Patent ID: 6432476
Filing Date: 2002-08-13
Classification: A01N

Abstract:
A process for preparing an emitter for controlled and durable release of a semiochemical substance from a support having a network of micropores, mesopores and macropores, the support being selected from the group consisting of zeolites and of inorganic molecular sieves selected from aluminosilicates and aluminophosphates, whereinthe process comprises adapting physiochemical properties of the support to characteristics of the semiochemical substance and to specific needs of release kinetics, whereby said properties are adapted to said semiochemical substance and to said specific needs of release kinetics by modifying at least one property selected from the group consisting of Si/Al ratio, acidity, compensation cations, pore size, compression degree and surface/weight ratio of the support, whereby, for reducing the release rate, the support is subjected to at least one treatment selected from the group consisting of increasing the number and strength of the adsorption centers of the support by increasing the Si/Al ratio of the support, and impregnating the support with the semiochemical substance; providing Bronsted acidity to the support by introducing protons into the support and impregnating the support with a semiochemical substance having functional groups being capable of forming hydrogen bonds with the support; reducing cation charge/radius ratio of a support having compensation cations and impregnating the support with polar semiochemical substance; reducing pore sizes of the support, and impregnating the support with a semiochemical substance having a size being smaller than at least a portion of the sizes of the pores of the support; impregnating the support with the semiochemical substance and subjecting the impregnated support to compactation by applying pressure; and impregnating the support with the semiochemical substance and reducing the surface/weight ratio of the substance support by compactation.