PROBLEM TO BE SOLVED: To provide an aqueous suspension agent for directly applying to flooded rice paddies, which is excellent in the suspension stability of the agent and in the diffusivity of a herbicidally active ingredient in water on application, therefore does not have defects such as the generation of crop injuries in paddy rice and the change of a herbicidal effect, does not deteriorate the herbicidal effect in the central portion of a rice paddy, even when the agent is applied from a levee, requires only to be dropped from the levees of a rice paddy without requiring to be applied from places in the rice paddy, even when the rice paddy is large, reduces labors for application works, and is also excellent in economical efficiency.SOLUTION: Provided is the aqueous suspension agent for directly applying to flooded rice paddies, characterized by comprising a herbicidally active ingredient having a water solubility of &le100 ppm at 20°C, a wet method silica calcination product having an average particle diameter of 1 to 10 &mum, a surfactant, and water.COPYRIGHT: (C)2010,JPO&INPIT【課題】本発明は、製剤の懸濁安定性および散布時における除草活性成分の水中拡散性が優れるため、水稲に薬害が発生したり、除草効果が変動するという欠点がなく、また、畦畔から散布しても水田の中央部で除草効果の低下がみられず、大型水田でも畦畔から滴下するのみで水田内に入って散布する必要もなく、散布作業労力が軽減され、経済効率の点でも優れる湛水下水田の直接散布用水性懸濁製剤を得るにある。【解決手段】20℃における水溶解度が100ppm以下である除草活性成分、平均粒子径が1~10μmである湿式法シリカの焼成品、界面活性剤及び水を含有することを特徴とする構成要件とで、湛水下水田の直接散布用水性懸濁製剤を構成している。【選択図】なし
