Difficulties in drilling production when producing Flex rigid PCB：
The multi-layer board uses high Tg or other special plates, and the roughness of the drilling of different materials is different, which increases the difficulty of removing the slag in the hole. High-density multi-layer boards have high hole density and low production efficiency, which is easy to break. Between the via holes of different networks, the edge of the hole is too close to cause the CAF effect problem.
Suggestion: The hole edge spacing of different networks is ≥0.3mm