Atmospheric Plasma Processing of Film Substrates for Enhanced Adhesion of EB Curable of Printing Inks and Clear Coatings

Atmospheric Plasma Processing (APP) under controlled gaseous atmospheres of film substrates leads to grafting of nitrogen based chemical functions onto the surface of the substrates. APP treated film surfaces of polyolefins such as BOPP show excellent adhesion with acrylate based EB printing inks and clear coatings eliminating the need to use print receptive primer coatings. Adhesion level depends on the percentage of grafted nitrogen and nature of nitrogen function as evidenced by XPS surface analysis following APP. Results are presented showing excellent adhesion of EB cured offset ink and clear coatings on plain BOPP following APP treatment. The use of APP treatment together with EB cured inks and clear coatings provide an attractive alternative to solvent based ink and coatings for flexible packaging applications.