Thirty years of getting one thing right: the seal
Shanghai Ziling Packaging has been making closure liners since 1996. We are a manufacturer, not a trading office — compounding, coating, die-cutting, cleanroom assembly and laboratory inspection all happen under our own roof in Lingang, Shanghai.
A liner is a small part with a large job
A closure liner sits between your product and the outside world. It is the difference between a pack that arrives intact and one that leaks in a container, oxidises on a shelf, or gets rejected on the filling line.
Because every container, cap and fill is different, we do not sell liners from a shelf. We match the structure — the layers, the heat-seal material, the thickness, the diameter — to your bottle mouth and your process, then prove it with samples on your own line.
What we keep under our own roof
Every step that can affect how your liner performs is controlled here — which is why we can hold a seal spec stable across repeat orders.
Compounding & coating
Heat-seal lacquers, wax and adhesive layers formulated in-house, so the layer that bonds to your container is matched to its plastic rather than approximated.
Die-cutting & tooling
Any diameter from 9 to 182 mm, any outline — round, ring, tab, multi-hole. New tooling is made in-house, which is why a first sample can reach you quickly.
Cleanroom assembly
Class-100,000 cleanroom assembly and GMP-aligned practice, originally built around pharmaceutical packaging requirements.
Laboratory inspection
A 150 m² physics and microbiology laboratory for raw-material checks, seal-strength testing and finished-goods inspection before dispatch.
Structure engineering
More than 100 liner structures developed to date. When a new fill or container does not fit an existing build, we engineer a new layer stack.
Export & logistics
Shipment from the Port of Shanghai, about 40 km from the plant, to customers across Asia, the Americas, Oceania, the Middle East and Africa.
Batch-to-batch consistency is the product
Most sealing problems are not design problems — they are variation problems. These four practices are how we keep the hundredth carton identical to the first sample.
Locked formulations
Once a structure passes first-article inspection on your line, the formulation and layer order are frozen for the life of the project.
Raw-material traceability
Incoming foil, film, paper and adhesives are checked and recorded, so a lot can be traced back through production to its raw material.
Inspection before dispatch
Seal strength, dimensions and appearance are inspected on the finished goods — not just at the start of the run.
Stable supply
Typical lead time of seven days after order confirmation, with raw materials in stock and in-house tooling to absorb demand peaks.
What we can build to your drawing
Almost nothing about a Ziling liner is fixed except the standard we hold it to.
| Diameter | 9–182 mm, or per your drawing |
|---|---|
| Thickness | 0.2–1.7 mm total for foil liners; up to 3–4 mm for foam liners |
| Layer build-up | One-piece, two-piece, separate-type, high-barrier, hot-melt |
| Heat-seal material | Matched to PE, PET, PP, PS, PVC, COEX or glass |
| Outline | Round, ring, tab, pull-tab, perforated, multi-hole, any die-cut shape |
| Branding | Surface printing, opening instructions, steel-stamp embossing |
| Packaging | Food-grade PE bags and cartons; storage −20 °C to +50 °C |
Come to us with a container, leave with a matched structure.
Tell us what you fill and what it goes into. Our engineers will propose a build-up, send a datasheet and make sample liners in your diameter.