In the PCB solder resist production process, sometimes encounter ink off the case, the reason can basically be divided into the following three points.
1, PCB in the printing ink, pre-treatment is not in place, such as PCB board surface stains, dust or impurities, or part of the area was oxidized, in fact, to solve this problem is very simple, re-do the pre-treatment again on the line, but we must strive to clean up the circuit board surface stains, impurities, or oxidized layer.
2, baking circuit board short time or temperature is not enough, because the circuit board in the printed heatset ink after baking at high temperatures, and if the baking temperature or time is not enough will lead to the strength of the ink on the surface of the board.
3, ink quality problems or ink expiration date, or procurement of well-known brands of ink, this will also cause the circuit board ink over the tin furnace when dropped.
