PURPOSE: To provide a new and improved encapsulating compsn. rapidly and effectively obtainable and excluding the necessity for separating an encapsulating substance from a continuous phase liquid.

CONSTITUTION: The compsn. is produced by a method wherein an aq. phase containing an emulsifier selected from a group consisting of sodium, potassium, magnesium, calcium and ammonium lignin sulfonates in specific concn. is prepared (a) and a water immisible phase substantially composed of a specific concn. of polymethylene polyphenylisocyanate dissolved in a water immiscible substance with specific concn. of a specific substance is dispersed in the above mentioned aq. phase to form a dispersion of water immiscible phase small droplets over the whole of the aq. phase (b) and polyfunctional amine is added to the dispersion in specific concn. under stirring to react the above mentioned amine with polymethylene polyphenylisocyanate (C) to form a shell wall of polyurea around the above mentioned water immiscible substance.