Polymer-based, VOC- and silicone-free defoamer for aqueous coatings, printing inks, adhesives, paper coatings and construction chemicals. Optimum performance at the lowest dosage. Suitable for applications that come into contact with food. BYK-1640 is a very versatile defoamer for aqueous systems. The additive is particularly recommended for the production and application of emulsion paints and plasters within a PVC range of 30-85. The additive is free of silicones and mineral oil, and is especially suitable for VOC-free systems. BYK-1640 exhibits optimum performance at the lowest dosage, is stable to acids and alkalis, and can be used in the pH range 3-12. BYK-1640 can be used in aqueous OPVs and internal coatings (pigmented and clear coatings) in the can coatings field. The additive can also be post-added and shows very good compatibility. BYK-1640 has a spontaneous defoaming effect and is also suitable for preventing microfoam. In coil coating systems, BYK-1640 can be used both in the millbase and be post-added. Especially recommended for architectural coatings and coil/can coatings. Also suitable for protective coatings.