PURPOSE: The titled industrially useful composition having improved filler dispersibility, thixotropic properties, and weather resistance, comprising a high polymer substrate, a flame-retardance imparting filler, a specific fatty acid and polyether as essential components.

CONSTITUTION: (A) A high polymer substance is blended with (B) a flame- retardance imparting filler (e.g., alumina, aluminum hydroxide, or antimony trioxide), (C) (i) 6W22C fatty acid alkanol amide or an adduct of it with an alkylene oxide, and (ii) a polyether compound, an adduct of a compound (e.g., polyethyleneimine) containing ≥3 active hydrogens with an alkylene oxide, containing 0W80wt%, preferably 3W40wt% oxyethylene group based on total molecular weight, having 1,000W1,000,000 molecular weight, as essential components, to give the aimed composition. A weight ratio of the component i/B is preferably 3/7W7/3.