Dear fellows: Can somebody explain me a theory(chemistry) of the soldrablility reduction during PCB baking? We are baking the PCB assy prior to the wave soldering process. The board laminate is special nylon material and has gold over the bare copper pads. The time between baking and soldering is 48 hours. ( 2 hours, 135 degree C). When production can not keep up, they rebake the PCB assy again for the second time. I have read, that each temperature exposure reduces the solderabilty of the PCB. Is it correct? Why? Thank you, Sincerely Stella Neyman