Patent ID: 8669495
Filing Date: 2014-03-11
Classification: G03G,H05B

Abstract:
1. An image heating apparatus for heating an image formed on a recording material, comprising: a heater including a ceramic substrate, wherein at least two first heat generating resistors and at least one second heat generating resistor are formed on a first surface of the substrate along a longitudinal direction thereof, and the second heat generating resistor is provided between the first heat generating resistors in a direction of a shorter side of the substrate; wherein the second heat generating resistor includes a first region having a low resistance value per unit length and a second region having a resistance value per unit length higher than the resistance value of the first region; a first switching element, which is connected electrically between a power source and said first heat generating resistors, for controlling an electrical power supply to said first heat generating resistors; and a second switching element, which is connected electrically between the power source and said second heat generating resistor, for controlling an electrical power supply to said second heat generating resistor; wherein said heater has a substrate-reinforcing layer only along a portion of the longitudinal direction in a second surface opposite to the first surface of the substrate, and wherein the substrate-reinforcing layer is formed by coating the second surface with a material having thermal conductivity higher than a thermal conductivity of the substrate and an area of the substrate-reinforcing layer regarding the longitudinal direction includes all the second region of the second heat generating resistor, and at least a part of the first region of the second heat generating resistor is not included in the area of the substrate-reinforcing layer.