the toner before being conveyed by the toner bearing member.