PURPOSE: To produce the objective compsn. which is a water-base dispersion, is highly stable, and has improved water repellency and waterproofness.

CONSTITUTION: This compsn. is produced by mixing a compsn. comprising 0.1-30wt.% colloidal silica particles, 0.001-1wt.% cationic surfactant, 0.1-10wt.% low-viscosity oil, 0.01-1wt.% silicone surfactant, and 58-99wt.% water, with a silica colloid dispersed in water, a cationic surfactant, and a silylating agent to give the first emulsion soln., dehydrating the first emulsion soln. by azeotropic distillation to give a silica sol dispersed in a nonpolar org. solvent, adding a low-viscosity oil, a silicone surfactant, and water to the resulting silica sol to give the second emulsion soln., and distilling out the nonpolar solvent from the second emulsion soln.