Patent ID: 7390603

Claim:
An image forming apparatus comprising: a negatively chargeable spherical toner; a latent image carrier; a charging member for charging a surface of the latent image carrier uniformly without contacting the latent image carrier; a cleanerless electrostatic latent image forming member for forming an electrostatic latent image on the surface of the latent image carrier; a developing member for developing the electrostatic latent image, without contacting the latent image carrier, by using the negatively chargeable spherical toner so as to form a toner image on the latent image carrier; and an intermediate transfer medium to which the toner image is transferred, wherein the negatively chargeable spherical toner comprises: a toner mother particle comprising a binder resin and a colorant; and a hydrophobic alumina particle as an external additive, wherein the hydrophobic alumina particle has a work function (Φ A1 ) larger than a work function (Φ TM ) of a surface of the intermediate transfer medium.