Stable ureaform dispersion fertilizers
US4578105A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 7, 1985 |
| Grant date | Mar 25, 1986 |
| Priority date | — |
| Expiry date | Jan 7, 2005 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC05G5/30
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A method for producing storage stable ureaform dispersion fertilizers by: reaction of urea and monomethylolurea in aqueous solution at a pH between 3.0 and 4.5 with a temperature between 25.degree. and 75.degree. C. until between 15 and 40 percent of the total nitrogen has been converted to form a dispersion of finely divided water insoluble ureaform particles; neutralizing; and admixing a water-insoluble, film-forming oil until the dispersed ureaform particles are coated with sufficient oil to prevent contact between the ureaform particles and the aqueous solution. The water insoluble, film-forming oils found effective include fatty acids, fatty acid esters, castor oil, castor oil esters, alkoxylated castor oils, and alkoxylated alkyl phenols. The amount of film-forming oil required to coat the ureaform particles is between 0.1 and 1.0 percent of the aqueous ureaform dispersion. To prevent settling of the coated ureaform particles a xanthan gum, or iota carrageenan thickener is added.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.