| 摘要 |
The invention disclosed herein provides a solid silicone defoaming agent which comprises: (A) 5 to 60 weight parts by weight of a selfemulsifying defoaming agent compound and (B) 95 to 40 weight parts wax; wherein said self-emulsifying defoaming agent (A) consists of; at least 5 weight % of a silicone oil compound comprising: (a) a silicone oil having a viscosity of at least 20 centistokes at 25 degrees Centigrade, (b) microparticulate silica, (c) at least 30 weight % of a polyoxyalkylene and/or polyoxyalkylene/polysiloxane copolymer, and optionally (d) zero to 30 weight % of a water soluble surfactant other than copolymer (C): and wherein said wax (B) consists of: (i) wax which does not disperse or dissolve in water at room temperature and which has a melting point of at least 35 degrees Centigrade, and/or (ii) wax which dissolves or disperses in water at room temperature and which ha a melting point of at least 30 degrees Centigrade; and wherein the wax (i) comprises not more than 60 weight % of the overall defoaming agent.
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