Preview · about 1 minute
Plant-floor overview. Unlock below for the full converter checklist.
Extrusion coating and laminating put a molten thermoplastic (usually PE or a copolymer) on paper, foil, or film. The finished pack is only as good as that bond. High melt index PE can flow into paper fibers (mechanical lock). On smooth PET or foil you need oxidation, flame, corona, ozone, and/or a chemical primer. Oxidation that is too hard raises odor and heat-seal temperature. Primers are how you get bond without cooking the melt.
A primer has to wet a clean face and then join substrate to extrudate (covalent, hydrogen bond, van der Waals, or a mix). Dirt, foil rolling oil, slip, wax, and low-molecular-weight polymer are weak boundary layers. Apply by gravure, smooth roll with or without a metering bar, or air knife. The primer must survive later heat seal, hot fill, thermoform, or freeze.
What's in this guide
- Primer families
- Where they fit
Longer plant training (5–10 min)
Coming soon — downloadable deep-dive for the floor.
General plant guidance only — not a substitute for your process, SDS/TDS, or line trials. Call 800-249-0337 to match a grade.