| 摘要 |
PURPOSE: To obtain microcapsules secured in storage stability and encapsulating a water-insoluble pesticide by dispersing a solution of a polyisocyanate in a hardly water-soluble pesticide in water and reacting the dispersed solution with a polyamine in the presence of a water-dispersible nonionic surfactant having a hydrophobic block and a hydrophilic block. CONSTITUTION: The nonionic surfactant having 1,000-250,000 dalton average molecular weight and a block structure shown by A-B-A, A-B or (A-B)n (wherein (n) is an integer of 1-5; A is at least one hydrophilic block; B is at least one hydrophobic block) is dissolved in water, where the polyisocyanate solution obtained by dispersing it in the solution of the pesticide compound is added and then the polyamine is added while mixing and the resultant solution is further mixed at 20,000 rpm by a high shear mixer until the polyamine is completely mixed with the polyisocyanate. A high concentration active component is attained without using a sulfonating agent by this method. |
