Film for dry pet food packaging
Kibble is a dry product that behaves like a moist one: it takes water from the air, its fats oxidise, and the aroma that makes it palatable leaves through the film. The pack is a barrier problem before it is a printing problem.
What the pack has to do
Four requirements, and only the first three have a number on the grade sheet. Odour is a design consequence of the barrier, not a value to quote.
| Requirement | What it protects | On the grade sheet |
|---|---|---|
| Moisture | Kibble that softens or dries out once the pack is open or in store | WVTR · 38 °C / 90 % RH |
| Oxygen | Fats and fat-soluble vitamins oxidising after filling | OTR · 23 °C / 0 % RH |
| Light | Fats and pigments fading under retail lighting | A design choice: clear AlOx or metallized |
| Seal strength | A heavy fill and a wide seal that has to hold on the bag line | Seal face · wetting tension |
Which grade to start from
A retail pouch is usually a PE structure and starts from metallized PE. A printed pack with a clear window starts from AlOx-coated BOPP, because the window has to stay transparent.
- PE structure VMNCPE barrier core
- 40–100 µm per order · OTR ≤ 1 · WVTR ≤ 1
- PE structure VMCPE sealant
- 40 µm standard 50–80 µm made to order
- PP structure ALOX BOPP-A
- 18 µm OTR ≤ 1, typ. 0.63 · WVTR ≤ 1, typ. 0.89
- High-barrier flat pack ALOX PET
- 12.0–12.5 µm OTR typ. 0.11–1.55
Retail pouch or bulk bag
A retail pouch is a thin structure on a high-speed line, so the sealant gauge and the seal window decide as much as the barrier. A bulk bag carries more weight and a wider seal; the same metallized PE route covers it at a heavier sealant gauge.
Both keep the structure inside one polymer stream, which is the reason metallized PE is the starting point rather than a laminate with a metalised PET layer.
When the pack needs a window
A clear window and a light barrier cannot both come from a metal layer. AlOx keeps the film transparent — it is an oxide layer, not a metal layer — so a window pack that also needs barrier starts from ALOX BOPP-A, and the window itself is part of the barrier.
What the trial has to prove
Seal strength at your fill weight, the seal window on your bag line, and the OTR of the finished pack rather than of the film alone. Send the finished-structure result back and it goes on the grade record.
Structures converters run
Starting points, quoted against the converting process you actually run. The trial decides the gauge and the seal window.
| Pack | Typical structure | Grade in the structure | What it buys |
|---|---|---|---|
| Retail pouch, PE | PE / VMNCPE / VMCPE | VMNCPE core · VMCPE seal | Oxygen and moisture barrier inside one polymer stream |
| Bulk bag, heavy fill | PE / VMCPE / PE | VMPE sealant, heavier gauge | Heat-sealable metallized web for a wide seal |
| Printed pack with a clear window | PP / AlOx-BOPP / PP | ALOX BOPP-A | Transparent barrier with the product visible |
| Flat-bottom high-barrier pack | PET / AlOx-PET / PE | ALOX PET | Transparent barrier where the process rules out BOPP |
Other application notes: coffee packaging · snacks and confectionery · clear-window packaging · documentation and samples.
Questions before the trial
If the answer you need is not here, ask it directly — technical questions get an engineer's reply, not a brochure.
Which grade for a dry pet food pouch?
Start from the structure. For a PE structure, VMNCPE as the barrier core with VMCPE as the sealant; for a PP structure with a window, ALOX BOPP-A at 18 µm. The trial confirms the gauge and the seal window on your line.
Is a clear film enough for light protection?
No: a clear oxide layer does not meter light the way a metal layer does. If the brief asks for maximum light barrier, the pack needs metallized PE, and that rules out a clear window in the same web.
Can the same film run on a bulk bag line?
The structure is the same route at a heavier sealant gauge. Seal strength at the fill weight and the seal window on the bag line are what the trial establishes.
What should I write in my own specification?
Write the condition with the number: OTR at 23 °C / 0 % RH to GB/T 19789 / ASTM D3985 and WVTR at 38 °C / 90 % RH to GB/T 26253 / ASTM E398. A barrier figure without its condition cannot be compared with another supplier's.
What is the minimum order?
One roll of ALOX film, one pallet of metallized PE. A4 sheets are free, and a sample roll ships with its dimension sheet and lot data.
Trial a pet food structure
Tell us the pack, the fill weight and the width. The sample roll ships with its lot data; the finished-structure result goes on the grade record when you send it back.
- Sales
- sales@recyclepac.com
- Phone
- +86 532 6776 6956
- Works
- Qingdao, Shandong, China