| 摘要 |
An improved insect-combatting device (e.g., for use against houseflies, gnats and mosquitoes) is disclosed. The device comprises a shaped solid body having a porous surface capable of gradually and continually releasing naled insecticide in an amount sufficient to provide an insecticidally active concentration of said naled over a prolonged period of time and comprises a synthetic resinous matrix material, from about 15 to about 35 weight percent of naled and a minor amount effective to retard spewing of the insecticide of finely divided silica particles and at least one C14 to C20 saturated aliphatic carboxylic acid or a salt or ester thereof. The device is formed from a mixture of the said synthetic resin, naled, finely divided si1ica particles, C14 to C20 to aliphatic saturated carboxylic acid or salt or ester thereof and a surface porosity control component that is non-reactive in the mixture and has a boiling point at or below the curing temperature to produce surface openings in communication with pores in said body by vaporization of said porosity control component to provide the release of naled gas at a rate effective to control insects in the vicinity of said body, but insufficient to form as spew on the body. |
