Dimensionally stable phenolic resin circuit board base material - contg. resin modified with brominated oil as flame retardant and reactive unsatd. hydrocarbon

摘要

Dimensionally stable PF (phenol/HCHO resin) circuit board base material (I) consist of cellulosic material impregnated with PF resins (II) contg. oil-modified flame retardant, which is dried, laminated and cured using pressure and heat. The novel features are that (a) (II) is produced by treating phenolic raw material (III) with an oil component (IV) contg. bromine and, immediately after this, with a 1-100, pref. 50(wt.)% unsatd. reactive hydrocarbon (V) w.r.t. (IV) and alkylating at 333-373 K in the presence of an acid catalyst (VI), pref. strong aromatic sulphonic acid, so that all other (IV) components and (V) are reacted completely, then condensing the adduct with HCHO, a basic catalyst and opt. other (III); (b) the (II) fraction is 45-60% w.r.t. (I); and (c) cure is carried out in the usual way at 420-460 K. USE/ADVANTAGE - (I), which is useful in the electrical and electronics industry, has good dimensional stability and dielectric characteristics. (V) increase the storage stability of (IV). (I) also has low water absorption and good stamping properties at room temp. and is hardly flammable (UL 94 rating VO).