POWDER ANTIFOAMING AGENT AND METHOD FOR PRODUCING SAME

摘要

Disclosed is a powder antifoaming agent containing: (A) a hydrophobic organopolysiloxane that has a viscosity at 25° C. of 10-100,000 mm2/s; (B) a fine silica powder; (C) a surfactant; and (D) a water-soluble encapsulating agent that is in a solid state at 25° C. This powder antifoaming agent is characterized by being obtained by spray drying a dispersion liquid that is obtained by dispersing a silicone oil compound, which is obtained by mixing the component (A) and the component (B), and the component (D) in water in the presence of the component (C), and is also characterized in that the silicone oil compound is encapsulated by the component (D) that serves as an outer shell. Since the present powder antifoaming agent does not contain water by being produced by a spray drying method, the powder antifoaming agent is free from problems of emulsion antifoaming agents such as separation and putrefaction.

主权项

1. A powder antifoaming agent comprising
(A) a hydrophobic organopolysiloxane having a viscosity of 10 to 100,000 mm2/s at 25° C., (B) finely divided silica, (C) a surfactant, and (D) a water-soluble encapsulant which is solid at 25° C., wherein the powder antifoaming agent is prepared by mixing components (A) and (B) to form a silicone oil compound, dispersing the silicone oil compound and component (D) in water in the presence of component (C), and spray drying the water dispersion, the silicone oil compound being encapsulated in a shell of component (D).