Method of preparing a water-soluble stable arthropodicidally-active foam matrix

A method for making a foamable arthropodicidally-active composition-of-matter that is characterized as a formulation, said method comprising the steps of:

• introducing, into a C.sub.1 to C.sub.4 lower alkanol solvent, an arthropodicidally-active toxicant ingredient and an emulsifier ingredient, both of which ingredients are soluble in the lower alkanol solvent, and heating the ingredient-containing lower alkanol solvent to a predetermined elevated temperature and for a period of time sufficient to dissolve the ingredients contained therein, thereby producing an ingredient-containing lower alkanol solution;
• introducing into water an arthropodicidally-active water-soluble toxicant, and heating the water to a predetermined elevated temperature and for a period of time sufficient to dissolve the water-soluble toxicant contained therein, thereby producing an aqueous ingredient-containing solution;
• and
• combining respective effective amounts of the ingredient-containing lower alkanol solution and the aqueous ingredient-containing solution, to produce an aqueous lower alkanol solvent consisting essentially of water and about 3 parts-by-weight to about 40 parts-by-weight of the C.sub.1 to C.sub.4 lower alkanol, based upon 100 parts-by-weight of total water and lower alkanol, wherein the amount of emulsifier that is present in the formulation is effective for enabling the formulation to form a foam matrix that is able to remain stable for at least about 5 days, the toxicant being present in an amount of about 0.01 parts-by-weight to about 2.5 parts-by-weight, based upon 100 parts-by-weight of the arthropodicidally-active composition-of-matter, the emulsifier being present in an amount of at least about 1 weight percent based upon total weight of the arthropodicidally-active composition-of-matter, wherein the formulation is characterized as a water-out emulsion prior to formation of the foam matrix.