WATER-BASED ADHESION PROMOTER FOR POLYPROPYLENE AND COATING OF POLYPROPYLENE MATERIAL USING THE SAME

摘要

PROBLEM TO BE SOLVED: To obtain a water-based adhesion promoter for enhancing the coating material adhesion to a polypropylene material in place of a primer coating, and to provide a method for coating the polypropylene material using the promoter. SOLUTION: This water-based adhesion promoter comprises a modified chlorinated polypropylene containing a chlorinated polypropylene moiety and a maleic anhydride moiety bonded to the chlorinated polypropylene moiety and having 15-25 wt.% of chlorine content and 1-5 wt.% of the maleic anhydride moiety content, an amine-neutralized water-soluble resin, a wetting improving agent and water. The compounding ratio of the modified chlorinated polypropylene is 25-90 wt.% based on the sum total of the modified chlorinated polypropylene and the amine-neutralized water-soluble resin and the compounding ratio of the wetting improving agent is 2.5-6.0 wt.% based on the whole water-based adhesion promoter. The solid content is 2-10 wt.% based on the whole water-based adhesion promoter. The method for coating the polypropylene material comprises a pretreating step for prewashing the polypropylene material, coating the prewashed polypropylene material with the water-based adhesion promoter and drying the coated water-based adhesion promoter and a coating step for coating the material after the pretreating step with a finish coating material.