(1) A conductor layer is disposed on at least one surface of a dielectric layer, the dielectric layer including an intermediate layer and a pair or more of fluororesin layers disposed on both surfaces of the intermediate layer, in which the ratio of the total average thickness of the intermediate layer to the total average thickness of the fluororesin layers is 0.001 to 30, the relative dielectric constant of the intermediate layer is 1.2 to 10, the coefficient of linear expansion of the intermediate layer is −1×10−4/° C. to 5×10−5/° C., and the adhesive strength between the fluororesin layer and the conductor layer is 300 g/cm or more. (2) Conductor layers are disposed on both surfaces of a dielectric layer made of a fluororesin, in which at least one of the conductor layers constitutes a wiring pattern, the average trace width of the wiring pattern is 25 to 300 μm, the average thickness of the dielectric layer in the region where traces of the wiring pattern are disposed is 5 to 125 μm, and the ratio of the average trace width to the average thickness of the dielectric layer is 2.4 to 30. (3) A multilayer structure includes conductor layers and dielectric layers made of a fluororesin alternately disposed, in which the fluororesin of the dielectric layers is crosslinked and chemically bonded to the conductor layers, the average thickness of the multilayer structure is 30 to 2,000 μm, and the crush resistance of the multilayer structure measured by a loop stiffness test is 0.1 to 20,000 N/cm.