GB401705A - Improvements in or relating to preparations for agricultural or horticultural pest control, and the manufacture thereof - Google Patents

Abstract

Materials for repelling, controlling, preventing, or destroying insects, fungi, bacteria, or other pests are produced by dispersing a fused insecticidal or like active solid in and/or upon dry, light, finely-divided, absorbent, precipitated silica, and solidifying. The silica may be prepared as described in Specifications 294,681, 299,483, [both in Class 1 (ii), Inorganic compounds, other than &c.], or 357,993, [Group III]. Active solids referred to are naphthalene, p-dichlorbenzene, and sulphur. An intimate mixture of the active ingredient with the silica is heated, while stirring, to a temperature above the melting point of the former, the product then being cooled under continued stirring. During or after the preparation, other solid or liquid active substance, such as finely divided copper compounds, may be incorporated. The products may have a particle size of under 1 micron and are suitable for dusting or dry spraying. According to the Provisional Specification, the carrier may be any finely-divided, preferably absorbent, solid, for example diatomaceous earth or precipitated calcium carbonate. Additional substances which may be incorporated include finely divided or colloidal sulphur, and copper.