What is Thermoform Packaging? Bottom and Top Film Guide For Automatic Filling Lines

Thermoform packaging is based on automatic thermoform-filling (FFS) machines, the bottom film is shaped by heat and the placement of the product and then close by the top film. Meat has become the sector standard in cheese, şarcuteri, ready-made food and seafood packaging.

How Does Thermoform Process Work?

1. The bottom film is heated, and it is brought into the shape of the mold with vacuum/print (deep pull).
2. The product is automatically placed on the formed chambers.
3. The upper film is welded on the bottom film. Vacuum or modified atmosphere (MAP) can be applied at this stage.
4. Package is cut and labeled.

Thermoform Bottom Movies

The bottom film is the part of the product's weight and form, so it's high deep tensile (forming) capability Home and require mechanical strength. Common structures:

• PA/PE: Good mechanical strength and medium-high gas barrier. For general purpose vacuum and thermoform applications.
• PA/EVOH/PE: Very high oxygen barrier thanks to EVOH layer. For long shelf life and MAP applications.

GKK Foil thermoform bottom films are produced in 40–250 micron range and different barrier/forming performances.

Thermoform Top Movies

The upper film is the cover of the package and is usually selected according to two basic needs:

• Peel (can be) top films: Films with PP/PE or PE-based, controlled peeling strength. The consumer’s package protects the sealing during the shelf while opening easily.
• Top films with high barrier (e.g. PET+EVOH): Completes oxygen barrier in MAP applications; increases product visibility with anti-fog (anti-rust) options.

Bottom and Top Film Compliance

Bottom and top film in thermoform packaging with each other welding compliance u should be inside. PE inner layered bottom film usually gives good welding with PE or PP/PE inner layer top film. False match leads to leakage and shelf life loss in welding lines. Therefore, sub and top films should be supplied as a one supplier, a compatible set.

Choosing the Right Thermoform Film

• Hopper depth: high forming ability bottom film for deep chambers.
• Shelf life goal: PA/EVOH/PE bottom film + high barrier top film for long shelf life.
• Consumer experience: peel top film for easy opening.
• Visibility: anti-fog and high transparency.
• Line speed: welding and forming properties suitable for the type of your machine.

Let’s plan the bottom and top movie set compatible for your thermoform line — Contact GKK Foil.