Controlled release plant nutrients
US5803946A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 1996 |
| Grant date | Sep 8, 1998 |
| Priority date | — |
| Expiry date | Jun 20, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC05C9/005
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Plant nutrients that are released in soil over a controlled period of time are comprised of plant nutrient particles containing urea and on the surface of the particles a water insoluble, biodegradable, interpenetrating polymer network comprised of a biuret, a urethane and tung oil; more specifically, an interpenetrating network comprised of the reaction product of the urea and an isocynate reactive with urea, the reaction product of the isocyanate and an alcohol reactive with isocyanate to form a urethane, and the reaction product of the urethane and tung oil. A method of making the controlled release plant nutrient conveniently and economically is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.