Abstract: The invention provides novel additives which are useful as defoaming and anti-popping agents, or flow-and-leveling agents, for paints and inks. When the additives are blended with paints which do not use melamine resins as the curing agent, they can impart defoaming property and flow-and-leveling property to the paints without inviting white blooming or turbidity in the painted films caused by infiltration of water. Hence the additives are particularly useful when used for clear paints. The additive is characterized in that it comprises a copolymer of 2-50% by weight of a reactive monomer having isocyanate group or an isocyanate-derived group with 98-50% by weight of other monomer or polymer reactable with said reactive monomer.