DuPont™ Sclairfilm® LX-1 LLDPE film at 38.1 µm nominal thickness is specified as a laminating web for multi-layer flexible structures. The five downstream positions below cover the web as a sealant, barrier, or protective ply. Each position identifies the regulatory standard, construction ratio, production route, and finished article categories without extrapolating beyond established LLDPE laminating practice.

What Limits Seal Integrity in Low-Temperature Snack Packaging Laminates Using 38.1 µm LLDPE?

For dry-food and snack rollstock, the 38.1 µm Sclairfilm® LX-1 web is positioned as the inner sealant layer in a reverse-printed laminate. The industry compliance standard is FDA 21 CFR 177.1520(c) for olefin polymers in food-contact use, with EU Regulation (EU) No 10/2011 overall migration below 10 mg/dm²; converters typically test the finished laminate under EN 1186 migration protocols for dry snack simulants. The lamination ratio places the 38.1 µm LLDPE web at 60–73% of total caliper in a typical 12 µm PET / 2.0–2.5 g/m² adhesive / 38.1 µm LLDPE stack, depending on print primer weight. The downstream process is adhesive lamination on a solventless or solvent-based laminator, with corona treatment of the film to a surface tension of 38–42 mN/m, nip temperature 45–60°C, line speed 120–180 m/min, and a 24–48 h ambient cure at 25–35°C before slitting. Pouch making uses heat seal jaws at 115–150°C, dwell 0.3–0.6 s, and pressure 2–4 bar. The low seal-initiation temperature of the LLDPE layer reduces thermal load on the outer printed BOPP or PET web. Terminal finished product types include pillow pouches, gusseted snack packs, and cold-seal release register side-gusset formats. This structure is not intended for high-acid liquid hot-fill above 90°C; for those conditions the laminate must be re-qualified for seal creep and delamination resistance.

Liquid Agricultural Chemical Pouch Constructions with Foil / LLDPE Sealant Layers

For liquid agricultural chemical single-dose sachets, the 38.1 µm Sclairfilm® LX-1 web is used as the innermost heat-seal layer in a foil-containing laminate that must resist the packaged liquid and prevent pinhole corrosion. The applicable compliance framework includes 49 CFR 173.154 for non-bulk packagings of hazardous materials and the UN Model Regulations packaging instructions for limited quantities, plus chemical compatibility testing per ASTM D543-21. The lamination ratio is commonly 12 µm PET / 9 µm aluminum foil / 38.1 µm LLDPE, and the 38.1 µm web represents 60–65% of total laminate thickness by caliper, with adhesive layers at 2.5–3.5 g/m² on each side of the foil. The downstream production process involves a two-pass adhesive lamination line: the foil is first bonded to the PET at 2.5–3.0 g/m², then the LLDPE sealant web is bonded to the foil at 2.5–3.5 g/m², followed by 48–72 h cure at 30–40°C. Sachet forming on vertical or horizontal form-fill-seal machines uses seal jaw temperatures of 130–160°C, dwell 0.5–1.0 s, and pressures of 3–5 bar. Terminal finished product types include single-dose liquid herbicide sachets, liquid fertilizer pouches, and chemical reagent portion packs. When the packaged liquid contains more than 30% aromatic hydrocarbon, published data for this specific film configuration is limited, and qualification must include long-term sachet storage at 40°C and 75% relative humidity with periodic seal strength evaluation.

When 38.1 µm LLDPE Is Substituted for Conventional LDPE in Laminated Woven Polypropylene Sacks

For dry bulk and chemical packaging, the 38.1 µm Sclairfilm® LX-1 web is adhesive-laminated to woven polypropylene fabric to provide a moisture barrier and sealable inner surface. The industry compliance standard for non-dangerous goods FIBC and sack construction is ISO 21898:2004; for regulated materials, additional 49 CFR 173.24 packaging compatibility and ASTM D543-21 chemical exposure data are used during qualification. The lamination ratio is defined by the woven PP fabric mass of 65–85 g/m² and the film mass of approximately 35 g/m², meaning the 38.1 µm LLDPE layer contributes 29–35% of the total laminate mass, while providing the complete impermeable inner ply. The downstream production process applies a polyurethane adhesive at 2.5–4.0 g/m² to the woven PP, nips the corona-treated LLDPE web at 60–80°C roll temperature and 3–5 bar pressure, then cures the roll for 24–48 h at 30–35°C. Sack conversion uses bottom gusset formation, seam sewing, and heat-sealed valve strips. Terminal finished product types include laminated woven sacks for minerals, dry chemicals, animal feed, and seed packaging, as well as FIBC liner tubes. If the woven PP fabric has surface contamination or corona treatment below 38 mN/m, adhesive transfer to the LLDPE web becomes uneven and seam leakage may occur in hygroscopic powder applications.