Patent ID: 7759418

Claim:
A flame retardant composition comprising: (A) a phenol-based resin which has an area fraction (a) with a weight average molecular weight in polystyrene equivalent of 870 or more and an area fraction (b) with a weight average molecular weight in polystyrene equivalent of less than 870, the area fraction (a) being 74% or more and 98% or less based on the total 100% of the area fractions (a) and (b), and has a weight average molecular weight in polystyrene equivalent of 2,000 to 80,000, the weight average molecular weight in polystyrene equivalent being measured with a gel permeation chromatography using a tetrahydrofuran as a solvent at a column temperature of 35° C. at a flow rate of 1 mL/min; and (B) a phosphor compound (excluding non-condensed phosphoric ester) comprising a phosphazene compound with a cyclic trimer content of 76 wt % or more, wherein the component (A) is a novolac-type phenol resin that contains a tri-nuclear complex component in an amount of 7% or less.