US Patent 7376379 Metal belt, fixing belt and heat fixing device

Provided are a metal belt which is improved in wear resistance, thermal conductivity, thin wall designs, heat resistance and flexibility, a fixing belt in which this metal belt is used, and a high durability and high reliability heat fixing device which has this fixing belt. This metal belt is made of a nickel-iron alloy manufactured by an electroforming process, and the nickel-iron alloy satisfies relationships expressed by the following equations:0.001≦S≦0.13, and  (1)85×S+3≦F≦350×S+3  (2)wherein S represents a sulfur content (mass %) and F represents an iron content (mass %).