| 摘要 |
PROBLEM TO BE SOLVED: To obtain a granular defoaming agent compsn. which does not solidify at high temp. and humidity, does not undergo the degradation in powder characteristics, and has been improved in storage stability, capability for releasing a defoaming agent in water, and dispensability in water by incorporating a hydrocarbon wax defoaming agent and a natural starch and/or a cold-water- insoluble modified starch into the same. SOLUTION: (A) 0.5-40 wt.%, pref. 1-35 wt.%, hydrocarbon wax defoaming agent which has an m.p. of 25-135 deg.C and is a petroleum wax such as a paraffin wax mainly comprising 20-40C straight-chain hydrocarbons extracted from a petroleum lubricant fraction or a microcrystalline wax mainly comprising 30-60C non-straight-chain hydrocarbons extracted from a petroleum heavy lubricant fraction or is a Fischer-Tropsch wax mainly comprising 17-78C hydrocarbons or polyethylene wax and (B) 6-20 wt.%, pref. 5-50 wt.% natural starch and/or modified starch insoluble in water at 25 deg.C or lower are compounded in a wt. ratio of A/B of 0.1-2.0. |
