Patent ID: 6733944
Filing Date: 2004-05-11
Classification: G03G

Abstract:
An image forming process comprising the steps of:forming a latent image on a surface of an electrostatic latent image-bearing body; developing the latent image with a toner for developing an electrostatic latent image to form a toner image; transferring the toner image onto a receiving body; and fixing the toner image to the receiving body, wherein the step of fixing is carried out using a fixing device comprising a heat-fixing roller in which a heat-resistant elastic layer is provided on a cylindrical core metal and the resultant surface thereof is further provided with a heat-resistant resin layer, an endless belt, and a pressure member arranged inside the endless belt to allow the endless belt to travel around the heat-fixing roller at a given angle such that a nip is produced through which the receiving body passes, with the pressure member being pressed via the endless belt against the heat-fixing roller at the nip to thereby distort the heat-resistant elastic layer in the heat-fixing roller, and the toner for developing the electrostatic latent image satisfies the requirements of a) a shape coefficient SF1 ranges from 125 to 140 and a shape coefficient SF2 ranges from 105 to 130, wherein SF1=(&pgr;/4)Ã—(L2/A)Ã—100 and SF2=(Â¼&pgr;)Ã—(I2/A)Ã—100, in which L represents a maximum length, I represents a circumferential length and A represents a projected area of toner particles, b) an exposure ratio of a releasing agent at the surface of the toner particles determined by X-ray photoelectron spectroscopy (XPS) ranges from 11 to 40%, and c) a melting point of the releasing agent contained at 8 to 20% by mass in the toner, measured with a differential scanning calorimeter, ranges from 70 to 130Â° C., and the size of the releasing agent determined at a cross section of the toner particle observed with a transmission electron microscope ranges from 150 to 1500 nm.