Materials & compliance
How are blister packs made, and how thick is blister film?
Short answer
A blister machine heats a plastic film (usually PVC or PET) and forms it into cavities, the product is dropped in, and a lidding foil or printed card is heat-sealed on top; the strip is then cut and printed with batch and expiry details. Pharma PVC blister film is commonly around 250 microns; AVI's AVI Blis film runs from 150 to 800 microns, with a PVDC-coated barrier option.
Part of the guide: PVC, blister and specialty films guide
- AVI Blis thickness150–800 microns
- Common pharma PVCabout 250 microns
AVI products for this
- AVI Blis PVC Films for Pharmaceutical Blister PackagingPremium PVC sheet blend for pharma packaging. AVI Blis offers PVDC coating, chemical resistance & DMF registration.
- Pharma Blister PackagingAVI Blis blister film for pharma packaging — DMF-registered, free from heavy metals, ISO 9001:2015, EU and REACH...
- Packaging for Consumer Goods BrandsInnovative consumer packaging solutions designed to enhance product visibility, protection, and sustainability...
The steps
- Heat: the film runs through heating plates until soft.
- Form: air pressure or a plug pushes it into cavity moulds.
- Fill: tablets, capsules or products drop into the cavities; cameras check every pocket.
- Seal: aluminium foil with a heat-seal lacquer (medicines) or a coated card (retail) is sealed on.
- Code and cut: batch and expiry are printed or embossed, then the strip is perforated and cut to size.
What the film must do
Form evenly at speed, seal reliably to the lid, resist cracking in the cold and, for medicines, protect against moisture. AVI Blis is extruded for cold-crack resistance and shrinkage control; a PVDC coating adds barrier for moisture-sensitive drugs.
Related questions
What is cold-form (alu-alu) blistering?
Instead of heating plastic, an aluminium laminate is stretched into cavities at room temperature. It blocks light and moisture completely but is not see-through.
Why does blister film thickness matter?
Thicker film forms deeper, stiffer cavities and a better moisture barrier; thinner film saves material and suits small, flat tablets.