It is an object to form a conductive intermediate layer having a function of maximally preventing a solder leaching phenomenon with a low environment load and with good productivity.There are provided an insulative base material 2, a wiring circuit pattern 3 formed on at least one surface of the insulative base material 2, an electronic part mounting land 31 which is formed as part of the wiring circuit pattern 3 and on which an electronic part 7 is to be mounted, and a conductive intermediate layer 5 made of a sintered conductive ink film on the electronic part mounting land 31.