to the adhesion between a base film and a metal wiring and the shape of the base film and the metal wiring after the adhesion test is performed as shown in fig3 a copper wiring pattern 310 having 1 cm u00d7 10 cm u00d7 10 u03bcm of width a u00d7 length b u00d7 thickness c was printed on the bismaleimide triazine resin film bt film 300 with ink including copper nanoparticles having an average size of 20 nm by the ink jet method as shown in fig4 after drying the copper wiring pattern 310 formed on the base film a induction heating furnace 430 connected with a high frequency oscillator 410 was passed at an operation frequency of 500 khz by using a conveyor belt 420 nitrogen argon oxygen hydrogen air organic acid gas or alcohol gas etc may be injected to the induction heating furnace 430 through a injection hole and air was used in this example the heating part 440 could be selected from a probe microphone type 470 which is suitable for the induction heating of a small portion of the circuit substrate where the wiring is formed along with the area to be heated and a loop type which is suitable for the entire circuit substrate in this example the probe microphone type heating part was used for the induction heating of the small portion including the copper wiring pattern of the printed circuit board 400 and for sintering with heat instantaneously generated to form a wiring of the printed circuit board its adhesion was determined and summarized.