Flammability and Solder Resistance of Flame Retardant Paper-Base Phenol Laminate

Abstract

Many kinds of flame retardant, copper-clad paper base phenol laminate are now commercially available. But flame retardant, paper base phenol laminates have generally poor resistance against solder. The main cause for such poor solder resistance of the flame retardant (FR) laminates is considered to be the usage of additive type flame retardant agents. Authors investigated a method to improve the solder resistance and flammability of laminates by using reactive type flame retardant agents (P-Bromophenol), TCP and water soluble phenol.
The results of the experiments were as follows.
1. For the cotton linter paper base FR phenol laminate containing 5% wt of Sb₂O₃ and 20% wt p-bromophenol,
(1) Flammability UL 94V-1
(2) Solder resistance 26sec
2. For the kraft paper base FR phenol laminate containing 40% wt of p-bromophenol,
(1) Flammability 94V-0
(2) Solder resistance 18sec