Flame-retardant resin composition

A flame-retardant resin composition comprising a flame retardant and a polyalkylene arylate-series resin, in which the flame retardant comprises a phosphazene compound and a polyphenylene oxide-series resin,

• wherein the phosphazene compound comprises at least a crosslinked phenoxyphosphazene compound in which at least one phenoxyphosphazene compound selected from the group consisting of a cyclic phenoxyphosphazene compound represented by the following formula (1) and a linear phenoxyphosphazene compound represented by the following formula (2) is crosslinked with the following crosslinking group:
• 7
• wherein m denotes an integer of 3 to 25, and Ph represents a phenyl group;
• 8
• wherein X1 represents the group —N═P(OPh)3 or the group —N═P(O)OPh, Y1 represents the group —P(OPh) 4 or the group —P(O)(OPh) 2, n denotes an integer of 3 to 10,000, and Ph has the same meaning as defined in the formula (1);
• and
• the crosslinking group comprising at least one member selected from the group consisting of o-phenylene group, m-phenylene group, p-phenylene group, and a bisphenylene group represented by the formula (3)
• 9
• wherein A represents —C(CH3)2—, —SO2—, —S— or —O—, and a denotes 0 or 1;
• and
• wherein the crosslinking group is bonded to two oxygen atoms with elimination of phenyl groups of the phenoxyphosphazene compound(s), and the content of the phenyl group of the crosslinked compound is, based on the total phenyl groups in at least one phosphazene compound selected from the group consisting of the phosphazene compounds (1) and (2), 50 to 99.9 mol %, and the crosslinked phenoxyphosphazene compound is free from a free hydroxyl group.