Controlled release agricultural products and processes for making the same

Abstract

A controlled release agricultural absorbent based product including particles of an absorbent material containing capillaries/voids between 10-200 microns in cross-sectional diameter which is impregnated in an amount of 40-95% of the capillaries/voids volume with an agriculturally beneficial material selected from the group consisting of fertilizers, insecticides, herbicides and fungicides, being produced by a process including steps of 1) introducing water to particles of absorbent material to result in absorption of water within the absorbent material, 2) heating the absorbent particles and water to transform the water within the absorbent particles to steam, 3) introducing the heated absorbent particles to an agriculturally beneficial material in aqueous solution to essentially saturate the absorbent particles with the agriculturally beneficial material, 4) granulating the combination of agriculturally beneficial material and saturated absorbent particles to solidify and harden the mixture, resulting in the agglomeration of absorbent particles into granules, and 5) drying the granules.

1 - 98 . (canceled) 
   
   
       99 . A controlled release agricultural product comprising: 
     a mixture of a control release holding substance selected from the group consisting of plant starches, protein gels, glues, gumming compositions, crystallizing compounds, gelling clays and synthetic gel forming compounds; 
     and an agriculturally beneficial material selected from the group consisting of fertilizers, insecticides, herbicides and fungicides, said agricultural product being in a particulate form. 
   
   
       100 . The controlled release agricultural product of  claim 99  wherein the holding substance is 4-8% wt of the agricultural product. 
   
   
       101 . The controlled release agricultural product of  claim 99  wherein the holding substance is a starch selected from the group consisting of corn starch, rice starch, potato starch, wheat starch, tapioca starch, starch containing D-glucopyranose polymers, amylose and amylopectin. starch acetates, starch esters, starch ethers, starch phosphates 
   
   
       102 . The controlled release agricultural product of  claim 99  wherein the interspatial blocker is corn starch or wheat starch. 
   
   
       103 - 109 . (canceled) 
   
   
       110 . The controlled release agricultural product of  claim 99  wherein the interspatial blocker is a gelling clay. 
   
   
       111 . The controlled release agricultural product of  claim 99 , wherein the fertilizer is secondary nutrients selected from the group consisting of sulfur, calcium and magnesium. 
   
   
       112 . The controlled release agricultural product of  claim 99 , wherein the fertilizer is micronutrients selected from the group consisting of boron, copper, iron, manganese, molybdenum and zinc. 
   
   
       113 . The controlled release agricultural product of  claim 99 , wherein the fertilizer is selected from the group consisting of nitrogen compounds, phosphorous compounds and potassium compounds. 
   
   
       114 . The controlled release agricultural product of  claim 113 , wherein the nitrogen compounds are selected from the group consisting of urea, ammonia, ammonium nitrate, ammonium sulfate, calcium nitrate, diammonium phosphate, monoammonium phosphate, potassium nitrate and sodium nitrate. 
   
   
       115 . The controlled release agricultural product of  claim 113 , wherein the phosphorous compounds are selected from the group consisting of diammonium phosphate, monoammonium phosphate, monopotassium phosphate, dipotassium phosphate, tetrapotassium pyrophosphate, and potassium metaphosphate. 
   
   
       116 . The controlled release agricultural product of  claim 113 , wherein the potassium compound is selected from the group consisting of potassium chloride, potassium nitrate, potassium sulfate, monopotassium phosphate, dipotassium phosphate, tetrapotassium pyrophosphate, and potassium metaphosphate. 
   
   
       117 . The controlled release agricultural product of  claim 113 , wherein the fertilizer contains nitrogen, phosphorous and potassium compounds in a ratio selected from the group consisting of 29-3-4, 16-4-8, 10-10-10, 15-5-10, 15-0-15, 22-3-14, 20-28-5 and 12-6-6. 
   
   
       118 - 184 . (canceled) 
   
   
       185 . A process for preparing a controlled release agricultural product comprising the following steps:
 mixing a control release holding substance selected from the group consisting of plant starches, protein gels, glues, gumming compositions, crystallizing compounds, gelling clays and synthetic gel forming compounds with an agriculturally beneficial material in aqueous solution selected from the group consisting of fertilizers, insecticides, herbicides and fungicides;   granulating the combination of agriculturally beneficial material and holding substance to solidify and harden the mixture, resulting in granules; and   drying the granules.   
   
   
       186 . The process of  claim 185  wherein the holding substance is a starch selected from the group consisting of corn starch, rice starch, potato starch, wheat starch, tapioca starch, starch containing D-glucopyranose polymers, amylose and amylopectin. starch acetates, starch esters, starch ethers, starch phosphates 
   
   
       187 . The process of  claim 185  wherein the holding substance is corn starch or wheat starch. 
   
   
       188 - 194 . (canceled) 
   
   
       195 . The process of  claim 185  wherein the holding substance is a gelling clay. 
   
   
       196 . The process of  claim 185  wherein the combination of agriculturally beneficial material and holding substance is heated while blending mixing. 
   
   
       197 . The process of  claim 185  wherein the granulated combination of agriculturally beneficial material and holding substance is screened to result in granules of a predetermined diameter. 
   
   
       198 . The process of  claim 185  wherein the combination of agriculturally beneficial material and holding substance is introduced into the granulator by spraying means. 
   
   
       199 . (canceled) 
   
   
       200 . The process of  claim 185  wherein the combination of agriculturally beneficial material and holding substance are solidified and hardened by a loss of heat and/or increase of concentration of the agriculturally beneficial material.