NYA FENOLHARTSBLANDNINGAR.

摘要

1. Phenolic resin compositions suitable for the manufacture of phenolic prepreg mats, according to which the compositions employed for impregnating the fibre mats consist of phenolformaldehyde resins of the resole type, fillers, pigments and hardening agents, characterized in that these compositions contain an additive consisting of at least 20% by weight of an alkali or alkaline-earth metal metaborate relative to the total weight of the additive, the additive being used in a quantity equal to at least 5% and not exceeding 60% by weight relative to the weight of the solution of phenolic resin.