optimont® AF

optimont® AF – anti-fog film made from BO-PET material

optimont® AF film is suitable as an anti-fog film for food packaging. The BO-PET material from which the anti-fog film is manufactured provides good mechanical properties, high temperature resistance, and dimensional stability. In addition to packaging applications, anti-fog film is also used in many other areas, such as visor films or for partitions and roll-ups.

The transparent film is equipped on one side in such a way that moisture does not condense on the surface in the form of droplets. Instead, the moisture forms a continuous and therefore transparent moisture film. The underlying BO-PET material of optimont® AF film gives the packaging film high mechanical strength, heat resistance, dimensional stability, and good resistance to a wide range of chemicals.

optimont® AF film for food packaging

Moisture or residual moisture in food products is a challenge in packaging. This residual moisture should not condense on a packaging film or on viewing windows in cardboard packaging, even when external temperatures would normally cause this to be expected. For this reason, it is necessary to use a film with anti-fog properties for such food products.

Such a packaging film for moist products ensures that moisture formed inside the packaging does not condense as visible droplets on a viewing window film or on film packaging. A fog-free window film allows customers an unobstructed view of the packaged products. In this way, the goods appear more appealing and products are not damaged by condensed moisture dripping onto them.

For fresh products such as meat and sausage, fruit and vegetables, or cheese, packaging in a food-compliant film with anti-fog properties is therefore important for both marketing and hygiene. The use of an anti-fog film for food packaging is also important for snacks, nuts, and similar products.

Advantages of optimont® AF film

• optimont® AF film is food-compliant and therefore a perfect PET window film for fresh products
• Fogged product packaging appears unattractive and unhygienic to customers. This is avoided by optimont® AF film, ensuring appealing product presentation
• optimont® AF film provides improved moisture regulation within packaging. This enhances product shelf life, as products are not adversely affected by condensation
• optimont® AF film offers a wide range of applications. The transparent film is suitable for complete film packaging as well as for viewing windows in cardboard packaging, vacuum packaging, or as lidding film
• optimont® AF film is temperature-resistant and therefore suitable for use at low temperatures. It can be used in refrigerated display cases, during refrigerated transport, or as a film for frozen food packaging
• The opposite side of optimont® AF film is adhesion-promoted, allowing the clear film to be printed easily on this side

Disadvantages of optimont® AF film

• Strong temperature fluctuations can impair the function of the coating
• Aggressive cleaning agents can also reduce or completely eliminate the anti-fog effect of optimont® AF film
• Any anti-fog treatment involves additional costs, which must be taken into account in the overall packaging calculation
• Whether optimont® AF film is suitable for specific types of food must be clarified before production. This requires expertise and experience. Bleher support assists with the correct assessment

Areas in which optimont® AF film is used in the food sector

• optimont® AF film is used as an anti-fog cling film for fresh foods such as fish, meat, or fruit. It ensures a clear view of the product and an appealing presentation
• Environmentally friendly cardboard packaging is being used with an increasing market share in food packaging. Viewing windows made from optimont® AF film, used as film for folding cartons, allow an unobstructed view of the packaged products
• As covers for fresh food trays and other food containers, lidding films made from anti-fog film for food packaging such as optimont® AF film are used. The anti-fog treatment prevents fogging of the cover and ensures an appealing presentation, even for food packaged in this way

Further areas of application for anti-fog film

In addition to food packaging, there are other areas in which an anti-fog effect is important. These include safety goggles and face shields of all kinds, ski goggles, or viewing windows in helmets, whether for motorcycling or occupational safety. Transparent partition walls for work areas or between customers and staff are also often made from anti-fog film. The same applies to roll-ups used for temporary separation or advertising purposes.

There are also areas of application in industrial manufacturing where fogging would lead to disruptions in the production process. In these cases as well, fog-free window films are used.

Some technical data for optimont® AF film

optimont® AF film is available in thicknesses from 36 to 250 µm, corresponding to a basis weight of 50 to 349 g/m². The melting point is 252° Celsius, and the temperature resistance ranges from minus 70 to plus 150° Celsius. The light transmission of optimont® AF film is 89 percent.

Tensile strength ranges between 1800 and 2000 kg/cm² depending on thickness. Elongation at break is between 130 and 150 percent in the machine direction and between 120 and 140 percent transverse to the machine direction.

Materials for anti-fog film for food packaging and other applications

In addition to films made from BO-PET material such as optimont® AF film, anti-fog films are also manufactured from polycarbonate (PC) or acrylic. Films made from these materials achieve the anti-fog effect through a special coating that prevents fogging.

However, there are also films that provide natural anti-fog protection. These include, for example, films made from CDA (cellulose diacetate).

The anti-fog film optimont® CDA as an alternative to optimont® AF film

CDA is produced from cellulose obtained from thinning wood and features a natural anti-fog effect. The crystal-clear film made from renewable raw materials is food-compliant and certified compostable. optimont® CDA film has high surface tension and is scratch-resistant.

The transparent film is suitable as a viewing window for packaging and, outside the food sector, for window laminations, reverse laminations, and print lamination. For the application areas in which it can be used, optimont® CDA film represents an environmentally friendly alternative to optimont® AF film.

However, optimont® CDA film is not mechanically as strong as anti-fog films made from other materials, in particular films made from BO-PET. In applications where, in addition to an attractive presentation, mechanical strength of the packaging material is also required, films made from petrochemical raw materials currently still outperform optimont® CDA film made from renewable raw materials.