EMULSION-TYPE DEFOAMING AGENT COMPOSITION AND DEFOAMING METHOD USING THE SAME

摘要

PURPOSE:To obtain an excellent emulsion-type defoaming agent having a defoaming property and capable of preventing pitch formation and environmental pollution by emulsifying a composition contg. specified pts.wt. of org. liq., silicone oil, hydrophobic silica and modified silicone oil in water with an emulsifier. CONSTITUTION:This defoaming agent composition is obtained by emulsifying a composition contg. 5-35 pts.wt. of org. liq., 0.5-5 pts.wt. of silicone oil, 0.5-5 pts.wt. of hydrophobic silica and 1-40 pts.wt. of modified silicone oil with the emulsifier. A liq. paraffin produced by completely hydrogenating mineral oil and having zero iodine value and the dynamic viscosity (40 deg.C) of 12-70cst and a synthetic oil obtained by polymerizing a mixture of alcohols and glycols and propylene oxide or propylene oxide and ethylene oxide are singly or jointly used as the org. liq. The content of emulsifier is controlled to 1-10 pts.wt. This emulsion-type defoaming agent composition is useful as the defoaming agent in water, especially in strong aq. alkali.