Manufacturing process of PCB (Printed Circuit Board)

Abstract

The invention relates to a manufacturing process of a PCB (Printed Circuit Board), in particular to a soldmask hole-plugging procedure of the PCB. The manufacturing process comprises the steps of: (1) soldmask pretreatment; (2) ink hole plugging of a PCB; (3) prebaking; (4) exposure; (5) development; (6) appearance inspection (7) UV (ultraviolet light irradiation) of the PCB for curing ink for hole plugging; and (8) postcuring of the PCB. According to the manufacturing process, the step of UV light irradiation is added to the soldmask hole plugging procedure of the PCB, thereby not only achieving a strong light curing effect on the ink in the plugging hole of the PCB, but also better curing the soldmask ink on the surface of the board; and the problem of popping in the post procedure can be effectively avoided, the falling of the soldmask ink on the surface of the board in the post procedure is prevented, the product quality of the finished PCB can be guaranteed, and the production efficiency is improved.

Description

technical field [0001] The invention relates to the field of PCB production, in particular to the solder-proof plug hole process of the PCB board. Background technique [0002] Modern electronic products are increasingly developing in the direction of miniaturization, high integration, and high performance, and the design of printed circuit boards is becoming more and more difficult. The design of PAD points tangent and intersecting with holes on the circuit board is relatively increased. The above structure needs to plug the via holes on the circuit board to avoid solder beads flowing to the opposite side through the holes during wave soldering, affecting the performance of components or Cause a short circuit; In addition, the plug hole can also protect the via hole, reduce or delay the corrosion of the hole wall in the board application. According to statistics, general PCB manufacturers need plugged holes for their circuit board products, accounting for more than 85% of ...

AI Technical Summary

Problems solved by technology

[0003] In the existing plugging process, after plugging, the ink in the hole is dried by baking to avoid its flow, but the baking method can only dry the solder resist oil layer on the surface of the plug hole, and the ink in the center of the hole remains before post-curing. In a fluid state, the properties and viscosity of different types of inks and the high-temperature baking in the post-curing step will directly cause the plugging ink to expand and pop out due to heat, forming a bad phenomenon of ink bursting

Aiming at the blowout phenomenon, the industry has introduced many improvement measures, such as canceling the problematic plug hole, modifying the problematic FILM, secondary exposure, etc., but it still cannot completely improve the blowout problem