| 摘要 |
PURPOSE: To obtain a herbicide composition comprising microencapsulated yellow polymorphic form trifluralin and excellent in storage stability and in dispersibility in water. CONSTITUTION: This herbicide composition comprises the water-soluble microencapsulation product of yellow polymorphic formα,α,α-trifluoro-2,6-dinitro-N,N-di-n-propyl-p- toluidine. The herbicide composition is obtained by heating the low-melting (melting point: 30-130 deg.C), water immiscrible, agriculturally active material to a molten state, combining the molten active material with an aqueous solution of a water-soluble, film-forming polymer at a temperature sufficient to maintain the active material in the molten state, dispersing or emulsifying the active material in the aqueous solution of the water-soluble, film-forming polymer so that the active material has a primary particle size of between approximately 0.1 and 10 microns, and subsequently spray drying the resulting dispersion or emulsion at a temperature between about 50 deg.C and 220 deg.C so as to microencapsulate the active material in the polymer. When the active substance has a high melting point, the active substance is ground until to give a particle size of 0.1-10μm, mixed with the aqueous solution of a water-soluble film-forming polymer and subsequently spray-dried. |
