A laminating adhesive that is completely free of GLYMO, epoxy silane and heavy metals, making it suitable for food-safe packaging, has been developed by Henkel.
Designed for packaging applications that include thermal processes such as sterilisation, Loctite Liofol LA 2798 has been designed as a modular system. The base component can be combined with different hardeners for the respective area of application, including sterilisation and hot-filling processes.
The fields of application range from pet food and medical applications to convenience products.
“Common flexible packaging adhesives in the high-performance segment may still rely on GLYMO as an adhesion promoter,” explained Helga Garmann, manager of product development polyurethanes Europe at Henkel. “Henkel, however, has always attached the highest importance to offering clean and non-critical formulations.” Following the 11th Amendment to the EU Plastics Regulation (EU 10/2011), GLYMO has now been assessed as potentially genotoxic. A limit of 0.15μg/kg has been defined to ensure its safe use for food applications. Nevertheless, it means the packaging producer has to verify that its concentration as well as that of its derivatives remains below the specified migration limits under conditions of use.
“As testing is complex, we recommend the use of adhesives that do not contain any GLYMO,” she added.
Loctite Liofol LA 5028 and LA 5036 are suitable for contents such as dried animal food or hot filling goods. These can be used for boiling and pasteurisation, placing this system in the medium-high performance segment. For high performance, Henkel offers the aliphatic hardener Loctite Liofol LA 7371, which is suitable for 45-minute sterilisation processes at 134 deg C. It is suitable for baby foods.
For packaging and sterilising liquid, particularly aggressive filling goods such as fatty foods and oily contents like cat food, Henkel recommends a combination with Loctite Liofol LA 5802.
More information from Henkel, Henkelstrasse 207, 40599 Düsseldorf, Germany. Tel: 49 211 797 0. Web: Henkel.de