Polyurethane-encapsulated particle comprising polyol derived from aromatic amine-based initiator
US7416785B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 26, 2004 |
| Grant date | Aug 26, 2008 |
| Priority date | — |
| Expiry date | May 26, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2998
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
An encapsulated particle includes a core particle. The core particle includes a fertilizer selected from the group of nitrogen, phosphate, potash, and sulfur, and combinations thereof. The core particle may also include herbicides, insecticides, and fungicides. The encapsulated particle also includes a polyurethane layer disposed about the core particle. The polyurethane layer includes the reaction product of an aromatic isocyanate component and a polyol that is reactive with the aromatic isocyanate component. The aromatic isocyanate component includes methylene diphenyl diisocyanate, toluene diisocyanate, and mixtures thereof. The polyol that is reactive with the aromatic isocyanate component is derived from an aromatic amine-based initiator and includes a toluene diamine. The aromaticity of the aromatic isocyanate component and the polyol serves to insure complete miscibility between the aromatic isocyanate and the polyol thereby forming the polyurethane layer without defects preventing water from permeating the polyurethane layer and dissolving the core particle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.