Patent ID: 6045810
Filing Date: 2000-04-04
Classification: C05G

Abstract:
A particulate, controlled release plant food composition resistant to attrition during storage, handling, shipping, and application, comprising:(a) water soluble central particles of plant nutrients, selected from the group consisting of urea, ammonium, nitrate, ammonium phosphate, ammonium sulfate, potassium chloride, potassium nitrate, and potassium sulfate, amounting to between 75 and 98 percent of the plant food composition;(b) water insoluble resin coatings, selected from the group consisting of polyurethanes, isocyanate-polyols, polyalkenes, polystyrenes, and alkyd polymers, amounting to between 2 and 25 percent of the plant food composition, covering the water soluble central particles of plant nutrients; and,(c) water insoluble plant nutrient particles, exhibiting diameters smaller than 50 microns, dispersed in the resin coatings, the nutrient particles being selected from the group consisting of magnesium ammonium phosphate, magnesium potassium phosphate, magnesium phosphate, iron phosphate, and melamine cyanurate, the nutrient particles being formed in-situ by chemical coreaction of a plurality of plant food moieties selected from the group consisting of phosphoric acid, magnesium oxide, potassium hydroxide, ammonium phosphate, cyanuric acid and melamine.