HEATER AND IMAGE HEATING DEVICE HAVING THE SAME

PROBLEM TO BE SOLVED: To provide a heater, wherein the exothermic distribution of a heating resistor is made uniform and a temperature difference between a paper passage region through which recording material passes and a paper non-passage region through which the recording material does not pass, is reduced. SOLUTION: The heating body has a first electrode 21 provided in a longitudinal direction of a substrate 14 on one end side in a width direction orthogonal to the longitudinal direction of the substrate 14, and a second electrode 22 provided in the longitudinal direction of the substrate on the other end side in the width direction orthogonal to the longitudinal direction of the substrate. Assuming that, in the electrodes 21 and 22: length in the longitudinal direction of the substrate in second regions 21b and 22b is L1(m); cross section in the width direction of the substrate in the second regions is S1(m2); length in an energizing direction of the heating resistor 15 is L2(m); cross section in the longitudinal direction of the substrate of the heating resistor is S2(m2); volume resistivity value of the second region when heating an image on the recording material is A1(Ωm); and volume resistivity value of the heating resistor when heating the image on the recording material is A2(Ωm), A1≤A2×S1×L2/(29.4×S2×L1) is satisfied. COPYRIGHT: (C)2009,JPO&INPIT