Patent · US Expired

Process for the preparation of microcapsules

US5866153A · kind A · utility

18Cited by
8References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 8, 1995
Grant dateFeb 2, 1999
Priority date
Expiry dateAug 8, 2015

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01J13/16
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The invention relates to a process for the preparation of an aqueous suspension of microcapsules having a capsule wall of polyurea and encapsulating a water-immiscible pesticide, by dispersing a solution of a polyisocyanate in the sparingly water-soluble pesticide in water and subsequently reacting the dispersion with a polyamine, which process comprises effecting the dispersion of the solution of the polyisocyanate in the sparingly water-soluble pesticide in water and the subsequent reaction of the dispersion with the polyamine in the presence of at least one water-soluble or water-dispersible nonionic surfactant of a block copolymer having at least one hydrophobic block and at least one hydrophilic block.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.