Patent ID: 6064850
Filing Date: 2000-05-16
Classification: G03G

Abstract:
An image formation apparatus comprising:a switch configured to selectively set said image formation apparatus in an ON mode in which power is supplied to said image formation apparatus, or in an OFF mode in which power supply to said image formation apparatus is terminated;an image forming unit configured to form a toner image on a sheet;an image fixing unit configured to thermally fix said toner image to said sheet at a predetermined image fixing temperature, said image fixing unit including (a) a rotatable image fixing member, and (b) a heater configured to heat said rotatable image fixing member, said rotatable image fixing member including an exothermic phase transition layer and having a contact surface which contacts said toner image when said toner image is thermally fixed to said sheet, said exothermic phase transition layer including an exothermic phase transition material which performs reversible phase transition from an amorphous solid state to a crystalline state and vice versa and crystallizes at a crystallization temperature which is lower than said predetermined image fixing temperature, with liberation of crystallization heat therefrom, said exothermic phase transition material having a melting point higher than said predetermined image fixing temperature, thereby additionally increasing a temperature elevation rate before a temperature of said contact surface of said image fixing member reaches said predetermined image fixing temperature; anda controlling unit configured to control the temperature of said rotatable image fixing member such that in said ON mode, the temperature of the contact surface of said image fixing member reaches said predetermined image fixing temperature, by heating said exothermic phase transition material to cause said exothermic phase transition material to liberate said crystallization heat therefrom, thereby additionally increasing the temperature elevation rate before the temperature of said contact surface of said image fixing member reaches said predetermined image fixing temperature, and in said OFF mode, said heater heats said exothermic phase transition material to perform the phase transition from said crystalline state to a fused state, and then to terminate the heating, allowing said exothermic phase transition material to cool to change from said fused state to a solid amorphous state.