A rodent bait suitable for use on crops comprising a unitary body of intimately mixed particles of metal phosphide such as zinc phosphide, citric acid and a hard wax component. The hard wax component forms a protective coating around the particles of metal phosphide and citric acid. The citric acid has been found to completely decompose the metal phosphide toxicant upon absorption of moisture by the unitary body. Thus, the rodent bait of the invention has the advantage of preventing decomposition of the metal phosphide toxicant until a preset time when it completely decomposes the metal phosphide leaving no toxic residues.
A pest control product is provided from a metal phosphide particle coated with a water soluble coating that has been rendered water repellent. The coating also contains a material which will chemically or physically disintegrate to cause apertures in the coating to provide access for water to the phosphide particles.
The invention provides a pesticide containing an aluminium or magnesium phosphide and an ignition inhibiting agent essentially consisting of at least one aromatic hydrocarbon which suppresses the tendency of phosphin evolved under the influence of e.g. atmospheric moisture, to self-ignite.
An environmentally-safe, broad spectrum insecticide that is toxic to invertebrate animals and non-toxic to vertebrate animals. The insecticide comprises a water solution of hydroxy acyclic acid, such as citric acid, and ionic or non-ionic surfactant thoroughly mixed together. The insecticide may be applied by aerosol, misting, spraying, or pouring on the insects or into their abodes. The composition is also an effective mosquito repellant when applied to human skin.
A pesticide composition comprising a particulate hydrolyzable metal phosphide is rendered liquid phase water repellent by treating particles of the composition with a silicon-organic compound. The silicon-organic compound has at least one reactive moiety, preferably hydrogen capable of reacting with and binding to reactive sites contained on surfaces of particles of the composition. Preferably, the reactive group is hydrogen are the reactive site is a hydroxy group. The silicon-organic compound can also undergo cross-linking reactions. In the water-repellent treatment the silicon-organic compound may be applied to and be reacted to become bonded to any of the solid ingredients of the composition, including urea which serves as a self-ignition inhibitor. Preferably at least part of the silicon-organic compound is bonded to particles of the metal phosphide. Advantages result if all the silicon-organic compound is thus bound to the metal phosphide. On the phosphide surfaces novel metal-silicone compounds may form. The treatment protects the phosphide against access of liquid state water and resulting violent reaction, without inhibiting the access of water in its gaseous state (e.g. atmospheric moisture) required for the generation of phosphine when the composition is used as a fumigant. The hydrophobing reaction of the silicon-organic compound, e.g. polymethyl hydrogen siloxane is promoted by heat or catalysts (metal organic compounds, bases, e.g. ammonia, ammonium compounds, amines). The composition in powder form (enclosed in gas permeable sachets) or in tables may contain additives, e.g. self-ignition inhibitors such as ammonium carbamate, amonium carbonate and urea.
A pesticide composition comprising a particulate hydrolyzable metal phosphide is rendered liquid phase water repellent by treating particles of the composition with a silicon-organic compound. The silicon-organic compound has at least one reactive moiety, preferably hydrogen capable of reacting with and binding to reactive sites contained on surfaces of particles of the composition. Preferably, the reactive group is hydrogen and the reactive site is a hydroxy group. The silicon-organic compound can also undergo cross-linking reactions. In the water-repellent treatment the silicon-organic compound may be applied to and be reacted to become bonded to any of the solid ingredients of the composition, including urea which serves as a self-ignition inhibitor. Preferably at least part of the silicon-organic compound is bonded to particles of the metal phosphide. Advantages result if all the silicon-organic compound is thus bound to the metal phosphide. On the phosphide surfaces novel metal-silicone compounds may form. The treatment protects the phoshide against access of liquid state water and resulting violent reaction, without inhibiting the access of water in its gaseous state (e.g. atmospheric moisture) required for the generation of phosphine when the composition is used as a fumigant. The hydrophobing reaction of the silicon-organic compound, e.g. polymethyl hydrogen siloxane is promoted by heat or catalysts (metal organic compounds, bases, e.g. ammonia, ammonium compounds, amines). The composition in powder form (enclosed in gas permeable sachets) or in tablets may contain additives, e.g. self-ignition inhibitors such as ammonium carbamate, ammonium carbonate and urea.
