Emulsion defoamers are stable oil-in-water emulsion systems formed by uniformly dispersing highly efficient defoaming active ingredients (such as polysiloxanes and hydrophobic particles) into an aqueous phase through specialized emulsification processes. Their core advantage lies in combining the easy dispersibility of aqueous systems with the powerful defoaming capability of oil-based components: when the emulsion is added to a foaming system, the emulsified particles rapidly release active substances upon de-emulsification. These substances utilize their low surface tension to spread quickly across bubble films, achieving highly efficient foam collapse by disrupting film elasticity and promoting drainage. This defoamer category offers convenient application, rapid dispersion, and persistent action, with the added benefit of precisely tunable compatibility and defoaming speed through emulsion system adjustments. Widely used in aqueous systems across papermaking, textiles, coatings, and petroleum extraction industries, they effectively eliminate surface foam and micro-bubbles while avoiding defects like oil spots and fish eyes.