The sealant layer of a flexible lamination package is a critical component. Whether the application is Vertical Form / Fill / Seal VFFS, stand up pouch, plastic reclosable zipper packaging, or quad seal square cube packages, the sealant layer must:
1. be corona treated to the proper dyne level to accept either solvent or water based adhesives. The sealant layer is laminated to an outer layer usually of polyester (PET) or polypropylene (PP).
2. Heat seal through contaminants both liquid and dry in an often hostile environment. The sealant layer must prevent “channel leakers” when a foldover wrinkle occurs.
3. be clear for product visibility
4. have a low COF for machinability
5. be FDA and Kosher approved for prolonged and direct food contact in food grade packaging
Watch this video to learn about VFFS hot fill packaging.
Metallocene polyethylene resins provide better fast tack than EVA without the odor and taste transfer associated with EVA. Our most popular grade is 622 which combines the best properties of conventional polyethylene, metallocene and Linear Low Density LLDPE.
Providing barrier properties is not part of the sealant layer’s job description. If the sealant layer must provide a barrier, the most popular way is to use a coextruded EVOH core layer film. A barrier layer can be achieved by lamination to a Saran™–coated (PVDC) polyester or polypropylene.