Flame-retardant resin composition

A flame-retardant resin composition which comprises:

• 10 to 30 parts by weight of a flame-retardant composition comprising an aromatic phosphoric acid ester shown by the following formula (I);
• ##STR3## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently represent a phenyl group substituted with 0 to 3 alkyl groups each having 1 to 3 carbon atoms, A represents a 1,3-phenylene group and n denotes an integer of 0 to 5;
• R.sup.1, R.sup.2, R.sup.3 and R.sup.4 comprise at least (a) a 2,4-dimethylphenyl group, a 3,4-dimethylphenyl group or a 3,5-dimethylphenyl group and (b) a monoalkylphenyl group;
• and the proportion of the amount of the 2,4-dimethylphenyl group, the 3,4-dimethylphenyl group and the 3,5-dimethylphenyl group relative to the amount of the monoalkylphenyl group in R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is such that the former/the latter is 60/40 to 90/10 (mole percent) wherein 0 to 10 mole percent has the repeating unit n of 0, 40 to 90 mole percent has the repeating unit n of 1, 5 to 40 mole percent has the repeating unit n of 2 and 5 to 25 mole percent has the repeating unit of n of not less than 3;
• 0. 1 to 2 parts by weight of polytetrafluoroethylene (D);
• and
• 100 parts by weight of a mixture of thermoplastic resins comprising 50 to 90% by weight of an aromatic polycarbonate resin (A) and 10 to 50 % by weight of a stytonic resin (B).