To obtain an additive capable of improving cold fluidity and lubricity of a fuel oil and effective even by addition thereof in a small amount.
This additive comprises (A) 10-95 wt.% of one or more kinds of oil-soluble amphiphilic media represented by general formula (1) and/or general formula (2) R1-X-R2 (2) [R1 is a 1-50C alkyl, a 1-50C alkenyl, a 1-50C hydroxyalkyl or an aromatic residue; X is NH, NR3, O or S; y is 1-4; and R2 is H or OH and a 2-10C alkyl residue] and (B) 5-90 wt.% of one or more kinds of copolymers comprising (B1) 5-80 mol% of a structural unit derived from an olefinically unsaturated compound having ≥1 free hydroxyl groups and (B2) 20-95 mol% of a structural unit derived from an olefinically unsaturated compound having a ≥6C hydrocarbon group. The copolymers have 500-100,000 g/mol average molecular weight Mw and 10-350 mg (KOH)/g OH value.
REIMANN WERNER
