Microencapsulated polymorphic agriculturally active material
US5160530A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 1989 |
| Grant date | Nov 3, 1992 |
| Priority date | — |
| Expiry date | Jan 24, 2009 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA01N33/18
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Agriculturally active materials, such as pesticides, herbicides and the like and a process for microencapsulating said materials. The present invention includes trifluralin having a polymorphic form characterized by a yellow color and a melting point of approximately 41.degree.-43.degree. C. The present invention also includes a method of using the yellow polymorphic form of trifluralin as a herbicide. In addition, the present invention includes a method of microencapsulating low-melting agriculturally active materials, such as trifluralin. The microencapsulation process comprises the steps of heating a low-melting, water-immiscible, agriculturally active material to a molten state. The molten active material is then combined with an aqueous soluion of a water-soluble, film-forming polymer at a temperature sufficient to maintain the active material in its molten state. The active material is then dispersed or emulsified in the aqueous solution so that the active material has a primary particle size of between approximately 0.1 and 10 microns. The resulting dispersion or emulsion is then spray dried at a temperature between approximately 50.degree. and 220.degree. C., so as to micro…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.