When the multi-layer board is laminated, the inner core board needs to be processed. The processing technology includes black oxidation treatment and browning treatment. The oxidation treatment is to form a black oxide film on the inner copper foil, and the browning treatment process is to form an organic film on the inner copper foil.

Finally, when laminating, you need to pay attention to the three major issues of temperature, pressure, and time. The temperature is mainly to pay attention to the melting temperature and solidification temperature of the resin, the set temperature of the hot plate, the actual temperature of the material and the speed change of the temperature rise, etc. These parameters need to be paid attention to. As for the pressure, the basic principle is to fill the voids between the layers with resin and exhaust the gas and volatiles between the layers. Time parameters mainly include the control of pressurization timing, the control of heating timing, and gel time.