A nylon-polystyrene microcapsule sensitive to an outside stimulus such as an electric field was prepared by a combined process of interfacial polymerization and solvent evaporation. A ferroelectric liquid crystal monomer containing carboxyl-p-benzoyloxybenzoate (the mesogenic core) and carboxyl-(s)-(-)-2-methylbutylester (the terminal group) was much effective as a functional component which responds to an electrical field. The monomer extremely has a sensitive response to the outside stimulus, because it has spontaneous polarization. The microcapsule immobilized ferroelectric liquid crystal could controll the permeability of L-tryptophan, which is used as an encapsulated core material, compared to that of the microcapsule with no monomer under the external intermittent electrical field.