Stabilized chemical composition

Abstract

Stabilized liquid agrochemical compositions are provided that comprise flowable, aqueous dispersion concentrates comprising a) a continuous aqueous liquid phase; b) at least one dispersed, solid phase comprising a dispersion of polymer particles having a mean particle size of at least one micron, wherein the outside surfaces of the particles comprise a colloidal solid material and wherein the particles have at least one agrochemically active ingredient distributed therein, optionally a non-porous particulate mineral that acts as a diffusion barrier to slow the release of the active ingredient, and optionally at least one non-cross-linkable mobile chemical such that the extraction of this chemical from the disperse phase renders it porous in a manner that allows the active ingredient to diffuse out. The colloidal solid is used to stabilize the polymerizable resin in an emulsion state during preparation. In one embodiment, the agrochemically active ingredient is a solid and is distributed within the dispersed solid phase or is a liquid and is distributed within the dispersed solid phase. The compositions of the invention can be used directly or with dilution to combat pests or as plant growth regulators.

We claim: 
     
         1 . A process, comprising:
 effecting cure, solidification, or polymerization of a dispersed phase of an emulsion to produce a dispersion of polymer matrix particles,   wherein said dispersed phase comprises:
 a liquid curable, solidifiable, or polymerizable resin, 
 at least one agrochemically active ingredient, and 
 a colloidal solid emulsion stabilizer distributed at the surface of the polymer matrix particles. 
   
     
     
         2 . The process according to  claim 1 , wherein the polymerizable resin is selected from epoxy, polyisocyanate, polyamine, aminoplast, phenolic and polyester. 
     
     
         3 . The process according to  claim 2 , wherein the polymerizable resin is a thermosetting epoxy resin. 
     
     
         4 . The process according to  claim 3 , wherein the epoxy resin comprises a diglycidyl ether of bisphenol A, glycerol, polypropyleneoxide or resorcinol, or a mixture of two or more of these ethers. 
     
     
         5 . The process according to  claim 3 , wherein curing of the epoxy resin is accomplished using an amine hardener. 
     
     
         6 . The process according to  claim 4 , wherein curing is accomplished by using an amine hardener comprising a poly(oxypropylene)diamine. 
     
     
         7 . The process according to  claim 6 , wherein the colloidal solid emulsion stabilizer is selected from carbon black, metal oxides, metal hydroxides, metal carbonates, metal sulfates, polymers, silica and clays. 
     
     
         8 . The process according to  claim 7 , wherein the colloidal solid emulsion stabilizer is an agrochemically active ingredient in finely divided form. 
     
     
         9 . A process for making an aqueous liquid dispersion concentrate incorporating at least one agrochemically active ingredient comprising the steps of:
 a. dissolving or suspending at least one agrochemically active ingredient in a solution of a thermoplastic polymer in a volatile solvent optionally containing a non-porous particulate mineral and optionally containing a non-cross-linkable mobile chemical;   b. combining said solution or suspension with an aqueous liquid containing a colloidal solid emulsion stabilizer and applying mechanical agitation sufficient to form an emulsion of said solution or suspension; and   c. applying heat to evaporate the volatile solvent to produce an aqueous liquid dispersion of polymer particles which contain at least one agrochemically active ingredient and a colloidal solid distributed at the surface of the polymer particles.   
     
     
         10 . A process for making an aqueous liquid dispersion concentrate incorporating at least one agrochemically active ingredient comprising the steps of:
 a. dissolving or suspending at least one agrochemically active ingredient in a melt of a thermoplastic polymer optionally containing a non-porous particulate mineral and optionally containing a non-cross-linkable mobile chemical;   b. combining said solution or suspension with an aqueous liquid containing a colloidal solid emulsion stabilizer and applying mechanical agitation sufficient to form an emulsion of said solution or suspension; and   c. cooling the emulsion to solidify the disperse phase and thereby produce an aqueous liquid dispersion of polymer particles that contain at least one agrochemically active ingredient and a colloidal solid distributed at the surface of the polymer particles.   
     
     
         11 . The process according to  claim 10 , where the colloidal solid emulsion stabilizer is selected from carbon black, metal oxides, metal hydroxides, metal carbonates, metal sulfates, polymers, silica and clays. 
     
     
         12 . The process according to  claim 10 , where the colloidal solid emulsion stabilizer is an agrochemically active ingredient in finely divided form. 
     
     
         13 . The process according to  claim 1 , wherein the continuous phase is water and the colloidal solid is a hydrophilic fumed silica. 
     
     
         14 . The process according to  claim 1 , wherein the continuous phase comprises water and a substantially water-miscible, non-aqueous liquid, and the colloidal solid is a hydrophilic fumed silica. 
     
     
         15 . The process according to  claim 1 , wherein the continuous phase is a solution of xanthan polysaccharide in water and the colloidal solid is kaolin clay.