Alcohol defoamers are rapid-acting antifoaming agents utilizing low-carbon chain alcohols (e.g., ethanol, isopropanol) or high-carbon chain alcohols (e.g., octanol, stearyl alcohol) as primary active components. Their defoaming mechanism relies on alcohol molecules rapidly spreading and penetrating foam film surfaces, effectively reducing local surface tension to disrupt foam mechanical equilibrium, while displacing foam-stabilizing molecules to accelerate film thinning and rupture. These defoamers offer advantages including immediate action, easy application, and minimal residue, making them particularly suitable for temporary situations requiring quick surface foam elimination. Widely used in pulp/paper manufacturing, coating production, printing inks, and adhesive manufacturing processes, they provide instant foam suppression without altering fundamental system properties. However, their foam prevention persistence is limited, requiring repeated additions in continuously foaming systems, with additional flammability concerns for some low-boiling-point alcohols necessitating careful selection based on specific process conditions.