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