Custom Mylar Bags and Aluminium Foil Pouches

What "mylar" actually means

Mylar® is a registered trademark of DuPont Teijin Films for biaxially oriented polyester film — BoPET. In the packaging trade the word has drifted: when people ask for mylar bags they almost always mean a silver, opaque, high-barrier pouch, and that pouch is either an aluminium-foil laminate or a metallised polyester laminate. Neither one is branded Mylar® film, and any supplier who tells you the two words are interchangeable is selling you on vocabulary rather than on structure.

We make both and we label them plainly. PET/ALU/PE carries a real aluminium foil layer. METPET/PE carries a vacuum-deposited metal coating a fraction of the thickness. They look similar on a shelf and behave very differently over twelve months.

Foil or metallised: how to choose

• Aluminium foil (PET/ALU/PE) — opaque to light, effectively a total oxygen and moisture barrier, the standard for roasted coffee, powders and anything with a long claimed shelf life
• Metallised polyester (METPET/PE) — high barrier at a lower price and a brighter metallic look, suited to short-cycle products that sell through in weeks, not years
• Matte PET/ALU/PE — the same foil barrier with a soft-touch matte surface that photographs well
• Kraft/ALU/PE — foil barrier behind a paper outer, for brands that want the natural look without giving up protection
• If a product is light-sensitive, choose foil: metallisation reduces light transmission but does not eliminate it

Stock foil sizes and structures

Every foil laminate we hold unprinted in our own warehouse is listed below — stand-up pouches, side-gusset bags with a valve and flat bottom bags with and without a zipper. The table is generated from the live stock catalogue, so it cannot show a size we do not actually keep.

Filling, sealing and oxygen absorbers

The inner layer is polyethylene, so the pouches close on ordinary heat-seal equipment: an impulse sealer for small batches, standard jaw sealers on a filling line. Foil laminates seal cleanly as long as the seal area is kept free of product dust — powders in the seal are the usual cause of a leaking pouch, not the material.

Foil pouches are commonly used together with oxygen absorber sachets for long-term dry food storage. We do not supply absorbers, and the pouch does not need them for normal retail shelf life; if you plan to use them, tell us the fill weight and we will size the pouch with the headspace to fit.

Printing on foil laminates

Foil reflects, so artwork printed straight onto it takes on a metallic cast. Where the design needs flat, exact colour we print a white base under it and keep bare metal only where you want the silver to show — a deliberate effect rather than an accident. Rotogravure printing takes up to 10 colours, and we send a digital proof within 24–48 hours of receiving print-ready files.

Matte lacquer, spot gloss and soft-touch finishes are all available on foil structures. Production runs 15–25 business days after artwork approval; physical samples of our stock pouches ship in 2–3 days if you want to feel the material first.

What brands pack in foil pouches

• Roasted coffee and espresso blends, with a one-way degassing valve
• Protein powder, pre-workout and powdered supplements
• Freeze-dried meals and long-shelf-life dry food
• Spices, herbs and seasoning blends that lose aroma in clear film
• Pet food and treats with a high fat content
• Powdered drinks, milk powder and instant mixes

Frequently asked questions