Pouch Film and Seal Sample Test Checklist

Pouch performance depends on more than the pouch outline. Film construction, thickness, sealant, product contamination, jaw temperature, dwell time, pressure, cooling and handling can interact. This checklist helps buyers prepare a representative film and seal trial before approving a premade-pouch or pouch-forming route. It is a test framework, not a guarantee of seal strength, shelf life or compatibility without the actual package and product.

1. Identify the pouch and intended process

Record the pouch type, finished width and length, opening, zipper or spout, gusset, notch, handle and intended orientation. State whether the pouch is supplied premade and open or formed from a roll. Identify the product, target fill, headspace and closure or seal required after dosing.

Assign a format ID and revision to every pouch drawing and artwork. Separate the launch pouch from future sizes. A trial on one size should not be reported as proof for all change parts or material revisions.

2. Freeze film and supplier information

Provide the film structure, nominal thickness, sealant, width, roll direction, core, winding direction, splice policy and supplier lot. If a pouch is already converted, record the film revision and converter information. State whether the material has a printed surface, coating, metallization or a special barrier requirement relevant to the project.

Record storage temperature, humidity and conditioning time where the supplier specifies them. Keep the material state visible: a lab sample, old stock and production-equivalent roll may behave differently. Do not replace a missing film specification with a generic “food-grade” or “high-barrier” label.

3. Mark the seal zones and keep-out areas

Draw the intended top, side and bottom seal widths and mark the area that must remain free of product, powder or liquid. Include zipper, spout, corner, notch, gusset and print-registration boundaries. For a premade pouch, identify the open mouth and the exact sealing surface. For a roll-fed route, show where forming and longitudinal or cross seals occur.

Note any seal that must carry a load, resist leakage or remain easy to open. The buyer’s approved test method should define acceptance. A visually closed seam is not automatically a leak-tight or mechanically acceptable seal.

4. Define product and contamination conditions

Describe viscosity, particles, dust, foam, oiliness, temperature and any tendency to smear into the seal area. For powders, record the fine fraction and dust-control method. For liquids or pastes, state whether the nozzle can stop cleanly and whether a drip may reach the seal. The test should include normal variation rather than only a clean empty pouch.

List allergen, color, fragrance, active-ingredient and cleaning concerns. Define how contaminated seals are detected, isolated and cleaned. The film trial should preserve the product identity and condition used; otherwise a clean-material result can be mistaken for production evidence.

5. Define the sealing test conditions

Record jaw or bar temperature, dwell time, pressure or force setting, cooling condition, line speed, pouch tension and machine recipe. State how settings are measured and what range will be explored. If the material supplier provides a recommended window, treat it as starting information to be confirmed with the actual equipment and product.

Run a planned matrix rather than changing several variables without a record. Note warm-seal handling, wrinkles, channel leaks, burn-through, delamination, jaw marks and incomplete closure. Keep rejected samples and identify the setting used for each one.

6. Test the package after sealing

Define the immediate checks: visual seal inspection, leak or pressure test, opening or peel observation, fill weight, pouch dimensions and closure presence. State sample quantity, timing after sealing and the measuring method. If cooling or conditioning is required before testing, record it.

Where shelf life, transport or drop performance matters, agree a separate validation plan with the buyer’s quality team. A short seal trial can screen settings; it cannot prove a long-term barrier, shelf life or every distribution condition.

7. Include handling and downstream checks

Observe pouch presentation, opening, filling, sealing, discharge, coding, inspection and accumulation. Record whether the pouch stands, lies flat, slides, sticks or turns during the route. Include a restart, replenishment and a difficult pouch revision if those conditions are important to the purchase.

For a premade-pouch machine, compare the scope with the VFFS versus premade-pouch guide. The sample-test protocol can control the run, while the FAT acceptance checklist can organize signed evidence.

8. Record results and open questions

For each sample, preserve pouch revision, film lot, product lot, machine settings, operator or technician assistance, accepted and rejected counts, defect reason and photos or measurements. Mark every conclusion as confirmed by test, supplier information, estimated or open. Do not publish a broad “compatible with all films” statement from one successful sample.

Send the film specification and seal-test plan to MUJIU before finalizing the packaging route. If the film, product or pouch geometry changes, reopen the affected review instead of carrying the old result forward automatically.

Minimum pouch test package

• Controlled pouch drawing, film structure, thickness and supplier lot.
• Product identity, fill target, temperature, particles and contamination risks.
• Seal zones, keep-out areas, closure details and acceptance method.
• Planned temperature, dwell, pressure, speed and cooling matrix.
• Leak, visual, dimensional and handling checks with sample quantity.
• Raw results, rejected samples, defect log and open-item register.