A Sticky Situation
Adhesion promoters
Because there are so many variations of ink and substrates, a variety of adhesion promoters can be implemented into the printing process. Rockow says that as an ink manufacturer, Collins Inkjet can add adhesion promoters directly into its ink.
“There are adhesion promoters that we put into the inks themselves,” she says. “That’s the magic of the chemistry. The chemists figure out what they need to put into the ink, especially when you’re dealing with the more difficult substrates.”
In addition to adhesion promoters that can be put into the ink, there are others that can be added to the substrate.
Edwards explains that these adhesion promoters can serve a variety of purposes. In some instances, the promoter can be used to change the surface energy, or it could change the chemical polarity of the printing surface. But before implementing an adhesion promoter, Edwards recommends testing it first.
With so many potential ink and substrate combinations, selecting the correct adhesion promoter is essential. “The fact that there are so many of them tells you they aren’t all the same and that they don’t all work the same way on different substrates,” says Edwards.
Don’t hesitate to talk with your ink and substrate vendors to find which are best for each application.
Cory Francer is an analyst at NAPCO Research. He formerly served as editor-in-chief of Packaging Impressions.