INSULATED WIRE

PROBLEM TO BE SOLVED: To provide an insulated wire capable of suppressing charge degradation under a high temperature environment and increasing a charge life. SOLUTION: The insulated wire T1 includes a first resin layer 1 coating the periphery of a conductor 4 and a second resin layer 2 coating the periphery of the first resin layer 1. The first resin layer 1 has a relative dielectric constant 1; and the second resin layer 2 has a relative dielectric constant 2. The relative dielectric constants 1 and 2 satisfy the relationship of 1/ 2>1 or preferably 1/ 2>1.1 at a temperature of 150°C or higher. The first and second resin layers 1 and 2 are made of substances selected from an amorphous resin whose glass transition temperature (Tg) is 150°C or higher and a crystalline resin whose melting point (Tm) is 150°C or higher. COPYRIGHT: (C)2010,JPO&INPIT