Flexible packaging applications

Innovative large-area coating for flexible packaging

Protection of the environment through the responsible use of resources is one of the major challenges facing the world both today and for the future. Aluminum foils and aluminum-plastic laminates once used as packaging materials, have been replaced by highly innovative, metalized plastic films and papers. The valuable properties of these materials are environmental sustainability, high protection due to superb barrier properties, and robustness combined with low production costs.

The coating technology in the LEYBOLD OPTICS PAK series and the LEYBOLD OPTICS SEC systems is based on thermal evaporation of different materials. The individual sources, made up of ceramics or special metal sheets, are resistance-heated consumers. Manufacturing of coated flexible plastic substrates and paper in high-volume production equipment is not only an innovation brought about by uniform, thin-layer coating technology, but also due to careful thermal management of substrates while processing. The films, with thicknesses several times thinner than human hair, are exposed to temperatures far higher than their own temperature compatibility.

Flexible packaging
Flexible plastic substrates with medium-thickness coatings make up, by far, the major proportion of the total market. These products are mainly used for flexible packaging – for instance in the food packaging industry; here, the non-transparent aluminum or transparent aluminum-oxide coating serves an important barrier function, rendering the wrapping impermeable to oxygen and water vapor. The rise in demand for thin-film packaging, in combination with the importance of barrier properties, already long predicted in earlier market trend studies, has been confirmed in recent years. It is now highly probable that the sector will see corresponding future growth, due in no small part to the emergence of a consumer middle class in among large populations around the globe.

Further applications in the flexible packaging industry, particularly in and around niche products, are thick metal coatings on plastic substrates used in packaging of highly photosensitive items such as delicate electronics, and metal coatings on paper used for e.g. beer labels and cigarette packet inserts.

Interlayers for architectural glass panels
Thin-layer coatings on flexible plastic substrates are also used to form interlayers within architectural glass panels used in buildings. They deflect sunlight to prevent excessive heat absorption, while remaining completely transparent to provide optimum light transmission for the interior. Layer uniformity is the topmost criterion for quality and is directly linked to the performance and innovative design of the evaporation source in Bühler Leybold Optic’s coating equipment.

Protection and security
There is a wide range of different applications in the security and counter-fraud industry. Within these sectors, small holograms or stickers in the form of labels for immediate and simple control, identification or authentication are extremely common. These kinds of products are made from demanding interference layers, and also from standard metal coatings on flexible plastic substrates with holographic structures.

Identity, travel documents, security, vehicle protection, fiduciary documents, banknotes, brand and products protection are just a few of the possible applications in the ongoing fight against counterfeiting and fraud.