This treatment tool comprises a heat transfer plate 13 and a resistance pattern 162 arranged on a second face 132 of the heat transfer plate 13 and generating heat when energized. When the heat transfer plate 13 is partitioned into a plurality of partition bodies by a second partitioning plane F2, the plurality of partition bodies include a first partition body B1 and a second partition body B2 having a heat capacity lower than that of the first partition body B1. When a second central axis Ax2 is the axis passing through the center position of the second face 132 in the width direction and extending in the length direction thereof, the second partitioning plane F2 is the plane passing through the second central axis Ax2 while being orthogonal to the width direction. The resistance pattern 162 is configured such that a ratio is set between the resistance value in a first partition region Ar1 on the second face 132 constituted by the first partition body B1 and the resistance value in a second partition region Ar2 on the second face 132 constituted by the second partition body B2 according to the heat capacity ratio between the first and second partition bodies B1, B2, and the resistance value in the first partition region Ar1 is higher than the resistance value in the second partition region Ar2.L'invention concerne un outil de traitement comprenant une plaque de transfert de chaleur 13 et un tracé de résistance 162 disposé sur une seconde face 132 de la plaque de transfert de chaleur 13 et générant de la chaleur lorsqu'il est excité. Lorsque la plaque de transfert de chaleur 13 est divisée en une pluralité de corps de partition par un second plan de partition F2, la pluralité de corps de partition comprend un premier corps de partition B1 et un second corps de partition B2 ayant une capacité thermique inférieure à celle du premier corps de partition B1. Lorsqu'un second axe central Ax2 est l'axe passant par la position centrale de la seconde face 132 dans la direct
