PURPOSE: An inexpensive photo-setting composition usable for vehicles of coating materials and inks, without causing dermatitis, comprising an air-oxidizable polymerizable composition and a condensed aromatic ring compound.

CONSTITUTION: A composition comprising (A) an air-oxidizable polymerizable composition, e.g. vegetable fats and oils such as tung oil, or unsaturated fatty acids or their derivatives, and (B) (a) 0.1W30wt% of a condensed aromatic ring compound, e.g. naphthalene, (b) 0W10wt% calculated as metal of a metal salt of a fatty acid, e.g. cobalt naphthenate, and (C) 0W30wt% of a coloring matter, e.g. Methylene Blue.

EFFECT: Improved storage stability.