optimont® CDA

optimont® CDA film – the biological alternative to many types of film

Under the general term optimont® CDA film, Folientechnik Bleher offers various environmentally friendly films based on cellulose diacetate. The underlying CDA material is a product made from renewable raw materials, as it is manufactured from wood fiber cellulose. In addition, CDA films are compostable. They therefore meet both requirements that are placed on a bio-based film: production from renewable raw materials and compostability.

optimont® CDA films impress with their excellent ultra-clear transparency of 0.6 percent haze. For a “bio film,” this is an outstanding value. As a result, they are suitable, for example, as viewing window film in packaging.

The manufacturing process of optimont® CDA film

The basis for the production of optimont® CDA films is wood fibers. The fibers are dissolved in acetone. Through complex filtration and degassing processes as well as further preparatory steps, a polymer solution is obtained, also referred to as a spinning solution. Acetone used at the beginning of the production process can be recovered and reused in the further manufacturing process.

To produce optimont® CDA film, the spinning solution is cast onto a high-gloss polished stainless steel belt that moves continuously. In a precisely controlled drying process, the film suitable for further processing is then produced. The film can be cut and wound into rolls. Remaining pieces generated during cutting are recycled and fed directly back into the production process.

Areas of application for optimont® CDA film

optimont® CDA films can replace films made from polypropylene, PVC, or polyester in many application areas. Important fields of application include, for example:

• Viewing window reverse laminations for packaging
• Food packaging
• Thermoforming applications
• Industrial applications
• Print laminations

Recyclability of optimont® CDA film

Packaging waste is not composted on a large scale. Therefore, for packaging film it is important that a biodegradable film is also a recyclable film at the same time. For optimont® CDA film, an independent study by the Papiertechnische Stiftung (PTS) found that cardboard packaging with viewing windows made from these films can be considered suitable for the paper recycling stream. The study was conducted according to the method PTS-RH 021:2012, and the material was examined based on three parameters:

• Recyclable content, amount in percent of the material available for recycling in a paper mill
• Effects on process performance in the recycling procedure
• Cleanliness and quality of the recycled material

As a result of the tests, it was determined that cardboard packaging with a viewing window made from optimont® CDA film is suitable for recycling in standard household waste paper collection.

Properties of optimont® CDA films

• Transparent film with a good transmission rate for moisture
• Clear film with good, natural anti-fog properties
• Good transparency for UV light
• Manufactured from renewable raw materials from sustainable cultivation (PEFC)
• Home-compostable in approx. 14 weeks for material thicknesses up to 115 µm
• Biodegradable (DIN EN 13432)
• Food-compliant, transparent film
• Can be easily and safely used as a reverse-laminated viewing window film for folding cartons

Bleher products in the optimont® CDA film range

• optimont® CDA film 15 to 95 µm These films are untreated and crystal clear. They feature a natural anti-fog effect, are food-compliant, compostable, and recyclable. The above-average flatness facilitates further processing. Tensile strength is between 80 and 110 N/mm². The softening temperature is specified as 140° Celsius, and the glass transition temperature as 120° Celsius. Surface tension is between 38 and 42 mN/m.
• optimont® CDA film 115 to 500 µm The thicker optimont® CDA films have the same properties as the thinner films up to tensile strength. The softening temperature is 127° Celsius, and the glass transition temperature is 92° Celsius. Surface tension is specified as 34 to 38 mN/m.
• optimont® CDA-BIOSEAL optimont® CDA-BIOSEAL is a film with a one-sided, bio-certified and compostable heat-sealing layer. The film is crystal clear and is characterized by its sealing capability to cellulose acetate, pulp trays, PET, and PLA, as well as many other types of plastics. For further processing, it is important to note that the sealable surface is located on the inside of the roll. optimont® CDA-BIOSEAL was developed for thermal lamination on uncoated cardboard and is also suitable for heat sealing to itself as well as to the plastics mentioned above.

Sustainability of optimont® CDA Films

In times of climate change and the targeted transformation of the economy toward CO2 neutrality, sustainable films are increasingly in demand today. optimont® CDA films meet both key requirements for a sustainable film: optimont® CDA film is produced from renewable raw materials and is readily compostable. In addition, the film is also recyclable through the waste paper cycle. Manufacturers who place importance on sustainability in their production are also interested in such sustainable film products for packaging applications. Although the complex production process is energy-intensive, the savings in petroleum-based raw materials and the other sustainable product properties of the films offset this disadvantage.