PURPOSE: To obtain a high-viscosity emulsion having appropriate structural viscosisy by adding an aliphatic dialdehyde to a high molecular emulsion containing a water-soluble polymer having hydroxyl group.
CONSTITUTION: To 100pts.wt. of a water-soluble polymer within a high molecular emulsion containing a water-soluble polymer having hydroxyl group, 0.5W50pts.wt. of an aliphatic dialdehyde is added and mixed. As an aliphatic dialdehyde to be used, glyoxal, malonaldehyde, succinaldehyde or the like are preferred. As a high molecular emulsion to be used, is prefferred an ethylenevinyl acetate resin emulsion (containing 8W50wt% by of ethylene) useful as an adhesive agent for polyvinyl chloride overlay, mortar depositing agent, mortar mixing agent or the like.