Study on Swelling Solution for High Tg Epoxy Resin Substrate
A new type of swelling solution is developed, which is applied for the pre-treatment of plating-through-hole (PTH) of print circuit board (PCB) made up of high Tg epoxy resin substrates. The results show that the best formula is 144 organic esters 200g/L and hexylene glycol 2g/L. The treatment temperature and processing time is 60°C and 6min, respectively. Under the optimal conditions, the residue caused by drilling can be removed completely through the process including swelling, oxidation and neutralization.
G. F. Han et al., "Study on Swelling Solution for High Tg Epoxy Resin Substrate", Applied Mechanics and Materials, Vols. 66-68, pp. 90-95, 2011