Static control and web cleaning are critical to high-quality package printing.

By Tom Polischuk

For web-cleaning systems, part of the challenge is knowing what levels of contamination removal are needed. For pre-coating, Zuments recommends removal of particles greater than five microns for films and 40 microns for paper labels. In printing applications, he says flexible packaging should be at levels greater than 25 microns and paper labels at 40 microns. He emphasizes two key points: these targets are simply guides and not the “final word” and also that “no cleaning system can remove 100 percent of all particles of all sizes.”