With the rapid development of industries such as food, medicine, and daily chemicals, multi-layer laminated flexible packaging has taken the dominant position in the packaging market due to its advantages of lightness, preservation, and light-blocking. In the flexible packaging lamination process, adhesives are the key raw materials that determine the firmness between packaging layers, the safety for use, and the service life. Nowadays, polyurethane laminating adhesives, with their comprehensive performance advantages, have completely replaced traditional adhesives and become the absolute mainstream material in the field of soft packaging lamination
The polyurethane laminating adhesive has extremely strong adaptability and can firmly bond various soft and hard substrates such as PET, OPP, nylon film, aluminum foil, and paper. It perfectly addresses the industry pain points of significant polarity differences on the surfaces of different film materials and difficult adhesion. The cured adhesive layer has excellent flexibility and outstanding resistance to bending and peeling. It can adapt to various mechanical external forces such as packaging cutting, bag making, and transportation compression, effectively avoiding packaging delamination and glue detachment problems. At the same time, it is resistant to high and low temperatures and medium corrosion. It can meet the low-temperature storage requirements of frozen food and can also be adapted to the high-temperature sterilization process of cooked food. It has excellent resistance to oil, acid, alkali, and spicy corrosion and is suitable for all types of food packaging usage scenarios.
Under the backdrop of increasingly strict environmental protection policies, polyurethane laminating adhesives have also completed a green upgrade. The industry has gradually shifted from solvent-based products to solvent-free and water-based polyurethane laminating adhesives, achieving near-zero emissions of VOCs and conforming to national environmental protection production standards. At the same time, the new generation of products have low odor and low migration, meeting the safety testing standards for food contact and pharmaceutical packaging, and filling the environmental shortcomings of earlier products.
Compared with traditional adhesives such as acrylic and chloroprene rubber, polyurethane laminating adhesives have a wider adaptability and a higher overall cost performance. In the future, as flexible packaging upgrades towards lightweight, high barrier, green and safe directions, high-performance polyurethane laminating adhesives will continue to deeply penetrate the composite market and lead the high-quality development of the flexible packaging bonding material industry.
