Membrane containing a liquid active substance and process for the production of same

摘要

A liquid active substance-containing membrane having an anisotropic structure comprising (a) a polymeric cellular layer containing a myriad of minute closed cells and septa thereof and (b) a dense thin layer covering the surface of the cellular layer, wherein the minute cells contain therein a liquid active substance having a limited solubility in the polymer at normal temperature. The membrane of the present invention can be advantageously used to release a liquid active substance such as pheromones and pesticides at a substantially constant, controlled rate over a long period of time.