A SUSTAINEDLY VAPOR-RELEASING BODY FOR ENVIRONMENTAL CONTROL
摘要
The invention provides a sustained vapor-releasing body for emission of a gasifiable and diffusible substance capable of exhibiting an activity even in an extremely low concentration in the atmospheric air such as sex pheromones for insects and insecticides used for the pest control in agriculture and forestry, bactericides, perfumes and the like at a controlled rate of emission. The vapor-releasing body of the invention comprises a solid base particle shaped of a blend of an inert carrier material such as anhydrous silicic acid and the gasifiable active substance together with a binder and a coating layer on the surface of the solid base particle formed of a film-forming polymeric material such as a cellulose derivative including cellulose ethers, cellulose esters and cellulose ether esters. Incorporation of an inorganic powdery material into the coating layer further provides a means for controlling the rate of vapor emission from the body and easiness in the preparation thereof.