this invention relates to a novel process and composition for treating the surface of an abs or other polymer sheet so that it will accept watercolor paints . more particularly , this invention involves using a series of adhesive ground compounds to modify the surface of the abs polymer or other sheet so that it becomes water absorbent to a certain degree . a method of treating the surface of a polymer so that it is acceptable for watercolor pigments comprising : roughening the surface of the polymer ; applying a layer of a mixture of soft gel gloss and kaolin clay to the roughened surface and allowing it to dry ; applying a second layer of soft gel gloss and kaolin clay mixture to the first layer of soft gel gloss and kaolin clay mixture and allowing it to dry ; and applying a layer of absorbent watercolor ground to the kaolin clay layer .