PURPOSE: To effectively thicken an emulsion to a emulsion excellent in viscosity characteristics such as thixotropy and leaving stability and useful for various kinds of uses by adding a specific acetoacetic acid ester group-containing polyvinyl alcohol-based resin thereto.

CONSTITUTION: (A) An acetoacetic acid ester group-containing polyvinyl alcohol containing (A1) ≤2wt.%, especially ≤0.5wt.% acetic acid salt of an alkali metal and (A2) ≤5wt.%, especially ≤2wt.% acetic acid and having 0.01-100, especially 0.01-10 weight ratio of A1/A2 is added to (B) an emulsion having 30-60wt.% concentration of a resin content (B1), preferably in an amount of the component A of 0.02-50 pts.wt. based on 100 pts.wt. of the component B1.