When purchasing sealing film, price is often the first factor considered. But if a batch fails due to quality issues and has to be scrapped, the small amount saved might not even cover a single customer complaint. Besides price, there are several other aspects more worth your time.

Quality control capability

This is the most critical factor. The core function of sealing film is sealing, and sealing effectiveness depends on parameters such as heat-seal layer thickness, aluminum foil pinhole density, and peel strength. Thickness tolerance should be controlled within ±3μm, pinhole density ≤1/m², and peel force ≥5N/15mm. These figures don't rely on supplier promises — you should review consecutive batch Certificate of Analysis (CoA) reports, paying close attention to consistency in heat-seal layer thickness and pinhole data.

Equipment configuration determines the level of process control. Check whether the manufacturer has in-line thickness measurement and pinhole scanning equipment — these are the foundation for stable production. Many manufacturers can produce low-cost film, but few can keep every batch consistent.

Certifications and compliance

If the sealing film is used for food or pharmaceutical packaging, the supplier's qualifications directly determine whether your product can be legally marketed. ISO9001 is the baseline; food-grade also requires FDA or GB certification, while export products need to meet EU or RoHS requirements. If the supplier can't provide the corresponding certification documents, it's advisable to exclude them.

Supply stability

Production lines can't wait for film. Evaluate the supplier's production capacity, equipment utilization, and scheduling capability to confirm they can maintain stable supply during peak order periods. Suppliers with an on-time delivery rate above 95% are more trustworthy; if it's below 60%, it generally indicates an unstable supply chain. In addition, whether the supplier supports small-batch customization or rapid sampling is also crucial for new product testing or urgent replenishment.

Technical support and after-sales service

Sealing film selection isn't just a one-time purchase — it also involves compatibility with your production line. Whether the supplier can provide selection recommendations based on your bottle mouth material and product characteristics, and whether they can respond quickly when problems arise, matters more than price in the long run. Response time for after-sales issues, return/exchange policies, and whether on-site debugging services are available should all be clarified before cooperation begins.

If you still have questions about supplier screening, Leadtra Packaging can assist in evaluating samples and test reports to help determine whether quality meets standards. Choosing a supplier isn't about picking the cheapest — it's about picking the most suitable.