Patent ID: 8580903

Claim:
A flame retardant for thermoplastic resins, comprising a reaction product of a nitrogen-containing compound represented by structural formulae (1) and a phosphorus-containing compound represented by structural formula (2), wherein the flame retardant is insoluble in toluene and has a phosphorus atom content of 5 to 10 wt %, and wherein the weight-average molecular weight (Mw) thereof is 2,000-10,000, wherein two or more of R 1 , R 2 , and R 3 are unsaturated bond-containing groups and the other is a hydrogen atom or an organic group other than unsaturated bond-containing groups; and wherein R 4 , R 5 , and R 6 each are independently a hydrogen atom or an alkyl, cycloalkyl, aryl or aralkyl group.